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According to the United States Eye Injury Registry, eye injury is the leading cause of monocular blindness, and there are approximately 2.4 million eye injuries occurring annually in the US, resulting in 500,000 years of lost eyesight annually.1 These injuries occur more often in males (>70%), and 95% of occupational injuries occur in males.2,3 This chapter will describe the approach to the patient with eye trauma in the emergency department (ED), including how to perform a detailed history and physical examination related to eye injuries, as well as covering the traumatic presentations in Table 9.1.
We previously demonstrated that electrode architectures comprising nanoscale birnessite-like MnOx affixed to three-dimensional carbon nanofoam (CNF) scaffolds offer performance advantages when used as cathodes in rechargeable zinc-ion cells. To discern chemical and physical changes at the MnOx@CNF electrode upon deep charge/discharge in aqueous Zn2+-containing electrolytes, we deploy electroanalytical methods and ex situ characterization by microscopy, elemental analysis, x-ray photoelectron spectroscopy, x-ray diffraction, and x-ray pair distribution function analyses. Our findings verify that redox processes at the MnOx are accompanied by reversible precipitation/dissolution of crystalline zinc hydroxide sulfate (Zn4(OH)6(SO4)·xH2O), mediated by the more uniformly reactive electrode structure inherent to the CNF scaffold.
We consider pressure-driven flow of an ion-carrying viscous Newtonian fluid through a non-uniformly shaped channel coated with a charged deformable porous layer, as a model for blood flow through microvessels that are lined with an endothelial glycocalyx layer (EGL). The EGL is negatively charged and electrically interacts with ions dissolved in the blood plasma. The focus here is on the interplay between electrochemical effects, and the pressure-driven flow through the microvessel. To analyse these effects we use triphasic mixture theory (TMT) which describes the coupled dynamics of the fluid phase, the elastic EGL, ion transport within the fluid and electric fields within the microvessel. The resulting equations are solved numerically using a coupled boundary–finite element method (BEM-FEM) scheme. However, in the physiological regime considered here, ion concentrations and electric potentials vary rapidly over a thin transitional region (Debye layer) that straddles the lumen–EGL interface, which is difficult to resolve numerically. Accordingly we analyse this region asymptotically, to determine effective jump conditions across the interface for BEM-FEM computations within the bulk EGL/lumen. Our results demonstrate that ion–EGL electrical interactions can influence the near-wall flow, causing it to become reversed. This alters the stresses exerted upon the vessel wall, which has implications for the hypothesised role of the EGL as a transmitter of mechanical signals from the blood flow to the endothelial vessel surface.
We conducted a longitudinal assessment in 466 underweight and 446 normal-weight children aged 6–24 months living in the urban slum of Dhaka, Bangladesh to determine the association between vitamin D and other micronutrient status with upper respiratory tract infection (URI) and acute lower respiratory infection (ALRI). Incidence rate ratios of URI and ALRI were estimated using multivariable generalized estimating equations. Our results indicate that underweight children with insufficient and deficient vitamin D status were associated with 20% and 23–25% reduced risk of URI, respectively, compared to children with sufficient status. Underweight children, those with serum retinol deficiency were at 1·8 [95% confidence interval (CI) 1·4–2·4] times higher risk of ALRI than those with retinol sufficiency. In normal-weight children there were no significant differences between different vitamin D status and the incidence of URI and ALRI. However, normal-weight children with zinc insufficiency and those that were serum retinol deficient had 1·2 (95% CI 1·0–1·5) times higher risk of URI and 1·9 (95% CI 1·4–2·6) times higher risk of ALRI, respectively. Thus, our results should encourage efforts to increase the intake of retinol-enriched food or supplementation in this population. However, the mechanisms through which vitamin D exerts beneficial effects on the incidence of childhood respiratory tract infection still needs further research.
