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Object and purpose of research. This paper presents analytical estimates for emission characteristics of foreign low-probability-of-intercept (LPI) radars. It also gives a quantitative assessment to the possibility of detecting the operation of these radars by standard naval EW tools. Subject matter and methods. This paper reviews the publications of leading foreign experts in order to analyse performance parameters of existing foreign LPI radars and ESM tools. Emission characteristics of these “stealthy” radars in marine conditions were calculated by means of the four-beam model of electromagnetic wave scattering over an underlying surface developed by Krylov State Research Centre researchers. Main results. The study yielded a quantitative estimate for the possibility to detect the emission of radar homing head for RBS-15 anti-ship missile by standard naval tools of radioelectronic surveillance. Conclusion. The study has shown that ESM tools currently available with foreign navies cannot reliably detect the operation of LPI radars.

BackgroundThe diagnostic yield of brain Magnetic Resonance Imaging (MRI) in spontaneous intracerebral hemorrhage (ICH) is unclear. We performed both an independent single-center retrospective cohort study and a meta-analysis to assess the detection rate of secondary lesions on MRI in patients with spontaneous ICH.MethodsIn the retrospective cohort study, we examined 856 consecutive patients with spontaneous ICH. Brain MRI scans on admission and follow-up were assessed for secondary lesions. We also examined clinical and CT radiographic variables associated with secondary lesions in univariable analysis. In the meta-analysis we searched PubMed and EMBASE for articles investigating the secondary lesion detection rate on brain MRI in spontaneous ICH. Random-effects models were used to calculate the pooled estimate of secondary lesion detection rate. The meta-analysis used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.ResultsOf the 856 patients with ICH, 481 (56%) had at least one brain BRI performed [70±14 years, 270(56% male)]. 462(54%) had an admission MRI and 138(16%) had both admission and follow-up MRIs. The detection rate of secondary lesions on admission MRIs was 24/462(5.2%). 4/127(3.1%) patients with a negative admission MRI had a lesion identified on follow-up MRI. No clinical or radiographic variables were associated with a secondary lesion on MRI using univariable analysis. The meta-analysis included 5 studies total (4 identified in the PubMed and EMBASE searches as well as our own cohort study) comprising 1147 patients with spontaneous ICH who underwent brain MRI. The pooled detection rate of secondary lesions was 11% (95%CI: 7-16%).ConclusionsNo predictors of secondary lesion detection were identified in our cohort study. Prospective studies are required to better understand the diagnostic utility of MRI in spontaneous ICH.

Introduction: Coma is an unresponsive state of disordered consciousness characterized by impaired arousal and awareness. While coma has been studied in the context of traumatic brain injury, the epidemiology and pathophysiology of coma in ischemic stroke has been underexplored. We sought to characterize the incidence and clinical features of coma as a presentation of large vessel occlusion (LVO) stroke. Methods: Individuals who presented with LVO were identified from July 2018 to December 2020. Coma was defined as an unresponsive state of impaired arousal and awareness, operationalized as a score of 3 on NIHSS item 1a: responds only with reflex motor or autonomic effects or totally unresponsive, flaccid, and areflexic. Results: A total of 28/638 (4.4%) patients with large vessel occlusion stroke were identified as presenting with coma. The median age was 65 (IQR 48-78), and 57% were female. The median NIHSS was 32 (IQR 29-34). Occlusion locations included basilar (10), vertebral (2), P1 posterior cerebral (2), internal carotid (4), M1 middle cerebral (6), and M2 middle cerebral arteries (4). In all 14 patients with anterior LVO, the acute LVO was unilateral. Of these 14, 6 had evidence of acute or chronic stroke involving the contralateral hemisphere; 1 experienced seizure; 1 experienced cardiac arrest; and 1 had chronic occlusion of the contralateral ICA. Overall, 20/28 died during the admission. Of those who died, 9 presented with anterior LVO and 11 with posterior LVO. Eight patients were treated with EVT. For those not treated, reasons included established infarct with ASPECTS Conclusions: It is not uncommon for patients with LVO stroke to present with coma, and 65% of patients not treated with EVT had delayed presentations or large established infarcts, emphasizing the need for maintaining a high index of suspicion. While more commonly thought to result from posterior LVO, coma in our cohort was similarly likely to result from anterior LVO. Further study of these patients may shed light on the pathophysiology of coma. Efforts to improve early diagnosis and care are crucial given their poor outcomes.

