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Vaisman, Alon, Michael Jula, Jessica Wagner y Lisa G. Winston. "Association Between Hospital-Onset Clostridium difficile infection and Admission to a Multi-Bed Room: A Case–control Study". Open Forum Infectious Diseases 4, suppl_1 (2017): S400. http://dx.doi.org/10.1093/ofid/ofx163.1000.
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Abstract Background Few studies have directly examined the link between assignment to a multi-bed vs. single-bed room and the risk for hospital onset C. difficileinfection (HO-CDI). Therefore, in this case–control study, we investigated whether assignment to a single-bed room reduced the risk of HO-CDI in adult inpatients on medical/surgical floors. Methods Consecutive cases of HO-CDI, defined as adult patients admitted to San Francisco General Hospital with a new positive C. difficile stool test >72 hours after admission, were identified for the period between January 1, 2010 to December 31, 2015. Patients who first tested positive for C. difficilein the ICU or who had a history of CDI within the last 12 months were excluded. Controls were selected from the general medical/surgical inpatient population using incidence density sampling and matched to cases on the basis of admission unit and length of admission. A multi-bed room was defined as any room with one or more roommates. A multivariate cox proportional hazard model was used to estimate the relationship between room assignment (single vs. multi-bed) and development of HO-CDI. Variables included in the model, on the basis of a directed acyclic graph, were length of admission, HIV infection, and age. Results 184 cases and 373 controls were identified during the study period. The median ages of cases and controls were 60 years and 56 years, and mean Charlson comorbidity scores were 3.8 and 3.7, respectively. The hazard ratio for the development HO-CDI associated with multi-bed room exposure was 2.32 (P = 0.03) with a 95% CI for the hazard ratio of 1.05 to 5.17. Conclusion In this study, assignment of patients to multi-bed rooms on general medical and surgical wards was associated with an increased hazard for the development of HO-CDI. This finding, especially if confirmed in other institutions, could have implications for patient room assignment and hospital design. Disclosures All authors: No reported disclosures.
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Vaisman, Alon, Michael Jula, Jessica Wagner y Lisa G. Winston. "Examining the association between hospital-onset Clostridium difficile infection and multiple-bed room exposure: a case-control study". Infection Control & Hospital Epidemiology 39, n.º 9 (31 de julio de 2018): 1068–73. http://dx.doi.org/10.1017/ice.2018.163.
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AbstractObjectiveTo determine whether assignment to a multiple-bed room increased the risk of hospital-onset C. difficile diarrhea (HO-CDI).DesignCase-control study.SettingSan Francisco General Hospital and Trauma Center.PopulationAdult general medical and surgical inpatients.MethodsConsecutive cases of HO-CDI were identified between January 1, 2010, and December 31, 2015. To investigate the effect of multiple-bed room exposure both at admission and at the time of symptom onset, 2 sets of controls were selected from the general medical/surgical inpatient population using incidence density sampling. Conditional logistic regression was used to estimate the relationship between room assignment (single bed vs multiple beds) and the development of HO-CDI.ResultsIn total, 187 cases were identified and matched with 512 and 515 controls for the admission and at-diagnosis analyses, respectively. The adjusted rate ratio (RR) associated with the development HO-CDI associated with multiple-bed room exposure during the 7 and 14 days immediately prior to HO-CDI diagnosis were 1.08 (95% confidence interval [CI], 0.93–1.25; P=.31) and 0.96 (95% CI, 0.93–1.18; P=.12), respectively. Furthermore, no significant association was detected in the analysis of the first 7 and 14 days after case admission or among patients with Charlson comorbidity scores ≥4 in either period.ConclusionAssignment of patients to multiple-bed rooms on general medical and surgical wards was not associated with an increased risk in the development of HO-CDI. Future investigation should be performed with larger cohorts in multiple sites to more definitively address the question because this issue could have implications for patient room assignment and hospital design.
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Krzyminiewski, R. y A. Lund. "ENDOR Studies of X-Irradiated Single Crystals of Sulphamethoxazole". Zeitschrift für Naturforschung A 47, n.º 9 (1 de septiembre de 1992): 950–54. http://dx.doi.org/10.1515/zna-1992-0905.
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Abstract Single crystals of sulphamethoxazole were X-irradiated at 273 K. ESR and ENDOR spectra were obtained at 100 K. The free radicals stable at room temperature are formally formed by abstraction of a hydrogen atom from the methyl group of the molecule. The unpaired electron is delocalized in the isoxazole ring. The assignment is supported by comparisons of spin densities obtained experimentally and by semiempirical molecular orbital calculations
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Nikolić, P. M., S. Đurić, K. M. Paraskevopoulos, T. T. Zorba, D. Luković, S. Savić, V. Blagojević y M. V. Nikolić. "Infrared reflectance of single-crystal jarandolite, CaB3O4(OH)3". Mineralogical Magazine 71, n.º 3 (junio de 2007): 273–83. http://dx.doi.org/10.1180/minmag.2007.071.3.273.
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AbstractPolarized far- and mid-infrared reflectance spectra were measured at room temperature for the new mineral species jarandolite, CaB3O4(OH)3, for the two principal directions. Thirty three vibration modes for and 32 for were observed and analysed numerically. Symmetry analysis predicts 41 and 40 vibration modes that include lattice and O–H modes. Mode assignment was made based on the structure of jarandolite. The values of the mode frequencies (ωTO), the damping factors (γ) and the oscillator strength (S) of each oscillator were obtained by fitting to a Lorentz model.
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Pujiyanti, Indah. "ALTERNATIF TEKNIK PASSIVE COOLING YANG EFISIEN PADA RUANG AUDITORIUM GEDUNG B UNIVERSITAS ‘AISYIYAH YOGYAKARTA". Jurnal Arsitektur dan Perencanaan (JUARA) 1, n.º 1 (6 de febrero de 2018): 43–57. http://dx.doi.org/10.31101/juara.v1i1.364.
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Abstract: The title of this paper research result is “The Passive Cooling Alternatif Technique Which Is Efficient In Auditorium Room ‘Aisyiyah Yogyakarta University. The problem which is going to be discussed in this final assignment research is to find the passive cooling technique which is applicable and effective to thermal comfort aspect for auditorium room ‘Aisyiyah Yogyakarta University. The goal which is going to be achieved in this final assignment is to know the passive cooling technique which is applicableand effective to thermal comfort aspect for auditorium room ‘Aisyiyah Yogyakarta University.The research method is conducted by direct observation on sample. Then the research model is made according to observation result. Then, the research model was tested by ecotect software to measure the temperature made by each model. The data got from the measurement were analyzed for thermal quality.Based on the analysis result, it is known that temperature in auditorium room ‘Aisyiyah Yogyakarta University until 30 celcius and that is not recommendation for comfortable room. Passive cooling techniques which are applicable for auditorium room ‘Aisyiyah Yogyakarta University are ventilative cooling and mass effect cooling (single banked room). It is also known that the effective passive cooling technique is mix-ventilation type with ratio ventilation more than 1:6,79. It is also known that there is a relation between room volume percentages which is passed by air stream with its air temperature in the room.Keywords: passive cooling technique, applicable, effective, auditorium room, UNISA
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Holleis, Edgar y Christoph Grimm. "Address Assignment in Indoor Wireless Networks Using Deterministic Channel Simulation". ISRN Sensor Networks 2013 (1 de septiembre de 2013): 1–13. http://dx.doi.org/10.1155/2013/495653.
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A crucial step during commissioning of wireless sensor and automation networks is assigning high-level node addresses (e.g., floor/room/fixture) to nodes mounted at their respective location. This address assignment typically requires visiting every single node prior to, during, or after mounting. For large-scale networks it also presents a considerable logistical effort. This paper describes a new approach to automatically assign high-level addresses without visiting every node. First, the wireless channel is simulated using a deterministic channel simulation in order to obtain node-to-node estimates of path loss. Next, the channel is measured by a precommissioning test procedure on the live network. In a third step, results from measurements and simulation are condensed into graphs and matched against each other. The resulting problem, identified as weighted graph matching, is solved heuristically. Viability of the approach and its performance is demonstrated by means of a publicly available test data set, which the algorithm is able to solve flawlessly. Further points of interest are the conditions that lead to high quality address assignments.
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Bouzid, Donia, Benoit Visseaux, Anne Perozziello, Xavier Lescure, Xavier Duval, Enrique Casalino y Jean Christophe Lucet. "Factors associated with single-room assignment among patients admitted through the emergency department during influenza epidemics". PLOS ONE 15, n.º 8 (7 de agosto de 2020): e0237214. http://dx.doi.org/10.1371/journal.pone.0237214.
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Ferroni, Lorenzo, Costanza Baldisserotto, Martina Giovanardi, Laura Pantaleoni, Tomas Morosinotto y Simonetta Pancaldi. "Revised assignment of room-temperature chlorophyll fluorescence emission bands in single living cells of Chlamydomonas reinhardtii". Journal of Bioenergetics and Biomembranes 43, n.º 2 (19 de febrero de 2011): 163–73. http://dx.doi.org/10.1007/s10863-011-9343-x.
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Chopde, A. M. y Manish Arote. "Automated and Efficient Hotel Management System". Journal of Information Technology and Cryptography 1, n.º 1 (20 de junio de 2023): 22–30. http://dx.doi.org/10.48001/joitc.2023.1122-30.
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The hotel administrator and receptionist can manage all hotel operations online using the desktop-based application known as the hotel management system. Being a very busy individual, the hotel administrator or receptionist does not have time to sit down and oversee all actions manually on paper. He now has the ability and freedom to control the complete system from a single web platform thanks to this programme. It oversees and keeps up the hotel's records of guests, accommodations, staff, and drivers. The project aims to keep the daily state of customer admission/vacation, employee list, room data, etc. The primary goal of this project is to offer hotels a way to handle most of their operations using computerized processes. This software will assist the administrator in managing client information, room assignment information, payment information, driver information, reserving rooms of two distinct types, etc. With the aid of the NetBeans IDE, it is constructed in the Java programming language. Java is used for its frontend and MySQL for its backend.
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ATREI, A., U. BARDI, E. ZANAZZI, G. ROVIDA, M. SAMBI y G. GRANOZZI. "STRUCTURE OF A SINGLE ATOMIC LAYER OF NICKEL DEPOSITED ON THE Pt(111) SURFACE DETERMINED BY LOW ENERGY ELECTRON DIFFRACTION". Surface Review and Letters 06, n.º 02 (abril de 1999): 213–17. http://dx.doi.org/10.1142/s0218625x9900024x.
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The structure of ultrathin films of Ni deposited at room temperature on the Pt (111) surface has been determined by low energy electron diffraction (LEED) intensity analysis. The first monolayer of Ni grows pseudomorphically on Pt (111) despite the 11% mismatch between the lattice parameters of nickel and platinum. The results of the analysis also show that the Ni atoms occupy face-centered-cubic sites on the substrate surface. These results in part confirm previous data obtained by X-ray photoelectron diffraction, but also provide more reliable data on the site assignment.
