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Wild honey poisoning: A case report from Central Nepal
Dipendra Dahal
Ramesh Lamichhane

Dipendra Dahal

and 8 more

November 20, 2023
Wild honey poisoning: A case report from Central Nepal
A macroevolutionary analysis of cryptic colouration in sexually dichromatic grasshopp...
Víctor Ramírez-Delgado
Martin  Serrano-Meneses

Víctor Ramírez-Delgado

and 2 more

November 20, 2023
Background matching and disruptive colouration are defense mechanisms of animals against visual predators. Disruptive colouration tends to evolve in microhabitats that are visually heterogeneous, while background matching is favored in microhabitats that are chromatically homogeneous. This is one of the few comparative studies that have tested the relative impact of background matching and disruptive markings in the chromatic evolution. Controlling for the phylogeny, we explored the evolution of the colouration and the marking patterns in the sexual dichromatic and widely distributed Neotropical grasshoppers of the genus Sphenarium. These grasshoppers represent an excellent model to investigate the evolution of cryptic colouration on insects due to the heterogeneity of the environments where they have evolved. We found a correlation between the grasshoppers' colouration and disruptive markings with the chromatic properties of their environments that was inferred by the levels of precipitation during the rainy season. The results suggest that colours and marks patterns could evolve due to predation pressures. Colour in both sexes could offer camouflage that is not perfectly background matched to a single habitat but instead offers a degree of resemblance to multiple backgrounds. Moreover, we found that males and females chromatic properties differ between them and precipitation levels where the species are found. This suggests that the sexes have diverged in their response to the environments, favoring the evolution of sexual dichromatism in these grasshoppers.
Nonlinear Extended State Observer-based Sliding Mode Control Strategy of PMSM against...
NN Z
Qiming Wang

NN Z

and 2 more

November 20, 2023
This paper presents a nonlinear extended state observer-based sliding mode control strategy of Permanent magnet synchronous motor (PMSM) to address the poor performance of conventional double closed-loop PI control under tough conditions. A variable speed reaching law is proposed to balance the rapidity and robustness under the fixed parameters of the exponential reaching law. Then, a nonlinear extended observer is proposed to ensure the estimated accuracy of disturbance and rotational speed. Then, a deadbeat current prediction control is designed to replace the conventional dual PI current control to ensure efficient current loop control of PMSM. Furthermore, the stability proof of the proposed control strategy is developed. Experimental results are given to validate the effectiveness of the proposed control strategy. The proposed control approach can effectively improve speed and current control performance with tough conditions (e.g., speed and torque step-changes, periodic disturbances).
The effect of pairing assistance under medical alliance policy on healthcare utilizat...
Haoqing Tang
Mingyue Li

Haoqing Tang

and 4 more

November 20, 2023
Pairing assistance (PA) of health professionals between county hospitals and township health centers is one of the key components of the reform of medical alliances in China to strengthen the development of health workforce in primary health care (PHC). This study aims to examine the effect of PA on healthcare utilization for patients with chronic diseases in rural areas. Two waves of National Health Services Survey (2013 and 2018) were used. A total of 13893 and 22725 rural residents with chronic diseases were included in the 2013 and 2018 waves, respectively. Multiple logistic regressions were used to examine the associations between PA and outpatient and inpatient service utilization in PHC. Chow test was used to examine the difference between PA in two models. Among rural patients with chronic diseases, two-week outpatient visits increased from 22.69% to 27.54%, and annual hospitalization admission increased from 20.72% in 2013 to 25.44%. PA was associated with a significant decrease in outpatient visits (p<0.001) in 2018 after controlling for individual and county characteristics. Patients in PA counties were 1.45 times (95% CI 1.10-1.90) more likely to use PHC outpatient care in 2013, but the difference disappeared in 2018 (OR=0.85, 95% CI 0.71-1.01). PA did not reverse the downward trend in the share of PHC outpatient visits. PA under medical alliances in China provides a potential model for building integrated people-centered health systems for other low- and middle-income countries.
A 128×128 SPAD LiDAR Sensor with Column-Parallel 25ps Resolution TA-ADCs
Na Tian
Zhe Wang

