Elimination of A-234 from the environment: Effect of different decontaminants.

With the fact that there are Novichoks in the list of toxic chemicals by the Chemical Weapons Convention parties, it is necessary to develop methods of effective neutralization of the agents as well as for other organophosphorus toxic substances. However, experimental studies on their persistence in the environment and effective decontamination measures remain scarce. Therefore, here, we investigated the persistence behavior and decontamination methods of A-234 (ethyl N-[1-(diethylamino)ethylidene]phosphoramidofluoridate), a Novichok series, A-type nerve agent to assess its potential risk to the environment. Different analytical methods were implemented, including 31P solid-state magic angle spinning nuclear magnetic resonance (NMR), liquid 31P NMR, gas chromatography-mass spectrometry (GC-MS), liquid chromatography-mass spectrometry, and vapor-emission screening using a microchamber/thermal extractor with GC-MS. Our results showed that A-234 is extremely stable in sand and poses a long-lasting risk to the environment even when released in trace quantities. Moreover, the agent is not easily decomposed by water, dichloroisocyanuric acid sodium salt, sodium persulfate, and chlorine-based water-soluble decontaminants. However, it is efficiently decontaminated by Oxone® monopersulfate, calcium hypochlorite, KOH, NaOH, and HCl within 30 min. Our findings provide valuable insights for eliminating the highly dangerous Novichok agents from the environment.

(3 + 2) Cycloaddition Reaction of the Endocyclic N-Silyl Enamine and N,N'-Cyclic Azomethine Imine.

We describe the (3 + 2) cycloaddition reaction of endocyclic N-silyl enamines and N,N'-cyclic azomethine imines. This process utilized the versatile endocyclic N-silyl enamine intermediates from the dearomative hydrosilylation of N-heteroarenes. The resulting tetracyclic pyrazolidinone structure was synthesized by a straightforward and atom-economical process. We also discussed the plausible origins of the different reactivity and endo/exo selectivity in terms of the structures of each proposed transition state. The successful gram-scale synthesis demonstrated the synthetic utility.

Recovered Energy from Salinity Gradients Utilizing Various Poly(Acrylic Acid)-Based Hydrogels.

Hydrogels can be utilized to extract energy from salinity gradients when river water mixes with seawater. Saline-sensitive hydrogels exhibit a reversible swelling/shrinking process when they are, alternately, exposed to fresh and saline water. We present a comparison of several poly(acrylic acid)-based hydrogels, including poly(acrylic acid) (PAA), poly(acrylic acid-co-vinylsulfonic acid) (PAA/PVSA), and poly(4-styrenessulfonic acid-co-maleic acid) interpenetrated in a poly(acrylic acid) network (PAA/PSSA-MA). The hydrogels were synthesized by free radical polymerization, copolymerization, and by semi-IPN (interpenetrating polymer network). The hydrogels were placed in a piston-like system to measure the recovered energy. Semi-IPN hydrogels exhibit a much higher recovered energy compared to the copolymer and PAA hydrogel. The recovered energy of 60 g swollen gel was up to 4 J for the PAA/PSSA-MA hydrogel. The obtained energy per gram dried gel was up to 13.3 J/g. The swelling volume of the hydrogels was maintained for 30 cycles without decline in recovered energy.

Rapid Adoption of Telehealth at an Interprofessional Student-Run Free Clinic.