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Bertuzzi, Andrea, Alison Martin, Nicola Clarke, Cassandra Springate, Rachel Ashton, Wayne Smith, Andi Orlowski y Duncan McPherson. "Clinical, humanistic and economic outcomes, including experiencing of patient safety events, associated with admitting patients to single rooms compared with shared accommodation for acute hospital admissions: a systematic review and narrative synthesis". BMJ Open 13, n.º 5 (mayo de 2023): e068932. http://dx.doi.org/10.1136/bmjopen-2022-068932.
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ObjectivesAssess the impact of single rooms versus multioccupancy accommodation on inpatient healthcare outcomes and processes.DesignSystematic review and narrative synthesis.Data sourcesMedline, Embase, Google Scholar and the National Institute for Health and Care Excellence website up to 17 February 2022.Eligibility criteriaEligible papers assessed the effect on inpatients staying in hospital of being assigned to a either a single room or shared accommodation, except where that assignment was for a direct clinical reason like preventing infection spread.Data extraction and synthesisData were extracted and synthesised narratively, according to the methods of Campbellet al.ResultsOf 4861 citations initially identified, 145 were judged to be relevant to this review. Five main method types were reported. All studies had methodological issues that potentially biased the results by not adjusting for confounding factors that are likely to have contributed to the outcomes. Ninety-two papers compared clinical outcomes for patients in single rooms versus shared accommodation. No clearly consistent conclusions could be drawn about overall benefits of single rooms. Single rooms were most likely to be associated with a small overall clinical benefit for the most severely ill patients, especially neonates in intensive care. Patients who preferred single rooms tended to do so for privacy and for reduced disturbances. By contrast, some groups were more likely to prefer shared accommodation to avoid loneliness. Greater costs associated with building single rooms were small and likely to be recouped over time by other efficiencies.ConclusionsThe lack of difference between inpatient accommodation types in a large number of studies suggests that there would be little effect on clinical outcomes, particularly in routine care. Patients in intensive care areas are most likely to benefit from single rooms. Most patients preferred single rooms for privacy and some preferred shared accommodation for avoiding loneliness.PROSPERO registration numberCRD42022311689.
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Schwarb, Hillary, Curtis L. Johnson, Michael R. Dulas, Matthew D. J. McGarry, Joseph L. Holtrop, Patrick D. Watson, Jane X. Wang, Joel L. Voss, Bradley P. Sutton y Neal J. Cohen. "Structural and Functional MRI Evidence for Distinct Medial Temporal and Prefrontal Roles in Context-dependent Relational Memory". Journal of Cognitive Neuroscience 31, n.º 12 (diciembre de 2019): 1857–72. http://dx.doi.org/10.1162/jocn_a_01454.
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Declarative memory is supported by distributed brain networks in which the medial-temporal lobes (MTLs) and pFC serve as important hubs. Identifying the unique and shared contributions of these regions to successful memory performance is an active area of research, and a growing literature suggests that these structures often work together to support declarative memory. Here, we present data from a context-dependent relational memory task in which participants learned that individuals belonged in a single room in each of two buildings. Room assignment was consistent with an underlying contextual rule structure in which male and female participants were assigned to opposite sides of a building and the side assignment switched between buildings. In two experiments, neural correlates of performance on this task were evaluated using multiple neuroimaging tools: diffusion tensor imaging (Experiment 1), magnetic resonance elastography (Experiment 1), and functional MRI (Experiment 2). Structural and functional data from each individual modality provided complementary and consistent evidence that the hippocampus and the adjacent white matter tract (i.e., fornix) supported relational memory, whereas the ventromedial pFC/OFC (vmPFC/OFC) and the white matter tract connecting vmPFC/OFC to MTL (i.e., uncinate fasciculus) supported memory-guided rule use. Together, these data suggest that MTL and pFC structures differentially contribute to and support contextually guided relational memory.
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Rebollar, Esther, Jorge Bañuelos, Santiago de la Moya, Julien Eng, Thomas Penfold y Inmaculada Garcia-Moreno. "A Computational-Experimental Approach to Unravel the Excited State Landscape in Heavy-Atom Free BODIPY-Related Dyes". Molecules 27, n.º 15 (22 de julio de 2022): 4683. http://dx.doi.org/10.3390/molecules27154683.
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We performed a time-gated laser-spectroscopy study in a set of heavy-atom free single BODIPY fluorophores, supported by accurate, excited-state computational simulations of the key low-lying excited states in these chromophores. Despite the strong fluorescence of these emitters, we observed a significant fraction of time-delayed (microseconds scale) emission associated with processes that involved passage through the triplet manifold. The accuracy of the predictions of the energy arrangement and electronic nature of the low-lying singlet and triplet excited states meant that an unambiguous assignment of the main deactivation pathways, including thermally activated delayed fluorescence and/or room temperature phosphorescence, was possible. The observation of triplet state formation indicates a breakthrough in the “classic” interpretation of the photophysical properties of the renowned BODIPY and its derivatives.
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Videnova-Adrabinska, Veneta, Jan Baran, Henryk Ratajczak y William J. Orville-Thomas. "Infrared and Raman polarized spectra of ammonium hydrogen bis(trichloroacetate) single crystal". Canadian Journal of Chemistry 63, n.º 12 (1 de diciembre de 1985): 3597–604. http://dx.doi.org/10.1139/v85-591.
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The polarized infrared and Raman spectra of ammonium hydrogen bis(trichloroacetate) single crystal have been investigated in the 4000–350 cm−1 and 4000–10 cm−1 range, respectively. The infrared spectra have been measured at room and low temperatures. An assignment of the bands in terms of approximate type of motion is given. The asymmetric stretching vibration, vaOHO, of the strong hydrogen bond gives rise to a very broad infrared absorption, with a maximum around 800 ± 50 cm−1, which is polarized strictly along a tetragonal Z(c) direction of this crystal. For this vibration a correlation field (Davydov or factor group) splitting is not observed. The out-of-plane deformation vibration, γOHO, obeys selection rules for the C2 site symmetry group. This result and also an interpretation of the vC=O vibration strongly suggest that a potential energy function of the strong hydrogen bond has a single symmetric minimum.
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Ciupa-Litwa, Aneta, Maciej Ptak, Edyta Kucharska, Jerzy Hanuza y Mirosław Mączka. "Vibrational Properties and DFT Calculations of Perovskite-Type Methylhydrazinium Manganese Hypophosphite". Molecules 25, n.º 21 (9 de noviembre de 2020): 5215. http://dx.doi.org/10.3390/molecules25215215.
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Recently discovered hybrid perovskites based on hypophosphite ligands are a promising class of compounds exhibiting unusual structural properties and providing opportunities for construction of novel functional materials. Here, we report for the first time the detailed studies of phonon properties of manganese hypophosphite templated with methylhydrazinium cations ([CH3NH2NH2][Mn(H2PO2)3]). Its room temperature vibrational spectra were recorded for both polycrystalline sample and a single crystal. The proposed assignment based on Density Functional Theory (DFT) calculations of the observed vibrational modes is also presented. It is worth noting this is first report on polarized Raman measurements in this class of hybrid perovskites.
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Sharma, Neeraj, Rene B. Macquart, Maxim Avdeev, Mogens Christensen, Garry J. McIntyre, Yu-Sheng Chen y Chris D. Ling. "Re-investigation of the structure and crystal chemistry of the Bi2O3–W2O6 `type (Ib)' solid solution using single-crystal neutron and synchrotron X-ray diffraction". Acta Crystallographica Section B Structural Science 66, n.º 2 (26 de febrero de 2010): 165–72. http://dx.doi.org/10.1107/s0108768110001874.
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Single crystals of composition Bi35.66W4.34O66.51 (or Bi8.2WO15.3, bismuth tungsten oxide), within the type (Ib) solid-solution region of the Bi2O3–WO3 system, were synthesized using the floating-zone furnace method. Synchrotron X-ray and neutron single-crystal diffraction data were used to confirm the previously tentative assignment of the room-temperature space group as I41. Fourier analysis of the combined X-ray and neutron datasets was used to elucidate and refine fully the cation and anion arrays for the first time. The mixed cation site M1 is shown to be coordinated by eight O atoms in an irregular cube when M = Bi, and by six O atoms in an octahedron when M = W. The resulting disorder in the average structure around M1 is discussed in the context of experimentally observed oxide-ion conductivity.
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Eid, Dalia F., Angela Gomez-Simmonds, Vitaliya Boyar, Anne-Catrin Uhlemann y Lorry G. Rubin. "1164. Acquisition of Methicillin-Susceptible Staphylococcus aureus in the Neonatal Intensive Care Unit: Molecular Comparison of Relatedness of Isolates". Open Forum Infectious Diseases 8, Supplement_1 (1 de noviembre de 2021): S673—S674. http://dx.doi.org/10.1093/ofid/ofab466.1357.
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Abstract Background In the NICU MSSA infections occur frequently and cause morbidity and mortality. Colonization is a risk factor for infection. Optimal infection prevention strategies await a more complete understanding of acquisition and transmission. To investigate possible transmission, we studied whether newly MSSA colonized infants share a strain with another contemporaneously colonized infant. Methods This is a prospective observational study in a level IV NICU from April through November 2019. Infants had weekly MSSA nasal surveillance cultures. Isolates from newly MSSA colonized infants and other infants colonized with MSSA during the same/previous week were subjected to staphylococcal protein A (spa) typing; most pairs with a concordant (CC) spa type were analyzed by whole genome sequencing (WGS; Illumina MiSeq). Pairs of isolates with a CC spa type and < 25 single nucleotide polymorphism differences on WGS were considered closely related (CC pairs). A control group consisted of pairs of isolates from a newly colonized infant with one randomly chosen colonized infant with a discordant (DC) spa type during the same/previous week. The medical records were reviewed for staff member (SM) and room assignment. Fischer’s exact test was used to compare proportions. Results Isolates from 60/68 consecutive newly MSSA colonized infants and 111/133 comparison infants were available for spa typing. Of these 60 infants, 23 (38 %) had a CC spa type with another infant colonized during the same/previous week. Of 18 isolate pairs from infants with a CC spa type that were subjected to WGS, 12 (67%) pairs of isolates were closely related. 7/12 (58 %) of CC pairs had a SM in common compared to 2/13 (15 %) in the DC pair groups, p=0.04. 2/12 (17 %) of CC pairs shared a room compared to 2/13 (15 %) pairs in the DC group, p=1.0. Conclusion Among newly MSSA colonized infants at least 25% are colonized with an isolate closely related to that of another colonized infant indicating likely infant to infant transmission. WGS is more discriminatory than spa typing for MSSA. Given the lack of commonality of room assignment and the commonality of SM assignment, a possible role of healthcare personnel in MSSA transmission should be further investigated. Disclosures Anne-Catrin Uhlemann, MD, PhD, Merck (Grant/Research Support)
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Streltsov, Victor A., Philip N. H. Nakashima, Alexandre N. Sobolev y Ruslan P. Ozerov. "Crystal structure study of a β′-copper vanadium bronze, Cu x V2O5 (x = 0.63), by X-ray and convergent beam electron diffraction". Acta Crystallographica Section B Structural Science 61, n.º 1 (19 de enero de 2005): 17–24. http://dx.doi.org/10.1107/s0108768104027739.
