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1
Eys, S., D. Schwartz, W. Wohlleben, and E. Schinko. "Three Thioesterases Are Involved in the Biosynthesis of Phosphinothricin Tripeptide in Streptomyces viridochromogenes Tü494." Antimicrobial Agents and Chemotherapy 52, no. 5 (February 19, 2008): 1686–96. http://dx.doi.org/10.1128/aac.01053-07.
Повний текст джерелаАнотація:
ABSTRACT Phosphinothricin tripeptide (PTT) is a peptide antibiotic produced by Streptomyces viridochromogenes Tü494, and it is synthesized by nonribosomal peptide synthetases. The PTT biosynthetic gene cluster contains three peptide synthetase genes: phsA, phsB, and phsC. Each of these peptide synthetases comprises only one module. In neither PhsB nor PhsC is a typical C-terminal thioesterase domain present. In contrast, a single thioesterase GXSXG motif has been identified in the N terminus of the first peptide synthetase, PhsA. In addition, two external thioesterase genes, theA and theB, are located within the PTT biosynthetic gene cluster. To analyze the thioesterase function as well as the assembly of the peptide synthetases within PTT biosynthesis, several mutants were generated and analyzed. A phsA deletion mutant (MphsA) was complemented with two different phsA constructs that were carrying mutations in the thioesterase motif. In one construct, the thioesterase motif comprising 45 amino acids of phsA were deleted. In the second construct, the conserved serine residue of the GXSXG motif was replaced by an alanine. In both cases, the complementation of MphsA did not restore PTT biosynthesis, revealing that the thioesterase motif in the N terminus of PhsA is required for PTT production. In contrast, TheA and TheB might have editing functions, as an interruption of the theA and theB genes led to reduced PTT production, whereas an overexpression of both genes in the wild type enhanced the PTT yield. The presence of an active single thioesterase motif in the N terminus of PhsA points to a novel mechanism of product release.
2
Schwartz, Dirk, Nicolas Grammel, Eva Heinzelmann, Ullrich Keller, and Wolfgang Wohlleben. "Phosphinothricin Tripeptide Synthetases in Streptomyces viridochromogenes Tü494." Antimicrobial Agents and Chemotherapy 49, no. 11 (November 2005): 4598–607. http://dx.doi.org/10.1128/aac.49.11.4598-4607.2005.
Повний текст джерелаАнотація:
ABSTRACT The tripeptide backbone of phosphinothricin (PT) tripeptide (PTT), a compound with herbicidal activity from Streptomyces viridochromogenes, is assembled by three stand-alone peptide synthetase modules. The enzyme PhsA (66 kDa) recruits the PT-precursor N-acetyl-demethylphosphinothricin (N-Ac-DMPT), whereas the two alanine residues of PTT are assembled by the enzymes PhsB and PhsC (129 and 119 kDa, respectively). During or after assembly, the N-Ac-DMPT residue in the peptide is converted to PT by methylation and deacetylation. Both phsB and phsC appear to be cotranscribed together with two other genes from a single promoter and they are located at a distance of 20 kb from the gene phsA, encoding PhsA, in the PTT biosynthesis gene cluster of S. viridochromogenes. PhsB and PhsC represent single nonribosomal peptide synthetase elongation modules lacking a thioesterase domain. Gene inactivations, genetic complementations, determinations of substrate specificity of the heterologously produced proteins, and comparison of PhsC sequence with the amino terminus of the alanine-activating nonribosomal peptide synthetase PTTSII from S. viridochromogenes confirmed the role of the two genes in the bialanylation of Ac-DMPT. The lack of an integral thioesterase domain in the PTT assembly system points to product release possibly involving two type II thioesterase genes (the1 and the2) located in the PTT gene cluster alone or in conjunction with an as yet unknown mechanism of product release.
3
Teimoori, Shahnaz, Amir Hessam Hassani *©, and Mostafaa Panaahie. "the Extraction and determination of benzene from waters and wastewater samples based on functionalized carbon nanotubes by static head space gas chromatography mass spectrometry." Analytical Methods in Environmental Chemistry Journal 3, no. 01 (March 26, 2020): 17–26. http://dx.doi.org/10.24200/amecj.v3.i01.91.
Повний текст джерелаАнотація:
In this study, the phenyl sulfonic acid (PhSA) modified carbon nanotubes (CNTs) were used for benzene removal from waters by (D- μSPE). Due to adsorption mechanism, π–π interactions was provided between the aromatic ring of benzene with the surface (SO3H) and phenyl ring (-C6H5) of CNTs, respectively. Therefore, 20-100 mg of sorbent, concentration of benzene (0.1–10 mg L-1), pH (1-12) and contact time (5–120 min) were investigated and optimized for benzene removal from water samples in static system. The concentration of benzene in water was determined by (SHS-GC-MS). The results showed, the Langmuir-Freundlich (LF) isotherm provided the best fit for benzene sorption. By using the Langmuir model, the maximum adsorption capacity of 117.34 and 22.86 mg/g was achieved for benzene removal from waters with CNTs@PhSA and CNTs, respectively. Under optimal conditions, adsorption efficiency of CNTs@PhSA and CNTs was obtained 97.7% and 20.6 % for benzene removal from water samples, respectively.
4
Calegaro, Vítor Crestani, Cleonice Zatti, Andre Goettems Bastos, and Lucia Helena Machado Freitas. "Suicidal patients in a psychiatric emergency unit: clinical characteristics and aggression profile." Trends in Psychiatry and Psychotherapy 41, no. 1 (March 2019): 9–17. http://dx.doi.org/10.1590/2237-6089-2017-0149.
Повний текст джерелаАнотація:
Abstract Objective To explore and describe a profile of patients admitted to a psychiatric emergency facility, comparing patients with and without a recent suicide attempt in terms of their clinical characteristics and aggression. Methods This was an exploratory comparative study where patients were assessed using the Brief Psychiatric Rating Scale (BPRS) and the Overt Aggression Scale (OAS). Participants with a suicide attempt in the last 24 hours (SA) were compared to participants with a prior history of suicide attempt but no recent attempt (PHSA). Results 63 individuals (SA: 26; PHSA: 37) were selected. Both groups had similar demographic and clinical characteristics. The most prevalent diagnoses were mood (57.1%) and personality (50.8%) disorders. The majority of patients in both groups had a history of aggression episodes. Physical aggression in the week prior to admission was more prevalent in the PHSA group (51.4 vs. 19.2%, p = 0.017). The PHSA group also presented higher activation scores (p = 0.025), while the SA group presented higher affect scores on BPRS dimensions (p = 0.002). Conclusion The majority of individuals with a history of suicide attempt also presented a history of aggression. Inpatients with recent suicide attempt were hospitalized mainly due to the risk of suicide, while those with no recent suicide attempt were hospitalized mainly due to the risk of hetero-aggression. These findings support the hypothesis of an aggressive profile in suicidal patients and may open up a path for future research.
5
Sansonno, Domenico E., Paolo Detomaso, Giuseppe Leone, Gaetano Bufano, Rocco Rizzi, and Onofrio G. Manghisi. "Antibodies to glutaraldehyde-polymerized human albumin (anti-pHSA) in viral hepatitis." Digestive Diseases and Sciences 34, no. 9 (September 1989): 1443–48. http://dx.doi.org/10.1007/bf01538083.
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6
Hutchinson, Ryan C., Kevin J. Wu, John C. Cheville, and David D. Thiel. "Prostatic Stromal Hyperplasia with Atypia." Case Reports in Urology 2013 (2013): 1–2. http://dx.doi.org/10.1155/2013/364124.
Повний текст джерелаАнотація:
Prostatic stromal hyperplasia with atypia (PSHA) is a rare histologic finding diagnosed incidentally on prostate biopsies, transurethral resection specimens, and radical prostatectomy specimens. PSHA has a bizarre histologic appearance and these lesions often raise concern for sarcoma; however, their clinical course is indolent and does not include extraprostatic progression. We discuss a case of PHSA discovered on prostate biopsy performed for an abnormal digital rectal examination and review the literature on this rare pathologic finding.
7
Giacomelli, Fernando Carlos, Fabiano Vargas Pereira, Abdellatif Moussaid, and Nádya Pesce da Silveira. "Dynamic behavior of PMMA-PHSA hard spheres suspensions under external electric field." Macromolecular Symposia 245-246, no. 1 (December 2006): 457–62. http://dx.doi.org/10.1002/masy.200651365.
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8
Hsieh, C. J., and G. H. Jones. "Nucleotide sequence, transcriptional analysis, and glucose regulation of the phenoxazinone synthase gene (phsA) from Streptomyces antibioticus." Journal of bacteriology 177, no. 20 (1995): 5740–47. http://dx.doi.org/10.1128/jb.177.20.5740-5747.1995.
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Chavan, Sayali Ramdas, Patrick Perré, Victor Pozzobon, and Julien Lemaire. "CO2 Absorption Using Hollow Fiber Membrane Contactors: Introducing pH Swing Absorption (pHSA) to Overcome Purity Limitation." Membranes 11, no. 7 (June 30, 2021): 496. http://dx.doi.org/10.3390/membranes11070496.
