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The passive capture of clean water from humid air without reliance on bulky equipment and high energy has been a substantial challenge and has attracted significant interest as a potential environmentally friendly alternative to traditional water harvesting methods. Metal-organic frameworks (MOFs) offer a high potential for this application due to their structural versatility which permits scalable, facile modulations of structural and functional elements. Although MOFs are promising materials for water harvesting, little research has been done to address the microstructure-adsorbing characteristics relationship with respect to the dynamic adsorption-desorption process. In this article, we present a parametric study of nine hydrolytically stable MOFs with diverse structures for unraveling fundamental material properties that govern the kinetics of water sequestration in this class of materials as well as investigating overall uptake capacity gravimetrically. The effects of temperature, relative humidity, and powder bed thickness on the adsorption-desorption process are explored for achieving optimal operational parameters. We found that Zr-MOF-808 can produce up to 8.66 L H2O kg −1 MOF day −1 , an extraordinary finding that outperforms any previously reported values for MOF-based systems. The presented findings help to deepen our understanding and guide the discovery of next-generation water harvesting materials.

History of incarceration is associated with an excess of morbidity and mortality. While the incarceration experience itself comes with substantive health risks (e.g., injury, psychological stress, exposure to infectious disease), most individuals eventually return from prison to the general population where they will be diagnosed with the same age-related conditions that drive mortality in the non-incarcerated population but at exaggerated rates. However, the interplay between history of incarceration as a risk factor and more traditional risk factors for age-related diseases (e.g., genetic risk factors) has not been studied. Here, we focus on cognitive impairment, a hallmark of neurodegenerative conditions like Alzheimer’s disease, as an age-related state that may be uniquely impacted by the confluence of environmental stressors (e.g., incarceration) and genetic risk factors. Using data from the Health and Retirement Study, we found that incarceration and APOE-ε4 genotype (i.e., the chief genetic risk factor for Alzheimer’s disease) both constituted substantive risk factors for cognitive impairment in terms of overall risk and earlier onset. The observed effects were mutually independent, however, suggesting that the risk conveyed by incarceration and APOE-ε4 genotype operate across different risk pathways. Our results have implications for the study of criminal-legal contact as a public health risk factor for age-related, neurodegenerative conditions.

The steroidal neurotoxin (-)-batrachotoxin functions as a potent agonist of voltagegated sodium ion channels (Navs). Here we report concise asymmetric syntheses of the natural (-) and non-natural (+) antipodes of batrachotoxin, as well both enantiomers of a C-20 benzoate-modified derivative. Electrophysiological characterization of these molecules against Nav subtypes establishes the non-natural toxin enantiomer as a reversible antagonist of channel function, markedly different in activity from (-)-batrachotoxin. Protein mutagenesis experiments implicate a shared binding side for the enantiomers in the inner pore cavity of Nav. These findings motivate and enable subsequent studies aimed at revealing how small molecules that target the channel inner pore modulate Nav dynamics.

Aggregation of data collected in 28 controlled experiments reveals reproducible debris‐flow behavior that provides a clear target for model tests. In each experiment ∼10 m3 of unsorted, water‐saturated sediment composed mostly of sand and gravel discharged from behind a gate, descended a steep, 95‐m flume, and formed a deposit on a nearly horizontal runout surface. Experiment subsets were distinguished by differing basal boundary conditions (1 versus 16 mm roughness heights) and sediment mud contents (1 versus 7 percent dry weight). Sensor measurements of evolving flow thicknesses, basal normal stresses, and basal pore fluid pressures demonstrate that debris flows in all subsets developed dilated, coarse‐grained, high‐friction snouts, followed by bodies of nearly liquefied, finer‐grained debris. Mud enhanced flow mobility by maintaining high pore pressures in flow bodies, and bed roughness reduced flow speeds but not distances of flow runout. Roughness had these effects because it promoted debris agitation and grain‐size segregation, and thereby aided growth of lateral levees that channelized flow. Grain‐size segregation also contributed to development of ubiquitous roll waves, which had diverse amplitudes exhibiting fractal number‐size distributions. Despite the influence of these waves and other sources of dispersion, the aggregated data have well‐defined patterns that help constrain individual terms in a depth‐averaged debris‐flow model. The patterns imply that local flow resistance evolved together with global flow dynamics, contradicting the hypothesis that any consistent rheology applied. We infer that new evolution equations, not new rheologies, are needed to explain how characteristic debris‐flow behavior emerges from the interactions of debris constituents.

The poison dart toxin batrachotoxin is exceptional for its high potency and toxicity, and for its multifaceted modification of the function of voltage-gated sodium channels. By using cryogenic electron microscopy, we identify two homologous, but nonidentical receptor sites that simultaneously bind two molecules of toxin, one at the interface between Domains I and IV, and the other at the interface between Domains III and IV of the cardiac sodium channel. Together, these two bound toxin molecules stabilize α/π helical conformation in the S6 segments that gate the pore, and one of the bound BTX-B molecules interacts with the crucial Lys1421 residue that is essential for sodium conductance and selectivity via an apparent water-bridged hydrogen bond. Overall, our structure provides insight into batrachotoxin’s potency, efficacy, and multifaceted functional effects on voltage-gated sodium channels via a dual receptor site mechanism. The poison dart toxin batrachotoxin is the most lethal voltage-gated sodium channel toxin. Here authors identify the toxin bound specifically at two homologous receptor sites, which cause channel hyperactivation by positively modulating channel gating and altering ion conductance.

