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Acute Decompensated Heart Failure after Transcatheter Aortic Valve Implantation: A Ca...
Hong Nyun Kim
Dong Heon Yang

Hong Nyun Kim

and 1 more

December 26, 2022
Transcatheter aortic valve implantation (TVAI) is a widely used treatment for aortic stenosis. The complication rates of TAVI have decreased over time, owing to the improvements in procedural skills.We encountered acute decompensated heart failure cause by stress induced cardiomyopathy or ventricular stunning as a rare and fatal complication of TAVI.
Covid 19 in Temara-Skhirat: Prevalence in symptomatic young adults using the PANBIOS®...
ABBAS ERMILO HAROUN
Majdouline Obtel

ABBAS ERMILO HAROUN

and 6 more

December 26, 2022
Background: Rapid antigen tests have emerged to deal with the Covid 19 pandemic. Rapid diagnosis of SARS-CoV-2 infection is essential to reduce the spread of the disease. The aim of this study was to estimate the prevalence of COVID-19 infection in Temara-Skhirat in symptomatic young adults through PANBIOS® test Methods: A prospective observational prevalence was conducted at the center in September 2021. Two investigators participated in data collection which included all symptomatic young adult patients. The diagnostic performance of the PANBIOS® and the PCR was carried out with the JAMOVI to calculate the sensitivity and the specificity. Results: Among 206 symptomatic participants, the mean age was 38 ± 12 years and majority were women 59%. 80% of the population had benefited from the anti-covid vaccine. The median duration of symptoms was 4 days; the most common symptoms were respectively fatigue 62%, headache 52%, fever 48%, cough 34%, loss of smell 25%, loss of taste 24%, sore throat 22%. Results revealed 23% of positive covid tests carried out with the PANBIOS® test vs 30% with the PCR test. The calculated medical decision between PCR vs PANBIOS® test showed a very high specificity of 95.7% and a sensitivity of 69.4%. There was a concordance between the PANBIOS® test and the PCR. Conclusion: The sensitivity and specificity of the PANBIOS® vs PCR test are similar to those described in WHO recommendations. It is a Useful test for controlling the spread of Covid 19 allowing identification of active infection and isolation of positive patient
Crawling speed control of a snake robot along a cable based on the Hopf oscillator
zhiyong yang
fan wang

zhiyong yang

and 4 more

December 26, 2022
To make the snake robot crawl quickly along the high-voltage cable, this paper employs the Simulated Annealing Algorithm (SAA) to find the optimal step size for the spiral-winding gait of the snake robot and improve its crawling speed along a high-voltage cable. First, a robotic spiral-winding gait is designed based on a snake-like robot configuration and the crawling environment along a wire. Next, the double-chain Hopf oscillator is used to generate the spiral-winding gait for the snake-like robot. After that, based on the snake robot’s position, the SAA is employed to improve the crawling speed of the snake robot by finding the optimal step size of the spiral-winding gait. Finally, the CoppeliaSim software is used to analyze the optimization effect of the speed of the snake robot crawling along the wire. The results highlight that the maximum crawling speeds of the snake robot are 0.8868 cm/s, 0.8843 cm/s, 0.8598 cm/s, and 0.7971 cm/s, which are 18.01%, 8.16%, 11.01%, and 12.16% lower than the maximum speed obtained using the sampling fit method when the wire friction coefficients are 0.3, 0.4, 0.5, and 0.6. This simulation results verify the effectiveness of the optimized control algorithm.
Assessment of human gait after total knee arthroplasty by dynamic time warping algori...
Reza Abbasi-Kesbi
Mohammad Fathi

