Studies of protein structure and genome evolution

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Job Satisfaction Among Methadone Maintenance Treatment Clinic Service Providers in Jiangsu, China: A Cross-sectional Survey.

ObjectiveService providers' job satisfaction is critical to the stability of the work force and thereby the effectiveness of methadone maintenance treatment (MMT) programs. This study aimed to explore MMT clinic service providers' job satisfaction and associated factors in Jiangsu, China.MethodsThis secondary study used baseline data of a randomized interventional trial implemented in Jiangsu, China. A survey was conducted among 76 MMT service providers using the computer-assisted self-interview (CASI) method. Job satisfaction responses were assessed via a 30-item scale, with a higher score indicating a higher level of job satisfaction. Perceived institutional support and perceived stigma due to working with drug users were measured using a 9-item scale. Correlation and multiple linear regression analyses were performed to identify factors associated with job satisfaction.ResultsCorrelation analyses found a significant association between job satisfaction and having professional experience in the prevention and control of HIV, other sexually transmitted infections, or other infectious diseases (P = 0.046). Multiple regression analyses revealed that working at MMT clinics affiliated with Center for Disease Control and Prevention sites was associated with a lower level of job satisfaction (P = 0.014), and perception of greater institutional support (P = 0.001) was associated with a higher level of job satisfaction.ConclusionJob satisfaction among MMT clinic service providers was moderate in our study. Our findings suggest that institutional support for providers should be improved, and that acquisition of additional expertise should be encouraged

Percutaneous Endoscopic Gastrostomy in the Enteral Feeding of the Elderly

SummaryToday we are faced with an aging society that may develop malnutrition because of dysphagia related to dementia, stroke, and malignancy seen often in the elderly. The preferred form of nutritional supplementation for this group is enteral nutrition, and the most appropriate long-term method is by use of a gastrostomy. Percutaneous endoscopic gastrostomy (PEG) was first introduced in 1980 as an alternative to the traditional operative procedure and rapidly became the preferred procedure. In geriatric patients, the principal indications are neurological dysphagia and malnutrition, related to an underlying disease or anorexia-cachexia in very elderly. PEG is contraindicated in the presence of respiratory distress, previous gastric resection, total esophageal obstruction, coagulation disorders and sepsis in the elderly. Common complications include wound infection, leakage, hemorrhage, and fistula in the general population, but aspiration pneumonia is the major case of death in this group. Risks and complications of PEG must be discussed with patients and their families; and the decision for percutaneous endoscopic gastrostomy insertion should only be made after careful consideration and discussion between managing physicians, allied health professionals, and the patient and/or family. Four ethical principles may help make feeding decisions: beneficence, non-maleficence, autonomy and justice. Attentive long-term care after tube replacement is mandatory. Acceptance of percutaneous endoscopic gastrostomy placement by patients and their families tends to increase once favorable outcomes are offered

Generating Function for Tensor Network Diagrammatic Summation

The understanding of complex quantum many-body systems has been vastly boosted by tensor network (TN) methods. Among others, excitation spectrum and long-range interacting systems can be studied using TNs, where one however confronts the intricate summation over an extensive number of tensor diagrams. Here, we introduce a set of generating functions, which encode the diagrammatic summations as leading order series expansion coefficients. Combined with automatic differentiation, the generating function allows us to solve the problem of TN diagrammatic summation. We illustrate this scheme by computing variational excited states and dynamical structure factor of a quantum spin chain, and further investigating entanglement properties of excited states. Extensions to infinite size systems and higher dimension are outlined.Comment: v1: 6 pages, 2 figures. v2: published versio

Bis(2-amino­pyrimidine-κN 1)dibromidozinc(II)

The title compound, [ZnBr2(C4H5N3)2], is a mononuclear complex in which the ZnII ions have distorted tetra­hedral coordination geometry. The ZnII ion binds to two N atoms from two different 2-amino­pyrimidine ligands and two bromide ions. N—H⋯N hydrogen bonds link the mol­ecules to form a one-dimensional supra­molecular structure. The supra­molecular chains are parallel to each other and N—H⋯Br hydrogen bonds link them into a two-dimensional network in the ac plane. Additionally, there are strong π–π inter­actions [centroid–centroid distance = 3.403 (3) Å]

Field-induced easy-axis softening of quantum ferromagnet with cubic anisotropy

In this work, we study the two-dimensional $S=2$ model that can lead to the well-known cubic single-ion anisotropy along with a ferromagnetic Heisenberg interaction under a perpendicular magnetic field. When the Heisenberg term ($J$) is ignored, this model can be exactly solved with a reshuffled local Hilbert space. A three-fold (two-fold) eigenstate degeneracy is found at $h=0$ ($h=2K$), where $h$ stands for the field strength and $K$ is the strength of cubic anisotropy. Around the second degeneracy point there is a huge gap that separates two low-energy states from the rest three. As we turn on the $J$ term, its leading-order contribution boils down to an effective hard-core bosonic model as $K,h\gg J$. By using the two-dimensional tensor network ansatz we reveal that indeed various ground-state ansatz with different magnetic easy axes possess competing energies. Our finding demonstrates that the easy axes can be "softened" as we turn on the magnetic field for such quantum model with cubic anisotropy, which goes beyond the mean-field analysis. Such easy-axis softening might provide a new measure to control the magnetic orientation for spinful semiconductors.Comment: 10 pages, 5 figures, 1 Tabl

An optimized procedure greatly improves EST vector contamination removal

<p>Abstract</p> <p>Background</p> <p>The enormous amount of sequence data available in the public domain database has been a gold mine for researchers exploring various themes in life sciences, and hence the quality of such data is of serious concern to researchers. Removal of vector contamination is one of the most significant operations to obtain accurate sequence data containing only a cDNA insert from the basecalls output by an automatic DNA sequencer. Popular bioinformatics programs to accomplish vector trimming include LUCY, cross_match and SeqClean.</p> <p>Results</p> <p>In a recent study, where the program SeqClean was used to remove vector contamination from our test set of EST data compiled through various library construction systems, however, a significant number of errors remained after preliminary trimming. These errors were later almost completely corrected by simply using a re-linearized form of the cloning vector to compare against the target ESTs. The modified trimming procedure for SeqClean was also compared with the trimming efficiency of the other two popular programs, LUCY2, and cross_match. Using SeqClean with a re-linearized form of the cloning vector significantly surpassed the other two programs in all tested conditions, while the performance of the other two programs was not influenced by the modified procedure. Vector contamination in dbEST was also investigated in this study: 2203 out of the 48212 ESTs sampled from dbEST (2007-04-18 freeze) were found to match sequences in UNIVEC.</p> <p>Conclusion</p> <p>Vector contamination remains a serious concern to the data quality in the public sequence database nowadays. Based on the results presented here, we feel that our modified procedure with SeqClean should be recommended to all researchers for the task of vector removal from EST or genomic sequences.</p