INTRODUCTION: Student-run free clinics (SRFCs) have become important primary care homes during the COVID-19 pandemic. With students pulled from clinical sites, funding deficits, SRFCs' voluntary nature, and no best practices for telehealth SRFCs, many have been forced to close. This report shares a systematic approach for implementing a telehealth clinic along with initial outcomes from the Dedicated to Aurora's Wellness and Needs (DAWN) SRFC. METHODS: We utilized pilots with students, community volunteers, and patients to identify a telehealth platform. We implemented weekly plan-do-study-act (PDSA) cycles to develop a feasible interprofessional telehealth model. Key PDSA cycle goals included seamless utilization of platform, identification of necessary team members, appropriate scheduling of patients and volunteers, integration of interprofessional learners, positive patient and volunteer experience, and process for identifying and addressing patient social needs. Measured outcomes included total visits, no-show rates, and chief complaints addressed. RESULTS: Outcomes from PDSA cycles included a resultant telehealth clinic team and model, workflow for outreach for social needs screening and navigation, and team training guides. Visit data and no-show rates from January 2020 through July 2020 demonstrated total visits returned to 60% of pre-COVID numbers while no-show rates decreased significantly below pre-COVID rates. A range of acute and chronic concerns were successfully managed via telehealth. CONCLUSION: SRFCs are poised to continue serving an important role in caring for the country's most vulnerable populations. The DAWN telehealth implementation process, outcomes, and resultant protocols may help inform other SRFCs seeking to establish telehealth services.

Synthesis of Cyclic Amidines from Quinolines by a Borane-Catalyzed Dearomatization Strategy.

Described herein is the development of a new synthetic route to cyclic amidines from quinolines. The borane-catalyzed 1,4-hydrosilylation of quinoline was utilized for the dearomatization of the quinolines. The dearomatized enamine intermediate was subsequently reacted with a broad range of organic azides to produce the corresponding cyclic amidines (3,4-dihydroquinolinimines) via a [3 + 2] cycloaddition pathway. Preliminary mechanistic studies suggested that the hydride shift was involved during the cycloaddition.

Salinity Gradient Energy from Expansion and Contraction of Poly(allylamine hydrochloride) Hydrogels.

Salinity gradients exhibit a great potential for production of renewable energy. Several techniques such as pressure-retarded osmosis and reverse electrodialysis have been employed to extract this energy. Unfortunately, these techniques are restricted by the high costs of membranes and problems with membrane fouling. However, the expansion and contraction of hydrogels can be a new and cheaper way to harvest energy from salinity gradients since the hydrogels swell in freshwater and shrink in saltwater. We have examined the effect of cross-linker concentration and different external loads on the energy recovered for this type of energy-producing systems. Poly(allylamine hydrochloride) hydrogels were cross-linked with glutaraldehyde to produce hydrogels with excellent expansion and contraction properties. Increasing the cross-linker concentration markedly improved the energy that could be recovered from the hydrogels, especially at high external loads. A swollen hydrogel of 60 g could recover more than 1800 mJ when utilizing a high cross-linker concentration, and the maximum amount of energy produced per gram of polymer was 3.4 J/g. Although more energy is recovered at high cross-linking densities, the maximum amount of energy produced per gram of polymer is highest at an intermediate cross-linking concentration. Energy recovery was reduced when the salt concentration was increased for the low-concentration saline solution. The results illustrate that hydrogels are promising for salinity gradient energy recovery, and that optimizing the systems significantly increases the amount of energy that can be recovered.

Characteristics of Cu2O:Na Thin Films Prepared by DC Magnetron Sputtering Method at Low Temperature.

In this work, the success of doping Na into Cu2O thin films by reactive DC magnetron sputtering method at low temperature is described for the first time. The characteristics of crystal structure, morphology, optical, electrical properties and binding of elements in Cu2O:Na thin films are carefully investigated. The Cu2O:Na thin films have exhibited high electronic conductivity as p-type semiconductor and absorption in visible range. The highest hole concentration on the order of 1018 cm-3 and the lowest resistivity of 6.726 Ω · cm according to 6.56% Na impurities in Cu2O:Na lattice are also detected. The role of Na impurity in Cu2O structure is proposed that based on the changing of structure and alignment of elements.

Rheological and thermal properties of suspensions of microcapsules containing phase change materials.

The thermal and rheological properties of suspensions of microencapsulated phase change materials (MPCM) in glycerol were investigated. When the microcapsule concentration is raised, the heat storage capacity of the suspensions becomes higher and a slight decline in the thermal conductivity of the suspensions is observed. The temperature-dependent shear-thinning behaviour of the suspensions was found to be strongly affected by non-encapsulated phase change materials (PCM). Accordingly, the rheological properties of the MPCM suspensions could be described by the Cross model below the PCM melting point while a power law model best described the data above the PCM melting point. The MPCM suspensions are interesting for energy storage and heat transfer applications. However, the non-encapsulated PCM contributes to the agglomeration of the microcapsules, which can lead to higher pumping consumption and clogging of piping systems.

