CMS Hospital Value-Based Programs: Refinements Are Needed To Reduce Health Disparities And Improve Outcomes.

Several Centers for Medicare and Medicaid Services (CMS) programs aim to transform how health care is delivered by adjusting Medicare inpatient hospital payments through a system of rewards and penalties based on performance on measures of quality. These programs are the Hospital Readmissions Reduction Program, the Hospital Value-Based Purchasing Program, and the Hospital-Acquired Condition Reduction Program. We analyzed value-based program penalty results for various groups of hospitals across these three programs and assessed the impact of patient and community health equity risk factors on hospital penalties. We found statistically significant positive relationships between hospital penalties and several factors that affect hospital performance but that hospitals cannot control-namely, medical complexity (as measured by Hierarchical Condition Categories scores), uncompensated care, and the portion of hospital catchment area populations who live alone. Moreover, these environmental conditions can be worse for hospitals that operate in areas with historically underserved populations. This suggests that the CMS programs might not adequately account for health equity factors at the community level. Refinements to these programs (including an explicit incorporation of patient and community health equity risk factors) and continued monitoring will help ensure that the programs work as intended in a fair and equitable fashion.

Planetary Mapping Using Deep Learning: A Method to Evaluate Feature Identification Confidence Applied to Habitats in Mars-Analog Terrain.

The goals of Mars exploration are evolving beyond describing environmental habitability at global and regional scales to targeting specific locations for biosignature detection, sample return, and eventual human exploration. An increase in the specificity of scientific goals-from follow the water to find the biosignatures-requires parallel developments in strategies that translate terrestrial Mars-analog research into confident identification of rover-explorable targets on Mars. Precisely how to integrate terrestrial, ground-based analyses with orbital data sets and transfer those lessons into rover-relevant search strategies for biosignatures on Mars remains an open challenge. Here, leveraging small Unmanned Aerial System (sUAS) technology and state-of-the-art fully convolutional neural networks for pixel-wise classification, we present an end-to-end methodology that applies Deep Learning to map geomorphologic units and quantify feature identification confidence. We used this method to assess the identification confidence of rover-explorable habitats in the Mars-analog Salar de Pajonales over a range of spatial resolutions and found that spatial resolutions two times better than are available from Mars would be necessary to identify habitats in this study at the 1-σ (85%) confidence level. The approach we present could be used to compare the identifiability of habitats across Mars-analog environments and focus Mars exploration from the scale of regional habitability to the scale of specific habitats. Our methods could also be adapted to map dome- and ridge-like features on the surface of Mars to further understand their origin and astrobiological potential.

Mass fluxes of dissolved arsenic discharging to the Meghna River are sufficient to account for the mass of arsenic in riverbank sediments.

Shallow (<30 m) reducing groundwater commonly contains abundant dissolved arsenic (As) in Bangladesh. We hypothesize that dissolved As in iron (Fe)-rich groundwater discharging to rivers is trapped onto Fe(III)-oxyhydroxides which precipitate in shallow riverbank sediments under the influence of tidal fluctuations. Therefore, the goal of this study is to compare the calculated mass of sediment-bound As that would be sequestered from dissolved groundwater As that discharges through riverbanks of the Meghna River to the observed mass of As trapped within riverbank sediments. To calculate groundwater discharge, a Boussinesq aquifer analytical groundwater flow model was developed and constrained by cyclical seasonal fluctuations in hydraulic heads and river stages observed at three sites along a 13 km reach in central Bangladesh. At all sites, groundwater discharges to the river year-round but most of it passes through an intertidal zone created by ocean tides propagating upstream from the Bay of Bengal in the dry season. The annualized groundwater discharge per unit width at the three sites ranges from 173 to 891 m2/yr (average 540 m2/yr). Assuming that riverbanks have been stable since the Brahmaputra River avulsed far away from this area 200 years ago and dissolved As is completely trapped within riverbank sediments, the mass of accumulated sediment As can be calculated by multiplying groundwater discharge by ambient aquifer As concentrations measured in 1969 wells. Across all sites, the range of calculated sediment As concentrations in the riverbank is 78-849 mg/kg, which is higher than the observed concentrations (17-599 mg/kg). This discovery supports the hypothesis that the dissolved As in groundwater discharge to the river is sufficient to account for the observed buried deposits of As along riverbanks.

Constraints on the Metabolic Activity of Microorganisms in Atacama Surface Soils Inferred from Refractory Biomarkers: Implications for Martian Habitability and Biomarker Detection.

