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The actions exerted by waves on a coastal structure very much depend upon hydrodynamic processes that originate on shallow waters; even though significant progresses have been made in the last few years towards a full understanding of wave breaking, design work is still largely based on classical stability formulas. The recent availability of reliable models based on the numerical integration of full Navier-Stokes equations provides an important tool, but the evaluation of forces on vertical structures in shallow waters is still a particularly delicate application because of the complex hydrodynamic issues involved. The paper presents deals with the numerical simulation of wave effects on front of a vertical obstacle on a sloping bottom, with the objective of clarifying some physical issues which are relevant towards the applicability of numerical Navier-Stokes simulation as a design tool.

SARS-CoV-2 infection is associated with thyroid disorders. It has been reported that myxedema coma (MC) can be complicated with COVID-19. COVID-19-related thyroid disorders consist of a broad spectrum of thyroid dysfunction, from thyrotoxicosis to decompensated hypothyroidism. It is possible that both primary and central thyroid disorders are induced by COVID-19 due to systemic inflammatory and immune responses. We experienced two cases in which patients with COVID-19 developed MC with central hypothyroidism. It is likely that MC affected the severity of COVID-19. It is necessary to consider the existence of MC during SARS-CoV-2 infection. We propose the potential mechanisms.

Bacteria has been known to grow in pipes of water distribution systems and bottled drinking water. Its growth in reusable drinking water bottles is not clear even though they have become more popular and used by children and adults daily everywhere. This study found that there is an extremely high level of bacteria content and a rapid microbial growth in reusable drinking water bottles. The bacteria content tested by heterotrophic plate count (HPC) is in a range of 0-2.4x105 CFU/mL with an average of about 34,000 bacteria counts/ml for bottles used by children and 75,000 bacteria counts/ml for bottles used by adults. Bacteria number can quickly increases to 1-2 million counts/ml in the bottles one day later. Considering the high level of HPC bacteria content in the reusable drinking water bottles, it may be necessary to have some control measures to reduce the bacteria level and to minimize the associated likely health risk of the disease spreading since many people use reusable water bottles every day. 

The paper presents and develops the issue of Cumulative Effect Assessment (CEA) in the Environmental Impact Assessment (EIA) screening procedure established by the State and Regional regulations In Italy. In the period 2001-15 in the territory of the Venice province (north east Italy, Veneto region) n. 328 projects (and the related environmental preliminary/definitive studies) were applied to competent Authorities (6% to the State, 39% to the Region and 55% to the Province). All the Environmental Impact Studies (EISs) and Environmental Preliminary Studies (EPSs) referring to the this territory officially applied to competent Authorities in the period 2001-2010, have been analysed with focus on the identification and assessment of cumulative effects (CEs); the projects considered and analysed for this purpose comprise a total of n. 181 EIA screening and ordinary procedures; the remaining 147 projects in the period 2011-15 (for a total of 328) are here considered only for statistical reason to an update assessment of project typologies in the same territory. The methodology applied for the analysis of the sample of environmental studies in the period 2001-10 refers to that presented by Cooper and Sheate (2002) with modifications. The investigation has been developed looking for the way in which the topic is performed by practitioners in the environmental studies as from qualitative as well as quantitative point of view. Specific attention has been paid to waste management plants which are always subject to EIA screening procedure since 2008 according to Directive 97/11/EEC and in case to the whole EIA procedure. The approach proposed by Lombardia Region (North Italy; 2010) for EIA screening procedure of waste management plants has been applied to identify CEs and modified according to the characteristics of the considered territory; it allows the performance of the project-based approach and must be completed with a regional-based approach (Dubè, 2003). The proposed approach can be useful in case of waste management and IPPC (Integrated Pollution Prevention and Control, Directive 96/61/EEC, amended with Directives 2008/1/EC and 2010/75/EU) plants to define the financial warranties required for the authorization of operative activity of the plants to cover potential environmental damages produced in cases of accidents and other conditions as required in Europe (art. 14 Directive 2004/35/EC on environmental liability). Several project categories were chosen and their EISs analysed as an exemplificative case according to the potential generation of cumulative impacts and the characteristics of the territory. With reference to the completed procedures where the competent Authority presented a final judgement, it has been observed that the CEA has been seldom developed due to not compulsory legal requirements as already observed by Burris and Canter (1997). Moreover, when it is considered, the methodology is limited and not systemized. Indices of impact have been identified according to emission for the main environmental components focussed with the analysis of the pressure factors of the plants. The study points out the need to analyse and evaluate the cumulative effects (CEs) at a strategic level (within the Strategic Environmental Assessment-SEA- procedure) with a view to preparing the study for EIA/EPS framework procedure for the projects derived from the corresponding plan/program. A sound knowledge of the considered territory and in particular of its pressure sources is of main importance for CEA assessment and impacts’ prevention. Geographic Information Sytesm (GIS) application is strongly needed for pressure sources’ census and control data storing