Reza Abbasi-Kesbi

and 3 more

December 26, 2022
Today, the elderly population is increasing and they endure many drawbacks, especially defects in their knee joints which lead to improper gait. To solve this problem, their knee joint can be replaced with knee arthroplasty. In this letter, the level of improvement in the human gait before and after total knee arthroplasty (TKA) surgery is investigated using the Dynamic Time Wrapping (DTW) algorithm. For this purpose, several volunteers who have problems with their knees incorporate in a test before and after TKA surgery, and data of gait analysis is collected. Then, the obtained data is compared with a reference using the DTW algorithm. The outcome results illustrate an improvement of 89\% - 97\% by the proposed algorithm after TKA surgery. Therefore, patients can see improvement with high speed and accuracy that result in more promising for using TKA surgery.
Re-examining a Strong Recommendation Based on Low-Quality Evidence in Acute Chest Syn...
Charles S. Hemenway

Charles S. Hemenway

December 26, 2022
A document by Charles S. Hemenway. Click on the document to view its contents.
Fixed time event-triggered control for high-order nonlinear uncertain systems with ti...
Panpan Yang
Xuyang Wang

Panpan Yang

and 3 more

December 28, 2022
The fixed time event-triggered control for high-order nonlinear uncertain systems with time-varying state constraints is investigated in this paper. First, the event-triggered control (ETC) mechanism is introduced to reduce data transmission in the communication channel. In consideration of the physical constraints and engineering requirements, time-varying barrier Lyapunov function (BLF) is deployed to make the system states confined in the given time-varying constraints. Then, the radial basis function neural networks (RBF NNs) is used to approximate the unknown nonlinear terms. Further, the fixed time stability strategy is deployed to make the system achieve semiglobal practical fixed time stability (SPFTS) and the convergence time is independent of the initial conditions. Finally, the proposed control scheme is verified by two simulation examples.
Clinic Reported Facilitators and Barriers to Pediatric Cancer Survivor Care Delivery...
Victoria Krauss
Ann Mertens

Victoria Krauss

and 9 more

December 26, 2022
Background: Childhood cancer survivors need regular, long-term survivor care. The Children’s Oncology Group (COG) recommends that pediatric cancer patients receive ongoing, evidence-based surveillance for late-effects beginning two years after cancer therapy completion. A third of survivors are not engaging in long-term survivorship care. This study assessed barriers and facilitators to follow-up survivorship care through the perspectives of pediatric cancer clinic representatives. Methods: As part of a hybrid implementation-effectiveness trial, a representative from 12 participating pediatric cancer survivor clinics completed a survey about site characteristics, and a semi-structured interview on barriers and facilitators to survivor care delivery at their institution. Interviews were grounded in the socio-ecological model (SEM) framework and utilized a Fishbone diagram to identify the root causes of a problem. We ran descriptive statistics and conducted thematic analyses of the interview transcripts to create two meta-Fishbone diagrams. Results: Participating clinics (n=12) have existed for at least five years (mean=30, range= 5-97), and half (50%) report seeing 100-200 survivors annually. In the Fishbone diagram, top facilitators were in the SEM domain of Organization, specifically with familiar staff (100%), resource utilization (92%), survivorship-exclusive staff (83%), and clinic processes (83%). Common barriers were in the domains of Organization, Community, and Policy which included technology limits (92%), scheduling issues (92%), insufficient funding/insurance (92%), and distance/transportation (100%). Conclusion: Using the Fishbone diagram was instrumental in understanding multilevel contextual issues related to survivor care delivery for pediatric cancer clinics. Future efforts can develop education, processes, and services to promote cancer follow-up care.
Adaptive Neural & Fuzzy Controller for Exoskeleton Gait Pattern Control Based on...
Anjali Gupta
Vijay Semwal

Anjali Gupta

and 1 more

December 28, 2022
The paper deals with the development of 2-link lower limb extremity manipulator for rehabilitation purposes in bio-medical engineering. The musculoskeletal modeling was performed on the collected human gait data to obtain the joint angles and driving force values for hip and knee movement. The results obtained from the proposed controller were verified using Matlab-Simulink. The robust adaptive RBF neural network and fuzzy sliding mode controller were developed to track the desired trajectory. The OpenSim software was utilized to perform inverse kinematics and inverse dynamics on the musculoskeletal model which is scaled according to the physical dimensions of the experimental subject. The simulation results stated that SMC-RBF network has better tracking rate, less chattering problems and handle unknown uncertainties well. Finally, the results obtained were compared with the existing method with the help of performance index parameters to prove their effectiveness.
Satisfying Strict Deadlines for Cellular Internet of Things through Hybrid Multiple A...
Onur Gamgam
Ezhan  Karasan