Dryness is one of the main environmental challenges to microbial survival. Understanding the threshold of microbial tolerance to extreme dryness is relevant to better constrain the environmental limits of life on Earth and critically evaluate long-term habitability models of Mars. Biomolecular proxies for microbial adaptation and growth were measured in Mars-like hyperarid surface soils in the Atacama Desert that experience only a few millimeters of precipitation per decade, and in biologically active soils a few hundred kilometers away that experience two- to fivefold more precipitation. Diversity and abundance of lipids and other biomolecules decreased with increasing dryness. Cyclopropane fatty acids (CFAs), which are indicative of adaptive response to environmental stress and growth in bacteria, were only detected in the wetter surface soils. The ratio of trans to cis isomers of an unsaturated fatty acid, another bacterial stress indicator, decreased with increasingly dry conditions. Aspartic acid racemization ratios increased from 0.01 in the wetter soils to 0.1 in the driest soils, which is indicative of racemization rates comparable to de novo biosynthesis over long timescales (∼10,000 years). The content and integrity of stress proteins profiled by immunoassays were additional indicators that biomass in the driest soils is not recycled at significant levels. Together, our results point to minimal or no in situ microbial growth in the driest surface soils of the Atacama, and any metabolic activity is likely to be basal for cellular repair and maintenance only. Our data add to a growing body of evidence that the driest Atacama surface soils represent a threshold for long-term habitability (i.e., growth and reproduction). These results place constraints on the potential for extant life on the surface of Mars, which is 100-1000 times drier than the driest regions in the Atacama. Key Words: Atacama Desert-Dryness-Growth-Habitability-Biomarker-Mars. Astrobiology 18, 955-966.

Recreational Drug and Psychosocial Profile in Chronic Hepatitis C Patients Seeking Antiviral Therapy.

BACKGROUND AND AIMS: Practitioners treating hepatitis C (HCV) provide healthcare to a special population with high rates of substance abuse and psychiatric disorders. We investigated the psychosocial profile in HCV patients and tested what variables affect commencement of antiviral therapy. MATERIAL AND METHODS: Recreational drug use (RDU), marijuana (THC), alcohol use, and psychiatric history were initially investigated with a questionnaire prior to history and physical. Following an educational intervention, we reinterrogated patients for RDU and THC use, and revision of initial statement was documented. Variables affecting commencement of antiviral therapy were analysed with logistic regression. RESULTS: Out of 153 patients, 140 (92%) answered the questionnaire. Intervention increased total yield by 6%, however, 39% (11/28) of those initially denying use revised their statement. Drug screening identified 9 more patients with RDU/THC use. Half of patients consuming alcohol were heavy drinkers, and psychiatric disease was identified in 54%. Only 73 (48%) of 139 patients eligible for antivirals received treatment. Multivariable analysis revealed that younger patients (OR = 1.04, 95% CI 1.01-1.08), and those testing positive on drug screen (OR = 0.41, 95% CI 0.19-0.92) were less likely to be treated. Denial by insurance and loss to follow-up were the most common reasons for not starting antiviral treatment. CONCLUSION: Substance abuse is highly prevalent among HCV patients, and it is difficult to tell prior from current users. Integral care of HCV patients should include a diligent screen for substance abuse and rehabilitation referral, aiming to increase the pool of patients eligible for antiviral therapy. This can only be achieved through a multidisciplinary approach.

Microbial Biomarker Transition in High-Altitude Sinter Mounds From El Tatio (Chile) Through Different Stages of Hydrothermal Activity.

Geothermal springs support microbial communities at elevated temperatures in an ecosystem with high preservation potential that makes them interesting analogs for early evolution of the biogeosphere. The El Tatio geysers field in the Atacama Desert has astrobiological relevance due to the unique occurrence of geothermal features with steep hydrothermal gradients in an otherwise high altitude, hyper-arid environment. We present here results of our multidisciplinary field and molecular study of biogeochemical evidence for habitability and preservation in silica sinter at El Tatio. We sampled three morphologically similar geyser mounds characterized by differences in water activity (i.e., episodic liquid water, steam, and inactive geyser lacking hydrothermal activity). Multiple approaches were employed to determine (past and present) biological signatures and dominant metabolism. Lipid biomarkers indicated relative abundance of thermophiles (dicarboxylic acids) and sulfate reducing bacteria (branched carboxylic acids) in the sinter collected from the liquid water mound; photosynthetic microorganisms such as cyanobacteria (alkanes and isoprenoids) in the steam sinter mound; and archaea (squalane and crocetane) as well as purple sulfur bacteria (cyclopropyl acids) in the dry sinter from the inactive geyser. The three sinter structures preserved biosignatures representative of primary (thermophilic) and secondary (including endoliths and environmental contaminants) microbial communities. Sequencing of environmental 16S rRNA genes and immuno-assays generally corroborated the lipid-based microbial identification. The multiplex immunoassays and the compound-specific isotopic analysis of carboxylic acids, alkanols, and alkanes indicated that the principal microbial pathway for carbon fixation in the three sinter mounds was through the Calvin cycle, with a relative larger contribution of the reductive acetyl-CoA pathway in the dry system. Other inferred metabolic traits varied from the liquid mound (iron and sulfur chemistry), to the steam mound (nitrogen cycle), to the dry mound (perchlorate reduction). The combined results revealed different stages of colonization that reflect differences in the lifetime of the mounds, where primary communities dominated the biosignatures preserved in sinters from the still active geysers (liquid and steam mounds), in contrast to the surviving metabolisms and microbial communities at the end of lifetime of the inactive geothermal mound.

The Impact of the Degree of Aquifer Confinement and Anisotropy on Tidal Pulse Propagation.