Na Tian

and 7 more

November 20, 2023
This letter presents a design of single photon avalanche diode (SPAD) light detection and ranging (LiDAR) sensor with 128×128 pixels and 128 column-parallel time-to-analog-merged-analog-to-digital converts (TA-ADCs). Unlike the conventional TAC-based SPAD LiDAR sensor, in which the TAC and ADC are separately implemented, we proposed to merge the TAC and ADC by sharing their capacitors, thus avoiding the analog readout noise of TAC’s output buffer, improving the conversion rate, and reducing chip area. The reverse stop-start logic is employed to reduce the power of the TA-ADC. Fabricated in a 180nm CMOS process, our prototype sensor exhibits a timing resolution of 25ps, a DNL of +0.30/-0.77 LSB, an INL of +1.41/-2.20 LSB, and a total power consumption of 190mW. A flash LiDAR system based on this sensor demonstrates the function of 2D/3D imaging with 128×128 resolution, 25k inter-frame rate, and sub-centimeter ranging precision.
The first high-altitude autotetraploid haplotype-resolved genome assembled (Rhododend...
Zhen-Yu Lyu
Xiong-Li Zhou

Zhen-Yu Lyu

and 7 more

November 20, 2023
Rhododendron nivale subsp. boreale Philipson et M. N. Philipson is a kind of ornamental alpine woody flower from mountaintop scrub at an altitude of approximately 4000 meters. Despite ecological significance, the lack of genomic resources has hindered a comprehensive understanding of its evolutionary and adaptive characteristics in high-altitude environments. In this work, we sequenced and assembled the genome of R. nivale subsp. boreale, which is an assembly of the first subgenus Rhododendron and the first high-altitude woody flowering autotetraploid. The assembly included 52 pseudochromosomes, which belonged to 4 haplotypes, harbor 127,810 predicted protein-coding genes. Comparative genomic analysis revealed that R. nivale subsp. boreale originated as a neopolyploid resulting from R. nivale and experienced two rounds of ancient polyploidy event. Transcriptional expression analysis showed that the expression differences of alleles were common, randomly distributed in the genome. We identified signatures of positive selection involved not only in adaptations to mountaintop ecosystem (response to UV radiation and developmental regulation), but also in strategy of autotetraploid reproduction (meiotic stabilization). Notably, highly expressed ERF VIIs aid survival in hypoxic mountaintop environments. Meanwhile, the expanded families was enriched in brassinosteroid (BR) biosynthesis, which enhances adaptability to the dramatic changes in alpine weather, is likely mediated by the increased number of cytochrome P450 (CYP) genes. This valuable genome of mountaintop woody flowering autotetraploids not only provides genetic resources for studying high-altitude polyploid formation but also provides new insights for understanding the evolution and adaptation mechanism of high-altitude plants.
A new perspective on variation of voriconazole steady-state valley concentration in C...
Xu Hao
Yinyu Zhao

Xu Hao

and 9 more

November 20, 2023
Background: Voriconazoleis(VRC) often used in complex therapeutic environments for the treatment and prevention of invasive fungal infections. The steady-state valley concentration (Cminss) of VRC not only varies between individuals, but also within individuals, which is difficult to fully explain by pharmacogenomic theory. It is necessary to propose a new perspective to explain the variation of voriconazole steady-state valley concentration. Objectives: Based on the regulation of ADME gene expression by DNA methylation, this study aimed to explore the effect of CYP2C19 DNA methylation level on the VRC Cminss. Methods: In this study, 116 concentration points were divided into low concentration group (Cminss<1.0mg/L), standard concentration group (Cminss =1.0-5.5mg/L) and high concentration group (Cminss>5.5mg/L) according to Voriconazole Cmin standard range of 1.0-5.5 mg/L. The effect of CYP2C19 DNA methylation was highlighted by predisposition score matching to exclude other confounding factors. Results: The CYP2C19 CpG25 methylation level was different between low concentration group and standard concentration group (p=0.047). There was no difference in the CYP2C19 DNA methylation between the high concentration group and the standard concentration group, but there were significant differences in CRP (p<0.001), Alb (p=0.007) and T-BIL (p=0.024) between the high concentration group and the standard concentration group. Conclusions: The VRC Cminss in the low concentration group may be related to the methylation degree of CYP2C19 CpG25 site, while the VRC Cminss in the high concentration group may be unrelated to the methylation degree of CYP2C19 but related to the levels of CRP, Alb and T-BIL.
CLINICAL EVIDENCE OF PANCREATIC RECOVERY IN CHILDREN WITH CYSTIC FIBROSIS ON IVACAFTO...
Corinne Muirhead
Sydney Walker