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The single-crystal structure of a β′-copper vanadium bronze, Cu0.63V2O5, has been studied at room temperature and 9.6 K, and compared with that of the β-sodium vanadium bronze, Na0.33V2O5, structure. No convincing evidence to oppose an assignment of centrosymmetric C2/m symmetry to the structure was identified using the X-ray data. A subsequent convergent beam electron diffraction (CBED) experiment was performed and confirmed the C2/m space group. The oxygen–vanadium atom framework of Cu0.63V2O5 is close to that of Na0.33V2O5. However, in the copper compound the Cu atoms are located in two positions: Cu1 in the 4(i) position with x = 0.541, y = 0 and z = 0.345, and Cu2 in the 8(j) position with x = 0.529, y = 0.038 and z = 0.357. The crystal structure changes little with temperature. Disorder of the Cu ion over two sites is seen at 9.6 K. This suggests that distribution of the Cu atoms over two sites is of a more static than dynamic nature.
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Zhu, Yikun y Zhiling Du. "Research on the Key Technologies of Network Security-Oriented Situation Prediction". Scientific Programming 2021 (31 de mayo de 2021): 1–10. http://dx.doi.org/10.1155/2021/5527746.
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In today’s increasingly severe network security situation, network security situational awareness provides a more comprehensive and feasible new idea for the inadequacy of various single solutions and is currently a research hotspot in the field of network security. At present, there are still gaps or room for improvement in network security situational awareness in terms of model scheme improvement, comprehensive and integrated consideration, algorithm design optimization, etc. A lot of scientific research investments and results are still needed to improve the form of network security in a long and solid way. In this paper, we propose a network security posture assessment model based on time-varying evidence theory for the existing multisource information fusion technology that lacks consideration of the problem of threat occurrence support rate over time and make the threat information reflect the law of time change by introducing a time parameter in the basic probability assignment value. Thus, the existing hierarchical threat posture quantitative assessment technique is improved and a hierarchical multisource network security threat posture assessment model based on time-varying evidence theory is proposed. Finally, the superiority of the proposed model is verified through experiments.
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Dadhania, D. A., G. D. Jadav, S. K. Chavda y J. A. Bhalodia. "Structural and Transport Properties of La<sub>0.85</sub>Te<sub>0.15</sub>MnO<sub>3</sub> Manganite and its Composite with Al<sub>2</sub>O<sub>3</sub>". Materials Science Forum 1048 (4 de enero de 2022): 110–20. http://dx.doi.org/10.4028/www.scientific.net/msf.1048.110.
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The manganite systems investigated during the present work are pure La0.85Te0.15MnO3 (LTMO) and its composite with 12% concentration of Al2O3 nano powder (LTMO + Al2O3). The materials were prepared by the modified auto combustion technique. The samples were characterized by X-ray diffraction. The powder X-ray diffraction pattern of pure LTMO at room temperature shows that sample is in single phase with no detectable secondary phases and the sample have a rhombohedral structure in hexagonal with the space group R3c. The XRD pattern of LTMO + 12% Al2O3 indicates the clear presence of Al2O3 nano phase in the composite. In the present study, the FTIR Spectroscopy of both samples was carried out. It is clear from the Vibrational assignment for the value of corresponding peak position of FTIR spectra that no extra unwanted impurity is present in samples. A quantitative analysis of the energy dispersive spectroscopy (EDS) data indicates that the observed concentration of elements are very close to the calculated values from its chemical formula. R-T measurements reveals that the addition of secondary phase in manganite strongly influenced on electronic and magnetoresistance behaviour. We summarise some of the salient features of the results.
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Chua, Michael E., Megan A. Saunders, Paul R. Bowlin, Jessica M. Ming, Roberto Iglesias Lopes, Walid A. Farhat y Joana Dos Santos. "Impact of smartphone digital photography, email, and media communication on emergency room visits post-hypospadias repair". Canadian Urological Association Journal 11, n.º 3-4 (11 de abril de 2017): 134. http://dx.doi.org/10.5489/cuaj.4170.
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Introduction: Advances in communication technology are shaping our medical practice. To date, there is no clear evidence that this mode of communication will have any effect on unnecessary postoperativeemergency room (ER) visits. We aim to evaluate the effect of email and media communication with application of smartphone digital photography on post-hypospadias repair ER visit rates.Methods: This prospective cohort study included all patients who underwent hypospadias repair performed by a single surgeon from October 2014 to November 2015. Patients were categorized intotwo groups: Group A consented for smartphone photography and email communication and Group B declined. Reason for ER visits within 30 days postoperatively was assessed by another physician, who was blinded of patient group assignment. The reasons were categorized as: unnecessary ER visit, indicated ER visit, or visit unrelated to hypospadias surgery. Chi-square test and T-test were used for statistical analysis. Relative risk (RR) and corresponding 95% confidence interval (CI) were also calculated. Statistical significance was set at p<0.05.Results: Over a 14-month period, 96 patients underwent hypospadias repair (81 in Group A, 15 in Group B 5). No significant difference was noted between groups for overall ER return rate (RR 0.46, 95% CI 0.21, 1.0). However, the number of ER visits for wound check not requiring intervention was significantly lower in Group A than in Group B (RR 0.14, 95% CI 0.035, 0.56); likewise, a higher number of ER visits requiring intervention was noted in Group A compared with Group B, although statistically this was not significant (RR 1.67, 95% CI 0.23, 12.21).Conclusions: Email communication with the use of smartphone digital photography significantly reduced the number of unnecessary ER visits for post-hypospadias wound checks.
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Myland, Paul, Sebastian Babilon y Tran Quoc Khanh. "Tackling Heterogeneous Color Registration: Binning Color Sensors". Sensors 21, n.º 9 (22 de abril de 2021): 2950. http://dx.doi.org/10.3390/s21092950.
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Intelligent systems for interior lighting strive to balance economical, ecological, and health-related needs. For this purpose, they rely on sensors to assess and respond to the current room conditions. With an augmented demand for more dedicated control, the number of sensors used in parallel increases considerably. In this context, the present work focuses on optical sensors with three spectral channels used to capture color-related information of the illumination conditions such as their chromaticities and correlated color temperatures. One major drawback of these devices, in particular with regard to intelligent lighting control, is that even same-type color sensors show production related differences in their color registration. Standard methods for color correction are either impractical for large-scale production or they result in large colorimetric errors. Therefore, this article shows the feasibility of a novel sensor binning approach using the sensor responses to a single white light source for cluster assignment. A cluster specific color correction is shown to significantly reduce the registered color differences for a selection of test stimuli to values in the range of 0.003–0.008 Δu′v′, which enables the wide use of such sensors in practice and, at the same time, requires minimal additional effort in sensor commissioning.
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Bowmaker, Graham A., Robert D. Hart, Brian W. Skelton y Allan H. White. "Syntheses, Structures and Vibrational Spectroscopy of Some Mixed Pyridine/Triphenylphosphine Adducts of Copper(I) Cyanide". Zeitschrift für Naturforschung B 59, n.º 11-12 (1 de diciembre de 2004): 1293–300. http://dx.doi.org/10.1515/znb-2004-11-1247.
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Abstract Single crystal room temperature X-ray structure determinations are described for three adducts formed between copper(I) cyanide, pyridine (‘py’) and triphenylphosphine of (p : q : r =) 1:1:1, 1:1.5:0.5 and 1:0.5:2 (plus py hemisolvate) stoichiometry. The latter is binuclear [(Ph3P)2(py)Cu(μ- CN)Cu(PPh3)2(CN)]. py; the others are linear polymers with . . .Cu(μ-NC)Cu(μ-NC)Cu. . . spines with four-coordinate copper atoms, the coordination sphere of every copper atom in the first being completed by pendant py and Ph3P ligands, while the second has those of alternate copper atoms coordinated by a pair of py ligands. Assignment of bridging CN in all cases is crystallographically ambiguous. The IR spectra of the infinite polymeric complexes show bands that are assigned to vibrations of the CuCN chains in the complexes: ν(CN), ν(CuC/N) (the CuC/N stretching mode, involving vibration of the CN group between its two neighbouring Cu atoms), δ (CuCN) (the restricted rotation of the CN group) and δ (NCuC) (the counter vibration of the Cu substructure against the CN substructure). The ν(CN) and ν(CuC/N) frequencies show correlations with the Cu-C/N bond lengths that are similar in form to those recently established for a range of AgCN complexes.
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Bowmaker, GA, JV Hanna, RD Hart, PC Healy y AH White. "Structural and Spectroscopic Studies on the Dimeric Complexes of Tris(2-methylphenyl)phosphine With Copper(I) Halides". Australian Journal of Chemistry 47, n.º 1 (1994): 25. http://dx.doi.org/10.1071/ch9940025.
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1:1 adducts of the copper(I) halides, CuX (X = Cl, Br, I), with the sterically hindered ligand tris (2-methylphenyl) phospine [P(o- tol )3] have been synthesized as crystalline dihalo -bridged centrosymmetric binuclear species; six compounds have been characterized by solid-state CP-MAS n.m.r. and far-infrared spectroscopy and by room-temperature single-crystal X-ray structure determination. For X = Cl , the dimeric complex. [P(o- tol )3CuCl]2, with three-coordinate copper atoms has been obtained from acetonitrile solution. Similar dimeric complexes for X = Br and I were obtained from toluene solution, the iodide adduct incorporating cocrystallized toluene. The X = Br and I complexes crystallized from acetonitrile solution yield mixed- ligand four-coordinate copper(I) dimers, [( MeCN )P(o- tol )3CuX]2, the iodide as a 2MeCN solvate. An additional crystalline phase incorporating crystallographically independent molecules of both the three-coordinate dimer and the four-coordinate mixed- ligand dimer has also been characterized for X = Br. Solid-state 31P CP-MAS n.m.r. spectra of the complexes at B = 7.05 T show well resolved asymmetric quartets with a ∆v3/∆v1 of 1.4 for the PcuX2 complexes and 1.1-1.2 for the PcuX2N complexes; these results reflect the geometric and bonding changes in the copper coordination sphere. Far-infrared spectra of the complexes show two strong halogen-sensitive bands, with a wavenumber separation of 30-40 cm-1, which have been assigned to copper-halogen stretching modes v( CuX ), this assignment being supported by a normal coordinate analysis on the Cu2X2 core.
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Jain, Mahendra K., Anubhuti Jain y Devendra Sareen. "Intrapartum oropharyngeal and nasopharyngeal suctioning in neonates born through meconium-stained amniotic fluid: Indian scenario". International Journal of Contemporary Pediatrics 5, n.º 6 (22 de octubre de 2018): 2103. http://dx.doi.org/10.18203/2349-3291.ijcp20183841.
