Journal articles on the topic 'Astronomical sciences not elsewhere classified'

To see the other types of publications on this topic, follow the link: Astronomical sciences not elsewhere classified.

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 24 journal articles for your research on the topic 'Astronomical sciences not elsewhere classified.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.

1

WALTON, JOHN K., and DAVID TIDSWELL. "‘Classified at random by veritable illiterates’: the taking of the Spanish census of 1920 in Guipúzcoa province." Continuity and Change 20, no. 2 (August 2005): 287–313. http://dx.doi.org/10.1017/s0268416005005503.

Full text
Abstract:
This article offers an approach through administrative and cultural history to the problems associated with gathering and processing data for the Spanish national census of 1920, and by implication for earlier Spanish censuses. It focuses on the Basque province of Guipúzcoa, making use of correspondence between the central statistical office in Madrid, the provincial jefe de estadística and the localities, and of reports on three problematic towns within the province. The issues that emerge regarding ‘undercounting’, the definition of administrative boundaries and the classification of demographic characteristics are set in the wider context of census-taking practices and problems elsewhere in Spain and in other cultures.
APA, Harvard, Vancouver, ISO, and other styles
2

Arkhipova, V. P., A. V. Zasov, R. I. Noskova, and O. K. Silchenko. "Nests of Interacting Galaxies: What is It?" Symposium - International Astronomical Union 121 (1987): 579–86. http://dx.doi.org/10.1017/s0074180900155627.

Full text
Abstract:
Kinematical and photometric studies of nests of interacting galaxies are described. Velocity fields of 22 nests were obtained using the 6-meter telescope of the Special Astronomical Observatory of Sciences Academy of USSR. UBV-photometry carried out with 125-cm telescope of Sternberg Institute has shown that the majority of nests is blue and undergoes intense star formation. Nests are found to be of different types:among them there are single SB and dwarf Irr galaxies with super-giant HII -regions as well as tight pairs and multiple systems of galaxies. Multiple systems classified as nests are shown to be dynamically stable.
APA, Harvard, Vancouver, ISO, and other styles
3

Hoeppe, Götz. "Medium, calculation, play: On digital images in scientific practice." Social Studies of Science 49, no. 5 (September 5, 2019): 758–84. http://dx.doi.org/10.1177/0306312719871356.

Full text
Abstract:
Latour’s notion of immutable mobiles relates the circulability of certain objects to, among other features, their immutability, readability and combinability. As such it does not distinguish between, say, hand-drawn maps and machine-generated graphs. How, though, does the medial ‘microstructure’ of immutable mobiles matter to socially shared uses? Would, for example, digital images as bounded grids of nonoverlapping square pixels, each representing a numerical value, shape how distributed scientific work unfolds? In this article, I begin with reviewing attempts to link the microstructure of media to their communicative uses, focusing on Luhmann’s relational account of media as loosely coupled substrates in which more rigid forms can become manifest. Drawing on an ethnography of astronomical research, I then inquire into how the scientists involved reasoned about their uses of media from within their practices. They used digital photographic exposures as ‘workable objects’ whose usefulness was not guaranteed initially. Local work was oriented to potential reuses of images (as processed exposures) by researchers elsewhere, as demonstrated by concerns over the integrity of images, the possibility of describing their work with reasonable efforts, as well as by negotiating acceptable elements in calculations so as to reveal stabilized phenomena. In doing so, scientists insisted on the need to play or experiment, suspending sequential work for explorations oriented toward deciding which action among alternatives to make consequential. This was part of a more extended ‘calculative game’ that points, through its orientation to reasonable agreement and delimitations of legitimate efforts, to the social order of this work. The medium, here conceived as images deemed accountable to reuses elsewhere, is a social achievement. Recognizing this may help to better understand the reusability of scientific data and its challenges.
APA, Harvard, Vancouver, ISO, and other styles
4

Rivera, Paola A., Akash Gupta, and Ninani Kombo. "Treatment of non-infectious retinal vasculitis." Therapeutic Advances in Ophthalmology 15 (January 2023): 251584142311527. http://dx.doi.org/10.1177/25158414231152761.

Full text
Abstract:
Retinal vasculitis (RV) refers to an entity in which the retinal vasculature is inflamed, frequently with indications of inflammation elsewhere in the eye. Non-infectious RV can be idiopathic or associated with systemic disease, ocular conditions, and malignancy. It can also be classified based on the vessel affected: artery, vein, or both. Due to the lack of strong evidence-based treatment trials and algorithms for RV, physicians must often rely on their experience, which creates great variability in treating this entity. This article provides an overview of various treatment modalities used in the management of non-infectious RV, with a focus on immunomodulatory therapies. We outline a potential stepwise approach of starting with steroids to control the acute inflammation and subsequently changing to immunomodulatory therapy (IMT) for long-term treatment.
APA, Harvard, Vancouver, ISO, and other styles
5

Masaki, Motofumi, and Akira Koizumi. "Demographic characteristics and their genetic implications in a small island." Journal of Biosocial Science 20, no. 2 (April 1988): 225–34. http://dx.doi.org/10.1017/s0021932000017454.

Full text
Abstract:
SummaryThe family registration records from a village population in a small island of Japan are used to assess the effect of demographic differentiation within a population on genetic measures. When the couples studied are classified by birth cohorts and origins, wives of the couples where one spouse came from elsewhere were older at marriage and had a shorter duration of marriage or registration than wives where both spouses were natives of the village. The mean number of offspring is statistically smaller in the former except for the latest cohort, due mainly to out-migration during the reproductive ages which also resulted in low rates of marriage among the offspring within the village. This leads to a small effective population size and an increased likelihood of genetic drift in the overall population.
APA, Harvard, Vancouver, ISO, and other styles
6

Rhee, Seongha, and Hyun Jung Koo. "Multifaceted gustation." Food and terminology 23, no. 1 (November 10, 2017): 38–65. http://dx.doi.org/10.1075/term.23.1.02rhe.

Full text
Abstract:
Korean has a large number of taste terms and the paradigm is continuously expanding since the lexicalization operates systematically on a few robust principles. Based on the taste terms collected from lexicons, dictionaries, web-postings, and elsewhere, we classified the terms and analyzed the lexicalization patterns. In addition to the widely-known five classes of tastes, i.e., sweet, salty, sour, bitter and umami, Korean has three more classes in the basic category, i.e., pungent, fishy and bland. A large number of tactile sensory words to describe the touch sensations in the mouth at the tasting event and expressions denoting characteristic food texture and mastication also join in creating a rich taste vocabulary. The Korean taste lexicalization system is equipped with the means to signal diverse aspects of gustatory sensation, i.e., intensity, depth, purity and duration. Among such means are vowel polarity, consonantal sound symbolism, reduplication and onomatopoeia. The systematicity of taste lexicalization contributes to the plasticity of the paradigm, making the Korean taste vocabulary one of the most productive and elaborate paradigms.
APA, Harvard, Vancouver, ISO, and other styles
7

Ku, Teh-Lung, M. Ivanovich, and Shangde Luo. "U-Series Dating of Last Interglacial High Sea Stands: Barbados Revisited." Quaternary Research 33, no. 2 (March 1990): 129–47. http://dx.doi.org/10.1016/0033-5894(90)90014-c.

Full text
Abstract:
AbstractU-series chronologies of the emerged coral limestone terraces on Barbados, West Indies, together with those of the terraces from New Guinea, have formed the basis for most late Pleistocene eustatic models. The so-called “Barbados sea level model” has been challenged in recent years, however. A major issue is whether during oxygen isotope stage 5e, when Rendezvous Hill reef complex on Barbados Island formed, the sea rose above the present position for one relatively brief period of <10,000 yr, or for two or more periods spanning approximately from 140,000 to 115,000 yr B.P. Evidence for the latter scenario has not come from initial studies of Barbados but from elsewhere; it is also inconclusive because of the dating uncertainties involved. We have carried out careful redeterminations of U-series ages on a suite of 29 Acropora palmata samples systematically collected from four of the lowest terraces on the island. Diagenetic disturbance may have caused the age spreads at some sampling outcrops. A model for the diagenetic exchange of uranium isotopes in coral samples with those in groundwater explains the anomalous 234U/238U ratios in samples with apparently unaltered mineralogy (aragonite) and trace element (Mg and Sr) chemistry. It shows that age dispersions of 5–10% can be engendered by a U exchange coefficient of the order of 10−6 yr−1. The lower-limit terrace ages, estimated from averaging the multiple measurements, are 81,000 ± 2000 yr (Worthing), 105,000 ± 1000 yr (Ventnor), 120,000 ± 2000 yr (Maxwell), and 117,000 ± 3000 yr (Rendezvous Hill). No evidence was found of previously inferred bipartite sea levels centering around 118,000 and 135,000 yr ago. This study documents the need of dating coral with the high precision/sensitivity mass-spectrometric techniques for future resolution of the temporal relationships among sea level changes, climate oscillations, and astronomical forcing—relationships originally addressed by the Barbados sea level model.
APA, Harvard, Vancouver, ISO, and other styles
8

Conesa, Francesc C., Hector A. Orengo, Agustín Lobo, and Cameron A. Petrie. "An Algorithm to Detect Endangered Cultural Heritage by Agricultural Expansion in Drylands at a Global Scale." Remote Sensing 15, no. 1 (December 22, 2022): 53. http://dx.doi.org/10.3390/rs15010053.

Full text
Abstract:
This article presents AgriExp, a remote-based workflow for the rapid mapping and monitoring of archaeological and cultural heritage locations endangered by new agricultural expansion and encroachment. Our approach is powered by the cloud-computing data cataloguing and processing capabilities of Google Earth Engine and it uses all the available scenes from the Sentinel-2 image collection to map index-based multi-aggregate yearly vegetation changes. A user-defined index threshold maps the first per-pixel occurrence of an abrupt vegetation change and returns an updated and classified multi-temporal image aggregate in almost-real-time. The algorithm requires an input vector table such as data gazetteers or heritage inventories, and it performs buffer zonal statistics for each site to return a series of spatial indicators of potential site disturbance. It also returns time series charts for the evaluation and validation of the local to regional vegetation trends and the seasonal phenology. Additionally, we used multi-temporal MODIS, Sentinel-2 and high-resolution Planet imagery for further photo-interpretation of critically endangered sites. AgriExp was first tested in the arid region of the Cholistan Desert in eastern Pakistan. Here, hundreds of archaeological mound surfaces are threatened by the accelerated transformation of barren lands into new irrigated agricultural lands. We have provided the algorithm code with the article to ensure that AgriExp can be exported and implemented with little computational cost by academics and heritage practitioners alike to monitor critically endangered archaeological and cultural landscapes elsewhere.
APA, Harvard, Vancouver, ISO, and other styles
9

Ridgway, Jessica P., Jessica Schmitt, Ellen Almirol, Monique Millington, Erika Harding, and David Pitrak. "Electronic data sharing between public health department and clinical providers improves accuracy of HIV retention data." Open Forum Infectious Diseases 4, suppl_1 (2017): S421—S422. http://dx.doi.org/10.1093/ofid/ofx163.1059.

Full text
Abstract:
Abstract Background Retention in care is critical for treatment and prevention of HIV. Many HIV care clinics measure retention rate, but data are often incomplete for patients who are classified as lost to follow-up but may be actually in care elsewhere, moved, or died. The Data to Care (D2C) initiative supports data sharing between health departments and HIV providers to confirm patient care status and facilitate reengagement efforts for out of care HIV patients. Methods The University of Chicago Medicine (UCM) provided an electronic list to the Chicago Department of Public Health (CDPH) of adult HIV-positive patients whose retention status was not certain. Retention in care was defined as at least 2 visits &gt;90 days apart within the prior 12 months. CDPH matched this list of patients with data from the Chicago electronic HIV surveillance database. Matches were based on patient name, including alternative spellings and phonetics, and birth date. CDPH also cross-checked patient names with the CDC’s national enhanced HIV-AIDS Reporting System (eHARS) database. CDPH provided UCM with patient current care status, i.e., patient was in care elsewhere (as verified by lab data), moved out of state, or deceased. Results 780 HIV-positive patients received care in the UCM adult HIV clinic from January 1, 2013 to March 31, 2017. Of these, 360 were retained in care as of March 2017. We shared data with CDPH for 492 patients. Of these, 294 (59.8%) were matched, and 168 (34.1%) had a date of last medical care provided. See Table 1 for patient dispositions, before and after data sharing. 24 (13.4%) of patients believed to be lost to follow up according to UCM records were confirmed either transferred care or deceased according to health department data. Conclusion Data sharing between the health department and HIV providers can improve data accuracy regarding retention in care among people living with HIV. Disclosures J. P. Ridgway, Gilead FOCUS: Grant Investigator, Grant recipient; D. Pitrak, Gilead Sciences FOCUS: Grant Investigator, Grant recipient
APA, Harvard, Vancouver, ISO, and other styles
10

Bannister, Frank, and Dan Remenyi. "Acts of Faith: Instinct, Value and it Investment Decisions." Journal of Information Technology 15, no. 3 (September 2000): 231–41. http://dx.doi.org/10.1177/026839620001500305.

Full text
Abstract:
Although well over 1000 journal articles, conference papers, books, technical notes and theses have been written on the subject of information technology (IT) evaluation, only a relatively small subset of this literature has been concerned with the core issues of what precisely is meant by the term ‘value’ and with the process of making (specifically) IT investment decisions. All too often, the problem and highly complex issue of value is either simplified, ignored or assumed away. Instead the focus of much of the research to date has been on evaluation methodologies and, within this literature, there are different strands of thought which can be classified as partisan, composite and meta approaches to evaluation. Research shows that a small number of partisan techniques are used by most decision makers with a minority using a single technique and a majority using a mixture of such techniques of whom a substantial minority use a formal composite approach. It is argued that, in mapping the set of evaluation methodologies on to what is termed the investment opportunity space, that there is a limit to what can be achieved by formal rational evaluation methods. This limit becomes evident when decision makers fall back on ‘gut feel’ and other non-formal/rigorous ways of making decisions. It is suggested that an understanding of these more complex processes and decision making, in IT as elsewhere, needs tools drawn from philosophy and psychology.
APA, Harvard, Vancouver, ISO, and other styles
11

Oviatt, Charles G., David B. Madsen, and Dave N. Schmitt. "Late Pleistocene and early Holocene rivers and wetlands in the Bonneville basin of western North America." Quaternary Research 60, no. 2 (September 2003): 200–210. http://dx.doi.org/10.1016/s0033-5894(03)00084-x.

