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A numerical computational treatment of transient electrically conducting fluid with an Arrhenius chemical reaction in the presence of Navier slip and Newtonian heating is obtained by using implicit finite difference scheme. A transverse magnetic field is applied to the flow direction due to the exothermic nature of the fluid. Numerical computation shows that, higher values of Frank-Kamenetskii parameter (λ) and Biot number (Br) significantly influence the transport phenomenon. Irrespective of smaller or larger time, Magnetic parameter (M) reduces velocity of the fluid as well as wall shear stress.

Lowland rivers and shallow aquifers are closely coupled and their interactions are crucial for maintaining healthy stream ecological functions. In order to explore river–aquifer interactions and lowland hydrological system in three Belgian catchments, we apply a combined approach of baseflow separation, impulse response modelling and time series analysis over a 30–year study period at catchment scale. Baseflow from hydrograph separation shows that the three catchments are groundwater-dominated. The recursive digital filter methods generate a smoother baseflow time series than the graphical methods, and yield more reliable results than the graphical ones. Impulse response modelling is applied with a two–step procedure. The first step where groundwater level response is modelled shows that groundwater level in shallow aquifers reacts fast to the system input, with most of the wells reaching their peak response during the first day. There is an overall trend of faster response time and higher response magnitude in the wet (October–March) than the dry (April–September) periods. The second step of baseflow response modelling shows that the system response is also fast and that simulated baseflow can capture some variations but not the peaks of the separated baseflow time series. The time series analysis indicates that components such as interflow and overland flow, contribute significantly to stream flow. They are somehow included as part of the separated baseflow, which is likely to be overestimated from hydrograph separation. The impulse response modelling approach from the groundwater flow perspective can be an optional method to estimate the baseflow, since it considers some level of the physical connection between river and aquifer in the subsurface. Further research is however recommended to improve the simulation, such as giving more weight to wells close to the river and adding more drainage dynamics to the model input.

Background: Takayasu arteritis (TA) is a large vessel vasculitis that may complicate with cerebrovascular ischemic events. The objective was to describe clinical and vascular features of TA patients with cerebrovascular ischemic events and to identify risk factors for these events. Methods: We analyzed the prevalence and type of stroke/transient ischemic attack (TIA), factors associated with cerebrovascular ischemic events, and stroke-free survival in a large cohort fulfilling the American College of Rheumatology or Ishikawa criteria of TA. Results: Among 320 patients with TA (median age at diagnosis, 36 [25–47] years; 261 [86%] women), 63 (20%) had a stroke (n=41; 65%) or TIA (n=22; 35%). Ischemic event localized in the carotid territory for 55 (87%) patients and the vertebral artery territory in 8 (13%) patients. Multiple stenosis were observed in 33 (52%) patients with a median number of stenosis of 2 (minimum, 0 to maximum, 11), and aneurysms were observed in 10 (16%) patients. A history of stroke or TIA before TA diagnosis (hazard ratio [HR], 4.50 [2.45–8.17]; P P =0.05), myocardial infarction history (HR, 0.21 [0.05–0.89]; P =0.039), thoracic aorta involvement (HR, 2.05 [1.30–3.75]; P =0.023), time from first symptoms to diagnosis >1 year (HR, 2.22 [1.30–3.80]; P =0.005), and aspirin treatment (HR, 1.82 [1.04–3.19]; P =0.035) were associated with cerebrovascular ischemic event. In multivariate analysis, time from first symptoms to TA diagnosis >1 year (HR, 2.16 [1.27–3.70]; P =0.007) was independently associated with cerebrovascular ischemic events in patients with TA. The HR for cerebrovascular ischemic event in patients who already experienced a stroke/TIA was 5.11 (2.91–8.99; P Conclusions: Carotid stroke/TIA is frequent in TA. We identified factors associated with cerebrovascular ischemic events.

Antiplatelet therapy is one of the mainstays for secondary stroke prevention. This narrative review aimed to highlight the current evidence and recommendations of antiplatelet therapy for stroke prevention.We conducted advanced literature search for antiplatelet therapy. Landmark studies and randomised controlled trials evaluating antiplatelet therapy for secondary stroke prevention are reviewed. Results from Cochrane systematic review, pooled data analysis and meta-analysis are discussed.Single-antiplatelet therapy (SAPT) with aspirin, aspirin/extended-release dipyridamole or clopidogrel reduces the risk of recurrent ischaemic stroke in patients with non-cardioembolic ischaemic stroke or transient ischaemic attack (TIA). Dual-antiplatelet therapy (DAPT) with aspirin and clopidogrel or ticagrelor for 21–30 days is more effective than SAPT in patients with minor acute noncardioembolic ischaemic stroke or high-risk TIA. Prolonged use of DAPT is associated with higher risk of haemorrhage without reduction in stroke recurrence than SAPT. Compared with placebo, aspirin reduces the relative risk of recurrent stroke by approximately 22%. Aspirin/dipyridamole and cilostazol are superior to aspirin but associated with significant side effects. Cilostazol or ticagrelor might be more effective than aspirin or clopidogrel in patients with intracranial stenosis.SAPT is indicated for secondary stroke prevention in patients with non-cardioembolic ischaemic stroke or TIA. DAPT with aspirin and clopidogrel or ticagrelor for 21–30 days followed by SAPT is recommended for patients with minor acute noncardioembolic stroke or high-risk TIA. Selection of appropriate antiplatelet therapy should also be based on compliance, drug tolerance or resistance.

Supplemental Digital Content is available in the text., Background and Purpose: Women have worse outcomes than men after stroke. Differences in presentation may lead to misdiagnosis and, in part, explain these disparities. We investigated whether there are sex differences in clinical presentation of acute stroke or transient ischemic attack. Methods: We conducted a systematic review and meta-analysis according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Inclusion criteria were (1) cohort, cross-sectional, case-control, or randomized controlled trial design; (2) admission for (suspicion of) ischemic or hemorrhagic stroke or transient ischemic attack; and (3) comparisons possible between sexes in ≥1 nonfocal or focal acute stroke symptom(s). A random-effects model was used for our analyses. We performed sensitivity and subanalyses to help explain heterogeneity and used the Newcastle-Ottawa Scale to assess bias. Results: We included 60 studies (n=582 844; 50% women). In women, headache (pooled odds ratio [OR], 1.24 [95% CI, 1.11–1.39]; I2=75.2%; 30 studies) occurred more frequently than in men with any type of stroke, as well as changes in consciousness/mental status (OR, 1.38 [95% CI, 1.19–1.61]; I2=95.0%; 17 studies) and coma/stupor (OR, 1.39 [95% CI, 1.25–1.55]; I2=27.0%; 13 studies). Aspecific or other neurological symptoms (nonrotatory dizziness and non-neurological symptoms) occurred less frequently in women (OR, 0.96 [95% CI, 0.94–0.97]; I2=0.1%; 5 studies). Overall, the presence of focal symptoms was not associated with sex (pooled OR, 1.03) although dysarthria (OR, 1.14 [95% CI, 1.04–1.24]; I2=48.6%; 11 studies) and vertigo (OR, 1.23 [95% CI, 1.13–1.34]; I2=44.0%; 8 studies) occurred more frequently, whereas symptoms of paresis/hemiparesis (OR, 0.73 [95% CI, 0.54–0.97]; I2=72.6%; 7 studies) and focal visual disturbances (OR, 0.83 [95% CI, 0.70–0.99]; I2=62.8%; 16 studies) occurred less frequently in women compared with men with any type of stroke. Most studies contained possible sources of bias. Conclusions: There may be substantive differences in nonfocal and focal stroke symptoms between men and women presenting with acute stroke or transient ischemic attack, but sufficiently high-quality studies are lacking. More studies are needed to address this because sex differences in presentation may lead to misdiagnosis and undertreatment.