Повний текст джерелаАнотація:
Recently, membrane contactors have gained more popularity in the field of CO2 removal; however, achieving high purity and competitive recovery for poor soluble gas (H2, N2, or CH4) remains elusive. Hence, a novel process for CO2 removal from a mixture of gases using hollow fiber membrane contactors is investigated theoretically and experimentally. A theoretical model is constructed to show that the dissolved residual CO2 hinders the capacity of the absorbent when it is regenerated. This model, backed up by experimental investigation, proves that achieving a purity > 99% without consuming excessive chemicals or energy remains challenging in a closed-loop system. As a solution, a novel strategy is proposed: the pH Swing Absorption which consists of manipulating the acido–basic equilibrium of CO2 in the absorption and desorption stages by injecting moderate acid and base amount. It aims at decreasing CO2 residual content in the regenerated absorbent, by converting CO2 into its ionic counterparts (HCO3− or CO32−) before absorption and improving CO2 degassing before desorption. Therefore, this strategy unlocks the theoretical limitation due to equilibrium with CO2 residual content in the absorbent and increases considerably the maximum achievable purity. Results also show the dependency of the performance on operating conditions such as total gas pressure and liquid flowrate. For N2/CO2 mixture, this process achieved a nitrogen purity of 99.97% with a N2 recovery rate of 94.13%. Similarly, for H2/CO2 mixture, a maximum H2 purity of 99.96% and recovery rate of 93.96% was obtained using this process. Moreover, the proposed patented process could potentially reduce energy or chemicals consumption.
10
Wei, Wei, Su-fei Wang, Bing Yu, and Ming Ni. "Inhibition of HBV replication by delivering the dual-gene expression vector pHsa-miR16-siRNA in HepG2.2.15 cells." Current Medical Science 37, no. 6 (December 2017): 828–32. http://dx.doi.org/10.1007/s11596-017-1810-0.
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11
Xu, Xiaogang, Shi Wu, Xinyu Ye, Yang Liu, Wanliang Shi, Yingyuan Zhang, and Minggui Wang. "Prevalence and Expression of the Plasmid-Mediated Quinolone Resistance Determinant qnrA1." Antimicrobial Agents and Chemotherapy 51, no. 11 (August 27, 2007): 4105–10. http://dx.doi.org/10.1128/aac.00616-07.
Повний текст джерелаАнотація:
ABSTRACT Since its discovery, qnrA has been found in most common Enterobacteriaceae. Ciprofloxacin MICs conferred by different qnrA-positive plasmids could range from 0.1 μg/ml to 2 μg/ml in Escherichia coli J53. The reasons for different ciprofloxacin MICs conferred by qnrA have not been fully clarified. Five hundred forty-one consecutive gram-negative clinical strains that were resistant or intermediate to ciprofloxacin and that were isolated in Shanghai in 2005 were screened for qnrA by PCR. For qnrA-positive isolates, the transferability of quinolone resistance was determined by conjugation and mutations within the quinolone resistance-determining region (QRDR) of gyrA and parC. aac(6′)-Ib-cr was detected and qnrA RNA expression was determined using real-time reverse transcription-PCR for transconjugants with different ciprofloxacin MICs. The qnrA gene was detected in 7 of the 541 clinical isolates. Quinolone resistance was transferred in four strains by conjugation. Mutations in the QRDR of gyrA and parC were detected in five qnrA-positive clinical strains with higher ciprofloxacin MICs. Of four qnrA-bearing plasmids in E. coli J53, pHS4 and pHS5 conferred ciprofloxacin MICs of 0.094 to 0.125 μg/ml; pHS3, which harbored the aac(6′)-Ib-cr gene as well, conferred a ciprofloxacin MIC of 0.25 μg/ml, and pHS6, which had both the aac(6′)-Ib-cr gene and a high expression level of qnrA, had a ciprofloxacin MIC of 1.0 μg/ml. The prevalence of qnrA appeared to be higher in Enterobacter cloacae than in other Enterobacteriaceae. The coexistence of qnrA and aac(6′)-Ib-cr in a single plasmid and increased qnrA expression can account for the different levels of ciprofloxacin resistance seen in transconjugants.
12
Fargnoli, Mario, and Mara Lombardi. "Preliminary Human Safety Assessment (PHSA) for the Improvement of the Behavioral Aspects of Safety Climate in the Construction Industry." Buildings 9, no. 3 (March 18, 2019): 69. http://dx.doi.org/10.3390/buildings9030069.
Повний текст джерелаАнотація:
Occupational safety in the construction industry still represents a relevant problem at a global level. In fact, the complexity of working activities in this sector requires a comprehensive approach that goes beyond normative compliance to guarantee safer working conditions. In particular, empirical research on the factors influencing the unsafe behavior of workers needs to be augmented. Thus, the relationship between human factors and safety management issues following a bottom-up approach was investigated. In particular, an easy-to-use procedure that can be used to better address workers’ safety needs augmenting the company’s safety climate and supporting safety management issues was developed. Such an approach, based on the assessment of human reliability factors, was verified in a real case study concerning the users of concrete mixer trucks. The results showed that the majority of human failures were action and retrieval errors, underlining the importance of theoretical and practical training programs as a means to improve safety behavior. In such a context, information and communication activities also resulted beneficially to augment the company’s safety climate. The proposed approach, despite its qualitative nature, allows a clearer understanding of workers’ perceptions of hazards and their risk-taking behavior, providing practical cues to monitor and improve the behavioral aspects of safety climate. Hence, these first results can contribute to augmenting safety knowledge in the construction industry, providing a basis for further investigations on the causalities related to human performances, which are considered a key element in the prevention of accidents.
13
Giacomelli, Fernando C., Nádya P. da Silveira, and Petr Štěpánek. "Dynamics of PMMA−PHSA Hard Spheres under External Electric Field at Low Temperatures: a Singular Dynamic Light Scattering Experiment." Macromolecules 42, no. 11 (June 9, 2009): 3818–22. http://dx.doi.org/10.1021/ma900423y.
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14
Schwartz, D., R. Alijah, B. Nussbaumer, S. Pelzer, and W. Wohlleben. "The peptide synthetase gene phsA from Streptomyces viridochromogenes is not juxtaposed with other genes involved in nonribosomal biosynthesis of peptides." Applied and environmental microbiology 62, no. 2 (1996): 570–77. http://dx.doi.org/10.1128/aem.62.2.570-577.1996.
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15
Palangetic, Ljiljana, Kirill Feldman, Raphael Schaller, Romana Kalt, Walter R. Caseri, and Jan Vermant. "From near hard spheres to colloidal surfboards." Faraday Discussions 191 (2016): 325–49. http://dx.doi.org/10.1039/c6fd00052e.
Повний текст джерелаАнотація:
This work revisits the synthesis of the colloidal particles most commonly used for making model near hard suspensions or as building blocks of model colloidal gels, i.e. sterically stabilised poly(methyl methacrylate) (PMMA) particles. The synthesis of these particles is notoriously hard to control and generally the problems are ascribed to the difficulty in synthesising the graft stabiliser (PMMA-g-PHSA). In the present work, it is shown that for improving the reliability of the synthesis as a whole, control over the polycondensation of the 12-polyhydroxystearic acid is the key. By changing the catalyst and performing the polycondensation in the melt, the chain length of the 12-polyhydroxystearic acid is better controlled, as confirmed by 1H-NMR spectroscopy. Control over the graft copolymer now enables us to make small variations of near hard sphere colloids, for example spherical PMMA particles with essentially the same core size and different stabilising layer thicknesses can now be readily produced, imparting controlled particle softness. The PMMA spheres can be further employed to create, in gram scale quantities, colloidal building blocks having geometrical and/or chemical anisotropy by using a range of mechanical deformation methods. The versatility of the latter methods is demonstrated for polystyrene latex particles as well.
16
Mourão, Joana, Andreia Rebelo, Sofia Ribeiro, Luísa Peixe, Carla Novais, and Patrícia Antunes. "Atypical Non-H2S-Producing Monophasic Salmonella Typhimurium ST3478 Strains from Chicken Meat at Processing Stage Are Adapted to Diverse Stresses." Pathogens 9, no. 9 (August 26, 2020): 701. http://dx.doi.org/10.3390/pathogens9090701.
Повний текст джерелаАнотація:
Poultry products are still an important cause of Salmonella infections worldwide, with an increasingly reported expansion of less-frequent serotypes or atypical strains that are frequently multidrug-resistant. Nevertheless, the ability of Salmonella to survive antimicrobials promoted in the context of antibiotic reducing/replacing and farming rethinking (e.g., organic acids and copper in feed/biocides) has been scarcely explored. We investigated Salmonella occurrence (conventional and molecular assays) among chicken meat at the processing stage (n = 53 batches/29 farms) and characterized their tolerance to diverse stress factors (antibiotics, copper, acid pH, and peracetic acid). Whole-genome sequencing was used to assess adaptive features and to perform comparative analysis. We found a low Salmonella occurrence (4%) and identified S. Enteritidis/ST11 plus atypical non-H2S-producing S. 1,4,[5],12:i:-/ST3478. The ST3478 presented the ability to grow under diverse stresses (antibiotics, copper, and acid-pH). Comparative genomics among ST3478 isolates showed similar antibiotic/metal resistance gene repertoires and identical nonsense phsA thiosulfate reductase mutations (related to H2S-negative phenotype), besides their close phylogenetic relationship by cgMLST and SNPs. This study alerts for the ongoing national and international spread of an emerging monophasic Salmonella Typhimurium clonal lineage with an enlarged ability to survive to antimicrobials/biocides commonly used in poultry production, being unnoticed by conventional Salmonella detection approaches due to an atypical non-H2S-producing phenotype.
