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In our antioxidant screening of some Vietnamese plant extracts, the CHCl3-soluble fraction from Calotropis gigantea (L.) W.T.Aiton flowers showed moderate DPPH free radical scavenging activity with an IC50 value of 55.8 μg/mL. Thus, a further phytochemical study was carried out to obtain five alkaloids, including a new β-carboline-type alkaloid, caloside H (1). These known compounds were identified as 5-hydroxy-(2-methoxymethyl)pyridine (2), nicotinic acid (3), p-(acetylamino)phenol (4), and thymine (5). These structures were determined based on the NMR spectroscopic analysis. In antioxidant assay, caloside H at concentration of 100 μM showed DPPH radical scavenging capacity with a percentage of inhibition of 40.2%. In addition, a plausible biosynthetic pathway for the formation of caloside H was proposed based on the Schiff base formation and Mannich-like reaction. [ABSTRACT FROM AUTHOR]

Aim: Illicitly manufactured fentanyl and its analogs are the primary drivers of opioid overdose deaths in the United States (U.S.). People who use drugs may be exposed to fentanyl or its analogs intentionally or unintentionally. This study sought to identify strategies used by rural people who use drugs to reduce harms associated with unintentional fentanyl exposure. Methods: This analysis focused on 349 semi-structured qualitative interviews across 10 states and 58 rural counties in the U.S conducted between 2018 and 2020. Interview guides were collaboratively standardized across sites and included questions about drug use history (including drugs currently used, frequency of use, mode of administration) and questions specific to fentanyl. Deductive coding was used to code all data, then inductive coding of overdose and fentanyl codes was conducted by an interdisciplinary writing team. Results: Participants described being concerned that fentanyl had saturated the drug market, in both stimulant and opioid supplies. Participants utilized strategies including: (1) avoiding drugs that were perceived to contain fentanyl, (2) buying drugs from trusted sources, (3) using fentanyl test strips, 4) using small doses and non-injection routes, (5) using with other people, (6) tasting, smelling, and looking at drugs before use, and (7) carrying and using naloxone. Most people who used drugs used a combination of these strategies as there was an overwhelming fear of fatal overdose. Conclusion: People who use drugs living in rural areas of the U.S. are aware that fentanyl is in their drug supply and use several strategies to prevent associated harms, including fatal overdose. Increasing access to harm reduction tools (e.g., fentanyl test strips, naloxone) and services (e.g., community drug checking, syringe services programs, overdose prevention centers) should be prioritized to address the polysubstance-involved overdose crisis. These efforts should target persons who use opioids and other drugs that may contain fentanyl. [ABSTRACT FROM AUTHOR]

Background: The United States' (US) opioid overdose epidemic has evolved into a combined stimulant/opioid epidemic, a pattern driven in part by mitigating opioid overdose risk, variable substance availability, and personal preferences. This study aimed to investigate the association between self-reported substance preference (heroin or methamphetamine) and behavioral/health outcomes among individuals who used both heroin and methamphetamine in the rural US. Methods: The Rural Opioid Initiative is a consortium of 8 research cohorts from 10 states and 65 rural counties that recruited individuals reporting past 30-day injection of any substance or opioid substance use by any route from 1/2018 to 3/2020. Analyses were restricted to participants ⩾18 years, who self-reported either heroin or methamphetamine as their preferred substance and past 30-day use of both heroin and methamphetamine. We examined cross-sectional associations between preferred substance (heroin versus methamphetamine) and behavioral and health outcomes using random effects meta-analysis with adjusted regression models. Results: Among 1239 participants, 61% (n = 752) reported heroin as their preferred substance. Adjusting for age, sex, and race/ethnicity, methamphetamine preference was associated with lower prevalence ratios for current naloxone possession (adjusted prevalence ratio [aPR] = 0.68; 95% Confidence Interval [95% CI] = 0.59-0.78; P -value ⩽.001), of ever being told they had the hepatitis C virus (HCV; aPR = 0.72; 95% CI: 0.61-0.85; P -value ⩽.001) and a personal history of overdose (aPR = 0.81; 95% CI = 0.73-0.90; P -value ⩽.001). Conclusion: In our study analyzing associations between preferred substance and various behavioral and health outcomes amongst people who use both heroin and methamphetamine, a majority of participants preferred heroin. Methamphetamine preference was associated with lower prevalence of naloxone possession, ever being told they had HCV, and prior history of an overdose. This study underscores the need for targeted harm reduction services for people who prefer methamphetamine in rural areas. [ABSTRACT FROM AUTHOR]

Introduction: To expand access to naloxone, the state of Illinois implemented a standing order allowing registered pharmacies to dispense the drug without an individual prescription. To participate under the standing order, pharmacies were required to opt in through a formal registration process. In our study we aimed to evaluate the availability and price of naloxone at registered pharmacies. Methods: This was a prospective, de-identified, cross-sectional telephone survey. Trained interviewers posed as potential customers and used a standardized script to determine the availability of naloxone between February-December, 2019. The primary outcome was defined as a pharmacy indicating it carried naloxone, currently had naloxone in stock, and was able to dispense it without an individual prescription. Results: Of 948 registered pharmacies, 886 (93.5%) were successfully contacted. Of those, 792 (83.4%) carried naloxone, 659 (74.4%) had naloxone in stock, and 472 (53.3%) allowed purchase without a prescription. Naloxone nasal spray (86.4%) was the formulation most commonly stocked. Chain pharmacies were more likely to carry naloxone (adjusted odds ratio [aOR] 3.16, 95% confidence interval [CI] 1.97-5.01, P < 0.01) and have naloxone in stock (aOR 2.72, 95% CI 1.76-4.20, P < 0.01), but no more likely to dispense it without a prescription. Pharmacies in higher population areas (aOR 0.99, 95% CI 0.99-0.99, P < 0.05) and rural areas adjacent to metropolitan areas (aOR 0.5, 95% CI 025-0.98, P < 0.05) were less likely to have naloxone available without a prescription. Associations of naloxone availability based on other urbanicity designations, overdose count, and overdose rate were not significant. Conclusion: Among pharmacies in Illinois that formally registered to dispense naloxone without a prescription, the availability of naloxone remains limited. Additional interventions may be needed to maximize the potential impact of a statewide standing order. [ABSTRACT FROM AUTHOR]

