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Ground ice maps at small scales offer generalized depictions of abundance across broad circumpolar regions. In this paper, the effect of surficial geology mapping scale on modelled ground ice abundance is examined in the Slave Geological Province of the Canadian Shield, a region where the geological and glacial legacy has produced a landscape with significant variation in surface cover. Existing model routines from the Ground ice map of Canada (GIMC) were used with a 1:125 000-scale regional surficial geology compilation and compared to the national outputs, which are based on surficial geology at a 1:5 000 000 scale. Overall, the regional-scale modelling predicts much more ground ice than the GIMC due to greater representation of unconsolidated sediments in the region. Improved modelling accuracy is indicated by comparison of the outputs to empirical datasets due to improved representation of the inherent regional heterogeneity in surficial geology. The results demonstrate that the GIMC significantly underestimates the abundance and distribution of ground ice over Canadian Shield terrain. In areas with limited information on ground ice, regional-scale modelling may provide useful reconnaissance-level information to help guide the field-based investigations required for planning infrastructure development. The use of current small-scale ground ice mapping in risk or cost assessments related to permafrost thaw may significantly influence the accuracy of outputs in areas like the Canadian Shield, where surficial materials range from bedrock to frost-susceptible deposits over relatively short distances.

Objectives This research aims to identify genes which are dysregulated in premalignant cells during the development of Adult T-cell Leukaemia/lymphoma (ATL). Monoclonal expansion of HTLV-1infected T cells is observed in > 90% of ATL patients. Our group has previously shown that premalignant 'ATL-like' clones circulate in the blood of HTLV-1 carriers before the development of ATL. In this study, we aimed to identify intracorrelated gene networks which are associated with ATL-like monoclonal expansion, by comparing gene expression of ATL-like clonal with polyclonal HTLV-1 infected and uninfected T cells from within the same individuals. Methods Peripheral blood mononuclear cells (PBMCs) from 17 HTLV-1-infected individuals, who had not been diagnosed with ATL at the time of sample collection, were flow-sorted based on cell surface markers associated with HTLV-1 infection (CD4+CCR4+CD26-) and clonal expansion (T cell receptor Vbeta subunits) to obtain ATL-like clones (n = 9), polyclonal HTLV-1-infected T cells (n = 17), and uninfected T cells (n = 16). RNA was extracted and subjected to RNA-Seq. Here we analysed the RNA-Seq data using a weighted gene co-expression network analysis (WGCNA) program, followed by multiple, complementary gene annotation tools (CytoHubba, DAVID, and GSEA) to identify important networks as well as specific hub genes. Results WGCNA analysis identified 40 modules of correlated genes, two of which showed strong correlations with clonality and infection respectively. GO terms enriched from each module are associated with 'infection' and 'immune response'. The top 30 hub genes, which are the most intra-connected within each module, were identified and ranked using 12 different topological calculations using CytoHubba. Conclusion This research identified the important hub genes which are strongly correlated with HTLV-1 infection and clonal expansion, to be further explored as potential mechanisms for oligoclonal expansion or as biomarkers and/or therapeutic targets. [ABSTRACT FROM AUTHOR]

Ground ice melt caused by climate-induced permafrost degradation may trigger significant ecological change, damage infrastructure, and alter biogeochemical cycles. The fundamental ground ice mapping for Canada is now >20 years old and does not include significant new insights gained from recent field- and remote-sensing-based studies. New modelling incorporating paleogeography is presented in this paper to depict the distribution of three ground ice types (relict ice, segregated ice, and wedge ice) in northern Canada. The modelling uses an expert-system approach in a geographic information system (GIS), founded in conceptual principles gained from empirically based research, to predict ground ice abundance in near-surface permafrost. Datasets of surficial geology, deglaciation, paleovegetation, glacial lake and marine limits, and modern permafrost distribution allow representations in the models of paleoclimatic shifts, tree line migration, marine and glacial lake inundation, and terrestrial emergence, and their effect on ground ice abundance. The model outputs are generally consistent with field observations, indicating abundant relict ice in the western Arctic, where it has remained preserved since deglaciation in thick glacigenic sediments in continuous permafrost. Segregated ice is widely distributed in fine-grained deposits, occurring in the highest abundance in glacial lake and marine sediments. The modelled abundance of wedge ice largely reflects the exposure time of terrain to low air temperatures in tundra environments following deglaciation or marine/glacial lake inundation and is thus highest in the western Arctic. Holocene environmental changes result in reduced ice abundance where the tree line advanced during warmer periods. Published observations of thaw slumps and massive ice exposures, segregated ice and associated landforms, and ice wedges allow a favourable preliminary assessment of the models, and the results are generally comparable with the previous ground ice mapping for Canada. However, the model outputs are more spatially explicit and better reflect observed ground ice conditions in many regions. Synthetic modelling products that incorporated the previous ground ice information may therefore include inaccuracies. The presented modelling approach is a significant advance in permafrost mapping, but additional field observations and volumetric ice estimates from more areas in Canada are required to improve calibration and validation of small-scale ground ice modelling. The ground ice maps from this paper are available in the supplement in GeoTIFF format.