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Background: Meconium aspiration syndrome (MAS) is a life-threatening respiratory disorder in infants born through meconium-stained amniotic fluid (MSAF). Although anecdotal data concerning the efficacy of intrapartum oropharyngeal and nasopharyngeal suctioning of MSAF are conflicting, the procedure is widely used. We aimed to assess the effectiveness of intrapartum suctioning for the prevention of MAS.Methods: A prospective quasi randomized control trial, assessor blind, single centre study was done at Department of neonatology, Geetanjali Medical College and Hospital, Udaipur, Rajasthan. Patients were enrolled over a total period of 16 months started from January 2016 to April 2017. 312 patients with MSAF of any consistency, gestational age at least 37 weeks, and cephalic presentation were randomly assigned to suctioning of the oropharynx and nasopharynx (including the hypopharynx) before delivery of the shoulders (n=127), or no suctioning before delivery (n=185). Postnatal delivery-room management followed Neonatal Resuscitation Program guidelines. The primary outcome was incidence of MAS. Clinicians diagnosing the syndrome and designating other study outcomes were masked to group assignment. An informed consent waiver was used.Results: No significant difference between treatment groups was seen in the incidence of MAS [36 (26.7%) suction versus 36 (19.5%) no suction; p = 0.167], mortality in suction [5 (3.91%) versus no suction 5 (2.74%); p = 0.779], or in the duration of ventilation, oxygen treatment, and hospital care. There was statistically significant difference in need for mechanical ventilation for MAS [13 (10.23%) vs 4 (2.2%); p = 0.005], any respiratory support for MAS 25 (19.7%) suction versus 18 (9.7) p = 0.019).Conclusions: Routine intrapartum suctioning of infants born through MSAF does not reduce the incidence of MAS. On the contrary, intrapartum suctioning might result in complications like more infant required neonatal resuscitation and respiratory support.
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Bowmaker, Graham A., Jack M. Harrowfield, Peter C. Junk, Brian W. Skelton y Allan H. White. "Syntheses, Structures and Vibrational Spectra of Some Dimethyl Sulfoxide Solvates of Bismuth(III) Bromide and Iodide". Australian Journal of Chemistry 51, n.º 4 (1998): 285. http://dx.doi.org/10.1071/c97035.
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Room-temperature single-crystal X-ray studies are recorded for some dimethyl sulfoxide (dmso) solvates of bismuth(III) bromide and iodide. Colourless BiBr3.3dmso is triclinic, P-1, a 8·467(4), b 9·109(4), c 13·901(4) Å, α 76·34(4), β 76·95(4), γ 64·56(4)°, Z = 2; conventional R on |F| was 0·050 for No 2306 independent ‘observed’ (I > 3σ(I)) reflections. The complex is mononuclear with a quasi-octahedral fac-bismuth environment, [(dmso-O)3BiBr3], isomorphous with the previously determined chloride. Orange BiI3-2dmso is triclinic, P-1, a 12·558(2), b 8·962(2), c 8·342(1) Å, α 61·85(1), β 78·27(1), γ 76·89(2)°, Z = 2 f.u., R 0·048 for No 1953. The complex is binuclear, a pair of iodide atoms bridging the two bismuth atoms, [(dmso-O)2I2Bi(µ-I)2BiI2(O-dmso)2]; the two O-dmso ligands about each six-coordinate bismuth lie trans. Red BiI3.2 ⅔ dmso is triclinic, P-1, a 16·435(6), b 14·926(2), c 12·396(3) Å, α 74·89(2), β 73·24(2), γ 79·18(2)°, Z = 6, R 0·059 for No 5858. The complex is [Bi(O-dmso)8] [Bi2I9], the eight-coordinate metal environment of the cation being, unusually, dodecahedral; in the anion a pair of quasi-octahedral six-coordinate bismuth atoms are bridged by three iodides, [I3Bi(µ-I)3BiI3]3-. Bands in the far-infrared and Raman spectra due to the v(BiX) modes are assigned and discussed in relation to the structures of the complexes. The assignment of the v(BiO) modes is discussed.
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Bowmaker, Graham A., Dip Singh Gill, Brian W. Skelton, Neil Somers y Allan H. White. "Syntheses, Structures and Vibrational Spectroscopy Studies of Copper(I) Perchlorate : Benzonitrile Adducts (1 : n) of n = 2, 3, 4, 5 Stoichiometry". Zeitschrift für Naturforschung B 59, n.º 11-12 (1 de diciembre de 2004): 1307–13. http://dx.doi.org/10.1515/znb-2004-11-1249.
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Abstract Syntheses and room-temperature single crystal X-ray structure determinations are recorded for an array of complexes formed between copper(I) perchlorate and benzonitrile of CuClO4 : PhCN (1:n) stoichiometry. Copper(I) perchlorate crystallized from neat benzonitrile solution yields a 1:5 CuClO4 : PhCN adduct, shown by the X-ray study to be of the form [Cu(NCPh)4](ClO4). PhCN, and, on recrystallization from dichloromethane, the 1:4 adduct, shown to be [Cu(NCPh)4](ClO4), the copper(I) atom in both the n = 4,5 adducts being in a quasi-tetrahedral four-coordinate environment, < Cu−N > 1.99 Å . Heating of either of the above materials under vacuum to 70 - 80◦ or 85 - 90 ◦C (Care!) yields 1:3 and 1:2 adducts respectively which may be crystallized from dichloromethane. The 1:3 adduct is shown to be of the form [(PhCN)3Cu(OClO3)], the CuN3 array quasi-trigonal planar (Σ N-Cu-N 358.0 ◦; Cu-N 1.906(4)-1.958(4), <> 1.93 Å ), with a long unidentate perchlorate oxygen approach (Cu. . .O 2.404(4) Å). The 1:2 adduct comprises a pair of quasi-linear [(PhCN)Cu(NCPh)] moieties (Cu-N 1.884(6), 1.866(5) Å ; N-Cu-N 158.6(3)◦] linked about an inversion centre by a pair of oxygen atoms from centrosymmetrically related perchlorate groups, so that a weakly bound fourmembered Cu(μ-O)2Cu central ring is obtained (Cu. . .O 2.445(4), 2.502(6) Å ). The structural data provide a basis for a comprehensive vibrational spectroscopic study across the whole array. These spectra show features that can be attributed to the structural changes that are observed with the change in the number of benzonitrile molecules in the compounds. The vibrational spectra of the acetonitrile complex [Cu(NCMe)4](ClO4) have also been recorded and used to assist in the assignment of the spectra of the various stoichiometries of the benzonitrile compounds.
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White, B. A. "Robust polynomial eigenstructure assignment using dynamic feedback controllers". Proceedings of the Institution of Mechanical Engineers, Part I: Journal of Systems and Control Engineering 211, n.º 1 (1 de febrero de 1997): 35–51. http://dx.doi.org/10.1243/0959651971539678.
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This paper presents a dynamic controller format for use in polynomial eigenstructure assignment. It formulates the controller in singular-value decomposition format, which enables the designer to use simple SISO (single-input, single-output) compensators, together with direction matrices to construct the controller. The technique utilizes the root locus to evaluate stability and performance. It also introduces several metrics for decoupling, disturbance rejection, actuator movement and stability robustness in a graphical manner that allows a systematic design to be carried out. The paper also includes a two-input, two-output design example to illustrate the technique.
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Liu, Qingtao, Jie Xu, Qiqing Wang y Wenping Li. "Risk Assessment of Water Inrush from Coal Seam Roof Based on the Combined Weighting of the Geographic Information System and Game Theory: A Case Study of Dananhu Coal Mine No. 7, China". Water 16, n.º 5 (28 de febrero de 2024): 710. http://dx.doi.org/10.3390/w16050710.
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Coal mines’ water inrush is one of the five major disasters that affect the safety of coal mine production. The assessment of coal mines’ water inrush is a prerequisite for preventing and controlling coal mines’ water inrush. To objectively and effectively evaluate the risk of water inrush in the coal seam roof and overcome the shortage of single assignment methods, two methods, the analytic hierarchy process and the entropy method, are used in this paper to determine each evaluation factor’s subjective and objective consequences. Game theory is applied to obtain the combined weights of each influencing factor to make up for the lack of a single assignment method. Taking the roof of Coal Seam No. 7 in mining Areas I and II of Dananhu Coal Mine No. 7 as an example, six primary evaluation indexes are created to control water inrush in the coal seam roof. The comprehensive weights of each index is determined; a vulnerability index evaluation model is established; and the results of the water inrush risk zone in the coal seam roof of Dananhu Coal Mine No. 7 are obtained using the GIS spatial analysis function. The results show that the discriminatory effects of the zoning model have a high accuracy and can provide a reference basis for future coal seam mining control work in this mine.
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Pongchairerks, Pisut. "A Probabilistic Hill-Climbing Algorithm for the Single-Source Transportation Problem". Sustainability 15, n.º 5 (28 de febrero de 2023): 4289. http://dx.doi.org/10.3390/su15054289.
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This paper proposes a probabilistic hill-climbing algorithm, called PH, for the single-source transportation problem (STP). PH is a tree search algorithm in which each node contains an assignment problem (AP) transformed from the STP being solved. The transformation converts each source’s product units into product lots; a product lot equals multiple product units. The AP aims to find the optimal assignment of product lots to destinations to minimize the total assignment cost. PH uses the Hungarian method to find the optimal solution of the AP in every node, which is a solution of the STP. For the AP of the root node (as the initial current node), the number of each source’s product lots is set to be small enough to guarantee the generation of a feasible solution for the STP. To generate every subsequent level, the current node is branched into multiple child nodes, in which the number of child nodes equals the number of sources in the STP. The AP of each child node is modified from the AP of the current node by adding one more product lot into a specific different source. Consequently, each child node provides a solution that is better than or the same as the current node’s solution; however, some child nodes’ solutions may be infeasible for the STP due to the insufficiency of a source’s capacity. If all of the child nodes cannot find a better feasible solution than the current node’s solution, PH stops its procedure. To diversify the search, PH selects one of the child nodes as the new current node in a probabilistic way, instead of always selecting the best child node. The experiment’s results in this paper reveal the performance of the three variants of PH.
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Kowollik, Wolfgang y Wolfgang Voelter. "Notizen: Synthese und NMR-spektroskopische Eigenschaften von Benzyl-2,3-anhydro-4-desoxy-4-[N]-pyridinium-pyranosiden/Synthesis and NMR Spectroscopic Properties of Several Benzyl 2,3-Anhydro-4-deoxy-4-[N]-pyridinium Pyranosides". Zeitschrift für Naturforschung B 47, n.º 4 (1 de abril de 1992): 589–90. http://dx.doi.org/10.1515/znb-1992-0421.
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Benzyl 2,3-anhydro-4-0-triflyl-β-L-ribopyranoside (1) and benzyl 2,3-anhydro-4-O-triflyl-α-D-lyxopyranoside (3) react with pyridine to give benzyl 2,3-anhydro-4-deoxy-4-[N]-pyridinium - α-D-lyxopyranoside triflate (2) and benzyl 2,3-anhydro-4-deoxy-4-[N]-pyridinium -β-L-ribopyranoside triflate (4). Similar reactions with thiourea and dimethylsulfoxide are mentioned. Compound 2 is stable at room temperature, whereas compound 4 decomposes in a few hours (neighbouring group effect). The 13C NMR assignments of 2 are proved by 13C {1H} single frequency decoupling experiments.