Ephemeral pans are transient natural habitats with harsh conditions found in semi-arid regions. These pans endure high evaporation rates, extreme temperatures and an overflow of water. Pans are characterised by dry land becoming submerged in water temporarily (flood-like) followed by a prolonged period absent of water (drought-like). Ephemeral pans are unique habitats that are essentially transient habitats from a freshwater system to increased salinity and eventually a dry landscape. Biodiversity associated with these pans must adapt to the transient environmental conditions. Unique adaptations of the biota for these habitats allow them to withstand extreme conditions. The objective of this study was to (1) identify changes in the water quality over time in the pans, to (2) identify succession of macro-invertebrates and (3) identify the water quality parameters of pans as drivers of macro-invertebrate assemblages. A total of five pans were measured in the Northern Cape province of South Africa located on the Savanna and Nama-Karoo biomes within a 4500 ha area. The measurements taken included water quality variables (pH, salinity, total dissolved solids [TDS]), taxon diversity and richness of macro-invertebrates and aquatic birdlife. Evaporation rate between the pans varied with time. There was a difference in the macro-invertebrate taxon richness between the pans. Macro-invertebrate taxon succession was observed over time and some macro-invertebrates showed confinement to pans of a particular biome. It was found that pH was significantly the most contributing factor to the taxon richness and diversity of the macro-invertebrates recorded, while the salinity and TDS increased with time as water evaporated. CONSERVATION IMPLICATIONS: The shrimps (fairy, clam and tadpole) were unique to the Nama-Karoo pans. It was found that pH (p < 0.05) was the most contributing factor to the taxon richness and diversity of the macro-invertebrates recorded, and salinity and TDS increased with time as water evaporated

Reliable transient thermal analysis plays a very important role in the engine safety analysis. Transient conjugate heat transfer simulation is an important way of temperature analysis. But there exists a great disparity in the time scales between solid conduction and fluid convection. The calculation cost of transient conjugate heat transfer analysis is very huge because of the tiny time step of computational fluid dynamics. The Bi-Fo time scaling method is proposed to improve the computational efficiency of transient conjugate heat transfer. On the one hand, this method carries out a similar transformation on solid heat conduction, scaling the calculation time with the product of density and specific heat capacity to maintain the consistency of Fourier number. On the other hand, it takes very short time for the fluid domain to recover stability after a boundary disturbance. Based on the above characteristic, the flow time is directly compressed to the same as that of the solid domain. It is verified by Mark Ⅱ vane that increasing the solid thermal diffusivity can reduce the time scale of heat conduction. In the situation of rapidly stable flow field, scaling flow time does not affect the solid thermal boundary under corresponding dimensionless time. Within the application scope, the Bi-Fo time scaling method can greatly reduce the time cost of transient conjugate heat transfer simulation while maintaining the accuracy of transient temperature analysis.

The present problem addressed the transient behavior of convective heat and mass transfer characteristics across a curved surface under the influence of exothermic catalytic chemical reactions. The governing non-linear mathematical model wastransformed into a convenient form with the help of a primitive variable formulation. The final primitive formed model wassolved numerically by applying the finite difference method. The analysis of the above said computed numerical data in terms of oscillatory heat transfer, skin friction, and oscillatory mass transfer for various emerging parameters, such as the mixed convection parameter λT, modified mixed convection parameter λc, index parameter n, activation energy parameter E, exothermicparameter β, temperature relative parameter γ, chemical reaction parameter λ, and Schmidt number Sc is plotted in graphical form. An excellent agreement is depicted for oscillatory heat transfer behavior at the large value of activation energy E. The amplitude of heat transfer and prominent fluctuating response in mass transfer with a certain height is found at each value of the index parameter n with a good alteration. An increase in the activation energy led to an increase in the surface temperature, which yielded more transient heat transfer in the above-said mechanism. The main novelty of the current study is that first, we ensured the numerical results for the steady state heat and fluid flow and then these obtained results wereused in the unsteady part to obtain numerical results for the transient behavior of the heat and mass transfer mechanism.

Objective: The common causes of central diabetes insipidus (CDI) include trauma to the pituitary, hypoperfusion, and malignancy. However, CDI can also be transient. An emerging cause of transient diabetes insipidus is through the use and withdrawal of vasopressin. Here, we present a case of transient CDI that developed during an intensive care unit admission. Case report: A Caucasian woman presented to the emergency room after a fall. On presentation, the patient was found to be in shock and was admitted to the surgical intensive care unit. Treatment with norepinephrine, vasopressin, and intravenous antibiotics was started. On day 5 of hospitalization, the patient’s blood pressure improved, and treatment with vasopressin was discontinued. On day 6 of hospitalization, the patient’s urine output increased and serum sodium level was elevated. Despite increasing free water, serum sodium level continued to rise. Endocrinology division was consulted, and urine osmolality was consistent with diabetes insipidus (DI). Urine osmolality at 30 and 60 minutes after desmopressin (1-desamino-8-d-arginine vasopressin [DDAVP]) was consistent with CDI. Magnetic resonance imaging scan of the brain showed no intracranial pathology. Over the next day with scheduled DDAVP, serum sodium level decreased below the goal level. Thus, DDAVP was held. Prior to discharge, the patient did not require additional DDAVP. She was discharged without DDAVP. Discussion: Our patient’s workup was initially consistent with CDI. However, the DI resolved spontaneously, supporting transient CDI secondary to vasopressin infusion. Different theories have emerged about why this occurs with vasopressin. However, further investigation is needed. Conclusion: Although rare, it is important to monitor for DI after vasopressin infusion and have a suspicion that DI may be transient in the absence of a clear cause.

