Gas hydrate inhibition by perturbation of liquid water structure

Natural gas hydrates are icy crystalline materials that contain hydrocarbons, which are the primary energy source for this civilization. The abundance of naturally occurring gas hydrates leads to a growing interest in exploitation. Despite their potential as energy resources and in industrial applications, there is insufficient understanding of hydrate kinetics, which hinders the utilization of these invaluable resources. Perturbation of liquid water structure by solutes has been proposed to be a key process in hydrate inhibition, but this hypothesis remains unproven. Here, we report the direct observation of the perturbation of the liquid water structure induced by amino acids using polarized Raman spectroscopy, and its influence on gas hydrate nucleation and growth kinetics. Amino acids with hydrophilic and/or electrically charged side chains disrupted the water structure and thus provided effective hydrate inhibition. The strong correlation between the extent of perturbation by amino acids and their inhibition performance constitutes convincing evidence for the perturbation inhibition mechanism. The present findings bring the practical applications of gas hydrates significantly closer, and provide a new perspective on the freezing and melting phenomena of naturally occurring gas hydrates.112716Ysciescopu

Hypertension Programmed in Adult Hens by Isolated Effects of Developmental Hypoxia In Ovo.

In mammals, pregnancy complicated by chronic hypoxia can program hypertension in the adult offspring. However, mechanisms remain uncertain because the partial contributions of the challenge on the placenta, mother, and fetus are difficult to disentangle. Here, we used chronic hypoxia in the chicken embryo-an established model system that permits isolation of the direct effects of developmental hypoxia on the cardiovascular system of the offspring, independent of additional effects on the mother or the placenta. Fertilized chicken eggs were exposed to normoxia (N; 21% O2) or hypoxia (H; 13.5%-14% O2) from the start of incubation (day 0) until day 19 (hatching, ≈day 21). Following hatching, all birds were maintained under normoxic conditions until ≈6 months of adulthood. Hypoxic incubation increased hematocrit (+27%) in the chicken embryo and induced asymmetrical growth restriction (body weight, -8.6%; biparietal diameter/body weight ratio, +7.5%) in the hatchlings (all P<0.05). At adulthood (181±4 days), chickens from hypoxic incubations remained smaller (body weight, -7.5%) and showed reduced basal and stimulated in vivo NO bioavailability (pressor response to NG-nitro-L-arginine methyl ester, -43%; phenylephrine pressor response during NO blockade, -61%) with significant hypertension (mean arterial blood pressure, +18%), increased cardiac work (ejection fraction, +12%; fractional shortening, +25%; enhanced baroreflex gain, +456%), and left ventricular wall thickening (left ventricular wall volume, +36%; all P<0.05). Therefore, we show that chronic hypoxia can act directly on a developing embryo to program hypertension, cardiovascular dysfunction, and cardiac wall remodeling in adulthood in the absence of any maternal or placental effects.The British Heart Foundation The Wellcome Trus

Abnormal variation of band gap in Zn doped Bi0.9La0.1FeO3 nanoparticles: Role of Fe-O-Fe bond angle and Fe-O bond anisotropy

published_or_final_versio

Spatially Bandgap-Graded MoS₂₍₁-ₓ₎Se₂ₓ Homojunctions for Self-Powered Visible–Near-Infrared Phototransistors

Ternary transition metal dichalcogenide alloys with spatially graded bandgaps are an emerging class of two-dimensional materials with unique features, which opens up new potential for device applications. Here, visible–near-infrared and self-powered phototransistors based on spatially bandgap-graded MoS2(1−x)Se2x alloys, synthesized by a simple and controllable chemical solution deposition method, are reported. The graded bandgaps, arising from the spatial grading of Se composition and thickness within a single domain, are tuned from 1.83 to 1.73 eV, leading to the formation of a homojunction with a built-in electric field. Consequently, a strong and sensitive gate-modulated photovoltaic effect is demonstrated, enabling the homojunction phototransistors at zero bias to deliver a photoresponsivity of 311 mA W−1, a specific detectivity up to ~ 1011 Jones, and an on/off ratio up to ~ 104. Remarkably, when illuminated by the lights ranging from 405 to 808 nm, the biased devices yield a champion photoresponsivity of 191.5 A W−1, a specific detectivity up to ~ 1012 Jones, a photoconductive gain of 106–107, and a photoresponsive time in the order of ~ 50 ms. These results provide a simple and competitive solution to the bandgap engineering of two-dimensional materials for device applications without the need for p–n junctions

Study on mNGS Technique in Diagnosing Pneumocystis jirovecii Pneumonia in Non-HIV-Infected Patients

