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Letter from the Editor
Get PDFWelcome to our inaugural issue from Editor-in-Chief Angela Clark-Taylor, Ph.D
A Haptoglobin (HP) Structural Variant Alters the Effect of APOE Alleles on Alzheimer\u27s Disease
Get PDFBackground: Haptoglobin (HP) is an antioxidant of apolipoprotein E (APOE), and previous reports have shown HP binds with APOE and amyloid beta (Aβ) to aid its clearance. A common structural variant of the HP gene distinguishes it into two alleles: HP1 and HP2. Methods: HP genotypes were imputed in 29 cohorts from the Alzheimer\u27s Disease Genetics Consortium (N = 20,512). Associations between the HP polymorphism and Alzheimer\u27s disease (AD) risk and age of onset through APOE interactions were investigated using regression models. Results: The HP polymorphism significantly impacts AD risk in European-descent individuals (and in meta-analysis with African-descent individuals) by modifying both the protective effect of APOE ε2 and the detrimental effect of APOE ε4. The effect is particularly significant among APOE ε4 carriers. Discussion: The effect modification of APOE by HP suggests adjustment and/or stratification by HP genotype is warranted when APOE risk is considered. Our findings also provided directions for further investigations on potential mechanisms behind this association
Effects of Honey Locust Seed Pods on the Behavior and Nutrient Intake of Zoo-Housed François Langurs and Prehensile-Tailed Porcupines
No full textSeed pods represent an under-utilized and valuable dietary resource for zoos because they encourage naturalistic extractive foraging behavior and because seeds pods, like leafy browses, are more fiber-rich than most dietary items typically offered in zoos. The primary goal of this study was to examine the effects of honey locust (Gleditsia triacanthos) seed pods on the behavior and macronutrient intake of zoo-housed François’ langurs (Trachypithecus francoisi; n = 3) and prehensile-tailed porcupines (Coendou prehensilis; n = 2) using a pre- versus postdiet implementation design. From December 2019 to April 2020, we recorded behavior using instantaneous interval sampling and daily macronutrient intake via dietary intake records. We found that time spent feeding increased (p \u3c.001) and stereotypic behaviors decreased (p \u3c.001) for the François’ langur group during the seed pod phase. The prehensile-tailed porcupines also exhibited increased time spent feeding and decreased inactivity (p \u3c.001 for all comparisons) during the experimental seed pod phase. We found no differences in macronutrient intake for the François’ langur group. The female prehensile-tailed porcupine consumed more neutral detergent fiber (NDF) in the seed pod phase (p =.003) and the male consumed more crude protein, NDF, nonstructural carbohydrates, and crude fat (p \u3c.001 for all comparisons). We stress that honey locust seed pods are a fiber-rich (i.e., ~40%–55% NDF by dry weight) dietary option for zoo-housed folivores and promote positive welfare by encouraging naturalistic foraging behavior and may help increase foraging time and decrease stereotypic behaviors
Self-Calibrated Subspace Reconstruction for Multidimensional Mr Fingerprinting for Simultaneous Relaxation and Diffusion Quantification
No full textPurpose: To propose a new reconstruction method for multidimensional MR fingerprinting (mdMRF) to address shading artifacts caused by physiological motion-induced measurement errors without navigating or gating. Methods: The proposed method comprises two procedures: self-calibration and subspace reconstruction. The first procedure (self-calibration) applies temporally local matrix completion to reconstruct low-resolution images from a subset of under-sampled data extracted from the k-space center. The second procedure (subspace reconstruction) utilizes temporally global subspace reconstruction with pre-estimated temporal subspace from low-resolution images to reconstruct aliasing-free, high-resolution, and time-resolved images. After reconstruction, a customized outlier detection algorithm was employed to automatically detect and remove images corrupted by measurement errors. Feasibility, robustness, and scan efficiency were evaluated through in vivo human brain imaging experiments. Results: The proposed method successfully reconstructed aliasing-free, high-resolution, and time-resolved images, where the measurement errors were accurately represented. The corrupted images were automatically and robustly detected and removed. Artifact-free T1, T2, and ADC maps were generated simultaneously. The proposed reconstruction method demonstrated robustness across different scanners, parameter settings, and subjects. A high scan efficiency of less than 20 s per slice has been achieved. Conclusion: The proposed reconstruction method can effectively alleviate shading artifacts caused by physiological motion-induced measurement errors. It enables simultaneous and artifact-free quantification of T1, T2, and ADC using mdMRF scans without prospective gating, with robustness and high scan efficiency
Cold Gas Disks in Main-Sequence Galaxies at Cosmic Noon: Low Turbulence, Flat Rotation Curves, and Disk-Halo Degeneracy
