Caddisflies (Trichoptera) of the Buffalo National River, Arkansas

We report 106 species of caddisflies (Trichoptera) representing 44 genera and 16 families that were collected across 50 sampling sites in the Buffalo River watershed. The species collected represent about 45% of the known Interior Highlands caddisfly fauna. The most speciose families collected were the Hydroptilidae (30), Leptoceridae (21), and Hydropsychidae (17). Two species found during this study, Paduniella nearctica and Ochrotrichia contorta, are listed as species of special concern in the state of Arkansas due to their relative rarity. Similarity analysis values among collection sites ranged from 9% to 77%. Seriation analysis of caddisfly genera and species showed that most are distributed throughout the entire Buffalo National River but some are restricted to either the upper or lower river or its tributaries. This represents the first comprehensive survey of caddisflies completed for the Buffalo National River

Feature-tracking-based strain analysis : a comparison of tracking algorithms

Purpose: Optical flow feature-tracking (FT) strain assessment is increasingly being employed scientifically and clinically. Several software packages, employing different algorithms, enable computation of FT-derived strains. The aim of this study is to investigate the impact of the underlying algorithm on the validity and robustness of FT-derived strain results. Material and methods: CSPAMM and SSFP cine sequences were acquired in 30 subjects (15 patients with aortic stenosis and associated secondary hypertrophic cardiomyopathy, and 15 controls) in identical midventricular short-axis locations. Global peak systolic circumferential strain (PSCS) was calculated using tagging and feature-tracking software with different algorithms (non-rigid, elastic image registration, and blood myocardial border tracing). Intermodality agreement and intra- as well inter-observer variability were assessed. Results: Intermodality/inter-algorithm comparison for global PSCS using Friedman’s test revealed statistically significant differences (tagging vs. blood myocardial border tracing algorithm). Intermodality assessment revealed the highest correlation between tagging and non-rigid, elastic image registration (r = 0.84), while correlation between tagging and blood myocardial border tracing (r = 0.36) and between the two feature-tracking software packages (r = 0.5) were considerably lower. Conclusions: The type of algorithm employed during feature-tracking strain assessment has a significant impact on the results. The non-rigid, elastic image registration algorithm produces more precise and reproducible results than the blood myocardium tracing algorithm

Chronic mild stress alters the somatostatin receptors in the rat brain

RATIONALE: The involvement of somatostatin (SST) and its receptors in the pathophysiology of depression and stress has been evidenced by numerous studies. OBJECTIVES: The purpose of the present study was to find whether chronic mild stress (CMS), an animal model of depression, affects the SST receptors in the rat brain and pituitary, as well as the level of SST in plasma. METHODS: In CMS model, rats were subjected to 2 weeks of stress and behaviorally characterized using the sucrose consumption test into differently reacting groups based on their response to stress, i.e., stress-reactive (anhedonic), stress-non-reactive (resilient), and invert-reactive rats (characterized by excessive sucrose intake). We measured specific binding of [(125)I]Tyr(3)-Octreotide, expression of mRNA encoding sst2R receptors in the rat brains, expression of SST and its receptors in rat pituitary, and the level of SST in the plasma. RESULTS: The obtained results show decreases in binding of [(125)I]Tyr(3)-Octreotide in most of rat brain regions upon CMS and no significant differences between three stressed groups of animals, except for significant up-regulation of sst2 receptor in medial habenula (MHb) in the stress-reactive group. In the same group of animals, significant increase in plasma SST level was observed. CONCLUSIONS: There are two particularly sensitive sites distinguishing the response to stress in CMS model. In the brain, it is MHb, while on the periphery this predictor is SST level in plasma. These changes may broaden an understanding of the mechanisms involved in the stress response and point to the intriguing role of MHb