Corinne Muirhead

and 3 more

November 20, 2023
TITLE: CLINICAL EVIDENCE OF PANCREATIC RECOVERY IN CHILDREN WITH CYSTIC FIBROSIS ON IVACAFTORTo the Editor,Pediatric research has shown that young children with cystic fibrosis (CF) and treated with ivacaftor have seen improvements in pancreatic function. KIWI was a 24-week safety and efficacy trial of ivacaftor in children aged 2-5 years with CF (1). KLIMB was an 84-week open label extension of KIWI (2). Patients enrolled in KIWI revealed an average increase of 99.8 ug/g in fecal elastase (FE). Before beginning ivacaftor, 26 of 27 patients were pancreatic insufficient. After 24 weeks, 25% of these 26 patients had FE results demonstrating pancreatic sufficiency (>200 ug/g) (1). These improvements in FE were maintained during the 84-week KLIMB extension (2).In the ARRIVAL Study, a younger population was studied. Infants aged 12-24 months previously diagnosed with pancreatic insufficiency were assessed (3). After 24 weeks post ivacaftor initiation, six of nine, or 67%, of the infants had repeat FE values of >200 ug/g, consistent with pancreatic sufficiency, as well as evidence of decreased pancreatic inflammation noted with reduction in immunoreactive trypsinogen.Based on this data we instituted a new protocol for repeat FE monitoring in all patients with pancreatic insufficiency who started on ivacaftor by the age of two years. If FE is normal (>200 ug/g), discontinuation of pancreatic enzyme replacement therapy (PERT) is considered along with ongoing monitoring of clinical symptoms and adjustments to vitamin and diet recommendations as indicated.Below is a review of our cohort of pediatric patients who were currently, had been consistently treated with ivacaftor, and were assessed for current pancreatic function by repeat FE testing. All FE values were collected prior to initiation of elexacaftor/tezacaftor/ivacaftor (ETI) in those newly eligible. Nine patients at our CF center who were on PERT have started ivacaftor in the last 6 years with a mean current age of 4.9 years (SD 1.7). The median age of ivacaftor initiation was 1.1 years (range 0.4 - 2). The mean duration of treatment is 3.9 years (SD 1.3).Seven patients had a repeat FE result >200 ug/g. Six of the seven pancreatic insufficient patients presented as newly pancreatic sufficient as evidenced by a FE result of >200 ug/g compared to previous result of <200 ug/g. Patient I was included in this cohort as he was treated with PERT for clinical symptoms of pancreatic insufficiency even though his baseline FE values were above 200 ug/g.The six newly pancreatic sufficient patients started ivacaftor between 0.4 and 1.1 years of age. Our recovery data of 75% is close to the rate seen in the ARRIVAL study. We calculated binomial probability for pancreatic recovery in this small case control series using 0.67 factor based on previous data in ARRIVAL (4). This resulted in a 28% favorability of success.Unsurprisingly, the rate of recovery was higher in the younger age of initiation of ivacaftor than that seen in the older 2–5 year-old cohort in KIWI. A correlation between pancreatic recovery and younger age of initiation was also noted in a recently published multi-center retrospective study of all available CFTR modulators and PE recovery (5). In this study, of the 15 patients with FE results of 200 or greater, 10 had been treated with ivacaftor as their initial modulator therapy. Based on the demographic data, 62.5% of those treated with ivacaftor had pancreatic recovery, which is similar to our cohort data.We urge CF Centers to institute clinical protocols to recheck pancreatic elastase to assess for restoration of pancreatic function in all pediatric patients treated with PERT on ivacaftor. Subsequently, CF Centers should establish processes for discontinuing PERT, monitoring fat soluble vitamins, and adjusting diet as indicated. Resulting medication adjustments will significantly impact the treatment burden and cost for these children and their families. Those with pancreatic restoration should be monitored for symptoms of pancreatic insufficiency as well as growth trends at routine intervals and pursue repeat FE as indicated based on clinical assessment.This study was approved by the Oregon Health and Science University Institutional Review Board (IRB#26442).
Fusion estimation for state-saturated multi-rate systems with integral measurement an...
Changcheng Shi
Long Xu

