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Profound effects of spaceflight on the physiology of humans and non-human animals are well-documented but incompletely explored. Current goals to undertake interplanetary missions increase the urgency to learn more about adaptation to prolonged spaceflight and readaptation to Earth-normal conditions, especially with the inclusion of radiation exposures greater than those confronted in traditional, orbital flights. The 30-day-long Bion M-1 biosatellite flight was conducted at a relatively high orbit, exposing the mice to greater doses of radiation in addition to microgravity, a combination of factors relevant to Mars missions. Results of the present studies with mice provide insights into the consequences on brain function of long-duration spaceflight. After landing, mice showed profound deficits in vestibular responses during aerial drop tests. Spaceflown mice displayed reduced grip strength, rotarod performance, and voluntary wheel running, each, which improved gradually but incompletely over the 7-days of post-flight testing. Continuous monitoring in the animals’ home cage activity, in combination with open-field and other tests of motor performance, revealed indices of altered affect, expressed as hyperactivity, potentiated thigmotaxis, and avoidance of open areas which, together, presented a syndrome of persistent anxiety-like behavior. A learned, operant response acquired before spaceflight was retained, whereas the acquisition of a new task was impaired after the flight. We integrate these observations with other results from Bion-M1’s program, identifying deficits in musculoskeletal and cardiovascular systems, as well as in the brain and spinal cord, including altered gene expression patterns and the accompanying neurochemical changes that could underlie our behavioral findings.

Bites of tiger spiders belonging to Poecilotheria genus cause moderate to severe pain and long-lasting local or generalized muscle cramps in humans. Bites occur in regions of the spiders' natural habitat, India and Sri Lanka, but the popularity of these colorful tarantulas as pets leads to reports of envenomation cases worldwide. Treatment is predominantly symptomatic and often inadequate since there is almost no clinical or toxicology research data available, and physicians outside India or Sri Lanka typically have no experience in treating such cases. We report toxicity studies of venom from nine Poecilotheria species in laboratory mice (Mus musculus Balb/C males). LD50 values are 5-14 mg of lyophilized crude venom per 1 kg (i.v.). The major symptoms of envenomation include tonic-clonic seizures, jerks, characteristic motor stereotypy, and hyperalgesia and point to voltage-gated sodium channels as a potential target of the venom components. Poecilotheria fasciata venom effects were studied in detail at a sub-lethal dose of 5 mg/kg (LD50 = 12 mg/kg). 13 widely used pharmacological agents (atropine, chloropyramine, chlorpromazine, diazepam, ethanol, flupirtine, haloperidol, ketotifen, lamotrigine, oxcarbazepine, tolperisone, xylazine, and CaCl2) were checked for ability to suppress the envenomation symptoms. Chlorpromazine (10 mg/kg, i.p.), oxcarbazepine (60 mg/kg, p.o.), tolperisone (50 mg/kg, s.c.) and xylazine (2.5 mg/kg, i.p.) were found effective as a pretreatment to mitigate muscle cramps and motor stereotypy. When administered after envenomation chlorpromazine (5 mg/kg, i.v.) effectively reduced the cramps, while oxcarbazepine (30 mg/kg, i.v.) and xylazine (1 mg/kg, i.v.) suppressed the stereotypy.

Introduction Implantable telemetry enables continuous monitoring of physiological functions in freely moving animals and can greatly complement pharmacological research. Despite its miniaturization, a sensor/transmitter constitutes 5% or more of a mouse's bodyweight. The aim of the present study was to evaluate whether factors related to the presence of a probe/transmitter influence the ambulatory activity, strength, agility, or operant, motivated behaviors of this small rodent. Methods Adult male mice (C57BL/6 N, 22–25 g, 9–10 weeks; implanted n = 26, intact n = 45) were evaluated during week-long tests, conducted three and eight weeks after surgical implantation of the PA-C10 blood pressure probe. An open field test, grip force measurement, Rotarod test were performed, followed by 7-day continuous monitoring of spontaneous wheel running activity and positively reinforced operant conditioning in an automated data collection system. Results An implanted blood pressure transmitter did not affect behavior of mice in the open field test, on the Rotarod or their grip force, compared to unoperated controls. Voluntary wheel running distance was reduced three, but not eight weeks after implantation. Three weeks after the surgery, performance in the positively reinforced operant conditioning in operated mice was slightly decreased compared to intact animals, while retention and acquisition of a 2nd, reversal-learning task eight weeks after the surgery were unaffected. Discussion We conclude that an implantable transmitter may have detectable effects in the first few weeks following implantation on some elements of mouse behavior. With sufficient recovery, mice perform comparably to unoperated controls in tests of strength, endurance, agility and learned operant behavior.