17
Jones, George H. "Actinomycin Production Persists in a Strain ofStreptomyces antibioticus Lacking Phenoxazinone Synthase." Antimicrobial Agents and Chemotherapy 44, no. 5 (May 1, 2000): 1322–27. http://dx.doi.org/10.1128/aac.44.5.1322-1327.2000.
Повний текст джерелаАнотація:
ABSTRACT Truncated fragments of the phenoxazinone synthase gene,phsA, were prepared by the PCR. The resulting fragments were cloned into conjugative plasmid pKC1132 and transferred toStreptomyces antibioticus by conjugation fromEscherichia coli. Two of the resulting constructs were integrated into the S. antibioticus chromosome by homologous recombination, and each of the resulting strains, designated 3720/pJSE173 and 3720/pJSE174, contained a disrupted phsAgene. Strain 3720/pJSE173 grew poorly, and Southern blotting suggested that genetic changes other than the disruption of the phsAgene might have occurred during the construction of that strain. Strain 3720/pJSE174 sporulated well and grew normally on the medium used to prepare inocula for antibiotic production. Strain 3720/pJSE174 also grew as well as the wild-type strain on antibiotic production medium containing either 1 or 5.7 mM phosphate. Strain 3720/pJSE174 was shown to be devoid of phenoxazinone synthase (PHS) activity, and PHS protein was undetectable in this strain by Western blotting. Despite the absence of detectable PHS activity, strain 3720/pJSE174 produced slightly more actinomycin than did the wild-type parent strain in medium containing 1 or 5.7 mM phosphate. The observation that strain 3720/pJSE174, lacking detectable PHS protein or enzyme activity, retained the ability to produce actinomycin supports the conclusion that PHS is not required for actinomycin biosynthesis in S. antibioticus.
18
Burns, Justin L., and Thomas J. DiChristina. "Anaerobic Respiration of Elemental Sulfur and Thiosulfate by Shewanella oneidensis MR-1 Requires psrA, a Homolog of the phsA Gene of Salmonella enterica Serovar Typhimurium LT2." Applied and Environmental Microbiology 75, no. 16 (June 19, 2009): 5209–17. http://dx.doi.org/10.1128/aem.00888-09.
Повний текст джерелаАнотація:
ABSTRACT Shewanella oneidensis MR-1, a facultatively anaerobic gammaproteobacterium, respires a variety of anaerobic terminal electron acceptors, including the inorganic sulfur compounds sulfite (SO3 2−), thiosulfate (S2O3 2−), tetrathionate (S4O6 2−), and elemental sulfur (S0). The molecular mechanism of anaerobic respiration of inorganic sulfur compounds by S. oneidensis, however, is poorly understood. In the present study, we identified a three-gene cluster in the S. oneidensis genome whose translated products displayed 59 to 73% amino acid similarity to the products of phsABC, a gene cluster required for S0 and S2O3 2− respiration by Salmonella enterica serovar Typhimurium LT2. Homologs of phsA (annotated as psrA) were identified in the genomes of Shewanella strains that reduce S0 and S2O3 2− yet were missing from the genomes of Shewanella strains unable to reduce these electron acceptors. A new suicide vector was constructed and used to generate a markerless, in-frame deletion of psrA, the gene encoding the putative thiosulfate reductase. The psrA deletion mutant (PSRA1) retained expression of downstream genes psrB and psrC but was unable to respire S0 or S2O3 2− as the terminal electron acceptor. Based on these results, we postulate that PsrA functions as the main subunit of the S. oneidensis S2O3 2− terminal reductase whose end products (sulfide [HS−] or SO3 2−) participate in an intraspecies sulfur cycle that drives S0 respiration.
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Biskup, Ewelina, and Xiao-Yu Yang. "Pyogenic Hepatic Abscess – Less is More A Review for General Internists." Praxis 104, no. 20 (January 2015): 1091–95. http://dx.doi.org/10.1024/1661-8157/a002155.
Повний текст джерелаАнотація:
Eitrige Leberabszesse – weniger ist mehr: Review für Internisten Zusammenfassung. Eitrige Leberabszesse (PHAa) sind selten, aber fatal, wenn unbehandelt. Fortschritte in der diagnostischen und interventionellen Radiologie haben das Management der PHAs erleichtert. Dennoch sind Abszesse im Lobus caudatus eine Herausforderung, vor allem für die allgemeine Internisten, die zum Übertherapieren neigen. Literatur über diese spezifische Form der Leberabszesse ist insuffizient. Der Zweck dieses Artikels ist es, einen Überblick über die vorhandene Datenlage zu PHAs im Allgemeinen und insbesondere im Lobus caudatus zu verschaffen, sowie die Aufmerksamkeit der allgemeinen Internisten auf diese wichtige Differenzialdiagnose zu richten und die Therapiewahl zu erleichtern. Wir betonen, dass eine Position im Sinne des «Weniger ist mehr»-Konzeptes für die Qualität der PHA-Therapie empfehlenswert ist.
20
Alvarez-Santullano, Natalia, Pamela Villegas, Mario Sepúlveda Mardones, Roberto E. Durán, Raúl Donoso, Angela González, Claudia Sanhueza, et al. "Genome-Wide Metabolic Reconstruction of the Synthesis of Polyhydroxyalkanoates from Sugars and Fatty Acids by Burkholderia Sensu Lato Species." Microorganisms 9, no. 6 (June 12, 2021): 1290. http://dx.doi.org/10.3390/microorganisms9061290.
Повний текст джерелаАнотація:
Burkholderia sensu lato (s.l.) species have a versatile metabolism. The aims of this review are the genomic reconstruction of the metabolic pathways involved in the synthesis of polyhydroxyalkanoates (PHAs) by Burkholderia s.l. genera, and the characterization of the PHA synthases and the pha genes organization. The reports of the PHA synthesis from different substrates by Burkholderia s.l. strains were reviewed. Genome-guided metabolic reconstruction involving the conversion of sugars and fatty acids into PHAs by 37 Burkholderia s.l. species was performed. Sugars are metabolized via the Entner–Doudoroff (ED), pentose-phosphate (PP), and lower Embden–Meyerhoff–Parnas (EMP) pathways, which produce reducing power through NAD(P)H synthesis and PHA precursors. Fatty acid substrates are metabolized via β-oxidation and de novo synthesis of fatty acids into PHAs. The analysis of 194 Burkholderia s.l. genomes revealed that all strains have the phaC, phaA, and phaB genes for PHA synthesis, wherein the phaC gene is generally present in ≥2 copies. PHA synthases were classified into four phylogenetic groups belonging to class I II and III PHA synthases and one outlier group. The reconstruction of PHAs synthesis revealed a high level of gene redundancy probably reflecting complex regulatory layers that provide fine tuning according to diverse substrates and physiological conditions.
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Nguyen, Phu An, Dr Shouvik Sanyal, Hat Dang Nguyen, Dr Chapala Bohidar, Augustine Okeke, and Chutimon Narawish. "The Effectiveness of Measuring in Supply Chain Operations of E-Marketers." Webology 19, no. 1 (January 20, 2022): 2245–64. http://dx.doi.org/10.14704/web/v19i1/web19153.
Повний текст джерелаАнотація:
Supply Chain Management (SCM) for automotive manufacturers worldwide is one of the most relevant and dynamic problems. This research aims to analyze factors affecting the strategic efficiency of the supply chain (SPSC) and the OPSC by quantitative and quality research in the automotive industries. The research aims to evaluate the main outcomes, such as checked theories and established levels of buildings between IKCO and Isuzu, as studies in the automotive industry. In total, IKCO and Isuzu businesses received a total of 217 and 201 completed questionnaires. SPSS analyzes Cronbach's Alpha, where all values of Alpha are highly reasonable, also tested the reliability of results. Path analyzes (PA) were engaged in discovering the occasional relationship between variables through multi-regression in PHSA, according to SPSC and OPSC as the key-dependent variables. SPSC and OPSC have been structured, based on the PA methodology, to assess IKCO and Isuzu's distribution chain efficiency. The Maximal Factor Likelihood (ML), used for the study of normality, outliers and composite stability, validity, and evaluating theories of Amos, was the foundation for confirmatory factor analyses (CFA). The qualitative analysis was also conducted to clarify the dimensions and assess the actual condition through interviews and documents. In conclusion, study results show that IT, organizational learning (OL), and product creativity (PRI) have affected the strategic success of the supply chain. However, SPSC has little impact on transformational leadership. In addition, method innovation (PI) and relationship efficiency affected the organizational output of the supply chain (PQ). The SPSC and OPSC have first been studied in the automobile sector. The research difference has been established, and the research center and SCM as the key foundation for automotive producers have been recognized.
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Slater, Steven, Kathryn L. Houmiel, Minhtien Tran, Timothy A. Mitsky, Nancy B. Taylor, Stephen R. Padgette та Kenneth J. Gruys. "Multiple β-Ketothiolases Mediate Poly(β-Hydroxyalkanoate) Copolymer Synthesis in Ralstonia eutropha". Journal of Bacteriology 180, № 8 (15 квітня 1998): 1979–87. http://dx.doi.org/10.1128/jb.180.8.1979-1987.1998.