Onur Gamgam

and 1 more

December 28, 2022
Latency-constrained aspects of cellular Internet of Things (IoT) applications rely on Ultra-Reliable and Low Latency Communications (URLLC) which highlight research on satisfying strict deadlines. In this study, we address the problem of latency constrained communications with strict deadlines under average power constraint using Hybrid Multiple Access (MA) which consists of both Orthogonal MA (OMA) and power domain Non-Orthogonal MA (NOMA) as transmission scheme options. We aim to maximize the timely throughput, which represents the average number of successfully transmitted packets before deadline expiration, where expired packets still waiting in the buffer are dropped. We use Lyapunov stochastic optimization methods to develop a dynamic power assignment algorithm for minimizing the packet drop rate while satisfying time average power constraints. Numerical results show that Hybrid MA improves the timely throughput compared to conventional OMA by up to 46% and on the average by more than 21% while satisfying average power constraints.
Effect of Ruxolitinb in refractory pruritus in a patient with high-risk polycythemia...
Mohanned  Karrar
mohamed yassin

Mohanned Karrar

and 1 more

December 26, 2022
Polycythemia vera (PV) associated pruritus is recognized as the most excruciating aspect of the disease. However, knowledge of pathophysiology, frequency, and precise character of PV-associated pruritus is limited. Ruxolitinib presented an encouraging and promising outcome in managing PV-related pruritus, especially in patients with symptoms refractory to other treatment modalities.
Design Strategies of the Mantis Shrimp Spike: How the Crustacean Cuticle Became a Rem...
Yann Delaunois
Alexandra Tits

Yann Delaunois

and 8 more

December 25, 2022
Spearing mantis shrimps are aggressive crustaceans using specialized appendages with sharp spikes to capture fishes with a fast movement. Each spike is a biological tool that have to combine high toughness, as required by the initial impact with the victim, with high stiffness and strength, to ensure sufficient penetration while avoid breaking. We performed a multimodal analysis to uncover the design strategies of this harpoon based on chitin. We found that the spike is a slightly hooked hollow beam with the outer surface decorated by serrations and grooves to enhance cutting and interlocking. The cuticle of the spike resembles a multilayer composite: an outer heavily mineralized, stiff and hard region (with average indentation modulus and hardness of 68 and 3 GPa), providing high resistance to contact stresses, is combined with a less mineralized region, which occupies a large fraction of the cuticle (up to 50%) and features parallel fibers oriented longitudinally, enhancing stiffness and strength. A central finding of our work is the presence of a tiny interphase (less than 10 μm in width) based on helical fibers and showing a spatial modulation in mechanical properties, which has the critical task to integrate the stiff but brittle outer layer with the more compliant highly anisotropic parallel fiber region. We highlighted the remarkable ability of this helicoidal region to stop nanoindentation-induced cracks. Using three-dimensional multimaterial printing to prototype spike-inspired composites, we showed how the observed construction principles can not only hamper damage propagation between highly dissimilar layers (resulting in composites with the helical interphase absorbing 50% more energy than without it) but can also enhance resistance to puncture (25% increase in the force required to penetrate the composites with a blunt tool). Such findings may provide guidelines to design lightweight harpoons relying on environmentally friendly and recyclable building blocks.
DNA sensing in the pathological process of ischemic stroke
ShiWen Zhang
ChaoRan Wu

ShiWen Zhang

and 2 more

December 28, 2022
The innate immune response plays an important role in the pathological process of ischemic stroke. Increasing evidence suggests that the inflammatory response triggered by the innate immune system hinders neurological and behavioral recovery after stroke. The perception of abnormal DNA and its downstream effects are an important part of the innate immune system. The abnormal DNA is the major inducing factor for innate immune response and is sensed by a series of DNA sensors. In this review, we discussed the multiple roles of DNA sensing in the pathological process of ischemic stroke, with a special focus on DNA sensors Toll-like receptor 9 (TLR9), absent in melanoma 2 (AIM2) and cyclic GMP-AMP synthase (cGAS).
The induction of a specific mental set for problem solving is accompanied by increase...
Ze Zhang
Tengteng Tan

