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Fuel interactions in contracting muscle represent a complex interplay between enzymes regulating carbohydrate and fatty acid catabolism, converging in the mitochondrial matrix. While increasing exercise intensity promotes carbohydrate use at the expense of fatty acid oxidation, the mechanisms under-lying this effect remain poorly elucidated. As a potential explanation, we investigated whether exercise-induced reductions in intramuscular pH (acidosis) attenuate carnitine palmitoyltransferase-I (CPT-I)-supported bioenergetics, the rate-limiting step for fatty acid oxidation within mitochondria. Specifically, we assessed the effect of a physiologically relevant reduction in pH (pH 7.2 versus 6.8) on single and mixed substrate respiratory responses in murine skeletal muscle isolated mitochondria and permeabilized fibers. While pH did not influence oxidative phosphorylation stoichiometry (ADP/O ratios), coupling efficiency, oxygen affinity, or ADP respiratory responses, acidosis impaired lipid bioenergetics by attenuating respiration with L-carnitine and palmitoyl-CoA, while enhancing the inhibitory effect of malonyl-CoA on CPT-I. These acidotic effects were largely retained following a single bout of intense exercise. At rest, pyruvate and succinate-supported respiration were also impaired by acidosis. However, providing more pyruvate and ADP at pH 6.8 to model increases in glycolytic flux and ATP turnover with intense exercise overcame the acidotic attenuation of carbohydrate-linked oxidative phosphorylation. Importantly, this situation is fundamentally different from lipids where CPT-I substrate sensitivity and availability is impaired at higher power outputs suggesting lipid metabolism may be more susceptible to the effects of acidosis, possibly contributing to fuel shifts with increasing exercise intensity. [ABSTRACT FROM AUTHOR]

Abstract: A set of vertices in a graph is a 2-dominating set if every vertex of not in is adjacent to at least two vertices in . The 2-domination number is the minimum cardinality of a 2-dominating set in . The annihilation number is the largest integer such that the sum of the first terms of the nondecreasing degree sequence of is at most the number of edges in . The conjecture-generating computer program, Graffiti.pc, conjectured that holds for every connected graph . It is known that this conjecture is true when the minimum degree is at least 3. The conjecture remains unresolved for minimum degree 1 or 2. In this paper, we prove that the conjecture is indeed true when is a tree, and we characterize the trees that achieve equality in the bound. It is known that if is a tree on vertices with vertices of degree 1, then . As a consequence of our characterization, we also characterize trees that achieve equality in this bound. [Copyright &y& Elsevier]

Abstract: A set S of vertices in a graph G is a total dominating set if every vertex of G is adjacent to some vertex in S. The minimum cardinality of a total dominating set of G is the total domination number of G. A graph is total domination vertex removal stable if the removal of an arbitrary vertex leaves the total domination number unchanged. On the other hand, a graph is total domination vertex removal changing if the removal of an arbitrary vertex changes the total domination number. In this paper, we study total domination vertex removal changing and stable graphs. [Copyright &y& Elsevier]

Abstract: A connected graph is total domination stable upon edge removal, if the removal of an arbitrary edge does not change the total domination number. We determine the minimum number of edges required for a total domination stable graph in terms of its order and total domination number. [Copyright &y& Elsevier]

Abstract: A set of vertices in a graph is a total dominating set of if every vertex of is adjacent to some vertex in . The minimum cardinality of a total dominating set of is the total domination number of . A graph is total domination edge critical if the removal of any arbitrary edge increases the total domination number. On the other hand, a graph is total domination edge stable if the removal of any arbitrary edge has no effect on the total domination number. In this paper, we characterize total domination edge critical graphs. We also investigate various properties of total domination edge stable graphs. [ABSTRACT FROM AUTHOR]

This study set out to examine pre-analytical factors affecting the frequency of positive results in newborn screening for biotinidase deficiency. This investigation was prompted by an increase in the annual screen positive rate for biotinidase deficiency in Ontario from 2.65x10−4 in 2016 to 6.57x10−4 in 2017. Season and trend decomposition was used to separate seasonality from an underlying trend in the time series of biotindase activity measurements for the period 2014–01-12 to 2019–07-27 (n = 798,770). This analysis revealed a marked seasonal effect (winter = median + ⩽ 17 MRU, summer = mean - ⩽ 20 MRU) and a non-linear negative trend. Seasonal temperature was correlated with biotinidase results (Pearson's r = 0.79) but not with the observed negative trend (Pearson's r = 0.0025). Time series analysis of biotinidase results grouped by print lot of filter paper revealed that recently printed filter paper cards inhibit biotinidase and that this inhibition resolved over time. This study demonstrates that biotindase activity is inhibited by both increased seasonal temperature and collection on newly printed filter cards. [ABSTRACT FROM AUTHOR]

