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The authors wish to thank J.M. Torrejón for the organization of the Athena-multi-messenger Workshops, held on November 27 - 29, 2018, in Alicante, Spain and on 5 May 2020 - 6 May 2020 in videoconference., In this paper we explore the scientific synergies between Athena and some of the key multi-messenger facilities that should be operative concurrently with Athena. These facilities include LIGO A+, Advanced Virgo+ and future detectors for ground-based observation of gravitational waves (GW), LISA for space-based observations of GW, IceCube and KM3NeT for neutrino observations, and CTA for very high energy observations. These science themes encompass pressing issues in astrophysics, cosmology and fundamental physics such as: the central engine and jet physics in compact binary mergers, accretion processes and jet physics in Super-Massive Binary Black Holes (SMBBHs) and in compact stellar binaries, the equation of state of neutron stars, cosmic accelerators and the origin of Cosmic Rays (CRs), the origin of intermediate and high-Z elements in the Universe, the Cosmic distance scale and tests of General Relativity and the Standard Model. Observational strategies for implementing the identified science topics are also discussed. A significant part of the sources targeted by multi-messenger facilities is of transient nature. We have thus also discussed the synergy of Athena with wide-field high-energy facilities, taking THESEUS as a case study for transient discovery. This discussion covers all the Athena science goals that rely on follow-up observations of high-energy transients identified by external observatories, and includes also topics that are not based on multi-messenger observations, such as the search for missing baryons or the observation of early star populations and metal enrichment at the cosmic dawn with Gamma-Ray Bursts (GRBs)., Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature., This research has been supported by the European Union’s Horizon 2020 programme under the AHEAD (grant agreement number 654215) and AHEAD2020 project (grant agreement n. 871158). FJC and SMN acknowledges funding under project RTI2018-096686-B-C21 funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe”, and by the Unidad de Excelencia María de Maeztu, ref. MDM-2017-0765.

Currently, eculizumab is the main effective treatment for paroxysmal nocturnal hemoglobinuria (PNH). The aim of this randomized multicenter noninferiority study was to evaluate the efficacy and safety of the Biosimilar (Elizaria) in comparison with the Originator (Soliris) in patients with PNH. Biosimilar and Originator were administered at a dose of 600 mg weekly for 4 weeks at the initial stage in naive patients, as well as for maintenance therapy at a dose of 900 mg every 2 weeks in all patients. The primary endpoint was a comparative assessment of hemolytic activity based on the area under the lactate dehydrogenase (LDH) concentration–time curve during the maintenance therapy. Thirty-two (32) patients were randomized for therapy with Biosimilar (n = 16) or Originator (n = 16). The mean values of LDH concentration–time curve were similar in both treatment groups without statistically significant differences (p > 0.05). Evaluation of secondary endpoints has shown no statistically significant differences between the groups. Safety values were comparable in both treatment groups. The data obtained confirm that the Biosimilar is not inferior to the Originator in terms of the main efficacy parameter, and is also comparable with it in terms of safety and additional efficacy parameters. Clinicaltrials.gov identifier: NCT04463056

We describe the results for full-scale experimental test production of high-basicity sinter (basicity 2.0–5.0) at the Enakievo Metallurgical Plant Sinter Shop. As sinter basicity increased from 2.0 to 5.0, the iron content of the sinter decreased from 53.05% to 32.24%, and the ferrous oxide concentration decreased from 17.55% to 9.29%. However, the strength specifications of the sinter were improved: The concentration of 0–5-mm fines decreased from 19.32% to 15.89%, and the yield of +5 mm size class in a drum test increased from 65.9% to 72.3% through optimization of the sintering process parameters. The use of high basicity sinter in blast-furnace smelting reduced the specific consumption of lime in the blast-furnace charge from 233.9 kg/metric ton of cast iron (at sinter basicity 2.0) to 103.5 kg/metric ton (at basicity 4.5) and, correspondingly, the specific feed rate for coke during castiron production decreased from 538.1 kg/metric ton to 476.6 kg/metric ton.