Control of ZnO Nanorod Defects to Enhance Carrier Transportation in p-Cu2O/i-ZnO Nanorods/n-IGZO Heterojunction.

The p-Cu2O/i-ZnO nanorods/n-IGZO heterojunctions were fabricated by electrochemical and sputtering method. ZnO nanorods were grown on conductive indium gallium zinc oxide (IGZO) thin film and then p-Cu2O layer was deposited on ZnO nanorods to form the heterojunction. ZnO nanorods play an important role in carrier transport mechanisms and performance of the junction. The changing of defects in ZnO nanorods by annealing samples in air and vacuum have studied. The XRD, photoluminescence (PL) spectroscopy, and FTIR were used to study about structure, and defects in ZnO nanorods. The SEM, i­V characteristics methods were also used to define structure, electrical properties of the heterojunctions layers. The results show that the defects in ZnO nanorods affected remarkably on performance of heterojunctions of solar cells.

Changing the thickness of two layers: i-ZnO nanorods, p-Cu2O and its influence on the carriers transport mechanism of the p-Cu2O/i-ZnO nanorods/n-IGZO heterojunction.

In this study, two layers: i-ZnO nanorods and p-Cu2O were fabricated by electrochemical deposition. The fabricating process was the initial formation of ZnO nanorods layer on the n-IGZO thin film which was prepared by sputtering method, then a p-Cu2O layer was deposited on top of rods to form the p-Cu2O/i-ZnO nanorods/n-ZnO heterojunction. The XRD, SEM, UV-VIS, I-V characteristics methods were used to define structure, optical and electrical properties of these heterojunction layers. The fabricating conditions and thickness of the Cu2O layers significantly affected to the formation, microstructure, electrical and optical properties of the junction. The length of i-ZnO nanorods layer in the structure of the heterojunction has strongly affected to the carriers transport mechanism and performance of this heterojunction.

A Chemical Heat Pack-Based Method For Consistent Heating of Intravenous Fluids.

BACKGROUND: Transfusion of cold intravenous fluids (IVF) can exacerbate hypothermia. Civilian and military guidelines recommend heated IVF for hypothermic patients; however, there is currently no ideal IVF heating system for use in resource-limited settings. OBJECTIVE: Development of a system that uses flameless ration heaters (FRH) and an insulated sleeve for the consistent delivery of IVF at physiologically appropriate temperatures (40°-42°C) over the range of ambient conditions typical of the prehospital and wilderness environments. METHODS: The temperatures of 0.9% normal saline (NS) 1-L bags were measured under 3 ambient conditions: 3°C, 10°C, and 20°C. The IVF was placed in an insulated pouch along with a predetermined number of activated FRH (5 FRH for 3°C, 4 FRH for 10°C, and 3 FRH for 20°C) for 10 minutes before removing the FRHs. The insulated IVF bag was drained through 280 cm of intravenous tubing at a flow rate of 77 mL/min. Raw temperature data for internal and delivery temperatures were collected and analyzed. RESULTS: The temperature of the IVF throughout the delivery of 1 L of NS under the 3 ambient conditions was as follows (mean ± SD): at 3°C ambient, 47° ± 2.1°C internal and 42.6°C ± 1.4°C at delivery; at 10°C ambient, 52.3° ± 2.7°C and 45.2° ± 1.6°C; and at 20°C ambient, 45.5° ± 1°C and 39.7° ± 0.7°C. CONCLUSIONS: The IVF heating system described here reliably delivered physiologically appropriate temperature intravenous fluids in 2 of the 3 ambient treatment conditions. With the appropriate number of FRH for the ambient conditions, this system enables the delivery of warmed IVF to provide active warming, which may be clinically beneficial in the prevention and treatment of hypothermia.

Novel application of chemical cold packs for treatment of exercise-induced hyperthermia: a randomized controlled trial.