Full text
Abstract:
AbstractField investigations at Dugway Proving Ground in western Utah have produced new data on the chronology and human occupation of late Pleistocene and early Holocene lakes, rivers, and wetlands in the Lake Bonneville basin. We have classified paleo-river channels of these ages as “gravel channels” and “sand channels.” Gravel channels are straight to curved, digitate, and have abrupt bulbous ends. They are composed of fine gravel and coarse sand, and are topographically inverted (i.e., they stand higher than the surrounding mudflats). Sand channels are younger and sand filled, with well-developed meander-scroll morphology that is truncated by deflated mudflat surfaces. Gravel channels were formed by a river that originated as overflow from the Sevier basin along the Old River Bed during the late regressive phases of Lake Bonneville (after 12,500 and prior to 11,000 14C yr B.P.). Dated samples from sand channels and associated fluvial overbank and wetland deposits range in age from 11,000 to 8800 14C yr B.P., and are probably related to continued Sevier-basin overflow and to groundwater discharge. Paleoarchaic foragers occupied numerous sites on gravel-channel landforms and adjacent to sand channels in the extensive early Holocene wetland habitats. Reworking of tools and limited toolstone diversity is consistent with theoretical models suggesting Paleoarchaic foragers in the Old River Bed delta were less mobile than elsewhere in the Great Basin.
APA, Harvard, Vancouver, ISO, and other styles
12

Venyo, Anthony Kodzo-Grey. "Signet Ring Cell Carcinoma of the Prostate Gland: A Review and Update." Cancer Research and Cellular Therapeutics 5, no. 3 (July 26, 2021): 01–14. http://dx.doi.org/10.31579/2640-1053/082.

Full text
Abstract:
Signet-ring cell carcinoma of the prostate gland (SRCCP) an uncommon and aggressive malignant tumour of the prostate gland which is characterized by histopathology examination features of compression of the nucleus into the form of a crescent by a large cytoplasmic vacuole. SRCCPs that have so far been reported have been either (a) primary tumours, metastatic tumours with the primary tumour elsewhere with the gastro-intestinal tract being the site of the primary tumour but the primary tumour could originate elsewhere, and additionally some reported SRCCPs have been classified as carcinoma of unknown primary. SRCCP could be a pure tumour or a tumour that is contemporaneously associated with other types of tumour including various variants of adenocarcinoma. SRCCP can manifest in various ways including: Incidental finding following prostatectomy that has been undertaken for a presumed benign prostatic hyperplasia, lower urinary tract symptoms, visible and non-visible haematuria, raised levels of serum PSA but some SRCCPs have been diagnosed with normal / low levels of serum PSA, there may be a history of dyspepsia in cases of metastatic signet-ring cell carcinoma in association with contemporaneous primary signet-ring cell carcinoma of the stomach or there may be a past history of surgical treatment for signet-ring cell carcinoma of the gastrointestinal tract, or bleeding from the gastrointestinal tract in cases of upper gastrointestinal tract and rectal bleeding as well as change in bowel habit for primary tumours of the anorectal region, retention of urine, and rarely a rectal mass in the case of SRCCP with an anorectal primary tumour. In order to exclude a primary signet ring cell carcinoma elsewhere, a detailed past medical history is required as well as radiology imaging including contrast – enhanced computed tomography (CECT) scan and contrast-enhanced magnetic resonance imaging (CEMRI) scan as well as upper gastrointestinal endoscopy and colonoscopy to exclude a primary lesion within the gastrointestinal tract. Diagnosis of SRCCP requires utilization of the histopathology and immunohistochemistry examination features of prostate biopsy, prostatic chips obtained from trans-urethral resection of prostate specimen or radical prostatectomy specimen. SRCCPs upon immunohistochemistry staining studies tend to show tumour that tend to exhibit positive staining for the following tumour markers as follows: PSA – positive staining for PSA has been variable in some studies, AE1/AE3, CAM 5.2, Ki-67 with a mean of 8%, PAS-diastase, Mucicarmine (50%), Alcian blue (60%), Alpha-methyl-acyl coenzyme A racemase (P504S), and Cytokeratin 5/6. SRCCPs also tend to exhibit negative staining for: Bcl2 (rare positive), and CEA (80%). Traditionally the treatment of Primary Signet-Ring Cell Carcinoma of the Prostate Gland has tended to be similar to the treatment of the traditional adenocarcinoma of the prostate gland which does include: hormonal treatment, radiotherapy, and surgery. Nevertheless, considering that primary SRCCPs and metastatic SRCCPs that have been reported in the literature have generally tended to be associated with an aggressive biological behaviour, even though there is no consensus opinion on the treatment of the disease it would be strongly recommended that these tumours that tend to be associated with rapid progress of the disease and poor survival there is an urgent need to treat all these tumours with aggressive surgery including radical prostatectomy plus adjuvant therapies including: radical radiotherapy, combination chemotherapy, selective prostatic angiography and super-selective embolization of the artery feeding the tumour including intra-arterial infusion of chemotherapy agents directly to the tumour, radiofrequency ablation of the tumour as well as irreversible electroporation of the tumour which should form part of a global multicentre study of various treatment options. With regard to metastatic signet-ring cell carcinomas of the prostate gland with a contemporaneous primary tumour elsewhere the primary tumour should also be treated by radical and complete excision of the primary tumour plus radical surgery and aggressive adjuvant therapy. Considering that SRCCPs have tendered not to respond well to available chemotherapy agents, there is need for urologists, oncologists, and pharmacotherapy research workers to identify new chemotherapy medicaments that would more effectively and safely destroy signet-ring cell tumours in order to improve upon the prognosis.
APA, Harvard, Vancouver, ISO, and other styles
13

Hasan, Alaa B. "A Computer Simulation of Hubble Telescope Including Eyepiece Nano- Sensors to Increase Optical Efficiency." Pakistan Journal of Medical and Health Sciences 16, no. 12 (December 31, 2022): 755–58. http://dx.doi.org/10.53350/pjmhs20221612755.

Full text
Abstract:
The Hubble telescope is characterized by the accuracy of the image formed in it, as a result of the fact that the surrounding environment is free of optical pollutants. Such as atmospheric gases and dust, in addition to light pollution emanating from industrial and natural light sources on the earth's surface. The Hubble telescope has a relatively large objective lens that provides appropriate light to enter the telescope to get a good image. Because of the nature of astronomical observation, which requires sufficient light intensity emanating from celestial objects (galaxies, stars, planets, etc.). The Hubble telescope is classified as type of the Cassegrain reflecting telescopes, which gives it the advantage of eliminating chromatic aberration. Zemax optical design program was used to simulate the design of the Hubble telescope with nanosensors eyepiece, and to evaluate its performance through a set of analysis tools in the program, by changing some of the optical parameters that affect the performance of the telescope. The results proved needing of the imaging optical system (telescope) to align the observed object to avoid off-axial aberration. When the angle of incidence of the rays is changed to an appropriate extent, the image is negatively affected as a result of the increase in the amounts of aberration in it. The simulation also showed the similarity of the optical parameters that are related to the engineering design to get the best picture, through the analysis tools used in the program. Keywords: Reflective telescope, Nano sensors, Hubble, optical efficiency, Zemax program.
APA, Harvard, Vancouver, ISO, and other styles
14

Xu, Feng, Zhaofu Li, Shuyu Zhang, Naitao Huang, Zongyao Quan, Wenmin Zhang, Xiaojun Liu, Xiaosan Jiang, Jianjun Pan, and Alexander V. Prishchepov. "Mapping Winter Wheat with Combinations of Temporally Aggregated Sentinel-2 and Landsat-8 Data in Shandong Province, China." Remote Sensing 12, no. 12 (June 26, 2020): 2065. http://dx.doi.org/10.3390/rs12122065.

Full text
Abstract:
Winter wheat is one of the major cereal crops in China. The spatial distribution of winter wheat planting areas is closely related to food security; however, mapping winter wheat with time-series finer spatial resolution satellite images across large areas is challenging. This paper explores the potential of combining temporally aggregated Landsat-8 OLI and Sentinel-2 MSI data available via the Google Earth Engine (GEE) platform for mapping winter wheat in Shandong Province, China. First, six phenological median composites of Landsat-8 OLI and Sentinel-2 MSI reflectance measures were generated by a temporal aggregation technique according to the winter wheat phenological calendar, which covered seedling, tillering, over-wintering, reviving, jointing-heading and maturing phases, respectively. Then, Random Forest (RF) classifier was used to classify multi-temporal composites but also mono-temporal winter wheat development phases and mono-sensor data. The results showed that winter wheat could be classified with an overall accuracy of 93.4% and F1 measure (the harmonic mean of producer’s and user’s accuracy) of 0.97 with temporally aggregated Landsat-8 and Sentinel-2 data were combined. As our results also revealed, it was always good to classify multi-temporal images compared to mono-temporal imagery (the overall accuracy dropped from 93.4% to as low as 76.4%). It was also good to classify Landsat-8 OLI and Sentinel-2 MSI imagery combined instead of classifying them individually. The analysis showed among the mono-temporal winter wheat development phases that the maturing phase’s and reviving phase’s data were more important than the data for other mono-temporal winter wheat development phases. In sum, this study confirmed the importance of using temporally aggregated Landsat-8 OLI and Sentinel-2 MSI data combined and identified key winter wheat development phases for accurate winter wheat classification. These results can be useful to benefit on freely available optical satellite data (Landsat-8 OLI and Sentinel-2 MSI) and prioritize key winter wheat development phases for accurate mapping winter wheat planting areas across China and elsewhere.
APA, Harvard, Vancouver, ISO, and other styles
15

Das, Karumampoyil Sakthidas Anoop, Dhanya Radhamany, and Freerk Molleman. "Community Structure in an Isolated Tropical Forest Biome: One Year of Fruit-Feeding Butterfly Trapping in Four Habitats in the Western Ghats, India." Diversity 15, no. 1 (December 28, 2022): 36. http://dx.doi.org/10.3390/d15010036.

Full text
Abstract:
Insect communities in tropical forests tend to be structured vertically and with respect to tree fall gaps and edges. Furthermore, insect communities vary over time. Insight into such habitat specificity and temporal variation is needed to design and interpret biodiversity surveys and to compare conservation value among habitats. Some aspects of tropical insect community structure, such as the proportion of canopy specialists and temporal variation, vary among biogeographical regions and climatic zones. To date, few regions have been sampled systematically, so generalization remains difficult. We compared fruit-feeding butterfly communities among understory, canopy, natural treefalls, and forest edge, in a tropical forest of the Western Ghats, a strip of rainforest that is isolated from Sundaland, the large rainforest block of South-East Asia. During a yearlong study, we captured 3018 individuals belonging to 32 species and representing 14 genera. While some butterflies were captured in the canopy, no species was significantly more abundant in the canopy than in the understory. This observation was contrary to studies elsewhere in the tropics where 14–55% of the species could be classified as canopy specialists. Even though the largest number of species was captured at forest edges, species diversity was highest in the gaps. The communities at the forest edge differed importantly from those in treefall gaps: at the forest edge, we caught grassland species in addition to the forest species. Larger treefall gaps had higher butterfly abundance than smaller gaps. Both abundance and diversity peaked during the late monsoon season, and all common species in our sample also peaked during this period. The spatiotemporal community structure appears to depend on biogeography (less vertical stratification further from large forest blocks) and climate (more synchrony among species in seasonal abundance when there is a more severe dry season).
APA, Harvard, Vancouver, ISO, and other styles
16

Brice, Kylie L., Pankaj Trivedi, Thomas C. Jeffries, Michaela D. J. Blyton, Christopher Mitchell, Brajesh K. Singh, and Ben D. Moore. "The Koala (Phascolarctos cinereus) faecal microbiome differs with diet in a wild population." PeerJ 7 (April 1, 2019): e6534. http://dx.doi.org/10.7717/peerj.6534.

Full text
Abstract:
BackgroundThe diet of the koala (Phascolarctos cinereus) is comprised almost exclusively of foliage from the genusEucalyptus(family Myrtaceae).Eucalyptusproduces a wide variety of potentially toxic plant secondary metabolites which have evolved as chemical defences against herbivory. The koala is classified as an obligate dietary specialist, and although dietary specialisation is rare in mammalian herbivores, it has been found elsewhere to promote a highly-conserved but low-diversity gut microbiome. The gut microbes of dietary specialists have been found sometimes to enhance tolerance of dietary PSMs, facilitating competition-free access to food. Although the koala and its gut microbes have evolved together to utilise a low nutrient, potentially toxic diet, their gut microbiome has not previously been assessed in conjunction with diet quality. Thus, linking the two may provide new insights in to the ability of the koala to extract nutrients and detoxify their potentially toxic diet.MethodThe 16S rRNA gene was used to characterise the composition and diversity of faecal bacterial communities from a wild koala population (n = 32) comprising individuals that predominately eat either one of two different food species, one the strongly preferred and relatively nutritious speciesEucalyptus viminalis, the other comprising the less preferred and less digestible speciesEucalyptus obliqua.ResultsAlpha diversity indices indicated consistently and significantly lower diversity and richness in koalas eatingE. viminalis. Assessment of beta diversity using both weighted and unweighted UniFrac matrices indicated that diet was a strong driver of both microbial community structure, and of microbial presence/absence across the combined koala population and when assessed independently. Further, principal coordinates analysis based on both the weighted and unweighted UniFrac matrices for the combined and separated populations, also revealed a separation linked to diet. During our analysis of the OTU tables we also detected a strong association between microbial community composition and host diet. We found that the phyla Bacteroidetes and Firmicutes were co-dominant in all faecal microbiomes, with Cyanobacteria also co-dominant in some individuals; however, theE. viminalisdiet produced communities dominated by the generaParabacteroidesand/orBacteroides, whereas theE. obliqua-associated diets were dominated by unidentified genera from the family Ruminococcaceae.DiscussionWe show that diet differences, even those caused by differential consumption of the foliage of two species from the same plant genus, can profoundly affect the gut microbiome of a specialist folivorous mammal, even amongst individuals in the same population. We identify key microbiota associated with each diet type and predict functions within the microbial community based on 80 previously identifiedParabacteroidesand Ruminococcaceae genomes.
APA, Harvard, Vancouver, ISO, and other styles
17

Atrash, Shebli, Qing Zhang, Xenofon Papanikolaou, Christoph Heuck, Aziz Bakhous, Jameel Muzaffar, Al-Ola Abdallah, and Bart Barlogie. "Characteristics and Prognosis Of IgM Multiple Myeloma." Blood 122, no. 21 (November 15, 2013): 1881. http://dx.doi.org/10.1182/blood.v122.21.1881.1881.