Streptococcus mutans is the primary oral caries-forming bacteria, adept at producing “sticky” biofilms via the synthesis of insoluble extracellular polysaccharides (EPS), catalyzed by glucosyltransferases (GTFs). To circumvent the use of broad-spectrum antibiotics to combat these bacteria, this study sought to modify existing EPS-targeting small molecules with the ultimate goal of producing anti-biofilm polymer surfaces specifically targeting S. mutans . To achieve this, a known GTF inhibitor (G43) was modified with methoxy or tetraethyleneglycol substitutions in different positions (nine derivatives, tested at 50-µM) to pinpoint potential sites for future methacrylate functionalization, and then assessed against single-species S. mutans biofilms. As expected, the compounds did not diminish the bacterial viability. In general, the compounds with methoxy substitution were not effective in reducing EPS formation, whereas the tetraethyleneglycol substitution (G43-C3-TEG) led to a decrease in the concentration of insoluble EPS, although the effect is less pronounced than for the parent G43. This aligns with the reduced GTF-C activity observed at different concentrations of G43-C3-TEG, as well as the consequent decrease in EPS formation, and notable structural changes. In summary, this study determined that G43-C3-TEG is non-bactericidal and can selectively reduce the biofilm formation, by decreasing the production of EPS. This molecule will serve to functionalize surfaces of materials to be tested in future research.

Debris flows typically occur when intense rainfall or snowmelt triggers landslides or extensive erosion on steep, debris-mantled slopes. The flows can then grow dramatically in size and speed as they entrain material from their beds and banks, but the mechanism of this growth is unclear. Indeed, momentum conservation implies that entrainment of static material should retard the motion of the flows if friction remains unchanged. Here we use data from large-scale experiments to assess the entrainment of bed material by debris flows. We find that entrainment is accompanied by increased flow momentum and speed only if large positive pore pressures develop in wet bed sediments as the sediments are overridden by debris flows. The increased pore pressure facilitates progressive scour of the bed, reduces basal friction and instigates positive feedback that causes flow speed, mass and momentum to increase. If dryer bed sediment is entrained, however, the feedback becomes negative and flow momentum declines. We infer that analogous feedbacks could operate in other types of gravity-driven mass flow that interact with erodible beds. The mechanisms by which debris flows acquire mass and momentum as they entrain material are unclear. Large-scale experiments suggest that the pore pressure of wet bed sediment increases as the flow moves over the bed, leading to reduced friction and progressive scouring of the base.

The prevalence of, and link between, mental health disorders—such as traumatic brain injury (TBI) and post-traumatic stress disorder (PTSD)—and antisocial behavior is well-documented among the military veteran population. Studies also show that TBI and PTSD account for variation in prison-based and re-entry outcomes. Despite this body of research, comparatively fewer studies have explicitly focused on how these factors affect prison adjustment for inmates with prior military experience. We used administrative data provided by the Minnesota Department of Corrections (MnDOC) and employed a series of survival analyses to examine how prior diagnoses of TBI and PTSD (among other risk factors) influence metrics of institutional adjustment and recidivism among a sample of military veterans. Our results indicate that the effects of TBI, PTSD, and other indicators of criminogenic risk are relevant when examining the experiences of justice-involved military veterans—especially with respect recidivism-based outcomes. The implications of our results are discussed and directions for future research are given.

Military veteran status has been associated with a variety of criminal justice outcomes as well as higher rates of mental illness and suicide when compared to the general population. Although research has generally focused on why veterans become involved with the justice system, less is known about their experiences while incarcerated. In particular, studies of veterans in the community context indicate that they are unwilling to seek out mental health treatment due to potential stigmas, suggesting that this reluctance may extend into the prison environment. Using a sample of 14,278 veteran and nonveteran inmates, we find that veterans do not necessarily fare worse in prison and are actually more likely to obtain treatment. However, this effect is largely mediated by the greater history of mental disorders and suicidal behaviors among veterans. Our findings lend credence to recent efforts designed to screen and manage justice-involved veterans as a distinct, at-risk group.

Pancreatitis encompasses pancreatic tissue inflammation due to enzymatic autodigestion, leading to complications such as pancreatic pseudocysts. This report details a case in which the administration of glucagon-like peptide-1 (GLP-1) agonists rendered a regressing, asymptomatic pseudocyst symptomatic. We posit that, absent other triggers, GLP-1 agonists might exacerbate pseudocysts. This emphasizes timely diagnosis and proper management. Our investigation delves into patient-specific nuances, potential mechanistic insights, the need to study this phenomenon among a broader cohort, alternative pathologies, long-term consequences, and clinical ramifications in response to a shifting pseudocyst behavior.Pancreatitis encompasses pancreatic tissue inflammation due to enzymatic autodigestion, leading to complications such as pancreatic pseudocysts. This report details a case in which the administration of glucagon-like peptide-1 (GLP-1) agonists rendered a regressing, asymptomatic pseudocyst symptomatic. We posit that, absent other triggers, GLP-1 agonists might exacerbate pseudocysts. This emphasizes timely diagnosis and proper management. Our investigation delves into patient-specific nuances, potential mechanistic insights, the need to study this phenomenon among a broader cohort, alternative pathologies, long-term consequences, and clinical ramifications in response to a shifting pseudocyst behavior.