Ze Zhang

and 5 more

December 28, 2022
A mental set is a cognitive bias induced by the successive application of a specific strategy; developing a specific mental set prevents individuals from generating more direct and creative ways of solving novel problems. The neural mechanisms underlying mental set induction are unclear. We predicted that the repeated application of a specific strategy leads to increasing similarity of the related neural representations. To test this hypothesis, representation similarity analysis (RSA) was used to identify brain regions whose neural encoding patterns showed increases in representational similarity (RS) during the first, second, third, and fourth induction trials, which utilized the same type of ordinary radical-level “loose” chunk decomposition (LCD) strategy. This induction would consequently restrict one’s ability to solve the probe trials that required a different strategy (insightful stroke-level “tight” chunk decomposition, TCD). We found that from the first to the final LCD trial, regions for attentional control, mental operation, and the default mode network (DMN)-based processing showed increased RS. These RS increases positively predicted the activation of the anterior cingulate cortex (ACC) and medial frontal lobe when solving TCD probe trials, which in turn modulated the impacts of the RS increase in the process of mental set inducing on the degree of representational changes in regions for perceptual, operative, and executive processing on TCD trials. Thus, increased similarities of neural representational patterns in the goal-directed manipulation and spontaneous processing DMN systems may underlie mental set induction; these neural changes interacted with conflict resolution and representational changes when solving novel problems.
Afrinophilina orapa: a new genus and species of Paederinae (Coleoptera: Staphylinida...
Sandiso Mnguni
Ian McKay

Sandiso Mnguni

and 2 more

December 25, 2022
A new genus and species of a staphylinid beetle, Afrinophilina orapa gen. et sp. n., is described using a single well-preserved compression fossil from an Upper Cretaceous fossil insect deposit, the Orapa Diamond Mine in Botswana. Afrinophilina is placed in the extant subfamily Paederinae based on concealed antennal insertions, and hypomeron with a well-developed post-coxal process. It is placed among the Pinophilini based on an elongated procoxae (as long as the profemora), broad, oval, fully exposed trochantin, and a conspicuous second abdominal segment. The new species is placed in the Pinophilina, rather than the Procirrina, based on the presence of well-preserved pair of paratergites on segments III-VIII. Characters which may distinguish this new species from other Pinophilina include the lack of an emarginate shape of the rear margins of the elytra, broad neck, and having two pairs of paratergites on each side of segments III-VI. This is the earliest occurrence of a member of the Pinophilina. It is the first member of the Pinophilina from the Southern Hemisphere, particularly the African continent. Similarly, compared to other fossil staphylinids, the fossil also portrays morphological stasis dating back to the Cretaceous, thereby suggesting a punctuated equilibrium pattern of evolution.
ANALYSIS OF ELECTROSEISMIC CONVERSION IN AN UNBOUNDED ROUGH SURFACE
Sen Zhang

SEN ZHANG

December 25, 2022
Electroseismics is a procedure that uses the conversion of electromagnetic to seismic waves in a fluid-saturated porous rock due to the electrokinetic phenomenon. This paper concerns the time-domain analysis of such an electroseismic conversion problem in an unbounded structure in three dimensions. Using an exact transparent boundary condition and suitable interface conditions, we study an initial- boundary value problem for the coupling of Maxwell's equations and the Biot's equations. The well-posedness and stability are established for the reduced problem. Our proof is based on the method of energy, the Lax-Milgram theorem, and the inversion theorem of the Laplace transform. Moreover, a priori estimates with explicit dependence on the time are achieved for the quantities of electric filed and solid-fluid fields by taking special test functions for the time-domain variational problem.
Some results for a system of NLS arising in optical materials with χ3 nonlinear respo...
Yingxin Duan
Guoqing Zhang