Background Chlorhexidine gluconate (CHG) bathing of hospitalized patients may have benefit in reducing hospital-acquired bloodstream infections (HABSIs). However, the magnitude of effect, implementation fidelity, and patient-centered outcomes are unclear. In this meta-analysis, we examined the effect of CHG bathing on prevention of HABSIs and assessed fidelity to implementation of this behavioral intervention. Methods We undertook a meta-analysis by searching Medline, EMBASE, CINAHL, Scopus, and Cochrane’s CENTRAL registry from database inception through January 4, 2019 without language restrictions. We included randomized controlled trials, cluster randomized trials and quasi-experimental studies that evaluated the effect of CHG bathing versus a non-CHG comparator for prevention of HABSIs in any adult healthcare setting. Studies of pediatric patients, of pre-surgical CHG use, or without a non-CHG comparison arm were excluded. Outcomes of this study were HABSIs, patient-centered outcomes, such as patient comfort during the bath, and implementation fidelity assessed through five elements: adherence, exposure or dose, quality of the delivery, participant responsiveness, and program differentiation. Three authors independently extracted data and assessed study quality; a random-effects model was used. Results We included 26 studies with 861,546 patient-days and 5259 HABSIs. CHG bathing markedly reduced the risk of HABSIs (IRR = 0.59, 95% confidence interval [CI]: 0.52–0.68). The effect of CHG bathing was consistent within subgroups: randomized (0.67, 95% CI: 0.53–0.85) vs. non-randomized studies (0.54, 95% CI: 0.44–0.65), bundled (0.66, 95% CI: 0.62–0.70) vs. non-bundled interventions (0.51, 95% CI: 0.39–0.68), CHG impregnated wipes (0.63, 95% CI: 0.55–0.73) vs. CHG solution (0.41, 95% CI: 0.26–0.64), and intensive care unit (ICU) (0.58, 95% CI: 0.49–0.68) vs. non-ICU settings (0.56, 95% CI: 0.38–0.83). Only three studies reported all five measures of fidelity, and ten studies did not report any patient-centered outcomes. Conclusions Patient bathing with CHG significantly reduced the incidence of HABSIs in both ICU and non-ICU settings. Many studies did not report fidelity to the intervention or patient-centered outcomes. For sustainability and replicability essential for effective implementation, fidelity assessment that goes beyond whether a patient received an intervention or not should be standard practice particularly for complex behavioral interventions such as CHG bathing. Trial registration Study registration with PROSPERO CRD42015032523. Electronic supplementary material The online version of this article (10.1186/s12879-019-4002-7) contains supplementary material, which is available to authorized users.

The formation of micropinches and X-ray sources in low-voltage, laser-induced discharges with high rates of current rise is investigated.

This study deals with the flow induced by a rigid flat plate of finite length, initially touching a horizontal water surface, when it starts to move upwards with constant acceleration. In the present model, negative hydrodynamic pressures on the lower (wetted) surface of the plate are allowed, and thus, the water follows the plate due to the resulting suction force. The acceleration of the plate and the plate length are such that gravity, surface tension and viscous effects can be neglected during the early stages of the motion. Under these assumptions, the initial two-dimensional, potential flow caused by the plate lifting is obtained by using the small-time expansion of the velocity potential. This small-time solution is not valid close to the plate edges, as it predicts there singular flow velocities and unbounded displacements of the water-free surface. It is shown that close to the plate edges the flow is nonlinear and self-similar to leading order. This nonlinear flow is computed by the boundary-element method combined with a time-marching scheme. The numerical time-dependent solution approaches the self-similar local solution with time.

Calbindin (CB)-containing neurons in the cranial cervical, stellate, and celiac sympathetic ganglia of rats (n = 60) aged 3–90 days were studied using an immunohistochemical method. The results obtained demonstrated that the stellate ganglion contained the greatest proportion of CB-immunopositive neurons. The proportions of CB-immunopositive neurons in the para- and prevertebral sympathetic ganglia decreased with age. The formation of the group of CB-immunopositive neurons in sympathetic ganglia was complete by the end of the first month of life.