Introduction: Patients with baseline disability account for up to one-third of stroke presentations. Despite growing evidence supporting their benefit from endovascular thrombectomy (EVT), there remains controversy in treatment selection. We compared the long-term outcomes and the likelihood of comfort care for large vessel occlusion (LVO) stroke patients who presented with severe baseline disability treated with EVT versus medical management. Methods: Individuals who presented with LVO were identified from a prospectively maintained database from January 2017 to December 2020. Severe baseline disability was defined as modified Rankin Scale (mRS) 3-5. Delta mRS was defined as the difference between baseline and 90-day mRS. Logistic and ordinal regressions were performed to evaluate the relationships between EVT and outcomes. Results: A total of 175/1007 (17%) patients were identified with severe baseline disability. The median age was 82 (IQR 70-89), and 59% were female. Thirty-two (18%) patients with severe baseline disability were treated with EVT. EVT was independently associated with improved delta mRS (B=-1.048; 95%CI=-1.777,-0.318; p=0.005) when accounting for age and NIHSS. However, EVT did not reduce the odds of transitioning to comfort care (aOR=0.794; 95%CI=0.347,1.818; p=0.585) when accounting for age and NIHSS. Seventy-six (43%) patients with severe baseline disability were transitioned to comfort care. Of the 99 patients who were not transitioned to comfort care, 18 were treated with EVT. In this subgroup not transitioned to comfort care, EVT was independently associated with improved delta mRS (B=-2.794; 95%CI=-4.002,-1.586; p Conclusions: Among patients with severe baseline disability, EVT is associated with less post-stroke accumulated disability without limiting transitions to comfort care. EVT is compatible with goal-concordant care in patients with severe baseline disability; it should not be routinely withheld on the sole basis of baseline disability.

Interaction of circularly polarized laser pulses with spherical nano-droplets generates nanometer-size magnets with lifetime on the order of hundreds of femtoseconds. Such magnetic dipoles are close enough in a cluster target and magnetic interaction takes place. We investigate such system of several magnetic dipoles and describe their rotation in the framework of Lagrangian formalism. The semi-analytical results are compared to particle-in-cell simulations, which confirm the theoretically obtained terrahertz frequency of the dipole oscillation.

An analytical model has been developed for the generation of a superstrong quasi-stationary magnetic field (up to several GG) in the focal waist of an ultra-intense short circularly polarised laser pulse interacting with a gas-cluster target. The rotation of relativistic electrons around the ionised core of the cluster has been shown to produce a magnetic moment and a quasi-stationary magnetic field. With a large number of nanoclusters, the magnetic field occupies the entire focal volume with a characteristic spatial scale of tens of micrometers and exists during the cluster expansion time (i.e., several picoseconds).

Here, we describe a case of a woman suspected to have an anterior cerebral artery (ACA) aneurysm that was ultimately found to have an azygous ACA shield. This benign entity highlights the importance of thorough investigation with cerebral digital subtraction angiography (DSA). This 73-year-old female initially presented with dyspnea and dizziness. CT angiogram of the head suggested an incidental 5 mm ACA aneurysm. Subsequent DSA demonstrated a Type I azygos ACA supplied by the left A1 segment. Also noted was a focal dilatation of the azygos trunk as it gave rise to the bilateral pericallosal and callosomarginal arteries. Three-dimensional visualization demonstrated a benign dilatation secondary to the four vessels branching; no aneurysm was noted. Incidence of aneurysms at the distal dividing point of an azygos ACA ranges from 13% to 71%. However, careful anatomical examination is imperative as findings may be a benign dilatation for which case intervention is not indicated.

