Near-Infrared Variability Study of the Central 2.3 arcmin x 2.3 arcmin of the Galactic Centre I. Catalog of Variable Sources

We used four-year baseline HST/WFC3 IR observations of the Galactic Centre in the F153M band (1.53 micron) to identify variable stars in the central ~2.3'x2.3' field. We classified 3845 long-term (periods from months to years) and 76 short-term (periods of a few days or less) variables among a total sample of 33070 stars. For 36 of the latter ones, we also derived their periods (<3 days). Our catalog not only confirms bright long period variables and massive eclipsing binaries identified in previous works, but also contains many newly recognized dim variable stars. For example, we found \delta Scuti and RR Lyrae stars towards the Galactic Centre for the first time, as well as one BL Her star (period < 1.3 d). We cross-correlated our catalog with previous spectroscopic studies and found that 319 variables have well-defined stellar types, such as Wolf-Rayet, OB main sequence, supergiants and asymptotic giant branch stars. We used colours and magnitudes to infer the probable variable types for those stars without accurately measured periods or spectroscopic information. We conclude that the majority of unclassified variables could potentially be eclipsing/ellipsoidal binaries and Type II Cepheids. Our source catalog will be valuable for future studies aimed at constraining the distance, star formation history and massive binary fraction of the Milky Way nuclear star cluster.Comment: has been accepted to be published in MNRAS, 64 pages, 26 figures. The complete lists of table 3, 4, 8 and 9 will be published onlin

Stochastic Constrained Extended System Dynamics for Solving Charge Equilibration Models

We present a new stochastic extended Lagrangian solution to charge equilibration that eliminates self-consistent field (SCF) calculations, eliminating the computational bottleneck in solving the many-body solution with standard SCF solvers. By formulating both charges and chemical potential as latent variables, and introducing a holonomic constraint that satisfies charge conservation, the SC-XLMD method accurately reproduces structural, thermodynamic, and dynamics properties using ReaxFF, and shows excellent weak- and strong-scaling performance in the LAMMPS molecular simulation package

Social media and the modern scientist: a research primer for low- and middle-income countries

Social media has changed the way we communicate. Wherever you are in the world, various forms of social media are being used by individuals to share information and connect without borders. Due to its ubiquity, social media holds great promise in linking clinicians, scientists, investigators, and the public to change the way we conduct scientific discourse. In this paper, we present a step-by-step guide on optimizing your social media strategy with regards to: research/scholarly practice (discourse, collaboration, recruitment), knowledge translation, dissemination, and education. This guide also highlights key readings that provide guidance to those interested in incorporating social media into their scholarly practice. Social media has changed the way we communicate. Wherever you are in the world, various forms of social media are being used by individuals to share information and connect without borders. Due to its ubiquity, social media holds great promise in linking clinicians, scientists, investigators, and the public to change the way we conduct scientific discourse. In this paper, we present a step-by-step guide on optimizing your social media strategy with regards to: research/scholarly practice (discourse, collaboration, recruitment), knowledge translation, dissemination, and education. This guide also highlights key readings that provide guidance to those interested in incorporating social media into their scholarly practice

Dosage-Dependent Expression Variation Suppressed on the Drosophila Male X Chromosome.