The morphological characteristics of TRPV1-immunoreactive neurons were studied in thoracic spinal nerve sensory ganglia in rats aged 10, 20, 30, 60, and 90 days in normal conditions and after chemical deafferentation by s.c. administration of capsaicin (100 mg/kg) on the second day of life. TRPV1-immunoreactive neurons differed in terms of their morphological characteristics: immunopositive cells were very small and small in size, and immunonegative cells were small, intermediate, and large in size. Treatment of neonatal rats with capsaicin changed the developmental dynamics of TRPV1-positive neurons, with a decrease in the mean cross-sectional area of cells and decreases in the numbers of these cells throughout the observation period.

The background electrical activity of neurons in the cranial cervical ganglion was studied in neonatal rats and in animals aged 10, 20, and 30 days and two and six months. All age groups showed a predominance of neurons with irregular activity and fewer neurons with spikes synchronized with respiration. In neonates and 10-day-old animals, neurons in the ganglion were characterized by low discharge frequencies. The discharge frequency increased significantly from age 20 days. Animals of this age and older showed neurons with spike activity synchronized with the ECG. The mean spike frequency in animals aged 30 days and two and six months showed no statistically significant differences. Thus, the pattern of neuron background activity was formed during ontogeny in rats by age 20 days. Final formation of the amplitude-frequency characteristics of neuron activity in the cranial cervical ganglion in rats was complete by the end of the first month of life.

The aim of the present work was to study the anatomical characteristics of the stellate ganglion (SG) and the morphometric properties of its neurons in rats of different age groups (neonatal and 10, 20, 30, 60, and 180 days) using anatomical and histological methods. The results identified three variants of the origins of branches from the medial border of the SG from the moment of birth. No differences between the right and left ganglia were seen. The size of the SG and its neurons increased during the first two months of life. The density of neurons on sections decreased from birth to age six months, while the number of neurons in the SG showed no significant change. Thus, the rat SG was formed by birth and the size and morphometric properties of its neurons finally stabilized at age two months.

The initial stage of unsteady two-dimensional flow caused by the impulsive horizontal motion of a floating circular cylinder is investigated by using methods of asymptotic analysis. Initially the cylinder is half-submerged and the liquid free surface is flat and horizontal. The liquid is of infinite depth. Then the cylinder suddenly starts to move horizontally with a speed given as a function of time. The liquid is assumed ideal and incompressible and its flow potential. The initial flow is provided by pressure-impulse theory, with an account of a possible separation of the liquid free surface from the trailing face of the rigid surface of the cylinder. The initial position of the separation point on the surface of the moving body is determined by using the condition that the fluid velocity is finite at the separation point (Kutta condition). The motion of the separation point along the surface of the cylinder is numerically determined with the help of the second-order outer solution of the problem and the Kutta condition at the moving separation point. It is shown that the length of the wetted part of the cylinder surface increases at a rate proportional to the speed of the cylinder. The speed of the separation point depends on the Froude number. The pressure on the wetted part of the cylinder can be below the atmospheric pressure for relatively high speed.

The hydrodynamic loads generated during the entry of a circular disk into deep water are evaluated with the help of the method of matched asymptotic expansions. It is assumed that the liquid is initially at rest and the disk is floating on the still liquid surface. Then the disk suddenly starts its downward motion. The study is carried out under the assumption of an ideal and incompressible liquid. Attention is focused on the initial stage of the entry process. The solution is sought in the form of an asymptotic expansion of the velocity potential with the non-dimensional displacement of the disk being a small parameter of the problem. Gravity and surface-tension effects are shown to be of minor significance. Owing to the flow singularity at the edge of the disk, an inner problem is formulated and its solution is matched with the second-order outer velocity potential to achieve a uniformly valid solution. It is shown that the initial asymptotics of the hydrodynamic loads involves terms with \({h^{-\frac{1}{3}}}\) and log h where h(t) is the non-dimensional displacement of the disk. Both terms are unbounded in the limit of small penetration depth of the disk. The theoretical estimates are validated versus fully nonlinear numerical simulations of the problem during the later stage of the process. It is shown that the derived asymptotic estimates remain accurate, even for moderate displacements of the disk. The relative difference between the theoretical estimate of the hydrodynamic force and its numerical prediction is less than 5% when the penetration depth is smaller than \({\frac{1}{20}}\) of the disk radius. A way to use the theoretical estimates for practical applications is proposed and comparisons with experimental data available in the literature are also presented.

