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We study the propagation and wall scattering of two-dimensional thermodynamic disturbances in a gas at non-continuum conditions. Initial system perturbations are modelled as arbitrary (local) small-amplitude density or temperature inhomogeneities, prescribed in the vicinity of an impermeable specular or diffuse (isothermal) wall. The problem is analyzed in the free-molecular and ideal-flow limits, complemented by Direct Simulation Monte Carlo (DSMC) calculations at arbitrary rarefaction rates. Closed-form results are obtained for the collisionless and ideal-flow gas responses to impulse excitation, followed by comparisons between DSMC and limit-case predictions for the case of Gaussian perturbations. While the acoustic signal is subject only to a “geometric” two-dimensional decay and carries to large distances in the inviscid limit, it decays rapidly at high rarefaction rates due to the mechanism of molecular dispersion. Different from the identical gas responses to local compression and heating in the inviscid regime, qualitative differences are highlighted and analyzed in the free-molecular limit. The results additionally indicate lower pressure levels in an isothermalcompared with a specular-wall system, due to the exchange of gas-surface energy taking place in the former. Finally, the acoustic force acting on the solid surface is examined. Apart from an early-time repelling impact, late-time attraction is found in the case of gas heating excitation at high Knudsen numbers.

A 30-year-old female with no significant past medical history presented to our labor and delivery ward for induction of labor. Due to failure to progress, she was proceeded to cesarean delivery. Intraoperatively, it was noted that her uterus was hypotonic; she required supplemental methylergometrine to control the bleeding from the uterine atony. However, within three minutes of intramuscular (IM) administration, she complained of chest pain. She then subsequently developed pulmonary edema in the postoperative care unit, which required supplemental oxygen. She was found to have elevated troponin and brain natriuretic peptide (BNP), along with radiologic features of fluid overload suggestive of congestive cardiac failure, which all lead to the diagnosis of non-ST myocardial infarction. The patient had a normal computed tomography (CT) pulmonary angiogram, echocardiogram, and serial electrocardiograms (ECGs). She was successfully discharged from the hospital on postoperative day 4 with resolution of her symptoms and improving cardiac enzymes. Cardiology outpatient follow-up was arranged.

Bacterial type IV secretion systems (T4SSs) can mediate conjugation. The T4SS from Neisseria gonorrhoeae possesses the unique ability to mediate DNA secretion into the extracellular environment. The N. gonorrhoeae T4SS can be grouped with F-type conjugative T4SSs based on homology. We tested 17 proteins important for DNA secretion by N. gonorrhoeae for protein interactions. The BACTH-TM bacterial two-hybrid system was successfully used to study periplasmic interactions. By determining if the same interactions were observed for F-plasmid T4SS proteins and when one interaction partner was replaced by the corresponding protein from the other T4SS we aimed to identify features associated with the unique function of the N. gonorrhoeae T4SS as well as generic features of F-type T4SSs. For both systems, we observed already described interactions shared by homologs from other T4SSs as well as new and described interactions between F-type T4SS specific proteins. Furthermore, we demonstrate, for the first-time, interactions between proteins with homology to the conserved T4SS outer membrane core proteins and F-type specific proteins and we confirmed two of them by co-purification. The F-type specific protein TraH(N) was found to localize to the outer membrane and the presence of significant amounts of TraH(N) in the outer membrane requires TraG(N).