DNA copy number variation is associated with many high phenotypic heterogeneity disorders. We systematically examined the impact of Drosophila melanogaster deletions on gene expression profiles to ask whether increased expression variability owing to reduced gene dose might underlie this phenotypic heterogeneity. Indeed, we found that one-dose genes have higher gene expression variability relative to two-dose genes. We then asked whether this increase in variability could be explained by intrinsic noise within cells due to stochastic biochemical events, or whether expression variability is due to extrinsic noise arising from more complex interactions. Our modeling showed that intrinsic gene expression noise averages at the organism level and thus cannot explain increased variation in one-dose gene expression. Interestingly, expression variability was related to the magnitude of expression compensation, suggesting that regulation, induced by gene dose reduction, is noisy. In a remarkable exception to this rule, the single X chromosome of males showed reduced expression variability, even compared with two-dose genes. Analysis of sex-transformed flies indicates that X expression variability is independent of the male differentiation program. Instead, we uncovered a correlation between occupancy of the chromatin-modifying protein encoded by males absent on the first (mof) and expression variability, linking noise suppression to the specialized X chromosome dosage compensation system. MOF occupancy on autosomes in both sexes also lowered transcriptional noise. Our results demonstrate that gene dose reduction can lead to heterogeneous responses, which are often noisy. This has implications for understanding gene network regulatory interactions and phenotypic heterogeneity. Additionally, chromatin modification appears to play a role in dampening transcriptional noise

Diabetic ketoacidosis induced by nivolumab in invasive mucinous adenocarcinoma of the lung : a case report and review of the literature

Nivolumab is the first programmed cell death receptor 1 (PD-1) inhibitor approved in China. Compared with chemotherapy, nivolumab has shown advantages of good efficacy and safety in the treatment of a variety of tumors. However, due to its short time of use in China and lack of safety experience, clinical understanding of its adverse reactions has not been sufficiently elucidated. In recent years, cases of diabetic ketoacidosis caused by nivolumab have been reported in the emergency department, which has aroused our concern. Here we present a serious case of diabetic ketoacidosis in a 69-year-old woman with invasive mucinous adenocarcinoma of the lung, which occurred following therapy with the PD-1 inhibitor nivolumab and dendritic cell/cytokine-induced killer cell (DC/CIK) immunotherapy. She presented with diabetic ketoacidosis 5 days after the second cycle of nivolumab administration. The patient presented with dry mouth symptoms, a maximum blood glucose of 511.2 mg/dL, hemoglobin A1c (HbA1c) level of 7.4%, urine ketone body value of 3+, and extracellular fluid residual alkali level of −3.8 mmol/L. Normal saline and insulin was initiated. The patient had no history of obesity or family history of diabetes. She received a single dose of 3.75 mg of dexamethasone treatment during this period of time which resulted in cough improvement, but did not explain the onset of the diabetes. She was treated with insulin, sitagliptin phosphate tablets and acarbose tablets. Diabetic ketoacidosis was considered an immune-related toxicity caused by nivolumab, and consequently, treatment with nivolumab was suspended. Patient was maintained under insulin treatment with a blood glucose levels normalization. The incubation period of nivolumab-induced diabetic ketoacidosis is dispersive and the clinical risk is high. Patients need life-long insulin therapy. Blood glucose and HbA1c should be monitored routinely before and during nivolumab immunotherapy to avoid the occurrence of diabetic ketoacidosis. After the occurrence of diabetic ketoacidosis, insulin should be used to actively control blood glucose and do a good job in medication education to ensure long-term compliance of patients. Nivolumab should only be initiated if the patient has a clinical benefit under stable glucose control

Improved Detection of Enterotoxigenic Escherichia coli among Patients with Travelers' Diarrhea, by Use of the Polymerase Chain Reaction Technique

This study sought to determine whether a specific polymerase chain reaction (PCR) for enterotoxigenic Escherichia coli (ETEC) toxins after chaotropic extraction of DNA from stool would increase the detection of ETEC over that of conventional oligonucleotide probe hybridization of 5 E. coli colonies per stool sample (a standard method). By DNA hybridization, 29 (21%) of 140 patients were positive for ETEC, and 59 (42%) of 140 were positive for ETEC when PCR was used. Sensitivity of the PCR assay was confirmed through spiked stool experiments to be ∼100-1000 ETEC colonies per sample. Specificity of the assay was determined by showing an absence of ETEC by the PCR technique in a subgroup of 48 subjects and by confirming the presence of ETEC DNA of positive samples by dot blot procedure. PCR technique detected significantly more ETEC infections in these subjects than did the hybridization method (P < .0001