Context:Chaos Engineering is an approach for investigating the resilience of software systems, i.e. their ability to withstand unexpected events, adapt accordingly, and continue providing functionality. An integral part of the approach is continuous experimentation, expressed in continuously executing so-called Chaos Experiments. A Chaos Experiment consists of two crucial elements, namely a steady-state hypothesis and an anomaly injection. Traditionally, during the experimentation process, the steady-state hypothesis is verified at the start of an experiment, after which the anomaly is injected, followed by a second evaluation of the steady-state hypothesis. This chaos experimentation process is well suited for identifying whether a system is in a steady-state after a failure is introduced. Problem:When applied, the traditional chaos experimentation approach can only verify whether the system is in a steady-state without providing any information about the time between the state changes, e.g. the recovery of the system. The experimentation process does not explicitly allow the specification of hypotheses regarding the transient behavior, i.e. the behaviors experienced during the transition between steady-states after a failure has been introduced. As a result, the experimentation process also does not support explicit verification of requirements on the transient behavior during the experiment, e.g, whether the response time stays below a given threshold all the time or whether a circuit breaker opens within a given time. Knowledge about such transient behaviors is beneficial for the stakeholders of the system. For example, assuming that high availability is of utmost importance for the business model of an application, a long period of recovery during which the application is unavailable after an unexpected failure could lead to considerable losses for various stakeholders. Objective:The first objective of the thesis is to examine how a transient behavior requirement can be specified in the context of Chaos Engineering and Chaos Experiments. The next goal of the thesis is to study how the Chaos Experimentation process can include a verification of transient behavior requirements. A further goal is to create a concept for an extended Chaos Engineering approach, which supports the specification of transient behavior hypotheses and their verification, and to implement the concept into a working prototype. After the prototype is developed, the last objective of the thesis is to evaluate the extended Chaos Engineering approach and its implementation. Method: In order to achieve the first objective of the thesis, formalisms capable of describing transient behaviors are examined with regard to their integration into Chaos Experiments. To accomplish the second objective, state-of-the-art Chaos Engineering tools are studied, and additionally, three expert interviews are conducted in order to elicit the requirements for such an extension of the Chaos Engineering approach. To accomplish the goal of creating a concept for the approach, the research results from the previous goals and the requirements elicited during the interviews are combined into a concept which is then implemented into a prototype. To reach the last goal of the thesis, the approach and the prototype are examined in three separate types of evaluation. Result: First, the results of the thesis include the requirements for an extended Chaos Engineering approach, supporting the specification and verification of transient behavior requirements. Furthermore, the results also include a concept for the realization of the extension. Moreover, the results also comprise a functioning prototype of the proposed approach and its evaluation. Conclusion:The proposed extension of the Chaos Engineering approach allows a deeper and more precise analysis of the resilience of software systems by enabling the specification and evaluation of more detailed and strict resilience requirements including transient behavior specifications. Furthermore, various stakeholders such as customers, operators, and developers benefit from the extended approach, allowing them to have stricter guarantees regarding the resilience of the application. Moreover, the prototype implementing the extended approach allows software engineers to easily adopt it and possibly extend it.

Uranium nitrides play important roles in dinitrogen activation and functionalization and in chemistry for nuclear fuels, but the synthesis and isolation of the highly reactive uranium(VI) nitrides remains challenging. Here, we report an example of transition metal (TM) stabilized U(VI) nitride complexes, which are generated by the photolysis of azide-bridged U(IV)-TM (TM = Rh, Ir) precursors. The U(V) nitride intermediates with bridged azide ligands are isolated successfully by careful control of the irradiation time, suggesting that the photolysis of azide-bridged U(IV)-TM precursors is a stepwise process. The presence of two U(VI) nitrides stabilized by three TMs is clearly demonstrated by an X-ray crystallographic study. These TM stabilized U(V) nitride intermediates and U(VI) nitride products exhibit excellent stability both in the solid-state and in THF solution under ambient light. Density functional theory calculations show that the photolysis necessary to break the N-N bond of the azide ligands implies excitation from uranium f-orbital to the lowest unoccupied molecular orbital (LUMO), as suggested by the strong antibonding N-(N2) character present in the latter.

The transient capability of a SP3 based pin-wise core analysis code SPHINCS is developed and verified through the analyses of the C5G7-TD benchmark. Spatial discretization is done by the fine mesh finite difference method (FDM) within the framework of the coarse mesh finite difference (CMFD) formulation. Pin size fine meshes are used in the radial fine mesh kernels. The time derivatives of the odd moments in the time-dependent SP3 equations are neglected. The pin homogenized group constants and Super Homogenization (SPH) factors generated from the 2D single assembly calculations at the unrodded and rodded conditions are used in the transient calculations via proper interpolation involving the approximate flux weighting method for the cases that involve control rod movement. The simplifications and approximations introduced in SPHINCS are assessed and verified by solving all the problems of C5G7-TD and then by comparing with the results of the direct whole core calculation code nTRACER. It is demonstrated that SPHINCS yields accurate solutions in the transient behaviors of core power and reactivity.

Line-start permanent-magnet synchronous motors (LSPMSMs) have poorer starting performance than induction motors. Optimization focusing only on transient performance improvement of the LSPMSM may degrade steady-state performance, and vice versa. In fact, an optimization focusing on maximizing starting torque may reduce efficiency by up to approximately 7% and optimizing efficiency may cause degradation in starting torque by 5%. Hence, simultaneous steady-state and transient performance optimization of a 4-kW LSPMSM under a multi-objective function is examined in this study. Efficiency maximization and starting torque maximization are nominated as objective functions. Two different optimization approaches, a gradient-based algorithm and gradient-free algorithm, are employed to optimize the LSPMSM. Sequential nonlinear programming is used as the gradient-based algorithm in this study, and the gradient-free algorithm used is the genetic algorithm (GA). A comparative study of the algorithms’ performance is presented. To provide an inclusive comparison of both algorithms’ performance, a similar optimization study is implemented for a baseline induction motor. The results demonstrate that the multi-objective optimization improves steady-state and start-up performance of both motors. Results indicate that both algorithms converge reliably to almost the same optimum (objective) value. Depending on the nature of the optimization problem, number of design variables, and degree of convergence, the genetic algorithm requires many more evaluations than the gradient-based algorithm. Accordingly, optimization time required by the GA is more than the gradient-based algorithm under similar conditions. Refereed/Peer-reviewed

This study discusses the determination of the stabilized flow coefficient, C, in the Rawlins and Schellhardt equation. It is applicable in the reservoir with low porosity and permeability model, usually found in unconventional reservoirs. In determining the flow coefficient, a deliverability test method proposed by Hashem and Kazemi was used during the transient flow period of a gas well. Besides, in determining the deliverability exponent, n, used in the least squared analysis equation derived by Johnston and Lee in the determination of C stabilized so that from each value of n, there will be supporting data for determining stabilized flow coefficient. Finally, the application and previous method will determine the flow coefficient value based on reservoir model time stabilization. Later it compares with the John Lee equation and IPR constructs from the model and John Lee.

Author(s): Jabola, Raymond; Boswell, Benjamin; Lutz, Robert H.; Casey, Jack; Ceraulo, Anthony | Abstract: Introduction: Spinal cord injuries are a common reason for presentation to the emergency department (ED). Sports-related spinal injuries are one of the least common spinal injuries, falling behind vehicular accidents, acts of violence, and falls.Case Report: This case report describes a case of transient quadriplegia in a 17-year-old male who presented to the ED after a helmet-to-helmet collision while participating in football.Conclusion: Emergency physicians should be cognizant of potential spinal cord injury using clinical decision tools and radiologic imaging to properly disposition a patient presenting with cervical spine injury.

Introduction Recent trials report positive results for preventing vascular events with dual antiplatelet therapy (DAPT) in patients with high-risk TIA or minor ischemic stroke. We aimed to investigate this population regarding influence of age on vascular risk factors, hospital stay and mortality. Patients and methods Data on patients aged 40–100 years with TIA or ischemic stroke in the Swedish Stroke Register during 2012–13 were linked with national registers. To identify patients with high-risk TIA (ABCD2 ≥6) or minor ischemic stroke (NIHSS ≤5) eligible for DAPT, we excluded patients with atrial fibrillation, anticoagulant use, prior major bleeding, or unknown stroke severity. Findings We identified 10,053 potential DAPT-candidates (mean age 72.6 years, 45.2% female, 16.4% with TIA). With advancing age, most vascular risk factors increased. Antiplatelet treatment increased from 31.9% before the event to 95.5% after discharge. Within 1 year following index event, the proportion of patients with ≥1 re-admission increased with age (29.2% in 40–64 year-olds; 47.2% in 85–100 year-olds). All-cause death per 100 person-years was 6.9 (95% CI 6.4–7.4) within 1 year, and highest in the first 30 days (15.2; 95% CI 12.8–18.2). For each year of increased age, the risk of death increased with 3.5% (p = 0.128) in patients 40–64 years and with 11.8% (p Conclusions While in theory representing a subset of patients with mild injury, our observational study highlights substantial use of health-care resources and high mortality rates among patients with high-risk TIA or minor ischemic stroke assumed eligible for DAPT.