Issues: To date, there has been no synthesis of research addressing the scale and nuances of the opioid epidemic in racial/ethnic minority populations in the United States that considers the independent and joint impacts of dynamics such as structural disadvantage, provider bias, health literacy, cultural norms and various other risk factors. Approach: Using the "risk environment" framework, we conducted a scoping review on PubMed, Embase and Google Scholar of peer‐reviewed literature and governmental reports published between January 2000 and February 2024 on the nature and scale of opioid use, opioid prescribing patterns, and fatal overdoses among racial/ethnic minorities in the United States, while also examining macro, meso and individual‐level risk factors. Key Findings: Results from this review illuminate a growing, but fragmented, literature lacking standardisation in racial/ethnic classification and case reporting, specifically in regards to Indigenous and Asian subpopulations. This literature broadly illustrates racial/ethnic minorities' increasing nonmedical use of opioids, heightened burdens of fatal overdoses, specifically in relation to polydrug use and synthetic opioids, with notable elevations among Black/Latino subgroups, in addition uneven opioid prescribing patterns. Moreover, the literature implicates a variety of unique risk environments corresponding to dynamics such as residential segregation, provider bias, overpolicing, acculturative stress, patient distrust, and limited access to mental health care services and drug treatment resources, including medications for opioid use disorder. Implications: There has been a lack of rigorous, targeted study on racial/ethnic minorities who use opioids, but evidence highlights burgeoning increases in usage, especially polydrug/synthetic opioid use, and disparities in prescriptions and fatal overdose risk‐phenomena tied to multi‐level forms of entrenched disenfranchisement. Conclusion: There is a need for further research on the complex, overlapping risk environments of racial/ethnic minorities who use opioids, including deeper inclusion of Indigenous and Asian individuals, and efforts to generate greater methodological synergies in population classification and reporting guidelines. [ABSTRACT FROM AUTHOR]

To educate members of the blind, low‐vision and diverse needs communities on the pathogenesis of the chronic autoimmune disease, type 1 diabetes, members of our team with research expertise in immune‐mediated diseases, participated in the 2023 Monash Sensory Science (MSS) Exhibition. Using QR code linked audio commentary, participants were guided through tactile displays demonstrating normal insulin action in the regulation of blood glucose levels and its vital role in providing energy to tissues, followed by displays describing the various stages of the immune system's aberrant attack and the eventual complete destruction of the insulin producing beta‐cells of the pancreatic islets in type 1 diabetes. These models conveyed to the participants the huge effect that this autoimmune‐mediated disease has on the quality of life of affected individuals including the subsequent lifelong reliance on insulin injections to maintain glucose homeostasis. This MSS Exhibition provided a unique opportunity for our researchers to engage with under‐represented members of the community and to raise awareness about such a debilitating and common autoimmune disease. [ABSTRACT FROM AUTHOR]

Background: Accurate prevalence estimates of drug use and its harms are important to characterize burden and develop interventions to reduce negative health outcomes and disparities. Lack of a sampling frame for marginalized/stigmatized populations, including persons who use drugs (PWUD) in rural settings, makes this challenging. Respondent-driven sampling (RDS) is frequently used to recruit PWUD. However, the validity of RDS-generated population-level prevalence estimates relies on assumptions that should be evaluated. Methods: RDS was used to recruit PWUD across seven Rural Opioid Initiative studies between 2018-2020. To evaluate RDS assumptions, we computed recruitment homophily and design effects, generated convergence and bottleneck plots, and tested for recruitment and degree differences. We compared sample proportions with three RDS-adjusted estimators (two variations of RDS-I and RDS-II) for five variables of interest (past 30-day use of heroin, fentanyl, and methamphetamine; past 6-month homelessness; and being positive for hepatitis C virus (HCV) antibody) using linear regression with robust confidence intervals. We compared regression estimates for the associations between HCV positive antibody status and (a) heroin use, (b) fentanyl use, and (c) age using RDS-1 and RDS-II probability weights and no weights using logistic and modified Poisson regression and random-effects meta-analyses. Results: Among 2,842 PWUD, median age was 34 years and 43% were female. Most participants (54%) reported opioids as their drug of choice, however regional differences were present (e.g., methamphetamine range: 4-52%). Many recruitment chains were not long enough to achieve sample equilibrium. Recruitment homophily was present for some variables. Differences with respect to recruitment and degree varied across studies. Prevalence estimates varied only slightly with different RDS weighting approaches, most confidence intervals overlapped. Variations in measures of association varied little based on weighting approach. Conclusions: RDS was a useful recruitment tool for PWUD in rural settings. However, several violations of key RDS assumptions were observed which slightly impacts estimation of proportion although not associations. [ABSTRACT FROM AUTHOR]

People who nonmedically use drugs (PWUD) face intricate social issues that suppress self-actualization, communal integration, and overall health and wellness. "Strengths-based" approaches, an under-used pedagogy and practice in addiction medicine, underscore the significance of identifying and recognizing the inherent and acquired skills, attributes, and capacities of PWUD. A strengths-based approach engenders client affirmation and improves their capacity to reduce drug use-related harms by leveraging existing capabilities. Exploring this paradigm, we conducted and analyzed interviews with 46 PWUD who were clients at syringe services programs in New York City and rural southern Illinois, two areas with elevated rates of opioid-related morbidity and mortality, to assess respondents' perceived strengths. We located two primary thematic modalities in which strengths-based ethos is expressed: individuals (1) being and advocate and resource for harm reduction knowledge and practices and (2) engaging in acts of continuous self-actualization. These dynamics demonstrate PWUD strengths populating and manifesting in complex ways that both affirm and challenge humanist and biomedical notions of individual agency, as PWUD refract enacted, anticipated, and perceived stigmas. In conclusion, programs that blend evidence-based, systems-level interventions on drug use stigma and disenfranchisement with meso and micro-level strengths-based interventions that affirm and leverage personal identity, decision-making capacity, and endemic knowledge may help disrupt health promotion cleavages among PWUD. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to examine the impact of firm environmental, social and governance (ESG) rating scores on market perception and stock behavior from 2017 to 2021 while controlling for COVID-19 severity score. Design/methodology/approach: The authors used panel regression models with robust standard errors based on cross-country and cross-industry sample of 1,324 ESG firms from 25 emerging countries across four regions. Four separate regression analyses are used. Hausman test is used to determine whether fixed-effect (FE) or random-effect approaches should be used in regression models. Lagrange multiplier test is used to test for time FEs, and F-test for individual effects to choose between pooled ordinary least squares model and FE. Two-unit root tests are conducted to check stationarity. Heteroskedasticity and serial correlation were controlled through a robust covariance matrix estimation. Findings: The authors provide evidence that the stakeholder theory persists in emerging countries. Overall, the results suggest that firms' stock behavior is positively associated with the level of environmental and social performance in the region. However, the results do not provide empirical evidence to support the link between ESG performance and stock market perception proxied by the price-to-sales ratio. The results suggest that Refinitiv and Bloomberg ESG rating scores have a positive impact on stock performance in emerging markets, albeit the Bloomberg rating score is insignificant. Practical implications: Favorable impact of environmental and social performance on stock performance suggests that policymakers should take initiatives to raise awareness toward investments in ESG projects. Evidence shows that ESG stock performance in emerging markets does not insulate firms from the COVID-19 severity. Furthermore, this study highlights the inconsistency in calculating the ESG ratings, therefore, a more standardized approach is recommended to support investors seeking sustainable investments. Social implications: The findings have social implications for investors with proenvironmental preferences and nonpecuniary motives for ethical investments. Asset fund managers should develop ESG investment strategies to promote investor preferences that are linked to the proenvironmental and prosocial attitudes by increasing their investments in stocks of firms that behave ethically and support the environment. Furthermore, the findings show that investors pay a price for ethical and socially responsible investments as they are evaluating the environmental and social activities, hence, the firm ESG profile influences equity valuation and risk assessment. Originality/value: The study extends the literature and provides evidence from the unique setting of emerging markets by analyzing the relationship between ESG rating scores and the COVID-19 severity scores on one hand, and stock behavior and market perception on the other. [ABSTRACT FROM AUTHOR]