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Witherspoon, Kelsey, Manisha Shah, Justin Smyer, Nora Colburn, Christina Liscynesky, Courtney Hebert y Shandra Day. "Transmission of COVID-19 on an Inpatient Hospital Prison Unit". Antimicrobial Stewardship & Healthcare Epidemiology 1, S1 (julio de 2021): s47. http://dx.doi.org/10.1017/ash.2021.87.
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Background: Prison populations have been disproportionally affected by COVID-19, partly due to challenges related to social distancing. Data on viral transmission dynamics in inpatient prison units remain limited. The Ohio State University Wexner Medical Center (OSUWMC) has a 24-bed inpatient prison unit in collaboration with the Ohio Department of Rehabilitations and Corrections (ODRC). The unit has 5 shared rooms holding 4 patients each and 4 single-patient rooms. Several cases of inpatient transmission of COVID-19 were identified on the inpatient prison unit. Methods: An IRB-approved retrospective chart review was conducted to evaluate inpatient transmission dynamics of hospital-acquired (HCA) COVID-19. All ODRC patients admitted from March 1 to April 24, 2020, were included. Patients assigned to the prison unit during their hospital stay were evaluated for potential HCA COVID-19, defined as a positive SARS-CoV-2 test ≥4 days after admission. Patient characteristics, testing data, symptoms, aerosol-generating procedures (AGPs), and room assignments were reviewed. Healthcare workers (HCWs) and correction officers (COs) working on the unit who tested positive during this period were identified. Results: In total, 142 ODRC patients were admitted during the study period and 89% had a positive SARS-CoV-2 testing prior to or during admission. Also, 61 patients (43%) were assigned to the prison unit. Moreover, 8 patients on the unit met potential HCA COVID-19 definition with 7 linked to 3 distinct clusters. Also, 7 COs had COVID-19 (outside hospital exposure) and 5 HCWs acquired COVID-19 from patient exposure on the unit. In cluster 1, 4 patients admitted to the same room developed HCA COVID-19. A symptomatic index patient not tested on admission given an atypical presentation required CPAP and frequent nebulizer treatments. In cluster 2, 1 patient from cluster 1 was transferred to another room. The new roommate subsequently developed HCA COVID-19. In cluster 3, a symptomatic correctional officer was assigned to 2 patients in a shared room; the patients later developed HCA COVID-19. Conclusions: Three patient clusters of HCA COVID-19 on a prison unit were identified. Aerosol transmission potentially played a role in cluster 1. Inpatient transmission within the unit prompted updated guidance for ODRC admissions, including universal SARS-CoV-2 admission testing, excluding patients requiring AGPs from shared rooms, and preemptive isolation for patients from an ODRC facility experiencing a COVID-19 surge. Universal testing was quickly expanded to all inpatient admissions. HCWs and COs were also linked to inpatient transmission, highlighting the importance of strict infection control practices for patient populations who cannot socially distance.Funding: NoDisclosures: None
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Oh, Kyung Hui, Joon Hyung Cho y Seung-Bin Kim. "Raman Spectra of 6LiRbSO4 and 7LiRbSO4". Applied Spectroscopy 47, n.º 7 (julio de 1993): 999–1006. http://dx.doi.org/10.1366/0003702934415408.
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The polarized Raman spectra of single-crystal 6LiRbSO4 and 7LiRbSO4 at room temperature are reported. On the basis of these data, symmetry-based band assignments are given for both internal and external optic modes. The translational optic modes of the lithium ion appear in the region between 444 and 364 cm−1. Vibrational coupling interactions are noted between the sulfate ion ν2 and the lithium translational optic modes in the same irreducible representation. Coupling interactions are negligible or small in 7LiRbSO4, while in 6LiRbSO4 the lithium isotope effect shifts the lithium translational modes into more coupling interaction with the sulfate ion ν2 modes.
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Uriarte, Eugenio, Fernanda Borges y Alexandra Gaspar. "Synthesis and structural elucidation of a series of isoflavones-based on FPR antagonists". International Journal of Bioorganic and Medicinal Chemistry 1, n.º 1 (25 de febrero de 2021): 10–16. http://dx.doi.org/10.55124/bmc.v1i1.22.
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Isoflavones are naturally occurring compounds well-known for their beneficial role in several diseases, such as cancer and inflammation. Recently some isoflavones derivatives were reported as potent and competitive antagonists of formyl peptide receptors (FPRs) with an important role in regulating the inflammatory process. As a result of their biological activities, there is a huge interest in developing synthetic procedures to obtain isoflavones. Surprisingly, and as far as our knowledge goes, the synthetic work and full characterisation of the isoflavones described as FPR antagonists weren’t yet reported. The work herein described comprises the synthesis of two series of 2-trifluoromethyl isoflavones, including the ones described as FPR antagonists and their complete characterisation by 1D, 2D NMR techniques and high-resolution mass spectroscopy.
IntroductionIsoflavones are naturally occurring compounds mainly found in soybeans, soy foods and vegetables. Chemically, they retain the typical C6C3C6 skeleton of flavonoids, consisting of two aromatic rings being linked through an oxygenated heterocycle nucleus, being isomers of flavones. They are characterised by the presence of a double bond between carbons C2 and C3 and an aromatic ring in the C3 position.1
Dietary isoflavones are well-known by their ability to act as phytoestrogens.1,2 Nevertheless, other health benefits have been attributed to this class of compounds namely, their beneficial role in cancer, such as hormone-dependent cancers, in osteoporosis, cardiovascular disease and inflammation, and several mechanisms have since been proposed to explain these activities.3 Interestingly,a series of synthetic isoflavones were recently reported as potent and competitive antagonists of formyl peptide receptors (FPRs) having an important role in the regulation of inflammatory reactions implicated in disease pathogenesis.4 Thus, the isoflavone backbone represents a promising scaffold for the development of novel FPR antagonists.
As a result of their biological activity, there is a huge interest in the development of synthetic procedures to obtain isoflavones and their derivatives for structure-activity relationship studies. Surprisingly, and as far as our knowledge goes, the synthetic work and full characterisation of the synthetic isoflavones described as FPR antagonists(compounds A1, B2 and B3, figure 1), weren’t yet reported.
Accordingly, the work herein described comprises the synthesis of two series of 2-trifluoromethyl isoflavones (figure 1), including the ones described as FPR antagonists and their complete characterisation by 1D and 2D NMR techniques and by high-resolution mass spectroscopy.
ExperimentalMaterialsAll reagents were purchased from Sigma-Aldrich Química, S.L. and Alfa Aesar, Thermo Fisher Scientific. All solvents were pro analysis grade from Merck, Carlo Erba Reagents and Scharlab. Thin layer chromatography (TLC) was performed on pre-coated silica gel 60 F254 acquired from Merck with layer thickness of 0.2 mm. The spots were visualized under UV detection at 254 and 366 nm. Column chromatography was carried out with silica gel 60 0.040-0.063 mm acquired from Carlo-ErbaReactifs. Solvents were evaporated with a BuchiRotavapor.
NMR spectroscopy
1H and 13C NMR data were acquired on a Bruker Avance III 400 NMR spectrometer operating at 400.15 MHz and 100.62 MHz, respectively. For the 1H NMR experiments, the relaxation delay was 90° pulse, spectral width of 8012 Hz and 65 K data points. In the case of the 13C NMR experiments, the corresponding parameters were 30º pulse, 24038 Hz and 65 K, respectively, and 2.0 s relaxation delay. For the Distortionless Enhancement by Polarization Transfer (DEPT) sequence, the width of the 90º pulse for 13C was 7.7 μs, and the 90º pulse for 1H was 9.8 μs; the delay 2JC, H was set to 2.0 ms. For correlation spectroscopy (COSY) and heteronuclear single quantum coherence (HSQC), the data points were set to 2 K × 256 (t2 × t1) with a relaxation delay D1 of 1.5 s. The Heteronuclear Multiple Bond Connectivity (HMBC) was acquired with data points set to 4 K × 256 (t2 × t1) and relaxation delay D1 of 1 s. Furthermore, the long-range coupling time for HMBC was set to 71 ms.The data were processed using quadratic sine-bell weighting functions in both dimensions.
1H and 13C spectra of the samples were recorded at room temperature in 5 mm outer-diameter tubes. Samples were prepared in deuterated chloroform (CDCl3). Tetramethylsilane (TMS) was used as internal reference; chemical shifts (δ) were expressed in parts per million (ppm), and coupling constants (J) were given in Hertz (Hz). The 1H and 13C chemical shifts of CDCl3 were 7.26 and 77.2 ppm, respectively.
Mass spectroscopyMass spectra (MS) were carried out on a Bruker Microtof (ESI) apparatus; the data were reported as m/z (% of the relative intensity of the most important fragments).
Synthesis of trifluoromethylisoflavones esters Compounds A1-A3 (Figure 1) were obtained by the cyclization of the 2-(2′-Chlorophenyl)-2′,4′-dihydroxyacetophenone, followed by its acylation with the corresponding acyl chloride, as depicted in scheme 1 (step b and c).5,6,7 Briefly, 2-(2′-Chlorophenyl)-2′,4′-dihydroxyacetophenone (1mmol) was cyclised, using trifluoroacetic anhydride (3mmol) and triethylamine (2mL). The reaction was refluxed for one hour, then poured into water, acidified (pH=3) and stirred at room temperature for another hour. The crude material was extracted with ethyl acetate (3x 10 mL). were dried over anhydrous sodium sulphate and the solvent evaporated. 7-hydroxy-3-(2-chlorophenyl)-2-(trifluoromethyl)-4H-chromen-4-one was recrystallised from ethyl acetate and obtained in a 65% yield. The acylation step was performed following the methodology described by Jayashree et al. 7: 7-hydroxy-3-(2-chlorophenyl)-2-(trifluoromethyl)-4H-chromen-4-one and (1mmol) and the corresponding acyl chloride (1.25 mmol), were dissolved in pyridine (7.5mL), and the solution refluxed for one hour (scheme 1, step c). The mixture was then cooled to room temperature and poured into water (30 mL), acidified to pH=5, and stirred at room temperature for two hours. Afterwards, the mixture was extracted with ethyl acetate (3x 10mL). The combined organic phases were dried over anhydrous sodium sulphate and the solvent evaporated under reduced pressure.
The structure, chemical name, yield, and mass spectroscopy data of synthesised compounds are depicted in table I.
Compounds B1-B3 (Figure 1) were obtained by the acylation of 7-hydroxy-3-(2-methoxyphenyl)-2-(trifluoromethyl)-4H-chromen-4-one with the corresponding acyl chloride, following the methodology described above and depicted in scheme 1 (step c). 7-hydroxy-3-(2-methoxyphenyl)-2-(trifluoromethyl)-4H-chromen-4-one was obtained following the procedure described in literature 8 (scheme 1, step a and b).
Results and DiscussionThe complete structural characterisationof all synthesisedcompounds (A1- A3 and B1- B3) is depicted in tables II and III. The unambiguous assignment of all carbons and hydrogens was achieved by the combined expenditure of one- and two-dimensional nuclear resonance techniques.