OBJECTIVE: Heat-related illness is a common disease with significant morbidity and mortality. Despite no proven efficacy, application of chemical cold packs (CCP) to the skin overlying the large vessels of the neck, groin, and axillae is a traditional recommended cooling modality. The study objective was to compare the cooling rates of CCP applied to these traditional areas vs the glabrous skin surfaces of the cheeks, palms, and soles in exercise-induced hyperthermia. METHODS: Ten healthy adult male volunteers walked on a treadmill in a heated room (40°±0.5°C) while wearing insulated military overgarments until their esophageal temperatures (Tes) reached 39.2°C. Each participant had three heat stress trials on separate days: no treatment followed by randomly ordered traditional (neck, groin, and axillae) cooling and glabrous skin cooling. RESULTS: With no treatment, Tes remained stable after the first 5 minutes of the heat trial (ΔTes=0.12°±0.07°C/10 min). Traditional cooling followed a linear decline (ΔTes=0.17°±0.04°C/10 min; P<.001). Glabrous cooling enhanced the treatment effect by a steeper decline (ΔTes=0.30°±0.06°C/10 min; P<.001), significantly different from traditional cooling by 2-way analysis of variance (P<.001). CONCLUSIONS: Application of CCP to glabrous skin surfaces was more effective for treating exercise-induced heat stress than the traditional CCP cooling intervention. This novel cooling technique may be beneficial as an adjunctive treatment for heat-related illness in the prehospital environment.

Work volume and strength training responses to resistive exercise improve with periodic heat extraction from the palm.

Body core cooling via the palm of a hand increases work volume during resistive exercise. We asked: (a) "Is there a correlation between elevated core temperatures and fatigue onset during resistive exercise?" and (b) "Does palm cooling between sets of resistive exercise affect strength and work volume training responses?" Core temperature was manipulated by 30-45 minutes of fixed load and duration treadmill exercise in the heat with or without palm cooling. Work volume was then assessed by 4 sets of fixed load bench press exercises. Core temperatures were reduced and work volumes increased after palm cooling (Control: Tes = 39.0 ± 0.1° C, 36 ± 7 reps vs. Cooling: Tes = 38.4 ± 0.2° C, 42 ± 7 reps, mean ± SD, n = 8, p < 0.001). In separate experiments, the impact of palm cooling on work volume and strength training responses were assessed. The participants completed biweekly bench press or pull-up exercises for multiple successive weeks. Palm cooling was applied for 3 minutes between sets of exercise. Over 3 weeks of bench press training, palm cooling increased work volume by 40% (vs. 13% with no treatment; n = 8, p < 0.05). Over 6 weeks of pull-up training, palm cooling increased work volume by 144% in pull-up experienced subjects (vs. 5% over 2 weeks with no treatment; n = 7, p < 0.001) and by 80% in pull-up naïve subjects (vs. 20% with no treatment; n = 11, p < 0.01). Strength (1 repetition maximum) increased 22% over 10 weeks of pyramid bench press training (4 weeks with no treatment followed by 6 weeks with palm cooling; n = 10, p < 0.001). These results verify previous observations about the effects of palm cooling on work volume, demonstrate a link between core temperature and fatigue onset during resistive exercise, and suggest a novel means for improving strength and work volume training responses.

Acute light exposure suppresses circadian rhythms in clock gene expression.

Light can induce arrhythmia in circadian systems by several weeks of constant light or by a brief light stimulus given at the transition point of the phase response curve. In the present study, a novel light treatment consisting of phase advance and phase delay photic stimuli given on 2 successive nights was used to induce circadian arrhythmia in the Siberian hamster ( Phodopus sungorus). We therefore investigated whether loss of rhythms in behavior was due to arrhythmia within the suprachiasmatic nucleus (SCN). SCN tissue samples were obtained at 6 time points across 24 h in constant darkness from entrained and arrhythmic hamsters, and per1, per2 , bmal1, and cry1 mRNA were measured by quantitative RT-PCR. The light treatment eliminated circadian expression of clock genes within the SCN, and the overall expression of these genes was reduced by 18% to 40% of entrained values. Arrhythmia in per1, per2, and bmal1 was due to reductions in the amplitudes of their oscillations. We suggest that these data are compatible with an amplitude suppression model in which light induces singularity in the molecular circadian pacemaker.