Context The apparent increased incidence of congenital hypothyroidism (CH) is partly due to increased detection of transient disease. Objective This work aims to identify predictors of transient CH (T-CH) and establish a predictive tool for its earlier differentiation from permanent CH (P-CH). Methods A retrospective cohort study was conducted of patients diagnosed with CH from 2006 to 2015 through Newborn Screening Ontario (NSO). Results Of 469 cases, 360 (76.8%) were diagnosed with P-CH vs 109 (23.2%) with T-CH. Doses of levothyroxine predicting T-CH were less than 3.9 μg/kg at age 6 months, less than 3.0 μg/kg at ages 1 and 2 years, and less than 2.5 μg/kg at age 3 years. Descriptive statistics and multivariable logistic modeling demonstrated several diverging key measures between patients with T-CH vs P-CH, with optimal stratification at age 1 year. Thyroid imaging was the strongest predictor (P Conclusion A levothyroxine dose of less than 3 μg/kg at ages 1 and 2 years and less than 2.5 μg/kg at age 3 years can be predictive of T-CH. A novel risk score was developed that can be clinically applied to predict the likelihood of a successful trial off therapy for a given patient at age 1 year.

The differential outcomes across the age spectrum of transcatheter aortic valve implantation (TAVI) recipients are still debated. Aim of the study was to evaluate the clinical outcomes of oldest-old patients undergoing TAVI in the large "Registro Italiano GISE sull'impianto di Valvola Aortica Percutanea (RISPEVA)" registry. A total of 3,507 patients were stratified according to age: 1,381 were ≥85 years, 2,126 were85 years. Primary endpoints were death at 30-days and complete follow-up (FU) (medium 368 days). Cerebrovascular events, myocardial infarction, bleedings, vascular complications at 30-days and complete FU were considered. In the unadjusted analysis, 30-days mortality in the oldest-old group was higher than in younger patients (4.2% vs 2.4%; p = 0.007); this difference kept true also at complete FU (19.6% vs 15.9%; p = 0.014). After propensity score (PS) matching, the oldest-old population showed a higher mortality solely at 30-days (4.7% vs 2.4%; p = 0.016), while the survival at complete FU was similar to that of younger patients (20.1% vs 18.0%; p = 0.286). The incidence of non-fatal outcomes resulted comparable between the 2 groups, also after propensity score matching. At the multivariate logistic regression analysis procedural major or disabling bleedings, cerebrovascular events, cardiogenic shock resulted predictors of 30-days death in the oldest-old cohort. In conclusion, patients ≥85 years can safely undergo TAVI being not more exposed to procedural complications than those85 years; nevertheless they showed worse 30-days mortality, probably driven by reduced tolerance to complications. Passed the critical periprocedural phase, patients ≥85 years had a similar survival to those85 years with comparable risk profile.

The brake system of an automobile is composed of disc brake and pad which are co-working components in braking and accelerating. In the braking period, due to friction between the surface of the disc and pad, the thermal heat is generated. It should be avoided to reach elevated temperatures in disc and pad. It is focused on different disc materials that are gray cast iron and carbon ceramics, whereas pad is made up of a composite material. In this study, the CFD model of the brake system is analyzed to get a realistic approach in the amount of transferred heat. The amount of produced heat can be affected by some parameters such as velocity and friction coefficient. The results show that surface temperature for carbon-ceramic disc material can change between 290 and 650 K according to the friction coefficient and velocity in transient mode. Also, if the disc material gray cast iron is selected, it can change between 295 and 500 K. It is claimed that the amount of dissipated heat depends on the different heat transfer coefficient of gray cast iron and carbon ceramics.

We study the interaction of solar wind protons with Earth's quasi-parallel bow shock using a hybrid-Vlasov simulation. We employ the global hybrid model Vlasiator to include effects due to bow shock curvature, tenuous upstream populations, and foreshock waves. We investigate the uncertainty of the position of the quasi-parallel bow shock as a function of several plasma properties and find that regions of non-locality or uncertainty of the shock position form and propagate away from the shock nose. Our results support the notion of upstream structures causing the patchwork reconstruction of the quasi-parallel shock front in a non-uniform manner. We propose a novel method for spacecraft data to be used to analyse this quasi-parallel reformation. We combine our hybrid-Vlasov results with test-particle studies and show that proton energization, which is required for injection, takes place throughout a larger shock transition zone. The energization of particles is found regardless of the instantaneous non-locality of the shock front, in agreement with it taking place over a larger region. Distortion of magnetic fields in front of and at the shock is shown to have a significant effect on proton injection. We additionally show that the density of suprathermal reflected particles upstream of the shock may not be a useful metric for the probability of injection at the shock, as foreshock dynamics and particle trapping appear to have a significant effect on energetic-particle accumulation at a given position in space. Our results have implications for statistical and spacecraft studies of the shock injection problem.

Background: Moyamoya syndrome, a progressive, idiopathic stenosis of the internal carotid arteries, results in increased risk for both ischemic and hemorrhagic strokes. Revascularization procedures have been shown in small studies to be both safe and efficacious for these patients; however, randomized controlled trials are lacking. The goal of this systematic review is to organize the literature evaluating surgical intervention versus conservative medical management. Methods: A systematic review was performed including studies with 3 or more participants with moyamoya syndrome in the setting of sickle cell disease and a measured outcome after either medical or surgical intervention. Relevant studies were identified using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria and a set of predetermined key words. Results: Sixty-one articles were identified with 6 articles ultimately included in this review (N = 122). Of the patients, 73 (59.8%) were revascularized surgically (all indirect procedures), whereas 49 (40.2%) remained on chronic transfusion therapy. Of the patients that underwent indirect revascularization surgery, a total of 1 perioperative (1.4%) and 4 postoperative strokes (5.5%) were reported over 44 months (1 stroke per 53.3 patient-years). In comparison, an average of 46.5% of patients who were receiving chronic transfusions had major events (stroke or transient ischemic attack) while undergoing therapy (1 stroke per 13.65 patient-years, P = 0.00215). Conclusions: We present a large systematic review of the literature regarding outcomes of surgical and medical management for patients with moyamoya syndrome and sickle cell disease. The findings redemonstrate the efficacy and safety of surgical revascularization, and advocate for earlier discussion around surgical intervention. © 2019 Elsevier Inc.

This article examines the influence of isothermal and isoflux heating/cooling with heat source/sink on unsteady hydromagnetic-free convective flow of a viscous incompressible fluid in an annulus. The flow is induced by buoyancy forces due to temperature differences as a result of the isothermal heating and constant heat flux applied on the outer surface of the inner cylinder. Our treatment of the governing energy and momentum equation is based on a two-step approach. First, the nonlinear partial differential equations are transformed to the Laplace domain using the Laplace transform method and solved analytically in the Laplace domain. The Laplace domain solution is then inverted back to time domain using a numerical scheme known as Riemann-Sum Approximation (RSA). The derived numerical values by the method of RSA exhibit an excellent conformity with PDEPE and steady-state solutions at large time. The influence of the various dimensionless controlling parameters on the flow formation is depicted graphically and in tabular form.