Yingxin Duan

and 1 more

December 25, 2022
In this paper, we investigate the nonlinear Schödinger equations with cubic interactions, arising in nonlinear optics. To begin, we prove the existence results for normalized ground state solutions in the L 2 -subcritical case and L 2 -supercritical case respectively. Our proofs relies on the Concentration-compactness principle, Pohozaev manifold and rearrangement technique. Then, we establish the nonexistence of normalized ground state solutions in the L 2 -critical case by finding that there exists a threshold. In addition, based on the existence of the normalized solutions, we also establish the blow-up results are shown by using localized virial estimates, and a new blow-up criterion which is related to normalized solutions.
Experimental Study on Lightning Attachment Manner of the ice-melting Wind Turbine Bla...
LingFeng Jiang
Zhenglong Jiang

LingFeng Jiang

and 5 more

December 28, 2022
Wind turbines often suffer from lightning strikes, iceing and other disasters. The installation of an electrothermal ice-melting device on the blade can effectively remove icing, but it will increase the risk of lightning strikes on the blade. In order to study the change of lighting attachment manner and the reliability of the existing standard lightning protection device after the blade is retrofitted with ice-melting device. This paper designs a 1:30 scaled-down rotatable 3WM ice-melting wind turbine blade for long gap lightning discharge test. Comparing the interception efficiency of the lightning receptors before and after the installation of the ice-melting device on the blade, the results show that when the lightning leader develops on the windward side of the blade, the ice-melting blade has the phenomenon of lightning receptor failure, lightning strike at the junction of the ice-melting device and the blade body. In the most serious case, the protection efficiency of the lightning receptor is only 55%. The ice-melting device ‘ shields ’ some of the lightning receptor, and the charge around the blade is distributed in an arc shape after the blade rotates, so that the ice-melting device is broken down at a lower voltage. Through the lightning strike probability model of ice-melting blade, it is found that there is a great risk of lightning at the junction of ice-melting device and blade body. The results reveal the lightning attachment manner of the ice-melting blade and further guide its lightning protection design.
Effects of grazing intensity on richness and composition of rhizosphere and non-rhizo...
Yang Yang
Zhang Hao

Yang Yang

and 6 more

December 25, 2022
1.Overgrazing-induced grassland degradation has become a severe ecological problem worldwide. The diversity and composition of soil microbial communities are responsive to grazing disturbance. Yet, our understanding is limited with respect to the effects of grazing intensity on bacterial and fungal communities, especially in plant rhizosphere. 2.Using a long-term (15 years) grazing experiment, we evaluated the richness and composition of microbial communities in both rhizosphere and non-rhizosphere regions, under light, moderate, and heavy intensities of grazing, in a semiarid grassland. We also examined the relative roles of grazing-induced changes in some abiotic and biotic factors in affecting the richness and composition of microbial communities. 3.Our results showed that the responses of soil bacteria to grazing intensity differed greatly between rhizosphere and non-rhizosphere, and so did soil fungi. Specifically, the bacterial richness decreased markedly under moderate and heavy grazing in rhizosphere soil, whereas little impact on the fungal richness was observed. For microbial composition, with the increase in grazing intensity, an increase in dissimilarity among bacterial communities was observed, and this trend also held true for the fungal communities. Hierarchical partitioning analyses indicated that the bacterial composition in rhizosphere was primarily driven by root nitrogen and soil nitrogen concentrations while that in non-rhizosphere by soil available phosphorus. In addition, soil available phosphorus played an important role in affecting the fungal composition in both rhizosphere and non-rhizosphere regions. 4.Synthesis: This study provides direct experimental evidence that the richness and composition of microbial communities were severely altered by heavy grazing in a semiarid grassland. Thus, to restore the grazing-induced, degraded grasslands, we should pay more attention to the conservation of soil microbe in addition to vegetation recovery.
Brugada Syndrome and Anesthesia: A Systematic Review
Zafar Aleem Suchal
Ahmad Afzal