Oceanic tidal fluctuations which propagate long distances up coastal rivers can be exploited to constrain hydraulic properties of riverbank aquifers. These estimates, however, may be sensitive to degree of aquifer confinement and aquifer anisotropy. We analyzed the hydraulic properties of a tidally influenced aquifer along the Meghna River in Bangladesh using: (1) slug tests combined with drilling logs and surface resistivity to estimate Transmissivity (T); (2) a pumping test to estimate T and Storativity (S) and thus Aquifer Diffusivity (DPT ); and (3) the observed reduction in the amplitude and velocity of a tidal pulse to calculate D using the Jacob-Ferris analytical solution. Average Hydraulic Conductivity (K) and T estimated with slug tests and borehole lithology were 27.3 m/d and 564 m2 /d, respectively. Values of T and S determined from the pumping test ranged from 400 to 500 m2 /d and 1 to 5 × 10-4 , respectively with DPT ranging from 9 to 40 × 105 m2 /d. In contrast, D estimated from the Jacob-Ferris model ranged from 0.5 to 9 × 104 m2 /d. We hypothesized this error resulted from deviations of the real aquifer conditions from those assumed by the Jacob-Ferris model. Using a 2D numerical model tidal pulses were simulated across a range of conditions and D was calculated with the Jacob-Ferris model. Moderately confined (Ktop /Kaquifer < 0.01) or anisotropic aquifers (Kx /Kz > 10) yield D within a factor of 2 of the actual value. The order of magnitude difference in D between pumping test and Jacob-Ferris model at our site argues for little confinement or anisotropy.

Perceptual asymmetries influence task choice: the effect of lateralised presentation of hierarchical stimuli.

The current study examined how hemispheric asymmetries in perceptual processing affect control processes associated with voluntary task choice during multitask behaviour. In a voluntary task-switching paradigm, where participants are free to choose which task to perform on each trial, participants identified either the global-or local-level features of hierarchical stimuli presented to either the left or right visual field. Hemispheric asymmetries in perception of lateralised hierarchical stimuli were evident in reaction times. Importantly, participants were more likely to categorize the stimulus in line with the processing efficiency of the hemisphere to which it was initially presented: the global task for left visual field presentation and the local task for right visual field presentation. Perceptual processing characteristics influence control processes associated with task choice in multitask environments.

Chronic stress increases pituitary adenylate cyclase-activating peptide (PACAP) and brain-derived neurotrophic factor (BDNF) mRNA expression in the bed nucleus of the stria terminalis (BNST): roles for PACAP in anxiety-like behavior.

Exposure to chronic stress has been argued to produce maladaptive anxiety-like behavioral states, and many of the brain regions associated with stressor responding also mediate anxiety-like behavior. Pituitary adenylate cyclase activating polypeptide (PACAP) and its specific G protein-coupled PAC(1) receptor have been associated with many of these stress- and anxiety-associated brain regions, and signaling via this peptidergic system may facilitate the neuroplasticity associated with pathological affective states. Here we investigated whether chronic stress increased transcript expression for PACAP, PAC(1) receptor, brain-derived neurotrophic factor (BDNF), and tyrosine receptor kinase B (TrkB) in several nuclei. In rats exposed to a 7 days chronic variate stress paradigm, chronic stress enhanced baseline startle responding induced by handling and exposure to bright lights. Following chronic stress, quantitative transcript assessments of brain regions demonstrated dramatic increases in PACAP and PAC(1) receptor, BDNF, and TrkB receptor mRNA expression selectively in the dorsal aspect of the anterolateral bed nucleus of the stria terminalis (dBNST). Related vasoactive intestinal peptide (VIP) and VPAC receptor, and other stress peptide transcript levels were not altered compared to controls. Moreover, acute PACAP38 infusion into the dBNST resulted in a robust dose-dependent anxiogenic response on baseline startle responding that persisted for 7 days. PACAP/PAC(1) receptor signaling has established trophic functions and its coordinate effects with chronic stress-induced dBNST BDNF and TrkB transcript expression may underlie the maladaptive BNST remodeling and plasticity associated with anxiety-like behavior.

Halorubrum alkaliphilum sp. nov., a novel haloalkaliphile isolated from a soda lake in Xinjiang, China.

A novel haloalkaliphilic archaeon, strain DZ-1T, was isolated from a soda lake in Xinjiang, China. The taxonomy of strain DZ-1T was studied by polyphasic methods. According to 16S rRNA gene sequence similarity, strain DZ-1T was phylogenetically related to Halorubrum tibetense (97.5 %), Halorubrum vacuolatum (95.7 %) and Halorubrum saccharovorum (95.9 %). Strain DZ-1T was able to grow at 20-44 degrees C and was also physiologically different from the above-mentioned species with respect to assimilation of sugars and utilization of organic acids. The DNA G+C content of strain DZ-1T was 62.1 mol% (Tm). The DNA-DNA relatedness of strain DZ-1T to H. tibetense and H. vacuolatum was 22 and 13 %, respectively. It was concluded that strain DZ-1T represents a novel species of the genus Halorubrum, for which the name Halorubrum alkaliphilum (type strain, DZ-1T=AS 1.3528T=JCM 12358T) is proposed.