The purpose of this study was to investigate the precision of CT-based volumetric measurements of artificial small pulmonary nodules under ex vivo conditions. We implanted 322 artificial nodules in 23 inflated ex vivo porcine lungs in a dedicated chest phantom. The lungs were examined with a multislice spiral CT (20 mAs, collimation 16x0.75 mm, 1 mm slice thickness, 0.7 mm increment). A commercial volumetry software package (LungCARE VA70C-W; Siemens, Erlangen, Germany) was used for volume analysis in a semi-automatic and a manual corrected mode. After imaging, the lungs were dissected to harvest the nodules for gold standard determination. The volumes of 202 solitary, solid and well-defined lesions without contact with the pleura, greater bronchi or vessels were compared with the results of volumetry. A mean nodule diameter of 8.3 mm (+/-2.1 mm) was achieved. The mean relative deviation from the true lesion volume was -9.2% (+/-10.6%) for semi-automatic and -0.3% (+/-6.5%) for manual corrected volumetry. The subgroup of lesions from 5 mm to <10 mm in diameter showed a mean relative deviation of -8.7% (+/-10.9%) for semi-automatic volumetry and -0.3% (+/-6.9%) for manually corrected volumetry. We conclude that the presented software allowed for precise volumetry of artificial nodules in ex vivo lung tissue. This result is comparable to the findings of previous in vitro studies. [ABSTRACT FROM AUTHOR]

Spatially detailed information on permafrost distribution and change with climate is important for land use planning, infrastructure development, and environmental assessments. However, the required soil and surficial geology maps in the North are coarse, and projected climate scenarios vary widely. Considering these uncertainties, we propose a new approach to mapping permafrost distribution and change by integrating remote sensing data, field measurements, and a process-based model. Land cover types from satellite imagery are used to capture the general land conditions and to improve the resolution of existing permafrost maps. For each land cover type, field observations are used to estimate the probabilities of different ground conditions. A process-based model is used to quantify the evolution of permafrost for each ground condition under three representative climate scenarios (low, medium, and high warming). From the model results, the probability of permafrost occurrence and the most likely permafrost conditions are determined. We apply this approach at 20 m resolution to a large area in Northwest Territories, Canada. Mapped permafrost conditions are in agreement with field observations and other studies. The data requirements, model robustness, and computation time are reasonable, and this approach may serve as a practical means to mapping permafrost and changes at high resolution in other regions.

In warm and humid regions, the productivity of sorghum is significantly limited by the fungal hemibiotrophic pathogen Colletotrichum sublineola, the causal agent of anthracnose, a problematic disease of sorghum (Sorghum bicolor (L.) Moench) that can result in grain and biomass yield losses of up to 50%. Despite available genomic resources of both the host and fungal pathogen, the molecular basis of sorghum−C. sublineola interactions are poorly understood. By employing a dual-RNA sequencing approach, the molecular crosstalk between sorghum and C. sublineola can be elucidated. In this study, we examined the transcriptomes of four resistant sorghum accessions from the sorghum association panel (SAP) at varying time points post-infection with C. sublineola. Approximately 0.3% and 93% of the reads mapped to the genomes of C. sublineola and Sorghum bicolor, respectively. Expression profiling of in vitro versus in planta C. sublineola at 1-, 3-, and 5-days post-infection (dpi) indicated that genes encoding secreted candidate effectors, carbohydrate-active enzymes (CAZymes), and membrane transporters increased in expression during the transition from the biotrophic to the necrotrophic phase (3 dpi). The hallmark of the pathogen-associated molecular pattern (PAMP)-triggered immunity in sorghum includes the production of reactive oxygen species (ROS) and phytoalexins. The majority of effector candidates secreted by C. sublineola were predicted to be localized in the host apoplast, where they could interfere with the PAMP-triggered immunity response, specifically in the host ROS signaling pathway. The genes encoding critical molecular factors influencing pathogenicity identified in this study are a useful resource for subsequent genetic experiments aimed at validating their contributions to pathogen virulence. This comprehensive study not only provides a better understanding of the biology of C. sublineola but also supports the long-term goal of developing resistant sorghum cultivars.