The pressure damping occurring in pressurized pipes with a leak during transients has been examined as a diagnostic tool – the so-called transient damping method (TDM) – mainly from the theoretical and numerical point of view. On the contrary, the experimental data are limited to few cases. As a consequence, there is a need of an extensive experimental analysis of the role played on the pressure damping by leak parameters (size, location and initial pressure). On the basis of the laboratory tests executed on a polymeric pipe, it is shown that, while the magnitude of the injected pressure wave does not affect the damping, the initial pressure, the leak size and location influence it plainly. Moreover, an experimental evidence is provided of the ambiguity in the time-domain of the transient pressure damping pointed out by numerical experiments. Precisely, it is demonstrated that different combinations of the leak parameters can lead to the same pressure damping. The obtained results indicate that the TDM can give a reliable assessment of the pipe status only if it is integrated with other diagnostic tools, such as the interpretation of the pressure signal during the first characteristic time of the pipe.

Supramolecular gels can be designed such that pre-determined changes in state occur. For example, systems that go from a solution (sol) state to a gel state and then back to a sol state can be prepared using chemical processes to control the onset and duration of each change of state. Based on this, more complex systems such as gel-to-sol-to-gel and gel-to-gel-to-gel systems can be designed. Here, we show that we can provide additional insights into such systems by using rheological measurements at varying values of frequency or strain during the evolution of the systems. Since the different states are affected to different degrees by the frequency and/or strain applied, this allows us to better understand and follow the changes in state in such systems.

Flexible alternating current transmission system (FACTS) devices are deployed for improving power system’s stability either singly or as a combination. This research investigates hybrid FACTS devices and studies their impact on voltage, small-signal and transient stability simultaneously under various system disturbances. The simulations were done using five FACTS devices-static var compensator (SVC), static synchronous compensator (STATCOM), static synchronous series compensators (SSSC), thyristor controlled series compensator (TCSC) and unified power flow controller (UPFC) in MATLAB’s power system analysis toolbox (PSAT). These five devices were grouped into ten pairs and tested on Kenya’s transmission network under specific contingencies: the loss of a major generating machine and/or transmission line. The UPFC-STATCOM pair performed the best in all the three aspects under study. The settling times were 3 seconds and 3.05 seconds respectively for voltage and rotor angle improvement on the loss of a major generator at normal operation. The same pair gave settling times of 2.11 seconds and 3.12 seconds for voltage and rotor angle stability improvement respectively on the loss of a major transmission line at 140% system loading. From the study, two novel techniques were developed: A performance-based ranking system and classification for FACTS devices.

ASELSAN Inc. has been working on electromagnetic launch technologies since 2014. The first prototype, EMFY-1, has a 25 mm x 25 mm square bore and 3-m-length rails. The second prototype, EMFY-2, has a 50 x 50 mm square bore and 3-m-length. This article presents a recently developed prototype, EMFY-3, with a 50 x 75 mm rectangular bore and 6-m length. The input energy of the pulsed-power supply (PPS) is doubled to 8 MJ, and the 2.91 MJ muzzle energy is obtained. Velocity curves are captured with Doppler radar, enabling us to establish propulsive inductance gradient $L{'}_{{pr}}$ transients empirically. The results confirm that $L{'}_{{pr}}$ is constant throughout the launch, as no significant breaking mechanism occurs with the non-magnetic containment. However, a slight variation (2% at maximum) happens with different rails' current magnitudes from one launch to another. The transition phenomenon is a candidate for the drop in the $L{'}_{{pr}}$ , as it occurs more likely at launches with higher linear current densities. Moreover, a sensitivity analysis is conducted to show the importance of $L{'}_{{pr}}$ calculations. A deviation of 5% from the actual value can cause an error in muzzle velocity up to 6.2%. This fact indicates that simulation models are very susceptible to $L{'}_{{pr}}$ calculations. Although $L{'}_{{pr}}$ is calculated as 0.515 mu H/m with 3-D finite element method (FEM), the Kerrisk formula calculates as if 0.561 mu H/m; the experimental measurement gives 0.575 mu H/m. These methods differ by 8% at maximum, which causes muzzle velocities errors. Regarding empirical findings, the 3-D FEM model calculates $L{'}_{{pr}}$ more precisely than analytical formulas, and the contrast between models have grave importance due to the muzzle velocity errors.

In order to improve the understanding of the phenomena underlying the boiling occurrence, CEA Cadarache (France) is designing a new experimental setup, intended to operate for pressures ranging from atmospheric to PWR conditions. This will allow optical access to the convective boiling flow as well as thermal imaging (infrared thermography) of the heated surface. A two-step methodology for designing the heater (particularly its thickness since it directly influences the boiling mechanisms) was developed. This approach is based on solving the heat conduction problem within the heater, considering realistic time-dependent boundary conditions representative of the boiling process. Since those boundary conditions are measured on the external face of the heater, this heat transfer problem is known as an inverse problem that is difficult to solve because of its ill-posedness and high sensitivity to boundary condition uncertainties. In the first stage, we considered one-dimensional modeling to determine the order of magnitude of the heater’s thickness that guaranteed a correct reconstruction of the wet temperature from the measured dry temperature in terms of uncertainties. This value was confirmed in the second stage using a two-dimensional model that accounted for the presence of multiple bubbles on the wet side.

The two-dimensional transient heat conduction through a multilayers wall made of different materials and thicknesses was numerically resolved. The equations system resolution was carried out by Alternating direction implicit method (ADI). The outdoor and indoor temperatures and the convective coefficients used as boundary conditions in the developed Fortran program were from the Algerian regulatory technical document. After validation of the Fortran program with literature, it was used to studying the influence of different boundary conditions (bottom and top sides), on the thermal insulation in the building, for many configurations of external walls, usually used in building construction at Batna city (Algeria). Results showed that for the configurations that give bad thermal insulation, the conditions imposed on the top and bottom of the wall have practically no influence on the internal temperature of the multilayers wall, however, the opposite is observed for the configurations that ensure good thermal insulation.

Objectives. Given the high prevalence of subclinical hypothyroidism (SCH), defined as high thyroid stimulating hormone (TSH) and normal free thyroxine (FT4), and uncertainty on treatment, one of the major challenges in clinical practice is whether to initiate the treatment for SCH or to keep the patients under surveillance. There is no published study that has identified predictors of short-term changes in thyroid status amongst patients with mild elevation of TSH (4.5–10 mIU/L). Subjects and Results. A cohort study was conducted on patients with SCH detected through a general population screening program, who were followed for six months. This project identified factors predicting progression to hypothyroid status, persistent SCH and transient cases. A total of 656 participants joined the study (431 controls and 225 were patients with SCH). A part of participants (12.2%) developed biochemical hypothyroidism during the follow-up, while 73.8% of the subjects became euthyroid and the remained ones (13.4%) stayed in the SCH status. The incidence of overt hypothyroidism for participants with TSH above 6.9 mIU/L was 36.7%, with incidence of 42.3% for females. Anti-thyroid peroxidase antibodies (TPO) positivity is an important predictor of development of hypothyroidism; however, it could be also positive due to transient thyroiditis. Conclusions. It can be concluded that females with TSH above 6.9 mIU/L, particularly those with free triiodothyronine (FT3) and FT4 in the lower half of the reference range, are more likely to develop biochemical hypothyroidism. Therefore, it is recommended to give them a trial of levothyroxine replacement. It is also recommended to repeat TSH after six months for male subjects and participants with baseline TSH equal or less than 6.9 mIU/L.