Get PDFWe study the dynamics of cold molecular gas in two main-sequence galaxies at cosmic noon (zC-488879 at z ≃ 1.47 and zC-400569 at z ≃ 2.24) using new high-resolution ALMA observations of multiple 12CO transitions. For zC-400569 we also reanalyze high-quality Hα data from the SINS/zC-SINF survey. We find that (1) both galaxies have regularly rotating CO disks and their rotation curves are flat out to ∼8 kpc contrary to previous results pointing to outer declines in the rotation speed Vrot; (2) the intrinsic velocity dispersions are low (σCO ≲ 15 km s-1 for CO and σHα ≲ 37 km s-1 for Hα) and imply Vrot/σCO ≳ 17-22 yielding no significant pressure support; (3) mass models using HST images display a severe disk-halo degeneracy, that is models with inner baryon dominance and models with cuspy dark matter halos can fit the rotation curves equally well due to the uncertainties on stellar and gas masses; and (4) Milgromian dynamics (MOND) can successfully fit the rotation curves with the same acceleration scale a0 measured at z ≃ 0. The question of the amount and distribution of dark matter in high-z galaxies remains unsettled due to the limited spatial extent of the available kinematic data; we discuss the suitability of various emission lines to trace extended rotation curves at high z. Nevertheless, the properties of these two high-z galaxies (high Vrot/σV ratios, inner rotation curve shapes, bulge-to-total mass ratios) are remarkably similar to those of massive spirals at z ≃ 0, suggesting weak dynamical evolution over more than 10 Gyr of the Universe\u27s lifetime
Prevalence and Factors Associated With Pre-Hospital Delay Among Acute Stroke Patients at Mulago and Kiruddu National Referral Hospitals, Kampala: a Cross-Sectional Study
No full textBackground: Despite advancements in acute stroke care, acute stroke patients present late for care resulting in high mortality and poor functional outcomes. This study determined the prevalence of pre-hospital delay and associated factors among adult acute stroke patients in Uganda. Methods: In a hospital based, cross-sectional study, one hundred and forty-three study participants with confirmed acute stroke presenting to the emergency units of Mulago and Kiruddu national referral hospitals were enrolled. Using an interviewer-administered questionnaire, details on sociodemographics, onset of stroke, arrival at the tertiary facility, health system and clinical factors were collected. Descriptive statistics and modified Poisson regression analyses were performed to determine factors associated with prehospital delay. Results: Among the 143 study participants, nearly two-thirds (79/146) had ischemic stroke while a third (59/143) had haemorrhagic stroke. The mean age was 59 years (SD 16) and 51.7% of acute stroke patients were males. Ninety one percent (130/143) presented to the emergency unit after 3 hours. The majority (124/143) reported visiting lower-level facilities prior to referral to the tertiary facility. Staying outside Kampala district (PR: 1.28 (1.22–1.34), p \u3c 0.001), and using hired or government ambulance for transport to tertiary facility (PR: 1.17 (1.13–1.20), p \u3c 0.001) were associated with pre-hospital delay. Conclusions: Prevalence of pre-hospital delay among acute stroke patients presenting to public tertiary hospitals in Uganda is very high. The causes of pre hospital delay should be further explored qualitatively. Efforts to reduce prehospital delay should include improving pre-hospital transport systems for stroke patients
Modular Design of a Polymer-Bilayer-Based Mechanically Compliant Worm-Like Robot
No full textSoft earthworm-like robots that exhibit mechanical compliance can, in principle, navigate through uneven terrains and constricted spaces that are inaccessible to traditional legged and wheeled robots. However, unlike the biological originals that they mimic, most of the worm-like robots reported to date contain rigid components that limit their compliance, such as electromotors or pressure-driven actuation systems. Here, a mechanically compliant worm-like robot with a fully modular body that is based on soft polymers is reported. The robot is composed of strategically assembled, electrothermally activated polymer bilayer actuators, which are based on a semicrystalline polyurethane with an exceptionally large nonlinear thermal expansion coefficient. The segments are designed on the basis of a modified Timoshenko model, and finite element analysis simulation is used to describe their performance. Upon electrical activation of the segments with basic waveform patterns, the robot can move through repeatable peristaltic locomotion on exceptionally slippery or sticky surfaces and it can be oriented in any direction. The soft body enables the robot to wriggle through openings and tunnels that are much smaller than its cross-section
Incidence of Aggressive End-of-Life Care among Older Adults with Metastatic Cancer Living in Nursing Homes and Community Settings
No full textImportance: Nearly 10% of the 1.5 million persons residing in nursing homes (NHs) have received or will receive a diagnosis of cancer. Although aggressive end-of-life (EOL) care is common among community-dwelling patients with cancer, little is known about such patterns of care among NH residents with cancer. Objective: To compare markers of aggressive EOL care between older adults with metastatic cancer who are NH residents and their community-dwelling counterparts. Design, Setting, and Participants: This cohort study used the Surveillance, Epidemiology, and End Results database linked with the Medicare database and the Minimum Data Set (including NH clinical assessment data) for deaths occurring from January 1, 2013, to December 31, 2017, among 146329 older patients with metastatic breast, colorectal, lung, pancreas, or prostate cancer, with a