Full text
Abstract:
Abstract Introduction Multiple Myeloma (MM) is considered a malignancy of post germinal center long-lived plasma cells. Nevertheless T-cell independent antigen stimulation before the exposure of the B-cell to the germinal center can happen and results to IgM secreting short lived plasma cells and lymphoplasmacytes representing thus a potential alternative normal counterpart for IgM plasma cell dyscrasias. IgM myeloma is an infrequent subtytpe of MM with an estimated prevalence of 0.5%. Due to its rarity little is known about its characteristics and prognosis in comparison with Waldestrom’s macroglobulinemia (WM) and the other MM subtypes. Purpose To identify the characteristics and the prognosis of IgM MM, and compare it predominantly with WM and subsequently with the rest of the MM subtypes. Methods We interogatted our Multiple Myeloma Data Base for cases of IgM MM and their respective Overall Survival (OS), Progression Free Survival (PFS), bone disease as defined by x-Rays, PET-CT and MRI, Gene Expression Profile (GEP), and common disease characteristics (anemia,calcium, creatinine) and compare it to the prognosis of WM and non-IgM MM. Diagnosis was based on the morphological and immunophenotypical findings of pathologically examined biopsy specimens along with the presence or not of typical clinical characteristics of MM (lytic bone lesions, hypercalcemia, renal failure) or typical clinical characteristics of WM (organomegaly, lymphadenopathy). Results There were 22 confirmed IgM MM cases. 14 of them presented at MIRT at initial diagnosis while 8 had previously been treated elsewhere. Osteolytic bone lesions and/or pathological fractures by x-ray and CT examination were evident in 16 cases. For the remaining 6 cases active bone focal lesions by either MRI or PET were identified in three. There was no organomegaly evident in cases with an available PET/CT at baseline, while only one had evidence of hilar and mediastinal lymphadenopathy along with calcified lung nodules. Elevated creatinine levels (>2.0 mg/dl) were evident in 4 cases at initial diagnosis. Their disease characteristics are depicted in the table 1. Median OS for IgM MM was 4.9 years while PFS could not be accurately estimated due to lack of data on patients treated elsewhere. Median OS for a historical control of 158 WM cases in MIRT was 9.2 years (Clin Lymphoma Myeloma Leuk. 11(1):139-42). Median OS of the WM group remained largely unaffected, even when the subgroup of the WM cases requiring treatment was analyzed (9.0 years).To further clarify if the IgM MM differs in terms of OS from the other isotypes of MM, we compared the IgM group to a group of 61 non-IgM MM cases which were matched by important prognostic clinical factors (age, creatinine> 2mg/dl, LDH>190u/L, b-2M >5.5mg/dl and Albumin<3.5gr/dl). No statistical difference was found for OS (p=0.846). Out of 22 cases, 14 of them had available GEP data on initial diagnosis. In 6 of these cases the cyclin D1 gene expression was high enough to be consistent with a t(11;14) translocation at FISH analysis, one case was consistent with a t(14;16) translocation, one with a t(4;14) translocation and two more were classified as belonging to the hyperdiploid subgroup. A comparative genomic analysis was performed on the IgM MM, the non-IgM MM and WM cases with available GEP data at initial diagnosis (14, 61 and 42 cases respectively). 1155 probesets that had expression level significantly different between WM and non IgM MM (FDR<3E-06) were identified. Then, the expression values of these 1155 probesets in all GEP samples, including WM, non IgM MM, and IgM MM, were used to build a clustering tree. We found that IgM MM mainly clustered with non IgM MM, supporting the findings of the clinical data. Conclusion IgM MM is a discrete clinical entity that should be distinguished from WM. Bone disease is evident in the majority of the cases, especially when specialized radiological techniques are incorporated at the initial work up. It holds a distinct prognosis from WM, while when balanced for prognostic factors that hold importance in MM it does not differ from the other MM isotypes. Finally analysis of the genetic data further supports the resemblance between IgM MM and the non IgM MM, and the difference with WM. Disclosures: Zhang: University of Arkansas for Medical Sciences: Co-inventor of the DNA probes for FISH of IGHC/IGHV (14q32), MMSET/FGFR3 (4p16), CCND3 (6p21), CCND1 (11q13), MAF (16q23), and MAFB (20q12) loci, sub. to the US Patent & Trademark Office as Prov. App# 61/726,327: Methods of Detecting 14q32 Translocations, Co-inventor of the DNA probes for FISH of IGHC/IGHV (14q32), MMSET/FGFR3 (4p16), CCND3 (6p21), CCND1 (11q13), MAF (16q23), and MAFB (20q12) loci, sub. to the US Patent & Trademark Office as Prov. App# 61/726,327: Methods of Detecting 14q32 Translocations Patents & Royalties.
APA, Harvard, Vancouver, ISO, and other styles
18

Giostra, Alessandro. "Stanley Jaki: Science and Faith in a Realist Perspective." Perspectives on Science and Christian Faith 74, no. 1 (March 2022): 59–61. http://dx.doi.org/10.56315/pscf3-22giostra.

Full text
Abstract:
STANLEY JAKI: Science and Faith in a Realist Perspective by Alessandro Giostra. Rome, Italy: IF Press, 2019. 144 pages. Paperback; $24.24. ISBN: 9788867881857. *The subject of this short introduction--Father Stanley L. Jaki (1924–2009), a giant in the world of science and religion--is more important than this book's contents, a collection of conference papers and articles published between 2015 and 2019. *Readers of this journal should recognize Jaki, a Benedictine priest with doctorates in theology and physics, 1975–1976 Gifford lecturer, 1987 Templeton Prize winner, and professor at Seton Hall University, for his prolific, valuable work in the history of the relations between theology and science. He sharply contrasted Christian and non-Christian/scientific cosmologies and unfortunately, often slipped into polemics and apologetics. The title of Stacy Trasanco's 2014 examination of his work, Science Was Born of Christianity, captures Jaki's key thesis. Science in non-Christian cultures was, in Jaki's (in)famous and frequent characterizations, "stillborn" and a "failure" (e.g., see Giostra, pp. 99, 113). Incidentally, Giostra seems unaware that various Protestant scholars shared Jaki's key thesis and arguments. *The Introduction begins with a quotation from Jaki that so-called conflicts between science and religion "must be seen against objective reality, which alone has the power to unmask illusions." Jaki continued, "There may be clashes between science and religion, or rather between some religionists and some scientists, but no irresolvable fundamental conflict" (p. 15). *This raises two other crucial aspects of Jaki's approach: his realist epistemology and his claim that, properly understood, science and Christian theology cannot be in conflict. Why? Because what Jaki opposed was not science itself--which he saw as specific knowledge of the physical world that was quantifiable and mathematically expressible--but ideologies that were attached to science in the eighteenth and nineteenth centuries, that is, materialism, naturalism, reductionism, positivism, pantheism, and atheism. *For Jaki, the real problem for Christian approaches to the natural world was the scientism which dismissed theology, especially Catholicism, as superstition, dogmatism, and delusion. Jaki followed the groundbreaking work of Pierre Duhem in arguing that the impetus theory of the fourteenth-century philosopher John Buridan was the first sign of the principle of inertia, the first law of Newtonian physics. One of the foundational shifts in the birth of a new "revolutionary" science in the Christian West was a post-Aristotelian understanding of bodies in motion (both uniform and uniformly accelerating: see chapter three for more details). *The first chapter is a bio- and bibliographical essay by an admiring Antonio Colombo that traces and situates Jaki the historian as a man of both science and faith. Chapter two lays out Jaki's critical realism and theses about the history of science and theology, in contrast to scientisms past and present that claim scientific reason as the sole trustworthy route to legitimate knowledge. The roles played by the doctrine of creation ex nihilo and the Christology of the pre-existent Logos in Jaki's cosmological thinking are also outlined. *Many readers will be most interested in the third chapter which surveys Jaki's writing about the notorious case of Galileo, condemned by the church in 1633 for defending Copernicus. Jaki detected scientific and theological errors in the positions of both Galileo and the church. For instance, Galileo did not provide proof of the motion of the earth around the sun. Nor did the church understand errors in Aristotelian science. Galileo was right, however, in arguing that the Bible's purpose was not to convey scientific knowledge; while the church's rejection of heliocentric cosmology was correct, given the dearth of convincing evidence for it. *Chapter four is of wider interest than its title, "The Errors of Hegelian Idealism," might suggest. Jaki's belief that only Christian theology could give birth to the exact sciences is reviewed, along with his rejection of conflict and concord models of faith and science. His critiques of Hegelian and Marxist views of the world are thoughtfully discussed. *Jaki was unrelentingly hostile to all types of pantheism, and Plato was the most influential purveyor of that erroneous philosophy. Chapter five outlines Jaki's objections to Platonism, as well as to Plotinus's view of the universe as an emanation from an utterly transcendent One, and to Giordano Bruno's neo-Platonic animism and Hermeticism. *Jaki's interpretation of medieval Islamic cosmologists is the subject of the fifth chapter, in which the Qur'an, Averroes, and Avicenna are examined and found wanting. Monotheism by itself could not lead to science. Incorrect theology blinded those without an understanding of the world as God's creation or of Christ as Word and Savior from seeing scientific truth. This chapter is curious in several respects. On page 98, Giostra equates Christ as the only begotten Son with Jesus as the only "emanation from the Father." Emanationism is a Gnostic, Manichaean, and neo-Platonic concept; it is not, to my knowledge, part of orthodox Catholic Trinitarian discourse. On pages 101–2, the presence of astrology in the Qur'an disqualifies it as an ancestor of modern science. But astrology then was not yet divorced from astronomy. Astrological/astronomical imagery and terminology were integral to ancient cosmologies and apocalypses, including Jewish, Christian, and Muslim ones. Lastly, pages 104–5 feature quotations in untranslated Latin. *Chapter seven is a review of the 2016 edition of Jaki's Science and Creation; this is one more example of content repeated elsewhere in the book. "Benedict XVI and the limits of scientific learning" is the eighth and final chapter. The former pope is presented as a Jaki-like thinker in his views of science and faith. Strangely, Benedict does not cite Jaki; this absense weakens Giostra's case somewhat. *Jaki--whose faith was shaped by the eminent French theologian and historian of medieval thought, Etienne Gilson--was a diehard Roman Catholic, wary of Protestant thought, defender of priestly celibacy and of the ineligibility of women for ordination. On the other hand, his study of both Duhem and Gilson probably sensitized Jaki to ideological claims made by scientists. *As a historian of science, Jaki was meticulous and comprehensive in his research with primary documents. His interpretations of historical texts were as confident and swaggering as his critiques of scientists and scientism were withering. Among Jaki's more interesting and helpful contributions to scholarship are his translations and annotations of such important primary texts as Johann Heinrich Lambert's Cosmological Letters (1976), Immanuel Kant's Universal Natural History and Theory of the Heavens (1981), and Bruno's The Ash Wednesday Supper (1984). *Personally, I have found much of value in Jaki's The Relevance of Physics (1966); Brain, Mind and Computers (1969); The Paradox of Olbers' Paradox (1969); The Milky Way (1972); Planets and Planetarians (1978); The Road of Science and the Ways to God (1978); Cosmos and Creator (1980); Genesis 1 through the Ages (1998); The Savior of Science (2000); Giordano Bruno: A Martyr of Science? (2000); Galileo Lessons (2001); Questions on Science and Religion (2004); The Mirage of Conflict between Science and Religion (2009); and the second enlarged edition of his 1974 book, Science and Creation: From Eternal Cycles to an Oscillating Universe (2016). *Jaki also published studies of figures whose life and work most impressed him personally. These include three books (1984, 1988, 1991) on the Catholic physicist and historian of cosmology, Pierre Duhem, author of the ten-volume Système du Monde, and studies of English converts to Catholicism, John Henry, Cardinal Newman (2001, 2004, 2007) and G. K. Chesterton (1986, new ed., 2001). *Among Jaki's books not mentioned by Giostra but of interest to readers of this journal are The Origin of Science and the Science of its Origin (1979), Angels, Apes, and Men (1988), and Miracles and Physics (2004). For a complete Jaki bibliography, see http://www.sljaki.com/. *No translator is identified in the book under review; my guess is that Giostra, an Italian, was writing in English. Although generally clear and correct, the book contains enough small errors and infelicities to suggest that the services of a professional translator were not used. Not counting blank, title, and contents pages, this book has but 128 pages, including lots of block quotations. *For those unfamiliar with Jaki's work and not too interested in detailed studies in the history and philosophy of science and religion, this introduction is a decent start--and perhaps an end point as well. I strongly encourage curious readers to consult Jaki's own books, including his intellectual autobiography A Mind's Matter (2002). For other scholarly English-language perspectives on his work, see Paul Haffner, Creation and Scientific Creativity: A Study in the Thought of S. L. Jaki (2nd ed., 2009); Science and Orthodoxy [special issue of the Saint Austin Review on Jaki], vol. 14, no. 3 (2014); and Paul Carr and Paul Arveson, eds., Stanley Jaki Foundation International Congress 2015 (2020). *Reviewed by Paul Fayter, a retired pastor and historian of Victorian science and theology, who lives in Hamilton, Ontario.
APA, Harvard, Vancouver, ISO, and other styles
19

Nesrine, Lenchi, Kebbouche Salima, Khelfaoui Mohamed Lamine, Laddada Belaid, BKhemili Souad, Gana Mohamed Lamine, Akmoussi Sihem, and Ferioune Imène. "Phylogenetic characterization and screening of halophilic bacteria from Algerian salt lake for the production of biosurfactant and enzymes." World Journal of Biology and Biotechnology 5, no. 2 (August 15, 2020): 1. http://dx.doi.org/10.33865/wjb.005.02.0294.