Changcheng Shi

and 3 more

November 20, 2023
The fusion estimation problem for a class of multi-rate systems (MRS) subject to state saturation is examined in this paper. varying sensors have varying sensor sampling rates (SSRs), and in MRS, the system’s status update rate (SUR) and the SSR can differ from one another. In addition, to incorporate the requirements of actual engineering practice, the measurement output of sensors is influenced by the sensor resolution and the phenomenon of integral measurements. The aim of this paper is to design an appropriate set of local estimators for each sensor node, taking into account the effects of integral measurement, sensor resolution and multi-rate sampling mechanism. Then, Design of the upper bound on the error covariance of the estimator can be obtained by solution of the matrix difference equation, and the relevant filter parameter is determined by minimizing the obtained upper bound. For local state estimation, an acceptable fusion estimating approach based on the covariance intersection (CI) method is given, and its consistency is demonstrated. Lastly, the effectiveness and appropriateness of the suggested multi-rate fusion estimation approach are confirmed by a simulated example.
Surveillance of seasonal influenza viruses during the COVID-19 pandemic in Tokyo, Jap...
Hidenori Takahashi
Hiroki Nagamatsu

Hidenori Takahashi

and 13 more

November 20, 2023
Introduction: COVID-19 pandemic led to significant reductions in influenza detection worldwide, making influenza trends challenging to monitor. The number of influenza cases decreased significantly in Japan, raising concerns about the potential risk of decreased immunity to influenza in the population. Our single-center study aimed to investigate influenza trends before and during the COVID-19 pandemic in Tokyo, Japan. Materials and Methods: This cross-sectional study included patients of all ages who visited Tokyo Shinagawa Hospital between April 1, 2018, and March 31, 2023. Influenza and COVID-19 tests were conducted using Quick Navi-Flu2 and polymerase chain reaction (PCR). We analyzed data from before and during the COVID-19 epidemic, based on patient background, hospitalization, and deaths, collected from medical records. Results: A total of 12,577 influenza tests were conducted, with approximately 100 tests consistently performed each month even in the influenza off-season. Throughout the observation period, 962 positive cases were identified. However, no cases were observed for 27 months between March 2020 and November 2022. Cases of influenza A were observed again in December 2022, and cases of influenza B were observed again in March 2023, similar to the influenza incidence reports from Tokyo. The positivity rate during the 2022–2023 winter season was lower than before the COVID-19 epidemic and decreased in elderly patients, with no hospitalizations or deaths observed. Conclusion: This single-center study provided actual trend data for influenza patients before and during COVID-19 outbreaks in Tokyo, which could offer insights into the potential impact and likelihood of influenza virus infection in Japan.
Associations between severe influenza-complicated thromboembolism events, intensive c...
WEI CHUN LEE
Che-Chia  Chang

WEI CHUN LEE

and 13 more

November 20, 2023
Background: Compelling evidence suggests associations between influenza infection and thromboembolism (TE) events. Risk factors related to the outcomes of severe influenza-complicated TE in intensive care unit (ICU) patients remain unknown. Methods: A retrospective cohort study was conducted, recruiting consecutive patients with thromboembolism (TE) events admitted to the intensive care unit (ICU) between December 2015 through December 2018 at our institution in Taiwan. A study cohort of patients with severe influenza (n=108) and a control group of patients with severe community-acquired pneumonia (n=192) were included. Associations between complicated TE, length of ICU stay, 90-day mortality were evaluated. Results: Thromboembolism events prevalence was significantly higher in ICU patients with severe influenza than in ICU patients with severe CAP (21.3% vs. 5.7%, respectively; p<0.05). The ratio of mechanical ventilation use, length of mechanical ventilation use, ICU stay and 90-day mortality increased significantly in ICU patients with severe influenza after developing TE compared with patients without TE (all p<0.05). Influenza infection and hypertension are the risk factors for thromboembolic events in patients with severe influenza (p< 0.05). Besides, complicated TE and severity of APACHE II score are risk factors for 90-day mortality in ICU patients with severe influenza (p< 0.05). Conclusions: ICU patients with severe influenza and complicated TE have an increased risk of extended ICU stay and 90-day mortality compared to patients with severe CAP. Risk is significantly increased in patients with higher APACHE II score. this study may help define better strategies for early recognition and prevention of severe influenza-complicated TE.
FUTURE PROGNOSIS FOR CARDIOVASCULAR COMPLICATIONS ASSOCIATED WITH SARS-COV-2: A PHARM...
Anand Vijayakumar P R
Aditya jha