Physiologic correlates of t'ai chi chuan.

BACKGROUND: T'ai chi chuan, the ancient Chinese martial art, is practiced by millions of people worldwide and is an activity of moderate intensity that involves slow, circular movements. Evidence of substantial health benefits of t'ai chi chuan is emerging, however, the physiologic mechanisms are not well-understood. T'ai chi chuan masters routinely report sensing qi or internal energy flow, particularly in the hands. The purpose of this case study was to determine whether physiologic responses normally associated with thermoregulation are activated during a basic t'ai chi chuan exercise. METHODS: Trials consisted of three focus periods and one withdraw period (during which the subject withdrew internal energy in the hands), each followed by a rest period. Measurements included infrared-thermography (IR), thermocoupled temperature measures, and laser Doppler flowmetry. RESULTS: Substantial increases in local palmar and face surface temperatures were observed with IR thermography during focus periods and substantial decreases were observed during the withdraw period. Fingertip surface baseline temperatures were 31.1°C for one trial, increased by 1.8°C during the focus period, and then decreased by 4.9°C during the withdraw period. A twofold increase in blood flow through fingertip regions paralleled changes in fingertip surface temperatures during focus periods. CONCLUSIONS: Changes in regional blood flow and surface temperatures closely paralleled onsets of focus, rest, and withdraw periods and appear to be volitional activations of known vasomotor mechanisms underlying non-hairy skin regions such as the hands and face. Changes in blood flow through these vascular structures are generally autonomic thermoregulatory responses, not normally under voluntary control, but may also represent a relaxation response.

Light induces c-fos and per1 expression in the suprachiasmatic nucleus of arrhythmic hamsters.

Locomotor activity rhythms in a significant proportion of Siberian hamsters (Phodopus sungorus sungorus) become arrhythmic after the light-dark (LD) cycle is phase-delayed by 5 h. Arrhythmia is apparent within a few days and persists indefinitely despite the presence of the photocycle. The failure of arrhythmic hamsters to regain rhythms while housed in the LD cycle, as well as the lack of any masking of activity, suggested that the circadian system of these animals had become insensitive to light. We tested this hypothesis by examining light-induced gene expression in the suprachiasmatic nucleus (SCN). Several weeks after the phase delay, arrhythmic and re-entrained hamsters were housed in constant darkness (DD) for 24 h and administered a 30-min light pulse 2 h after predicted dark onset because light induces c-fos and per1 genes at this time in entrained animals. Brains were then removed, and tissue sections containing the SCN were processed for in situ hybridization and probed with c-fos and per1 mRNA probes made from Siberian hamster cDNA. Contrary to our prediction, light pulses induced robust expression of both c-fos and per1 in all re-entrained and arrhythmic hamsters. A separate group of animals held in DD for 10 days after the light pulse remained arrhythmic. Thus, even though the SCN of these animals responded to light, neither the LD cycle nor DD restored rhythms, as it does in other species made arrhythmic by constant light (LL). These results suggest that different mechanisms underlie arrhythmicity induced by LL or by a phase delay of the LD cycle. Whereas LL induces arrhythmicity by desynchronizing SCN neurons, phase delay-induced arrhythmicity may be due to a loss of circadian rhythms at the level of individual SCN neurons.

Heat extraction through the palm of one hand improves aerobic exercise endurance in a hot environment.