Aim. To evaluate the efficiency of bone repair on a critical-sized rat calvarial defect model using our original xenogeneic bone mineral, widely established Geistlich Bio-Oss®, and autologous bone graft.Materials and Methods. We created a critical-sized calvarial defect in Sprague-Dawley rats (n = 48) and then divided them into 4 groups (unfilled defect, autologous bone graft, Geistlich BioOss® and our original xenogeneic bone mineral, 12 rats per group). Rats were sacrificed upon 4 and 12 months (6 rats per time point) with the following excision of the implant and adjacent tissues. 3D structure, extent of mineralisation, and bone volume were measured by means of microcomputed tomography. Microanatomy of the explants and adjacent tissue was investigated by haematoxylin and eosin staining.Results. The highest and the lowest bone volume was expectedly detected when the defect was filled with the autologous bone graft or remained unfilled, respectively. Replacement of the defect by the original bone mineral entailed better regeneration as compared to Geistlich Bio-Oss. Bone mineral density, bone thickness and the extent of mineralisation did not differ significantly between the experimental groups and were close to the positive control values, indicating efficient bone repair.Conclusions. Original xenogeneic bone mineral promotes induction of bone regeneration as compared to Geistlich Bio-Oss®, a commercially available bone mineral widely used in the clinical practice.

Laser wakefield acceleration (LWFA) using PW-class laser pulses generally requires cm-scale laser–plasma interaction Rayleigh length, which can be realized by focusing such pulses inside a long underdense plasma with a large f-number focusing optic. Here, we present a new PW-based LWFA instrument at the SG-II 5 PW laser facility, which employs f/23 focusing. The setup also adapted an online probing of the plasma density via Nomarski interferometry using a probe laser beam having 30 fs pulse duration. By focusing 1-PW, 30-fs laser pulses down to a focal spot of 230 µm, the peak laser intensity reached a mild-relativistic level of 2.6 × 1018 W/cm2, a level modest for standard LWFA experiments. Despite the large aspect ratio of >25:1 (transverse to longitudinal dimensions) of the laser pulse, electron beams were observed in our experiment only when the laser pulse experienced relativistic self-focusing at high gas-pressure thresholds, corresponding to plasma densities higher than 3 × 1018 cm−3.

It has been shown that the irradiation of a gas target with nanoclusters by a short (tens of femtoseconds), relativistically intense, circularly polarized laser pulse results in the appearance of magnetic dipoles, which are oriented in the direction of the propagation of the laser pulse and produce a quasi-static regular magnetic field with an amplitude to tenths of the field of the initial laser pulse. At a sufficient concentration of clusters, after the end of the laser pulse, the magnetic moments of the dipoles undergo vibrations and the magnetic field oscillates, which is accompanied by the appearance of a short (few-cycle) secondary terahertz radiation. The condition for the appearance of such a short terahertz pulse is that the cyclotron frequency of an electron on average over the volume of the magnetic field is higher than the inverse lifetime of the cluster.

Lynx1 is a GPI-tethered protein colocalized with nicotinic acetylcholine receptors (nAChRs) in the brain areas important for learning and memory. Previously, we demonstrated that at low micromolar concentrations the water-soluble Lynx1 variant lacking GPI-anchor (ws-Lynx1) acts on α7-nAChRs as a positive allosteric modulator. We hypothesized that ws-Lynx1 could be used for improvement of cognitive processes dependent on nAChRs. Here we showed that 2 µM ws-Lynx1 increased the acetylcholine-evoked current at α7-nAChRs in the rat primary visual cortex L1 interneurons. At higher concentrations ws-Lynx1 inhibits α7-nAChRs expressed in Xenopus laevis oocytes with IC50 ~ 50 µM. In mice, ws-Lynx1 penetrated the blood-brain barrier upon intranasal administration and accumulated in the cortex, hippocampus, and cerebellum. Chronic ws-Lynx1 treatment prevented the olfactory memory and motor learning impairment induced by the α7-nAChRs inhibitor methyllycaconitine (MLA). Enhanced long-term potentiation and increased paired-pulse facilitation ratio were observed in the hippocampal slices incubated with ws-Lynx1 and in the slices from ws-Lynx1-treated mice. Long-term potentiation blockade observed in MLA-treated mice was abolished by ws-Lynx1 co-administration. To understand the mechanism of ws-Lynx1 action, we studied the interaction of ws-Lynx1 and MLA at α7-nAChRs, measured the basal concentrations of endogenous Lynx1 and the α7 nAChR subunit and their association in the mouse brain. Our findings suggest that endogenous Lynx1 limits α7-nAChRs activation in the adult brain. Ws-Lynx1 partially displaces Lynx1 causing positive modulation of α7-nAChRs and enhancement of synaptic plasticity. Ws-Lynx1 and similar compounds may constitute useful hits for treatment of cognitive deficits associated with the cholinergic system dysfunction.