The endothelial glycocalyx layer (EGL) is a macromolecular layer that lines the inner surface of blood vessels. It is believed to serve a number of physiological functions in the microvasculature, including protection of the vessel walls from potentially harmful levels of fluid shear, as a molecular sieve that acts to regulate transendothelial mass transport, and as a transducer of mechanical stress from the vessel lumen. To best fulfil some of its roles, it has been suggested that the EGL redistributes, so that it is thickest at the cell–cell junctions. It has also been suggested that the majority of mechanotransduction occurs through the solid phase of the EGL, rather than via its fluid phase. The difficulties associated with measuring the distribution of the EGL in vivo make these hypotheses difficult to confirm experimentally. Consequently, to gauge the impact of EGL redistribution from a theoretical standpoint, we compute the flow through a porous-lined microvessel, the endothelial surface of which has been informed by confocal microscopy images of a postcapillary venule. Following earlier studies, we model the poroelastohydrodynamics of the EGL using biphasic mixture theory, taking advantage of a recently developed boundary integral representation of these equations to solve the coupled poroelastohydrodynamics using the boundary element method. However, the low permeabilities of the EGL mean that viscous effects are confined to thin layers, thereby also enabling an asymptotic treatment of the dynamics in this limit. In this asymptotic regime, we also consider a two-layer Stokes flow model for the lumen flow to approximate the effect of red blood cells within the lumen. We demonstrate that redistribution of the EGL can have a substantial impact upon microvessel haemodynamics. We also confirm that the bulk of the mechanical stress is indeed carried through the solid phase of the EGL.
A comparative study of the effect of dietary nitrogen (N) content [Low: 11·0; Medium-Low (MLow): 16·7; Medium-High (Mhigh): 23·1; High: 29·2 N g/kg dry matter (DM)] on apparent digestibilities, rumen fermentation and N balance was conducted in coarse wool Tibetan sheep and Gansu Alpine fine-wool sheep at Wushaoling in the northeast of the Qinghai-Tibetan Plateau. It was hypothesized that responses would differ between breeds and that responses would favour Tibetan over fine-wool sheep at low N intakes. Eight wethers [four Tibetan sheep and four fine-wool sheep, 20–24 months old; body weight ± standard deviation was 52 ± 3·2 kg] were used in two concurrent 4 × 4 Latin square designs. Dry matter, organic matter, neutral detergent fibre and acid detergent fibre digestibilities were higher in Tibetan than fine-wool sheep when fed the Low, MLow and High N diets while N retention was higher when the animals were fed the Low and MLow N diets. Tibetan sheep had a higher rumen pH than fine-wool sheep; however, total volatile fatty acids were similar between breeds. Molar proportions of acetate were higher but propionate and butyrate lower in Tibetan than fine-wool sheep. In addition, Tibetan sheep had higher concentrations of ruminal free amino acid-N and soluble protein-N than fine-wool sheep. Plasma and saliva urea-N concentrations were higher in Tibetan than fine-wool sheep when supplied with the Low N diet. It was concluded that Tibetan sheep were better able to cope with low N feed than fine-wool sheep because of the higher N retention and higher DM and fibre digestibilities with Low and MLow diets.
Given the high intake levels of soya and low incidence rates of breast cancer in Asian countries, isoflavones, substances with an oestrogen-like structure occurring principally in soyabeans, are postulated to be cancer protective. In the present study, we examined the association of dietary isoflavone intake with breast cancer risk in 84 450 women (896 in situ and 3873 invasive cases) who were part of the Multiethnic Cohort (Japanese Americans, whites, Latinos, African Americans and Native Hawaiians) with a wide range of soya intake levels. The absolute levels of dietary isoflavone intake estimated from a baseline FFQ were categorised into quartiles, with the highest quartile being further subdivided to assess high dietary intake. The respective intake values for the quartiles (Q1, Q2, Q3, and lower and upper Q4) were 0– < 3·2, 3·2– < 6·7, 6·7– < 12·9, 12·9– < 20·3, and 20·3–178·7 mg/d. After a mean follow-up period of 13 years, hazard ratios (HR) and 95 % CI were calculated using Cox regression models stratified by age and adjusted for known confounders. Linear trends were tested by modelling continuous variables of interest assigned the median value within the corresponding quartile. No statistically significant association was observed between dietary isoflavone intake and overall breast cancer risk (HR for upper Q4 v. Q1: 0·96 (95 % CI 0·85, 1·08); P trend = 0·40). While the test for interaction was not significant (P= 0·14), stratified analyses suggested possible ethnic/racial differences in risk estimates, indicating that higher isoflavone intakes may be protective in Latina, African American and Japanese American women. These results are in agreement with those of previous meta-analyses showing no protection of isoflavones at low intake levels, but suggesting inverse associations in populations consuming high amounts of soya.