Abstract The present study examined heat stress vulnerability of apparently healthy older vs. young adults and characterized critical environmental limits for older adults in an indoor setting at rest (Rest) and during minimal activity associated with activities of daily living. Critical environmental limits are combinations of ambient temperature and humidity above which heat balance cannot be maintained (i.e., becomes uncompensable) for a given metabolic heat production. Here we exposed fifty-one young (23 ± 4 yrs) and 49 older (71 ± 6 yrs) adults to progressive heat stress across a wide range of environments in an environmental chamber during Minimal Activity (young and older subjects) and Rest (older adults only). Heat compensability curves were shifted leftward for older adults indicating age-dependent heat vulnerablity (p

No abstract available.

We investigate the differences in the dynamics of the ultrafast photo-induced metal–insulator transition (MIT) of two VO2 thin films deposited on different substrates, TiO2 and Al2O3, and in particular the temperature dependence of the threshold laser fluence values required to induce various MIT stages in a wide range of sample temperatures 150–320 K. We identified that, although the general pattern of MIT evolution was similar for the two samples, there were several differences. Most notably, the threshold values of laser fluence required to reach the transition to a fully metallic phase in the VO2 film on the TiO2 substrate were nearly constant in the range of temperatures considered, whereas the VO2/Al2O3 sample showed clear temperature dependence. Our analysis qualitatively connects such behavior to the structural differences in the two VO2 films. [ABSTRACT FROM AUTHOR]

Abstract The expressed goal of limiting workplace heat stress exposures to a core temperature (Tc) of 38°C traces back to a 1969 World Health Organization Technical Report (WHO Series 412). The actual goal was to limit exposures to the upper limit of the prescriptive zone (ULPZ). To explore the physiological strain at the ULPZ, progressive heat stress protocol data from Penn State University (PSU) and University of South Florida (USF) below and at the ULPZ were used to articulate the relation of Tc and heart rate (HR) to metabolic rate (MR) with consideration of acclimatization state, clothing, exposure condition (PreULPZ vs. ULPZ), and sex. Regression models demonstrated the association of MR and sex with Tc and HR. At the ULPZ, women had systematically higher values of Tc and HR than men at the same MR likely due to higher relative demands. There was no effect for acclimatization state and clothing. As expected for individuals, Tc was practically constant below the ULPZ and HR exhibited increasing values approaching the ULPZ. At 490 W, the high MR cited in the WHO document, the mean Tc for men was near the 38°C limit with systematically lower Tc at lower MRs.

The traditional approach to harnessing the impurity-photovoltaic effect to improve solar cell performance is plagued by additional recombination caused by the impurity centres. This extra recombination channel is usually deemed to outweigh the benefits of additional generation of electron-hole pairs via sub-band-gap absorption through the impurity levels. Here we consider an alternative approach that restricts the impurity levels to a film with a wider band gap at the rear of a solar cell, isolating the impurities from the minority carriers generated in the base, but, in principle, still allowing impurity-generated carriers to contribute to the cell current. Initial proof-of-concept experiments show that implantation of silicon ions into amorphous silicon films on the rear of crystalline silicon wafers results in the desired increase in sub-band-gap absorptance of infrared photons, without degrading the surface passivation properties of the amorphous layer. However, these defect states are not thermally stable, and in any case do not result in additional carriers being injected into the silicon wafer itself, either because the infrared-generated carriers relax back to the valence band before the second photon can be absorbed, or because the free carriers recombine before reaching the wafer interface. Subsequent attempts involving implantation of iron and erbium impurities to generate stable absorption centres in the amorphous silicon films also failed to inject additional carriers into the crystalline wafer. Possible modifications that may alleviate these problems are discussed. [ABSTRACT FROM AUTHOR]