Shuai Li, Xue Han, Jing Ma, Guo-Hong Huang, Shu-Ting Yang, Chang-Min Wang Clinical Laboratory Center, People’s Hospital of Xinjiang Uygur Autonomous Region, Urumqi, Xinjiang, 830001, People’s Republic of ChinaCorrespondence: Chang-Min Wang, Department of Clinical Laboratory Center, People’s Hospital of Xinjiang Uygur Autonomous Region, No. 91 Tianchi Street, Tianshan District, Urumqi, Xinjiang, 830001, People’s Republic of China, Tel +86 13609992616, Fax +86− 9918564168, Email [email protected]: To investigate the value of metagenomic Next-Generation Sequencing (mNGS) in diagnosing Pneumocystis jirovecii pneumonia (PJP) in non-human immunodeficiency virus (HIV)-infected patients.Methods: In this retrospective study, non-HIV-infected patients with PJP and those diagnosed with non-PJP from August 2022 to December 2024 were selected as subjects. The presence of Pneumocystis jirovecii (PJ) and other co-pathogens in bronchoalveolar lavage fluid (BALF) was analyzed, and the diagnostic efficacy of NGS, polymerase chain reaction (PCR) and serum 1,3-β-D-glucan (BDG) in PJP was compared with the reference standard of clinical compound diagnosis.Results: Eighty-nine non-HIV-infected patients were recruited, with dyspnea as the primary symptom (69.66%) and solid malignant tumor as the most common underlying disease (20.22%). Taking clinical compound diagnosis as the reference standard, the sensitivity, specificity, negative predictive value and positive predictive value of mNGS were higher than those detected by PCR and serum BDG. Among 42 non-HIV-infected patients with PJP who underwent mNGS and conventional pathogen detection of BALF, 6 had simple PJ infection and 36 had combined PJ infection. The detection rate of mNGS in mixed infections was significantly higher than that of conventional pathogen detection (85.71 vs 61.70%, P = 0.012). A total of 127 pathogens were detected in BALF using mNGS, among which fungi had the highest detection rate (46.46%). The fungi, viruses and bacteria detected were mainly Pneumocystis jirovecii, human gammaherpesvirus 4 and Acinetobacter baumannii.Conclusion: mNGS is highly effective in diagnosing non-HIV-infected patients with PJP and exhibits ideal performance in the detection of co-pathogens. In addition, it has certain value for clinical diagnosis and guidance of targeted anti-infective drug treatment.Keywords: metagenomic next-generation sequencing, Pneumocystis jirovecii pneumonia, polymerase chain reaction, non-HIV infectio

Dietary Pattern Trajectories from 6 to 12 Months of Age in a Multi-Ethnic Asian Cohort

10.3390/nu8060365Nutrients86365GUSTO (Growing up towards Healthy Outcomes

Laser-induced etching of few-layer graphene synthesized by Rapid-Chemical Vapour Deposition on Cu thin films

The outstanding electrical and mechanical properties of graphene make it very attractive for several applications, Nanoelectronics above all. However a reproducible and non destructive way to produce high quality, large-scale area, single layer graphene sheets is still lacking. Chemical Vapour Deposition of graphene on Cu catalytic thin films represents a promising method to reach this goal, because of the low temperatures (T < 900 Celsius degrees) involved during the process and of the theoretically expected monolayer self-limiting growth. On the contrary such self-limiting growth is not commonly observed in experiments, thus making the development of techniques allowing for a better control of graphene growth highly desirable. Here we report about the local ablation effect, arising in Raman analysis, due to the heat transfer induced by the laser incident beam onto the graphene sample.Comment: v1:9 pages, 8 figures, submitted to SpringerPlus; v2: 11 pages, PDFLaTeX, 9 figures, revised peer-reviewed version resubmitted to SpringerPlus; 1 figure added, figure 1 and 4 replaced,typos corrected, "Results and discussion" section significantly extended to better explain etching mechanism and features of Raman spectra, references adde

Effects of metal-contaminated soils on the accumulation of heavy metals in gotu kola (Centella asiatica) and the potential health risks: a study in Peninsular Malaysia

Centella asiatica is a commonly used medicinal plant in Malaysia. As heavy metal accumulation in medicinal plants which are highly consumed by human is a serious issue, thus the assessment of heavy metals in C. asiatica is important for the safety of consumers. In this study, the heavy metal accumulation in C. asiatica and the potential health risks were investigated. Samples of C. asiatica and surface soils were collected from nine different sites around Peninsular Malaysia. The concentration of six heavy metals namely Cd, Cu, Ni, Fe, Pb and Zn were determined by air-acetylene flame atomic absorption spectrophotometer (AAS). The degree of anthropogenic influence was assessed by calculating the enrichment factor (EF) and index of geoaccumulation (Igeo). The heavy metal uptake into the plant was estimated through the calculation of translocation factor (TF), bioconcentration factor (BCF) and correlation study. Estimated daily intakes (EDI) and target hazard quotients (THQ) were used to determine the potential health risk of consuming C. asiatica. The results showed that the overall surface soil was polluted by Cd, Cu and Pb, while the uptake of Zn and Ni by the plants was high. The value of EDI and THQ showed that the potential of Pb toxicity in C. asiatica was high as well. As heavy metal accumulation was confirmed in C. asiatica, daily consumption of the plant derived from polluted sites in Malaysia was not recommended

The Effect of N-nitrosodimethylamine (NDMA) on Bax and Mcl-1 Expression in Human Neutrophils

In the present study we examined a role of pro-apoptotic Bax and anti-apoptotic Mcl-1 proteins, participating in the regulation of intrinsic apoptosis pathway in human neutrophils (PMNs) exposed to N-nitrosodimethylamine (NDMA), the environmental xenobiotic. For the purpose comparison, the same studies were conducted in autologous peripheral blood mononuclear cells (PBMCs). The production of cytochrome c by PMNs was also determined. A deficit of anti-apoptotic Mcl-1 and overexpression of the pro-apoptotic protein Bax suggest that the apoptosis process in human neutrophils exposed to NDMA is dependent on changes in the expression of these proteins. PMNs were more sensitive to NDMA than PBMCs