Assuming that the road infrastructure has been implemented in accordance with specifications and standards, poor adhesion between the two layers of asphalt mix can be a significant cause of pavement problems. The general problem observed with the weak adhesion between the layers is the slip failure. Slipping disruption in areas where transport acceleration increases, in areas where acceleration decreases or may occur in bumps. One of the criteria and a test method for measuring adhesion resistance between the hot mix asphalt layers is needed to improve the surface finish. The main objective of this study is to determine the effect of reducing the coefficient of friction between asphalt layers in the displacement of asphaltic layers. Because performing experimental experiments in the country is a deterrent to this goal, the use of analytical and numerical methods has been shown to play an important role in conducting studies. Therefore, in this paper, using vehicle simulation in ABAQUS software and analyzes, it has been found that decreasing the coefficient of friction (adhesion reduction) increases the interlayer deformation, which causes the surface of the pavement to fail. Three different thicknesses for asphalt cladding, including 4, 6, and 7 centimeters, and three different thicknesses for roller concrete layers of 18, 20 and 22 centimeters are used. Modeling and analysis of pavements with finite element method has been performed and the depth of the asphalt and tensile strain slope is calculated at the maximum level. The results show that the type of asphalt mix has a high impact on the amount of sloping and tensile strain at the maximum level. So that under different conditions it is estimated to be about 2-3 times in the amount of rotation at the surface. Also, the amount of groove and strain in the middle of the procedure is increased by a thickness of 11% the thickness of the roller concrete thickness has not changed, but the surface strain has been reduced by 9%.

Pines have been discovered to die in the Alps. In any place of skiing, you can find dried pine trees from 2x to 20 meters high. In each zone of visibility of the forest mass of such pines, there are from 1 to 90%. I wonder if science deals with this issue

The main purpose of this investigation is to inspect the innovative conception of the magneto hydrodynamic (MHD) nanoparticles of single wall carbon nanotubes base on the fluids (water, engine oil, and ethylene, glycol and kerosene oil) between two rotating parallel plates. Carbon nanotubes (CNTs) parade sole assets due to their rare structure. Such structure has significant optical and electronics features, wonderful strength and elasticity, and high thermal and chemical permanence. The heat exchange phenomena is deliberated subject to thermal radiation. Kerosene oil is taken as based nano fluids because of its unique attention due to their advanced thermal conductivities, exclusive features, and applications. The fluid flow is presumed in steady state. With the help of suitable resemblance variables, the fundamental leading equations have been converted to a set of differential equations. To obtain the solution of the modeled problem, the homotopic approach has been used. The influence of imbedded physical variables upon the velocities and temperature profiles are defined and deliberated through graphs. Moreover, for the several values of relevant variables, the skin fraction coefficient and local Nusselt number are tabulated. Plots have been presented in order to examine how the velocities and temperature profile get affected by various flow parameters.

