Upside-Down Adsorption: The Counterintuitive Influences of Surface Entropy and Surface Hydroxyl Density on Hydrogen Spillover.

Although hydrogen spillover is often invoked to explain anomalies in catalysis, spillover remains a poorly understood phenomenon. Hydrogen spillover (H*) is best described as highly mobile H atom equivalents that arise when H2 migrates from a metal nanoparticle to an oxide or carbon support. In the 60 years since its discovery, few methods have become available to quantify or characterize H*-support interactions. We recently showed in situ infrared spectroscopy and volumetric chemisorption can quantify reversible H2 adsorption on Au/TiO2 catalysts, where adsorbed hydrogen exists as H* and interacts with titania surface hydroxyl (TiOH) groups. Here, we report parallel thermogravimetric analysis and Fourier transform infrared spectroscopy methods for systematically manipulating the surface TiOH density. We examine the role of surface hydroxylation on spillover thermodynamics using van't Hoff studies to determine apparent adsorption enthalpies and entropies at constant H* coverage, which is necessary to maintain constant H* translational entropy. Although surface TiOH groups are the likely adsorption sites, the data show removing hydroxyl groups increases spillover. This surprising finding─that adsorption increases as the adsorption site density decreases─is associated with improved thermodynamics on dehydroxylated surfaces. A strong adsorption enthalpy-entropy correlation implicates the changing surface entropy of the titania support itself (i.e., an initial state effect) is deeply intertwined with the H* configurational entropy. These effects are surprising and should apply to all low-coverage adsorbates where entropy terms dominate more traditional enthalpic considerations. Moreover, this study points toward a kinetic test for invoking spillover in a reaction mechanism: namely, in situ dehydroxylation should enhance spillover processes.

Identifying obesity subtypes: A review of studies utilising clinical biomarkers and genetic data.

Obesity is a complex and multifactorial condition that poses significant health risks. Recent advancements in our understanding of obesity have highlighted the heterogeneity within this disorder. Identifying distinct subtypes of obesity is crucial for personalised treatment and intervention strategies. This review paper aims to examine studies that have utilised clinical biomarkers and genetic data to identify clusters or subtypes of obesity. The findings of these studies may provide valuable insights into the underlying mechanisms and potential targeted approaches for managing obesity-related health issues such as type 2 diabetes.

Evaluation of Pediatric Hematology Referrals at a Tertiary University Hospital in West Texas.

One in 40 pediatric office visits in the United States result in referral to subspecialty care, mostly for secondary opinion. The aim of this study was to evaluate the necessity of pediatric hematology referrals from Eastern New Mexico and West Texas to a tertiary university hospital. Retrospective data was obtained from chart review based on referrals made to the Southwest Cancer Center in Lubbock, TX for abnormal complete blood count or coagulation tests. Necessity of referrals were assessed according to patient laboratory values before referral, at initial visit, and whether therapy was started by the primary care physician (PCP). One hundred one patients met the study criteria during the period in review. The most common reasons of referral were iron deficiency anemia, leukopenia or leukocytosis and other types of anemia. About 33% of the referrals were determined to be manageable by a PCP as either the correct therapy had been already started before referral and/or the laboratory values were back to normal at the time of the first subspecialty visit. The total estimated cost of unnecessary referrals, including clinic visits and laboratories were $82,888 excluding mileage costs, days of work-school missed, and child care. Incorporation of referral guidelines, improving communication between PCP and subspecialties, and utilizing age-sex appropriate values in the interpretation of results could prevent excessive subspecialty referrals.

Genetic Evidence for Distinct Biological Mechanisms That Link Adiposity to Type 2 Diabetes: Toward Precision Medicine.

We aimed to unravel the mechanisms connecting adiposity to type 2 diabetes. We used MR-Clust to cluster independent genetic variants associated with body fat percentage (388 variants) and BMI (540 variants) based on their impact on type 2 diabetes. We identified five clusters of adiposity-increasing alleles associated with higher type 2 diabetes risk (unfavorable adiposity) and three clusters associated with lower risk (favorable adiposity). We then characterized each cluster based on various biomarkers, metabolites, and MRI-based measures of fat distribution and muscle quality. Analyzing the metabolic signatures of these clusters revealed two primary mechanisms connecting higher adiposity to reduced type 2 diabetes risk. The first involves higher adiposity in subcutaneous tissues (abdomen and thigh), lower liver fat, improved insulin sensitivity, and decreased risk of cardiometabolic diseases and diabetes complications. The second mechanism is characterized by increased body size and enhanced muscle quality, with no impact on cardiometabolic outcomes. Furthermore, our findings unveil diverse mechanisms linking higher adiposity to higher disease risk, such as cholesterol pathways or inflammation. These results reinforce the existence of adiposity-related mechanisms that may act as protective factors against type 2 diabetes and its complications, especially when accompanied by reduced ectopic liver fat.

Modified frailty index and hypoalbuminemia as predictors of adverse outcomes in older adults presenting to acute general surgical unit.

INTRODUCTION: Health professionals are progressively drawing on the concept of frailty as a determinant of adverse surgical outcomes in of older adults. We aimed to determine the prevalence of frailty and the correlation between frailty and mortality among older adults admitted to the acute surgical unit. MATERIALS AND METHODS: This prospective cohort study was conducted in the acute general surgical unit over a two month period. We recruited 150 consecutive patients aged 65yrs and above. The modified frailty index was employed to measure frailty and the albumin levels on admission were obtained from electronic medical records. The patients were followed up for a period of thirty days. RESULTS: We found that more than 40% of the older adults admitted to the acute general surgical unit were frail and frailty was associated with higher rate of mortality at 30 days. Hypoalbuminemia was associated with a longer length of stay, higher rate of complications, and an increased likelihood of discharge to a rehabilitation facility. There was also a significant univariate correlation between frailty and the presence of hypoalbuminemia on admission. CONCLUSION: Frailty and hypoalbuminemia are common in older general surgical patients and predict the likelihood of some of the adverse outcomes relevant to older adults and health economy such as mortality, increased length of stay, rate of complications, and likelihood of discharge to a rehabilitation facility. Further studies should investigate a possible causal association between frailty and low albumin levels in an acute surgical setting.