The linear two-dimensional problem of hydroelastic waves reflected by a vertical wall is analysed. The fluid is of finite depth and is covered by an ice sheet. The fluid is assumed incompressible and inviscid. The ice sheet is assumed thin compared with both the water depth and wavelength of the incident wave. The deflection of the ice sheet is described by linear elastic plate theory, and the fluid flow by using the potential-flow model. The ice sheet extends infinitely and is clamped to the vertical-walled structure. The incident hydroelastic wave is regular. An analytic solution is found by integral-transform methods. The ice deflection, the vertical and horizontal forces acting on the wall and the bending stresses in the ice caused by the incident wave are determined. The forces on the wall are analysed in detail, and relevant physical parameters are varied for comparison. The phase shift between the incident and reflected wave amplitudes is found as part of the complete solution. It is shown that the ice clamping condition leads to a specific effect on the ice deflection.

A two-dimensional unsteady hydroelastic problem of interaction between surface waves and a moving vertical wall fixed on springs is studied. An analytical solution of the problem is constructed using a linear approximation, and a numerical solution within the framework of a nonlinear model of a potential fluid flow is found by a complex boundary element method. By means of analysis of the linear and nonlinear solutions, it is found that the linear solution can be used to predict some important characteristics of the wall motion and the fluid flow in the case of moderate wave amplitudes.

The incidental discovery of adrenal masses during modern diagnostic imaging is a common occurrence. These masses form part of a long differential diagnostic list; most often, they are benign adrenal adenomas, but their discovery requires a clinical evaluation that is sufficiently broad to exclude clinically silent endocrine disease, metastases to the adrenal gland in patients with suspected or known malignancies, and rare adrenocortical carcinomas. CT, MRI and nuclear medicine approaches have all been used to evaluate incidentally discovered adrenal masses. Each technology provides information that contributes to the noninvasive characterization of the majority of these neoplasms. Understanding of the modalities used to assess an unanticipated adrenal mass allows for more rapid diagnosis and cost avoidance in a condition that has been referred to as a 'disease' of modern imaging technology.

A 31-year-old woman was incidentally found to have a large right adrenal mass by computed tomography imaging and underwent a workup that included endocrinological evaluation and positron emission tomography imaging. Laboratory results revealed the mass to be non-functioning. Imaging studies revealed a 9-cm heterogeneous mass that was not FDG avid. Because of concern for adrenal cortical carcinoma, the patient underwent a successful right adrenalectomy. Pathology examination demonstrated an 11-cm circumscribed mass consisting of uniform spindle cells without nuclear pleomorphism, necrosis, or mitotic activity. The diagnosis of leiomyoma was supported by a panel of immunohistochemical stains. Adrenal leiomyomas have been reported in the literature, although most are small and not preoperatively suspicious for malignancy. This case illustrates that benign tumors such as leiomyomas, when large and heterogeneous on imaging, can clinically mimic adrenal cortical carcinomas and should be included in the differential diagnosis of adrenal incidentalomas.

This article describes an estimation method for the hull girder response of a ship due to springing. The linear and nonlinear springing effects on the hull girder are evaluated. Previous studies on the springing response focused mainly on the symmetric response, or vertical response. In this article, however, the springing analysis is extended to asymmetric responses, or horizontal and torsional responses. The Timoshenko beam model was used to calculate the hull girder response and the quadratic strip method was employed to calculate hydrodynamic forces and moments on the hull. To remove irregular frequencies, a rigid lid was adopted on the hull free surface level and hydrodynamic coefficients were interpolated for asymptotic values. Applications to two ships for the symmetric and asymmetric responses were carried out and the effect of springing responses is also discussed.