Повний текст джерелаАнотація:
ABSTRACT Polyhydroxyalkanoates (PHAs) are a class of carbon and energy storage polymers produced by numerous bacteria in response to environmental limitation. The type of polymer produced depends on the carbon sources available, the flexibility of the organism’s intermediary metabolism, and the substrate specificity of the PHA biosynthetic enzymes. Ralstonia eutropha produces both the homopolymer poly-β-hydroxybutyrate (PHB) and, when provided with the appropriate substrate, the copolymer poly(β-hydroxybutyrate-co-β-hydroxyvalerate) (PHBV). A required step in production of the hydroxyvalerate moiety of PHBV is the condensation of acetyl coenzyme A (acetyl-CoA) and propionyl-CoA to form β-ketovaleryl-CoA. This activity has generally been attributed to the β-ketothiolase encoded by R. eutropha phbA. However, we have determined that PhbA does not significantly contribute to catalyzing this condensation reaction. Here we report the cloning and genetic analysis of bktB, which encodes a β-ketothiolase from R. eutropha that is capable of forming β-ketovaleryl-CoA. Genetic analyses determined that BktB is the primary condensation enzyme leading to production of β-hydroxyvalerate derived from propionyl-CoA. We also report an additional β-ketothiolase, designated BktC, that probably serves as a secondary route toward β-hydroxyvalerate production.
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Al-Busaidi, A., P. Cookson, and T. Yamamoto. "Methods of pH determination in calcareous soils: use of electrolytes and suspension effect." Soil Research 43, no. 4 (2005): 541. http://dx.doi.org/10.1071/sr04102.
Повний текст джерелаАнотація:
Determination of pH assists in understanding many reactions that occur in soil. However, measured values of soil pH can be affected by the procedure used for determination and by a range of soil properties. In this study, pH was measured in different electrolytes [distilled water (pHw), 0.01 m CaCl2 (pHca), 1 m KCl (pHk), and 0.01 m BaCl2 (pHba)] with different soil : solution ratios (i.e. 1 : 1, 1 : 2.5, 1 : 5), the main objective being to study the influence of different electrolytes on the suspension effect of pH in calcareous soils. Soil pH measured in water showed significant differences between different dilution ratios and was highly influenced by the ‘suspension effect’. Other electrolytes (CaCl2, KCl, BaCl2) were little affected by the suspension effect, giving approximately stable values when pH was measured with and without stirring. High soil salinity appeared to suppress any suspension effect in a manner similar to electrolytes when added to non-saline soils.
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Palagina, I. A. "SOME ASPECTS OF MECHANISM OF SUCCINAMIDES INFLUENCE ON METABOLIC HOMEOSTASIS OF THE ORGANISM." Toxicological Review, no. 3 (June 28, 2018): 27–31. http://dx.doi.org/10.36946/0869-7922-2018-3-27-31.
Повний текст джерелаАнотація:
Succinate containing compounds possess many types of biological activity and are used for the development of drugs with the target and complex action. This paper is devoted to some aspects of the mechanism of succinamides’ action in a dose of 100 mg/kg. We studied the influence of the compound with antidiabetic properties, -phenylethylamide of 2-oxysuccinanyl acid ( -PhEA-OSAA), and its metabolites such as 2-hydroxyphenylsuccinamide (2-HPhSA) and β-phenylethylsuccinamide ( -PhESA) on the marker indicators of energetic metabolism (EM), antioxidant system (AOS) and nitric oxide (NO) metabolism in subacute experiment on rats. Studies have shown that the action of -FEA-OSAKA on metabolic homeostasis is realized through stimulation of EM, reduction of intensity of NO-synthase metabolism and weakening of the AOS. The nature of the action of -FES and 2-GFS, taking into account the indicators of the state of homeostasis, largely coincides with β-FEA-OSAKA. It was found that the key links in the mechanism of toxic action of succinamides are the effect on antioxidant potential, NO metabolism and energy processes.
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Prysiazhniuk, Stanislav, Oleksandr Pryimakov, Sergii Iermakov, Dmytro Oleniev, Jerzy Eider, and Natalija Mazurok. "Influence of weekly physical exercises on indicators of biological age of student's youth." Physical education of students 25, no. 1 (February 26, 2021): 58–66. http://dx.doi.org/10.15561/20755279.2021.0108.
Повний текст джерелаАнотація:
Background and Study Aim. The physical activity level of students is closely associated with ecological, hygienic, and socioeconomic facts. This is especially true during the COVID-19 pandemic, which has dramatically reduced the student opportunity to engage in regular physical activity. The purpose of the work is to study the influence of the weekly physical exercises on the indicators of biological age of students of higher education institutions of Ukraine.
Material and Methods. The study involved 409 students (182 boys and 227 girls), who were divided into experimental (87 boys and 117 girls) and control (95 boys and 110 girls) groups. The biological age (BA) of students was determined by means of Voitenko’s method using biomarkers of their physical status. Indices of the cardiovascular system (pulse, systolic, and diastolic blood pressure); respiratory system (vital capacity, the Hench and Stange test); central nervous system (static balancing); PHSA (personal health self-assessment) were studied. In addition, a questionnaire-based survey of students on their health self-assessment including 27 questions was carried out. Statistica 13.5 statistical software package was used to process the experimental material. Methods of variation statistics, correlation, and regression analysis were used. The coefficients of the Student t-test and Fisher’s F-test were calculated.
Results. In the process of pedagogical experiment, the positive impact of the author’s physical education program on BA of students of the experimental group (EG) was revealed: in boys, the positive dynamics of BA changes was detected already after four additional hours of performing exercises per week, whereas in girls – after six or more hours. The most pronounced changes in physical state, which determined BA decrease during academic year were noted in students with a weekly motor regime exceeding 6 hours. In boys of EG, the biological age decreased at the end of the experiment by 11,1 years (p < 0,001), whereas in girls – by 5,3 years (p < 0,001). No positive changes of BA were observed at the end of the experiment in students of the control group (CG), whose weekly regime of motor activity constituted 2 hours. In boys of EG, the decrease of BA is manifested after four additional hours of performing physical exercises per week, whereas in girls – after six or more hours. The most pronounced changes in BA indices during the academic year were noted in students of the experimental group with weekly motor regime exceeding 6 hours.
Conclusions. The developed mathematical models are recommended to be used for estimating, modelling, and predicting the biological age of students according to informative indices of physical state.
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Ishii-Hyakutake, Manami, Shoji Mizuno, and Takeharu Tsuge. "Biosynthesis and Characteristics of Aromatic Polyhydroxyalkanoates." Polymers 10, no. 11 (November 14, 2018): 1267. http://dx.doi.org/10.3390/polym10111267.
Повний текст джерелаАнотація:
Polyhydroxyalkanoates (PHAs) are polyesters synthesized by bacteria as a carbon and energy storage material. PHAs are characterized by thermoplasticity, biodegradability, and biocompatibility, and thus have attracted considerable attention for use in medical, agricultural, and marine applications. The properties of PHAs depend on the monomer composition and many types of PHA monomers have been reported. This review focuses on biosynthesized PHAs bearing aromatic groups as side chains. Aromatic PHAs show characteristics different from those of aliphatic PHAs. This review summarizes the types of aromatic PHAs and their characteristics, including their thermal and mechanical properties and degradation behavior. Furthermore, the effect of the introduction of an aromatic monomer on the glass transition temperature (Tg) of PHAs is discussed. The introduction of aromatic monomers into PHA chains is a promising method for improving the properties of PHAs, as the characteristics of aromatic PHAs differ from those of aliphatic PHAs.
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Bratkovskaya, E. L. "Resonances from PHSD." EPJ Web of Conferences 36 (2012): 00004. http://dx.doi.org/10.1051/epjconf/20123600004.
Повний текст джерела
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金, 冬雁. "一种兼具抗病毒活性及pHSA结合活性的蛋白——乙型肝炎病毒前S2肽段与人α2a型干扰素的融合蛋白". Chinese Science Bulletin 38, № 2 (1 січня 1993): 181–83. http://dx.doi.org/10.1360/csb1993-38-2-181.
Повний текст джерела
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Atmam, Elvira Zondra, and Hazra Yuvendius. "Konsumsi Energi Listrik Terhadap Perubahan Kecepatan Motor Induksi Tiga Phasa." SainETIn 4, no. 1 (December 31, 2019): 9–18. http://dx.doi.org/10.31849/sainetin.v4i1.3978.
Повний текст джерелаАнотація:
Motor induksi umumnya memiliki konstruksi sederhana, mudah dioperasikan, relatif lebih murah dalam perawatannya sehingga banyak digunakan di industri dan rumah tangga. Mesin listrik berupa motor induksi dilihat dari sumber tegangan salah satunya adalah jenis motor induksi tiga phasa. Motor induksi tiga phasa sering digunakan sebagai penggerak peralatan dengan kecepatan penuh atau kecepatan relatif konstan. Kecepatan motor induksi tiga phasa umumnya dapat dikendalikan yang salah satunya dengan pengaturan tegangan. Pengaturan atau pengendalian tegangan variabel pada motor induksi tiga phasa untuk memperoleh kecepatan yang berubah, dapat diperoleh dengan menggunakan ac voltage regulator tiga phasa. Perubahan sumber tegangan masukan yang variabel pada motor induksi tiga phasa akan mempengaruhi parameter motor induksi tiga phasa termasuk juga konsumsi atau penggunaan energi listrik. Dari hasil penelitian ini diperoleh konsumsi energi listrik motor induksi tiga phasa hubungan bintang tanpa beban dengan kecepatan 3000 rpm lebih tinggi sebesar 0,079 kWh (48%) atau Rp. 51,376 selama satu jam dibanding dengan kecepatan 2570 rpm, motor induksi tiga phasa hubungan bintang berbeban dengan kecepatan 2570 konsumsi energi listriknya lebih tinggi sebesar 0,124 kWh (22%) atau Rp. 167,648 dibanding kecepatan 3000 rpm, konsumsi energi listrik motor induksi tiga phasa hubungan delta tanpa beban dengan kecepatan 2570 rpm lebih tinggi sebesar 0,065 kWh (23%) atau Rp. 87,88 dibanding kecepatan 3000 rpm dan motor induksi tiga phasa hubungan delta berbeban dengan kecepatan 2570 konsumsi energi listriknya lebih tinggi sebesar 0,551 kWh (56%) atau Rp. 744,952 dibandingkan kecepatan 300 rpm.