Abstract We tested the hypothesis that post‐COVID‐19 adults (PC) would have impaired cutaneous nitric oxide (NO)‐mediated vasodilation compared to controls (CON). We performed a cross‐sectional study including 10 (10 F/0 M, 69 ± 7 years) CON and 7 (2 F/5 M, 66 ± 8 years) PC (223 ± 154 days post‐diagnosis). COVID‐19 symptoms severity (survey) was assessed (0–100 scale for 18 common symptoms). NO‐dependent cutaneous vasodilation was induced by a standardized 42°C local heating protocol and quantified via perfusion of 15 mM NG‐nitro‐L‐arginine methyl ester during the plateau of the heating response (intradermal microdialysis). Red blood cell flux was measured with laser‐Doppler flowmetry. Cutaneous vascular conductance (CVC = flux/mm Hg) was presented as a percentage of maximum (28 mM sodium nitroprusside +43°C). All data are means ± SD. The local heating plateau (CON: 71 ± 23% CVCmax vs. PC: 81 ± 16% CVCmax, p = 0.77) and NO‐dependent vasodilation (CON: 56 ± 23% vs. PC: 60 ± 22%, p = 0.77) were not different between groups. In the PC group neither time since diagnosis nor peak symptom severity (46 ± 18 AU) correlated with NO‐dependent vasodilation (r

Введение. В настоящее время, несмотря на благоприятный в целом патоморфоз туберкулёза (ТБ), сохраняется ряд факторов, оказывающих негативное влияние на эпидемиологическую ситуацию, клинические проявления и результаты лечения. Цель. Определить роль отягощающих факторов в развитии деструктивного туберкулёза лёгких. Материал и методы. Проведено проспективное когортное исследование. Обследованы пациенты, поступившие в стационар Гродненского областного клинического центра «Фтизиатрия», а также в Республиканскую туберкулёзную больницу «Новоельня». В зависимости от превалирующего отягощающего фактора пациенты были разделены на 10 групп. Кроме того, сформированы еще 2 группы пациентов с наличием широкой лекарственной устойчивости микобактрий туберкулёза (ШЛУ МБТ). Полученные результаты свидетельствуют о существенном негативном влиянии отягощающих факторов на формирование деструктивных процессов в лёгких. Более значимыми по данному фактору следует считать пациентов с ТБ, сопровождающимся сахарным диабетом (СД), синдромом зависимости от алкоголя (СЗА), хронические неспецифические заболевания органов дыхания (ХНЗОД), прибывших из исправительно-трудовых учреждений (ИТУ) и с наличием нескольких факторов одновременно. Результаты. Анализ полученных результатов свидетельствует о том, что во всех когортах пациентов частота наличия полостей распада превышает таковую у пациентов с туберкулёзом лёгких без наличия значимых факторов риска. Выводы. Полученные результаты свидетельствуют о наличии зависимости частоты формирования деструктивных форм туберкулёза при МЛУ ТБ от ряда отягощающих факторов. Наиболее значимые в этом отношении – СД, несколько факторов одновременно, СЗА, пребывание в ИТУ, ХНЗОД. Такие факторы, как контакт, заболевания желудочно-кишечного тракта, существенного влияния на формирование деструкции в лёгких при МЛУ ТБ не оказывают. При наличии ШЛУ-ТБ отмечается наиболее высокая частота деструктивных форм (свыше 70%), достигающая 76,0% у пациентов со ШЛУ-ТБ в сочетании с СЗА.