Russian Abstract: Сжигание попутного нефтяного газа (ПНГ) является экономически и экологически нерациональным способом его утилизации. Доступность данных по сжиганию ПНГ меняется в зависимости от страны; часто статистика ограничена или нерелевантна. На сегодняшний день спутниковый мониторинг является единственным инструментальным методом измерения объёмов сжигания газа, не связанным с деятельностью нефтегазовых компаний. Однако разработка методики мониторинга сталкивается с необходимостью обработки больших массивов данных и введения алгоритма оценки объёмов сожжённого газа. В данной работе описан алгоритм, разработанный для сенсора VIIRS, и приведён анализ полученных данных по территории России за период наблюдений. English Abstract: Incineration of associated petroleum gas (APG) is an economically and environmentally unsustainable way to utilize it. Availability of APG incineration data varies by country; often statistics are limited or irrelevant. At present, satellite monitoring is the only instrumental method for measuring gas flaring volumes that is not related to the activities of oil and gas companies. However, the development of a monitoring methodology is faced with the need to process large amounts of data and introduce an algorithm for estimating volumes of burned gas. This paper describes an algorithm developed for the VIIRS sensor, and an analysis of the data obtained on the territory of Russia for the observation period.

Russian Abstract: Лавинообразное увеличение объема спутниковых данных, получаемых современными сенсорами, стало основным препятствием к их использованию для ручного обнаружения рыболовных судов промысловыми агентствами и другими организациями. В связи с этим потребовалась разработка алгоритма и реализующей его автоматической системы детектирования ночных судовых огней по спутниковым данным и анализа их распределения. В данной работе представлен алгоритм детектирования ночных судовых огней по спутниковым данным сенсора VIIRS, описана программная система, реализующая разработанный алгоритм, описаны разработанные методы и средства анализа распределения ночных судовых огней, представлены результаты апробации разработанных методов. English Abstract: The avalanche increase in the amount of satellite data received by modern sensors has become a major obstacle to their use for manual detection of fishing vessels by fishing agencies and other organizations. In this regard, it was necessary to develop an algorithm and an automatic system for detecting night ship lights using satellite data and analyzing their distribution. This paper presents an algorithm for detecting night ship lights using satellite data from the VIIRS sensor, describes a software system that implements the developed algorithm, describes the developed methods and tools for analyzing the distribution of night ship lights, and presents the results of testing the developed methods.

Kounis syndrome (KS) was originally described as acute coronary syndrome (ACS) in context of an allergic reaction. It is commonly associated with insect stings or food ingestion. KS has also been reported with commonly used antibiotics but there remains a lack of data to characterize and manage

Background Photothrombosis is a minimally invasive method for induction of cortical ischemia. However, different ways of applying some methods to assess photothrombosis-induced damage need to be developed. New Methods We applied the tongue protrusion test and H&E staining of brain sections to detect ischemic damage after photothrombosis. Evaluation of the local status of the BBB using Evans blue dye was proposed. We also assessed the sensitivity of the grid-walk test. Moreover, we examined the interchangeability of MRI and TTC staining to measure lesion volume. Results We evaluated ischemic outcomes at 24 h after photothrombosis in mice. The tongue protrusion test did not reveal impairments of the neurological status whereas the grid-walk test showed the high sensitivity. Using histological techniques, we determined the reduction in the number of neurons with normal morphology in the penumbra. 3D reconstruction of the brain, which reflected Evans blue dye distribution in the nervous tissue, revealed BBB disruption in areas remote from the ischemic core. We also showed the strong correlation between damage volumes assessed by MRI and TTC staining. Comparison with Existing Methods The present work demonstrates the efficacy of the classical histological approach and TTC staining that are more affordable than MRI and immunohistochemical methods. Detection of 3D distribution of Evans blue dye in the brain in contrast to its total extraction reveals BBB damage in details. Conclusions We proposed the simple methods for describing the severity of brain ischemia at the cellular and whole organism levels without significant labor and financial expenditures.