We theoretically and experimentally study electromagnetic properties of a novel mid-infrared metamaterial: optically thin silicon carbide (SiC) membrane perforated by an array of sub-wavelength holes. Giant absorption and transmission is found using Fourier transformed infrared (FTIR) microscopy and explained by introducing a frequency-dependent effective permittivity eeff(ω) of the perforated film. The value of eeff(ω) is determined by the excitation of two distinct types of hole resonances: delocalized slow surface polaritons (SSPs) whose frequencies are largely determined by the array period, and a localized surface polariton (LSP) corresponding to the resonance of an isolated hole. Only SSPs are shown to modify eeff(ω) strongly enough to cause giant transmission and absorption. Because of the sub-wavelength period of the hole array, anomalous optical properties can be directly traced to surface polaritons, and their interpretation is not obscured by diffractive effects. Giant absorbance of this metamaterial can be utilized in designing highly efficient thermal radiation sources.

The paper deals with the two-dimensional unsteady problem of the impact of a liquid parabola onto a rigid flat plate at a constant velocity. The liquid is assumed ideal and incompressible and its flow potential. The initial stage of the impact is the main concern in this study. The non-dimensional half-width of the contact region between the impacting liquid and the plate plays the role of a small parameter in this problem. The flow region is subdivided into four parts: (i) the main flow region, the dimension of which is of the order of the contact-region width, (ii) the jet-root region, where the curvature of the free surface is very high and the flow is strongly nonlinear, (iii) the jet region, where the flow is approximately one-dimensional, (iv) the far-field region, where the flow is approximately uniform at the initial stage of impact. A second-order solution in the main flow region has been derived and matched to the first-order inner solution in the jet-root region. The matching conditions provide an estimate of the dimension of the contact region for small time. Pressure distributions in both the main flow region and the inner region are derived. The accuracy of the obtained asymptotic formulae is estimated. The second-order hydrodynamic force acting on the plate is obtained and compared with available experimental data. A fairly good agreement is reported.

The two-dimensional unsteady problem of the impact of a vertical wall on a layer of a liquid which is mixed with air near the wall and does not contain air bubbles away from the wall is solved in a linear approximation. The gas-liquid mixture is modeled by a homogeneous, ideal, and weakly compressible medium with a reduced sound velocity dependent on the air concentration in the gas-liquid mixture. Outside the gas-liquid layer, the liquid is considered ideal and incompressible. During the initial stage of the impact, the liquid flow and the hydrodynamic pressure are determined using the linear theory of the potential motion of an inhomogeneous liquid. The dependence of the amplitude of the impact pressure along the wall on the air concentration in the gas-liquid layer and on the thickness of this layer is investigated. For a small relative thickness of the layer, the thin-layer approximation is used. It is shown that the solution of the original problem tends to the approximate solution as the thickness of the layer decreases. It is shown that the presence of the gas-liquid layer leads to wall pressure oscillations. Estimates are obtained for the pressure amplitude and the oscillation period.

A computational analysis of an elastic plate dropped against regular long waves is presented. The problem is considered within the linear potential-flow theory. The liquid flow is two-dimensional and the plate is modelled by an Euler beam. The analysis is based on the normal-mode method with hydroelastic behavior of the plate being of main interest. Different impact conditions are considered to study the dependence of the total energy of the plate–liquid system on impact geometry and plate properties. The contributions of kinetic and potential energies to the total energy are analyzed. It is shown that the kinetic part of the system energy is small at the instant of time when bending stresses in the beam approach their maximum values. Estimations of both the total energy and the maximum of bending stresses are presented. Most of the calculations are performed for the conditions of experiments carried out in MARINTEK. A range of the problem parameters is also considered, to reveal peculiarities of the unsteady interaction between a falling elastic plate and surface waves.

Within the framework of the acoustic approximation a solution of the plane nonstationary problem of impact on a fluid boundary is found. The fluid occupies the lower half-plane and consists of two layers with given speeds of sound and densities. The upper layer has a constant depth and is bounded above by a plate with a given normal velocity. The solution is constructed using the Fourier and Laplace integral transforms. Numerical calculations are performed for piston impact across a rigid screen and the impact of a jet with an aerated head on a rigid wall. It is shown that the presence of an interlayer with reduced speed of sound and/or density considerably changes the evolution of the hydrodynamic pressure distribution over the impacting surface: the absolute pressure maximum decreases but pressures of significant amplitude are maintained for a longer time than for a homogeneous fluid.