Ornithine transcarbamylase (OTC) deficiency is an incredibly rare disease in the subgroup of urea cycle disorders. Although typically seen in the neonate shortly after initiating high protein feeds (human breastmilk or infant formula), patients with partial/heterozygous deficiencies can often be diagnosed later in life with unique sequelae. One such manifestation is sudden, transient vision loss shortly after an initial episode of hyperammonemia in a patient without a known diagnosis of OTC deficiency. Only two such occurrences are documented in academic literature and both share many similar presenting features hinting that a hidden, but the consistent pathophysiologic mechanism of this disease is at play. Scarce research is available to propose a concise explanation; however, recent advancements in the literature point toward the brain’s inability to uptake glucose and convert it into glutamate in patients with partial OTC deficiency as a likely explanation.

Cardiogenic pulmonary edema complicated by transient left bundle branch block (LBBB) is a relatively rare finding. We report a case of a 52-year-old woman with underlying heart failure but no structural heart disease who was referred for evaluation due to severe shortness of breath and documented LBBB on a 12-lead EKG. She was diagnosed with cardiogenic pulmonary edema due to medication noncompliance. With the resolution of her symptoms by treating her pulmonary edema with bisoprolol and furosemide, repeated EKG showed resolution of LBBB. A review of her medical records showed similar presentations of pulmonary edema associated with transient LBBB. In conclusion, to the best of our knowledge, transient LBBB associated with cardiogenic pulmonary edema is very uncommon. The etiology of transient LBBB remains unclear, however, the most likely theory that explains our patient’s transient LBBB is a consequence of ventricular enlargement from fluid overload and cardiac muscle strain with dilatation, causing bundle conduction interruption. Our patient’s cardiogenic pulmonary edema was complicated with transient LBBB in multiple previous presentations with a resolution of the LBBB after treating the underlying pulmonary edema.

Novel therapeutic strategies aiming at the permanent inactivation of the HIV-1 reservoir in infected individuals are currently being explored, including approaches based on CRISPR-Cas gene editing. Extinction of all infectious HIV provirus in infected T-cell cultures was previously achieved when cells were transduced with lentiviral vectors for the stable expression of CRISPR-Cas9 or Cas12a systems targeting HIV DNA. Because lentiviral transduction and long-term CRISPR-Cas activity are less suitable for in vivo application of this antiviral strategy, we investigated whether HIV can also be completely inactivated by transient CRISPR-Cas activity. Latently infected SupT1 T-cells were repeatedly transfected with different Cas9 and Cas12a mRNA/protein sources in combination with dual gRNAs/crRNAs targeting highly conserved viral sequences. Upon repeated Cas9 protein treatment, viral replication could no longer be reactivated. We demonstrate that this was due to complete mutational inactivation of the proviral DNA, mostly through mutations at the target sites, but also through excision or inversion of the viral DNA fragment between the two target sites. These results demonstrate that repeated transient CRISPR-Cas treatment of a latently infected T-cell culture can lead to the permanent inactivation of HIV replication, indicating that transient CRISPR-Cas delivery methods can be considered for in vivo application.

Abstract Environmentally friendly degradable sensors with both hazardous gases and pressure efficient sensing capabilities are highly desired for various promising applications, including environmental pollution monitoring/prevention, wisdom medical, wearable smart devices, and artificial intelligence. However, the transient gas and pressure sensors based on only identical sensing material that concurrently meets the above detection needs have not been reported. Here, we present transient all-MXene NO2 and pressure sensors employing three-dimensional porous crumpled MXene spheres prepared by ultrasonic spray pyrolysis technology as the sensing layer, accompanied with water-soluble polyvinyl alcohol substrates embedded with patterned MXene electrodes. The gas sensor achieves a ppb-level of highly selective NO2 sensing, with a response of up to 12.11% at 5 ppm NO2 and a detection range of 50 ppb–5 ppm, while the pressure sensor has an extremely wide linear pressure detection range of 0.14–22.22 kPa and fast response time of 34 ms. In parallel, all-MXene NO2 and pressure sensors can be rapidly degraded in medical H2O2 within 6 h. This work provides a new avenue toward environmental monitoring, human physiological signal monitoring, and recyclable transient electronics.

An emerging area of interest within photovoltaic (PV) centred research is the simulation of the propagation of electromagnetic interference (EMI) and surges within PV installations. An overarching constraint in all simulation-based research is the accuracy of the models employed. In general, for PV-focussed simulations, nonlinear models are utilised for direct current (DC) analyses, whilst linearised models are employed for analyses involving surges or conducted electromagnetic interference. For large-signal electromagnetic interference and surges, the following two problems arise: (1) the aforementioned linearisation is only valid for the small-signal case, and (2) as they are constructed using only DC measurements, traditional large-signal PV models are generally only valid for DC conditions. Therefore, neither of these approaches can properly represent real-world PV behaviour under dynamic conditions. To overcome this limitation, this article proposes a more suitable model, compatible with Simulation Program with Integrated Circuit Emphasis (SPICE), and which results from the combination of two sub-models: one for large-signal DC cases, and one for small-signal alternating current (AC) cases. Consequently, the combined model enables improved modelling of the effects of large-signal transient perturbations to be performed, as well as cases involving small-signal AC and large-signal DC perturbations. The model parameters are extracted using data from two different classes of measurement setups: the first utilised a vector network analyser (VNA) to produce small-signal AC impedance results (covering a frequency range between 1 Hz and 50 MHz), and the second produces DC current-voltage curves. Both classes of measurement setup consider the device under test at multiple operating points. Key results include: (1) an improved SPICE-compatible PV model which caters for large-signal transient simulations, as well as for small-signal AC and large-signal DC cases, (2) improvements in the modelling of reverse bias behaviour when compared to the standard SPICE diode implementation, (3) the correct implementation of a voltage-dependent total capacitance (suitable for large-signal simulations), (4) modelling parameters for both a small (10 W) and a large (310 W) PV module, (5) measurement results which de-embedded the parasitic effects of the test setups employed, and (6) above 1 MHz, the physical layouts of the cells within the PV modules begin to influence the observed impedances.

We present an observational study of the luminous red nova (LRN) AT 2021biy in the nearby galaxy NGC 4631. The field of the object was routinely imaged during the pre-eruptive stage by synoptic surveys, but the transient was detected only at a few epochs from ∼231 days before maximum brightness. The LRN outburst was monitored with unprecedented cadence both photometrically and spectroscopically. AT 2021biy shows a short-duration blue peak, with a bolometric luminosity of ∼1.6 × 1041 erg s−1, followed by the longest plateau among LRNe to date, with a duration of 210 days. A late-time hump in the light curve was also observed, possibly produced by a shell-shell collision. AT 2021biy exhibits the typical spectral evolution of LRNe. Early-time spectra are characterised by a blue continuum and prominent H emission lines. Then, the continuum becomes redder, resembling that of a K-type star with a forest of metal absorption lines during the plateau phase. Finally, late-time spectra show a very red continuum (TBB ≈ 2050 K) with molecular features (e.g., TiO) resembling those of M-type stars. Spectropolarimetric analysis indicates that AT 2021biy has local dust properties similar to those of V838 Mon in the Milky Way Galaxy. Inspection of archival Hubble Space Telescope data taken on 2003 August 3 reveals a ∼20 M⊙ progenitor candidate with log (L/L⊙) = 5.0 dex and Teff = 5900 K at solar metallicity. The above luminosity and colour match those of a luminous yellow supergiant. Most likely, this source is a close binary, with a 17–24 M⊙ primary component.

