Research confirms that the mental health burdens following community-wide disasters are extensive, with pervasive impacts noted in individuals and families. It is clear that child disaster outcomes ...are worst among children of highly distressed caregivers, or those caregivers who experience their own negative mental health outcomes from the disaster. The current study used path analysis to examine concurrent patterns of parents’ (n = 420) experience from a national sample during the early months of the U.S. COVID-19 pandemic. The results of a multi-group path analysis, organized by parent gender, indicate good fit to the data X
2
(10) = 159.04, p < .01. Results indicate significant linkages between parents’ caregiver burden, mental health, and perceptions of children’s stress; these in turn are significantly linked to child-parent closeness and conflict, indicating possible spillover effects for depressed parents and compensatory effects for anxious parents. The impact of millions of families sheltering in place during the COVID-19 pandemic for an undefined period of time may lead to unprecedented impacts on individuals’ mental health with unknown impacts on child-parent relationships. These impacts may be heightened for families whose caregivers experience increased mental health symptoms, as was the case for fathers in the current sample.
The ultimate origin of water in the Earth's hydrosphere is in the deep Earth--the mantle. Theory and experiments have shown that although the water storage capacity of olivine-dominated shallow ...mantle is limited, the Earth's transition zone, at depths between 410 and 660 kilometres, could be a major repository for water, owing to the ability of the higher-pressure polymorphs of olivine--wadsleyite and ringwoodite--to host enough water to comprise up to around 2.5 per cent of their weight. A hydrous transition zone may have a key role in terrestrial magmatism and plate tectonics, yet despite experimental demonstration of the water-bearing capacity of these phases, geophysical probes such as electrical conductivity have provided conflicting results, and the issue of whether the transition zone contains abundant water remains highly controversial. Here we report X-ray diffraction, Raman and infrared spectroscopic data that provide, to our knowledge, the first evidence for the terrestrial occurrence of any higher-pressure polymorph of olivine: we find ringwoodite included in a diamond from Juína, Brazil. The water-rich nature of this inclusion, indicated by infrared absorption, along with the preservation of the ringwoodite, is direct evidence that, at least locally, the transition zone is hydrous, to about 1 weight per cent. The finding also indicates that some kimberlites must have their primary sources in this deep mantle region.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Electrode potential–pH (Pourbaix) diagrams provide a phase map of the most stable compounds of a metal, its corrosion products, and associated ions in solution. The utility of these phase diagrams is ...that they enable the assessment of electrochemical stabilities, for example, of Ni metal and its derived oxides, hydroxides, and oxyhydroxides, against corrosion in aqueous environments. Remarkably, the Ni Pourbaix diagrams reported over the last 50 years are largely inconsistent with various electrochemical observations, which may be attributed to inaccurate experimental free energies of formation (Δf G) for the complex Ni-based compounds used in producing the available diagrams. Here we show that state-of-the-art density-functional theory (DFT) can be used to obtain accurate Δf G values, which lead to Ni Pourbaix diagrams that are more consistent with direct electrochemical experiments: Electrochemical impedance spectroscopy and surface-enhanced Raman spectroscopy are used to characterize the electrochemical stabilities of NiO and Ni(OH)2 formed on Ni, demonstrating the reliability in correction-free first-principles based Pourbaix diagrams. Our results show the importance in applying modern density functionals in combination with experimental advances in aqueous environment compound identification for assessing electrochemical phase stability of materials, which will be useful for the design, synthesis, and selection of corrosion-resistant metals, photoabsorbers, and photocatalytic materials.
Aims: To improve our understanding of the survival and splash‐mediated transfer of zoonotic agents and faecal indicator bacteria introduced into soils used for crop cultivation via contaminated ...irrigation waters. Methods and Results: Zoonotic agents and an Escherichia coli marker bacterium were inoculated into borehole water, which was applied to two different soil types in early‐, mid‐ and late summer. Decline of the zoonotic agents was influenced by soil type. Marker bacteria applied to columns of two soil types in irrigation water did not concentrate at the surface of the soils. Decline of zoonotic agents at the surface was influenced by soil type and environmental conditions. Typically, declines were rapid and bacteria were not detectable after 5 weeks. Selective agar strips were used to determine that the impact of water drops 24–87 μl could splash marker bacteria from soil surfaces horizontal distances of at least 25 cm and heights of 20 cm. Conclusions: Soil splash created by rain‐sized water droplets can transfer enteric bacteria from soil to ready‐to‐eat crops. Persistence of zoonotic agents was reduced at the hottest part of the growing season when irrigation is most likely. Significance and Impact of the Study: Soil splash can cause crop contamination. We report the penetration depths and seasonally influenced declines of bacteria applied in irrigation water into two soil types.