Anand Vijayakumar P R

and 5 more

November 20, 2023
Background: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused the coronavirus disease 2019 (COVID-19), which is associated with cardiovascular problems and serious lung damage. COVID-19 patients with comorbid conditions are at a significantly elevated risk of increased morbidity and mortality. Angiotensin-converting enzyme 2 (ACE2) and transmembrane protease serine 2 (TMPRSS2) are the two key host contributing factors for the severity and pathogenesis of COVID-19. The principal SARS-CoV-2 entrance receptor, ACE2, is expressed equally in most organs and produces cardio-protective vasodilators by physically degrading angiotensin II, the main controller of the Renin-Angiotensin Aldosterone System. However, treatment for cardiovascular disease (CVD) commonly involves RAAS inhibitors, which may increase ACE2 expression. Objective: To summarize the pharmacological molecular discoveries into the processes of viral infection and its consequences for cardiovascular disease and to offer suggestions for the practical management and treatment of COVID-19-related cardiovascular injury. Methods: This review focuses on the important considerations related to the cardiovascular manifestations of COVID-19 and discusses the various mechanisms of COVID-19 that contribute to its molecular and pharmacological presentation of cardiovascular injury. Results: The host-pathogen relationship began with ACE2’s attachment to the S-protein and proceeded with TMPRSS2’s proteolytic cleavage of the viral spike (S)-protein and ACE2. Currently discovered protein-protein interactions explain the uniqueness of SARS-CoV-2 infection. Conclusion: COVID-19 is associated with cardiovascular problems and serious lung damage. ACE2 and TMPRSS2 are key host contributing factors for the severity and pathogenesis of COVID-19. The molecular discoveries into the processes of viral infection and its consequences for cardiovascular disease provide important considerations for the management and treatment of COVID-19-related cardiovascular injury.
Analysis of Safe Electricity Consumption on Load Side Based on Attack and Defence Gam...
Pengcheng Du

Pengcheng Du

November 20, 2023
With the improvement of digitalization and intelligence in the power system, the safe operation of the power system is facing enormous challenges. The safe use of electricity on the load side is the key to achieving safe and reliable power system operation. The detection party needs amounts of human and material resources when the power network is attacked. In response to the current difficulties of low detection ability and high detection costs, this paper proposes an attack and defence game model that considers the differences between different nodes, ensuring the safety and economy of electricity consumption while reducing energy waste. At first, the structure of smart meters and the attack characteristics of intruders are summarized, and a basic attack and defence game model is constructed. The Nash equilibrium is then solved, and the optimal strategy for the game between the defender and the intruder is given to balance the relation between detection performance and energy consumption. In response to the differences generated by each node, strategies for attackers to launch attacks on different nodes and the setting of optimal thresholds for other nodes in the defence system are explored. Finally, case studies verify that the proposed model could reduce the cost of intruder detection while ensuring a specific detection rate.
Extreme temperatures reduce copepod performance, but increase in the gut thermophilic...
Quyen Vu
Linh Pham