Myasthenic crisis is a life-threatening condition commonly associated with respiratory failure and may present in unusual ways. However, there is paucity in the literature about the cardiac manifestations of myasthenia gravis. We present a case of a 61-year-old male who presented to the emergency room with upper respiratory infection symptoms who soon thereafter suffered sudden cardiac arrest. He was found to have shortened PR interval pre and post arrest onelectrocardiogram (EKG). Only past medical history, discovered post cardiac arrest, was myastenia gravis. All other causes of cardiac arrest were ruled out, and it was deemed to be due to a manifestation of myastenia gravis. The patient was treated with intravenous steroids and plasmapheresis with resolution of shortened PR interval. It is hypothesized that striatial muscle antibodies may trigger inflammation in cardiac muscle and cause conduction abnormalities. In addition, anti-Kv1.4 antibodies have been associated with EKG abnormalities, including QT prolongation and T-wave inversion. To our knowledge, we are the first to report myasthenic crisis manifesting with isolated cardiac arrest with pulseless electrical activity and a shortened PR interval.

International audience; When tested on the treadmill mice do not display a graded increase of heart rate (HR), but rather a sharp shift of cardiovascular indices to high levels at the onset of locomotion. We hypothesized that under test conditions cardiovascular reaction to physical load in mice is masked with stress-associated HR increase. To test this hypothesis we monitored mean arterial pressure (MAP) and heart rate in C57BL/6 mice after exposure to stressful stimuli, during spontaneous locomotion in the open-field test, treadmill running or running in a wheel installed in the home cage. Mice were treated with beta1-adrenoblocker atenolol (2mg/kg ip, A), cholinolytic ipratropium bromide (2mg/kg ip, I), combination of blockers (A+I), anxiolytic diazepam (5mg/kg ip, D) or saline (control trials, SAL). MAP and HR in mice increased sharply after handling, despite 3weeks of habituation to the procedure. Under stressful conditions of open field test cardiovascular parameters in mice were elevated and did not depend on movement speed. HR values did not differ in I and SAL groups and were reduced with A or A+I. HR was lower at rest in D pretreated mice. In the treadmill test HR increase over speeds of 6, 12 and 18m/min was roughly 1/7-1/10 of HR increase observed after placing the mice on the treadmill. HR could not be increased with cholinolytic (I), but was reduced after sympatholytic (A) or A+I treatment. Anxiolytic (D) reduced heart rate at lower speeds of movement and its overall effect was to unmask the dependency of HR on running speed. During voluntary running in non-stressful conditions of the home cage HR in mice linearly increased with increasing running speeds. We conclude that in test situations cardiovascular reactions in mice are governed predominantly by stress-associated sympathetic activation, rendering efforts to evaluate HR and MAP reactions to workload unreliable.

A new technique to investigate laser driven ion acceleration with fully isolated, mass-limited glass spheres with a diameter down to 8 μ m is presented. A Paul trap was used to prepare a levitating glass sphere for the interaction with a laser pulse of relativistic intensity. Narrow-bandwidth energy spectra of protons and oxygen ions have been observed and were attributed to specific acceleration field dynamics in case of the spherical target geometry. A general limiting mechanism has been found that explains the experimentally observed ion energies for the mass-limited target.

A suppression of transverse proton divergence by a localization of high-energy electron bunch generated by an interaction between an intense laser and a foil target is investigated in this paper. When an intense laser illuminates a foil target, electrons are accelerated longitudinally by the ponderomotive force and produce a strong magnetic field. The electrons are confined by the magnetic field and an electric field is generated locally. Protons are extracted and mainly accelerated longitudinally by the local electric field. Consequently, the transverse divergence of high-energy protons is successfully suppressed.