lookback period in claims data through July 1, 2012. Statistical analysis was conducted between March 2021 and September 2022. Exposures: Nursing home status. Main Outcomes and Measures: Markers of aggressive EOL care were cancer-directed treatment, intensive care unit admission, more than 1 emergency department visit or more than 1 hospitalization in the last 30 days of life, hospice enrollment in the last 3 days of life, and in-hospital death. Results: The study population included 146329 patients 66 years of age or older (mean [SD] age, 78.2 [7.3] years; 51.9% men). Aggressive EOL care was more common among NH residents than community-dwelling residents (63.6% vs 58.3%). Nursing home status was associated with 4% higher odds of receiving aggressive EOL care (adjusted odds ratio [aOR], 1.04 [95% CI, 1.02-1.07]), 6% higher odds of more than 1 hospital admission in the last 30 days of life (aOR, 1.06 [95% CI, 1.02-1.10]), and 61% higher odds of dying in the hospital (aOR, 1.61 [95% CI, 1.57-1.65]). Conversely, NH status was associated with lower odds of receiving cancer-directed treatment (aOR, 0.57 [95% CI, 0.55-0.58]), intensive care unit admission (aOR, 0.82 [95% CI, 0.79-0.84]), or enrollment in hospice in the last 3 days of life (aOR, 0.89 [95% CI, 0.86-0.92]). Conclusions and Relevance: Despite increased emphasis to reduce aggressive EOL care in the past several decades, such care remains common among older persons with metastatic cancer and is slightly more prevalent among NH residents than their community-dwelling counterparts. Multilevel interventions to decrease aggressive EOL care should target the main factors associated with its prevalence, including hospital admissions in the last 30 days of life and in-hospital death.
Effects of UV Radiation on Natural and Synthetic Materials
Get PDFThe deleterious effects of solar ultraviolet (UV) radiation on construction materials, especially wood and plastics, and the consequent impacts on their useful lifetimes, are well documented in scientific literature. Any future increase in solar UV radiation and ambient temperature due to climate change will therefore shorten service lifetimes of materials, which will require higher levels of stabilisation or other interventions to maintain their lifetimes at the present levels. The implementation of the Montreal Protocol and its amendments on substances that deplete the ozone layer, controls the solar UV-B radiation received on Earth. This current quadrennial assessment provides a comprehensive update on the deleterious effects of solar UV radiation on the durability of natural and synthetic materials, as well as recent innovations in better stabilising of materials against solar UV radiation-induced damage. Pertinent emerging technologies for wood and plastics used in construction, composite materials used in construction, textile fibres, comfort fabric, and photovoltaic materials, are addressed in detail. Also addressed are the trends in technology designed to increase sustainability via replacing toxic, unsustainable, legacy additives with ‘greener’ benign substitutes that may indirectly affect the UV stability of the redesigned materials. An emerging class of efficient photostabilisers are the nanoscale particles that include oxide fillers and nanocarbons used in high-performance composites, which provide good UV stability to materials. They also allow the design of UV-shielding fabric materials with impressive UV protection factors. An emerging environmental issue related to the photodegradation of plastics is the generation of ubiquitous micro-scale particles from plastic litter exposed to solar UV radiation. Graphical abstract: [Figure not available: see fulltext.
Impacts of Variable Viscosity and Chemical Reaction on Ohmic Dissipative Fluid Flow in a Porous Medium over a Stretching Sheet with Thermal Radiation
No full textThis study investigates the chemical reaction influence on heat transfer flow of viscous Newtonian fluid over a moving surface under the intensity of nonuniform heat source/sink. Variable fluid viscosity and ohmic heating effects are considered in the model equation. The uniqueness of the present investigation is to scrutinize the significance of nonuniform heat source/sink and ohmic heating on the heat transfer flow of optically thin radiative fluid in a permeable medium. The flow equations of continuity, momentum, thermal and solutal fields are converted by invoking relevant dimensionless variables. Also, the converted nonlinear equations are analyzed numerically by using the fourth order Runge–Kutta Fehlberg approach. The significance of model parameters are scrutinized and discussed in detail via graphs and tables. The important findings of this study are the effects of Joule heating (Figure presented.), viscous dissipation parameter (Figure presented.), variable fluid property parameter (Figure presented.) and radiation parameter (Figure presented.) on fluid flow, energy profile and solutal field. The results show that the thermal field depreciates as the Prandtl number increases but escalates against higher values of Joule heating parameter and Brinkman number. Also, the outcome of this study reveals that an enhancement in the values of variable viscosity parameter declines velocity distribution. Concentration distributions behave as a growing function of the Soret number and diminishing function of the Schmidt number. Furthermore, contrasting this study with existing results reveals excellent agreement
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