The oxidation of CO to CO2 is necessary in the operation of Proton Exchange Membrane Fuel Cells (PEMFCs) since even a small amount of CO that is formed when the PEMFC is operated under ambient conditions is sufficient to poison the Pt catalyst in the electrodes and degrade the performance. Operation using higher loads of Pt catalysts or increasing the purity of the H2 input gas significantly adds to the cost, adversely impacting the commercial development of PEMFCs. We combined graphene oxide (GO) with metallic salts and partially reduced the mixture with sodium borohydride, yielding a metallized form of partially reduced graphene oxide (prGO) platelets that remained in solution. When these platelets were coated on the Nafion membrane of a PEMFC, a 72% increase in the power output was observed, whereas a 62% increase was observed when the membrane was coated with partially reduced graphene oxide without the metallic salts. Results will be presented for AuGO/prGO, PtGO/prGO, and AuPtGO/prGO combinations.
There is growing evidence that many offspring of parents with bipolar disorder (BD) will develop moderate to severe forms of psychopathology during childhood and adolescence, including thought problems. The purpose of this study was to evaluate the developmental progression of thought problems within the context of a family risk study. Repeated assessments of thought problems, spanning approximately 15 years, were conducted in offspring (N = 192 from 98 families) of parents diagnosed with BD (O-BD), unipolar depression (O-UNI), or no significant psychiatric or medical problems (O-WELL). Survival analysis showed that the O-BD group had the greatest estimated probability of developing thought problems over time, followed by O-UNI, and then O-WELL and O-BD exhibiting higher levels of persistence than O-WELL. Parent-reported thought problems in childhood and adolescence predicted a range of problems in young adulthood. Disturbances in reality testing and other atypical behaviors are likely to disrupt progression through important developmental periods and to associate with poor outcomes. These findings are likely relevant to preventing the occurrence or progression of problems in offspring of bipolar parents. The study of thought problems across development represents an important area of continued research in children at risk for development of affective disorders.
The grey matter of the brain contains high levels of the essential nutrient DHA. Although the role of DHA in the developing brain and in dementia has attracted attention, its influence on the brain of the healthy adult has been little considered. A total of 285 young adult females took 400 mg of DHA, in a double-blind, placebo-controlled trial, for 50 d. After 50 d, recently acquired information was more likely to be forgotten by those who had consumed DHA. No significant differences in mood, reaction times, vigilance or visual acuity were found.
Input from molecular phylogenetics in the past five years has substantially altered concepts of systematic relationships among liverworts. While these studies have confirmed the monophyly of phylum Marchantiophyta, they have demonstrated that many previously recognised ranks within the hierarchy are unnatural and in need of modification. Changes in the ranks of suborder and above have been proposed by various workers, but modifications in the circumscription of genera and families are still required. A comprehensive, phylogenetic classification scheme that integrates morphological data with molecular hypotheses is presented. The scheme includes diagnoses and publication citations for all names above the rank of genus. All currently recognised genera are listed alphabetically in their respective families; subfamilies are not indicated. Major modifications and novel alignments of taxa are thoroughly discussed, with pertinent references provided. Jungermanniaceae is redefined and Solenostomataceae fam. nov. is formally described to accommodate some of the genera excluded from it.