Quyen Vu

and 7 more

November 20, 2023
Copepods are one of the most abundant invertebrate groups in the seas and oceans and are a significant food source for marine animals. However, copepods are also particularly vulnerable to elevated temperatures, yet it is unknown the role of the gut microbiome in shaping copepod susceptibility to warming. We addressed this fundamental knowledge gap by assessing key life history traits (survival, development, reproduction), and changes in the relative abundance of the gut microbiome in the tropical calanoid copepod Acartia sp. in response to warming (26, 30, and 34°C). Gut microbiomes of copepods were analyzed using high throughput DNA sequencing of V1–V9 of 16S rRNA hypervariable regions. Copepod performance was better at 30°C than at 26°C as indicated by higher survival, faster growth rate and development, and higher fecundity. However, all of these parameter strongly decreased when temperature increased to 34°C. We recorded 1,262,987 amplicon sequence reads, corresponding to 392 total operational taxonomic units at 97% similarity. The gut content of all copepods contained Cyanobacteria, Proteobacteria, Bacteroidetes, Planctomycetes, Actinobacteria, and Acidobacteria. Thermophilic Proteobacteria were found dominantly at high temperatures (30°C and 34°C). At 34°C, Vibrio was the only dominant group, accounting for 70% of species found in copepod guts, which may partly associated with the reduced growth and survival of Acartia sp.. The next logical step is to explore the functional role of all gut bacterial groups in relation to changes in copepod fitness, which will fundamentally advance our mechanistic understanding of the adaptability of tropical copepods and, more generally, marine invertebrates to the warming climate.
Further enlargement of the thoracoabdominal aortic aneurysm after hybrid repair, trea...
Maciej Antkiewicz
Michał Krzywiecki

Maciej Antkiewicz

and 5 more

November 20, 2023
A document by Maciej Antkiewicz. Click on the document to view its contents.
Prediction of Breast Cancer through Fast Optimization Techniques Applied to Machine L...
Yekini Shehu
W Cholamjiak

Yekini Shehu

and 2 more

November 20, 2023
This paper studies new accelerated optimization algorithms and applied the algorithms to prediction of breast cancer through machine learning approach. To do this, we first introduce new fast CQ algorithms and obtain weak convergence results. In one of our proposed algorithms (inertial-type CQ Algorithm), the inertial choice could be negative and even greater than 1 with no on-line rule imposed in order to obtain convergence results. This is a major improvement over other inertial-type algorithms in the literature where inertial choices are restrictive to [0 ,1) and on-line rule is imposed. Then we validate the applicability of the proposed CQ algorithms to real-life applications by predicting breast cancer by updating the optimal weight in machine learning. We use the mammographic mass dataset from the UC Irvine machine learning repository that is available on the UCI website as a training set to show the superiority of our algorithms over existing ones in the literature.
A Review of Password-less User Authentication Schemes.
Abdullahi Arabo
Tunde Oduguwa

Abdullahi Arabo

and 1 more

November 20, 2023
Since the demise of the password was predicted in 2004, different attempts in industry and academia have been made to create an alternative for the use of passwords in authentication, without compromising on security and user experience. This review examines password-less authentication schemes that have been proposed since after the death knell was placed on passwords in 2004. We start with a brief discussion of the requirements of authentication systems and then identify various password-less authentication proposals to date. We then evaluate the truly password-less and practical schemes using a framework that examines authentication credentials based on their impact on user experience, overall security, and ease of deployment. The findings of this review observe a difficulty in balancing security with a user experience compared to that of passwords in new password-less schemes, providing the opportunity for new applied research to leverage existing knowledge and combine technologies and techniques in innovative ways that can address this imbalance.
The Usage of wireless Intelligent control and UAVenabled B5G/6G network in fuzzy adap...
xuguang xu
liang yu

xuguang xu

and 1 more

November 20, 2023
In the Inertial Navigation System/Geomagnetic Navigation System (INS/GNS) integrated navigation system, divergence and measurement noise that change with environments frequently occur must be reduced in order to increase the accuracy and stability of autonomous, passive navigation.Base on the Unscented Kalman Filter,we can combine Convergence of intelligent sensing as well as computing, and control for UAV-enabled B5G/6G network to deal with change in the variance and mean value of the latest information. First,the noise’s covariance in the model is modified “online” to change the  estimation of mean square deviation error and filtering gain of Kalman filtering by using 5G/6G network; Then, through UAV-enabled B5G/6G network and  intelligent sensing to change the scaling factor of weight in sigma sampling is  adaptively changed to solve the nonlocal effect in UT transform and improve the effciency and accuracy of the navigation deposition system. The simulation results show that the fuzzy adaptive Kalman filter is very efficient for INS/GNS integrated navigation systems.It overcome the shortcomings of traditional filtering method and improve the accuracy of filtering.
A compact rectangular waveguide TE10 to TE20 mode converter with coplanar and codirec...
Guangjian Deng
Shao yi Xie