Graphical abstract Biodegradation of implanted gold in human tissue. TEM images reveal markedly biodegradation of implanted gold and re-crystallization of dissolved gold as nanoparticle of different size, shape and crystallinity. Highly crystalline icosahedral Au nanoparticle and the corresponding power spectrum are shown on top. Background: Despite the importance of biodegradation for the durability of metal prosthesis and the widely use of gold implants, there exist a lack of knowledge regarding the stability of pure gold in tissue. Methods: We studied biodegradation of grids of pure gold, nickel, and copper as well as middle ear prosthesis of gold, platinum or titanium. Metals were implanted into rat skin and humans. Dissolution and re-crystallization process of the metals was analysed using SEM, TEM, power spectra as well as elemental analysis by EDX and EELS/ESI. Results: Biodegradation of gold was detected, presumably by solving and re-precipitation of gold around implants. Gold cluster, nanoparticles, and mesostructures were detected, formed by dissolution and re-crystallization process. This process results into a migration of gold into the farer off tissue. Cellular filaments as biomolecular templates facilitate the formation of mesostructures. Loss of function of middle ear prosthesis by biodegradation is caused by chronic inflammation and fibrosis. Indeed, similar processes were detected with platinum, but in a very lower level. Conclusion: Noble metal implants undergo biodegradation in oxidative environment in tissue. The dissolution – recrystallization process can be explained by enzyme catalysed redox processes comprising reactive oxygen species and reduction agents as ascorbic acid present in cells and body tissue. Enymes like myeloperoxidase inside lysosomes of inflammatory cells produce hypochloride ions and H2O2 which can dissolve the gold. General significance: The crucial role of the specific chemical environments of gold implants in tissue for their chemical stability and durability of function has been demonstrated. Due to widely use and importance of gold implants, this finding is of general interes.

The demand for materials and devices that are capable of controlling heat flux has attracted many interests due to desire to attain new sources of energy and on-chip cooling. Excellent properties of DNA make it as an interesting nanomaterial in future technologies. In this paper, we aim to investigate the thermal flow through two sequence combinations of DNA, e.g, (AT)4 (CG)4 (AT)4 (CG)4 and (CG)8 (AT)8. Two interesting phenomena have been observed respectively. In the first configuration, an oscillatory thermal flux is observed. In this way, an oscillating heat flux from a stationary spatial thermal gradient is provided by varying the gate temperature. In the second configuration, the system behaves as a constant heat current source. The physical mechanism behind each phenomenon is identified. In the first case, it was shown that the transition between thermal positive conductance and negative differential conductance implies oscillatory heat current. In the latter, the discordance between the phonon bands of the two coupled sequences results in constant thermal flow despite of increasing in temperature gradient.

Introduction: High proportion of stroke survivors have impaired functional mobility and decrease in overall quality of life (QoL). Transcranial direct current stimulation (tDCS) (non-invasive brain stimulation) and over-ground walking task (OGWT) (functional task-oriented training) have been suggested to improve functional mobility and QoL of stroke survivors. Hence, this study determined the efficacy of tDCS (anodal and cathodal) with OGWT on functional mobility and QoL of stroke survivors. Materials and methods: Seventy eight (78) stroke survivors were randomised into three groups: anodal group (anodal tDCS with OGWT); cathodal group (cathodal tDCS with OGWT) and control group (OGWT only). Participants had two sessions of intervention per week for six weeks. Functional mobility was assessed using 10 meter walk test (10MWT) measuring steps, time and velocity while QoL was measured using Stroke Specific QoL (SSQoL) scale. Significance level was set at p < 0.05. Results: Participants (46 males) were aged 56.78 ± 10.24 years. The groups were matched for functional mobility and QoL at baseline and only work/productivity domain of SSQoL showed statistically significant difference (p = 0.028). Each group showed statistically significant improvement between baseline and post-intervention scores of items in functional mobility (p ≤ 0.001) and total SSQoL (p ≤ 0.001). Anodal group showed better statistically significant improvement in step (p = 0.008), time (p = 0.024), velocity (p = 0.001) and total SSQoL (p = 0.016) among the groups when the mean differences were compared. Conclusion: tDCS with OGWT is efficacious in improving functional mobility and QoL of stroke survivors. Specifically anodal tDCS with OGWT showed better clinical improvement in step, time, velocity and QoL in stroke survivors.