Kata Kunci: Motor induksi tiga phasa, ac voltage regulator, energi listrik
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Godbole, Suchitra. "Methods for identification, quantification and characterization of polyhydroxyalkanoates." International Journal of Bioassays 5, no. 04 (April 22, 2016): 4977. http://dx.doi.org/10.21746/ijbio.2016.04.005.
Повний текст джерелаАнотація:
Polyhydroxyalkanoates (PHAs) are the polymers of hydroxyalkanoates that accumulate as a carbon/energy storage material in various microorganisms. PHAs have been attracting considerable attention as biodegradable substitutes for conventional polymers, because of their similar material properties to conventional plastics. A number of review articles on the general features of PHAs, the physiology, genetics and molecular biology, the development of PHAs having novel monomer constituents, production processes, biodegradation of PHAs are available. Recently much effort has been devoted to develop a process for the economical production of PHAs. The isolation, analysis and characterization of PHAs are important factors for any process development. A number of methods have been developed for the analysis of PHAs. This paper is an effort to compile the methods available for the identification, quantitative estimation and characterization of PHAs. The methods described in this paper include- staining reactions, spectrophotometric methods, infrared and FTIR spectroscopy, HPLC, gas chromatography and GC-MS analysis, NMR spectroscopy, flow cytometry and spectrofluorometry, molecular weight determination and thermal analysis. The methods have been discussed with their advantages and disadvantages. Recent developments in the analysis of PHAs have also been discussed.
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Atmam, Atmam. "PENGGUNAAN FILTER KAPASITIF PADA RECTIFIER SATU PHASA DAN TIGA PHASA MENGGUNAKAN POWER SIMULATOR (PSIM)." SainETIn 2, no. 1 (January 29, 2018): 18–26. http://dx.doi.org/10.31849/sainetin.v2i1.1667.
Повний текст джерелаАнотація:
Catu daya dengan tegangan arus searah ini dihasilkan dari pengubahan tegangan AC (Alternating Current)menjadi tegangan DC (Direct Current) yang biasa disebut dengan penyearah atau rectifier. Tegangan output awal dari sebuah rectifier belum merupakan tegangan DC murni dengan bentuk gelombang berupa garis lurus melainkan memiliki riak atau ripple yang akan berpengaruh terhadap peralatan elektronika serta dapat menimbulkan kerusakan pada peralatan elektronika tersebut. Tegangan output rectifier yang memiliki riak atau ripple perlu direduksi agar tidak mengganggu kerja peralatan elektronika yang tersambung dengan sumber tegangan DC tersebut. Salah satu cara yang dapat dilakukan adalah dengan memberikan filter diantaranya adalah filter kapasitif berupa pemasangan kapasitor pada sisi output dari rectifier satu phasa maupun rectifier tiga phasa. Dari Hasil penelitian ini diperoleh tegangan ripple untuk pemasangan filter kapasitif rectifier satu phasa dan tiga phasa sebesar 100μF/25V maka terlihat bahwa tegangan ripple rectifier tiga phasa lebih kecil yaitu 0,6241 Vpp dibandingan dengan tegangan ripple rectifier satu phasa sebesar 3,0843 Vpp. Tegangan ripple rectifier satu phasa dengan filter kapasitif sebesar 1000μF/25V adalah 0,3123 Vpp dan tegangan ripple rectifier tiga phasa filter kapasitif sebesar 1000μF/25V adalah 0,0701 Vpp sehingga tegangan ripple rectifier tiga phasa lebih kecil bila dibandingan dengan tegangan ripple rectifier satu phasa.
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Bonartsev, A. P., G. A. Bonartseva, I. V. Reshetov, K. V. Shaitan, and M. P. Kirpichnikov. "Application of Polyhydroxyalkanoates in Medicine and the Biological Activity of Natural Poly(3-Hydroxybutyrate)." Acta Naturae 11, no. 2 (June 15, 2019): 4–16. http://dx.doi.org/10.32607/20758251-2019-11-2-4-16.
Повний текст джерелаАнотація:
Biodegradable and biocompatible polymers, polyhydroxyalkanoates (PHAs), are actively used in medicine to produce a wide range of medical devices and dosage formulations. The medical industry mainly utilizes PHAs obtained by chemical synthesis, but interest in the medical application of natural PHAs obtained biotechnologically is also growing. Synthetic PHAs are the biomimetic analogs of bacterial poly(3-hydroxybutyrate) (PHB) and other natural PHAs. This paper addresses the issue of the presence of biological activity in synthetic and natural PHAs (stimulation of cell proliferation and differentiation, tissue regeneration) and their possible association with various biological functions of PHB in bacteria and eukaryotes, including humans.
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Breunig, Hans Joachim, Ali Soltani-Neshan, Karl Häberle, and Martin Dräger. "Synthese und Kristallstruktur von (PhSb)6 · 1,4-Dioxan, (PhSb)6 · Benzol und (PhSb)6 · Toluol. Oxidation von Silylstibanen zu Siloxistibanen / Synthesis and Crystal Structure of (PhSb)6 · 1,4-Dioxane, (PhSb)6 ·Benzene and (PhSb)6 ·Toluene. Oxidation of Silylstibanes to Siloxistibanes." Zeitschrift für Naturforschung B 41, no. 3 (March 1, 1986): 327–33. http://dx.doi.org/10.1515/znb-1986-0306.
Повний текст джерелаАнотація:
Slow air oxidation of PhSb(SiMe3)2 in 1,4-dioxane. benzene, or toluene gives (Me3Si)2O and crystals of (PhSb)6 · 1,4-dioxane, (PhSb)6 · benzene, or (PhSb)6· toluene, respectively. The crystal structure of the three isomorphous phases are reported. There are centrosymmetric Sb6 chairs with equatorial phenyl groups (total symmetry of the molecules approximately D3d, distances Sb-Sb 284 and Sb-C 216 pm. angles Sb-Sb -Sb 90°). The ring compounds are stabilized in forming stacks of (PhSb)ft molecules with short intermolecular Sb···Sb interactions (420 pm). The solvent molecules are needed for an optimum packing of these stacks. Air oxidation of PhSb(SiMe3)2 in the gas phase gives PhSb(OSiMe3)2. (Me3SiO)3Sb and Ph2SbOSiMe3 are formed, when Ph2SbSiMe3 is exposed to the air in an open flask. (Me3SiO)3Sb is also obtained from (Me3Si)3Sb and O2. Access of air to Ph2SbSiMe3 leads to 65% of Ph2SbOSiMe3.
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Chuang, S. H., C. F. Ouyang, H. C. Yuang, and S. J. You. "Phosphorus and polyhydroxyalkanoates variation in a combined process with activated sludge and biofilm." Water Science and Technology 37, no. 4-5 (February 1, 1998): 593–97. http://dx.doi.org/10.2166/wst.1998.0724.
Повний текст джерелаАнотація:
This study investigates variations of phosphorus and polyhydroxyalkanoates (PHAs) in a combined activated sludge - biofilm process, operating under various sludge retention times (5, 10 and 15 days) and different dissolved oxygen conditions (0.1, 0.5, 1.0 and 2.0 mg/l in aerobic stage). Experimental results indicate that phosphorus uptake closely corresponds to utilization of PHAs during anoxic and aerobic stages. Moreover, the sludge in the anoxic stage exhibits a higher PHAs utilization efficiency with respect to phosphorus uptake than sludge in the aerobic stage, when it is under low COD-SS loading conditions. The values of rP/PHAs, representing sludge capacity on phosphorus uptake, range from 0.1-1.0 mg P/mg PHAs. In addition, analyzing the distribution of 3-hydroxybutyrate (3HB), 3-hydroxy-2-methylbutyrate (3H2MB), 3-hydroxyvalerate (3HV) and 3-hydroxy-2-methylvalerate (3H2MV) reveals that 3HB and 3HV are the major components of PHAs. The values of 3HB/PHAs and 3HV/PHAs vary with COD-SS loading of the process. When F/M ratio increases, 3HV/PHAs value increases and 3HB/PHAs value decreases simultaneously. This phenomenon implies that more bacteria accumulated 3HV as storage matter under high COD-SS loading conditions. The kind of bacteria population shift would intensify the competition of “G bacteria” with polyphosphate accumulating organisms, possibly causing process deterioration during phosphorus removal.
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Abd alFattah Amara, Amro. "Polyhydroyalkanoates: from Basic Research and Molecular Biology to Application." IIUM Engineering Journal 9, no. 1 (September 29, 2010): 37–73. http://dx.doi.org/10.31436/iiumej.v9i1.95.