Rapid early Holocene deglaciation of the Laurentide ice sheet

Author Posting. © Nature Publishing Group, 2008. This is the author's version of the work. It is posted here by permission of Nature Publishing Group for personal use, not for redistribution. The definitive version was published in Nature Geoscience 1 (2008): 620-624, doi:10.1038/ngeo285.The early Holocene deglaciation of the Laurentide Ice Sheet (LIS) is the most recent and best constrained disappearance of a large Northern Hemisphere ice sheet. Its demise is a natural experiment for assessing rates of ice sheet decay and attendant contributions to sea level rise. Here we demonstrate with terrestrial and marine records that the final LIS demise occurred in two stages of rapid melting from ~9.0- 8.5 and 7.6-6.8 kyr BP with the LIS contributing ~1.3 and 0.7 cm yr-1 to sea level rise, respectively. Simulations using a fully coupled atmosphere-ocean general circulation model suggest that increased ablation from enhanced early Holocene boreal summer insolation may have been the predominant cause of the LIS contributions to sea level rise. Although the boreal summer surface radiative forcing of early Holocene LIS retreat is twice that of projections for 2100 C.E. greenhouse gas radiative forcing, the associated summer surface air temperature increase is the same. The geologic evidence for rapid LIS retreat under a comparable forcing provides a prehistoric precedent for a possible large negative mass balance response of the Greenland Ice Sheet by the end of the coming century.This research was funded by National Science Foundation grants ATM-05-01351 & ATM-05-01241 to D.W.O. & G.A.S., start-up funds from the University of Wisconsin-Madison and a Woods Hole Oceanographic Institution Postdoctoral Scholarship to A.E.C., and the Woods Hole Oceanographic Institution's Ocean and Climate Change Institute (D.W.O. & R.E.C.)

Laurentide ice-sheet instability during the last deglaciation

Changes in the amount of summer incoming solar radiation (insolation) reaching the Northern Hemisphere are the underlying pacemaker of glacial cycles. However, not all rises in boreal summer insolation over the past 800,000 years resulted in deglaciation to present-day ice volumes, suggesting that there may be a climatic threshold for the disappearance of land-based ice. Here we assess the surface mass balance stability of the Laurentide ice sheet—the largest glacial ice mass in the Northern Hemisphere—during the last deglaciation (24,000 to 9,000 years ago). We run a surface energy balance model with climate data from simulations with a fully coupled atmosphere–ocean general circulation model for key time slices during the last deglaciation. We find that the surface mass balance of the Laurentide ice sheet was positive throughout much of the deglaciation, and suggest that dynamic discharge was mainly responsible for mass loss during this time. Total surface mass balance became negative only in the early Holocene, indicating the transition to a new state where ice loss occurred primarily by surface ablation. We conclude that the Laurentide ice sheet remained a viable ice sheet before the Holocene and began to fully deglaciate only once summer temperatures and radiative forcing over the ice sheet increased by 6–7 °C and 16–20 W m⁻², respectively, relative to full glacial conditions

Techniques for modelling and verifying railway interlockings

We describe a novel framework for modelling railway interlockings which has been developed in conjunction with railway engineers. The modelling language used is CSP(Formula presented.)B. Beyond the modelling we present a variety of abstraction techniques which make the analysis of medium- to large-scale networks feasible. The paper notably introduces a covering technique that allows railway scheme plans to be decomposed into a set of smaller scheme plans. The finitisation and topological abstraction techniques are extended from previous work and are given formal foundations. All three techniques are applicable to other modelling frameworks besides CSP(Formula presented.)B. Being able to apply abstractions and simplifications on the domain model before performing model checking is the key strength of our approach. We demonstrate the use of the framework on a real-life, medium-size scheme plan

Mechanism of mucosal permeability enhancement of CriticalSorb® (Solutol® HS15) investigated In Vitro in cell cultures.