Zafar Aleem Suchal

and 2 more

December 25, 2022
Brugada Syndrome is an inherited disorder causing specific changes on electrocardiogram (ECG) pattern of right bundle branch block and persistent ST elevation in right precordial leads increases the risk of cardiac arrest and fatal arrhythmia. Patients with brugada are prone to abnormal cardiac rhythms which can be induced by alcohol, stress, vagal stimulation, and certain medications. Thus medications are divided into different classes from I to III with I carrying the most evidence for potential arrhythmia while III being the least likely. Exceptional care needs to be taken to avoid anesthetic and analgesic during surgeries for such patients as several of the known anesthesia medications can lead to arrhythmia in these patients. In this review we aimed to study the effect different anesthetic and analgesic medication could have on patients with brugada syndrome. We conducted a systematic review following PRISMA guidelines to query PubMed, Embase, Cochrane library and ProQuest electronic databases. Mesh combinations and synonyms of “Brugada Syndrome”, “Anesthesia”, “Analgesics” were used. We included all original human studies that focused on outcomes of anesthetic and analgesics on patients with brugada. After screening 1149 studies, we included 49 articles consisting of a total of 1414 subjects for qualitative analysis. We found local analgesics to be least likely to lead to potential arrhythmic complications with other systemic and inhaled agents having a risk although the risk varied because of multitude of reasons ranging from type of drug to patient factors like the patient’s condition and type of Brugada. We concluded that anesthetic although could be used for individuals with Brugada the type of anesthetic to be used should be selected keeping the potential cardiac risk under consideration.
Deriving and testing parameter values for a parsimonious soil erosion model
Thomas Brunner
Thomas Weninger

Thomas Brunner

and 9 more

December 25, 2022
Every application of soil erosion models brings the need of proper parametrization, i.e., finding physically or conceptually plausible parameter values that allow a model to reproduce measured values. No universal approach for model parametrization, calibration and validation exists, as it depends on the model, spatial and temporal resolution and the nature of the datasets used. We explored some existing options for parametrization, calibration and validation for erosion modelling exemplary with a specific dataset and modelling approach. A modified version of the Morgan-Morgan-Finney (MMF) model was selected, representing a balanced position between physically-based and empirical modelling approaches. The resulting calculator for soil erosion (CASE) model works in a spatially distributed way on the timescale of individual rainfall events. A dataset of 142 high-intensity rainfall experiments in Central Europe (AT, HU, IT, CZ), covering various slopes, soil types and experimental designs was used for calibration and validation with a modified Monte-Carlo approach. Subsequently, model parameter values were compared to parameter values obtained by alternative methods (measurements, pedotransfer functions, literature data). The model reproduced runoff and soil loss of the dataset in the validation setting with R 2 adj of 0.89 and 0.76, respectively. Satisfactory agreement for the water phase was found, with calibrated saturated hydraulic conductivity (k sat) values falling within the interquartile range of k sat predicted with 14 different PTFs, or being within one order of magnitude. The chosen approach also well reflected specific experimental setups contained in the dataset dealing with the effects of consecutive rainfall and different soil water conditions. For the sediment phase of the tested model agreement between calibrated cohesion, literature values and field measurements were only partially in line. For future applications of similar model applications or datasets, the obtained parameter combinations as well as the explored methods for deriving them may provide guidance.
The state-of-the-art technic of stereotactic radioablation for the treatment of cardi...
Alireza Abdshah
Farzad Masoudkabir

Alireza Abdshah

and 12 more

December 25, 2022
Cardiac arrhythmias are a leading cause of mortality, morbidity, and sudden cardiac death (SCD). Current treatment strategies for ventricular tachycardia (VT) are effective for many patients; however, in several cases, this does not result in a cure. Despite significant clinical improvements, conventional catheter ablation remains relatively unsuccessful in achieving the best outcomes in some challenging cases. Stereotactic arrhythmia radioablation (STAR), which delivers precise high-dose radiation to well-defined targets with minimal damage to surrounding tissue, is emerging as a new potential treatment option, having the potential to be used for patients at high risk for catheter ablation or who have refractory VT. Ongoing studies and preliminary experiences on f the efficacy of STAR in patients with refractory VT have shown a reduction in VT recurrence and a promising early safety profile. However, STAR is in its infancy, and clinical evidence on its efficacy and safety is limited; thus, conclusions regarding the efficacy of STAR should be drawn with caution. Further investigation of long-term efficacy and tolerability is ongoing to substantiate this promising therapeutic option better. The present review describes the background and general principles, pretreatment procedures, clinical implications, and toxicity of STAR therapy.
The Role of Groundwater Flow in a Montane, Semi-Arid, Headwater Catchment
Lauren Salberg
Suzanne Anderson