Повний текст джерелаАнотація:
This review describes the Polyhydroxyalkanoate (PHA), an intracellular biodegradable microbial polymer. PHAs is formed from different types of three hydroxyalkanoic acids monomers, each unit forms an ester bond with the hydroxyl group of the other one and the hydroxyl substituted carbon has R configuration. The C-3 atom in β position is branched with at least one carbon atom in the form of methyl group (C1) to thirteen carbons in the form of tridecyl (C13). This alkyl side chain is not necessarily saturated. PHAs are biosynthesized through regulated pathways by specific enzymes. PHAs are accumulated in bacterial cells from soluble to insoluble form as storage materials inside the inclusion bodies during unbalanced nutrition or to save organisms from reducing equivalents. PHAs are converted again to soluble components by PHAs depolymerases and the degraded materials enter various metabolic pathways. Until now, four classes of enzymes responsible for PHAs polymerization are known. PHAs were well studied regarding their promising applications, physical, chemical and biological properties. PHAs are biodegradable, biocompatible, have good material properties, renewable and can be used in many applications. The most limiting factor in PHAs commercialization is their high cost compared to the petroleum plastics. This review highlights the new knowledge and that established by the pioneers in this field as well as the factors, which affect PHAs commercialization.
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Evans, C. M., M. K. Conyers, A. S. Black, and G. J. Poile. "Effect of ammonium, organic amendments, and plant growth on soil pH stratification." Soil Research 36, no. 4 (1998): 641. http://dx.doi.org/10.1071/s97100.
Повний текст джерелаАнотація:
We studied the development of soil layers of different pH (strata) within the surface 10 cm of soil. Substrates which affect nitrogen transformations (ammonium sulfate, sucrose, and lucerne hay) were added to the soil to determine the effect of amendment on the development of pH stratification. A glasshouse experiment used soils of 3 different initial pH(0·01 CaCl2; pHCa) values: 4, 5, and 6. At the end of the experiment, soil was sampled in depth intervals of 0·5 cm between 0 and 2 cm depth and then 1-cm intervals between 2 and 10 cm depth. Soil pHCa decreased over time and pHCa changes could be explained by variations in the concentration of ammonium and nitrate, which were brought about by changes in the rate of mineralisation, nitrification, and plant uptake of nitrogen. Little stratification in soil pHCa was found within the 0–10 cm layer. This minimal stratification was considered to be due to the soil in the pots being a closed system where nitrate was not lost through leaching. A field trial was rotary hoed to a depth of approximately 10 cm to achieve adequate mixing of soil and amendments. Soil pHCa decreased over the 6 months of the growing season, ranging from 0·1 pHCa units in the control to 0·4 pHCa units in the hay amendment. Between the initial and final sampling times there was little change in soil pHCa in the surface 0–2 cm. The pHCa decreased in the layers between 2 and 10 cm, thus producing the stratification of soil pHCa. The growth of oats had little effect on the development of pHCa stratification. Decreases in the soil pHCa from the 0–2 cm to the 8–10 cm layer in the absence of plants were 0·22, 0·27, 0·30, and 0·51 for the control, added sucrose, added ammonium sulfate, and added hay amendments, respectively. The processes of mineralisation and nitrification were considered to be the major causes of change in soil pHCa. Stratification of pHCa in the field trial was attributed to nitrification followed by nitrate leaching in the open system.
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Dimashkieh, Haytham H., Jun Q. Mo, Josephine Wyatt-Ashmead, and Margaret H. Collins. "Pediatric Hepatic Angiosarcoma: Case Report and Review of the Literature." Pediatric and Developmental Pathology 7, no. 5 (September 2004): 527–32. http://dx.doi.org/10.1007/s10024-004-4041-x.
Повний текст джерелаАнотація:
Pediatric hepatic angiosarcoma (PHAS) is a rare tumor, which usually presents as a rapid enlargement of the liver. To date, surgery, chemotherapy, and radiotherapy have not improved the poor prognosis of PHAS with only three survivors reported. The histology of PHAS is distinct from adult angiosarcoma, because PHAS displays hypercellular whorls of sarcomatous cells, or “kaposiform” spindle cells, in addition to the general features of angiosarcoma. We report a case of PHAS that was treated with vascular ablation, chemotherapy, and liver transplantation. Lung metastases occurred 14 months posttransplant.
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Lu, Meng-Shan, Long-Li Lai, and Yung-Pin Tsai. "COMPARISON OF OPTIMUM CONDITIONS WHEN EXTRACTING PHAS FROM DIFFERENT WASTE SLUDGE SOURCES." Journal of Environmental Engineering and Landscape Management 26, no. 3 (October 9, 2018): 190–94. http://dx.doi.org/10.3846/16486897.2017.1411271.
Повний текст джерелаАнотація:
Biological wastewater treatment plants produce great amounts of sludge daily. It is a very big loading (cost) for treating the waste sludge. Polyhydroxyalkanoates are a family of polyhydroxyesters. The technologies of extracting PHAs from wasted sewage sludges of municipal wastewater, fermentation industry and husbandry were developed in the study. In the NaOCl/SDS extraction technology, the concentration of NaOCl and liquid-solid ratio are two essential factors directly influencing extraction efficiency. The experimental results verified under the optimal conditions for extracting PHAs, the content of recovered PHAs was 44.2±0.89 mgPHA/gVSS and the purity of recovered PHAs was >99.5 wt% for the waste sludge from municipal wastewater treatment plants. For fermentation industry sludge, under the adequate extraction conditions for PHAs recovery, the content and purity of recovered PHAs were 18.8±0.66 mgPHA/gVSS and 50.6±6.83 wt%, respectively. For husbandry sludge, the content and purity of recovered PHAs were 33.7±0.16 mgPHA/gVSS and 76.7±5.2 wt%, respectively.
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Bodine, DM, NE Seidel, KM Zsebo, and D. Orlic. "In vivo administration of stem cell factor to mice increases the absolute number of pluripotent hematopoietic stem cells." Blood 82, no. 2 (July 15, 1993): 445–55. http://dx.doi.org/10.1182/blood.v82.2.445.445.
Повний текст джерелаАнотація:
Abstract We have examined the effects of administration of stem cell-factor (SCF) on the number and distribution of pluripotent hematopoietic stem cells (PHSC) in normal mice. Using the competitive repopulation assay we found that in vivo administration of SCF increases the absolute number of PHSC per mouse threefold. The increased numbers of PHSC are found in the peripheral blood and spleen of the SCF-treated animals. The spleen and peripheral blood stem cells completely repopulated the erythroid, myeloid, and lymphoid lineages of irradiated or W/Wv hosts, similar to bone marrow PHSC. PHSC from the peripheral blood of SCF- treated mice have a lineage marker-negative, c-kit-positive phenotype that is indistinguishable from that of bone marrow PHSC. The increase in the absolute number of spleen PHSC is associated with efficient gene transfer to these cells without prior treatment with 5-fluorouracil. This is a US government work. There are no restrictions on its use.
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Bodine, DM, NE Seidel, KM Zsebo, and D. Orlic. "In vivo administration of stem cell factor to mice increases the absolute number of pluripotent hematopoietic stem cells." Blood 82, no. 2 (July 15, 1993): 445–55. http://dx.doi.org/10.1182/blood.v82.2.445.bloodjournal822445.
Повний текст джерелаАнотація:
We have examined the effects of administration of stem cell-factor (SCF) on the number and distribution of pluripotent hematopoietic stem cells (PHSC) in normal mice. Using the competitive repopulation assay we found that in vivo administration of SCF increases the absolute number of PHSC per mouse threefold. The increased numbers of PHSC are found in the peripheral blood and spleen of the SCF-treated animals. The spleen and peripheral blood stem cells completely repopulated the erythroid, myeloid, and lymphoid lineages of irradiated or W/Wv hosts, similar to bone marrow PHSC. PHSC from the peripheral blood of SCF- treated mice have a lineage marker-negative, c-kit-positive phenotype that is indistinguishable from that of bone marrow PHSC. The increase in the absolute number of spleen PHSC is associated with efficient gene transfer to these cells without prior treatment with 5-fluorouracil. This is a US government work. There are no restrictions on its use.
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Widiarsana, I. Made, I. Made Mataram, and Yanu Prapto Sudarmojo. "Identifikasi Jenis Gangguan pada Jaringan Transmisi Menggunakan Metode Jaring Syaraf Tiruan." Majalah Ilmiah Teknologi Elektro 17, no. 1 (May 22, 2018): 1. http://dx.doi.org/10.24843/mite.2018.v17i01.p01.
Повний текст джерелаАнотація:
Pada jaringan transmisi sering terjadi berbagai macam jenis gangguan, antara lain gangguan hubung singkat satu phasa ke tanah, gangguan hubung singkat phasa ke phasa, gangguan antar phasa ke tanah dan gangguan simetris. Pendeteksian terhadap gangguan tersebut dapat dilakukan dengan metode jaring syaraf tiruan. Jaring syaraf tiruan terdiri dari sejumlah elemen penghitung tak linier yang masing-masing dihubungkan secara paralel melalui suatu pembobot. Proses training pada jaring syaraf tiruan ini terdiri dari proses pelatihan terhadap gangguan hubung singkat satu phasa ke tanah, gangguan hubung singkat phasa dengan phasa, gangguan hubung singkat antar phasa dengan tanah, dan gangguan simetris. Proses pelatihan pada jaringan transmisi ini menggunakan konfigurasi 6 data intput, 10 hidden layer, 6 data target, dan 6 output (6-10-6-6). Hasil pelatihan menunjukkan bahwa nilai arus dan tegangan gangguan untuk semua jenis gangguan pada jaringan transmisi berhasil di bangkitkan, dimana output berupa nilai tegangan dan arus dari proses pelatihan akan disimpan dan dijadikan sebagai refrensi untuk menentukan jenis gangguan hubung singkat yang terjadi pada jaringan transmisi. Data hasil simulasi jaringan transmisi dapat dikatakan normal saat mendekati nilai output atau sebaliknya ketika jaringan transmisi mengalami gangguan hubung singkat.