The paper considers differential equations with fractional derivatives used for describing the functioning of an oscillator with viscoelastic damping as well as diffusion processes. On the basis of a mathematical model with fractional derivatives, the present research deals with the qualitative parameter of the model to confirm the consistency of the given process with experimental data. An analysis of recent publications on this topic has been carried out and a method of obtaining a qualitative assessment of the obtained mathematical model is given. The presented approach was tested in a numerical experiment using the developed software.

An optical diagnostic based on resonant absorption of laser light in a plasma is introduced and is used for the determination of density scale lengths in the range of 10 nm to >1 μm at the critical surface of an overdense plasma. This diagnostic is also used to extract the plasma collisional frequency, allowing inference of the temporally evolving plasma composition on the tens of femtosecond timescale. This is found to be characterized by two eras: the early time and short scale length expansion (L 0.1λ); this is consistent with a hydrogen plasma decoupling from the bulk target material. Density gradients and plasma parameters on this scale are of importance to plasma mirror optical performance and comment is made on this theme.

Metabolic chambers are routinely used for urine collection in rodents. In mice, due to small urination volume, evaporation in the metabolic chambers (≈50%) distorts diuresis and urinalysis parameters. We have developed a new technique of bladder catheterization enabling long-term accurate and contamination-free urine collection in awake male and female mice for 30 days or longer. Daily diuresis in catheterized mice was twice higher as compared to metabolic cages. The twofold difference in urine recovery was preserved when the circadian variation of diuresis, the effects of furosemide, desmopressin and water load were estimated using the two techniques. Urine osmolarity, urinalysis, and microbiological parameters evidence higher quality of the catheter-collected urine. Using phenol red, we demonstrate utility of our technique for pharmacokinetic studies. 30 days after the surgery the catheters were patent and had minimal impact on the animals' heath. Bladder catheterization is a useful tool for physiological, pharmacological, and toxicological studies.