Guangjian Deng

and 3 more

November 20, 2023
A compact rectangular waveguide TE10 to TE20 mode converter is proposed in this paper. It consists of a dominant mode waveguide and an overmoded waveguide connected with coplanar and codirectional configuration to promise a compact cross section. A septum is inserted into the overmoded waveguide to divide it into two channels. The converter utilizes a Riblet-hybrid-like structure and two humps inserted in narrow walls of each of the two channels. The inherent 90-degree phase of the hybrid together with another 90-degree phase difference between the two channesl created by the humps can realize half-wavelength phase relation and excite TE20 mode. The cross section size of cavity structure of the mode converter is about 1.52 λ ×0.61 λ at center frequency of 9.5 GHz. Tested results demonstrate that within a fractional bandwidth of 3.3%, the mode conversion efficiency is better than 97.7% with a return loss of larger than 20 dB. The peak power capacity is larger than 470 kW at common air condition.
Active Gate Driver for SiC MOSFET Based on Switching Transient Feedback
Cheng Xu
Yiru Miao

Cheng Xu

and 1 more

November 20, 2023
Due to internal parasitic parameters and junction capacitance, silicon carbide (SiC) power devices have great voltage and current overshoot and high-frequency switching oscillation during high-speed switching process, which seriously affects the operation reliability of SiC-Based converters. In this paper, the switching characteristics of SiC MOSFET are analyzed to reveal the mathematical relationship between gate driving current and voltage/current overshoot. Then, a new active gate drive circuit with variable driving current is proposed. In the current or voltage rising stage of the switching process, the gate current is actively regulated, so the overshoot and oscillation of the voltage and current can be effectively suppressed, through the direct detection and feedback of the transient drain current change rate dIdd/t, drain-source voltage changes rate dVds/dt and driving voltage of SiC MOSFET Vgs. Finally, experimental results show that the proposed method can effectively reduce voltage/current overshoot by 30% ~ 50%, and improve the operation reliability of SiC MOSFET converter.
Fluvial biogeomorphological feedbacks from plant traits to the landscape: lessons fro...
Dov Corenblit
Johannes Steiger

Dov Corenblit

and 1 more

November 20, 2023
Research in fluvial biogeomorphology largely aims to promote our understanding of the interactions between riparian vegetation and fluvial morphodynamics within riverine ecosystems. Starting at the end of last century, Angela M. Gurnell has made a major contribution to fluvial geomorphology by considering, in addition to water flow and sediment transport, explicitly riparian, and later also aquatic vegetation and thus significantly promoted the fluvial biogeomorphological approach from its beginnings until today. The objective of the present paper is to present a set of studies and results obtained over the last twenty years by the authors and many collaborators, including Angela M. Gurnell, on a panel of French rivers: Tech, Garonne, Isère and Allier Rivers. In particular, feedback mechanisms between fluvial morphodynamics and riparian vegetation dynamics were investigated directly in the field and also using high resolution remote sensing at the scale of individual plants, populations, communities and landscapes, as well as during semi-controlled ex situ experiments at the scale of individual plants. Collectively, the authors’ research conducted over the past 20 years contributed to elucidate some key aspects of the feedback dynamics between the lowest and highest levels of the riparian ecosystem organisation. This article presents and discusses those key aspects. The gradually obtained results contributed to better understand and quantify feedbacks between river morphodynamics and vegetation at nested spatiotemporal scales, from plant species traits to the riverine landscape. Furthermore, the biogeomorphological approach advocated for more than twenty years now, has clearly helped to contribute to the enlargement of the discipline of geomorphology to ecology as well as evolutionary ecology, and to the development of a more integrative vision to study earth surface processes.
Towards Biogeomorphic River Restoration: Vegetation as a Critical Driver of Physical...
Rossa O'Briain
Dov Corenblit