Chronic Helicobacter pylori (Hp) infection is considered to be the single most important risk factor for the development of gastric adenocarcinoma in humans, which is a leading cause of cancer-related death worldwide. Nonetheless, Hp infection does not always progress to malignancy, and, gastric adenocarcinoma can occur in the absence of detectable Hp carriage, highlighting the complex and multifactorial nature of gastric cancer. Here we review known contributors to gastric malignancy, including Hp virulence factors, featuring the vacuolating cytotoxin (VacA), the cytotoxin-associated gene A (CagA), and other bacterial components that promote chemotaxis, colonization, and the establishment of chronic inflammation. In addition, we discuss host factors including sex, age, and genetic polymorphisms associated with host inflammation. Moreover, we consider environmental variables that influence cancer risk, such as nutritional status, socio-economic status, and smoking. In addition to these relatively well-studied contributors to gastric cancer risk, the resident gastric microflora in humans have more recently been proposed as an additional risk factor for disease progression in Hp-infected individuals. Molecular approaches for microbe identification have revealed differences in the gastric microbiota composition between cancer and non-cancerous patients, as well as infected and uninfected individuals. Although the reasons underlying differences in microbial community structures are not entirely understood, gastric atrophy and hypochlorhydria that accompany chronic Hp infection may be a critical driver of gastric dysbiosis that promote colonization of microbes that contribute to increased risk of malignancy. However, definitive evidence that the gastric microbiota influences the emergence of gastric cancer does not exist. In summary, while controversial and unresolved, the importance of the gastric microbiota as a risk factor for gastric malignancy is a vital area of current research.

Group 4 (Ti and Zr) and 5 (Nb and Ta) atoms substituted into the *BEA zeolite framework (M-BEA) irreversibly activate hydrogen peroxide (H2O2) and form pools of metal-hydroperoxide (M-OOH) and peroxide (M-(η2-O2)) intermediates active for the oxidation of 2,5-dimethylthiophene (C6H8S), a model reactant representative of organosulfur species in fossil reserves and chemical weapons. Sequential oxidation pathways convert C6H8S into 2,5-dimethylthiophene oxide (C6H8SO) and subsequently into 2,5-dimethylthiophene dioxide by oxidative dearomatization. Oxidation rates measured as functions of reactant concentrations together with in situ UV–vis spectra show that all M-BEA activate H2O2 to form pools of M-OOH and M-(η2-O2), which then react with either C6H8S or H2O2 to form the sulfoxide or to decompose into H2O and O2, respectively. Turnover rates for C6H8S oxidation and H2O2 decomposition both increase exponentially with the electron affinity of the active site, which is quantitatively probed via the adsorption enthalpy for deuterated acetonitrile to active sites. C6H8S oxidation rates depend also on the nucleophilicity of the solvent used, and rates decrease in the order acetonitrile > p-dioxane ∼ acetone > ethanol ∼ methanol. In situ UV–vis spectra show that highly nucleophilic solvent molecules compete effectively for active sites, inhibit H2O2 activation and formation of reactive M-OOH and M-(η2-O2) species, and give lower turnover rates. Consequently, this work shows that turnover rates for sulfoxidation are highest when highly electrophilic active sites (i.e., stronger Lewis acids) are paired with weakly nucleophilic solvents, which can guide the design of increasingly productive catalytic systems for sulfide oxidation.

Hydrophobic voids within titanium silicates have long been considered necessary to achieve high rates and selectivities for alkene epoxidations with H2O2. The catalytic consequences of silanol groups and their stabilization of hydrogen-bonded networks of water (H2O), however, have not been demonstrated in ways that lead to a clear understanding of their importance. We compare turnover rates for 1-octene epoxidation and H2O2 decomposition over a series of Ti-substituted zeolite *BEA (Ti-BEA) that encompasses a wide range of densities of silanol nests ((SiOH)4). The most hydrophilic Ti-BEA gives epoxidation turnover rates that are 100 times larger than those in defect-free Ti-BEA, yet rates of H2O2 decomposition are similar for all (SiOH)4 densities. These differences cause the most hydrophilic Ti-BEA to also give the highest selectivities, which defies conventional wisdom. Spectroscopic, thermodynamic, and kinetic evidence indicate that these catalytic differences are not due to changes in the electronic affinity of the active site, the electronic structure of Ti-OOH intermediates, or the mechanism for epoxidation. Comparisons of apparent activation enthalpies and entropies show that differences in epoxidation rates and selectivities reflect favorable entropy gains produced when epoxidation transition states disrupt hydrogen-bonded H2O clusters anchored to (SiOH)4 near active sites. Transition states for H2O2 decomposition hydrogen bond with H2O in ways similar to Ti-OOH reactive species, such that decomposition becomes insensitive to the presence of (SiOH)4. Collectively, these findings clarify how molecular interactions between reactive species, hydrogen-bonded solvent networks, and polar surfaces can influence rates and selectivities for epoxidation (and other reactions) in zeolite catalysts.