Introduction: The component of the lymphopharyngeal ring is the lingual tonsil (LT), located on the root of the tongue. With pathological changes in the lymphoid tissue of the pharynx, surgical removal of the tonsils, as a result of increased antigenic load, a compensatory increase in LT is observed – «lingual tonsillar hypertrophy». This is observed against the background of age-related involutive changes, when the remaining elements of the lymphopharyngeal ring begin to perform anti-antigenic and adaptive activity. The processes taking place in, the structure of the LT, which is familiar to the body, changes - the receptor apparatus creates pathological impulses from the organ. The severity of clinical manifestations correlates with the degree of increase in LT. The emphasis on these manifestations, psychosomatic conditions, create a complex of pathological sensations that violate the quality of patients’ life. The goal and objectives of the study are aimed at improving the quality of patients’ life with lingual tonsil hypertrophy (LTH), by developing effective methods of diagnosis and treatment, assessing the role of the immunoregulatory shift in the pathogenesis of LTH of the possibility of their correction by the action of a physical factor (cold destruction). Materials and methods: When examining 850 people who underwent complex research and instrumental diagnostics in connection with the pathology of ENT organs, 119 people (the main group) were diagnosed with different degrees of LTH, with control of 30 healthy people. Cryosurgical treatment was offered to 76 patients who used the method for treating of lingual tonsil hypertrophy by cryodestruction using a hook-shaped applicator with a heat-insulating nozzle on the back surface, an individual polyethylene cap, and a cryoapparatus. Results and discussions: With LTH, an increase in the volume and mass of tissues forming the morphological basis of the tonsil was detected: the main substance was an increase in the number and size of layers of coarse fibrous fibers, fields of fat cells, and the growth of mucous glands. The mucous membrane, thinning, undergoes dystrophic-degenerative changes. The rate of proliferation correlates with the severity of inflammation, the causes of which are multifactorial, individual. There is an increased sensitivity reaction to microbial and household allergens, an increase in the content of antibodies in the blood to LT tissues, a change in microbiocinosis of the pharyngeal mucosa, and vegetation of non-resident microflora. As a result of cryosurgical treatment in 56 (73.68%) cases, a decrease in the volume of LT tissue was observed. The deep layers, partially absorbed, were replaced by healthy tissues, the surface layers were rejected with the formation of an atrophic scar or regenerate, the structure of which was close to organotypic. The cause of pathological impulse was eliminated, clinical indicators were normalized, the quality of life of patients was improved. Conclusions: LTH should be considered as a continuation of the development of a productive process associated with immunoregulatory changes in chronic infectious and allergic conditions. Local cryogenicity on LTH was accompanied by normalization of the structure of its own substance, LT, and a decrease in inflammatory changes in surrounding tissues. The development of inflammatory changes in LT was a local manifestation of a general disturbance in the functioning of the immune defense system. Achieving a persistent positive effect in the treatment of LTH requires an integrated approach with mandatory systemic immune correction and hormonal correction.

The photon yield obtained during the betatron motion of electrons in the ion cavity is proportional to the number of such oscillations (or wiggling). In the case of high repetition rate laser systems the pulse energy is very limited, thus the laser pulse has to be tightly focused in order to achieve high peak intensity in the focus. In this way narrow gas jets are used, which results in short acceleration length of electrons, thus in low number of betatron oscillations. In order to increase the number of x-ray photons a mixture of clusters and gas target can be used, where the space-charge of nano-meter size droplets forces the electrons to oscillate at much higher frequency leading to the emission of more photons. In this work we present the interaction of such cluster targets with linearly polarized laser pulses and describe some possible positive effects when circular polarization is used.

A hybrid mechanism of ion acceleration is investigated which demonstrates the higher spectral density of protons at high energies. The interaction of few-cycle terrawatt laser pulses with near-critical density gas target is studied with the help of two-dimensional particle-in-cell simulation. The generation of few MeV protons with high spectral concentration near cutoff is attributed to the propagation of solitary waves in the decaying density profile of the gas jet. Plasma dynamics at longer time scale is explained by semianalytical modeling and conditions for solitary wave breaking are presented.

One of the fundamental tasks in behavioral neurophysiology is the study of movement control. During past decades, methodological arsenal in this field was limited to the expert's visual observation, especially in the open field paradigm when animals can move, groom, rare or explore objects. In the past few years, the massive adoption of machine learning and artificial intelligence has led to revolutionary changes in the field. Here we present a new and user friendly approach to the analysis of the behavior of rodents, based on a pre-trained and continuing to learn neural network, which is capable of exhibiting a high degree of flexibility and good level of performance. Open field behavior of two groups (juvenile and adult) female wistar rats has been recorded. Human expert identified several behavioral patterns for farther deep machine learning, based on open source Orange SqueezeNet, a pre-trained neural network. In addition, we used the transfer learning technique with three more layers over SqueezeNet with 10-fold cross validation. The correctness of the assessments, made by the neural network consisted 92 ± 3% based on unbiased and double-blinded expert evaluation. Moreover, younger and older rat groups revealed significant difference in such behavioral patterns as moving and hole testing, identified by the network. We conclude that our system is demonstrative, does not require high programming skills, looks intuitive, easy to use, is based on an open source resource, therefore, can be recommended as behavioral research tool and an educational platform.