Full text
Abstract:
Environments containing significant concentration of NaCl such as salt lakes harbor extremophiles microorganisms which have a great biotechnology interest. To explore the diversity of Bacteria in Chott Tinsilt (Algeria), an isolation program was performed. Water samples were collected from the saltern during the pre-salt harvesting phase. This Chott is high in salt (22.47% (w/v). Seven halophiles Bacteria were selected for further characterization. The isolated strains were able to grow optimally in media with 10–25% (w/v) total salts. Molecular identification of the isolates was performed by sequencing the 16S rRNA gene. It showed that these cultured isolates included members belonging to the Halomonas, Staphylococcus, Salinivibrio, Planococcus and Halobacillus genera with less than 98% of similarity with their closest phylogenetic relative. The halophilic bacterial isolates were also characterized for the production of biosurfactant and industrially important enzymes. Most isolates produced hydrolases and biosurfactants at high salt concentration. In fact, this is the first report on bacterial strains (A4 and B4) which were a good biosurfactant and coagulase producer at 20% and 25% ((w/v)) NaCl. In addition, the biosurfactant produced by the strain B4 at high salinity (25%) was also stable at high temperature (30-100°C) and high alkalinity (pH 11).Key word: Salt Lake, Bacteria, biosurfactant, Chott, halophiles, hydrolases, 16S rRNAINTRODUCTIONSaline lakes cover approximately 10% of the Earth’s surface area. The microbial populations of many hypersaline environments have already been studied in different geographical regions such as Great Salt Lake (USA), Dead Sea (Israel), Wadi Natrun Lake (Egypt), Lake Magadi (Kenya), Soda Lake (Antarctica) and Big Soda Lake and Mono Lake (California). Hypersaline regions differ from each other in terms of geographical location, salt concentration and chemical composition, which determine the nature of inhabitant microorganisms (Gupta et al., 2015). Then low taxonomic diversity is common to all these saline environments (Oren et al., 1993). Halophiles are found in nearly all major microbial clades, including prokaryotic (Bacteria and Archaea) and eukaryotic forms (DasSarma and Arora, 2001). They are classified as slight halophiles when they grow optimally at 0.2–0.85 M (2–5%) NaCl, as moderate halophiles when they grow at 0.85–3.4 M (5–20%) NaCl, and as extreme halophiles when they grow at 3.4–5.1 M (20–30%) NaCl. Hyper saline environments are inhabited by extremely halophilic and halotolerant microorganisms such as Halobacillus sp, Halobacterium sp., Haloarcula sp., Salinibacter ruber , Haloferax sp and Bacillus spp. (Solomon and Viswalingam, 2013). There is a tremendous demand for halophilic bacteria due to their biotechnological importance as sources of halophilic enzymes. Enzymes derived from halophiles are endowed with unique structural features and catalytic power to sustain the metabolic and physiological processes under high salt conditions. Some of these enzymes have been reported to be active and stable under more than one extreme condition (Karan and Khare, 2010). Applications are being considered in a range of industries such as food processing, washing, biosynthetic processes and environmental bioremediation. Halophilic proteases are widely used in the detergent and food industries (DasSarma and Arora, 2001). However, esterases and lipases have also been useful in laundry detergents for the removal of oil stains and are widely used as biocatalysts because of their ability to produce pure compounds. Likewise, amylases are used industrially in the first step of the production of high fructose corn syrup (hydrolysis of corn starch). They are also used in the textile industry in the de-sizing process and added to laundry detergents. Furthermore, for the environmental applications, the use of halophiles for bioremediation and biodegradation of various materials from industrial effluents to soil contaminants and accidental spills are being widely explored. In addition to enzymes, halophilic / halotolerants microorganisms living in saline environments, offer another potential applications in various fields of biotechnology like the production of biosurfactant. Biosurfactants are amphiphilic compounds synthesized from plants and microorganisms. They reduce surface tension and interfacial tension between individual molecules at the surface and interface respectively (Akbari et al., 2018). Comparing to the chemical surfactant, biosurfactant are promising alternative molecules due to their low toxicity, high biodegradability, environmental capability, mild production conditions, lower critical micelle concentration, higher selectivity, availability of resources and ability to function in wide ranges of pH, temperature and salinity (Rocha et al., 1992). They are used in various industries which include pharmaceuticals, petroleum, food, detergents, cosmetics, paints, paper products and water treatment (Akbari et al., 2018). The search for biosurfactants in extremophiles is particularly promising since these biomolecules can adapt and be stable in the harsh environments in which they are to be applied in biotechnology.OBJECTIVESEastern Algeria features numerous ecosystems including hypersaline environments, which are an important source of salt for food. The microbial diversity in Chott Tinsilt, a shallow Salt Lake with more than 200g/L salt concentration and a superficies of 2.154 Ha, has never yet been studied. The purpose of this research was to chemically analyse water samples collected from the Chott, isolate novel extremely or moderate halophilic Bacteria, and examine their phenotypic and phylogenetic characteristics with a view to screening for biosurfactants and enzymes of industrial interest.MATERIALS AND METHODSStudy area: The area is at 5 km of the Commune of Souk-Naâmane and 17 km in the South of the town of Aïn-Melila. This area skirts the trunk road 3 serving Constantine and Batna and the railway Constantine-Biskra. It is part the administrative jurisdiction of the Wilaya of Oum El Bouaghi. The Chott belongs to the wetlands of the High Plains of Constantine with a depth varying rather regularly without never exceeding 0.5 meter. Its length extends on 4 km with a width of 2.5 km (figure 1).Water samples and physico-chemical analysis: In February 2013, water samples were collected from various places at the Chott Tinsilt using Global Positioning System (GPS) coordinates of 35°53’14” N lat. and 06°28’44”E long. Samples were collected randomly in sterile polythene bags and transported immediately to the laboratory for isolation of halophilic microorganisms. All samples were treated within 24 h after collection. Temperature, pH and salinity were measured in situ using a multi-parameter probe (Hanna Instruments, Smithfield, RI, USA). The analytical methods used in this study to measure ions concentration (Ca2+, Mg2+, Fe2+, Na+, K+, Cl−, HCO3−, SO42−) were based on 4500-S-2 F standard methods described elsewhere (Association et al., 1920).Isolation of halophilic bacteria from water sample: The media (M1) used in the present study contain (g/L): 2.0 g of KCl, 100.0/200.0 g of NaCl, 1.0 g of MgSO4.7HO2, 3.0 g of Sodium Citrate, 0.36 g of MnCl2, 10.0 g of yeast extract and 15.0 g agar. The pH was adjusted to 8.0. Different dilutions of water samples were added to the above medium and incubated at 30°C during 2–7 days or more depending on growth. Appearance and growth of halophilic bacteria were monitored regularly. The growth was diluted 10 times and plated on complete medium agar (g/L): glucose 10.0; peptone 5.0; yeast extract 5.0; KH2PO4 5.0; agar 30.0; and NaCl 100.0/200.0. Resultant colonies were purified by repeated streaking on complete media agar. The pure cultures were preserved in 20% glycerol vials and stored at −80°C for long-term preservation.Biochemical characterisation of halophilic bacterial isolates: Bacterial isolates were studied for Gram’s reaction, cell morphology and pigmentation. Enzymatic assays (catalase, oxidase, nitrate reductase and urease), and assays for fermentation of lactose and mannitol were done as described by Smibert (1994).Optimization of growth conditions: Temperature, pH, and salt concentration were optimized for the growth of halophilic bacterial isolates. These growth parameters were studied quantitatively by growing the bacterial isolates in M1 medium with shaking at 200 rpm and measuring the cell density at 600 nm after 8 days of incubation. To study the effect of NaCl on the growth, bacterial isolates were inoculated on M1 medium supplemented with different concentration of NaCl: 1%-35% (w/v). The effect of pH on the growth of halophilic bacterial strains was studied by inoculating isolates on above described growth media containing NaCl and adjusted to acidic pH of 5 and 6 by using 1N HCl and alkaline pH of 8, 9, 10, 11 and 12 using 5N NaOH. The effect of temperature was studied by culturing the bacterial isolates in M1 medium at different temperatures of incubation (4°C–55°C).Screening of halophilic bacteria for hydrolytic enzymes: Hydrolase producing bacteria among the isolates were screened by plate assay on starch, tributyrin, gelatin and DNA agar plates respectively for amylase, lipase, protease and DNAse activities. Amylolytic activity of the cultures was screened on starch nutrient agar plates containing g/L: starch 10.0; peptone 5.0; yeast extract 3.0; agar 30.0; NaCl 100.0/250.0. The pH was 7.0. After incubation at 30 ºC for 7 days, the zone of clearance was determined by flooding the plates with iodine solution. The potential amylase producers were selected based on ratio of zone of clearance diameter to colony diameter. Lipase activity of the cultures was screened on tributyrin nutrient agar plates containing 1% (v/v) of tributyrin. Isolates that showed clear zones of tributyrin hydrolysis were identified as lipase producing bacteria. Proteolytic activity of the isolates was similarly screened on gelatin nutrient agar plates containing 10.0 g/L of gelatin. The isolates showing zones of gelatin clearance upon treatment with acidic mercuric chloride were selected and designated as protease producing bacteria. The presence of DNAse activity on plates was determined on DNAse test agar (BBL) containing 10%-25% (w/v) total salt. After incubation for 7days, the plates were flooded with 1N HCl solution. Clear halos around the colonies indicated DNAse activity (Jeffries et al., 1957).Milk clotting activity (coagulase activity) of the isolates was also determined following the procedure described (Berridge, 1952). Skim milk powder was reconstituted in 10 mM aqueous CaCl2 (pH 6.5) to a final concentration of 0.12 kg/L. Enzyme extracts were added at a rate of 0.1 mL per mL of milk. The coagulation point was determined by manual rotating of the test tube periodically, at short time intervals, and checking for visible clot formation.Screening of halophilic bacteria for biosurfactant production. Oil spread Assay: The Petridis base was filled with 50 mL of distilled water. On the water surface, 20μL of diesel and 10μl of culture were added respectively. The culture was introduced at different spots on the diesel, which is coated on the water surface. The occurrence of a clear zone was an indicator of positive result (Morikawa et al., 2000). The diameter of the oil expelling circles was measured by slide caliber (with a degree of accuracy of 0.02 mm).Surface tension and emulsification index (E24): Isolates were cultivated at 30 °C for 7 days on the enrichment medium containing 10-25% NaCl and diesel oil as the sole carbon source. The medium was centrifuged (7000 rpm for 20 min) and the surface tension of the cell-free culture broth was measured with a TS90000 surface tensiometer (Nima, Coventry, England) as a qualitative indicator of biosurfactant production. The culture broth was collected with a Pasteur pipette to remove the non-emulsified hydrocarbons. The emulsifying capacity was evaluated by an emulsification index (E24). The E24 of culture samples was determined by adding 2 mL of diesel oil to the same amount of culture, mixed for 2 min with a vortex, and allowed to stand for 24 h. E24 index is defined as the percentage of height of emulsified layer (mm) divided by the total height of the liquid column (mm).Biosurfactant stability studies : After growth on diesel oil as sole source of carbone, cultures supernatant obtained after centrifugation at 6,000 rpm for 15 min were considered as the source of crude biosurfactant. Its stability was determined by subjecting the culture supernatant to various temperature ranges (30, 40, 50, 60, 70, 80 and 100 °C) for 30 min then cooled to room temperature. Similarly, the effect of different pH (2–11) on the activity of the biosurfactant was tested. The activity of the biosurfactant was investigated by measuring the emulsification index (El-Sersy, 2012).Molecular identification of potential strains. DNA extraction and PCR amplification of 16S rDNA: Total cellular DNA was extracted from strains and purified as described by Sambrook et al. (1989). DNA was purified using Geneclean® Turbo (Q-BIO gene, Carlsbad, CA, USA) before use as a template in polymerase chain reaction (PCR) amplification. For the 16S rDNA gene sequence, the purified DNA was amplified using a universal primer set, forward primer (27f; 5′-AGA GTT TGA TCM TGG CTC AG) and a reverse primer (1492r; 5′-TAC GGY TAC CTT GTT ACG ACT T) (Lane, 1991). Agarose gel electrophoresis confirmed the amplification product as a 1400-bp DNA fragment.16S rDNA sequencing and Phylogenic analysis: Amplicons generated using primer pair 27f-1492r was sequenced using an automatic sequencer system at Macrogene Company (Seoul, Korea). The sequences were compared with those of the NCBI BLAST GenBank nucleotide sequence databases. Phylogenetic trees were constructed by the neighbor-joining method using MEGA version 5.05 software (Tamura et al., 2011). Bootstrap resembling analysis for 1,000 replicates was performed to estimate the confidence of tree topologies.Nucleotide sequence accession numbers: The nucleotide sequences reported in this work have been deposited in the EMBL Nucleotide Sequence Database. The accession numbers are represented in table 5.Statistics: All experiments were conducted in triplicates. Results were evaluated for statistical significance using ANOVA.RESULTSPhysico-chemical parameters of the collected water samples: The physicochemical properties of the collected water samples are reported in table 1. At the time of sampling, the temperature was 10.6°C and pH 7.89. The salinity of the sample, as determined in situ, was 224.70 g/L (22,47% (w/v)). Chemical analysis of water sample indicated that Na +and Cl- were the most abundant ions (table 1). SO4-2 and Mg+2 was present in much smaller amounts compared to Na +and Cl- concentration. Low levels of calcium, potassium and bicarbonate were also detected, often at less than 1 g/L.Characterization of isolates. Morphological and biochemical characteristic feature of halophilic bacterial isolates: Among 52 strains isolated from water of Chott Tinsilt, seven distinct bacteria (A1, A2, A3, A4, B1, B4 and B5) were chosen for further characterization (table 2). The colour of the isolates varied from beige, pale yellow, yellowish and orange. The bacterial isolates A1, A2, A4, B1 and B5 were rod shaped and gram negative (except B5), whereas A3 and B4 were cocci and gram positive. All strains were oxidase and catalase positive except for B1. Nitrate reductase and urease activities were observed in all the bacterial isolates, except B4. All the bacterial isolates were negative for H2S formation. B5 was the only strain positive for mannitol fermentation (table 2).We isolated halophilic bacteria on growth medium with NaCl supplementation at pH 7 and temperature of 30°C. We studied the effect of NaCl, temperature and pH on the growth of bacterial isolates. All the isolates exhibited growth only in the presence of NaCl indicating that these strains are halophilic. The optimum growth of isolates A3 and B1 was observed in the presence of 10% NaCl, whereas it was 15% NaCl for A1, A2 and B5. A4 and B4 showed optimum growth in the presence of 20% and 25% NaCl respectively. A4, B4 and B5 strains can tolerate up to 35% NaCl.The isolate B1 showed growth in medium supplemented with 10% NaCl and pH range of 7–10. The optimum pH for the growth B1 was 9 and they did not show any detectable growth at or below pH 6 (table 2), which indicates the alkaliphilic nature of B1 isolate. The bacterial isolates A1, A2 and A4 exhibited growth in the range of pH 6–10, while A3 and B4 did not show any growth at pH greater than 8. The optimum pH for growth of all strains (except B1) was pH 7.0 (table 2). These results indicate that A1, A2, A3, A4, B4 and B5 are neutrophilic in nature. All the bacterial isolates exhibited optimal growth at 30°C and no detectable growth at 55°C. Also, detectable growth of isolates A1, A2 and A4 was observed at 4°C. However, none of the bacterial strains could grow below 4°C and above 50°C (table 2).Screening of the halophilic enzymes: To characterize the diversity of halophiles able to produce hydrolytic enzymes among the population of microorganisms inhabiting the hypersaline habitats of East Algeria (Chott Tinsilt), a screening was performed. As described in Materials and Methods, samples were plated on solid media containing 10%-25% (w/v) of total salts and different substrates for the detection of amylase, protease, lipase and DNAse activities. However, coagulase activity was determined in liquid medium using milk as substrate (figure 3). Distributions of hydrolytic activity among the isolates are summarized in table 4.From the seven bacterial isolates, four strains A1, A2, A4 and B5 showed combined hydrolytic activities. They were positive for gelatinase, lipase and coagulase. A3 strain showed gelatinase and lipase activities. DNAse activities were detected with A1, A4, B1 and B5 isolates. B4 presented lipase and coagulase activity. Surprisingly, no amylase activity was detected among all the isolates.Screening for biosurfactant producing isolates: Oil spread assay: The results showed that all the strains could produce notable (>4 cm diameter) oil expelling circles (ranging from 4.11 cm to 4.67 cm). The average diameter for strain B5 was 4.67 cm, significantly (P < 0.05) higher than for the other strains.Surface tension and emulsification index (E24): The assimilation of hydrocarbons as the sole sources of carbon by the isolate strains led to the production of biosurfactants indicated by the emulsification index and the lowering of the surface tension of cell-free supernatant. Based on rapid growth on media containing diesel oil as sole carbon source, the seven isolates were tested for biosurfactant production and emulsification activity. The obtained values of the surface tension measurements as well as the emulsification index (E24) are shown in table 3. The highest reduction of surface tension was achieved with B5 