[TURNITIN CHECK 75 19042017]
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Rangkuti, Riski Anda, Atmam Atmam, and Elvira Zondra. "Studi Pengaturan Kecepatan Motor Induksi Tiga Phasa Menggunakan Variable Speed Drive (VSD) Berbasis Programmable Logic Controller (PLC)." JURNAL TEKNIK 14, no. 1 (April 30, 2020): 121–28. http://dx.doi.org/10.31849/teknik.v14i1.2295.
Повний текст джерелаАнотація:
Motor induksi merupakan motor listrik arus bolak balik (AC) yang paling banyak digunakan saat ini, karena memiliki konstruksi yang sederhana, relatif murah serta mudah dalam pemeliharaannya. Motor induksi juga banyak digunakan untuk berbagai keperluan dalam proses produksi pada suatu industri. Dengan berkembangnya teknologi sistem kontrol salah satu cara yang dilakukan adalah dengan menggunakan kendali Variable Speed Drive (VSD) yang dihubungkan langsung dengan motor induksi 3 phasa untuk mengatur kecepatan, dan ditambah dengan menggunakan Programmable Logic Controller (PLC) yang berfungsi sebagai pengendali Variable Speed Drive (VSD) untuk mengatur kecepatan motor induksi 3 phasa. Kecepatan motor induksi tiga phasa saat tidak terkopel beban sebesar 2802 rpm dengan frekuensi 50 Hz, kecepatan 1681 rpm pada frekuensi 30 Hz dan kecepatan 840,6 rpm pada frekuensi 15 Hz. Dengan kondisi terkopel beban kecepatan motor induksi tiga phasa sebesar 1434 rpm dengan frekuensi 25,6 Hz, kecepatan 1462 rpm pada frekuensi 26,1 Hz dan kecepatan 1496 rpm pada frekuensi 26,6 Hz. Frekuensi berbanding lurus terhadap kecepatan motor induksi 3 phasa, semakin besar frekuensi yang masuk pada motor induksi 3 phasa maka akan semakin cepat putaran motor induksi 3 phasa tersebut.
Kata kunci : Motor Induksi 3 Phasa, Variable Speed Drive (VSD), Programmable Logic Controller (PLC).
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Jabeen, Asma, Rida Batool, and Nazia Jamil. "Micrococcus yunnanensis and Psychrobacter sp. as Potential Producers of Polymers from Hot Spring." Industria: Jurnal Teknologi dan Manajemen Agroindustri 11, no. 1 (April 30, 2022): 1–9. http://dx.doi.org/10.21776/ub.industria.2022.011.01.1.
Повний текст джерелаАнотація:
Polyhydroxyalkanoates (PHAs) and exopolysaccharides (EPSs) are biopolymers bacteria under nutrient-limiting conditions. In this study, bacterial strains were isolated from hot springs. Soil samples were collected from Tatta Pani, Azad Kashmir, Pakistan. Bacterial strains AJ2 and AJ3 were selected due to their ability to produce PHAs and EPSs. Phylogenetic analysis showed that strain AJ2 was Micrococcus yunnanensis and AJ3 was Psychrobacter sp. Three carbon sources (glucose, glycerol, and molasses) were used for polymer production. The effect of high pH (8) and high temperature (55 °C) was checked on PHAs and EPSs production. The highest yield of PHAs was given by strain AJ3 (89.43%) with molasses. When grown at 55 °C for 24 hours, strain AJ3 showed the highest PHAs accumulation, 79% with glucose. At alkaline pH 8, strain AJ3 gave 34% PHAs with molasses. The highest EPSs production was observed for strain AJ3. AJ3 gave 70g/L of EPSs with both glucose and glycerol. The amplification of the phaC gene was done to confirm the genetic basis of PHAs production. FTIR analysis showed clear bands at 1722 cm-1 and 2925 cm-1 representing the carbonyl and alkyl groups of PHAs, respectively.
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., Atmam, Zulfahri ., and Usaha Situmeang. "ANALISIS PENGARUH PERUBAHAN BESARAN KAPASITOR TERHADAP ARUS START MOTOR INDUKSI SATU PHASA." SainETIn 1, no. 1 (January 24, 2017): 1–8. http://dx.doi.org/10.31849/sainetin.v1i1.164.
Повний текст джерелаАнотація:
Penggunaan motor induksi jika dilihat dari sumber tegangannya, salah satunya adalah jenis motor induksi satu phasa. Motor induksi satu phasa dengan jenis motor kapasitor permanen atau disebut juga dengan motor kapasitor running banyak digunakan untuk keperluan rumah tangga sebagai penggerak pada pompa air, kipas angin dan lain sebagainya. Motor induksi satu phasa tidak dapat start sendiri untuk start awal. Untuk itu motor induksi satu phasa dilengkapi dengan sebuah kumparan bantu yang terhubung seri dengan kapasitor yang besaran kapasitornya sesuai untuk starting motor induksi satu phasa. Apabila kapasitor yang digunakan, besaran kapasitornya tidak sesuai atau kapasitor mengalami kerusakan maka akan mengakibatkan arus start tinggi dan motor akan mengalami gangguan bahkan kerusakan. Oleh karena itu, perlu dilakukan penelitian untuk menganalisa perubahan besaran kapasitor terhadap arus start motor induksi satu phasa kondisi tanpa beban atau beban nol. Dari penelitian ini diperoleh arus start motor induksi satu phasa dengan kapasitor 8 µF sebesar 3,83 Amper, kapasitor 20 µF sebesar 3,71 Amper dan kapasitor 100 µF sebesar 6,06 Amper. Arus nominal dari motor induksi satu phasa, untuk kapasitor 8 µF adalah 1,06 Amper, kapasitor 20 µF, arus nominalnya sebesar 1,98 Amper dan kapasitor 100 µF, arus nominal sebesar 5,6 Amper, maka perubahan besaran kapasitor akan mengakibatkan arus nominal semakin besar, sehingga besaran kapasitor yang tepat adalah sebesar kapasitor 8 µF untuk motor induksi satu phasa.
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Reddy, V. Uttej Nandan, S. V. Ramanaiah, M. Venkateswar Reddy, and Young-Cheol Chang. "Review of the Developments of Bacterial Medium-Chain-Length Polyhydroxyalkanoates (mcl-PHAs)." Bioengineering 9, no. 5 (May 21, 2022): 225. http://dx.doi.org/10.3390/bioengineering9050225.
Повний текст джерелаАнотація:
Synthetic plastics derived from fossil fuels—such as polyethylene, polypropylene, polyvinyl chloride, and polystyrene—are non-degradable. A large amount of plastic waste enters landfills and pollutes the environment. Hence, there is an urgent need to produce biodegradable plastics such as polyhydroxyalkanoates (PHAs). PHAs have garnered increasing interest as replaceable materials to conventional plastics due to their broad applicability in various purposes such as food packaging, agriculture, tissue-engineering scaffolds, and drug delivery. Based on the chain length of 3-hydroxyalkanoate repeat units, there are three types PHAs, i.e., short-chain-length (scl-PHAs, 4 to 5 carbon atoms), medium-chain-length (mcl-PHAs, 6 to 14 carbon atoms), and long-chain-length (lcl-PHAs, more than 14 carbon atoms). Previous reviews discussed the recent developments in scl-PHAs, but there are limited reviews specifically focused on the developments of mcl-PHAs. Hence, this review focused on the mcl-PHA production, using various carbon (organic/inorganic) sources and at different operation modes (continuous, batch, fed-batch, and high-cell density). This review also focused on recent developments on extraction methods of mcl-PHAs (solvent, non-solvent, enzymatic, ultrasound); physical/thermal properties (Mw, Mn, PDI, Tm, Tg, and crystallinity); applications in various fields; and their production at pilot and industrial scales in Asia, Europe, North America, and South America.
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Kaewkannetra, Pakawadee, and Sarunya Promkotra. "Microstructural Evolution of Synthesized Polyhydroxyalkanoates (PHAs) Corresponding to their Blends." Defect and Diffusion Forum 312-315 (April 2011): 688–93. http://dx.doi.org/10.4028/www.scientific.net/ddf.312-315.688.