Home baseline and laboratory stressor (Trier Social Stress Test for Children) measures of salivary cortisol were obtained from 82 participants (40 girls) aged 9, 11, 13, and 15 years. Measures of pubertal development, self-reported stress, parent reports of child depressive symptoms and fearful temperament, and cardiac measures of sympathetic and parasympathetic activity were also obtained. Significant increases in the home cortisol baselines were found with age and pubertal development. Cortisol stress reactivity differed by age group with 11-year-olds and 13-year-old boys showing blunted reactivity and 9-year-olds, 13-year-old girls, and 15-year-olds showing significant cortisol reactions. Cortisol reactivity correlated marginally with sexual maturation. Measures of sympathetic activity revealed increased sympathetic modulation with age. Higher sympathetic tone was associated with more fearful temperament, whereas greater cortisol reactivity was associated with more anxious and depressed symptoms for girls. The importance of these findings for the hypothesis that puberty-associated increases in hypothalamic–pituitary–adrenal axis activity heightens the risk of psychopathology is discussed.
Animal studies reveal that early deprivation impairs regulation of the hypothalamic–pituitary–adrenocortical (HPA) axis, potentially increasing vulnerability to stressors throughout life. To examine early deprivation effects on basal HPA axis activity in humans, basal cortisol levels were examined in 164 internationally adopted children who had experienced varying degrees of preadoption deprivation. Duration of institutional care, age at adoption, and parent ratings of preadoption neglect indexed a latent factor of Deprived Care. Adoption measures of height and weight standardized to World Health Organisation norms indexed a latent factor of Growth Delay that was viewed as another reflection of deprivation. Cortisol samples were collected 3.3–11.6 years postadoption (Md = 7.3 years) at home on 3 days approximately 30 min after wakeup and before bedtime. Both early a.m. levels and the decrease in cortisol across the day were examined. A structural equation model revealed that preadoption Deprived Care predicted Growth Delay at adoption and Growth Delay predicted higher morning cortisol levels and a larger diurnal cortisol decrease.
Using a combination of satellite sensors, field measurements and satellite-uplinked in situ observing stations, we examine the evolution of several large icebergs drifting east of the Antarctic Peninsula towards South Georgia Island. Three styles of calving are observed during drift: ‘rift calvings’, ‘edge wasting’ and ‘rapid disintegration’. Rift calvings exploit large pre-existing fractures generated in the shelf environment and can occur at any stage of drift. Edge wasting is calving of the iceberg perimeter by numerous small edge-parallel, sliver-shaped icebergs, preserving the general shape of the main iceberg as it shrinks. This process is observed only in areas north of the sea-ice edge. Rapid disintegration, where numerous small calvings occur in rapid succession, is consistently associated with indications of surface melt saturation (surface lakes, firn-pit ponding). Freeboard measurements by ICESat indicate substantial increases in ice-thinning rates north of the sea-ice edge (from <10 m a−1 to >30 m a−1), but surface densification is shown to be an important correction (>2 m freeboard loss before the firn saturates). Edge wasting of icebergs in ‘warm’ surface water (sea-ice-free, >−1.8°C) implies a mechanism based on waterline erosion. Rapid disintegration (‘Larsen B-style’ break-up) is likely due to the effects of surface or saturated-firn water acting on pre-existing crevasses, or on wave- or tidally induced fractures. Changes in microwave backscatter of iceberg firn as icebergs drift into warmer climate and experience increased surface melt suggest a means of predicting when floating ice plates are evolving towards disintegration.
We report on XMM-Newton and Chandra observations of the globular cluster NGC 2808. We detect one quiescent low mass X-ray binary of the 3±1 expected, if these systems are formed through encounters, and we show evidence for the presence of 20±10 bright cataclysmic variables in the core with a luminosity above 4×1031 erg s−1. We also review the specific nature of cataclysmic variables in globular clusters with reference to recent VLT/FORS1 observations of a cataclysmic variable in M 22.