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1.

Longitudinal studies with binary outcomes characterized by informative right censoring are commonly encountered in clinical, basic, behavioral, and health sciences. Approaches developed to analyze data with binary outcomes were mainly tailored to clustered or longitudinal data with missing completely at random or at random. Studies that focused on informative right censoring with binary outcomes are characterized by their imbedded computational complexity and difficulty of implementation. Here we present a new maximum likelihood-based approach with repeated binary measures modeled in a generalized linear mixed model as a function of time and other covariates. The longitudinal binary outcome and the censoring process determined by the number of times a subject is observed share latent random variables (random intercept and slope) where these subject-specific random effects are common to both models. A simulation study and sensitivity analysis were conducted to test the model under different assumptions and censoring settings. Our results showed accuracy of the estimates generated under this model when censoring was fully informative or partially informative with dependence on the slopes. A successful implementation was undertaken on a cohort of renal transplant patients with blood urea nitrogen as a binary outcome measured over time to indicate normal and abnormal kidney function until the emanation of graft rejection that eventuated in informative right censoring. In addition to its novelty and accuracy, an additional key feature and advantage of the proposed model is its viability of implementation on available analytical tools and widespread application on any other longitudinal dataset with informative censoring.

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2.
Organs‐on‐chip (OoCs) are catching on as a promising and valuable alternative to animal models, in line with the 3Rs initiative. OoCs enable the creation of three‐dimensional (3D) tissue microenvironments with physiological and pathological relevance at unparalleled precision and complexity, offering new opportunities to model human diseases and to test the potential therapeutic effect of drugs, while overcoming the limited predictive accuracy of conventional 2D culture systems. Here, we present a liver‐on‐a‐chip model to investigate the effects of two naturally occurring polyphenols, namely quercetin and hydroxytyrosol, on nonalcoholic fatty liver disease (NAFLD) using a high‐content analysis readout methodology. NAFLD is currently the most common form of chronic liver disease; however, its complex pathogenesis is still far from being elucidated, and no definitive treatment has been established so far. In our experiments, we observed that both polyphenols seem to restrain the progression of the free fatty acid‐induced hepatocellular steatosis, showing a cytoprotective effect due to their antioxidant and lipid‐lowering properties. In conclusion, the findings of the present work could guide novel strategies to contrast the onset and progression of NAFLD.  相似文献   
3.

Backgrounds

An outbreak of lung injury among South Korean adults was examined in a hospital-based case-control study, and the suspected cause was exposure to humidifier disinfectant (HD). However, a case-control study with community-dwelling controls was needed to validate the previous study’s findings, and to confirm the exposure-response relationship between HD and lung injury.

Methods

Each case of lung injury was matched with four community-dwelling controls, according to age (±3 years), sex, residence, and history of childbirth since 2006 (for women). Environmental risk factors, which included type and use of humidifier and HD, were investigated using a structured questionnaire during August 2011. The exposure to HD was calculated for both cases and controls, and the corresponding risks of lung injury were compared.

Results

Among 28 eligible cases, 16 patients agreed to participate, and 60 matched controls were considered eligible for this study. The cases were more likely to have been exposed to HD (odds ratio: 116.1, 95% confidence interval: 6.5–2,063.7). All cases were exposed to HDs containing polyhexamethyleneguanidine phosphate, and the risk of lung injury increased with the cumulative exposure, duration of exposure, and exposure per day.