The action of external periodic pressure on an elastic plate floating on the surface of a fluid assumed to be ideal and incompressible is examined by the method of normal modes in the linear formulation. The behavior of the matrix of coefficients of the hydrodynamic load on the plate is considered in detail for different frequencies. The behavior of the plate under localized periodic loading is compared for the cases of a heavy fluid with a finite or infinite depth and for a weightless infinite-depth fluid.

The initial stage of the plane unsteady flow caused by the impulsive vertical motion of a wedge initially floating on an otherwise flat free surface is investigated with the help of a combination of numerical and asymptotic methods. The liquid is assumed ideal and incompressible and its flow potential. Compressible effects give a negligible contribution to the flow close to the entering body at the stage considered in the present paper. The vertical velocity of the body is constant after the impulsive start. The flow domain is divided into an outer region, where the first-order solution is given by the pressure-impulse theory, and inner regions close to the intersection points between the free surface and the moving body. The relative displacement of the body plays the role of a small parameter. The inner solution is matched with the outer one. The outer solution is given in quadratures but the inner solution, which is shown to be nonlinear and self-similar, can be found only numerically. With the aim of deriving the inner solution, the inner region is divided into three parts. In the far-field zone the solution is given in terms of its asymptotic behavior while, in the jet region, attached to the wedge, the flow is described by a second-order shallow-water approximation. In the intermediate region a boundary-element method is used, which is suitably coupled with the solutions in both the jet and the far-field regions through an iterative pseudo-time stepping procedure. The procedure is dependent on the deadrise angle of the wedge. If the angle is equal or smaller than ?/4, eigensolutions appear in the far-field asymptotics and their amplitudes are recovered together with the solution. The approach is applied to different values of the wedge deadrise angle. The obtained results can be used to improve the prediction of the hydrodynamic loads acting on floating bodies, the velocity of which changes rapidly.

We report here immunohistochemical studies addressing substance P (SP)-containing neurons in the spinal nerve sensory ganglia of rats (n = 30) aged 10–90 days. The results showed that SP-immunopositive neurons are present in these ganglia from the moment of birth. The number of SP-containing neurons decreased with age to day 10 of life. SP-immunopositive neurons were very small and small cells.

The paper deals with the axisymmetric unsteady problem of the collision of two circular plates, one of which is located initially on the surface of a shallow liquid layer and another is falling down on it. The presence of air between the colliding plates is taken into account. Both the air and the liquid are assumed ideal and incompressible and their flows potential. The flows in the liquid layer and between the plates are assumed one-dimensional with corrections for three-dimensional effects close to the plate edges. The present study is focused on the stage of strong interaction between the plates, during which the floating plate is accelerated and the hydrodynamic pressure in the liquid layer takes its maximum value. A simplified model of this interaction is suggested. Velocities of the plates and the hydrodynamic pressure on the bottom of the liquid layer are analytically estimated and compared with experimental results. The model provides the maximum of the hydrodynamic pressure, which can be used at the design stage. It is shown that the air flow between the moving plates is of major importance to explain the low amplitude of the measured hydrodynamic pressures.

The paper deals with the plane problem of the hydroelastic behaviour of floating plates under the influence of periodic surface water waves. Analysis of this problem is based on hydroelasticity, in which the coupled hydrodynamics and structural dynamics problems are solved simultaneously. The plate is modeled by an Euler beam. The method of numerical solution of the floating-beam problem is based on expansions of the hydrodynamic pressure and the beam deflection with respect to different basic functions. This makes it possible to simplify the treatment of the hydrodynamic part of the problem and at the same time to satisfy accurately the beam boundary conditions. Two approaches aimed to reduce the beam vibrations are described. In the first approach, an auxiliary floating plate is added to the main structure. The size of the auxiliary plate and its elastic characteristics can be chosen in such a way that deflections of the main structure for a given frequency of incident wave are reduced. Within the second approach the floating beam is connected to the sea bottom with a spring, the rigidity of which can be selected in such a way that deflections in the main part of the floating beam are very small. The effect of the vibration reduction is quite pronounced and can be utilized at the design stage.