Lauren Salberg

and 2 more

December 25, 2022
Groundwater is critical in sustaining streamflow, especially in headwater catchments, because of its ability to supply baseflow. In water-limited arid and semi-arid mountain environments, the need to characterize groundwater recharge and discharge has grown in tandem with demands to manage current and future water resources. However, studying groundwater in complex terrain is challenging due to limited field measurements. Nearly a decade of monitoring in Gordon Gulch in the Colorado Front Range provides an opportunity to study such an environment. The field data is used to parameterize and calibrate a groundwater flow model (MODFLOW-NWT). Model results reveal that groundwater is recharged primarily during one to two recharge periods each year, driven by spring snowmelt coupled with rain or by intense/prolonged summer rain. Gordon Gulch is a net gaining stream, with greater fluxes from groundwater to stream in lower Gordon Gulch and during springtime. Groundwater is discharged to the stream via long, deep flowpaths sourced from upper Gordon Gulch and from hillslopes, and via short, shallow flowpaths in lower Gordon Gulch. Modelled groundwater accounts for approximately 16 to 34% of baseflow in the stream. Using Gordon Gulch as a case study, this model and data analysis contribute to a larger effort to understand and constrain the mechanisms driving groundwater recharge and groundwater-stream exchanges in semi-arid, headwater catchments.
Cellular and humoral responses to fourth SARS-CoV-2 vaccination in a real life cohort...
Julia M. Berger
Pia Gattinger