In situations where the accumulation of internal heat limits physical performance, enhanced heat extraction from the body should improve performance capacity. The combined application of local subatmospheric pressure (35-45 mmHg) to an entire hand (to increase blood volume) and a heat sink (18-22 degrees C) to the palmar surface were used to draw heat out of the circulating blood. Subjects walked uphill (5.63 km/h) on a treadmill in a 40 degree C environment. Slopes of the treadmill were held constant during paired experimental trials (with and without the device). Heat extraction attenuated the rate of esophageal temperature rise during exercise (2.1 +/- 0.4 degrees and 2.9 +/- 0.5 degrees C/h, mean +/- SE, with and without the device, respectively; n = 8) and increased exercise duration (46.1 +/- 3.4 and 32.3 +/- 1.7 min with and without the device, respectively; n = 18). Hand cooling alone had little effect on exercise duration (34.1 +/- 3.0, 38.0 +/- 3.5, and 57.0 +/- 6.4 min, for control, cooling only, and cooling, and subatmospheric pressure, respectively; n = 6). In a longer term study, nine subjects participated in two or four trials per week for 8 wk. The individual workloads (treadmill slope) were varied weekly. Use of the device had a beneficial effect on exercise endurance at all workloads, but the benefit proportionally decreased at higher workloads. It is concluded that heat can be efficiently removed from the body by using the described technology and that such treatment can provide a substantial performance benefit in thermally stressful conditions.

Light pulses do not induce c-fos or per1 in the SCN of hamsters that fail to reentrain to the photocycle.

Circadian activity rhythms of most Siberian hamsters (Phodopus sungorus sungorus) fail to reentrain to a 5-h phase shift of the light-dark (LD) cycle. Instead, their rhythms free-run at periods close to 25 h despite the continued presence of the LD cycle. This lack of behavioral reentrainment necessarily means that molecular oscillators in the master circadian pacemaker, the SCN, were unable to reentrain as well. The authors tested the hypothesis that a phase shift of the LD cycle rendered the SCN incapable of responding to photic input. Animals were exposed to a 5-h phase delay of the photocycle, and activity rhythms were monitored until a lack of reentrainment was confirmed. Hamsters were then housed in constant darkness for 24 h and administered a 30-min light pulse 2 circadian hours after activity onset. Brains were then removed, and tissue sections containing the SCN were processed for in situ hybridization. Sections were probed with Siberian hamster c-fos and per1 mRNA probes because light rapidly induces these 2 genes in the SCN during subjective night but not at other circadian phases. Light pulses induced robust expression of both genes in all animals that reentrained to the LD cycle, but no expression was observed in any animal that failed to reentrain. None of the animals exhibited an intermediate response. This finding is the first report of acute shift in a photocycle eliminating photosensitivity in the SCN and suggests that a specific pattern of light exposure may desensitize the SCN to subsequent photic input.

Glucocorticoids influence brain glycogen levels during sleep deprivation.

We investigated whether glucocorticoids [i.e., corticosterone (Cort) in rats] released during sleep deprivation (SD) affect regional brain glycogen stores in 34-day-old Long-Evans rats. Adrenalectomized (with Cort replacement; Adx+) and intact animals were sleep deprived for 6 h beginning at lights on and then immediately killed by microwave irradiation. Brain and liver glycogen and glucose and plasma glucose levels were measured. After SD in intact animals, glycogen levels decreased in the cerebellum and hippocampus but not in the cortex or brain stem. By contrast, glycogen levels in the cortex of Adx+ rats increased by 43% (P < 0.001) after SD, while other regions were unaffected. Also in Adx+ animals, glucose levels were decreased by an average of 28% throughout the brain after SD. Intact sleep-deprived rats had elevations of circulating Cort, blood, and liver glucose that were absent in intact control and Adx+ animals. Different responses between brain structures after SD may be due to regional variability in metabolic rate or glycogen metabolism. Our findings suggest that the elevated glucocorticoid secretion during SD causes brain glycogenolysis in response to energy demands.

Role of melanopsin in circadian responses to light.

Melanopsin has been proposed as an important photoreceptive molecule for the mammalian circadian system. Its importance in this role was tested in melanopsin knockout mice. These mice entrained to a light/dark cycle, phase-shifted after a light pulse, and increased circadian period when light intensity increased. Induction of the immediate-early gene c-fos was observed after a nighttime light pulse in both wild-type and knockout mice. However, the magnitude of these behavioral responses in knockout mice was 40% lower than in wild-type mice. Although melanopsin is not essential for the circadian clock to receive photic input, it contributes significantly to the magnitude of photic responses.