Human monkeypox, an infectious disease caused by monkeypox virus (MPXV), is endemic to western and central Africa. A LightCycler quantitative PCR (LC-qPCR) system was developed for the diagnosis of this disease, targeting the A-type inclusion body gene (ATI gene) of MPXV. One naive monkey was infected with MPXV Zr-599 (Congo Basin strain) and one with MPXV Liberia (West African strain). Another three monkeys were immunized with smallpox vaccine on 0, 3, or 7 days, respectively, before infection with MPXV Zr-599. Peripheral blood cell (PBC) and throat swab (TS) specimens were serially collected. The LC-qPCR was validated for the diagnosis of monkeypox using virus isolation. Sequencing of the partial ATI gene revealed the insertion of a unique 453-nucleotide residue in the West African strains but not in the Congo Basin strains. Specific reverse primers for Congo Basin and West African strains were designed based on the unique sequence insertion. The LC-qPCR detected the MPXV genome, but not those of the other orthopoxviruses tested nor the varicella-zoster virus. Both the sensitivity and specificity of the LC-qPCR were over 90% in comparison to virus isolation when TS specimens were tested. Fourteen of the 15 virus isolation-positive PBC specimens showed positive reactions in the assay. Further, most PBC specimens collected from symptomatic monkeys in the later stage of illness showed positive reactions in the assay but negative reaction in virus isolation. It was possible to differentiate between these two groups with the LC-qPCR. Thus, the newly developed LC-qPCR is a useful and reliable diagnostic tool for MPXV infection.

Diabetic foot lesions are a major medical, social, and economic problem and are the leading cause of hospitalization for patients with diabetes, worldwide. ESBL-producing bacteria may not be detectable by routine disc diffusion susceptibility test, leading to inappropriate use of antibiotics and treatment failure. There is not much information on ESBL-producing organisms causing diabetic foot infection. An attempt was therefore made to study the ESBL-producing Escherichia coli and Klebsiella pneumoniae in diabetic foot patients with type 2 diabetes mellitus.A total of 134 isolates of E. coli and K. pneumoniae were obtained from tissue, pus swab, and wound swab samples from diabetic foot ulcers submitted for routine microbiological analysis during the period January to December 2005 from patients with diabetic foot infections who had type 2 diabetes mellitus, attending S. L. Raheja Hospital. The above isolates were tested for antimicrobial susceptibility by disc diffusion technique according to clinical and laboratory standards institute (CLSI) guidelines. The screening for ESBL production was done by phenotypic confirmatory test using ceftazidime disc in the presence and absence of clavulanic acid as recommended by CLSI.Among the 134 isolates, 54 (40.29%) were E. coli and 80 (59.70%) were K. pneumoniae; among which, ESBL production was detected in 31 (23.13%) isolates. Of these 31, 15 (48.38%) were E. coli and 16 (51.61%) were K. pneumoniae. All the ESBL-producing isolates were found to be 100% sensitive to carbapenem (imipenem and meropenem). Mortality was found to be 3.22%, the cause of death being septicemia leading to multiple organ failure.The prevalence of ESBLs among members of Enterobacteriaceae constitutes a serious threat to the current beta-lactam therapy, leading to treatment failure and consequent escalation of costs. There is an urgent need to emphasize rational use of drugs to minimize the misuse of available antimicrobials.