and A3 isolates with values of 25.3 mN m−1 and 28.1 mN m−1 respectively. The emulsifying capacity evaluated by the E24 emulsification index was highest in the culture of isolate B4 (78%), B5 (77%) and A3 (76%) as shown in table 3 and figure 2. These emulsions were stable even after 4 months. The bacteria with emulsification indices higher than 50 % and/or reduction in the surface tension (under 30 mN/m) have been defined as potential biosurfactant producers. Based on surface tension and the E24 index results, isolates B5, B4, A3 and A4 are the best candidates for biosurfactant production. It is important to note that, strains B4 and A4 produce biosurfactant in medium containing respectively 25% and 20% (w/v) NaCl.Stability of biosurfactant activities: The applicability of biosurfactants in several biotechnological fields depends on their stability at different environmental conditions (temperatures, pH and NaCl). For this study, the strain B4 appear very interesting (It can produce biosurfactant at 25 % NaCl) and was choosen for futher analysis for biosurfactant stability. The effects of temperature and pH on the biosurfactant production by the strain B4 are shown in figure 4.biosurfactant in medium containing respectively 25% and 20% (w/v) NaCl.Stability of biosurfactant activities: The applicability of biosurfactants in several biotechnological fields depends on their stability at different environmental conditions (temperatures, pH and NaCl). For this study, the strain B4 appear very interesting (It can produce biosurfactant at 25 % NaCl) and was chosen for further analysis for biosurfactant stability. The effects of temperature and pH on the biosurfactant production by the strain B4 are shown in figure 4. The biosurfactant produced by this strain was shown to be thermostable giving an E-24 Index value greater than 78% (figure 4A). Heating of the biosurfactant to 100 °C caused no significant effect on the biosurfactant performance. Therefore, the surface activity of the crude biosurfactant supernatant remained relatively stable to pH changes between pH 6 and 11. At pH 11, the value of E24 showed almost 76% activity, whereas below pH 6 the activity was decreased up to 40% (figure 4A). The decreases of the emulsification activity by decreasing the pH value from basic to an acidic region; may be due to partial precipitation of the biosurfactant. This result indicated that biosurfactant produced by strain B4 show higher stability at alkaline than in acidic conditions.Molecular identification and phylogenies of potential isolates: To identify halophilic bacterial isolates, the 16S rDNA gene was amplified using gene-specific primers. A PCR product of ≈ 1.3 kb was detected in all the seven isolates. The 16S rDNA amplicons of each bacterial isolate was sequenced on both strands using 27F and 1492R primers. The complete nucleotide sequence of 1336,1374, 1377,1313, 1305,1308 and 1273 bp sequences were obtained from A1, A2, A3, A4, B1, B4 and B5 isolates respectively, and subjected to BLAST analysis. The 16S rDNA sequence analysis showed that the isolated strains belong to the genera Halomonas, Staphylococcus, Salinivibrio, Planococcus and Halobacillus as shown in table 5. The halophilic isolates A2 and A4 showed 97% similarity with the Halomonas variabilis strain GSP3 (accession no. AY505527) and the Halomonas sp. M59 (accession no. AM229319), respectively. As for A1, it showed 96% similarity with the Halomonas venusta strain GSP24 (accession no. AY553074). B1 and B4 showed for their part 96% similarity with the Salinivibrio costicola subsp. alcaliphilus strain 18AG DSM4743 (accession no. NR_042255) and the Planococcus citreus (accession no. JX122551), respectively. The bacterial isolate B5 showed 98% sequence similarity with the Halobacillus trueperi (accession no. HG931926), As for A3, it showed only 95% similarity with the Staphylococcus arlettae (accession no. KR047785). The 16S rDNA nucleotide sequences of all the seven halophilic bacterial strains have been submitted to the NCBI GenBank database under the accession number presented in table 5. The phylogenetic association of the isolates is shown in figure 5.DICUSSIONThe physicochemical properties of the collected water samples indicated that this water was relatively neutral (pH 7.89) similar to the Dead Sea and the Great Salt Lake (USA) and in contrast to the more basic lakes such as Lake Wadi Natrun (Egypt) (pH 11) and El Golea Salt Lake (Algeria) (pH 9). The salinity of the sample was 224.70 g/L (22,47% (w/v). This range of salinity (20-30%) for Chott Tinsilt is comparable to a number of well characterized hypersaline ecosystems including both natural and man-made habitats, such as the Great Salt Lake (USA) and solar salterns of Puerto Rico. Thus, Chott Tinsilt is a hypersaline environment, i.e. environments with salt concentrations well above that of seawater. Chemical analysis of water sample indicated that Na +and Cl- were the most abundant ions, as in most hypersaline ecosystems (with some exceptions such as the Dead Sea). These chemical water characteristics were consistent with the previously reported data in other hypersaline ecosystems (DasSarma and Arora, 2001; Oren, 2002; Hacěne et al., 2004). Among 52 strains isolated from this Chott, seven distinct bacteria (A1, A2, A3, A4, B1, B4 and B5) were chosen for phenotypique, genotypique and phylogenetique characterization.The 16S rDNA sequence analysis showed that the isolated strains belong to the genera Halomonas, Staphylococcus, Salinivibrio, Planococcus and Halobacillus. Genera obtained in the present study are commonly occurring in various saline habitats across the globe. Staphylococci have the ability to grow in a wide range of salt concentrations (Graham and Wilkinson, 1992; Morikawa et al., 2009; Roohi et al., 2014). For example, in Pakistan, Staphylococcus strains were isolated from various salt samples during the study conducted by Roohi et al. (2014) and these results agreed with previous reports. Halomonas, halophilic and/or halotolerant Gram-negative bacteria are typically found in saline environments (Kim et al., 2013). The presence of Planococcus and Halobacillus has been reported in studies about hypersaline lakes; like La Sal del Rey (USA) (Phillips et al., 2012) and Great Salt Lake (Spring et al., 1996), respectively. The Salinivibrio costicola was a representative model for studies on osmoregulatory and other physiological mechanisms of moderately halophilic bacteria (Oren, 2006).However, it is interesting to note that all strains shared less than 98.7% identity (the usual species cut-off proposed by Yarza et al. (2014) with their closest phylogenetic relative, suggesting that they could be considered as new species. Phenotypic, genetic and phylogenetic analyses have been suggested for the complete identification of these strains. Theses bacterial strains were tested for the production of industrially important enzymes (Amylase, protease, lipase, DNAse and coagulase). These isolates are good candidates as sources of novel enzymes with biotechnological potential as they can be used in different industrial processes at high salt concentration (up to 25% NaCl for B4). Prominent amylase, lipase, protease and DNAase activities have been reported from different hypersaline environments across the globe; e.g., Spain (Sánchez‐Porro et al., 2003), Iran (Rohban et al., 2009), Tunisia (Baati et al., 2010) and India (Gupta et al., 2016). However, to the best of our knowledge, the coagulase activity has never been detected in extreme halophilic bacteria. Isolation and characterization of crude enzymes (especially coagulase) to investigate their properties and stability are in progress.The finding of novel enzymes with optimal activities at various ranges of salt concentrations is of great importance. Besides being intrinsically stable and active at high salt concentrations, halophilic and halotolerant enzymes offer great opportunities in biotechnological applications, such as environmental bioremediation (marine, oilfiel) and food processing. The bacterial isolates were also characterized for production of biosurfactants by oil-spread assay, measurement of surface tension and emulsification index (E24). There are few reports on biosurfactant producers in hypersaline environments and in recent years, there has been a greater increase in interest and importance in halophilic bacteria for biomolecules (Donio et al., 2013; Sarafin et al., 2014). Halophiles, which have a unique lipid composition, may have an important role to play as surface-active agents. The archae bacterial ether-linked phytanyl membrane lipid of the extremely halophilic bacteria has been shown to have surfactant properties (Post and Collins, 1982). Yakimov et al. (1995) reported the production of biosurfactant by a halotolerant Bacillus licheniformis strain BAS 50 which was able to produce a lipopeptide surfactant when cultured at salinities up to 13% NaCl. From solar salt, Halomonas sp. BS4 and Kocuria marina BS-15 were found to be able to produce biosurfactant when cultured at salinities of 8% and 10% NaCl respectively (Donio et al., 2013; Sarafin et al., 2014). In the present work, strains B4 and A4 produce biosurfactant in medium containing respectively 25% and 20% NaCl. To our knowledge, this is the first report on biosurfactant production by bacteria under such salt concentration. Biosurfactants have a wide variety of industrial and environmental applications (Akbari et al., 2018) but their applicability depends on their stability at different environmental conditions. The strain B4 which can produce biosurfactant at 25% NaCl showed good stability in alkaline pH and at a temperature range of 30°C-100°C. Due to the enormous utilization of biosurfactant in detergent manufacture the choice of alkaline biosurfactant is researched (Elazzazy et al., 2015). On the other hand, the interesting finding was the thermostability of the produced biosurfactant even after heat treatment (100°C for 30 min) which suggests the use of this biosurfactant in industries where heating is of a paramount importance (Khopade et al., 2012). To date, more attention has been focused on biosurfactant producing bacteria under extreme conditions for industrial and commercial usefulness. In fact, the biosurfactant produce by strain B4 have promising usefulness in pharmaceutical, cosmetics and food industries and for bioremediation in marine environment and Microbial enhanced oil recovery (MEOR) where the salinity, temperature and pH are high.CONCLUSIONThis is the first study on the culturable halophilic bacteria community inhabiting Chott Tinsilt in Eastern Algeria. Different genera of halotolerant bacteria with different phylogeneticaly characteristics have been isolated from this Chott. Culturing of bacteria and their molecular analysis provides an opportunity to have a wide range of cultured microorganisms from extreme habitats like hypersaline environments. Enzymes produced by halophilic bacteria show interesting properties like their ability to remain functional in extreme conditions, such as high temperatures, wide range of pH, and high salt concentrations. These enzymes have great economical potential in industrial, agricultural, chemical, pharmaceutical, and biotechnological applications. Thus, the halophiles isolated from Chott Tinsilt offer an important potential for application in microbial and enzyme biotechnology. In addition, these halo bacterial biosurfactants producers isolated from this Chott will help to develop more valuable eco-friendly products to the pharmacological and food industries and will be usefulness for bioremediation in marine environment and petroleum industry.ACKNOWLEDGMENTSOur thanks to Professor Abdelhamid Zoubir for proofreading the English composition of the present paper.CONFLICT OF INTERESTThe authors declare that they have no conflict of interest.Akbari, S., N. H. Abdurahman, R. M. Yunus, F. Fayaz and O. R. Alara, 2018. Biosurfactants—a new frontier for social and environmental safety: A mini review. Biotechnology research innovation, 2(1): 81-90.Association, A. P. H., A. W. W. Association, W. P. C. Federation and W. E. Federation, 1920. Standard methods for the examination of water and wastewater. American Public Health Association.Baati, H., R. Amdouni, N. Gharsallah, A. Sghir and E. Ammar, 2010. Isolation and characterization of moderately halophilic bacteria from tunisian solar saltern. Current microbiology, 60(3): 157-161.Berridge, N., 1952. Some observations on the determination of the activity of rennet. Analyst, 77(911): 57b-62.DasSarma, S. and P. Arora, 2001. Halophiles. Encyclopedia of life sciences. Nature publishishing group: 1-9.Donio, M. B. S., F. A. Ronica, V. T. Viji, S. Velmurugan, J. S. C. A. Jenifer, M. Michaelbabu, P. Dhar and T. Citarasu, 2013. Halomonas sp. Bs4, a biosurfactant producing halophilic bacterium isolated from solar salt works in India and their biomedical importance. SpringerPlus, 2(1): 149.El-Sersy, N. A., 2012. Plackett-burman design to optimize biosurfactant production by marine Bacillus subtilis n10. Roman biotechnol lett, 17(2): 7049-7064.Elazzazy, A. M., T. Abdelmoneim and O. Almaghrabi, 2015. Isolation and characterization of biosurfactant production under extreme environmental conditions by alkali-halo-thermophilic bacteria from Saudi Arabia. Saudi journal of biological Sciences, 22(4): 466-475.Graham, J. E. and B. Wilkinson, 1992. Staphylococcus aureus osmoregulation: Roles for choline, glycine betaine, proline, and taurine. Journal of bacteriology, 174(8): 2711-2716.Gupta, S., P. Sharma, K. Dev and A. Sourirajan, 2016. Halophilic bacteria of lunsu produce an array of industrially important enzymes with salt tolerant activity. Biochemistry research international, 1: 1-10.Gupta, S., P. Sharma, K. Dev, M. Srivastava and A. Sourirajan, 2015. A diverse group of halophilic bacteria exist in lunsu, a natural salt water body of Himachal Pradesh, India. SpringerPlus 4(1): 274.Hacěne, H., F. Rafa, N. Chebhouni, S. Boutaiba, T. Bhatnagar, J. C. Baratti and B. Ollivier, 2004. Biodiversity of prokaryotic microflora in el golea salt lake, Algerian Sahara. Journal of arid environments, 58(3): 273-284.Jeffries, C. D., D. F. Holtman and D. G. Guse, 1957. Rapid method for determining the activity of microorgan-isms on nucleic acids. Journal of bacteriology, 73(4): 590.Karan, R. and S. Khare, 2010. Purification and characterization of a solvent‐stable protease from Geomicrobium sp. Emb2. Environmental technology, 31(10): 1061-1072.Khopade, A., R. Biao, X. Liu, K. Mahadik, L. Zhang and C. Kokare, 2012. Production and stability studies of the biosurfactant isolated from marine Nocardiopsis sp. B4. Desalination, 3: 198-204.Kim, K. K., J.-S. Lee and D. A. Stevens, 2013. Microbiology and epidemiology of Halomonas species. Future microbiology, 8(12): 1559-1573.Lane, D., 1991. 16s/23s rRNA sequencing in nucleic acid techniques in bacterial systematics. Stackebrandt e., editor;, and goodfellow m., editor. Chichester, UK: John Wiley & Sons.Morikawa, K., R. L. Ohniwa, T. Ohta, Y. Tanaka, K. Takeyasu and T. Msadek, 2009. Adaptation beyond the stress response: Cell structure dynamics and population heterogeneity in Staphylococcus aureus. Microbes environments, 25: 75-82.Morikawa, M., Y. Hirata and T. J. B. e. B. A.-M. Imanaka, 2000. A study on the structure–function relationship of lipopeptide biosurfactants. Biochimica et biophysica acta, 1488(3): 211-218.Oren, A., 2002. Diversity of halophilic microorganisms: Environments, phylogeny, physiology, and applications. Journal of industrial microbiology biotechnology, 28(1): 56-63.Oren, A., 2006. Halophilic microorganisms and their environments. Springer science & business media.Oren, A., R. Vreeland and L. Hochstein, 1993. Ecology of extremely halophilic microorganisms. The biology of halophilic bacteria, 2(1): 1-8.Phillips, K., F. Zaidan, O. R. Elizondo and K. L. Lowe, 2012. Phenotypic characterization and 16s rDNA identification of culturable non-obligate halophilic bacterial communities from a hypersaline lake, la sal del rey, in extreme south texas (USA). Aquatic biosystems, 8(1): 1-5.Post, F. and N. Collins, 1982. A preliminary investigation of the membrane lipid of Halobacterium halobium as a food additive 1. Journal of food biochemistry, 6(1): 25-38.Rocha, C., F. San-Blas, G. San-Blas and L. Vierma, 1992. Biosurfactant production by two isolates of Pseudomonas aeruginosa. World Journal of microbiology biotechnology, 8(2): 125-128.Rohban, R., M. A. Amoozegar and A. Ventosa, 2009. Screening and isolation of halophilic bacteria producing extracellular hydrolyses from howz soltan lake, Iran. Journal of industrial microbiology biotechnology, 36(3): 333-340.Roohi, A., I. Ahmed, N. Khalid, M. Iqbal and M. Jamil, 2014. Isolation and phylogenetic identification of halotolerant/halophilic bacteria from the salt mines of Karak, Pakistan. International journal of agricultural and biology, 16: 564-570.Sambrook, J., E. F. Fritsch and T. Maniatis, 1989. Molecular cloning: A laboratory manual, 2nd edn. Cold spring harbor laboratory, cold spring harbor, New York.Sánchez‐Porro, C., S. Martin, E. Mellado and A. Ventosa, 2003. Diversity of moderately halophilic bacteria producing extracellular hydrolytic enzymes. Journal of applied microbiology, 94(2): 295-300.Sarafin, Y., M. B. S. Donio, S. Velmurugan, M. Michaelbabu and T. Citarasu, 2014. Kocuria marina bs-15 a biosurfactant producing halophilic bacteria isolated from solar salt works in India. Saudi journal of biological sciences, 21(6): 511-519.Smibert, R., 1994. Phenotypic characterization. In methods for general and molecular bacteriology. American society for microbiology: 611-651.Solomon, E. and K. J. I. Viswalingam, 2013. Isolation, characterization of halotolerant bacteria and its biotechnological potentials. International journal scientific research paper publication sites, 4: 1-7.Spring, S., W. Ludwig, M. Marquez, A. Ventosa and K.-H. Schleifer, 1996. Halobacillus gen. Nov., with descriptions of Halobacillus litoralis sp. Nov. and Halobacillus trueperi sp. Nov., and transfer of Sporosarcina halophila to Halobacillus halophilus comb. Nov. International journal of systematic evolutionary microbiology, 46(2): 492-496.Tamura, K., D. Peterson, N. Peterson, G. Stecher, M. Nei and S. Kumar, 2011. Mega5: Molecular evolutionary genetics analysis using maximum likelihood, evolutionary distance, and maximum parsimony methods. Molecular biology evolution, 28(10): 2731-2739.Yakimov, M. M., K. N. Timmis, V. Wray and H. L. Fredrickson, 1995. Characterization of a new lipopeptide surfactant produced by thermotolerant and halotolerant subsurface Bacillus licheniformis bas50. Applied and environmental microbiology, 61(5): 1706-1713.Yarza, P., P. Yilmaz, E. Pruesse, F. O. Glöckner, W. Ludwig, K.-H. Schleifer, W. B. Whitman, J. Euzéby, R. Amann and R. Rosselló-Móra, 2014. Uniting the classification of cultured and uncultured bacteria and archaea using 16s rRNA gene sequences. Nature reviews microbiology, 12(9): 635-645
APA, Harvard, Vancouver, ISO, and other styles
20