The problem of the behavior of a floating elastic plate in waves is solved numerically. The normal mode method is used. For a fluid of finite depth, the hydrodynamic coefficients are obtained in explicit form. Numerical results are compared with experimental data for the stress distribution in the plate and also with numerical results of other authors. The results are in good agreement for not very short waves. For incident waves whose wavelength is comparable with the length of the plate, a long-wave approximation of the solution is proposed. Within the framework of this approximation, the solution is given in analytical form.

A plane unsteady-state linear problem of the immersion of an elastic plate of finite length in an ideal incompressible weightless fluid is considered. The deflection of the plate and the velocity of its points are known at the initial moment of time. The fluid occupies the lower halfplane, and its boundary outside the plate is free. The plate which is the bottom of a structure immersed in the fluid with a constant velocity is modeled by an Euler beam. At the initial stage of immersion, when the displacement of the structure is much smaller than the length of the plate, the plate deflection and the distribution of bending stresses in it are determined. The model used allows one to estimate the maximum stresses occurring in the elastic plate during its impact on water and to predict the moment and site of its occurrence. Calculations are performed under the conditions of the experiment carried out in MARINTEX (Norway). Qualitative agreement between the numerical and experimental results is shown.

Impact by a box-like structure onto shallow water is analysed with the help of asymptotic methods. The analysis is based on both the asymptotic approach by Korobkin [1], which was derived originally for blunt-body impact, and the experimental results by Bukreev [2]. The flow region is divided into six parts: the region beneath the entering body, the region close to the bottom edge, the region of inertial flow of the liquid, the jet root, the splash jet and outer region. The flows inside each of the subdomains have their own peculiarities and are analysed separately. The matching conditions make it possible to obtain a uniformly valid asymptotic solution of the impact problem. The main attention is paid to the flow patterns and pressure distributions. It was found that the pressure inside the jet root can be comparable with the pressure beneath the entering body and can even exceed it. The effects of the shape of the body bottom and of the body flexibility on the liquid flow and the pressure distribution are investigated.

The problem of a symmetric wave impact on the Euler beam is solved by the normal modes method. The liquid is supposed to be ideal and incompressible. The initial stage of impact when hydrodynamic loads are very high and the beam is wetted only partially is considered. The flow of a liquid and the size of the wetted part of the body are determined by the Wagner approach with a simultaneous calculation of the beam deflection. The specific features of the developed numerical algorithm are demonstrated and the criterion of its stability is specified. In addition to a direct solution of the problem, two approximate approaches within the framework of which the dimension of the contact region is found ignoring the deformations of the plate are considered.

The results of study of frequency-tuned monochromatic x-ray source are reported. The source was developed on the basis of a vacuum diode with a laser-plasma cathode. The source proposed is particularly promising, if the range of x-ray energy higher than 5 keV is of interest. The source features a spectral brightness higher than 1019 photons/(cm2·s·sr·keV) and an x-ray pulse duration no larger than 10−8 s. An electromagnetic model of such a cathode is proposed and evaluated in order to assess the feasibility of an x-ray source with a laser-plasma cathode of higher performance. The possibility of using a ferroelectric electron emitter is discussed.