To describe longitudinal rates of change of neuroretinal parameters in patients with glaucoma and healthy controls, and to evaluate the influence of covariates.
Prospective longitudinal study.
...Treated patients with glaucoma (n = 192) and healthy controls (n = 37).
Global disc margin-based neuroretinal rim area (DMRA) was measured with confocal scanning laser tomography, while Bruch's membrane opening-minimum rim width (BMO-MRW), BMO area (BMOA), and peripapillary retinal nerve fiber layer thickness (RNFLT) were measured with optical coherence tomography at 6-month intervals. Individual rates of change were estimated with ordinary least-squares regression, and linear mixed effects modeling was used to estimate the average rate of change and differences between the groups, and to evaluate the effects of baseline measurement and baseline age on rates of change.
Rates of change for each parameter.
Subjects were followed for a median (range) of 4 (2-6) years. The proportion of controls who had significant reduction of neuroretinal parameters was 35% for BMO-MRW, 31% for RNFLT, and 11% for DMRA. The corresponding figures for patients with glaucoma were not statistically different (42%, P = 0.45; 31%, P = 0.99; 14%, P = 0.99, respectively). Controls had a significant reduction of BMO-MRW (mean: -1.92 μm/year, P < 0.01) and RNFLT (mean: -0.44 μm/year, P = 0.01), but not DMRA (mean: -0.22×10(-2) mm(2)/year, P = 0.41). After adjusting for covariates, patients with glaucoma had faster, but not statistically different, rates of deterioration compared with controls, by -1.26 μm/year (P = 0.07) for BMO-MRW, -0.40 μm/year (P = 0.11) for RNFLT, and -0.38×10(-2) mm(2)/year (P = 0.23) for DMRA. Baseline BMO-MRW and RNFLT significantly influenced the respective rates of change, with higher baseline values relating to faster reductions. Older age at baseline was associated with a slower reduction in rates of BMO-MRW. Reductions in intraocular pressure were related to increases in BMO-MRW and DMRA. There was a tendency for BMOA to decrease over time (-0.38×10(-2) mm(2)/year; P = 0.04).
Age-related loss of neuroretinal parameters may explain a large proportion of the deterioration observed in treated patients with glaucoma and should be carefully considered in estimating rates of change.
A variety of organisms have evolved mechanisms to detect and respond to light, in which the response is mediated by protein structural changes after photon absorption. The initial step is often the ...photoisomerization of a conjugated chromophore. Isomerization occurs on ultrafast time scales and is substantially influenced by the chromophore environment. Here we identify structural changes associated with the earliest steps in the trans-to-cis isomerization of the chromophore in photoactive yellow protein. Femtosecond hard x-ray pulses emitted by the Linac Coherent Light Source were used to conduct time-resolved serial femtosecond crystallography on photoactive yellow protein microcrystals over a time range from 100 femtoseconds to 3 picoseconds to determine the structural dynamics of the photoisomerization reaction.
To evaluate the possible role of the default mode network (DMN) in consciousness and assess the diagnostic or prognostic potential of DMN connectivity measures in the assessment of a patient group ...lacking cognitive awareness.
DMN connectivity was established using independent component analysis of resting-state fMRI data in patients with reversible (n = 2) and irreversible (n = 11) coma following cardiac arrest and compared to healthy controls (n = 12).
A present and intact DMN was observed in controls and those patients who subsequently regained consciousness, but was disrupted in all patients who failed to regain consciousness.
The results suggest that the DMN is necessary but not sufficient to support consciousness. Clinically, DMN connectivity may serve as an indicator of the extent of cortical disruption and predict reversible impairments in consciousness.
To determine the response of the anterior lamina cribrosa and prelaminar tissue to acute elevation of intraocular pressure (IOP) in glaucoma patients and healthy subjects.
Prospective case-control ...series.
Patients with open-angle glaucoma (n = 12; mean age ± standard deviation SD, 66.8 ± 6.0 years), age-matched healthy controls (n = 12; mean age ± SD, 67.1 ± 6.2 years), and young controls (n = 12; mean age ± SD, 36.1 ± 11.7 years).
One eye was imaged with spectral-domain optical coherence tomography to obtain 12 high-resolution radial scans centered on the optic disc. Imaging was repeated at precisely the same locations with an ophthalmodynamometer held perpendicular to the globe via the inferior lid to raise the IOP. A line joining Bruch's membrane opening in 4 radial scans was used as reference in the baseline and elevated IOP images. The vertical distance from the reference line to the anterior prelaminar tissue surface and anterior laminar surface was measured at equidistant points along the reference line in the 2 sets of images. The difference between the 2 sets of corresponding measurements were used to determine laminar displacement (LD) and prelaminar tissue displacement (PTD).
Laminar displacement and PTD.