The significant biological and functional differences between small and large platelets suggested by recent studies could have profound implications for transfusion medicine. However, investigating the relationship between platelet size and function is challenging because separating platelets by size without affecting their properties is difficult. A standard approach is centrifugation, but it inevitably leads to premature activation and aggregation of separated platelets. This paper describes the development and validation of a microfluidic device based on controlled incremental filtration (CIF) for separating platelets by size without the cell damage and usability limitations associated with centrifugation. Platelet samples derived from whole blood were used to evaluate the dependence of the CIF device separation performance on design parameters and flow rate, and to compare the properties of PLT fractions generated by the CIF device with those produced using a centrifugation protocol in a split-sample study. This was accomplished by quantifying the platelet size distribution, mean platelet volume (MPV), platelet-large cell ratio (P-LCR) and platelet activation before and after processing for all input and output samples. The 'large platelet' fractions produced by the CIF device and the centrifugation protocol were essentially equivalent (no significant difference in MPV and P-LCR). Platelets in the 'small platelet' fraction produced by the CIF device were significantly smaller than those produced by centrifugation (lower MPV and P-LCR). This was because the CIF 'small platelet' fraction was contaminated by much fewer large platelets (∼2-times lower recovery of >12 fL platelets) and retained the smallest platelets that were discarded by the centrifugation protocol. There was no significant difference in platelet activation between the two methods. However, centrifugation required a substantial amount of additional anticoagulant to prevent platelet aggregation during pelleting. Unlike centrifugation, the CIF device offered continuous, flow-through, single-step processing that did not cause platelet aggregation. Such a capability has the potential to accelerate the basic studies of the relationship between platelet size and function, and ultimately improve transfusion practice, particularly in the pediatric setting, where the need for low-volume, high-quality platelet transfusions is most urgent. [ABSTRACT FROM AUTHOR]

The majority of adoptive cellular therapies are produced from peripheral mononuclear cells obtained via leukapheresis and further enriched for the cells of interest (e.g., T cells). Here, we present a first‐of‐its‐kind closed system, which effectively removes ~85% of monocytes and ~88% of platelets, while recovering ~88% of concentrated T cells in a separate output stream, as the leukapheresis sample flows through a microfluidic device at 5 mL/min. The system is driven by a common peristaltic pump, enabled by a novel pressure wave dampener, and operates in a closed bag‐to‐bag configuration, without requiring any specialized, dedicated equipment. When compared to standard density gradient centrifugation on paired samples, the new system demonstrated a 1.5‐fold increase in T cell recovery and a 2‐fold reduction in inter‐sample variability for this separation outcome. The T cell‐to‐monocyte ratio of the leukapheresis sample was increased to 20:1, whereas with density gradient processing it decreased to 2:1. As a result of superior purity and/or gentler processing, T cells enriched by the system showed a 2.7‐times higher fold expansion during subsequent culture, and an overall 3.5‐times higher cumulative yield. This centrifugation‐free and label‐free closed system for enriching lymphocytes could significantly simplify and standardize the manufacturing of life‐saving cellular therapies. [ABSTRACT FROM AUTHOR]

Tetrodotoxin analogues (TTXs) used in research and development were originated from biological sources for the last decades. Among TTXs‐bearing aquatic animals, horseshoe crab Carcinoscorpius rotundicauda from Vietnam's Coast was reported to contain a high level of TTXs, indicating a promising source for extraction and purification of TTXs. In this work, horseshoe crab C. rotundicauda collected from Can Gio Coast, Vietnam was used for TTX extraction using homogenization‐assisted method with acetic acid solvent. The extraction process was analysed and optimized by single‐factor investigation and response surface methodology (RSM). Single‐factor investigation pointed out that the optimal conditions for TTX recovery yield from C. rotundicauda's soft tissues were homogenization time of 20 min, acetic acid concentration of 1.0%, solvent/matrix ratio of 4 mL/g, extraction temperature of 70°C, extraction time of 30 min and number of extraction of two times. The most significant factors including acetic acid concentration, solvent/matrix ratio and extraction temperature were utilized for constructing the RSM model to predict TTX recovery yield. The maximal TTX recovery yield predicted from RSM model was 97.3% under solvent/matrix ratio of 4 mL/g, extraction temperature of 70°C and acetic acid concentration of 1% (v/v). The RSM model displayed a high stability and precision for prediction of TTX recovery yield from experiments of 1–10 kg C. rotundicauda's soft tissues/batch extractions producing low errors (−1.95% to 1.85%). TTXs in C. rotundicauda's soft tissues were elucidated by HPLC‐MS/MS, revealing the presence of three analogues TTX, 4epi‐TTX and Anh‐TTX with their contents of 43.02, 22.54 and 45.07 μg/g, respectively. [ABSTRACT FROM AUTHOR]

A photoemission electron microscope (PEEM) was recently commissioned at the NIST. To benchmark its capabilities, epitaxial graphene on 4H-SiC (0001) was imaged and analyzed in the PEEM and compared to other complementary imaging techniques. We determine our routine spatial resolution to be about 50 nm. Using the well-known electronic structure of graphene as a reference, we outline a procedure to calibrate our instrument in energy and momenta in the micrometer-angle-resolved photoemission spectroscopy (μ-ARPES). We also determine the energy and momenta resolution to be about 300 meV, 0.08 Å−1 (ky), and 0.2 Å−1 (kx), respectively. We identify distinct regions of the graphene surface based on intensity contrast rising from topographic and electronic contrasts as well as μ-ARPES. These regions are one layer graphene, one SiC buffer layer, and ≥2 layers of graphene (or graphite). These assignments are confirmed using confocal laser scanning microscopy and Raman spectroscopy. Finally, the PEEM instrument had enough sensitivity to observe the flatband in monolayer epitaxial graphene, which we attribute to the presence of compressive strain, −1.2%, in the graphene sample. [ABSTRACT FROM AUTHOR]