Rotavirus vaccines are effective in preventing severe rotavirus. Haiti introduced 2-dose monovalent (G1P[8]) rotavirus vaccine recommended for infants at 6 and 10 weeks of age in 2014. We calculated the effectiveness of rotavirus vaccine against hospitalization for acute gastroenteritis in Haiti. We enrolled children 6–59 months old admitted May 2014-September 2019 for acute watery diarrhea at any sentinel surveillance hospital. Stool was tested for rotavirus using enzyme immunoassay (EIA) and genotyped with multiplex one-step RT-PCR assay and Sanger sequencing for stratification by genotype. We used a case-negative design where cases were children positive for rotavirus and controls were negative for rotavirus. Only children eligible for vaccination were included and a child was considered vaccinated if vaccine was given ≥ 14 days before enrollment. We used unconditional logistic regression to calculate odds ratios and calculated 2-dose and 1-dose vaccine effectiveness (VE) as (1 - odds ratio) * 100. We included 129 (19%) positive cases and 543 (81%) negative controls. Among cases, 77 (60%) were positive for equine-like G3P[8]. Two doses of rotavirus vaccine were 66% (95% CI: 44, 80) effective against hospitalizations due to any strain of rotavirus and 64% (95% CI: 33, 81) effective against hospitalizations due to the equine-like G3P[8] genotype. These findings are comparable to other countries in the Americas region. To the best of our knowledge, this is the first VE estimate both against the equine-like G3P[8] genotype and from a Caribbean country. Overall, these results support rotavirus vaccine use and demonstrate the importance of complete vaccination. [ABSTRACT FROM AUTHOR]

Estimating demographic parameters is key for unraveling the mechanisms governing the population dynamics of species of conservation concern. Endangered green sea turtles navigate vast geographical ranges during their life cycle and face various pressures in coastal areas, especially during their juvenile life-stage. Here, we investigated survival, abundance, recruitment and emigration of juvenile green turtles on two developmental grounds in Martinique, French West Indies, using a capture-mark-recapture dataset of 658 captures over 10 years. We detected increasing abundances of green turtles, likely attributed to the continuous recruitment of new individuals, low mortality and low rate of emigration from these two developmental sites. Local recruitment slightly decreased with small turtle densities while emigration strongly increased with large turtle densities. These results associated with known food availability and size-dependent diet preference of local green turtles suggest that the expansion of invasive seagrass H. stipulacea may facilitate the settlement of small juveniles, however it also limits the capacity of seagrass beds to sustain large juveniles. Boat anchorage, pollution and H. stipulacea invasion reduced the availability of native seagrass species. This could intensify competition between large turtles, trigger earlier emigration, therefore modifying the structure of the green turtle population in Martinique. Measures to protect native seagrass beds are essential to maintain their capacity to sustain the entire green turtle developmental life-stage. This study will help to connect sea turtle life-stages and to inspire efficient regional conservation measures. Finally, our results will help to understand the demography of endangered megaherbivores in context of grazing areas degradation. • Juvenile green turtle survival, abundance, recruitment and emigration were estimated. • Emigration is density-dependent, and recruitment is likely driven by external factors. • Size-dependent diet and H. stipulacea invasion may explain the observed dynamics. • Seagrass protection and restoration is needed to protect juvenile foraging grounds. • Considering perturbation to grazing areas is key for megaherbivore conservation. [ABSTRACT FROM AUTHOR]

Silicon nanomembranes are thin nanoporous films that are frequently used as separation tools for nanoparticles and biological materials. In such applications, increased differential pressure across the nanomembranes directly increases process throughput. Therefore, a predictive tool governing the macroscale failure of the porous thin films is fundamentally important in application areas where high differential pressures are desired. Although the deflections and stresses of the nanomembranes can be reliably predicted, a straightforward and prognostic failure model has yet to be outlined. In this publication, a brittle macroscale failure model is established and validated with experimental results. Theoretical agreement with experiments within 10% accuracy offers reliable failure predictions for square membrane dimensions from 60 μm to 1.5 mm through over 100 trials. The methodology relies on an effective fracture toughness from previously published work that is incorporated through Griffith's law. These developments will be useful in the selection of nanomembranes for particular applications and will help guide the design of materials with improved strength. The model should also prove useful for high-volume, in-line processing and inspection of nanomembranes as their role becomes more prominent in industry. [ABSTRACT FROM AUTHOR]