Carbon Nano fibers (CNFs) have recently attracted a lot of attention due to their widespread range of technological applications attributed to their unique physical and chemical properties, such as, small size, high strength, high adsorption linked with their large specific surface area, high temperature tolerance and corrosion resistance. CNFs have been used in energy conversion and storage, reinforcement of composites and self-sensing devices. The complete removal of entrapped metallic impurities and amorphous carbon incorporated with CNFs has been a long-standing issue. We have developed a new approach for preparing graphitic CNFs and its activation of surface area by purification. This approach entails Thermal Decomposition (TD) based synthesis of CNFs from organic solid waste, such as, stems of rice plants. CNFs are synthesized from organic waste precursor (Rice Stems) at 900 oC under inert atmosphere. The active surface area was measured using a Surface Area Analyzer. Morphology of CNFs was studied with using SEM and XRD. The SEM image shows that the synthesized CNFs have diameter ranging within 45-60 nm.

The non-force magnetic fields were first predicted by Chandrasekhar in 1956 in his well-known published work [1]. Since then there have appeared a large number of theoretical studies [5,6,15,17] with the research into various aspects of physical manifestations of non-force magnetic fields. However by now their existence in the technical physics and in laboratory experiments has not been experimentally confirmed [30]. Nevertheless the indistinct presence on the Earth of such fields was, in a sense, discovered in the natural electromagnetic field much earlier.

A quantum mechanical model that considers tunneling and inelastic scattering has been applied to explain the hole transfer reaction from a G (Guanine) base to a GGG base cluster through a barrier of Adenine bases, (A)n (n = 1-16). For n = 1, the ratio of tunneling to inelastic scattering is about 6, which is sharply decreased to around 0.23 and 5.23 × 10-8 for n = 4 and 16 respectively, suggesting dominance of inelastic scattering for n ≥ 4. As in experiment, the calculated product yield ratios (PGGG) exhibit a strong distance dependence for n < 4, and a weak distance dependence for n ≥ 4. We also predict conditions under which oscillatory or non-oscillatory charge transfer (CT) yield are expected.

The natural ferromagnetic resonance (NFMR) in cast glass-coated amorphous magnetic microwires has been studied theoretically and experimentally. The NFMR reveals large residual stresses appearing in the microwire core in the course of casting. These stresses, together with the magnetostriction, deteRmine the magnetoelastic anisotropy. Beside the residual internal stresses, the NFMR frequency is influenced by external stresses applied to the microwire or to the composite containing the latter (the so-called stress effect). The dependence of the NFMR frequency on the deformation of the microwires is proposed to be used in the distant diagnostics of dangerous deformations of critical infrastructure objects such as bridges, dams, wind turbine towers, skyscrapers, stack-furnaces, embankments, etc. To this end, fragments of magnetic microwires will be embedded in the bulk of concrete structures or fixed on their surface during construction or after it by means of coating with a special concrete-adhesive plaster. Further, these structures are periodically irradiated with microwaves from a radar at frequencies close to the original NFMR, and the presence of latent dangerous deformations of the concrete structure is judged by the NFMR frequency shift.

In the beginning of 1973 in the USSR the study of possibility of LJE designing was conducted. The reflector, located in the tail of the rocket prototype, concentrated the obtained radiation in air and ensured micro-burst that the reactive thrust was created. The successful results of different models of the reflectors tests, which were at the same time the laser light receivers, had been obtained. One should note that all experiments pointed out above were conducted with the use of electric discharge CO2- lasers with power up to 10 kW, while for the injection into orbit of different highly and technologically effective equipment (global network connections, Internet, photo-monitoring of Earth surface, debris cleaning) the radiated power substantially higher is required. Thus, for example, for SC launching with the weight 1000 kg the laser with power not less than 15 MW is necessary [1,2].