The Advanced Multilevel Predictor-Corrector Quasi-static Method (AML-PCQM) is proposed in this work. The four computational levels, including transport, Multi-Group (MG) Coarse Mesh Finite Difference (CMFD), One-Group (1G) CMFD, and Exact Point-Kinetics Equation (EPKE), are coupled with a new dynamic iteration strategy. In each coupling algorithm, the original Transient Fixed Source Problem (TFSP) is solved in the predictor process using coarse time step, and then the flux distribution is factorized to the functions of amplitude and shape in the next corrector process. Finally, multiple fine time steps are used to adjust the predicted solution. Two heterogeneous single assembly problems with the prompt control rod withdrawal event are used to verify the AML-PCQM scheme’s accuracy and efficiency. The numerical results obtained by different cases are compared and analyzed. The final results indicate that the AML-PCQM performs the remarkable advantages of efficiency and accuracy with the reference cases.

Background Antiplatelet drugs may prevent recurrent ischemic events after ischemic stroke but their relative effectiveness and harms still need to be clarified. Within this network meta-analysis we aimed to summarize the current evidence for using antiplatelet drugs for secondary stroke prevention. Methods We searched MEDLINE, EMBASE and CENTRAL up to September 2020. Randomized controlled trials (RCTs) assessing antiplatelet drugs for secondary stroke prevention were included. We did pairwise meta-analyses and network meta-analyses using random-effects models. Primary outcomes were all strokes (ischemic or hemorrhagic) and all-cause mortality. Results The review included 57 RCTs, 50 (n = 165,533 participants) provided data for the meta-analyses. Compared to placebo/no treatment, moderate to high-confidence evidence indicated that cilostazol, clopidogrel, dipyridamole + aspirin, ticagrelor, ticlopidine, and aspirin ≤ 150 mg/day significantly reduced the risk of all strokes (odds ratios, ORs and absolute risk difference, ARD): cilostazol 0.51 (95 % confidence interval, CI, 0.37 to 0.71; 3.6 % fewer), clopidogrel 0.63 (95 % CI, 0.49 to 0.79; 2.7 % fewer), dipyridamole + aspirin 0.65 (95 % CI, 0.55 to 0.78; 2.5 % fewer), ticagrelor 0.68 (95 % CI, 0.50 to 0.93; 2.3 % fewer), ticlopidine 0.74 (95 % CI 0.59 to 0.93; 1.9 % fewer), aspirin ≤ 150 mg/day 0.79 (95 % CI, 0.66 to 0.95; 1.5 % fewer). Aspirin > 150 mg/day and the combinations clopidogrel/aspirin, ticagrelor/aspirin, also decrease all strokes but increase the risk of hemorrhagic events. Only aspirin > 150 mg/day significantly reduced all-cause mortality (OR 0.86, 95 % CI 0.76 to 0.97; ARD 0.9 %, 95 %CI 1.5–0.2 % fewer, moderate confidence). Compared to aspirin ≤ 150 mg/day, clopidogrel significantly reduced the risk of all strokes, cardiovascular events, and intracranial hemorrhage outcomes. Cilostazol also appeared to provide advantages but data are limited to the Asian population. Conclusions Considering the benefits and harms ratio, cilostazol, clopidogrel, dipyridamole + aspirin, ticagrelor, ticlopidine, and aspirin ≤ 150 mg/day appear to be the best choices as antiplatelet drugs for secondary prevention of patients with ischemic stroke or TIA. Systematic review registration PROSPERO CRD42020159896.

Development of a small district heating reactor was started at VTT Technical Research Centre of Finland. The concept features a 50 MW reactor that operates at low temperature and pressure. Traditional LWR technology, passive safety functions and natural circulation are combined in the integrated design. This paper presents the thermal-hydraulic design and transient analyses done with Apros simulation software. The studied cases include station blackout with reactor trip and as an ATWS scenario, and small break LOCA in the lower downcomer. During the station blackout transients, both temperature and pressure remained at safe levels. The innovative containment design functioned as planned and was capable of efficient decay heat removal. The small break LOCA ceased the natural circulation, but the core was not uncovered at any point and the core temperatures remained low. The results from the thermal-hydraulic analyses are promising and show that the reactor design is capable of producing low temperature heat to the district heating network. The analyzed transients posed no risk to reactor safety, and the passive containment function was capable of removing decay heat efficiently. These preliminary analyses give valuable insight to the design work in the future.

BackgroundPatients with intracranial atherosclerotic disease (ICAD) have a high frequency of stroke recurrence. However, there has been little investigation into the prognostic value of higher-resolution magnetic resonance imaging (HR-MRI).PurposeTo investigate the use of intracranial atherosclerotic plaques features in predicting risk of recurrent cerebrovascular ischemic events using HR-MRI.Study typeProspective.PopulationFifty-eight patients with acute/subacute stroke (N=46) or transient ischemic attack (N=12).Field strength/sequenceA 3.0 T, 3D time-of-flight gradient echo sequence and T1- and T2-weighted fast spin echo sequences with 0.31 x 0.39 mm2 in-plane resolution, twice (with >3 months between scans) following the initial event.AssessmentPatients were also followed clinically for recurrent ischemic events for up to 48 months or until a subsequent event occurred. The degree of stenosis, plaque burden (PB), minimal lumen area (MLA), and contrast enhancement ratio were assessed at each scanning session and the percentage change of each over time was calculated.Statistical testsUnivariable and multivariable Cox regression analyses were used to calculate the hazard ratio (HR) and 95% confidence interval (CI) for predicting recurrent events.ResultsThe mean time interval between baseline and follow-up MRI scans was 6.2 ± 4.1 months. After the second MRI scan, 20.7% of patients (N=12) had experienced ipsilateral recurrent TIA/stroke within 10.9 ± 9.2 months. Univariable analyses showed that baseline triglyceride, percentage change of PB, and progression of PB were significantly associated with recurrent events (all P

Objectives: The aim of the study was to determine the frequency and natural history of infantile idiopathic cholestasis (IC) in a large, prospective, multicenter cohort of infants. Methods: We studied 94 cholestatic infants enrolled up to 6 months of age in the NIDDK ChiLDReN (Childhood Liver Disease Research Network) “PROBE” protocol with a final diagnosis of IC; they were followed up to 30 months of age. Results: Male sex (66/94; 70%), preterm birth (22/90 with data; 24% born at < 37 weeks’ gestational age), and low birth weight (25/89; 28% born at 1 mg/dL and/or ALT > 35 U/L; n = 7), and exited healthy (resolved disease per study site report but without documented biochemical resolution; n = 34). Biochemical resolution occurred at median of 9 months of age. GGT was