The unequivocal assignment of the NMR data for compound A1 was performed as followed:
The hydrogens H-5 and H-8 of the benzopyran structure of compound A1 were readily assigned considering their splitting pattern and coupling constants (Table II). Thus, the peak at δ=8.31 ppm (d, J=8.8 Hz) was assigned to H-5 and the peak at δ=7.60 ppm (d, J=2.1 Hz) to H-8. The COSY experiment revealed an H-H interaction between these two peaks and the multiplet at δ=7.43-7.33 ppm (Figure 2), which integrated for three hydrogens. Furthermore, for this multiplet, an H-H interaction was observed with a peak at 7.52 ppm (ddd, J=0.4, 1.4, 7.9 Hz) (Figure 2). The construction of a splitting three diagram for the signal at δ=7.43-7.33 ppm enabled the identification of three hydrogens: one hydrogen at δ=7.41 ppm (H-4’, ddd, J=1.7, 7.5, 7.9 Hz), other at δ=7.39 ppm (H-6, dd, J=2.1, 8.8 Hz) and another at δ=7.35 ppm (H-5’, ddd, J=1.4, 7.4, 7.5 Hz).
The COSY experiment also showed an H-H interaction between two double doublets (at δ=8.05 ppm and 7.75 ppm) with the multiplet at δ= 7.24-7.21 ppm (which integrates for two hydrogens) (Figure 2). The splitting pattern along with the coupling constants enabled the attribution of the peak at δ=8.05 ppm to H-6’’, and the peak at δ=7.75 ppm to H-4’’. Moreover, by assembling a tree diagram of the multiplet at δ= 7.24-7.21 ppm, H-5’’ and H6’ were assigned to δ=7.23 ppm. Both hydrogens showed a double doublet multiplicity. However, H6’’ showed characteristic coupling constants of a thiophene ring (J=3.8, 5.0 Hz) while H6’ presented the typical meta and orthoconstants of a phenyl ring (J=1.7, 7.4 Hz).
The carbons of compound A1 were assigned using HSQC experiment and depicted in table II. The CF3 and the C-2 quaternary carbons were easily identified due to their typical coupling constants; the peak at δ= 118.9 ppm (d, J=277 Hz) was attributed to CF3, and the signal at δ= 149.4 ppm (d, J=37 Hz) was assigned as C-2. The other quaternary carbons were then assigned based on the HMBC experiment and chemical shifts with the long-range interactions summarized in Figure 3. The attribution of the quaternary carbons from the benzopyran nucleus (C-4, C-4a, C-8a, C-7) was as follows: a)The peak at δ= 175.1 ppm was assigned to C-4 due to their chemical shift and a long-range interaction with H-5; b) the long-range interaction detected between H-5 and H-8 with the peaks at δ=155.4 and 155.6 ppm allowed their attribution to C-7 and C-8a, respectively; c) a long-range interaction was detected between H-6 and the peak at δ=155.4 ppm, corroborating its assignment to C-7. Additionally, a long-range interaction of H-8 with the peak at δ=120.9 ppm was observed, which was identified as C-4a (Figure 4a).
The quaternary carbons of the exocyclic phenyl ring were attributed based on the long-range correlation between the H-3’, H-4’ and H-6’ and the quaternary carbon at δ= 134.3 ppm, which was assigned to C-2’ (Figure 4b). Furthermore, the HMBC experiment showed an interaction between H-6’ and a peak at δ= 123.7 ppm, which was thus assigned as C1’.
The signal at δ=159.4 ppm was assigned to carbon C-1’’ by its chemical shift and long-range interaction with H-4’’ and H-6’’. Moreover, H-4’’ and H-6’’ also showed a long-range interaction with the peak at δ=131.7 ppm, which was attributed to C-2’’ of the thiophene ring (Figure 4c). The structural assignment of compounds A2and A3 were based onthe attributions performed for compound A1.are depicted in table II.
Using the same approach, the unequivocal assignment of hydrogens and carbons of the C2’-methoxyl counterparts (compounds B1-B3), was accomplished and described in table III. Nevertheless, the hydrogens of the methoxyl group were readily assigned from 1H NMR spectrum, by their chemical shift, integration and multiplicity at δ=3.77 ppm, δ=3.76 ppm and δ=3.75 ppm for compounds B1, B2 and B3, respectively. It is also important to stress that the chemical shift of exocyclic aromatic hydrogens and carbons was slightly affected by theaffected by the presence of methoxyl group at position C-2’ instead of chlorine. All the hydrogens and carbons of compounds B1- B3, with exception off C-2’, that appear with higher values of chemical shifts, suffered an upfield chemical shift, while C-2’ appears at relative to their C2’-Cl counterparts (compounds A1- A3).
Table II: 1H and 13C NMR Data of Compounds A1-A3
Table I: 1H and 13C NMR Data of Compounds B1-B
ConclusionsThis work describes for the first time an effective synthetic strategy to obtain trifluoromethylisoflavones derivatives, namely the ones that were described as FPR antagonists.4Theisoflavones(compounds A1-A3 and B1-B3) were synthesised in good yields and had been fully characterised by homo- and hetero-nuclear NMR and high-resolution mass spectrometry. The acquired data allowed the unambiguous identification of these compounds, providing a valuable database for the unequivocal identification of other analogue libraries.
AcknowledgmentsThis work was funded by FEDER funds through the Operational Programme Competitiveness Factors-COMPETE and national funds by FCT – Foundation for Science and Technology under research grants (QUI/UI0081/2013, NORTE-01-0145-FEDER-000028 and PTDC/DTP-FTO/2433/2014). A. Gaspar (SFRH/BPD/93331/2013) grant is supported by FCT, POPH and QREN.
References
Szeja, W.; Grynkiewicz, G.; Rusin, A. “Isoflavones, their Glycosides and Glycoconjugates. Synthesis and Biological Activity”. Curr Org Chem. 2017, 21(3), 218-235.
Vitale, DC.; Piazza, C.; Melilli, B.; Drago, F.; Salomone, S. “Isoflavones: Estrogenic activity, biological effect and bioavailability”. Eur J Drug Metab Pharmacokinet. 2013, 38, 15–25.
Jie Yu, J.; Bi, XJ.; YU, B.; Chen, D. “Isoflavones: Anti-Inflammatory Benefit and Possible Caveats” 2016, 8(6), 361.
Schepetkin, IA.; Kirpotina, LN.; Khlebnikov, AI.; Cheng, N.; Ye, RD. “Antagonism of human formyl peptide receptor 1 (FPR1) by chromones and related isoflavones”. 2014, 92, 627–641.
Balasubramanian, S.; Nair, MG. “An Efficient “One Pot” Synthesis of Isoflavones”. Synth Commun. 2000, 30(3), 469-484.
Eiffe, E.; Heaton, A.; Walker, C.; Husband, A. “2-Substituted isoflavonoidcompounds, medicaments and uses”. 2009, WO 2009003229 A1.
Jayashree, BS.; Thejaswini, JC.; Nayak, Y.; Kumar, DV. “Synthesis of Novel Flavone Acyl Esters and Correlation of log P Value with Antioxidant and Antimicrobial Activity”. Chem Asian J. 2010, 22(2), 1055-1066.
John NicolsonLow, J. N.; Ligia R. Gomes, L.R.; Alexandra Gaspar, A.; Borges. “Structure of 7-hydroxy-3-(2-methoxyphenyl)-2-trifluoromethyl-4H-chromen-4-one”. Acta Crystallogr E Crystallogr Commun. 2017, 73, 1130–1134.
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Welsh, Allana K., Jeffrey O. Dawson, Gerald J. Gottfried y Dittmar Hahn. "Diversity of Frankia Populations in Root Nodules of Geographically Isolated Arizona Alder Trees in Central Arizona (United States)". Applied and Environmental Microbiology 75, n.º 21 (4 de septiembre de 2009): 6913–18. http://dx.doi.org/10.1128/aem.01103-09.
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ABSTRACT The diversity of uncultured Frankia populations in root nodules of Alnus oblongifolia trees geographically isolated on mountaintops of central Arizona was analyzed by comparative sequence analyses of nifH gene fragments. Sequences were retrieved from Frankia populations in nodules of four trees from each of three mountaintops (n = 162) and their levels of diversity compared using spatial genetic clustering methods and single-nucleotide or 1, 3, or 5% sequence divergence thresholds. With the single-nucleotide threshold level, 45 different sequences with significant differences between the mountaintops were retrieved, with the southern site partitioning in a separate population from the two other sites. Some of these sequences were identical in nodules from different mountaintops and to those of strains isolated from around the world. A high level of diversity that resulted in the assignment of 14 clusters of sequences was also found on the 1% divergence level. Single-nucleotide and 1% divergence levels thus demonstrate microdiversity of frankiae in root nodules of A. oblongifolia trees and suggest a partitioning of diversity by site. At the 3 and 5% divergence levels, however, diversity was reduced to three clusters or one cluster, respectively, with no differentiation by mountaintop. Only at the 5% threshold level do all Frankia strains previously assigned to one genomic group cluster together.
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Jeeva, P., D. Barathi, K. Prabakaran, M. Seenivasa Perumal, Ahmet Atac y Etem Kose. "Crystal Structure, Experimental and DFT of (Z)-4-((4-Fluorophenyl)amino)pent-3-en-2-one". Asian Journal of Chemistry 33, n.º 7 (2021): 1638–44. http://dx.doi.org/10.14233/ajchem.2021.23259.
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Single crystals of a organic compound, (Z)-4-((4-fluorophenyl)amino)pent-3-en-2-one (4FPA) were grown by the slow evaporation technique and characterized by X-ray diffraction and FT-IR spectra. The normal mode frequencies, intensities and the corresponding vibrational assignments were calculated using the GAUSSIAN 09W set of quantum chemistry codes at the DFT/B3LYP levels of theory using the 6-31+G(d,p) basis set. The Fourier transform infrared spectrum was obtained for the title molecule at room temperature. Reactivity features were determined based on global descriptors, electron density mapping and Fukui analysis to reveal the electrophilic and nucleophilic coordination of them. The thermodynamic and intramolecular interactions were also investigated. The non-covalent interaction mapped by reduced density gradient method reveals possible methyl (CH3) influence on the ring and NH groups with their reactivity and non-linear optical properties of 4FPA were found by first-order hyperpolarizability.
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Bettella, Francesco, Vincenzo D'Agostino y Lucia Bortolini. "Drainage flux simulation of green roofs under wet conditions". Journal of Agricultural Engineering 49, n.º 4 (19 de diciembre de 2018): 242–52. http://dx.doi.org/10.4081/jae.2018.838.