"Erratum." Journal of Documentation 60, no. 6 (December 1, 2004): 597–600. http://dx.doi.org/10.1108/00220410410568106.

Full text
Abstract:
This article has been withdrawn as it was published elsewhere and accidentally duplicated. The original article can be seen here: 10.1108/eb026418. When citing the article, please cite: A.J. MEADOWS, (1967), “THE CITATION CHARACTERISTICS OF ASTRONOMICAL RESEARCH LITERATURE”, Journal of Documentation, Vol. 23 Iss: 1, pp. 28 - 33.
APA, Harvard, Vancouver, ISO, and other styles
21

Ramašauskas, Olegas, Ilona Rupšienė, and Mantas Kazlauskas. "Digital filters creation of seabed image processing." Lietuvos matematikos rinkinys 56 (December 20, 2015). http://dx.doi.org/10.15388/lmr.b.2015.21.

Full text
Abstract:
Nowadays visual information is extracted using a variety of physical methods and cannot always be easily perceived by the human eye, properly recognized and classified. Such large amounts of information provided by the modern image-making equipment is difficult and sometimes impossible objectively evaluate. Research of digital images carried out at the Klaipėda University with a focus on marine research topic. The combination of new underwater technology as remotely operating vehicles, high-resolution video imagery, and seafloor mosaics creating provides new opportunities for marine geological or biological studies. While these underwater techniques are now well-engineered, there is still a lack of methods for the automatic analysis of the acquired image data. In this paper, the video mosaic quality and processing problems discussed. Believes that the versatility of abstract techniques to tailor the fields of biomedical sciences, applied robotics and elsewhere. This could be listed as a main purpose of presented work.
APA, Harvard, Vancouver, ISO, and other styles
22

Beenken, Ludwig, Sophie Stroheker, Vivanne Dubach, Markus Schlegel, Valentin Queloz, and Andrin Gross. "Microstrobilinia castrans, a new genus and species of the Sclerotiniaceae parasitizing pollen cones of Picea spp." Mycological Progress 22, no. 2 (January 27, 2023). http://dx.doi.org/10.1007/s11557-023-01865-w.

Full text
Abstract:
AbstractThe fungal pathogens of spruce are well known in Europe and elsewhere. Therefore, it was surprising to discover a new fungal species and genus in Central Europe that attacks the pollen cones of three spruce species. The new ascomycete forms apothecia on stromatized pollen cones of Norway spruce (Picea abies) and Serbian spruce (Picea omorika) in mountain areas and on West Himalayan spruce (Picea smithiana) planted in urban lowland regions of Switzerland, Germany, and Italy. It was also detected in France, based on metabarcode sequences deposited in the GlobalFungi database. Its sudden appearance and the different origins of the host trees in Europe and Asia leave the origin of the fungus unclear. The new fungus might be a neomycete for Europe. A phylogenetic analysis using SSU, LSU, ITS, RPB2, and TEF1 sequences classified the fungus as a member of Sclerotiniaceae (Helotiales, Leotiomycetes). However, it differs morphologically from the other genera of this family in having an ascus without apical apparatus containing four mainly citriform spores with 16 nuclei each. Furthermore, it is the only known cup fungus that parasitizes pollen cones of conifers by stromatizing their tissue and infecting pollen grains. The fungus does not seem to cause major damage to the spruce populations, as only a few pollen cones per tree are affected. All this leads us to describe the newly discovered fungus as the new species and new genus Microstrobilinia castrans, the fungus that castrates pollen cones of spruce.
APA, Harvard, Vancouver, ISO, and other styles
23

Veloso-Alarcón, Mario E., Peter Urban, Tim Weiss, Kevin Köser, Mengkun She, and Jens Greinert. "Quantitatively Monitoring Bubble-Flow at a Seep Site Offshore Oregon: Field Trials and Methodological Advances for Parallel Optical and Hydroacoustical Measurements." Frontiers in Earth Science 10 (July 22, 2022). http://dx.doi.org/10.3389/feart.2022.858992.

Full text
Abstract:
Two lander-based devices, the Bubble-Box and GasQuant-II, were used to investigate the spatial and temporal variability and total gas flow rates of a seep area offshore Oregon, United States. The Bubble-Box is a stereo camera–equipped lander that records bubbles inside a rising corridor with 80 Hz, allowing for automated image analyses of bubble size distributions and rising speeds. GasQuant is a hydroacoustic lander using a horizontally oriented multibeam swath to record the backscatter intensity of bubble streams passing the swath plain. The experimental set up at the Astoria Canyon site at a water depth of about 500 m aimed at calibrating the hydroacoustic GasQuant data with the visual Bubble-Box data for a spatial and temporal flow rate quantification of the site. For about 90 h in total, both systems were deployed simultaneously and pressure and temperature data were recorded using a CTD as well. Detailed image analyses show a Gaussian-like bubble size distribution of bubbles with a radius of 0.6–6 mm (mean 2.5 mm, std. dev. 0.25 mm); this is very similar to other measurements reported in the literature. Rising speeds ranged from 15 to 37 cm/s between 1- and 5-mm bubble sizes and are thus, in parts, slightly faster than reported elsewhere. Bubble sizes and calculated flow rates are rather constant over time at the two monitored bubble streams. Flow rates of these individual bubble streams are in the range of 544–1,278 mm3/s. One Bubble-Box data set was used to calibrate the acoustic backscatter response of the GasQuant data, enabling us to calculate a flow rate of the ensonified seep area (∼1,700 m2) that ranged from 4.98 to 8.33 L/min (5.38 × 106 to 9.01 × 106 CH4 mol/year). Such flow rates are common for seep areas of similar size, and as such, this location is classified as a normally active seep area. For deriving these acoustically based flow rates, the detailed data pre-processing considered echogram gridding methods of the swath data and bubble responses at the respective water depth. The described method uses the inverse gas flow quantification approach and gives an in-depth example of the benefits of using acoustic and optical methods in tandem.
APA, Harvard, Vancouver, ISO, and other styles
24

Admin, Admin, and Dr Mustafa Arslan. "Effect of dexmedetomidine on ischemia-reperfusion injury of liver and kidney tissues in experimental diabetes and hepatic ischemia-reperfusion injury induced rats." Anaesthesia, Pain & Intensive Care, May 9, 2019, 143–49. http://dx.doi.org/10.35975/apic.v0i0.641.