This paper is a study of nuclear reactions involving 12c + 12c nuclei carried out with a heavy-ion nucleus-nucleus optical potential derived from a new M3Y-type effective interaction, called B3Y-Fetal, within the framework of optical model at the incident energies of 112, 126.7, 240, 300, 1016 MeV. Folding analyses of the differential cross sections associated with the elastic scattering of the nuclear system, determined at these incident energies with four B3Y-Fetal-based folded potentials constructed from double folding model, have shown the DDB3Y1- and BDB3Y1-Fetal potentials to be the best in excellent agreement with previous work done with the M3Y-Reid. The agreement of the B3Y-Fetal with the famous M3Y-Reid effective interaction, which is also used for folding analysis in this work, is further buttressed and well-established by the findings of this study Herein, the values of the renormalization factor, NR ranging from 1.1117 to 0.8121, obtained with the B3Y-Fetal have been found to be slightly higher, with lower reaction cross sections, aR = 1418 - 1047 millibarns, than NR = 0.9971 - 0.8108 obtained with the M3Y-Reid effective interaction whose accompanying reaction cross sections, being higher, range from 1431 to 1050 millibarns. This depicts the B3Y-Fetal as having a better performance. Additionally, results of folding analyses have shown the best-fit folded potentials, DDB3Y1- and BDB3Y1-Fetal potentials to be in agreement at all incident energies, implying that the cold nuclear matter has an underlying soft equation of state.

Since the discovery of glare illuminators, considerable efforts have been devoted to achieving a breakthrough of high light intensity on the order of magnitude. In this paper, we prepared strong flash blinding agents for the first time by using aluminum powder, oxidant, and adhesive as the main materials, and tris-(8-hydroxyquinolinato) aluminum (Al2Q3), triazoindolizine, or nano zinc oxide, etc. as electronic output brightener after mixing and granulation according to the developed formulation. It was discovered that the luminescence intensity was related to the thermal effect of the substance while the brightener only served as an auxiliary brightening effect to achieve energy non-destructive conversion. With the same formula, the luminescence intensities of glaze agents with ADN and potassium perchlorate as oxidants were slightly higher than that of ammonium perchlorate oxidant; the brightening effect of nano-zinc oxide was slightly higher than those of tris-(8-hydroxyquinolinato) aluminum (Al2Q3) and triazoindolizine. The luminescence intensity of the substance with a high thermal effect value was high, but the luminescence time was slightly short. Under identical conditions, the luminescence effect of nano-aluminum powder was obviously better than that of micro-aluminum powder with the highest luminescence intensity of 3.9 × 1010 ~ 1.9 × 1011 cd and the luminescence time of 39 - 48 ms. The effects of shell material and structure and the effect of heat-induced mode on the luminescence intensity were also investigated. The luminescence intensity of the glare agent with a high shell strength was high, but the luminescence time was slightly short. Moreover, the energy level of the brightener is excited under the induction of high temperatures, which leads to a blue shift to promote the chemical reaction of the material in a favorable direction. Finally, the optical radiation of the thermally induced high-temperature combustion system was analyzed from the aspects of thermal effect, combustion temperature, and chemiluminescence effect. A way to improve the optical radiation intensity of a high-temperature combustion system was proposed.