There is a significant need for 3-D steady-state and transient neutron transport formulations and codes that yield accurate, high-fidelity solutions with reasonable computing resources and time. These tools are essential for modeling innovative nuclear systems, such as next-generation reactor designs. The existing methods generally compromise heavily between accuracy and affordability in terms of computation times. In this dissertation, novel algorithms for simulation of reactor transient conditions have been developed and implemented into the RAPID code system. In addition, extensive computational verification and experimental validation of RAPID's steady-state and transient algorithms was performed, and a novel virtual reality system (VRS) web-application was developed for the RAPID code system. The new algorithms, collectively referred to as tRAPID, are based on the Transient Fission Matrix (TFM) methodology. By decoupling the kinetic neutron transport problem into two different stages (an accurate pre-calculation to generate a database and an on-line solution of linear partial differential equations) the method ensures the preservation of the highest level of accuracy while also allowing for high-fidelity modeling and simulation of nuclear reactor kinetics in a short time with minimal computing resources. The tRAPID algorithms have been computationally verified using several computational benchmarks and experimentally validated using the JSI TRIGA Mark-II reactor. In order to develop these algorithms, first the steady-state capabilities of RAPID have been successfully benchmarked against the GBC-32 spent fuel cask system, also highlighting issues with the standard eigenvalue Monte Carlo calculations that our code is capable of overcoming. A novel methodology for accounting for the movement of control rods in the JSI TRIGA reactor has been developed. This methodology, referred to as FM-CRd, is capable of determining the neutron flux distribution changes due to the presence of control rod in real-time. The FM-CRd method has been validated with successfully using the JSI TRIGA reactor. The time-dependent, kinetic capabilities of the new tRAPID algorithm have been implemented based on the Transient Fission Matrix (TFM) method. tRAPID has been verified and validated using the Flattop-Pu benchmark and reference calculations and measurements using the JSI TRIGA reactor. In addition to the main tRAPID algorithms development and benchmarking efforts, a new web-application for the RAPID Code System for input preparation and interactive output visualization was developed. VRS-RAPID greatly enhances the usability, intuitiveness, and outreach possibilities of the RAPID Code System. Doctor of Philosophy The simulation of the behavior of nuclear systems (such as power reactors) relies on the development of innovative software that allows for calculating nuclear-relevant quantities in support of the design, operation, and safety of said systems. Traditional codes are often very complex and need to rely on approximations and/or require a very large amount of time to perform even a single calculation. The RAPID Code System is based on a methodology that allows for pre-calculation of a database that can later be used to simulate nuclear systems in real-time while achieving high levels of accuracy. For this dissertation, several new algorithms for simulation of equilibrium and transient conditions of nuclear systems have been developed for the RAPID Code System. In particular, the main features and additions are the ability of simulating the insertion of control rods (devices that are used to control the fission chain reaction) in nuclear reactors and the ability of analyzing the kinetics of nuclear systems. This latter feature, in particular, is extremely important and difficult to simulate, as it involves the fast variation in time of the nuclear quantities under analysis. Finally, a Virtual Reality System (VRS) is embedded with RAPID for easy utilization of the code through a web-application. All these new algorithms and tools have been benchmarked and validated, against reference high-fidelity computational predictions and experimental data. This dissertation demonstrates RAPID's ability of achieving accurate high quality solutions in a rather short time.

We describe an elderly woman who underwent a treadmill test preoperatively and was found to have Exercise-induced Left Bundle Branch Block without chest pain. Coronary angiogram was done which revealed a 70% stenosis in the fi rst diagonal branch of Left Anterior Descending Artery and a 40% lesion in proximal Right Coronary Artery. Available literature attributes rate-dependent transient conduction defects to obstructive lesions of coronary arteries, slow arterial blood fl ow, vasospasms as well as pathology in the Bundle of His.

Background One of the most critical phases of carotid endarterectomy (CEA) is the carotid cross-clamping test, which is a concrete evaluation of efficacy of collateral cerebral perfusion. Some studies revealed a strong correlation between tolerance to carotid cross-clamping and postoperative transient ischemic attack (TIA)/stroke complications. The aim of the study is to make a global analysis of supra-aortic trunks (SAT) and circle of Willis (CoW) patency to predict the tolerance to carotid cross-clamping preoperatively. Methods We observed retrospectively 503 patients who underwent CEA under local anesthesia between January 2012 and 2017. We analyzed single preoperative risk factors, drug therapy, and vessels patency of the group of patients who did or did not present neurological symptoms at carotid cross-clamping. Afterward, we created a cerebral perfusion score (PTOT) to estimate the efficacy of collateral cerebral perfusion and we compared the results from both groups. The score ranges from 0 (hypothetical total occlusion of the SAT and CoW) to 0.65 in case of patency of all arterial districts. Moreover, we evaluated postoperative complication rates. Results Patients with previous neurological symptoms, female gender, and diabetes correlate with a lower tolerance to carotid cross-clamping (odds ratio: 2.57, 2.78, and 2.57, respectively; P value Conclusions The efficacy of cerebral mechanisms of compensation during carotid cross-clamping reflects the capability of the brain to adapt to ischemic insults, and this also correlates with the postoperative risk of TIA/stroke. It is possible to identify preoperatively patients with a higher risk of neurological intolerance at carotid cross-clamping. This score could be a useful method to make a further stratification of risk of neurological complications and eventually to prefer a general anesthesia and the use of shunt for those with PTOT

This research work discusses a control strategy to enhance the transient response of the fuel cell and boost the real and reactive power flow from grid connected to fuel cell. The current output of the fuel cell depends on the availability of hydrogen in the fuel cell stack, a battery bank is implemented to supply the transient current and to prevent it from hydrogen saturation. The battery should only supply when there is a transient. During steady state the total power is produced by the fuel cell by regulating its hydrogen input. A prototype of the system will be created to study a control scheme which regulates the current from an input source and a battery which is connected to a dc motor. The control philosophy is based on d-q transformation and subsequently generating a reference signal that is tracked by an IGBT based inverter. The speed of the motor is controlled using pulse with modulation. The dynamic modeling of the standalone fuel cell that is connected to a dc motor is carried out using MATLAB/SIMULINK platform. The simulation results show that the control scheme works well, although the dynamic response of the system can be improved. The testing carried on the prototype proves that the concept works well, but a hydrogen control scheme should be developed to improve the efficiency of the control scheme.

Current guidelines recommend caution in prescribing concomitant use of direct-acting oral anticoagulants (DOACs) and antiepileptic drugs due to drug-drug interactions leading to potential risk of DOACs subtherapeutic concentration and treatment failure. Herein we report a significant interaction between carbamazepine (CZP) and apixaban, causing subtherapeutic concentration of the drug in a patient with atrial fibrillation who had a transient ischemic attack (TIA) episode. Another anti-Xa DOAC, edoxaban, administered to the patient after TIA occurrence did not show significant interaction with CZP. In addition to confirm that cautions should be used when antiepileptic and DOACs are concomitantly prescribed, the present case also demonstrates that, in the management of certain subsets of patients who need anticoagulant treatment, measurement of DOAC plasma concentration can help guide a personalized management and avoid adverse clinical outcomes.

Accepted: 2019-01-18, 資料番号: SA1005188000

This paper aims to study the three-dimensional transient flow-field properties of the gas–liquid dual-fluid atomizer, which has high flow capacity and low energy consumption. The two-phase atomization process of air and water, the negative pressure gradient near the porous medium and the recirculation flow inside the atomizer were numerically simulated and analyzed. Primarily, the influence of the air flow velocity on the water flow velocity at the water inlet was numerically studied. Furthermore, it was proven that the simulated results agree well with the experimental data. Thereafter, the variations in the inlet’s water flow velocity and vortex current zone size were studied in detail with changes in the orifice diameter and outlet pipe length. The results indicated that the water absorption improves as the air flow velocity increases. There is a suitable orifice diameter to maximize water flow and maximize the secondary atomization. The water flow velocity becomes larger and the secondary atomization improves as the length of the outlet pipe increases. The larger the vortex region, the smaller the droplet size. This study could provide theoretical data and guidance for the optimization design of dual-fluid atomizers.