Some qualitative studies have mentioned the impact of trading networks on the credit levels of countries or businesses. However, only a few studies quantified network information on simulated or actual data. This research studied the relationship between network characteristics and sovereign credit levels. Using a data set for 114 countries, we developed and compared the performance of five credit classification models with and without integrating network information. We used several measures to quantify the trading network information, such as Trading Weight, Closeness, Betweenness, PageRank, and Modularity. The analysis showed that they were closely related to credit levels. In particular, the Trading Weight usually belonged to the top five critical features for almost all classifiers. Overall, we saw that the correct prediction of the network models was consistently higher than those without a network. It meant we could improve the sovereign credit classifications with available trading network information. [ABSTRACT FROM AUTHOR]

Parahydrogen‐induced polarization (PHIP) followed by polarization transfer to 13C is a rapidly developing technique for the generation of 13C‐hyperpolarized substrates. Chirality plays an essential role in living systems and differential metabolism of enantiomeric pairs of metabolic substrates is well documented. Inspired by asymmetric hydrogenation, here we report stereoPHIP, which involves the addition of parahydrogen to a prochiral substrate with a chiral catalyst followed by polarization transfer to 13C spins. We demonstrate that parahydrogen could be rapidly added to the prochiral precursor to both enantiomers of lactic acid (D and L), with both the (R,R) and (S,S) enantiomers of a chiral rhodium(I) catalyst to afford highly 13C‐hyperpolarized (over 20 %) L‐ and D‐lactate ester derivatives, respectively, with excellent stereoselectivity. We also show that the hyperpolarized 1H signal decays obtained with the (R,R) and (S,S) catalysts were markedly different. StereoPHIP expands the scope of conventional PHIP to the production of 13C hyperpolarized chiral substrates with high stereoselectivity. [ABSTRACT FROM AUTHOR]

Parahydrogen‐induced polarization (PHIP) followed by polarization transfer to 13C is a rapidly developing technique for the generation of 13C‐hyperpolarized substrates. Chirality plays an essential role in living systems and differential metabolism of enantiomeric pairs of metabolic substrates is well documented. Inspired by asymmetric hydrogenation, here we report stereoPHIP, which involves the addition of parahydrogen to a prochiral substrate with a chiral catalyst followed by polarization transfer to 13C spins. We demonstrate that parahydrogen could be rapidly added to the prochiral precursor to both enantiomers of lactic acid (D and L), with both the (R,R) and (S,S) enantiomers of a chiral rhodium(I) catalyst to afford highly 13C‐hyperpolarized (over 20 %) L‐ and D‐lactate ester derivatives, respectively, with excellent stereoselectivity. We also show that the hyperpolarized 1H signal decays obtained with the (R,R) and (S,S) catalysts were markedly different. StereoPHIP expands the scope of conventional PHIP to the production of 13C hyperpolarized chiral substrates with high stereoselectivity. [ABSTRACT FROM AUTHOR]

Background: Research conducted in urban areas has highlighted the impact of housing instability on people who inject drugs (PWID), revealing that it exacerbates vulnerability to drug-related harms and impedes syringe service program (SSP) use. However, few studies have explored the effects of houselessness on SSP use among rural PWID. This study examines the relationship between houselessness and SSP utilization among PWID in eight rural areas across 10 states. Methods: PWID were recruited using respondent-driven sampling for a cross-sectional survey that queried self-reported drug use and SSP utilization in the prior 30 days, houselessness in the prior 6 months and sociodemographic characteristics. Using binomial logistic regression, we examined the relationship between experiencing houselessness and any SSP use. To assess the relationship between houselessness and the frequency of SSP use, we conducted multinomial logistic regression analyses among participants reporting any past 30-day SSP use. Results: Among 2394 rural PWID, 56.5% had experienced houselessness in the prior 6 months, and 43.5% reported past 30-day SSP use. PWID who had experienced houselessness were more likely to report using an SSP compared to their housed counterparts (adjusted odds ratio [aOR] = 1.24 [95% confidence intervals [CI] 1.01, 1.52]). Among those who had used an SSP at least once (n = 972), those who experienced houselessness were just as likely to report SSP use two (aOR = 0.90 [95% CI 0.60, 1.36]) and three times (aOR = 1.18 [95% CI 0.77, 1.98]) compared to once. However, they were less likely to visit an SSP four or more times compared to once in the prior 30 days (aOR = 0.59 [95% CI 0.40, 0.85]). Conclusion: This study provides evidence that rural PWID who experience houselessness utilize SSPs at similar or higher rates as their housed counterparts. However, housing instability may pose barriers to more frequent SSP use. These findings are significant as people who experience houselessness are at increased risk for drug-related harms and encounter additional challenges when attempting to access SSPs. [ABSTRACT FROM AUTHOR]

To compare the rate of positive thyroid peroxidase antibodies (TPO Ab) between women with different polycystic ovary syndrome (PCOS) phenotypes and women without PCOS. This is a retrospective cohort study. Women with PCOS at My Duc Hospital between June 1, 2020, and March 27, 2021, were matched with non-PCOS women by age. TPO Ab (cut-off: 34 IU/mL) and thyroid-stimulating hormone (TSH) levels were measured as markers of Hashimoto thyroiditis and thyroid function, respectively. One thousand eight hundred eight infertile women were included, 904 with PCOS (mean age 29.0 ± 3.58 years) and 904 without PCOS (29.1 ± 3.4 years; controls). Women with PCOS had a higher body mass index (22.8 ± 3.84 vs. 19.9 ± 2.23 kg/m2, p < 0.001), but most were not overweight/obese. Rates of positive TPO Ab in women with versus without PCOS were 8.2% and 8.4%, respectively (p = 0.932). Rates of positive TPO Ab in patients with PCOS phenotype A, B, C, or D were not statistically different (7.5%, 2.9%, 20.0%, and 7.8%, respectively). Median TSH concentrations were similar in the PCOS and control groups (1.84 mIU/L vs. 1.78 mIU/L, respectively; p = 0.194). Based on a linear regression model, there was no correlation between either BMI or the estradiol to progesterone ratio and TPO Ab status. In a large population of infertile women with PCOS who were mostly lean patients, rates of positive TPO Ab across all four PCOS phenotypes did not differ significantly from those in women without PCOS. These findings did not support the hypothesis that PCOS is a risk factor for Hashimoto thyroiditis. [ABSTRACT FROM AUTHOR]