Conclusions

This study revealed a statistically significant exposure-response relationship between HD and lung injury. Therefore, continuous monitoring and stricter evaluation of environmental chemicals’ safety should be conducted.  相似文献   
4.
Atomically dispersed Fe–N–C catalysts are considered the most promising precious‐metal‐free alternative to state‐of‐the‐art Pt‐based oxygen reduction electrocatalysts for proton‐exchange membrane fuel cells. The exceptional progress in the field of research in the last ≈30 years is currently limited by the moderate active site density that can be obtained. Behind this stands the dilemma of metastability of the desired FeN4 sites at the high temperatures that are believed to be a requirement for their formation. It is herein shown that Zn2+ ions can be utilized in the novel concept of active‐site imprinting based on a pyrolytic template ion reaction throughout the formation of nitrogen‐doped carbons. As obtained atomically dispersed Zn–N–Cs comprising ZnN4 sites as well as metal‐free N4 sites can be utilized for the coordination of Fe2+ and Fe3+ ions to form atomically dispersed Fe–N–C with Fe loadings as high as 3.12 wt%. The Fe–N–Cs are active electocatalysts for the oxygen reduction reaction in acidic media with an onset potential of E0 = 0.85 V versus RHE in 0.1 m HClO4. Identical location atomic resolution transmission electron microscopy imaging, as well as in situ electrochemical flow cell coupled to inductively coupled plasma mass spectrometry measurements, is employed to directly prove the concept of the active‐site imprinting approach.  相似文献   
5.
This study examined the partitioning of organic matter intoparticulate organic carbon (POC) and dissolved organic carbon(DOC) pools in nutrient-enriched enclosures containing naturalplankton from the Gulf of Trieste (northern Adriatic), an areaaffected by mucilage. The strategy of nutrient additions wasto introduce a pulse of new nutrients in concentrations thatmimic natural inputs and to survey community structure and organicmatter fluxes long enough so that plankton became nutrient-limited.Maximal bacterial biomass attained roughly double the initialvalue, while autotrophic carbon increased by nearly an orderof magnitude. The microflagellate-dominated community releasedmore DOC per unit biomass (5.5 ± 7.2 to 50.6 ±28.0 µg C µg Chl a-1 day-1 versus 3.4 ± 3.4to 10.8 ± 4.6 µg C µg Chl a-1 day-1 for diatom-dominatedphytoplankton), POC increase was modest (~300 µg C l-1)and there was little change in DOC. Organic carbon partitioningduring two experiments in which diatoms prevailed was dominatedby POC (>800 µg C l-1) in the exponential growth phasewith an increasing contribution of particulate carbohydratesthat paralleled gradual nutrient depletion. Transition to thestationary phase and the decay of autotrophic communities wereaccompanied by the net accumulation of a carbohydrate-rich DOC.  相似文献   
6.
7.
In the 1975-2004 period, 130 cases of pterygium were estimated, 83 males and 47 females, on a small island Rab. Island Rab is located in the north part of the Adriatic sea, which has very high index of sun radiation. Pterygium is usually histopathologically defined as a hyperplasia of conjunctival tissue, elastoid degeneration of subepithelieum and fragmentation of Bowman's membrane. Our histopathological findings in 73 eyes are following: conjunctiva with neovascularisation, leukocyte margination and subepithelial basophilic degeneration, proliferation of conjunctival tissue, acanthosis and squamous metaplasia, and mucinous elements, focaly present plasma cells, focuses of increased pigmentisation in basal epithelial layers, tenon capsule with edema, diffuse neovascularisation and fragmentation of fibrils. These findings suggest that in severe cases of pterygium histopathologically exists precancerosis. In conclusion, on the basis of these histopathological findings, especially in the Tenon capsule, we suggest that for surgical procedure of pterygium the excision of the Tenon capsule, extensively under pterygium, is necessary.  相似文献   
8.
The aim of this epidemiologic study, on small island Rab, in North Adriatic Sea, is to estimate correlation between climatic factors, specially chronic exposure to strong visible and UV light, and appearance of pterygium and exfoliation syndrome. In the first group of population which live in a village and who are agriculturists and fishermen (480 persons) appearance of pterygium is in 23% (16% in males and 7% in females), but 0.0% in urban people (61 people). The appearance of exfoliation syndrome was in the first group of agriculturists and fishermen population in 21%, of which 19% of males and 2% of females, and in urban people 0.0%. The higher intraocular pressure in exfoliation syndrome was 92%. All population in this examination were in the highest age (mean age is 65-80 years). Chronic exposure to sunlight caused the high percentage appearance of pterygium and exfoliation syndrome.  相似文献   
9.
Autoerotic fatalities refer to a death resulting from the participation in a sex-related activity designed to heighten sexual arousal. The overwhelming majority of these deaths are due to asphyxia, most often by hanging or ligature compression of the neck. Here we report a case of "atypical" autoerotic fatality in which death was not induced by ligature compression. Unusual death of a 24-year-old man, involving propane inhalation and plastic bag suffocation, is described. The special characteristics of propane gas as an asphyxiant agent are discussed, as well as its effect on the human body.  相似文献   
10.
Deforestation is rapidly transforming primary forests across the tropics into human-dominated landscapes. Consequently, conservationists need to understand how different taxa respond and adapt to these changes in order to develop appropriate management strategies. Our two year study seeks to determine how wild Sumatran orangutans (Pongo abelii) adapt to living in an isolated agroforest landscape by investigating the sex of crop-raiders related to population demographics, and their temporal variations in feeding behaviour and dietary composition. From focal animal sampling we found that nine identified females raided cultivated fruits more than the four males. Seasonal adaptations were shown through orangutan feeding habits that shifted from being predominantly fruit-based (56% of the total feeding time, then 22% on bark) to the fallback food of bark (44%, then 35% on fruits), when key cultivated resources such as jackfruit (Artocarpus integer), were unavailable. Cultivated fruits were mostly consumed in the afternoon and evening, when farmers had returned home. The finding that females take greater crop-raiding risks than males differs from previous human-primate conflict studies, probably because of the low risks associated (as farmers rarely retaliated) and low intraspecific competition between males. Thus, the behavioral ecology of orangutans living in this human-dominated landscape differs markedly from that in primary forest, where orangutans have a strictly wild food diet, even where primary rainforests directly borders farmland. The importance of wild food availability was clearly illustrated in this study with 21% of the total orangutan feeding time being allocated to feeding on cultivated fruits. As forests are increasingly converted to cultivation, humans and orangutans are predicted to come into conflict more frequently. This study reveals orangutan adaptations for coexisting with humans, e.g. changes in temporal foraging patterns, which should be used for guiding the development of specific human-wildlife conflict mitigation strategies to lessen future crop-raiding and conflicts.  相似文献   
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