Julia M. Berger

and 5 more

December 25, 2022
Cellular and humoral responses to fourth SARS-CoV-2 vaccination in a real life cohort of patients with cancer To the Editor,Patients with cancer are at increased risk of adverse outcomes when infected with SARS-CoV-2 and show an impeded humoral and cellular immune response to vaccination (1). A fourth vaccination increased the humoral immunity against SARS-CoV-2 including Omicron sublineages better than Tixagevimab and Cilgavimab (2). However, data on effects of a fourth SARS-CoV-2 vaccination on cellular immunity, particularly in relation to antibody responses, are scarce (3).Methods : To analyze specific cellular immunity after fourth immunization, SARS-CoV-2 specific CD4+ / CD8+ T-cell responses were prospectively measured in 7 patients with histologically confirmed neoplastic disease before and at the next clinical visit after fourth vaccination against the SARS-CoV-2 spike protein (S) and the receptor binding domain (RBD). Moreover, IgG against S and RBD of Omicron (BA.4) and Hu-1, respectively were assessed. A >1.1-fold increase of antigen-specific proliferated cells and antibody levels compared to baseline was defined as a vaccine response. Assays were performed as described previously (4). This study was approved by the Ethics Committee of the Medical University of Vienna (vote 1427/2022) and performed according to the Declaration of Helsinki and its amendments. Informed consent was obtained from all included participants. Descriptive statistical analysis was performed using GraphPad Prism, Version 9.4.1 (San Diego, California, USA).Results : Six patients with solid tumors and one immunocompetent patient with CNS lymphoma (median age [range] 64 years [45-78], 7 men) were prospectively included and received a fourth vaccination (one mRNA-1273 and six BNT162b2). Of these patients, 6 patients were undergoing active anti-neoplastic therapy. The baseline blood sampling was performed in median 7 months (range 5-9 months) after the third vaccine dose, while the follow-up blood sampling was done in median 21 days (range: 19-30 days) after the fourth vaccination (Table 1) .Overall, clear signs of response on either humoral, cellular, or combined humoral and cellular levels were observed in 6/7 patients. However, a striking intra- and interpatient heterogeneity of immune response patterns was evident (Figure 1 ). Only 2/7 patients (patients 4 and 6) responded with combined increases in S and RBD specific CD4+ and CD8+ T-cell proliferation. All other patients showed inconsistent increases in T-cell activity with low vaccination responses in at least one T-cell subpopulation. Additionally, humoral response did not consistently coincide with cellular vaccine responses: patients 4 and 6, who had no or only a mild (e.g. IgG against S 0.97-fold change and 2.23-fold change, respectively) increase in antibody levels had a pronounced cellular vaccine response (e.g. CD4 against S 4-fold change and 134-fold change, respectively). Interestingly, patient 5 increased antibody levels against S without corresponding CD4+ responses. Moreover, patients with distinct antibody increases only showed mediocre vaccine responses on cellular level (Patients 1, 2 and 7). One patient (patient 3), showed severely impeded humoral and cellular vaccine responses to the fourth vaccination applied 433 days after administration of the last B-cell targeting treatment (Rituximab).Conclusions : The most important limitation of this prospective study is its small sample size and the lack of a control group. However, we observed high intra- and interpatient heterogeneity with clear indications of humoral, cellular, or combined response to fourth vaccine in most patients under active treatment. Of note, our observation indicates long-lasting impairment of specific immune responses after a fourth vaccine on both humoral and cellular levels as long as 36 months after last rituximab administration. These findings highlight the need for reliable identification of and development of management strategies for SARS-CoV-2 vaccine non-responders among patients receiving anti-cancer therapies.References :1. Mairhofer M, Kausche L, Kaltenbrunner S, Ghanem R, Stegemann M, Klein K et al. Humoral and cellular immune responses in SARS-CoV-2 mRNA-vaccinated patients with cancer. Cancer Cell. 2021;39 :1171–1172.2. Mair MJ, Mitterer M, Gattinger P, Berger JM, Valenta R, Fong D et al. Inhibition of SARS-CoV-2 Omicron BA.1 and BA.4 Variants After Fourth Vaccination or Tixagevimab and Cilgavimab Administration in Patients With Cancer. JAMA Oncol Published Online First: September 2022. doi:10.1001/jamaoncol.2022.42263. Debie Y, Van Audenaerde JRM, Vandamme T, Croes L, Teuwen L-A, Verbruggen L et al. Humoral and Cellular Immune Responses against SARS-CoV-2 after Third Dose BNT162b2 following Double-Dose Vaccination with BNT162b2 versus ChAdOx1 in Patients with Cancer. Clin Cancer Res 2022;:OF1–OF12.4. Gattinger P, Niespodziana K, Stiasny K, Sahanic S, Tulaeva I, Borochova K et al. Neutralization of SARS-CoV-2 requires antibodies against conformational receptor-binding domain epitopes. Allergy2022;77 :230–242.
An adaptive control scheme for switched nonlinear cyber-physical systems against stat...
Xiao Wang
Ping Zhao

Xiao Wang

and 1 more

December 28, 2022
This paper considers the problem of adaptive control against deception attacks for a class of switched nonlinear cyber-physical systems (CPSs), in which each subsystem has more general and unknown nonlinearities. Specifically, an adaptive controller is designed for CPSs with unknown switching mechanisms to mitigate the impact of state-dependent sensor attacks and input-dependent actuator attacks. Compared with the existing researches, the actuator attacks considered in our paper are input-dependent, which means the controller is substantially attacked, besides, the signs of unknown time-varying gains caused by state-dependent sensor attacks and input-dependent actuator attacks are all unknown. To deal with these scenarios, Nussbaum-type functions are introduced. In addition, by constructing a common Lyapunov function for all subsystems, the closed-loop system signals are proved to be globally bounded under arbitrary switchings. Finally, we give a simulation example of a continuously stirred tank reactor system with state-dependent sensor attacks and input-dependent actuator attacks to illustrate the effectiveness of our results.
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