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The role of green roofs in reducing drainage fluxes is known, but despite extensive analysis in the literature, methods to predict the hydrologic performance for a given green roof composition are scarce. These methods are useful for the hydraulic design and for planning regulations that impose specific hydrological responses. This research investigates on the prediction of the drainage fluxes produced below a green roof with initial water content equal to its water retention capacity (worst-case scenario). Laboratory tests were performed to analyse the rainfall-drainage relationship for green-roof and single components (growing media and drainage storage layers) under specific rainfall intensities. Two types of largely used drainage/storage layers and growth media were analysed, both singularly and in combination. The experiments consider two rainfall events lasting 10 min with constant intensity. The results indicate that the Curve Number (CN) method (U.S. Soil Conservation Service) with a simple adaptation can be used to reproduce the green-roof hydrologic behaviour under antecedent moisture conditions comparable with those of the experiments. In fact, the water retention capacity, controlling the water-output initiation below the green roof, can be used as threshold variable of a step function, above which the CN method is applicable and below which drainage fluxes are practically null. Through this position, the CN assignment for a composite greenroof can be consistently estimated using the proprieties of the single components (drainage/storage layer and growing medium) and it provides values that are very close to those of waterproof media and quite higher than those suggested in companion researches. Drainage amounts are predicted with a standard error equal to 1.50 mm, which corresponds to 5.7% of the mean value observed. After rain initiation, the steady state condition of the drainage flux has proved to be markedly affected by the growing medium and drainage layer composing the system, which result effective in discriminating the green roof performance.
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Kumari, K. Swapna, Sangita Dixit, Mahendra Gaur, Dibyajyoti Uttameswar Behera, Suchanda Dey, Rajesh Kumar Sahoo, Patitapaban Dash y Enketeswara Subudhi. "Taxonomic Assignment-Based Genome Reconstruction from Apical Periodontal Metagenomes to Identify Antibiotic Resistance and Virulence Factors". Life 13, n.º 1 (9 de enero de 2023): 194. http://dx.doi.org/10.3390/life13010194.
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Primary apical periodontitis occurs due to various insults to the dental pulp including microbial infections, physical and iatrogenic trauma, whereas inadequate elimination of intraradicular infection during root canal treatment may lead to secondary apical periodontitis. We explored the complex intra-radicular microbial communities and their functional potential through genome reconstruction. We applied shotgun metagenomic sequencing, binning and functional profiling to identify the significant contributors to infection at the acute and chronic apical periodontal lesions. Our analysis revealed the five classified clusters representing Enterobacter, Enterococcus, Lacticaseibacillus, Pseudomonas, Streptococcus and one unclassified cluster of contigs at the genus level. Of them, the major contributors were Pseudomonas, with 90.61% abundance in acute conditions, whereas Enterobacter followed by Enterococcus with 69.88% and 15.42% abundance, respectively, in chronic conditions. Enterobacter actively participated in antibiotic target alteration following multidrug efflux-mediated resistance mechanisms, predominant in the chronic stage. The prediction of pathways involved in the destruction of the supportive tissues of the tooth in Enterobacter and Pseudomonas support their crucial role in the manifestation of respective disease conditions. This study provides information about the differential composition of the microbiome in chronic and acute apical periodontitis. It takes a step to interpret the role of a single pathogen, solely or predominantly, in establishing endodontic infection types through genome reconstruction following high throughput metagenomic DNA analysis. The resistome prediction sheds a new light on the therapeutic treatment guidelines for endodontists. However, it needs further conclusive research to support this outcome using a larger number of samples with similar etiological conditions, but different demographic origin.
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Bormann, Niels, Angeles Hernandez-Carrascal, Régis Borde, Hans-Joachim Lutz, Jason A. Otkin y Steve Wanzong. "Atmospheric Motion Vectors from Model Simulations. Part I: Methods and Characterization as Single-Level Estimates of Wind". Journal of Applied Meteorology and Climatology 53, n.º 1 (enero de 2014): 47–64. http://dx.doi.org/10.1175/jamc-d-12-0336.1.
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AbstractThe objective of this study is to improve the characterization of satellite-derived atmospheric motion vectors (AMVs) and their errors to guide developments in the use of AMVs in numerical weather prediction. AMVs tend to exhibit considerable systematic and random errors that arise in the derivation or the interpretation of AMVs as single-level point observations of wind. One difficulty in the study of AMV errors is the scarcity of collocated observations of clouds and wind. This study uses instead a simulation framework: geostationary imagery for Meteosat-8 is generated from a high-resolution simulation with the Weather Research and Forecasting regional model, and AMVs are derived from sequences of these images. The forecast model provides the “truth” with a sophisticated description of the atmosphere. The study considers infrared and water vapor AMVs from cloudy scenes. This is the first part of a two-part paper, and it introduces the framework and provides a first evaluation in terms of the brightness temperatures of the simulated images and the derived AMVs. The simulated AMVs show a considerable global bias in the height assignment (60–75 hPa) that is not observed in real AMVs. After removal of this bias, however, the statistics comparing the simulated AMVs with the true model wind show characteristics that are similar to statistics comparing real AMVs with short-range forecasts (speed bias and root-mean-square vector difference typically agree to within 1 m s−1). This result suggests that the error in the simulated AMVs is comparable to or larger than that in real AMVs. There is evidence for significant spatial, temporal, and vertical error correlations, with the scales for the spatial error correlations being consistent with estimates for real data.
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Dorst, Aletta G., Susana Valdez y Heather Bouman. "Machine translation in the multilingual classroom". Translation and Translanguaging in Multilingual Contexts 8, n.º 1 (6 de enero de 2022): 49–66. http://dx.doi.org/10.1075/ttmc.00080.dor.
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Abstract Machine Translation (MT), the process by which a computer engine such as Google Translate or Bing automatically translates a text from one language into another without any human involvement, is increasingly used in professional, institutional and everyday contexts for a wide range of purposes. While a growing number of studies has looked at professional translators and translation students, there is currently a lack of research on non-translator users and uses in multilingual contexts. This paper presents a survey examining how, when and why students at Leiden University’s Faculty of Humanities use MT. A questionnaire was used to determine which MT engines students use and for what purposes, and gauge their awareness of issues concerning privacy, academic integrity and plagiarism. The findings reveal a widespread adoption of Google Translate and indicate that students use MT predominantly to look up single words, as an alternative to a dictionary. Many seemed sceptical about the value of MT for educational purposes, and many assumed that the use of MT is not permitted by lecturers for graded assignments, especially in courses focusing on language skills. The results demonstrate a clear need for more MT literacy. Students may not need practical training in how to use MT, but there is much room for improvement in terms of when and why they use it.
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Faget, Marc, Juan M. Herrera, Peter Stamp, Ingrid Aulinger-Leipner, Emmanuel Frossard y Markus Liedgens. "The use of green fluorescent protein as a tool to identify roots in mixed plant stands". Functional Plant Biology 36, n.º 11 (2009): 930. http://dx.doi.org/10.1071/fp09125.
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Roots take up most of the resources required by a plant, but a lack of efficient research tools hinders our understanding of the function and relevance of the root system. This is especially evident when the research focus is not on a single plant, but on multiple plants that share the same soil resources. None of the available methods allow for simple, inexpensive, non-destructive, and objective assignment of observed roots in a mixture of plants to a target plant. Here, we demonstrate that transgenic plants expressing the green fluorescent protein (GFP), combined with the well established minirhizotron technique, is a route to overcoming this limitation. We planted transgenic maize (Zea mays L.) in combination with either its corresponding wild type, Italian ryegrass (Lolium multiflorum Lam.), or soybean (Glycine max (L.) Merr.). Identification of fluorescent roots allows the relative distribution of roots of each plant type and their interaction and interference with each other to be observed. The selected plants are suitable for model experiments to unravel fundamental belowground ecological processes. Because genetic transformation of plants is an established technique that can be applied to a large set of plant species, this method will be of interest to a broad range of research areas.
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IŞIK, Ahmet y Reyhan TEKİN SİTRAVA. "An Investigation of the Complexity of the Problems Posed by Prospective Teachers: The Case of Whole Number". Bartın University Journal of Faculty of Education 13, n.º 1 (17 de enero de 2024): 12–23. http://dx.doi.org/10.14686/buefad.1103194.
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The aim of this case study is to examine the linguistic and mathematical complexity of the problems that prospective primary school teachers posed related to four operations with whole numbers. A Problem Posing Questionnaire was administered to 64 participants and semi-structured interviews were conducted with 20 of 64 participants. The data was analyzed through frequency analysis and descriptive analysis. The findings of the study revealed that many prospective teachers posed problems based on the single-statement problem root, without any relation/condition. That is, the linguistic complexity of the problems written by the prospective teachers is in the lowest level which is regarded as assignment category, regardless of the complexity of the problem situation. Furthermore, if the problem situations do not contain any relationship, then many prospective teachers had preferred to pose one-step problems. On the other hand, when the information in the problem situation is related to each other, then they were able to pose multi-step problems which could be regarded as complex problems in terms of mathematically. It can be concluded that although the complexity of the problem situation given to the prospective teachers does not affect the linguistic complexity of the problems they pose; it affects the mathematical complexity.
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Millar, M. A. y M. Byrne. "Biogeographic origins and reproductive mode of naturalised populations of Acacia saligna". Australian Journal of Botany 60, n.º 5 (2012): 383. http://dx.doi.org/10.1071/bt12028.
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Acacia saligna (Labill.) H.L.Wendl. is a species complex with an extensive history of anthropogenic utilisation and distribution. The taxon is naturalised and invasive in many countries. Extensive morphological variation makes accurate taxonomic identification of populations difficult. We used population genetic analysis to determine the biogeographic origins of 12 naturalised populations sampled from throughout south-eastern South Australia and assess the mode of reproduction (seedling or root suckering) at sites with active recruitment. Ten naturalised populations were assigned to Eastern ‘saligna’, although some also showed a lesser degree of affinity with other entities. A single population was assigned to Western ‘saligna’, but showed some affinity with Eastern ‘saligna’, and one population assigned to subsp. ‘lindleyi’ showed some affinity with Northern ‘lindleyi’. These assignments suggest that although several genetic entities of A. saligna are represented in South Australia, the majority of germplasm has originated from native populations of Eastern ‘saligna’ located around Esperance on Western Australia’s southern coast. Genetic diversity is limited in naturalised A. saligna compared with that present in the native range, suggesting a restricted number of historical introductions. Reproduction is predominantly by seedling recruitment, as opposed to clonal reproduction.
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Pradhan, Ninad, Dinesh Patlolla y Rupy Sawhney. "Scheduling and route optimisation for labour cost reduction in facility custodial maintenance". Journal of Facilities Management 15, n.º 2 (15 de mayo de 2017): 190–206. http://dx.doi.org/10.1108/jfm-11-2016-0048.
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Purpose The purpose of this paper is to present an optimised scheduling system for facility mangers and custodians. Experience-driven systems currently in use can result in poor ratings for facility maintenance metrics such as overtime hours, utilisation difference and labour costs. Design/methodology/approach The cleaning schedule and custodian work assignments defined by the manager are simulated for the entire year. Clustering and routing algorithms assign work to custodians equally and find optimal cleaning routes. The manager may use the resulting feedback to iteratively find a suitable schedule which lowers costs. Findings Data were collected at a large university building in consultation with facility management and custodians. Results indicate a significant reduction in overtime hours, improvement in utilisation difference and a lowering of labour costs. Research limitations/implications The methodology was validated at a single building in the facility. Variable selection and optimisation model design will benefit from a comprehensive case study which spans the entire facility. Practical implications The methodology may easily be integrated with existing facility maintenance software, adding to it features such as a manager scheduling interface with feedback on critical cleaning metrics and a custodian user interface which highlights room visitation routes and task times. Originality/value This study acts on the need for facility cleaning labour cost management highlighted in literature. It achieves its goals using a novel combination of scheduling, simulation and optimisation. It is designed to empower key decision-makers, i.e. facility managers and custodians, with better information.