Oleic acid (OA) is known to bind and change the bioactivities of proteins, such as α-lactalbumin and β-lactoglobulin in vitro . The objective of this study was to determine if OA binds to allergens from a peanut extract or cashew allergen and changes their allergenic properties. Peanut extract or cashew allergen (Ana o 2) was treated with or without 5 mM sodium oleate at 70 °C for 60 min (T1) or under the same conditions with an additional overnight incubation at 37 °C (T2). After treatment, the samples were dialyzed and analyzed by SDS–PAGE and for OA content. IgE binding was evaluated by ELISA and western blot, using a pooled serum or plasma from individuals with peanut or cashew allergies. Results showed that OA at a concentration of 5 mM reduced IgE binding to the allergens. Peanut sample T2 exhibited a lower IgE binding and a higher OA content (protein-bound) than T1. Cashew allergen T2 also showed a reduction in IgE binding. We conclude that OA reduces the allergenic properties of peanut extract and cashew allergen by binding to the allergens. Our findings indicate that OA in the form of sodium oleate may be potentially useful as a coating to reduce the allergenic properties of peanut and cashew allergens. [ABSTRACT FROM AUTHOR]

Abstract: This study examined effects of blending desalinated water with conventionally treated surface water on iron corrosion and release from corroding metal surfaces and pre-existing scales exposed to waters having varying fractions of desalinated water, alkalinities, pH values and orthophosphate levels. The presence of desalinated water resulted in markedly decreased 0.45 μm-filtered soluble iron concentrations. However, higher fractions of desalinated water in the blends were also associated with more fragile corroding surfaces, lower retention of iron oxidation products and release of larger iron particles in the bulk water. SEM, XRD and XANES data showed that in surface water, a dense layer of amorphous ferrihydrite phase predominated in the corrosion products. More crystalline surface phases developed in the presence of desalinated water. These solid phases transformed from goethite to lepidocrocite with increased fraction of desalinated water. These effects are likely to result from a combination of chemical parameters, notably variations of the concentrations of natural organic matter, calcium, chloride and sulfate when desalinated and conventionally treated waters are blended. [Copyright &y& Elsevier]

Abstract: This study examined effects of desalinated water on the corrosion of and metal release from copper and lead-containing materials. A jar test protocol was employed to examine metal release from copper and lead–tin coupons exposed to water chemistries with varying blending ratios of desalinated water, alkalinities, pHs and orthophosphate levels. Increasing fractions of desalinated water in the blends resulted in non-monotonic changes of copper and lead release, with generally lower metal concentrations in the presence of desalinated water, especially when its contribution increased from 80% to 100%. SEM examination showed that the increased fractions of desalinated water were associated with pronounced changes of the morphology of the corrosion scales, likely due to the influence of natural organic matter. This hypothesis was corroborated by the existence of correlations between changes of the ζ-potential of representative minerals (malachite and hydrocerussite) and metal release. For practical applications, maintaining pH at 7.8 and adding 1 mg/L orthophosphate as PO4 were concluded to be adequate to decrease copper and lead release. Lower alkalinity of desalinated water was beneficial for blends containing 50% or more desalinated water. [Copyright &y& Elsevier]

Abstract: In this work, we present for the first time, a highly scalable general high voltage MOSFET model, which can be used for any high voltage MOSFET with extended drift region. This model includes physical effects like the quasi-saturation, impact-ionization and self-heating, and a new general model for drift resistance. The model is validated on the measured characteristics of two widely used high voltage devices in the industry i.e. LDMOS and VDMOS devices, and implemented on commercial circuit simulators like SABER (Synopsys), ELDO (Mentor Graphics), Spectre (Cadence) and UltraSim (Cadence). The accuracy of the model is better than 10% for DC I–V and g–V characteristics and shows good behavior for all capacitances which are unique for these devices showing peaks and shift of peaks with bias variation. The model also exhibits excellent scalability with transistor width, drift length, number of fingers and temperature. [Copyright &y& Elsevier]

Abstract: Researchers at the Royal Military College of Canada have accumulated extensive dose measurements performed at jet altitudes on over 160 flights and with a wide variety of detectors including a tissue equivalent proportional counter (TEPC), a smart wide energy neutron detection instrument (SWENDI), bubble detectors, thermoluminescent detectors (TLD) and an ion chamber. The summation of the individual low and high LET results from the latter equipment compared successfully to those from the TEPC on each flight. The data from these numerous worldwide flights have been encapsulated into a program that calculates the radiation dose for any flight in the world at any period in the solar cycle. This experimentally based program, Predictive Code for AIRcrew Exposure (PCAIRE) has been designed to be used by the airline industry to meet national dosimetry requirements. In Canada, for example, such a code can be used, supported by periodic measurements. With this latter requirement in mind and a desire to decrease equipment size, the silicon-based LIULIN-4N LET (linear energy transfer) spectrometer has been assessed to determine its suitability as a mixed field instrument and possible code verification tool. Data obtained from the LIULIN and TEPC in ground-based experiments at the CERN-EC Reference-field Facility (CERF) and on 42 jet-altitude flights have been compared. Analysis of these data has resulted in two different mathematical correlations which can be used to determine the ambient dose equivalent, H ∗(10), from the LIULIN absorbed dose output. With either calibration factor, the LIULIN instrument could now be used as a simple, compact and portable detector for routine monitoring. [Copyright &y& Elsevier]