Oguta LGA is surrounded by 44 oil wells located around different communities. Preliminary investigations indicated that crude wastes were not properly managed and oil spillage occurred regularly in the LGA. Therefore, assessment of both radionuclide contents in yam matrix and health risks in Oguta was carried out to determine possible radiological health risks associated with improper management of crude wastes, and also evaluate haematological health profile in the LGA for future reference and research. A well calibrated NaI (Tl) detector was deployed for the radiological investigation, and about 5 ml of blood samples were collected from 190 participants each from Oguta and the control LGAs for haematological assessment. Mean activity concentrations due to 40K, 226Ra and 232Th in yam samples from Oguta LGA were 189.99 ± 59.14 Bqkg-1, 23.75 ± 5.69 Bqkg-1 and 30.99 ± 9.51 Bqkg-1, respectively while mean activity concentrations due to natural radionuclides in yam samples from control LGA were 110.40 ± 78.53 Bqkg-1, 10.12 ± 3.34 Bqkg-1 and 18.39 ± 8.74 Bqkg-1 for 40K, 226Ra and 232Th, respectively. Committed effective dose equivalent values in Oguta and the control LGAs were 704.95 ± 183.30 μSvy-1 and 403.65 ± 172.19 μSvy-1, respectively which are less than world average value of 1.1 mSvy-1. Crucially, one-way ANOVA at α0.05 has indicated that effects of radiological parameters due to natural radionuclides in yam from Oguta are significantly different from effects of radiological parameters due to natural radionuclides in yam from the control LGA. However, the percentage contributions of natural radiation exposures to incidence of cancer in Oguta and the control LGAs are just 1.7% and 1.4%, respectively, and haematological investigations have shown that overall health of the communities in the study LGAs has not been compromised due to environmental and human factors. Hence, natural radioactivity may have been elevated in Oguta but the concentration levels are not yet alarming. Radiological health risks could result from consistent exposure to those natural radionuclides in the long term.

Background: Post exposure chemoprophylaxis can prevent human immunodeficiency virus (HIV) infection in risk healthcare workers; however routine adoptions of these practices by the workers have been limited. Objective: To assess knowledge and attitude of health workers on HIV post-exposure prophylaxis and exposure to sharp injuries in Dessie referral hospital. Methods: Across-sectional study was conducted on 422 health care workers of Dessie referral Hospital. The study subjects were selected by proportional allocation of each sample in its respective department/ward. Simple random sampling method was used to select study participants. The data was cleaned coded and analyzed by using statistical package for social sciences (SPSS) version 23. Finally the result was presented by graphs, pie chart and statements. Results: A total of 422 study subjects were participated in the study. Among 422 participants 72.5% had good knowledge of post exposure prophylaxis for HIV and the rest 27.5% had poor knowledge of post exposure prophylaxis for HIV. Among 422 study participants 75.2% had positive attitude towards PEP. 283(67.1%) of them had exposure to sharp injuries. Conclusion: Generally most of health care workers had good knowledge about post exposure prophylaxis against HIV/AIDS. This study had shown that a significant number of individuals had a negative attitude with regard to post exposure prophylaxis. Therefore, formal training that aims to improve attitudes and support to improve PEP implementation and completion are needed. 

Plasma stability is the biggest challenge facing the nuclear fusion industry. One of the best methods of stability study is magnetohydrodynamic (MHD) equations, which has two linear and nonlinear states. Usually linear stability analysis is used to describe the MHD state, which is obtained by linearizing nonlinear equations. The reactor under study is the W7-X reactor, which is an optimal example of a stellaratoric system. The question raised in this research is how to create suitable conditions for the formation of plasma and heat transfer produced by the melting reaction. Many efforts have been made in this direction, but still the record holder for plasma state maintenance belongs to the international ITER project and around 1000. However, IPP researchers at the Max Planck Institute in Germany (maker of the W7-X reactor) predicted that by 2020 they would produce a pulse of 30 minutes. The numerical method is used to investigate the stability of the reactor. In this paper, boundary conditions were expressed in terms of resistance wall. With the help of the mathematical Matlab software, magnetic field values ​​were obtained from experimental reports extracted from the Max Planck Institute for various values ​​of β. From the values ​​obtained, it was concluded that the appropriate field value is β = 5 according to the ideal MagnetoHydroDynamic state and the interval defined by the Max Planck Institute.