Intraocular pressure elevation among patients, age-matched controls, and young controls was similar (mean ± SD, 12.4 ± 3.2 mmHg). The mean ± SD LD and PTD were 0.5 ± 3.3 μm and 15.7 ± 15.5 μm, respectively. The LD was not statistically different from 0 (P = 0.366), but PTD was (P < 0.001). The mean ± SD LD was similar among the groups (-0.5 ± 3.7 μm, 0.2 ± 2.0 μm, and 2.0 ± 3.6 μm, respectively; P = 0.366), whereas the mean ± SD PTD was different (6.8 ± 13.7 μm, 20.8 ± 17.5 μm, and 19.6 ± 11.8 μm, respectively; P = 0.045). In all subjects, the PTD was greater than LD. In multivariate regression analyses, LD was negatively associated with optic disc size (P = 0.007), whereas PTD was positively associated with the degree of IOP elevation (P = 0.013).
In glaucoma patients and controls, the anterior laminar surface is noncompliant to acute IOP elevation. Acute optic disc surface changes represent compression of prelaminar tissue and not laminar displacement.
Neuroretinal rim assessment based on the clinical optic disc margin (DM) lacks a sound anatomic basis for 2 reasons: (1) The DM is not reliable as the outer border of rim tissue because of clinically ...and photographically invisible extensions of Bruch's membrane (BM) inside the DM and (2) nonaccountability of rim tissue orientation in the optic nerve head (ONH). The BM opening-minimum rim width (BMO-MRW) is a parameter that quantifies the rim from its true anatomic outer border, BMO, and accounts for its variable orientation. We report the diagnostic capability of BMO-MRW.
Case control.
Patients with open-angle glaucoma (n = 107) and healthy controls (n = 48).
Spectral-domain optical coherence tomography (SD-OCT) with 24 radial and 1 circumpapillary B-scans, centered on the ONH, and confocal scanning laser tomography (CSLT) were performed. The internal limiting membrane (ILM) and BMO were manually segmented in each radial B-scan. Three SD-OCT parameters were computed globally and sectorally: (1) circumpapillary retinal nerve fiber layer thickness (RNFLT); (2) BMO-horizontal rim width (BMO-HRW), the distance between BMO and ILM in the BMO reference plane; and (3) BMO-MRW, the minimum distance between BMO and ILM. Moorfields Regression Analysis (MRA) with CLST was performed globally and sectorally to yield MRA1 and MRA2, where "borderline" was classified as normal and abnormal, respectively.
Sensitivity, specificity, and likelihood ratios (LRs) for positive and negative test results (LR+/LR-).
The median (interquartile range) age and mean deviation of patients and controls were 69.9 (64.3-76.9) and 65.0 (58.1-74.3) years and -3.92 (-7.87 to -1.62) and 0.33 (-0.32 to 0.98) dB, respectively. Globally, BMO-MRW yielded better diagnostic performance than the other parameters. At 95% specificity, the sensitivity of RNFLT, BMO-HRW, and BMO-MRW was 70%, 51%, and 81%, respectively. The corresponding LR+/LR- was 14.0/0.3, 10.2/0.5, and 16.2/0.2. Sectorally, at 95% specificity, the sensitivity of RNFLT ranged from 31% to 59%, of BMO-HRW ranged from 35% to 64%, and of BMO-MRW ranged from 54% to 79%. Globally and in all sectors, BMO-MRW performed better than MRA1 or MRA2.
The higher sensitivity at 95% specificity in early glaucoma of BMO-MRW compared with current BMO methods is significant, indicating a new structural marker for the detection and risk profiling of glaucoma.
Short arginine-rich proteins called protamines mediate the near crystalline DNA packaging in most vertebrate sperm cells. Protamines are synthesized during spermiogenesis and condense the paternal ...genome into a transcriptionally inactive state in late-stage spermatids. Protamines from eutherian mammals, including bulls and humans, also contain multiple cysteine residues that form intra- and interprotamine sulfur-sulfur bonds during the final stages of sperm maturation. Although the cross-linked protamine network is known to stabilize the resulting nucleoprotamine structure, little is known about the role of disulfide bonds on DNA condensation in the mammalian sperm. Using small angle x-ray scattering, we show that isolated bull nuclei achieve slightly lower DNA packing densities compared to salmon nuclei despite salmon protamine lacking cysteine residues. Surprisingly, reduction of the intermolecular sulfur-sulfur bonds of bull protamine results in tighter DNA packing. Complete reduction of the intraprotamine disulfide bonds ultimately leads to decondensation, suggesting that disulfide-mediated secondary structure is also critical for proper protamine function. Lastly, comparison of multiple bull collections showed some to have aberrant x-ray scattering profiles consistent with incorrect disulfide bond formation. Together, these observations shed light on the biological functions of disulfide linkages for in vivo DNA packaging in sperm chromatin.
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