Tissue engineering has driven significant research in the strive to create a supply of tissues for patient treatment. Cell integration into engineered tissues maximizes functional capabilities, however, issues of rejection remain. Autologous cell sources able to solve this issue are difficult to identify for tissue engineering purposes. Here, we present the efficacy of patient-sourced cells derived from adipose (adipose-derived stem cells, ASCs) and skin tissue (dermal fibroblasts, PtFibs) to build a combined engineered tunica media and adventitia graft, respectively. Patient cells were integrated into our lab's vascular tissue engineering technique of forming vascular rings that are stacked into a tubular structure to create the vascular graft. For the media layer, ASCs were successfully differentiated into the smooth muscle phenotype using angiotensin II followed by culture in smooth muscle growth factors, evidenced by significantly increased expression of αSMA and myosin light chain kinase. Engineered media vessels composed of differentiated ASCs (ASC-SMCs) exhibited an elastic modulus (45.2 ± 18.9 kPa) between that of vessels of undifferentiated ASCs (71.8 ± 35.3 kPa) and control human aortic smooth muscle cells (HASMCs; 18.7 ± 5.49 kPa) (p<0.5). Tensile strength of vessels composed of ASCs (41.3 ± 15.7 kPa) and ASC-SMCs (37.3 ± 17.0 kPa) were higher compared to vessels of HASMCs (28.4 ± 11.2 kPa). ASC-based tissues exhibited a significant increase in collagen content and fiber maturity- both factors contribute to tissue strength and stability. Furthermore, vessels gained stability and a more-uniform single-tubular shape with longer-term 1-month culture. This work demonstrates efficacy of ASCs and PtFibs to create patient-specific vessels. [ABSTRACT FROM AUTHOR]

In use of clayey soils for reclamation, the stability against slip and future consolidation settlement should be examined during and after reclamation. For these purposes, a practical reclamation management system has been developed based on three types of analysis: artificial intelligence (AI) estimation of soil properties such as compression index, consolidation coefficient and undrained shear strength, deposition shape analysis; and consolidation settlement analysis for clayey soils dumped from a hopper barge. The AI estimation of soil properties is characterized by use of a convolutional neural network (CNN) based on information such as soil source, wet density, and photographed image obtained before reclamation works. In this study, the validity of each analysis model has been verified on an actual reclamation project by use of measured data such as deposition shape of dumped soils on the seabed, soil properties in the reclaimed ground and consolidation settlement after reclamation and soil improvement. [ABSTRACT FROM AUTHOR]

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Tissue engineering has the advantage of replicating soft tissue mechanics to better simulate and integrate into native soft tissue. However, soft tissue engineering has been fraught with issues of insufficient tissue strength to withstand physiological mechanical requirements. This factor is due to the lack of strength inherent in cell-only constructs and in the biomaterials used for soft tissue engineering and limited extracellular matrix (ECM) production possible in cell culture. To address this issue, we explored the use of an ECM-based hydrogel coating to serve as an adhesive tool, as demonstrated in vascular tissue engineering. The efficacy of cells to supplement mechanical strength in the coating was explored. Specifically, selected coatings were applied to an engineered artery tunica adventitia to accurately test their properties in a natural tissue support structure. Multiple iterations of three primary hydrogels with and without cells were tested: fibrin, collagen, and gelatin hydrogels with and without fibroblasts. The effectiveness of a natural crosslinker to further stabilize and strengthen the hydrogels was investigated, namely genipin extracted from the gardenia fruit. We found that gelatin crosslinked with genipin alone exhibited the highest tensile strength; however, fibrin gel supported cell viability the most. Overall, fibrin gel coating without genipin was deemed optimal for its balance in increasing mechanical strength while still supporting cell viability and was used in the final mechanical and hydrodynamic testing assessments. Engineered vessels coated in fibrin hydrogel with cells resulted in the highest tensile strength of all hydrogel-coated groups after 14 d in culture, demonstrating a tensile strength of 11.9 ± 2.91 kPa, compared to 5.67 ± 1.37 kPa for the next highest collagen hydrogel group. The effect of the fibrin hydrogel coating on burst pressure was tested on our strongest vessels composed of human aortic smooth muscle cells. A significant increase from our previously reported burst pressure of 51.3 ± 2.19 mmHg to 229 ± 23.8 mmHg was observed; however, more work is needed to render these vessels compliant with mechanical and biological criteria for blood vessel substitutes. [ABSTRACT FROM AUTHOR]

This work focused on synthesising Ni-doped LiNixFe1−xPO4/C (x = 0, 0.05 and 0.1) cathode materials by hydrothermal method. The crystalline structure and morphology of the synthesised materials were investigated through x-ray diffraction, Raman scattering spectroscopy, thermal gravimetric analysis, and scanning electron microscopy. Their electrochemical performance was analysed by cyclic voltammetry and galvanostatic cycling test. The highest initial capacity of 170.3 mAh/g was achieved for LiNi0.1Fe0.9PO4/C. It also maintained 99.68% of its initial capacity for 120 cycles, with a Li+-ion diffusion coefficient of 1.12 × 10−12 cm2/s compared with that (9.21 × 10−13 cm2/s) of LiNi0.05Fe0.95PO4/C. [ABSTRACT FROM AUTHOR]

Unmanned aerial vehicles (UAVs) are considered to play vital roles in the Sixth Generation (6G) networks and beyond. However, the confidentiality of UAV communication is sensitive to security threats owing to the broadcast nature and principal line-of-sight channel conditions. This paper proposes a three-dimensional (3D) robust beamforming method for UAV systems in terms of physical layer security in order to improve secrecy performance. In particular, attempting to maximize the average secrecy rate (ASR) of the considered system, a precisely designed unsupervised artificial neural network based on Denoising AutoEncoder (DAE) is used to optimize the beamformer for confidential signal with the simultaneous existence of artificial noise (AN). Simulation results show that the proposed approach can achieve higher average secrecy and more focused beams than existing previous methods in the same scenarios. [ABSTRACT FROM AUTHOR]

Chromolaena odorata (C. odorata) (L.) R. King & H. Robinson is a perennial flowering shrub with diverse habitats, including crops, grasslands, and roadsides. This plant has been widely used in Vietnamese folk medicine for gastric ulcer treatment. Hence, the present study aimed to evaluate the acute toxicity and the anti-ulcer effect of the ethanol crude extract of C. odorata leaves and its fractions against the indomethacin-induced gastric ulcer model in mice, and investigate the chemical constituents of the most active fraction. According to in vivo results, the ethyl acetate residue with the highest anti-ulcer activity significantly reduced gastric lesions in the experimental mice model with an ulcer index of 0.73 ± 0.39 and a percentage inhibition of 26.92%. Thus, this fraction was chosen for further chemical investigation. Four pure compounds (1-4) were extracted and isolated by using chromatographic methods. Based on the nuclear magnetic resonance spectroscopy, melting temperature, mass spectrometry analysis, and compared with the published literature, their structures were elucidated as 1-(4-hydroxy-3-methoxyphenyl)propane- 1,2-diol (1), kaempferol-7-O-α-L-rhamnopyranoside (2), naringenin-5,7-di-O-β-Dglucopyranoside (3), and rubrosterone (4). To our best knowledge, all of these compounds were isolated for the first time from C. odorata leaves. These findings contribute to providing scientific evidence for the traditional use and phytochemicals of C. odorata leaves. [ABSTRACT FROM AUTHOR]