Incidentally discovered adrenal masses are detected in 0.35% to 5. 00% of patients imaged with computed tomography (CT) for reasons other than suspected adrenal pathology. Most small adrenal masses are benign, although malignant tumors/= 3 cm in diameter are well described. In the setting of normal adrenal hormonal secretion, the preferential accumulation of 131I-6beta-iodomethyl-norcholesterol (NP59) by adrenocortical tissues allows the distinction of adenomas from other space-occupying or destructive lesions, with diagnostic images being obtained in 100% of lesions2 cm. Although some lesions/= 2 cm have yielded nondiagnostic images, the frequency of this phenomenon and thus the utility of NP59 scintigraphy for the evaluation of small adrenal lesions has remained incompletely characterized. Between January 1976 and December 1994 a total of 166 patients with nonhypersecretory unilateral adrenal masses/= 3 cm in maximal diameter, discovered incidentally during CT examinations of the abdomen or chest for reasons other than clinically suspected adrenal disease, were studied with NP59 scintigraphy. Nonhypersecretory masses/= 1 cm,1 to/= 2 cm, and2 to/= 3 cm yielded diagnostic images in 52%, 89%, and 100% of patients, respectively. Lesions other than adenomas, including malignancies,1 to/= 2 cm and2 to/= 3 cm were present in 9% and 10% of patients, respectively. These findings emphasize the need to determine the nature of small incidentally discovered adrenal masses whose management may alter patient care and confirm the utility of NP59 scintigraphy to evaluate nonhypersecretory adrenal masses regardless of size.

With the advent of multi-detector row CT scanners, evaluation of the urothelium of the entire urinary tract with high-resolution thin sections during a single breath-hold has become a reality. Multidetector CT urography (MDCTU) is a single examination that allows evaluation of potential urinary tract calculi, renal parenchymal masses, and both benign and malignant urothelial lesions. Initial results with this new technique are encouraging. Current investigations of MDCTU focus on methods to improve opacification and distension of the upper urinary tract-the collecting systems, pelvis, and ureters. The role of abdominal compression, infusion of saline and/or furosemide, and optimal time delay of excretory phase imaging is being explored. Upper tract urothelial malignancies, including small lesions less the 5 mm in diameter, can be detected with high sensitivity. Methods to reduce radiation exposure are being explored, including split-bolus contrast injection techniques that combine nephrographic and excretory phases into a single phase. It is likely that in the near future, radiological evaluation of significant unexplained hematuria or of known or prior urothelial malignancy will consist of a single examination--MDCTU.

The purpose of this study was to determine the patterns of iodine-131 6β-iodomethylnorcholesterol (NP-59) imaging and the correlation with computed tomography (CT)-guided adrenal biopsy and follow-up in patients with bilateral adrenal masses. To this end we investigated a consecutive sample of 29 euadrenal patients with bilateral adrenal masses discovered on CT for reasons other than suspected adrenal disease. Adrenal scintigraphy was performed using 1 mCi of NP-59 injected intravenously, with gamma camera imaging 5–7 days later. In 13 of the 29 patients bilateral adrenal masses were the result of metastatic involvement from lung carcinoma (5), lymphoma (3), adrenocarcinoma of the colon (3), squamous cell carcinoma of the larynx (1), and anaplastic carcinoma of unknown primary (1). Among these cases the NP-59 scan demonstrated either bilaterally absent tracer accumulation (in eight, all with bilateral metastases proven by CT guided biopsy or progression on follow-up CT) or marked asymmetry of adrenocortical NP-59 uptake (in five). Biopsy of the adrenal demonstrating the least NP-59 uptake documented malignant involvement of that gland in five of five patients. In two patients an adenoma was found simultaneously in one adrenal with a contralateral malignant adrenal mass. In each of these cases, the adenoma demonstrated the greatest NP-59 uptake. In 16 patients diagnosis of adenoma was made on the basis of (a) CT guided adrenal biopsy of the gland with the greatest NP-59 uptake of the pair (n=4), or (b) adrenalectomy (n=2), or (c) absence of change in the size of the adrenal mass on follow-up CT scanning performed 6 months to 3 years later (n=10). It is concluded that differential in vivo functional information provided by NP-59 scintigraphy complements that derived from anatomic imaging and can be used in patients with bilateral adrenal masses to select which gland would be the best choice for further diagnostic invasive evaluation (e.g., adrenal biopsy) or may suggest the presence of bilateral adrenal metastases in patients with incidentally discovered, bilateral adrenal masses.

The characteristics of a 4000 SGL receiver of GLONASS artificial Earth satellite signals are experimentally investigated.