Full text
Abstract:
Background: Reperfusion following ischemia can lead to more injuries than ischemia itself especially in diabetic patients. The aim of this study was to evaluate the effect of dexmedetomidine on ischemia-reperfusion injury (IRI) in rats with have hepatic IRI and diabetes mellitus. Methodology: Twenty-eight Wistar Albino rats were randomised into four groups as control (C), diabetic (DC), diabetic with hepatic ischemia-reperfusion injury (DIR), and diabetic but administered dexmedetomidine followed by hepatic IRI (DIRD) groups. Hepatic tissue samples were evaluated histopathologically by semiquantitative methods. Malondialdehyde (MDA), superoxide dismutase (SOD), glutathion s-transpherase (GST), and catalase (CAT) enzyme levels were investigated in liver and kidney tissues as oxidative state parameters. Results: In Group DIR; hepatocyte degeneration, sinusoidal dilatation, pycnotic nucleus, and necrotic cells were found to be more in rat hepatic tissue; while mononuclear cell infiltration was higher in the parenchyme. MDA levels were significantly lower; but SOD levels were significantly higher in Group DIRD with regard to Group DIR. In the IRI induced diabetic rats’ hepatic and nephrotic tissues MDA levels, showing oxidative injury, were found to be lower. SOD levels, showing early antioxidant activity, were higher. Conclusion: The enzymatic findings of our study together with the hepatic histopathology indicate that dexmedetomidine has a potential role to decrease IRI. Key words: Hepatic ischemia reperfusion injury; Diabetes mellitus; Dexmedetomidine; Rat; MDA; SOD Citation: Sezen SC, Işık B, Bilge M, Arslan M, Çomu FM, Öztürk L, Kesimci E, Kavutçu M. Effect of dexmedetomidine on ischemia-reperfusion injury of liver and kidney tissues in experimental diabetes and hepatic ischemia-reperfusion injury induced rats. Anaesth Pain & Intensive Care 2016;20(2):143-149 Received: 21 November 2015; Reviewed: 10, 24 December 2015, 9, 10 June 2016; Corrected: 12 December 2015; Accepted: 10 June 2016 INTRODUCTİON Perioperative acute tissue injury induced by ischemia-reperfusion is a comman clinical event caused by reduced blood supply to the tissue being compromised during major surgery. Ischemia leads to cellular injury by depleting cellular energy deposits and resulting in accumulation of toxic metabolites. The reperfusion of tissues that have remained in ischemic conditions causes even more damage.1 Furthermore hepatic ischemia-reperfusion injury (IRI) demonstrates a strong relationship with peri-operative acute kidney injury.2 The etiology of diabetic complications is strongly associated with increased oxidative stress (OS). Diabetic patients are known to have a high risk of developing OS or IRI which results with tissue failure.3 The most important role in ischemia and reperfusion is played by free oxygen radicals.1 In diabetes, characterized by hyperglycemia, even more free oxygen radicals are produced due to oxidation of glucose and glycosylation of proteins.3 The structures which are most sensitive to free oxygen radicals in the cells are membrane lipids, proteins, nucleic acids and deoxyribonucleic acids.1 It has been reported that endogenous antioxidant enzymes [superoxide dismutase (SOD), glutathion s-transpherase (GST), catalase (CAT)] play an important role to alleviate IRI.4-8 Also some pharmacological agents have certain effects on IRI.1 The anesthetic agents influence endogenous antioxidant systems and free oxygen radical formation.9-12 Dexmedetomidine is a selective α-2 adrenoceptor agonist agent. It has been described as a useful and safe adjunct in many clinical applications. It has been found that it may increase urine output by considerably redistributing cardiac output, inhibiting vasopressin secretion and maintaining renal blood flow and glomerular filtration. Previous studies demonstrated that dexmedetomidine provides protection against renal, focal cerebral, cardiac, testicular, and tourniquet-induced IRI.13-18 Arslan et al observed that dexmedetomidine protected against lipid peroxidation and cellular membrane alterations in hepatic IRI, when given before induction of ischemia.17 Si et al18 demonstrated that dexmedetomidine treatment results in a partial but significant attenuation of renal demage induced by IRI through the inactivation of JAK/STAT signaling pathway in an in vivo model. The efficacy of the dexmedetomidine for IRI in diabetic patient is not resarched yet. The purpose of this experimental study was to evaluate the biochemical and histological effects of dexmedetomidine on hepatic IRI in diabetic rat’s hepatic and renal tissue. METHODOLOGY Animals and Experimental Protocol: This study was conducted in the Physiology Laboratory of Kirikkale University upon the consent of the Experimental Animals Ethics Committee of Kirikkale University. All of the procedures were performed according to the accepted standards of the Guide for the Care and Use of Laboratory Animals. In the study, 28 male Wistar Albino rats, weighing between 250 and 300 g, raised under the same environmental conditions, were used. The rats were kept under 20-21 oC at cycles of 12-hour daylight and 12-hour darkness and had free access to food until 2 hours before the anesthesia procedure. The animals were randomly separated into four groups, each containing 7 rats. Diabetes was induced by a single intraperitoneal injection of streptozotocin (Sigma Chemical, St. Louis, MO, USA) at a dose of 65 mg/kg body weight. The blood glucose levels were measured at 72 hrs following this injection. Rats were classified as diabetic if their fasting blood glucose (FBG) levels exceeded 250 mg/dl, and only animals with FBGs of > 250 mg/dl were included in the diabetic groups (dia­betes only, diabetes plus ischemia-reperfusion and diabetes plus dexmedetomidine-ischemia-reperfusion). The rats were kept alive 4 weeks after streptozotocin injection to allow development of chronic dia­betes before they were exposed to ischemia-reperfusion.(19) The rats were weighed before the study. Rats were anesthetized with intraperitoneal ketamine 100 mg/kg. The chest and abdomen were shaved and each animal was fixed in a supine position on the operating table. The abdomen was cleaned with 1% polyvinyl iodine and when dry, the operating field was covered with a sterile drape and median laparotomy was performed. There were four experimental groups (Group C (sham-control; n = 7), (Group DC (diabetes-sham-control; n = 7), Group DIR (diabetes-ischemia-reperfusion; n = 7), and Group DIRD (diabetes-ischemia-reperfusion-dexmedetomidine; n = 7). Sham operation was performed on the rats in Group C and Group DC. The sham operation consisted of mobilization of the hepatic pedicle only. The rats in this group were sacrificed 90 min after the procedure. Hepatic I/R injury was induced in Groups DIR and DIRD respectively with hepatic pedicle clamping using a vascular clamp as in the previous study of Arslan et al.(17) After an ischemic period of 45 min, the vascular clamp was removed. A reperfusion period was maintained for 45 min. In Group DIRD, dexmedetomidine hydrochloride 100 μg/kg, (Precedex 100 μg/2 ml, Abbott®, Abbott Laboratory, North Chicago, Illinois, USA) was administrated via intraperitoneal route 30 minutes before surgery. All the rats were given ketamine 100 mg/kg intraperitoneally and intracardiac blood samples were obtained. Preserving the tissue integrity by avoiding trauma, liver and renal biopsy samples were obtained. Biochemical Analysis: The liver and renal tissues were first washed with cold deionized water to discard blood contamination and then homogenized in a homogenizer. Measurements on cell contest require an initial preparation of the tissues. The preparation procedure may involve grinding of the tissue in a ground glass tissue blender using a rotor driven by a simple electric motor. The homogenizer as a tissue blender similar to the typical kitchen blender is used to emulsify and pulverize the tissue (Heidolph Instruments GMBH & CO KGDiax 900 Germany®) at 1000 U for about 3 min. After centrifugation at 10,000 g for about 60 min, the upper clear layer was taken. MDA levels were determined using the method of Van Ye et al,(20) based on the reaction of MDA with thiobarbituric acid (TBA). In the TBA test reaction, MDA and TBA react in acid pH to form a pink pigment with an absorption maximum at 532 nm. Arbitrary values obtained were compared with a series of standard solutions (1,1,3,3-tetraethoxypropane). Results were expressed as nmol/mg.protein. Part of the homogenate was extracted in ethanol/chloroform mixture (5/3 v/v) to discard the lipid fraction, which caused interferences in the activity measurements of T-SOD, CAT and GST activities. After centrifugation at 10.000 x g for 60 min, the upper clear layer was removed and used for the T-SOD, CAT, GST enzyme activity measurement by methods as described by Durak et al21, Aebi22 and Habig et al23 respectively. One unit of SOD activity was defined as the enzyme protein amount causing 50% inhibition in NBTH2 reduction rate and result were expressed in U/mg protein. The CAT activity method is based on the measurement of absorbance decrease due to H2O2 consumption at 240 nm. The GST activity method is based on the measurement of absorbance changes at 340 nm due to formation of GSH-CDNB complex. Histological determinations: Semiquantitative evaluation technique used by Abdel-Wahhab et al(24) was applied for interpreting the structural changes investigated in hepatic tissues of control and research groups. According to this, (-) (negative point) represents no structural change, while (+) (one positive point) represents mild, (++) (two positive points) medium and (+++) (three positive points) represents severe structural changes. Statistical analysis: The Statistical Package for the Social Sciences (SPSS, Chicago, IL, USA) 20.0 softwre was used for the statistical analysis. Variations in oxidative state parameters, and histopathological examination between study groups were assessed using the Kruskal-Wallis test. The Bonferroni-adjusted Mann-Whitney U-test was used after significant Kruskal-Wallis to determine which groups differed from the others. Results were expressed as mean ± standard deviation (Mean ± SD). Statistical significance was set at a p value < 0.05 for all analyses. RESULTS There was statistically significant difference observed between the groups with respect to findings from the histological changes in the rat liver tissue (hepatocyte degeneration, sinüsoidal dilatation, pycnotic nucleus, prenecrotic cell) determined by light microscopy according to semiquantitative evaluation techniques (p < 0.0001). In Group DIR, hepatocyte degeneration was significantly high compared to Group C, Group DC and Group DIRD (p < 0.0001, p < 0.0001, p = 0.002, respectively), (Table 1, Figure 1-4). Similarly, sinüsoidal dilatation was significantly higher in Group DIR (p < 0.0001, p = 0.004, p = 0.015, respectively). Although, pcynotic nucleus was decreased in Group DIRD, it did not make a significant difference in comparison to Group DIR (p = 0.053), (Table 1, Figure 1-4). The prenecrotic cells were significantly increased in Group DIR, with respect to Group C, Group DC and Group DIRD (p < 0.0001, p = 0.004, p < 0.0001, respectively), (Table 1, Figure 1-4). Table 1. The comparison of histological changes in rat hepatic tissue [Mean ± SD)] p**: Statistical significance was set at a p value < 0.05 for Kruskal-Wallis test *p < 0.05: When compared with Group DIR Figure 1: Light microscopic view of hepatic tissue of Group C (control). VC: vena centralis, *: sinusoids. ®: hepatocytes, k: Kupffer cells, G: glycogen granules, mc: minimal cellular changes, Hematoxilen & Eosin x 40 Figure 2: Light-microscopic view of hepatic tissue of Group DC (diabetes mellitus control) (G: Glycogen granules increased in number, (VC: vena centralis, *:sinusoids. ®:hepatocytes, k:Kupffer cells, G: glycogen granules, mc: minimal cellular changes; Hematoxylin & Eosin x 40) Figure 3: Light-microscopic view of hepatic tissue of Group DIR (Diabetes Mellitus and ischemia-reperfusion) (VC: vena centralis, (H) degenerative and hydrophic hepatocytes, (dej) vena centralis degeneration (centrolobar injury) (*): sinusoid dilatation. (←) pycnotic and hyperchromatic nuclei, MNL: mononuclear cell infiltration, (¯) congestion, K: Kupffer cell hyperplasia, (­) vacuolar degeneration (Hematoxylin & Eosin x 40) Figure 4: Light-microscopic view of hepatic tissue of Group DIRD (Diabetes Mellitus and ischemia-reperfusion together with dexmedetomidine applied group) (VC: vena centralis, (MNL) mononuclear cell infiltration, (dej) hydrophilic degeneration in hepatocytes around vena centralis, (conj) congestion, G: glycogen granules, (←) pycnotic and hyperchromatic nuclei, sinusoid dilatation (*) (Hematoxylin & Eosin x 40) Besides, in liver tissue parenchyma, MN cellular infiltration was a light microscopic finding; and showed significant changes among the groups (p < 0.0001). This was significantly higher in Group DIR, compared to Group C, DC, and DIRD (p < 0.0001, p=0.007, p = 0.007, respectively), (Table 1, Figure 1-4). The enzymatic activity of MDA, SOD and GST in hepatic tissues showed significant differences among the groups [(p = 0.019), (p = 0.034). (p = 0.008) respectively]. MDA enzyme activity was significantly incresed in Group DIR, according to Group C and Group DIRD (p = 0.011, p = 0.016, respectively), (Table 2). In Group DIR SOD enzyme activity was lower with respect to Group C and Group DIRD (p = 0.010, p = 0.038, respectively), (Table 2). The GST enzyme activity was significantly higher in Group DIR, when compared to Group C, DC and DIRD (p = 0.007, p = 0.038, p = 0.039, respectively), (Table 2). Table 2. Oxidative state parameters in rat hepatic tissue [Mean ± SD] p**: Statistical significance was set at a p value < 0.05 for Kruskal-Wallis test *p < 0.05: When compared with Group DIR The enzymatic activity of MDA, SOD in renal tissues, showed significant differences among the groups [(p < 0.0001), (p = 0.008) respectively ]. MDA