The isolation of a specific lymphocyte subset from blood is the required first step in the manufacturing of many novel cellular immunotherapies. Microfluidic size-based separation methods are poised to significantly simplify this process because they require neither centrifugation nor magnetic or fluorescent labeling to operate. Lymphocytes can be separated from red blood cells (RBCs) and platelets as well as monocytes and granulocytes because their size differs from each of these cell types. However, further separation of a specific lymphocyte subset from other unwanted lymphocytes using size-based methods is impossible because all lymphocytes have approximately the same size and can only be distinguished by surface markers. This paper describes a new approach that made it possible for a size-based separation method to isolate a desired subset of lymphocytes by making unwanted lymphocytes as well as other blood cells artificially larger. The separation was enabled by selectively binding multiple RBCs to each unwanted cell to create 'rosettes' with an effective size significantly larger than the diameter of a typical lymphocyte. The desired lymphocytes remained unaffected by rosetting and were separated from the rosettes by passing the mixture through a microfluidic size-based separation device based on controlled incremental filtration (CIF). This new rosette-enabled size-based (RESIZE) separation approach demonstrated recovery of 80–90% for all lymphocyte subsets tested (CD3+, CD4+, CD56+) which was ∼2.5-fold higher than that for the standard immunodensity method (RBC rosetting followed by density gradient centrifugation). The purity of separation was >90% for CD3+ cells but declined with increasing cell rarity. Unlike the immunodensity approach, RESIZE required neither centrifugation nor cell washing after the separation and was ∼2.5-fold faster when processing the same sample volume. The results of this study suggest that integration of the RESIZE approach for high-yield isolation of lymphocyte subsets from blood could significantly streamline the manufacturing workflow and thus have a potentially transformative impact on the cost and availability of novel cellular immunotherapies. [ABSTRACT FROM AUTHOR]

Quantification of heritability is a fundamental desideratum in genetics, which allows an assessment of the contribution of additive genetic variation to the variability of a trait of interest. The traditional computational approaches for assessing the heritability of a trait have been developed in the field of quantitative genetics. However, the rise of modern population genomics with large sample sizes has led to the development of several new machine learning-based approaches to inferring heritability. In this article, we systematically summarize recent advances in machine learning which can be used to infer heritability. We focus on an application of these methods to bacterial genomes, where heritability plays a key role in understanding phenotypes such as antibiotic resistance and virulence, which are particularly important due to the rising frequency of antimicrobial resistance. By designing a heritability model incorporating realistic patterns of genome-wide linkage disequilibrium for a frequently recombining bacterial pathogen, we test the performance of a wide spectrum of different inference methods, including also GCTA. In addition to the synthetic data benchmark, we present a comparison of the methods for antibiotic resistance traits for multiple bacterial pathogens. Insights from the benchmarking and real data analyses indicate a highly variable performance of the different methods and suggest that heritability inference would likely benefit from tailoring of the methods to the specific genetic architecture of the target organism. Availability and implementation The R codes and data used in the numerical experiments are available at: https://github.com/tienmt/her_MLs. [ABSTRACT FROM AUTHOR]

Objective: To examine the association between adherence to plant-based diets and mortality. Design: Prospective study. We calculated a plant-based diet index (PDI) by assigning positive scores to plant foods and reverse scores to animal foods. We also created a healthful PDI (hPDI) and an unhealthful PDI (uPDI) by further separating the healthy plant foods from less-healthy plant foods. Setting: The VA Million Veteran Program. Participants: 315 919 men and women aged 19–104 years who completed a FFQ at the baseline. Results: We documented 31 136 deaths during the follow-up. A higher PDI was significantly associated with lower total mortality (hazard ratio (HR) comparing extreme deciles = 0·75, 95 % CI: 0·71, 0·79, P trend < 0·001]. We observed an inverse association between hPDI and total mortality (HR comparing extreme deciles = 0·64, 95 % CI: 0·61, 0·68, P trend < 0·001), whereas uPDI was positively associated with total mortality (HR comparing extreme deciles = 1·41, 95 % CI: 1·33, 1·49, P trend < 0·001). Similar significant associations of PDI, hPDI and uPDI were also observed for CVD and cancer mortality. The associations between the PDI and total mortality were consistent among African and European American participants, and participants free from CVD and cancer and those who were diagnosed with major chronic disease at baseline. Conclusions: A greater adherence to a plant-based diet was associated with substantially lower total mortality in this large population of veterans. These findings support recommending plant-rich dietary patterns for the prevention of major chronic diseases. [ABSTRACT FROM AUTHOR]

Additionally, as MVP expands eligibility to Veterans who may not use the VA for health care services, the importance of self-report data becomes imperative as MVP builds the infrastructure to access external health records. For greater applicability, it is envisioned that the MVP Baseline and MVP Lifestyle Surveys will be validated in future MVP scientific projects to enhance the understanding of Veteran health and wellbeing. Data resource access As described in detail in Gaziano's MVP introduction paper[3] and MVP website [https://www.research.va.gov/mvp/], access to MVP data and/or samples is governed by the scope of MVP informed consent and VA policies and requires scientific review by appropriate VA review committees. Keywords: Health surveys; Veteran health; cohort studies; survey development; Veteran lifestyle EN Health surveys Veteran health cohort studies survey development Veteran lifestyle e1 e17 17 02/16/23 20230201 NES 230201 Key Features The Department of Veterans Affairs (VA) Million Veteran Program (MVP) is a national voluntary research programme designed to examine genetic influences on health with the goal of improving health for Veterans. [Extracted from the article]