Rossa O'Briain

and 3 more

November 20, 2023
The current focus of river restoration on flow and sediment transfer without proper consideration of vegetation as a key structuring agent, beyond its stabilising effect, is too simplistic. We contend that vegetation has an essential role in shaping the physical fluvial environment and should be considered equally alongside hydrogeomorphic processes in restoration projects. In support, we introduce engineer plants as important controls, along with flowing water and transported sediments, on the morphodynamics of river systems and associated physical habitat development. The effect of vegetation on channel planform is then summarised, the influence of vegetation on hydrogeomorphic connectivity is outlined, and then the role of vegetation in landform development and habitat provision, as encapsulated in the fluvial biogeomorphic succession model, is described. We then present examples demonstrating how vegetation has contributed to the recovery of degraded rivers through biogeomorphic processes. Finally, we advance the concept of biogeomorphic river restoration by proposing principles to support a closer synthesis of the component sciences and list key areas for practitioners to focus on.
Assessing Motivational Biases in Brain and Behavior: Event-Related Potential and Resp...
Christopher Sege
James Lopez

Christopher Sege

and 3 more

November 20, 2023
The Approach-Avoidance Task (AAT) is designed to 1) measure the implicit motivated action biases that are instantiated by emotional stimuli, and 2) assess the changes in such biases that drive psychiatric disorder. To establish AAT sensitivity to emotional action bias at a neural level, some work has measured event-related potential (ERP) correlates — however, a lack of research with unpleasant, pleasant, and neutral stimuli together and also a common focus on psychiatric disorder-matched (rather than generally evocative) content limits foundational conclusions that can be drawn. In current research, then, 38 subjects completed an AAT where normative (rather than idiosyncratic) unpleasant, pleasant, and neutral images were shown with a color border indicating if a joystick should be rapidly pushed or pulled to decrease or increase image size. Using generally arousing stimuli, response times (RTs) were found to be faster on unpleasant push compared to unpleasant pull trials, t(37)=2.4, p=.02, and 32-sensor electroencephalography (EEG) also revealed that amplitude of a stimulus-response conflict-related ERP – the N200 – was reduced on unpleasant compared to neutral push trials and un-pleasant push compared to unpleasant pull trials, t(32)=5.5, p<.001. In addition, preliminary exploration of individual differences suggested that relevant variables of dimensional trait anxiety, depression, and anxiety disorder treatment seeking status did not impact RT- or N200-indicated emotional biases. Together, then, findings are consistent with a neurobehavioral avoidance bias for unpleasant stimuli while also suggesting a need to further test whether selecting images for idiosyncratic relevance is critical to revealing individual variations in emotional bias.
SUCCESSFUL RAPID LIPOSOMAL AMPHOTERICIN-B DESENSITIZATION IN PEDIATRIC CASE SERIES AN...
Emine Misirlioglu
Cankat Geniş

Emine Misirlioglu

and 5 more

November 20, 2023
Background: Amphotericin B is the broadest-spectrum polyene group antifungal agent. In the presence of an infection caused by a fungal agent resistant to alternative antifungal drugs, desensitization may be the only option to continue treatment. However, there is insufficient information and consensus regarding Amphotericin B desensitization protocols in the pediatric age group. Objective: In this study, we present our experience with five cases where successful desensitization protocols were applied with Liposomal Amphotericin B (AmBisome®; LAMB), along with a review of the literature on pediatric cases. We also provide a sample desensitization protocol that we successfully applied. Methods: In this retrospective study, pediatric patients who continued their treatment with the successful rapid desensitization protocol conducted at the Pediatric Allergy and Immunology Clinic of the Ministry of Health Ankara City Hospital between September 2019 and September 2023 were examined. In our study, desensitization protocols were applied based on Castell et al.’s desensitization protocol. Results: Between 2019 and 2023, five patients aged between 5 and 12 years, including three with hematologic malignancies, one with tuberculosis meningitis, and one with chronic granulomatous disease, were referred to us due to the development of anaphylaxis during their treatment with LAMB. Anaphylaxis is diagnosed clinically, considering the European Academy of Allergy and Clinical Immunology (EAACI). A 16-step desensitization protocol was prepared using LAMB solutions at four different dilutions (0.001 mg/ml, 0.01 mg/ml, 0.1 mg/ml, 1 mg/ml). Each solution consisted of four steps with a 15-minute infusion for each step. Patients was premedicated with 1 mg/kg/dose methylprednisolone and an antihistamine. Conclusion: The data we present on the successful application of a sample protocol to five cases, particularly in a pediatric setting, is a significant and valuable contribution to the field. This can provide important insights and potentially serve as a reference for medical professionals working with similar cases in the future.
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