Purpose CriticalSorb™, with the principal component Solutol® HS15, is a novel mucosal drug delivery system demonstrated to improve the bioavailability of selected biotherapeutics. The intention of this study is to elucidate mechanism(s) responsible for the enhancement of trans-mucosal absorption of biological drugs by Solutol® HS15. Methods Micelle size and CMC of Solutol® HS15 were determined in biologically relevant media. Polarised airway Calu-3 cell layers were used to measure the permeability of a panel of biological drugs, and to assess changes in TEER, tight junction and F-actin morphology. The rate of cell endocytosis was measured in vitro in the presence of Solutol® HS15 using a membrane probe, FM 2–10. Results This work initially confirms surfactant-like behaviour of Solutol® HS15 in aqueous media, while subsequent experiments demonstrate that the effect of Solutol® HS15 on epithelial tight junctions is different from a ‘classical’ tight junction opening agent and illustrate the effect of Solutol® HS15 on the cell membrane (endocytosis rate) and F-actin cytoskeleton. Conclusion Solutol® HS15 is the principle component of CriticalSorb™ that has shown an enhancement in permeability of medium sized biological drugs across epithelia. This study suggests that its mechanism of action arises primarily from effects on the cell membrane and consequent impacts on the cell cytoskeleton in terms of actin organisation and tight junction opening

Multisite clinical validation of isothermal amplification-based SARS-CoV-2 detection assays using different sampling strategies

Isothermal amplification-based tests have been introduced as rapid, low-cost, and simple alternatives to real-time reverse transcriptase PCR (RT-PCR) tests for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) detection. The clinical performance of two isothermal amplification-based tests (Atila Biosystems iAMP coronavirus disease of 2019 [COVID-19] detection test and OptiGene COVID-19 direct plus RT-loop-mediated isothermal amplification [LAMP] test) was compared with that of clinical RT-PCR assays using different sampling strategies. A total of 1,378 participants were tested across 4 study sites. Compared with standard of care RT-PCR testing, the overall sensitivity and specificity of the Atila iAMP test for detection of SARS-CoV-2 were 76.2% and 94.9%, respectively, and increased to 88.8% and 89.5%, respectively, after exclusion of an outlier study site. Sensitivity varied based on the anatomic site from which the sample was collected. Sensitivity for nasopharyngeal sampling was 65.4% (range across study sites, 52.8% to 79.8%), for midturbinate was 88.2%, for saliva was 55.1% (range across study sites, 42.9% to 77.8%), and for anterior nares was 66.7% (range across study sites, 63.6% to 76.5%). The specificity for these anatomic collection sites ranged from 96.7% to 100%. Sensitivity improved in symptomatic patients (overall, 82.7%) and those with a higher viral load (overall, 92.4% for cycle threshold [CT] of #25). Sensitivity and specificity of the OptiGene direct plus RT-LAMP test, which was conducted at a single study site, were 25.5% and 100%, respectively. The Atila iAMP COVID test with midturbinate sampling is a rapid, low-cost assay for detecting SARS-CoV-2, especially in symptomatic patients and those with a high viral load, and could be used to reduce the risk of SARS-CoV-2 transmission in clinical settings. Variation of performance between study sites highlights the need for site-specific clinical validation of these assays before clinical adoption. IMPORTANCE Numerous SARS-CoV-2 detection assays have been developed and introduced into the market under emergency use authorizations (EUAs). EUAs are granted primarily based on small studies of analytic sensitivity and specificity with limited clinical validations. A thorough clinical performance evaluation of SARS-CoV-2 assays is important to understand the strengths, limitations, and specific applications of these assays. In this first large-scale multicentric study, we evaluated the clinical performance and operational characteristics of two isothermal amplification-based SARS-CoV-2 tests, namely, (i) iAMP COVID-19 detection test (Atila BioSystems, USA) and (ii) COVID-19 direct plus RT-LAMP test (OptiGene Ltd., UK), compared with those of clinical RT-PCR tests using different sampling strategies (i.e., nasopharyngeal, self-sampled anterior nares, self-sampled midturbinate, and saliva). An important specific use for these isothermal amplification-based, rapid, low-cost, and easy-to-perform SARS-CoV-2 assays is to allow for a safer return to preventive clinical encounters, such as cancer screening, particularly in low- and middle-income countries that have low SARS-CoV-2 vaccination rates