Повний текст джерелаАнотація:
Biopolymers of polyhydroxyalkanoates (PHAs) are produced by pure bacterial strain of Alcaligenes eutrophus TISTR 1095 via batch fermentation using sugarcane juice as a carbon source, and yielded up to 21% (w/w) after recovery process. The PHAs are blended with bio-based materials such as tapioca and corn starch including glycerol and methanol to improve their microstructures. The combination of various plasticizers with PHAs is studied in different ratios. The PHAs and starch are mixed for 3% w/v and 30% w/v in hot chloroform, respectively. The varieties of PHAs to starch solution ratios are situated for casting as of films. The PHAs blended films are characterized by polarized light microscopy, differential scanning calorimetry (DSC) and x-ray diffractometry (XRD). The initial PHAs indicate remarkably crystalline structure with cross-polarized light on optical microscope. Macroscopic scales of their films are very brittle and flexible. However, their microscopic scales present small patches of particular components from each starch. Immiscibility of the blends is gradually increased on adding the starch portions. Additional glycerol shows more strongly interfacial adhesion between starch and PHAs, and methanol produces specifically thin films. Melting transition temperatures of blended films are slightly higher than the biosynthesized PHAs as examined by DSC. Corn starch mixture causes highly brittle films than tapioca mixtures, which indicates poor adhesion between corn starch and the PHAs. This result is correspondent to their highly crystallinity from diffractogram. Microstructural evolution of the blended films is increased slightly crystallinity by the solution casting.
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MANI, Ali R., Ananth S. PANNALA, Nelson N. ORIE, Richard OLLOSSON, David HARRY, Catherine A. RICE-EVANS, and Kevin P. MOORE. "Nitration of endogenous para-hydroxyphenylacetic acid and the metabolism of nitrotyrosine." Biochemical Journal 374, no. 2 (September 1, 2003): 521–27. http://dx.doi.org/10.1042/bj20030670.
Повний текст джерелаАнотація:
Reactive nitrogen species, such as peroxynitrite, can nitrate tyrosine in proteins to form nitrotyrosine. Nitrotyrosine is metabolized to 3-nitro-4-hydroxyphenylacetic acid (NHPA), which is excreted in the urine. This has led to the notion that measurement of urinary NHPA may provide a time-integrated index of nitrotyrosine formation in vivo. However, it is not known whether NHPA is derived exclusively from metabolism of nitrotyrosine, or whether it can be formed by nitration of circulating para-hydroxyphenylacetic acid (PHPA), a metabolite of tyrosine. In the present study, we have developed a gas chromatography MS assay for NHPA and PHPA to determine whether or not NHPA can be formed directly by nitration of PHPA. Following the injection of nitrotyrosine, 0.5±0.16% of injected dose was recovered unchanged as nitrotyrosine, and 4.3±0.2% as NHPA in the urine. To determine whether or not NHPA could be formed by the nitration of PHPA, deuterium-labelled PHPA ([2H6]PHPA) was injected, and the formation of deuterated NHPA ([2H5]NHPA) was measured. Of the infused [2H6]PHPA, 78±2% was recovered in the urine unchanged, and approx. 0.23% was recovered as [2H5]NHPA. Since the plasma concentration of PHPA is markedly higher than free nitrotyrosine (approx. 400-fold), the nitration of high-circulating endogenous PHPA to form NHPA becomes very significant and accounts for the majority of NHPA excreted in urine. This is the first study to demonstrate that NHPA can be formed by nitration of PHPA in vivo, and that this is the major route for its formation.
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Bayliss, Cathy, Bonnie Lasby, Janet M. Wood, Ran Lifshitz, and Gerry L. Brown. "Mutant derivatives of Pseudomonas putida GR12-2R3 defective in nutrient utilization or cell surface structures show reduced ability to promote canola root elongation." Canadian Journal of Microbiology 39, no. 12 (December 1, 1993): 1111–19. http://dx.doi.org/10.1139/m93-168.
Повний текст джерелаАнотація:
Pseudomonas putida GR12-2R3 is a rifampicin-resistant derivative of a cold-tolerant, nitrogen-fixing bacterium isolated from the roots of grasses growing in the Canadian high arctic. It colonizes canola (Brassica campestris) roots and promotes canola root and shoot growth under gnotobiotic conditions and in the field. TnphoA insertion mutagenesis was used to isolate derivatives of strain GR12-2R3 that had reduced abilities to promote canola root elongation (PRE− mutants). Within a pool of 10 290 TnphoA insertion mutants, 1.4% expressed active PhoA fusion proteins (PhoA+). Among 20 PhoA+ mutants, 6 were PRE− and 4 of those strains secreted PhoA activity into the culture medium. PhoA+ strain PG269 showed PhoA activity, 25% cell associated, that was induced by canola seed exudate. The ability of this strain to promote canola root elongation was similar to that of the parent strain. Like other pseudomonads, strain GR12-2R3 utilizes a wide range of sugars, amino acids, and other compounds as carbon and nitrogen sources. Twenty-one TnphoA insertion mutants, all PhoA−, were unable to utilize a specific nutrient. That group included strains that could not utilize arabinose (Ara−, three mutants) or glycerol and other compounds (Csu−, three mutants) as carbon source and strains that could not utilize glycine (Gut−, eight mutants), histidine (Hut−, three mutants), or proline (Put−, four mutants) as nitrogen source. One Ara− mutant, three Gut− mutants, and one Csu− mutant were PRE−. Five of the mutant strains examined in detail (two PhoA− PRE−, one PhoA− PRE+, one PhoA+ PRE−, and one PhoA+ PRE+) grew less well than strain GR12-2R3 in LB and (or) seed exudate medium. Further characterization of the TnphoA target genes in selected PRE− strains is expected to yield additional insight regarding the molecular basis for the interaction between P. putida GR12-2R3 and canola.Key words: Pseudomonas putida, plant growth promoting rhizobacterium, TnphoA.
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Zhou, Yanwen, Tingxi Zhang, Shengyan Jin, Siyu Chen, and Yinlong Zhang. "Effects of Escherichia coli Alkaline Phosphatase PhoA on the Mineralization of Dissolved Organic Phosphorus." Water 13, no. 23 (November 23, 2021): 3315. http://dx.doi.org/10.3390/w13233315.
Повний текст джерелаАнотація:
Alkaline phosphatases, which play the key role in the mineralization of organic phosphorus, have been grouped into three distinct families, PhoA, PhoX, and PhoD. PhoA is still an important component of the Pho regulon for many microbes although its distribution is not as wide as that of PhoX and PhoD. However, several questions remain unclear about the effect of PhoA mineralization of dissolved organic phosphorus. In this study, the role of Escherichia coli alkaline phosphatase PhoA (hereinafter referred to as PhoA) in the mineralization of different organic phosphorus including phosphate monoesters, phosphate diesters, and phytic acids was investigated. The influence of the reaction time, organic phosphorus concentration, and L-amino acid on PhoA mineralization was examined. The results show that PhoA specifically hydrolyzes phosphate monoesters except for phytic acid and the optimal reaction time is around 12 h. The PhoA mineralization rate of glucose 6-phosphate disodium (G6P), 5′-adenosine monophosphate (AMP), and sodium glycerophosphate (BGP) significantly decreased by 38.01%, 55.31%, and 57.08%, respectively (p < 0.01), while the concentration of organic phosphorus increased from 0.50 to 5.00 mg/L. Overall, L-amino acids inhibited PhoA mineralization in a concentration-independent manner. The inhibitory effect of neutral amino acids serine (L-Ser) and tyrosine (L-Tyr) was significantly higher than that of basic amino acids arginine (L-Arg), lysine (L-Lys), and histidine (L-His). All the five amino acids can inhibit PhoA mineralization of AMP, with the highest inhibition rate observed for L-Tyr (23.77%), the lowest—for L-Arg (1.54%). Compared with other L-amino acids, L-Tyr has the highest G6P and BGP mineralization inhibition rate, with the average inhibition rates of 12.89% and 11.65%, respectively. This study provides meaningful information to better understand PhoA mineralization.
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Orlic, D., R. Fischer, S. Nishikawa, AW Nienhuis, and DM Bodine. "Purification and characterization of heterogeneous pluripotent hematopoietic stem cell populations expressing high levels of c-kit receptor." Blood 82, no. 3 (August 1, 1993): 762–70. http://dx.doi.org/10.1182/blood.v82.3.762.762.
Повний текст джерелаАнотація:
Abstract Mouse pluripotent hematopoietic stem cells (PHSC) were fractionated based on size and density using counterflow centrifugal elutriation (CCE). These heterogeneous PHSC populations were further enriched by subtraction of cells with lineage-specific markers (Lin-) followed by positive sorting for c-kit expression. The cells were characterized for their functional and biochemical properties. We defined a subpopulation of c-kit-positive cells that expressed high numbers of c-kit receptors (c-kitBR). One hundred c-kitBR cells from either low- or higher-density fractions were sufficient to repopulate the lymphohematopoietic system in WBB6F1-W/Wv (W/Wv) recipients, whereas no PHSC were found in cells with low (c-kitDULL) or no (c-kitNEG) c-kit expression. Lin- c-kitBR cells were separated into RhoDULL and RhoBR subsets based on their ability to efflux rhodamine 123 (Rho). The PHSC were concentrated in Lin- c-kitBR RhoDULL cells and the number of Lin- c-kitBR RhoBR cells correlated directly with the number of day 12 colony-forming unit- spleen (CFU-S12) in each fraction. We were not able to enrich further for PHSC using monoclonal antibodies to the cell-surface markers AA4.1 or CD4, which have been used by others to isolate PHSC. The small, low- density Lin- c-kitBR subset contained PHSC and few CFU-S12. This enabled us to assay PHSC for expression of the flk-2 gene, which encodes a tyrosine kinase receptor present on fetal liver PHSC. Purified RNA from the low-density Lin- c-kitBR subset did not contain flk-2 mRNA. We suggest that AA4.1, CD4 and flk-2 are expressed as stage- specific markers on PHSC in cell cycle.