Breast and gynaecological cancer (BGC) patients receiving chemotherapy may experience high levels of stress during the COVID-19 pandemic. Music interventions may be effective in lowering their stress levels. This study explored stressors, coping strategies, and the feasibility of music interventions among BGC patients in Vietnam. An exploratory qualitative study with individual face-to-face semi-structured interviews was conducted. A convenience sample of BGC patients receiving chemotherapy was recruited from the oncology centre of a public hospital in Vietnam. Twenty patients were interviewed with open-ended questions developed based on the transactional model of stress and coping to explore stress-causing factors and coping strategies and based on guidelines for music therapy practice to explore their music preferences and perceptions. Field notes and interview transcripts were analysed following the qualitative content analysis approach. Two stressor themes were identified: undesirable experiences during treatment and patients' inability to fulfil their own roles and responsibilities. Our findings revealed a new coping strategy—self-realisation of responsibilities towards the family—that is not listed in the transactional model of stress and coping. Future psychological interventions for stress management among BGC patients should focus on raising the patients' awareness of their values and responsibilities towards their families. Three categories of preferred music genres for stress reduction were identified: religious, softly melodic, and revolutionary music. The patients were aware of the positive effects of music and had different musical preferences. This study also explored the acceptance of music interventions and facilitators and barriers to implementing them among BGC patients in Vietnam. The findings suggest that before implementing music interventions, the musical preferences, religions, and beliefs of each individual should be considered to achieve desirable results. Music interventions for BGC patients receiving chemotherapy in Vietnam are feasible. Further intervention studies are needed to evaluate their effectiveness. [ABSTRACT FROM AUTHOR]

Elevated body mass index (BMI) is heritable and associated with many health conditions that impact morbidity and mortality. The study of the genetic association of BMI across a broad range of common disease conditions offers the opportunity to extend current knowledge regarding the breadth and depth of adiposity-related diseases. We identify 906 (364 novel) and 41 (6 novel) genome-wide significant loci for BMI among participants of European (N~1.1 million) and African (N~100,000) ancestry, respectively. Using a BMI genetic risk score including 2446 variants, 316 diagnoses are associated in the Million Veteran Program, with 96.5% showing increased risk. A co-morbidity network analysis reveals seven disease communities containing multiple interconnected diseases associated with BMI as well as extensive connections across communities. Mendelian randomization analysis confirms numerous phenotypes across a breadth of organ systems, including conditions of the circulatory (heart failure, ischemic heart disease, atrial fibrillation), genitourinary (chronic renal failure), respiratory (respiratory failure, asthma), musculoskeletal and dermatologic systems that are deeply interconnected within and across the disease communities. This work shows that the complex genetic architecture of BMI associates with a broad range of major health conditions, supporting the need for comprehensive approaches to prevent and treat obesity. Elevated body mass index is heritable and associated with many health conditions that impact morbidity and mortality. Here, the authors identify greater than 900 genetic loci for body mass index (BMI) and find over 300 diagnoses associated with increasing BMI. [ABSTRACT FROM AUTHOR]

In this retrospective cohort study of 94 595 severe acute respiratory syndrome coronavirus 2–positive cases, we developed and validated an algorithm to assess the association between coronavirus disease 2019 (COVID-19) severity and long-term complications (stroke, myocardial infarction, pulmonary embolism/deep vein thrombosis, heart failure, and mortality). COVID-19 severity was associated with a greater risk of experiencing a long-term complication 31–120 days postinfection. Most incident events occurred 31–60 days postinfection and diminished after day 91, except heart failure for severe patients and death for moderate patients, which peaked on days 91–120. Understanding the differential impact of COVID-19 severity on long-term events provides insight into possible intervention modalities and critical prevention strategies. [ABSTRACT FROM AUTHOR]

Three newly designed benzene-core photonic crystal fibers (BC-PCFs) can optimize both chromatic dispersion and attenuation characteristics simultaneously for the most efficient application to generate supercontinuum. The nonlinear characteristics of BC-PCFs with the circular lattice (CL), square lattice (SL), and hexagonal lattice (HL) are analyzed numerically to select the optimal PCF. The three optimized structures: #CBF1, #SBF2, and #HBF3 are intended for supercontinuum generation (SCG) in an all-normal dispersion regime. The obtained results demonstrated that although #HBF3 fiber has a larger effective mode area and attenuation than #CBF1, #SBF2 fibers, the dispersion curve of #HBF3 is flattest and closest to the zero-dispersion curve in the wavelength region of 0.8–2.0 µm hence it has the highest efficiency for SCG. These PCFs are capable of coherent octave-wide SCG in the 0.66–1.53 µm, 0.71–1.76 µm, and 0.71–1.82 µm wavelength ranges with low peak power of 0.45 kW and 40 fs pulses coupled to the core. Those fibers are the real objects for the sources of all-fiber supercontinuum, which can be substituted for glass core fibers because the nonlinearity of silica is lower than that of benzene. The proposed remedy can lead to new low-cost all-fiber optical systems. [ABSTRACT FROM AUTHOR]

Background: Chronic health conditions associated with long-term drug use may pose additional risks to people who use drugs (PWUD) when coupled with COVID-19 infection. Despite this, PWUD, especially those living in rural areas, may be less likely to seek out health services. Previous research has highlighted the increased disease burden of COVID-19 among PWUD. Our manuscript supplements this literature by exploring unique attitudes of PWUD living in rural areas toward the pandemic, COVID-19 vaccination, and the role of harm reduction (HR) organizations in raising health awareness among PWUD. Methods: Semi-structured interviews were conducted with 20 PWUD living in rural southern Illinois. Audio recordings were professionally transcribed. A preliminary codebook was created based on interview domains. Two trained coders conducted iterative coding of the transcripts, and new codes were added through line-by-line coding and thematic grouping. Results: Twenty participants (45% female, mean age of 38) completed interviews between June and November 2021. Participants reported negative impacts of the pandemic on mental health, financial wellbeing, and drug quality. However, the health impacts of COVID-19 were often described as less concerning than its impacts on these other aspects of life. Many expressed doubt in the severity of COVID-19 infection. Among the 16 unvaccinated participants who reported receiving most of their information from the internet or word of mouth, uncertainty about vaccine contents and distrust of healthcare and government institutions engendered wariness of the vaccination. Distrust of healthcare providers was related to past stigmatization and judgement, but did not extend to the local HR organization, which was unanimously endorsed as a positive institution. Among participants who did not access services directly from the HR organization, secondary distribution of HR supplies by other PWUD was a universally cited form of health maintenance. Participants expressed interest in low-threshold healthcare, including COVID-19 vaccination, should it be offered in the local HR organization's office and mobile units. Conclusion: COVID-19 and related public health measures have affected this community in numerous ways. Integrating healthcare services into harm reduction infrastructures and mobilizing secondary distributors of supplies may promote greater engagement with vaccination programs and other healthcare services. Trial number: NCT04427202. [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM) tumor cells are found in the perivascular niche microenvironment and are believed to associate closely with the brain microvasculature. However, it is largely unknown how the resident cells of the perivascular niche, such as endothelial cells, pericytes, and astrocytes, influence GBM tumor cell behavior and disease progression. A 3D in vitro model of the brain perivascular niche developed by encapsulating brain‐derived endothelial cells, pericytes, and astrocytes in a gelatin hydrogel is described. It is shown that brain perivascular stromal cells, namely pericytes and astrocytes, contribute to vascular architecture and maturation. Cocultures of patient‐derived GBM tumor cells with brain microvascular cells are used to identify a role for pericytes and astrocytes in establishing a perivascular niche environment that modulates GBM cell invasion, proliferation, and therapeutic response. Engineered models provide unique insight regarding the spatial patterning of GBM cell phenotypes in response to a multicellular model of the perivascular niche. Critically, it is shown that engineered perivascular models provide an important resource to evaluate mechanisms by which intercellular interactions modulate GBM tumor cell behavior, drug response, and provide a framework to consider patient‐specific disease phenotypes. [ABSTRACT FROM AUTHOR]