enzyme activity was significantly incresed in Group DIR, according to Group C and Group DIRD (p < 0.0001, p < 0.0001, respectively). Also MDA enzyme activity level was significantly increased in Group DC, in comparison to Group C and Group DIRD (p = 0.003, p = 0.001, respectively), (Table 3). In Group DIR SOD enzyme activity was lower with respect to Group C and Group DIRD (p = 0.032, p = 0.013, respectively), (Table 3). The GST enzyme activity was significantly higher in Group DIR than the other three groups, however; CAT levels were similar among the groups (Table 3). Table 3: Oxidative state parameters in rat nephrotic tissue [Mean ± SD)] p**: Statistical significance was set at a p value < 0.05 for Kruskal-Wallis test *p < 0.05: When compared with Group DIR DISCUSSION In this study, we have reported the protective effect of dexmedetomidine in experimental hepatic and renal IRI model in the rat by investigating the MDA and SOD levels biochemically. Besides, hepatic histopathological findings also supported our report. Ischemic damage may occur with trauma, hemorrhagic shock, and some surgical interventions, mainly hepatic and renal resections. Reperfusion following ischemia results in even more injury than ischemia itself. IRI is an inflammatory response accompanied by free radical formation, leucocyte migration and activation, sinusoidal endothelial cellular damage, deteoriated microcirculation and coagulation and complement system activation.1 We also detected injury in hepatic and renal tissue caused by reperfusion following ischemia in liver. Experimental and clinical evidence indicates that OS is involved in both the pathogenesis and the complications of diabetes mellitus.25,26 Diabetes mellitus is a serious risk factor for the development of renal and cardiovascular disease. It is also related to fatty changes in the liver.27 Diabetes-related organ damage seems to be the result of multiple mechanisms. Diabetes has been associated with increased free radical reactions and oxidant tissue damage in STZ-induced diabetic rats and also in patients.26Oxidative stress has been implicated in the destruction of pancreatic β-cells28 and could largely contribute to the oxidant tissue damage associated with chronic hyperglycemia.29 A number of reports have shown that antioxidants can attenuate the complications of diabetes in patients30 and in experimental models.28,31 This study demonstrated that diabetes causes a tendency to increase the IRI. There is a lot of investigations related to the pharmacological agents or food supplements applied for decreasing OS and IRI. Antioxidant agents paly an important role in IRI by effecting antioxidant system or lessening the formation of ROS. It has been reported that anesthetic agents too, are effective in oxidative stress.1 During surgical interventions, it seems rational to get benefit from anesthetic agents in prevention of OS caused by IRI instead of using other agents. It has been declared that; dexmedetomidine; as an α-2 agonist with sedative, hypnotic properties; is important in prevention of renal, focal, cerebral, cardiac, testicular and tourniquet-induced IRI.13-18 On the other hand Bostankolu et al. concluded that dexmedetomidine did not have an additional protective role for tournique induced IRI during routine general anesthesia.32 In this study; we have shown that dexmedetomidine has a reducing effect in IRI in diabetic rats. Some biochemical tests and histopathological evaluations are applied for bringing up oxidative stress and IRI in the tissues. Reactive oxygen species (ROS) that appear with reperfusion injury damage cellular structures through the process of the lipid peroxidation of cellular membranes and yield toxic metabolites such as MDA.33 As an important intermidiate product in lipid peroxidation, MDA is used as a sensitive marker of IRI.34 ROS-induced tissue injury is triggered by various defense mechanisms.35 The first defence mechanisms include the antioxidant enzymes of SOD, CAT, and GPx. These endogenous antioxidants are the first lines of defence against oxidative stres and act by scavenging potentially damaging free radical moieties.36 There is a balance between ROS and the scavenging capacity of antioxidant enzymes.1-8 In this study, for evaluation of oxidative damage and antioxidant activity, MDS, SOD, GST and CAT levels were determined in liver and kidney tissues. MDA levels in hepatic and renal tissues were higher in Group DIR compared to Group C and Group DIRD. GST levels were higher in Group DIR compared to all the other three groups. When the groups were arranged from highest to lowest order, with respect to CAT levels, the order was; Group DIR, Group DIRD, Group DC and Group C. However, the difference was not significant. The acute phase reactant MDA, as a marker of OS, was found to be high in Group DIR and low in Group DIRD. This could be interpreted as the presence of protective effect of dexmedetomidine in IRI. IRI developing in splanchnic area causes injury also in the other organs.35 Leithead et al showed that clinically significant hepatic IRI demonstrates a strong relationship with peri-operative acute kidney injury.2 In our experimental research that showed correlation to that of research by Leithead et al. After hepatic IRI in diabetic rats renal OS marker MDA levels were significantly more in Group DIR than Group DIRD. In our study, we observed histopathological changes in the ischemic liver tissue and alterations in the level of MDA, SOD, GST and CAT levels which are OS markers. Histopathological changes of the liver tissues are hepatocyt degeneration, sinusoidal dilatation, nuclear picnosis, celluler necrosis, mononuclear cell infiltrationat paranchimal tissue. These histopathological injury scores were significantly lower in the Group DIRD than those in group DIR. LIMITATION Study limitation is there was no negative control group, as this type of surgical intervention is not possible in rats without anesthesia. CONCLUSION The enzymatic findings of our study together with the hepatic histopathology indicate that dexmedetomidine has a potential role to decrease ischemia-reperfusion injury. Conflict of interest and funding: The authors have not received any funding or benefits from industry or elsewhere to conduct this study. Author contribution: ŞCS: Concept, conduction of the study work and manuscript editing; BI: the main author to write the article; MB & MK: biochemical analysis; MA: manuscript writing; FMÇ: helped us with experimental study; LÖ & EK: collection of data REFERENCES Collard CD, Gelman S. Pathophysiology, clinical manifestations, and prevention of ischemia-reperfusion injury. Anesthesiology. 2001;94(6):1133. [PubMed] [Free full text] Leithead JA, Armstrong MJ, Corbett C, Andrew M, Kothari C, Gunson BK, et al. Hepatic ischemia reperfusion injury is associated with acute kidney injury following donation after brain death liver transplantation. Transpl Int. 2013;26(11):1116. doi: 10.1111/tri.12175. [PubMed] [Free full text] Panés J, Kurose I, Rodriguez-Vaca D, Anderson DC, Miyasaka M, Tso P, et al. Diabetes exacerbates inflammatory responses to ischemia-reperfusion. Circulation. 1996;93(1):161. [PubMed] [Free full text] Touyz RM. Reactive oxygen species and angiotensin II signaling in vascular cells-implications in cardiovascular disease. Braz J Med Biol Res. 2004;37:1263. [PubMed] [Free full text] Olivares-Corichi IM, Ceballos G, Ortega-Camarillo C, Guzman-Grenfell AM, Hicks JJ. Reactive oxygen species (ROS) induce chemical and structural changes on human insulin in vitro, including alterations in its immunoreactivity. Front Biosci. 2005;10:834. [PubMed] Witko-Sarsat V, Friedlander M, Capeillere-Blandin C, Nguyen-Khoa T, Nguyen AT, Zingraff J, et al. Advanced oxidation protein products as a novel marker of oxidative stress in uremia. Kidney Int. 1996;49:1304. [PubMed] Harman D. Free radical theory of aging: An update: Increasing the functional life span. Ann N Y Acad Sci. 2006;1067:10. [PubMed] Nita DA, Nita V, Spulber S, Moldovan M, Popa DP, Zagrean AM, Zagrean L. Oxidative damage following cerebral ischemia depends on reperfusion – a biochemical study in rat. J Cell Mol Med. 2001;5:163–170. [PubMed] [Free full text] Annecke T, Kubitz JC, Kahr S, Hilberath JM, Langer K, Kemming GI, et al. Effects of sevoflurane and propofol on ischaemia-reperfusion injury after thoracic-aortic occlusion in pigs. Br J Anaesth. 2007;98(5):581. [PubMed] [Free full text] De Hert SG, Van der Linden PJ, Cromheecke S, Meeus R, Nelis A, Van Reeth V, ten Broecke PW, et al. Cardioprotective properties of sevoflurane in patients undergoing coronary surgery with cardiopulmonary bypass are related to the modalities of its administration. Anesthesiology. 2004;101(2):299. [PubMed] [Free full text] Yuzer H, Yuzbasioglu MF, Ciralik H, Kurutas EB, Ozkan OV, Bulbuloglu E, et al. Effects of intravenous anesthetics on renal ischemia/reperfusion injury. Ren Fail. 2009;31(4):290. [PubMed] [Free full text] Lee HT, Ota-Setlik A, Fu Y, Nasr SH, Emala CW. Differential protective effects of volatile anesthetics against renal ischemia-reperfusion injury in vivo. Anesthesiology. 2004;101(6):1313. [PubMed] [Free full text] Lai YC, Tsai PS, Huang CJ. Effects of dexmedetomidine on regulating endotoxin-induced up-regulation of inflammatory molecules in murine macrophages. J Surg Res. 2009;154(2):212. doi: 10.1016/j.jss.2008.07.010. [PubMed] Yoshitomi O, Cho S, Hara T, Shibata I, Maekawa T, Ureshino H, Sumikawa K. Direct protective effects of dexmedetomidine against myocardial ischemia-reperfusion injury in anesthetized pigs. Shock. 2012;38(1):92. doi: 10.1097/SHK.0b013e318254d3fb. [PubMed] Jolkkonen J, Puurunen K, Koistinaho J, Kauppinen R, Haapalinna A, Nieminen L, et al. Neuroprotection by the alpha2-adrenoceptor agonist, dexmedetomidine, in rat focal cerebral ischemia. Eur J Pharmacol. 1999;372(1):31. [PubMed] Kocoglu H, Ozturk H, Ozturk H, Yilmaz F, Gulcu N. Effect of dexmedetomidine on ischemia-reperfusion injury in rat kidney: a histopathologic study. Ren Fail. 2009;31(1):70. doi: 10.1080/08860220802546487. [PubMed] Arslan M, Çomu FM, Küçük A, Öztürk L, Yaylak F. Dexmedetomidine protects against lipid peroxidation and erythrocyte deformability alterations in experimental hepatic ischemia reperfusion injury. Libyan J Med. 2012;7. doi: 10.3402/ljm.v7i0.18185 [PubMed] [Free full text] Si Y, Bao H, Han L, Shi H, Zhang Y, Xu L, et al. Dexmedetomidine protects against renal ischemia and reperfusion injury by inhibiting the JAK/STAT signaling activation. J Transl Med. 2013;11(1):141. doi: 10.1186/1479-5876-11-141. [PubMed][Free full text] Türeci E, İş M, Üzüm G, Akyüz F, Ulu MO, Döşoğlu M, et al. Alterations in blood-brain barrier after traumatic brain injury in streptozotocin-induced diabetic rats. J Nervous Sys Surgery 2009;2(2):79. [Free full text] Van Ye TM, Roza AM, Pieper GM, Henderson J Jr, Johnson JP, Adams MB. Inhibition of intestinal lipid peroxidation does not minimize morphological damage. J Surg Res 1993;55:553. [PubMed] Durak I, Canbolat O, Kavutcu M, Öztürk HS, Yurtarslanı Z. Activities of total, cytoplasmic and mihochondrial superoxide dismutase enzymes in sera and pleural fluids from patient with lung cancer. J Clin Lab Anal 1996;10:17. [PubMed] Aebi H. Catalase. In: H.U.Bergmeyer (Ed): Methods of Enzymatic Analysis, Academic Press , New York and London, 1974;pp.673-677. Habig WH, Pabst MJ, Jakoby WB. Glutathione S-transferases. The first enzymatic step in mercapturic acid formation. J Biol Chem 1974;249:7130. [PubMed] [Free full text] Abdel-Wahhab MA, Nada SA, Arbid MS. Ochratoxicosis: Prevention of developmental toxicity by L-methionine in rats. J Appl Toxicol 1999;19:7. [PubMed] Wolff SP. Diabetes mellitus and free radicals: free radicals, transition metals and oxidative stress in the aetiology of diabetes mellitus and complications. Br Med Bull. 1993;49:642. [PubMed] [Free full text] West IC. Radicals and oxidative stress in diabetes. Diabet Med. 2000;17:171–180. [PubMed] Wanless IR, Lentz JS. Fatty liver hepatitis (steatohepatitis) and obesity: an autopsy study with analysis risk factors. Hepatology. 1990;12:1106. [PubMed] Hotta M, Tashiro F, Ikegami H, Niwa H, Ogihara T, Yodoi J, Miyazaki J. Pancreatic cell-specific expression of thioredoxin, an antioxidative and antiapoptotic protein, prevents autoimmune and streptozotocin-induced diabetes. J Exp Med. 1998;188:1445. [PubMed] [Free full text] Baynes JW. Role of oxidative stress in the development of complications in diabetes. Diabetes. 1991;40:405. [PubMed] Borcea V, Nourooz-Zadeh J, Wolff SP, Klevesath M, Hofmann M, Urich H, et al. α-Lipoic acid decreases oxidative stress even in diabetic patients with poor glycemic control and albuminuria. Free Radic Biol Med. 1999;26:1495. [PubMed] Fitzl G, Martin R, Dettmer D, Hermsdorf V, Drews H, Welt K. Protective effect of ginkgo biloba extract EGb 761 on myocardium of experimentally diabetic rats, I: ultrastructural and biochemical investigation on cardiomyocytes. Exp Toxicol Pathol. 1999;51:189. [PubMed] Bostankolu E, Ayoglu H, Yurtlu S, Okyay RD, Erdogan G, Deniz Y, et al. Dexmedetomidine did not reduce the effects of tourniquet-induced ischemia-reperfusion injury during general anesthesia. Kaohsiung J Med Sci. 2013;29(2):75. doi: 10.1016/j.kjms.2012.08.013. [PubMed] [Free full text] Wakai A, Wang JH, Winter DC, Street JT, O’Sullivan RG, Redmond HP. Tourniquet-induced systemic inflammatory response in extremity surgery. J Trauma 2001;51:922. [PubMed] Concannon MJ, Kester CG, Welsh CF, Puckett CL. Patterns of free-radical production after tourniquet ischemia implications for the hand surgeon. Plast Reconstr Surg 1992;89:846. [PubMed] Grisham MB, Granger DN. Free radicals: reactive metabolites of oxygen as mediators of postischemic reperfusion injury. In: Martson A, Bulkley GB, Fiddian-Green RG, Haglund U, editors. Splanchnic İschemia and Multiple Organ Failure. St Louis, MO: Mosby;1989. pp. 135–144. Mccard JM. The evolution of free radicals and oxidative stress. Am J Med 2000;108:652. [PubMed]
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography