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The hydrothermal synthesis behavior of ZnO nanowire (NW) on carbon nanotubes (CNTs) with respect to molar concentrations of zinc nitrate hexahydrate and hexamethylenetetramine and temperature was investigated. The ZnO NWs could be synthesized with a single-crystalline wurtzite structure and a diameter in the range of tens of nanometers. Their size does not strongly depend on the temperature, while it increases with increasing molar concentration. The NWs tend to have pyramidal shape at a growth front with increasing temperature and molar concentration probably due to enriched Zn2+ ion concentration. This demonstrates the morphological dependence of ZnO NWs on the relative rates between the decomposition of Zn precursor and subsequent oxidation of Zn to ZnO in hydrothermal synthesis. [ABSTRACT FROM AUTHOR]

ABSTRACT Clusters of similar or dissimilar objects are encountered in many fields. Frequently used approaches treat each cluster's central object as latent. Yet, often objects of one or more types cluster around objects of another type. Such arrangements are common in biomedical images of cells, in which nearby cell types likely interact. Quantifying spatial relationships may elucidate biological mechanisms. Parent‐offspring statistical frameworks can be usefully applied even when central objects (“parents”) differ from peripheral ones (“offspring”). We propose the novel multivariate cluster point process (MCPP) to quantify multi‐object (e.g., multi‐cellular) arrangements. Unlike commonly used approaches, the MCPP exploits locations of the central parent object in clusters. It accounts for possibly multilayered, multivariate clustering. The model formulation requires specification of which object types function as cluster centers and which reside peripherally. If such information is unknown, the relative roles of object types may be explored by comparing fit of different models via the deviance information criterion (DIC). In simulated data, we compared a series of models' DIC; the MCPP correctly identified simulated relationships. It also produced more accurate and precise parameter estimates than the classical univariate Neyman–Scott process model. We also used the MCPP to quantify proposed configurations and explore new ones in human dental plaque biofilm image data. MCPP models quantified simultaneous clustering of Streptococcus and Porphyromonas around Corynebacterium and of Pasteurellaceae around Streptococcus and successfully captured hypothesized structures for all taxa. Further exploration suggested the presence of clustering between Fusobacterium and Leptotrichia, a previously unreported relationship. [ABSTRACT FROM AUTHOR]

We designed and synthesized a series of sulfonated poly(arylene ether sulfone) (SPES) with different hydrophilic or hydrophobic oligomer ratios using poly-condensation strategy. Afterward, we fabricated the corresponding membranes via a solution-casting approach. We verified the SPES membrane chemical structure using nuclear magnetic resonance (1H NMR) and confirmed the resulting oligomer ratio. Field-emission scanning electron microscope (FE-SEM) and atomic force microscope (AFM) results revealed that we effectively attained phase separation of the SPES membrane along with an increased hydrophilic oligomer ratio. Thermal stability, glass transition temperature (Tg) and membrane elongation increased with the ratio of hydrophilic oligomers. SPES membranes with higher hydrophilic oligomer ratios exhibited superior water uptake, ion-exchange capacity, contact angle and water sorption, while retaining reasonable swelling degree. The proton conductivity results showed that SPES containing higher amounts of hydrophilic oligomers provided a 74.7 mS cm−1 proton conductivity at 90 °C, which is better than other SPES membranes, but slightly lower than that of Nafion-117 membrane. When integrating SPES membranes with proton-exchange membrane fuel cells (PEMFCs) at 60 °C and 80% relative humidity (RH), the PEMFC power density exhibited a similar increment-pattern like proton conductivity pattern. [ABSTRACT FROM AUTHOR]

A series of anion exchange membranes composed of partially fluorinated poly(arylene ether sulfone)s (PAESs) multiblock copolymers bearing quaternary ammonium groups were synthesized with controlled lengths of the hydrophilic precursor and hydrophobic oligomer via direct polycondensation. The chloromethylation and quaternization proceeded well by optimizing the reaction conditions to improve hydroxide conductivity and physical stability, and the fabricated membranes were very flexible and transparent. Atomic force microscope images of quaternized PAES (QN-PAES) membranes showed excellent hydrophilic/hydrophobic phase separation and distinct ion transition channels. An extended architecture of phase separation was observed by increasing the hydrophilic oligomer length, which resulted in significant improvements in the water uptake, ion exchange capacity, and hydroxide conductivity. Furthermore, the open circuit voltage (OCV) of QN-PAES X10Y23 and X10Y13 was found to be above 0.9 V, and the maximum power density of QN-PAES X10Y13 was 131.7 mW cm−2 at 60 °C under 100% RH. [ABSTRACT FROM AUTHOR]

Sulfonated poly(arylene biphenylether sulfone)-poly(arylene ether) (SPABES-PAE) block copolymers by controlling the molar ratio of SPABES and PAE oligomers were successfully synthesized, and the performances of SPABES-PAE (1:2, 1:1, and 2:1) membranes were compared with Nafion 212. The prepared membranes including fluorinated hydrophobic units were stable against heat, nucleophile attack, and physio-chemical durability during the tests. Moreover, the polymers exhibited better solubility in a variety of solvents. The chemical structure of SPABES-PAEs was investigated by 1H nuclear magnetic resonance (1H NMR), Fourier transform infrared spectroscopy (FT-IR), and gel permeation chromatography (GPC). The membrane of SPABES-PAEs was fabricated by the solution casting method, and the membranes were very flexible and transparent with a thickness of 70–90 μm. The morphology of the membranes was observed using atomic force microscope and the ionic domain size was proved by small angle X-ray scattering (SAXS) measurement. The incorporation of polymers including fluorinated units allowed the membranes to provide unprecedented oxidative and dimensional stabilities, as verified from the results of ex situ durability tests and water uptake capacity, respectively. By the collective efforts, we observed an enhanced water retention capacity, reasonable dimensional stability and high proton conductivity, and the peak power density of the SPABES-PAE (2:1) was 333.29 mW·cm−2 at 60 °C under 100% relative humidity (RH). [ABSTRACT FROM AUTHOR]

An important task in health research is to characterize time-to-event outcomes such as disease onset or mortality in terms of a potentially high-dimensional set of risk factors. For example, prospective cohort studies of Alzheimer's disease (AD) typically enroll older adults for observation over several decades to assess the long-term impact of genetic and other factors on cognitive decline and mortality. The accelerated failure time model is particularly well-suited to such studies, structuring covariate effects as "horizontal" changes to the survival quantiles that conceptually reflect shifts in the outcome distribution due to lifelong exposures. However, this modeling task is complicated by the enrollment of adults at differing ages, and intermittent follow-up visits leading to interval-censored outcome information. Moreover, genetic and clinical risk factors are not only high-dimensional, but characterized by underlying grouping structures, such as by function or gene location. Such grouped high-dimensional covariates require shrinkage methods that directly acknowledge this structure to facilitate variable selection and estimation. In this paper, we address these considerations directly by proposing a Bayesian accelerated failure time model with a group-structured lasso penalty, designed for left-truncated and interval-censored time-to-event data. We develop an R package with a Markov chain Monte Carlo sampler for estimation. We present a simulation study examining the performance of this method relative to an ordinary lasso penalty and apply the proposed method to identify groups of predictive genetic and clinical risk factors for AD in the Religious Orders Study and Memory and Aging Project prospective cohort studies of AD and dementia., Competing Interests: Declaration of conflicting interestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: In 2019, the EAT-Lancet Commission proposed a healthy dietary pattern that, along with reductions in food waste and improved agricultural practices, could feed the increasing global population sustainably. We developed a Planetary Health Diet Index (PHDI) to quantify adherence to the EAT-Lancet reference diet., Objectives: We aimed to assess associations between PHDI and total and cause-specific mortality in 3 prospective cohorts of males and females in the United States., Methods: We followed 66,692 females from the Nurses' Health Study (1986-2019), 92,438 females from the Nurses' Health Study II (1989-2019), and 47,274 males from the Health Professionals Follow-up Study (1986-2018) who were free of cancer, diabetes, and major cardiovascular diseases at baseline. The PHDI was calculated every 4 y using a semiquantitative food frequency questionnaire. Hazard ratios (HRs) were calculated using multivariable proportional-hazards models., Results: During follow-up, we documented 31,330 deaths among females and 23,206 among males. When comparing the highest with the lowest quintile of PHDI, the pooled multivariable-adjusted HRs were 0.77 [95% confidence interval (CI): 0.75, 0.80] for all-cause mortality (P-trend < 0.0001). The PHDI was associated with lower risk of deaths from cardiovascular diseases (HR: 0.86; 95% CI: 0.81, 0.91), cancer (HR: 0.90; 95% CI: 0.85, 0.95), respiratory diseases (HR: 0.53; 95% CI: 0.48, 0.59), and neurodegenerative diseases (HR: 0.72; 95% CI: 0.67, 0.78). In females, but not males, the PHDI was also significantly associated with a lower risk of deaths from infectious diseases (HR: 0.62; 95% CI: 0.51, 0.76). PHDI scores were also associated inversely with greenhouse gas emissions and other environmental impacts., Conclusions: In 3 large United States-based prospective cohorts of males and females with up to 34 y of follow-up, a higher PHDI was associated with lower risk of total and cause-specific mortality and environment impacts., (Copyright © 2024 American Society for Nutrition. All rights reserved.)

Experimental studies reported biochemical actions underpinning aging processes and mortality, but the relevant metabolic alterations in humans are not well understood. Here we examine the associations of 243 plasma metabolites with mortality and longevity (attaining age 85 years) in 11,634 US (median follow-up of 22.6 years, with 4288 deaths) and 1878 Spanish participants (median follow-up of 14.5 years, with 525 deaths). We find that, higher levels of N2,N2-dimethylguanosine, pseudouridine, N4-acetylcytidine, 4-acetamidobutanoic acid, N1-acetylspermidine, and lipids with fewer double bonds are associated with increased risk of all-cause mortality and reduced odds of longevity; whereas L-serine and lipids with more double bonds are associated with lower mortality risk and a higher likelihood of longevity. We further develop a multi-metabolite profile score that is associated with higher mortality risk. Our findings suggest that differences in levels of nucleosides, amino acids, and several lipid subclasses can predict mortality. The underlying mechanisms remain to be determined., (© 2023. Springer Nature Limited.)

Objectives: Cone beam CT (CBCT) machines do not always allow for patients to be scanned in the ideal position for image acquisition. This study aimed to investigate the influence of the position/angulation of the mandible relative to the X-ray beam of a CBCT machine., Methods: Five sequential CBCT scans were captured of a human mandible at each angulation of 10°, 20°, 30°, and 40° using a coronal and sagittal positioning. Inspection software utilized a best-fit alignment to automatically calculate the three-dimensional variation at 15 standardized points of interest., Results: Statistically significant differences were found between the dimensional accuracy of CBCT scans taken at 10° (26.3 µm) of coronal angulation, as well as those taken at 20° (-17.3 mm) and 30° (35.2 mm) of sagittal angulations ( p < 0.001, 0.016, and <0.001, respectively). The largest deviations in accuracy included an overall maximum deviation of 490 mm., Conclusions: The position of the mandible with respect to the X-ray beam has a clinically insignificant effect on dimensional accuracy, up to the maximum angle of 40° assessed.

Background: Microbially mediated oral diseases can signal underlying HIV/AIDS progression in HIV-infected adults. The role of the oral microbiota in HIV-infected youth is not known. The Adolescent Master Protocol of the Pediatric HIV/AIDS Cohort Study is a longitudinal study of perinatally HIV-infected (PHIV) and HIV-exposed, uninfected (PHEU) youth. We compared oral microbiome levels and associations with caries or periodontitis in 154 PHIV and 100 PHEU youth., Results: Species richness and alpha diversity differed little between PHIV and PHEU youth. Group differences in average counts met the significance threshold for six taxa; two Corynebacterium species were lower in PHIV and met thresholds for noteworthiness. Several known periodontitis-associated organisms (Prevotella nigrescens, Tannerella forsythia, Aggregatibacter actinomycetemcomitans, and Filifactor alocis) exhibited expected associations with periodontitis in PHEU youth, associations not observed in PHIV youth. In both groups, odds of caries increased with counts of taxa in four genera, Streptococcus, Scardovia, Bifidobacterium, and Lactobacillus., Conclusions: The microbiomes of PHIV and PHEU youth were similar, although PHIV youth seemed to have fewer "health"-associated taxa such as Corynebacterium species. These results are consistent with the hypothesis that HIV infection, or its treatment, may contribute to oral dysbiosis.

Readmission following discharge from an initial hospitalization is a key marker of quality of health care in the United States. For the most part, readmission has been studied among patients with 'acute' health conditions, such as pneumonia and heart failure, with analyses based on a logistic-Normal generalized linear mixed model (Normand et al., 1997). Naïve application of this model to the study of readmission among patients with 'advanced' health conditions such as pancreatic cancer, however, is problematic because it ignores death as a competing risk. A more appropriate analysis is to imbed such a study within the semi-competing risks framework. To our knowledge, however, no comprehensive statistical methods have been developed for cluster-correlated semi-competing risks data. To resolve this gap in the literature we propose a novel hierarchical modeling framework for the analysis of cluster-correlated semi-competing risks data that permits parametric or non-parametric specifications for a range of components giving analysts substantial flexibility as they consider their own analyses. Estimation and inference is performed within the Bayesian paradigm since it facilitates the straightforward characterization of (posterior) uncertainty for all model parameters, including hospital-specific random effects. Model comparison and choice is performed via the deviance information criterion and the log-pseudo marginal likelihood statistic, both of which are based on a partially marginalized likelihood. An efficient computational scheme, based on the Metropolis-Hastings-Green algorithm, is developed and had been implemented in the SemiCompRisks R package. A comprehensive simulation study shows that the proposed framework performs very well in a range of data scenarios, and outperforms competitor analysis strategies. The proposed framework is motivated by and illustrated with an on-going study of the risk of readmission among Medicare beneficiaries diagnosed with pancreatic cancer. Using data on n=5,298 patients at J =112 hospitals in the six New England states between 2000-2009, key scientific questions we consider include the role of patient-level risk factors on the risk of readmission and the extent of variation in risk across hospitals not explained by differences in patient case-mix.

In the U.S., the Centers for Medicare and Medicaid Services uses 30-day readmission, following hospitalization, as a proxy outcome to monitor quality of care. These efforts generally focus on treatable health conditions, such as pneumonia and heart failure. Expanding quality of care systems to monitor conditions for which treatment options are limited or non-existent, such as pancreatic cancer, is challenging because of the non-trivial force of mortality; 30-day mortality for pancreatic cancer is approximately 30%. In the statistical literature, data that arise when the observation of the time to some non-terminal event is subject to some terminal event are referred to as 'semi-competing risks data'. Given such data, scientific interest may lie in at least one of three areas: (i) estimation/inference for regression parameters, (ii) characterization of dependence between the two events, and (iii) prediction given a covariate profile. Existing statistical methods focus almost exclusively on the first of these; methods are sparse or non-existent, however, when interest lies with understanding dependence and performing prediction. In this paper we propose a Bayesian semi-parametric regression framework for analyzing semi-competing risks data that permits the simultaneous investigation of all three of the aforementioned scientific goals. Characterization of the induced posterior and posterior predictive distributions is achieved via an efficient Metropolis-Hastings-Green algorithm, which has been implemented in an R package. The proposed framework is applied to data on 16,051 individuals diagnosed with pancreatic cancer between 2005-2008, obtained from Medicare Part A. We found that increased risk for readmission is associated with a high comorbidity index, a long hospital stay at initial hospitalization, non-white race, male, and discharge to home care.

A new phenolic amide 8, together with the nine known phenolic compounds 1-7, 9 and 10 were isolated from the MeOH extract of the roots of Paris verticillata. The structure of the new compound 8 was determined to be 1-N-feruloylaminobutyl-4-rho-hydroxybenzamide by spectroscopic methods. The isolated compounds were tested for cytotoxicity against four human tumor cell lines using the SRB assay.

Column chromatographic separation of a MeOH extract of the aerial parts of Saussurea triangulata led to the isolation of a new sesquiterpene glycoside 6, together with three quinic acid derivatives, two phenolics, two sesquiterpene glycosides and two flavonoids. The new compound 6 was identified as amarantholidol A glycoside by spectroscopic and chemical methods.

Chromatographic separation of the MeOH extract from the aerial parts of Saussurea pulchella led to the isolation of seven terpenes (1-4, 11-13), and eight phenolics (5-10, 14-15). Their structures were determined by spectroscopic means to be (3S)-3-O-(3',4'-diangeloyl-beta-D-glucopyranosyloxy)-3,7-trimethylocta-1,6-diene (1), 7delta-methoxy- 4(14)- oppositen-1beta-ol (2) 4(15)- eudesmene-1beta, 6alpha-diol (3), 3alpha-hydroxy-5, 6-epoxy-7-megastigmen-9-one (4), (+)-syringaresinol (5), (7S, 8R, 8'R)-5,5'-dimethoxylariciresinol (6), 8alpha-hydroxypinoresinol (7), (7'R, 8'R)-2,2'- dimethoxy-4- (3-hydroxyl-propenyl)-4'-(1,2,3-trihydroxypropyl)-biphenyl ether (8), 4-allyl-2,6- dimethoxyphenyl glucoside (9), 2-methoxy-4-(2-propenyl)phenyl beta-D-glucoside (10), (-)-oplopan-4-one- 10alpha-O-beta-D-glucoside (11), linalyl-O-beta-D-glucoside (12), amarantholidoside IV (13), (+)-1-hydroxypinoresinol 1-O-beta-D-glucoside (14), and syringin (15). Compounds 1-3 and 8-13 were first isolated from the genus Saussurea. The isolated compounds were examined for cytotoxic activity against four human cancer cell lines in vitro using the sulforhodamin B bio assay method.