There has been a steep rise in overdoses and mortality among people who use opioids or who inject drugs (PWUD), including in North America, the United Kingdom, and parts of Eastern Europe, with some of the sharpest increases amassing in rural communities. Currently, the literature lacks a comparative focus on the views and experiences of rural PWUD and professionals who regularly work and interface with them, in terms of their understandings of the rural drug use initiation/relapse trajectory. Considering a renewed sociology of emotions and empathy and the constructs of direct experience (e.g., of personal drug use) versus role‐playing (e.g., envisioning oneself in another's position), we used a modified constant comparison method to analyze interviews conducted with PWUD and professional stakeholders in rural southern Illinois, an opioid overdose hotspot. Findings suggest that rural opioid use is adopted in service of an intricate interplay of sensory, relational, somatic, and psychosocial benefits, with a sharp divergence between PWUD, who express considerable agency in their drug use behaviors, and professionals, who fail to successful role‐play in emphasizing PWUD's limited willpower and "deviant" sociocultural predilection. These dynamics illuminate challenges to advancing nuanced, culturally humble programming to advance public health goals related to the opioid and drug injection epidemic. [ABSTRACT FROM AUTHOR]

In this work, pyridoxine (vitamin B6) was determined by the square wave voltammetry at copper‐poly(1,8‐diaminonaphthalene)/graphene modified glassy carbon electrode. The composite electrodes were fabricated with two steps. First, poly(1,8‐diaminonaphthalene) is electrodeposited onto graphene/glassy carbon electrodes with a potential cycling technique. Then, copper ions are adsorbed onto the poly(1,8‐diaminonaphthalene)/graphene modified glassy carbon electrode due to the immersion of the polymeric modified electrode in an aqueous copper (II) solution. The characterizations of synthesized materials have shown the role of graphene in facilitating the electron transfer and the remarkably electrocatalytic ability of copper for pyridoxine oxidation on the electrode surface. In 0.1 M phosphate buffer solution (pH 7.4), the peak current of square wave voltammograms of pyridoxine increased linearly with their concentration in the ranges between 0.58 and 24.51 μM with the limit of detection of 0.3 μM. The proposed electrodes showed excellent reproducibility and stability. [ABSTRACT FROM AUTHOR]

Ophiocordyceps is a megagenus of entomopathogenic fungi belonging to Ophiocordycipitaceae of Hypocreales, Ascomycota. We report here the morphological and phylogenetic analyses of two Ophiocordyceps species from Bidoup Nui Ba National Park, Lam Dong Province, southern Vietnam. Our data showed that one of our studied Ophiocordyceps is a new intraspecies of O. sphecocephala and another is a new record of O. asiana from Vietnam. [ABSTRACT FROM AUTHOR]

Aims: This study identifies the contribution of leaf matter from individual plant species on water repellency with a focus on the composition of organic compounds and the role of heat in releasing these compounds to soil. Methods: Leaf powder from four plant species (Banksia menziesii, Eucalyptus marginata, Allocasuarina fraseriana, Xanthorrhoea preissii) was mixed with acid-washed sand (AWS) under a range of temperatures and WR measured. Plant chemical composition was characterized by extraction of leaf powder and GC/MS analysis. Results: Increasing concentrations of plant powder mixed with AWS increased WR for three species; whereas for X. preissii there was no WR at any concentration. Heating increased WR for all species over the range of 30 to 120 °C. B. menziesii had the greatest WR, which was associated with the largest diversity of fatty acids and n-alcohols and highest concentration of alkanes, whereas X. preissii with the smallest WR had only C16 alcohol and C16 fatty acids at relatively low concentration. Conclusions: Physically mixing leaf powder with AWS allows the contribution of different plant species on WR to be directly examined. WR appears to be related to differences in the concentrations and diversity of n-alcohols, n-fatty acids, and high n-alkanes in the leaves. The observed temperature effects on WR provide insights into the kinetics of release and dispersal of organic compounds from interstitial material. [ABSTRACT FROM AUTHOR]

We investigate the key predictors that influence the soil organic matter (SOM) content in higher altitude plantations. This is to study the potential of carbon sequestration for recapturing CO2 from the atmosphere, which is an important consideration in mitigating global climate change. This research applied distance-based linear models to evaluate and predict the influence of topography and types of land use on soil carbon storage in the tropical mountainous areas of Central Vietnam. Three predictors plantation, altitude, and slope together explained 73.8% of the SOM variation. We focused on four types of plantations including acacia, rubber tree, cassava plantations, and plantations with rotation system between acacia and cassava. We found that they had different carbon accumulation, which depended on various characteristics of the terrain. The acacia plantation forest stored the highest amount of SOM and was less sensitive to changes in altitude. The soil carbon content in cassava plantations was the lowest, and altered considerably with altitude. SOM content in rubber tree and acacia-cassava rotation plantations were similar to each other. Altitude was the most critical driver in affecting the capacity of soil carbon sequestration in each plantation. In higher elevation zones, soil carbon stock was greater, which was probably related to decreasing decomposability by microorganism, and increasing carbon content in foliage and leaf litter. The carbon retention tended to increase gradually over an elevation range of 133–300 m a.s.l. The effects of the terrain slope were observed, when considering certain types of land use, and ones with small altitude disparity. In the slope range of 0° to 20°, the carbon pool showed a tendency to increase its capacity. Higher slope gradients, however, could hinder carbon retention due to organic material loss through erosion. In particular, when the slope was above 30°, the soil organic matter content decreased substantially. [ABSTRACT FROM AUTHOR]

Bioactivity-guided isolation of the CHCl3-soluble fraction of the stems of Salacia chinensis L. (Celastraceae) was carried out to obtain a new 7′,9-epoxylignan (1) and three 7,9′:7′,9-diepoxylignans (2–4). The absolute configuration of 1 was elucidated based on NMR and ECD spectroscopic data interpretation. All isolated lignans showed intermediate α-glucosidase inhibitory activity with the IC50 values ranging from 28.5 to 85.6 µM. [ABSTRACT FROM AUTHOR]