Surgical site infection risk continues to increase due to lack of efficacy in current standard of care drugs. New methods to treat or prevent antibiotic-resistant bacterial infections are needed. Multivalent Adhesion Molecules (MAM) are bacterial adhesins required for virulence. We developed a bacterial adhesion inhibitor using recombinant MAM fragment bound to polymer scaffold, mimicking MAM7 display on the bacterial surface. Here, we test MAM7 inhibitor efficacy to prevent Gram-positive and Gram-negative infections. Using a rodent model of surgical infection, incision sites were infected with antibiotic-resistant bioluminescent strains of Staphylococcus aureus or Pseudomonas aeruginosa. Infections were treated with MAM7 inhibitor or control suspension. Bacterial abundance was quantified for nine days post infection. Inflammatory responses and histology were characterized using fixed tissue sections. MAM7 inhibitor treatment decreased burden of S. aureus and P. aeruginosa below detection threshold. Bacterial load of groups treated with control were significantly higher than MAM7 inhibitor-treated groups. Treatment with inhibitor reduced colonization of clinically-relevant pathogens in an in vivo model of surgical infection. Use of MAM7 inhibitor to block initial adhesion of bacteria to tissue in surgical incisions may reduce infection rates, presenting a strategy to mitigate overuse of antibiotics to prevent surgical site infections.

Dehydration ≥2% loss of body mass is associated with reductions in performance capacity, and carbohydrate (CHO)-electrolyte solutions (CES) are often recommended to prevent dehydration and provide a source of exogenous carbohydrate during exercise. It is also well established that performance capacity in the heat is diminished compared to cooler conditions, a response attributable to greater cardiovascular strain caused by high skin and core temperatures. Because hydration status, environmental conditions, and carbohydrate availability interact to influence performance capacity, we sought to determine how these factors affect push-to-the-finish cycling performance. Ten young trained cyclists exercised at a moderate intensity (2.5 W·kg−1) in a hot-dry condition [40°C, 20% relative humidity (RH)] until dehydration of ~2% body mass. Subjects then consumed either no fluid (NF) or enough fluid (water, WAT; Gatorade®, GAT; or GoodSport™, GS) to replace 75% of lost body mass over 30 min. After a 30-min light-intensity warm-up (1.5 W·kg−1) in a 35°C, 20% RH environment, subjects then completed a 120-kJ time trial (TT). TT time-to-completion, absolute power, and relative power were significantly improved in WAT (535 ± 214 s, 259 ± 99 W, 3.3 ± 0.9 W·kg−1), GAT (539 ± 226 s, 260 ± 110 W, 3.3 ± 1.0 W·kg−1), and GS (534 ± 238 s, 262 ± 105 W, 3.4 ± 1.0 W·kg−1) compared to NF (631 ± 310 s, 229 ± 96 W, 3.0 ± 0.9 W·kg−1) all (p < 0.01) with no differences between WAT, GAT, and GS, suggesting that hydration is more important than carbohydrate availability during exercise in the heat. A subset of four subjects returned to the laboratory to repeat the WAT, GAT, and GS treatments to determine if between-beverage differences in time-trial performance were evident with a longer TT in thermoneutral conditions. Following dehydration, the ambient conditions in the environmental chamber were reduced to 21°C and 20% RH and subjects completed a 250-kJ TT. All four subjects improved TT performance in the GS trial (919 ± 353 s, 300 ± 100 W, 3.61 ± 0.86 W·kg−1) compared to WAT (960 ± 376 s, 283 ± 91 W, 3.43 ± 0.83 W·kg−1), while three subjects improved TT performance in the GAT trial (946 ± 365 s, 293 ± 103 W, 3.60 ± 0.97 W·kg−1) compared to WAT, highlighting the importance of carbohydrate availability in cooler conditions as the length of a push-to-the-finish cycling task increases.

Animal behaviorists have made extensive use of GPS technology since 1991. In contrast, psychological research has made little use of the technology, even though the technology is relatively inexpensive, familiar, and widespread. Hence, its potential for pure and applied psychological research remains untapped. We describe three methods psychologists could apply to individual differences research, clinical research, or spatial use research. In the context of individual differences research, GPS technology permits us to test hypotheses predicting specific relations among patterns of spatial use and individual differences variables. In a clinical context, GPS technology provides outcome measures that may relate to the outcome of interventions designed to treat psychological disorders that, for example, may leave a person homebound (e.g. Agoraphobia, PTSD, TBI). Finally, GPS technology provides natural measures of spatial use. We, for example, used GPS technology to quantify traffic flow and exhibit use at the Arizona Sonora Desert Museum. Interested parties could easily extend this methodology some aspects of urban planning or business usage. DOI:10.2458/azu_jmmss_v1i1_wolf