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Wang, Linjie, Pengtu Zhang, Yali Geng, Zaisheng Zhu y Shiling Yuan. "Harmonic Vibrational Frequency Simulation of Pharmaceutical Molecules via a Novel Multi-Molecular Fragment Interception Method". Molecules 28, n.º 12 (8 de junio de 2023): 4638. http://dx.doi.org/10.3390/molecules28124638.
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By means of a computational method based on Density Functional Theory (DFT), using commercially available software, a novel method for simulating equilibrium geometry harmonic vibrational frequencies is proposed. Finasteride, Lamivudine, and Repaglinide were selected as model molecules to study the adaptability of the new method. Three molecular models, namely the single-molecular, central-molecular, and multi-molecular fragment models, were constructed and calculated by Generalized Gradient Approximations (GGAs) with the PBE functional via the Material Studio 8.0 program. Theoretical vibrational frequencies were assigned and compared to the corresponding experimental data. The results indicated that the traditional single-molecular calculation and scaled spectra with scale factor exhibited the worst similarity for all three pharmaceutical molecules among the three models. Furthermore, the central-molecular model with a configuration closer to the empirical structure resulted in a reduction of mean absolute error (MAE) and root mean squared error (RMSE) in all three pharmaceutics, including the hydrogen-bonded functional groups. However, the improvement in computational accuracy for different drug molecules using the central-molecular model for vibrational frequency calculation was unstable. Whereas, the new multi-molecular fragment interception method showed the best agreement with experimental results, exhibiting MAE and RMSE values of 8.21 cm−1 and 18.35 cm−1 for Finasteride, 15.95 cm−1 and 26.46 cm−1 for Lamivudine, and 12.10 cm−1 and 25.82 cm−1 for Repaglinide. Additionally, this work provides comprehensive vibrational frequency calculations and assignments for Finasteride, Lamivudine, and Repaglinide, which have never been thoroughly investigated in previous research.
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Wagner, Jennifer A., Gabriela Pabon, David Terrill y Susan M. Abdel-Rahman. "Examining a New Scale for Evaluating Taste in Children (TASTY)". Journal of Pediatric Pharmacology and Therapeutics 25, n.º 2 (1 de marzo de 2020): 131–38. http://dx.doi.org/10.5863/1551-6776-25.2.131.
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OBJECTIVES Pediatric medication taste impacts adherence, and current recommendations advocate for direct input from pediatric patients on medication taste during drug development. However, the lack of a widely used, validated measurement tool limits taste assessments. This protocol examines the validity of, and preferences for, a newly created self-report taste rating scale designed with images centered on taste (TASTY), compared with 2 existing hedonic taste scales. METHODS This study was a prospective, single-center, randomized survey of child-parent dyads recruited from pediatric ambulatory care clinics and ancillary service waiting rooms. Parents facilitated the survey by identifying foods that they perceived their child would recall as pleasant, neutral, and unpleasant. Children were asked to rate each of the 3 food items on each of 3 different faces scales presented in random order. Parents and children were also asked which scale they preferred and why. RESULTS Ninety child-parent dyads completed this study (mean child age was 6.7 ± 2.9 years, 58% female). All 3 scales performed comparably with no significant differences (p > 0.05). However, concordance between parental assignment and child rankings was markedly lower in 3-year-olds (r < 0.4) and 4-year-olds (r < 0.6) than for children 5 years and older (r > 0.9). TASTY was preferred by both parents and children when compared with the other scales. CONCLUSIONS This novel hedonic taste scale for pediatric use is equally valid and preferred to comparable faces scales. The TASTY scale may be beneficial in developing standardized methodology for evaluating drug palatability.
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Iwuji, P. C. "PERFORMANCE ANALYSIS AND DEVELOPMENT OF PATH LOSS MODEL FOR TELEVISION SIGNALS IN IMO STATE, NIGERIA". Eurasian Physical Technical Journal 20, n.º 2 (44) (21 de junio de 2023): 87–98. http://dx.doi.org/10.31489/2023no2/87-98.
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It is impossible to overstate the importance of propagation models in wireless network planning, frequency assignment, and television parameter evaluation. The fact that no two locations are identical in terms of climatic conditions, building patterns, terrain, etc. makes using path loss predicting models for any area extremely challenging. Therefore, it is impossible to develop a single path loss model that applies to all environmental settings. The main aim of this study is to develop a path loss model for NTA channel 12 Owerri and evaluate its performance based on received signal strength values along five selected routes in Imo State, Nigeria.A suitable path loss model was developed by critically analyzing the measured path loss values of each base station, which were retrieved from the signal strength data received. The values of the developed path loss model were compared to those of other empirical path loss models developed by other researchers as well as the measured path loss values. The results show that the proposed path loss model is well suited for predicting the path loss of NTA channel 12 Owerri signals in the study environment, while the other conventional empirical models taken into consideration in this study overestimated the path loss of NTA channel 12 Owerri signals with Root Mean Square Error and Mean Error of 63.65 and above. Additionally, the findings indicate that NTA Owerri performs poorly at a distance of 18 kilometers from the base transmitting station. The overall findings are helpful for designing prospective television network channels in the study location and other similar environments.
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Wang, Walsh y Koirala. "Mango Fruit Load Estimation Using a Video Based MangoYOLO—Kalman Filter—Hungarian Algorithm Method". Sensors 19, n.º 12 (18 de junio de 2019): 2742. http://dx.doi.org/10.3390/s19122742.
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: Pre-harvest fruit yield estimation is useful to guide harvesting and marketing resourcing, but machine vision estimates based on a single view from each side of the tree (“dual-view”) underestimates the fruit yield as fruit can be hidden from view. A method is proposed involving deep learning, Kalman filter, and Hungarian algorithm for on-tree mango fruit detection, tracking, and counting from 10 frame-per-second videos captured of trees from a platform moving along the inter row at 5 km/h. The deep learning based mango fruit detection algorithm, MangoYOLO, was used to detect fruit in each frame. The Hungarian algorithm was used to correlate fruit between neighbouring frames, with the improvement of enabling multiple-to-one assignment. The Kalman filter was used to predict the position of fruit in following frames, to avoid multiple counts of a single fruit that is obscured or otherwise not detected with a frame series. A “borrow” concept was added to the Kalman filter to predict fruit position when its precise prediction model was absent, by borrowing the horizontal and vertical speed from neighbouring fruit. By comparison with human count for a video with 110 frames and 192 (human count) fruit, the method produced 9.9% double counts and 7.3% missing count errors, resulting in around 2.6% over count. In another test, a video (of 1162 frames, with 42 images centred on the tree trunk) was acquired of both sides of a row of 21 trees, for which the harvest fruit count was 3286 (i.e., average of 156 fruit/tree). The trees had thick canopies, such that the proportion of fruit hidden from view from any given perspective was high. The proposed method recorded 2050 fruit (62% of harvest) with a bias corrected Root Mean Square Error (RMSE) = 18.0 fruit/tree while the dual-view image method (also using MangoYOLO) recorded 1322 fruit (40%) with a bias corrected RMSE = 21.7 fruit/tree. The video tracking system is recommended over the dual-view imaging system for mango orchard fruit count.
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Xia, Xue, Xiujuan Chai, Ning Zhang, Zhao Zhang, Qixin Sun y Tan Sun. "Culling Double Counting in Sequence Images for Fruit Yield Estimation". Agronomy 12, n.º 2 (10 de febrero de 2022): 440. http://dx.doi.org/10.3390/agronomy12020440.
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Exact yield estimation of fruits on plants guaranteed fine and timely decisions on harvesting and marketing practices. Automatic yield estimation based on unmanned agriculture offers a viable solution for large orchards. Recent years have witnessed notable progress in computer vision with deep learning for yield estimation. Yet, the current practice of vision-based yield estimation with successive frames may engender fairly great error because of the double counting of repeat fruits in different images. The goal of this study is to provide a wise framework for fruit yield estimation in sequence images. Specifically, the anchor-free detection architecture (CenterNet) is utilized to detect fruits in sequence images from videos collected in the apple orchard and orange orchard. In order to avoid double counts of a single fruit between different images in an image sequence, the patch matching model is designed with the Kuhn–Munkres algorithm to optimize the paring process of repeat fruits in a one-to-one assignment manner for the sound performance of fruit yield estimation. Experimental results show that the CenterNet model can successfully detect fruits, including apples and oranges, in sequence images and achieved a mean Average Precision (mAP) of 0.939 under an IoU of 0.5. The designed patch matching model obtained an F1-Score of 0.816 and 0.864 for both apples and oranges with good accuracy, precision, and recall, which outperforms the performance of the reference method. The proposed pipeline for the fruit yield estimation in the test image sequences agreed well with the ground truth, resulting in a squared correlation coefficient of R2apple = 0.9737 and R2orange = 0.9562, with a low Root Mean Square Error (RMSE) for these two varieties of fruit.
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Rahimi, Amin, Seyed Mojtaba Hejazi, Mostafa Zandieh y Mirpouya Mirmozaffari. "A Novel Hybrid Simulated Annealing for No-Wait Open-Shop Surgical Case Scheduling Problems". Applied System Innovation 6, n.º 1 (17 de enero de 2023): 15. http://dx.doi.org/10.3390/asi6010015.
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In this paper, the problem of finding an assignment of “n” surgeries to be presented in one of “m” identical operating rooms (ORs) or machines as the surgical case scheduling problem (SCSP) is proposed. Since ORs are among NP-hard optimization problems, mathematical and metaheuristic methods to address OR optimization problems are used. The job or surgical operation ordering in any OR is a permanent part of all sequencing and scheduling problems. The transportation times between ORs are defined based on the type of surgical operations and do not depend on distance, so there is no surgical operation waiting time for transferring. These problems are called no-wait open-shop scheduling problems (NWOSP) with transportation times. The transportation system for the problems is considered a multi-transportation system with no limitation on the number of transportation devices. Accordingly, this study modeled a novel combined no-wait open-shop surgical case scheduling problem (NWOSP-SCSP) with multi-transportation times for the first time to minimize the maximum percentile of makespan for OR as a single objective model. A mixed-integer linear program (MILP) with small-sized instances is solved. In addition to the small-sized model, a novel metaheuristic based on a hybrid simulated annealing (SA) algorithm to solve large-sized problems in an acceptable computational time is suggested, considering the comparison of the SA algorithm and a new recommended heuristic algorithm. Then, the proposed hybrid SA and SA algorithms are compared based on their performance measurement. After reaching the results with a numerical analysis in Nova Scotia health authority hospitals and health centers, the hybrid SA algorithm has generated significantly higher performance than the SA algorithm.