检索结果-南通市图书馆

A Study of the TPS Based Beam-Matching concept for Medical Linear Accelerators at a Tertiary Hospital

在线全文

学校读者我要写书评

暂无评论

International Journal of Medical Physics, clinical Engineering and Radiation Oncology 2024年第1期13卷 16-25页

作者： ntombela n. Lethukuthula Rovetto J. nicolas nethwadzi c. Lutendo Mpumelelo nyathi Department of Radiation Oncology Steve Biko Academic Hospital Pretoria South Africa Department of Medical Physics University of Pretoria Pretoria South Africa Department of Medical Physics Sefako Makgatho Health Sciences University Ga-Rankuwa South Africa

The flexibility in radiotherapy can be improved if patients can be moved between any one of the department’s medical linear accelerators (LInAcs) without the need to change anything in the patient’s treatment plan. For this to be possible, the dosimetric characteristics of the various accelerators must be the same, or nearly the same. The purpose of this work is to describe further and compare measurements and parameters after the initial vendor-recommended beam matching of the five LInAcs. Deviations related to dose calculations and to beam matched accelerators may compromise treatment accuracy. The safest and most practical way to ensure that all accelerators are within clinical acceptable accuracy is to include TPS calculations in the LInAcs matching evaluation. Treatment planning system (TPS) was used to create three photons plans with different field sizes 3 × 3 cm, 10 × 10 cm and 25 × 25 cm at a depth of 4.5 cm in Perspex. calculated TPS plans were sent to Mosaiq to be delivered by five LInAcs. TPS plans were compared with five LInAcs measurements data using Gamma analyses of 2% and 2 mm. The results suggest that for four out of the five LInAcs, there was generally good agreement, less than a 2% deviation between the planned dose distribution and the measured dose distribution. However, one specific LInAc named “Asterix” exhibited a deviation of 2.121% from the planned dose. The results show that all of the LInAcs’ performance were within the acceptable deviation and delivering radiation dose consistently and accurately.

关键词： Radiotherapy Beam-Matching Linear Accelerator Dosimetry

Learning about good nutrition with the 5-color front-of-package label"nutri-Score":an experimental study

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Food Science and Human Wellness 2024年第3期13卷 1195-1200页

作者： Robin c.Hau Klaus W.Lange University of Applied Sciences Landshut Landshut 84036Germany Faculty of Human Sciences University of RegensburgRegensburg 93040Germany

The nutri-Score is a 5-color front-of-pack nutrition label designed to provide consumers with an easily understandable guideline to the healthiness of food *** impact that the nutri-Score may have on consumers'choices is unclear since different experimental paradigms have found vastly different effect *** the present study,we have investigated how student participants change a hypothetical personal 1-daydietary plan after a learning phase during which they learn about the nutri-Scores of the available food *** were instructed to compose a healthy diet plan in order that the question of whether the nutriScore would improve their ability to compose a healthy dietary plan could be investigated,independent of the question of whether they would apply this knowledge in their ordinary *** found a substantial(cohen's d=0.86)positive impact on nutritional quality(as measured by the nutrient Profiling System score of the Food Standards Agency)and a medium-sized(cohen's d=0.43)reduction of energy *** content reduction was larger for participants who had initially composed plans with higher energy *** results suggest that the nutri-Score has the potential to guide consumers to healthier food *** remains unclear,however,whether this potential will be reflected in real-life dietary choices.

关键词： nutri-Score Front-of-package label nudge nutrition Health

Effects of layer interactions on instantaneous stability of finite Stokes flows

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 69-84页

作者： chen ZHAO Zhenli cHEn c.T.MUTASA Dong LI School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China

The stability analysis of a finite Stokes layer is of practical importance in flow control. In the present work, the instantaneous stability of a finite Stokes layer with layer interactions is studied via a linear stability analysis of the frozen phases of the base flow. The oscillations of two plates can have different velocity amplitudes, initial phases, and frequencies. The effects of the Stokes-layer interactions on the stability when two plates oscillate synchronously are analyzed. The growth rates of two most unstable modes when δ nd δ = δ*/h*, where δ*and h*are the Stokes-layer thickness and the half height of the channel, respectively. However, their vorticities are different. The vorticity of the most unstable mode is symmetric, while the other is asymmetric. The Stokes-layer interactions have a destabilizing effect on the most unstable mode when δ nd have a stabilizing effect when δ > 0.68. However, the interactions always have a stabilizing effect on the other unstable mode. It is explained that one of the two unstable modes has much higher dissipation than the other one when the Stokes-layer interactions are strong. We also find that the stability of the Stokes layer is closely related to the inflectional points of the base-flow velocity profile. The effects of inconsistent velocity-amplitude, initial phase, and frequency of the oscillations on the stability are analyzed. The energy of the most unstable eigenvector is mainly distributed near the plate of higher velocity amplitude or higher oscillation frequency. The effects of the initial phase difference are complicated because the base-flow velocity is extremely sensitive to the initial phase.

关键词： finite Stokes layer instantaneous stability Stokes-layer interaction asynchronous oscillation

Elevated brain temperature under severe heat exposure impairs cortical motor activity and executive function

在线全文

学校读者我要写书评

暂无评论

Journal of Sport and Health Science 2024年第2期13卷 233-244页

作者： Xiang Ren Tan Mary c.Stephenson Sharifah Badriyah Alhadad Kelvin W.Z.Loh Tuck Wah Soong Jason K.W.Lee Ivan c.c.Low Health and Social Sciences Singapore Institute of TechnologySingapore 138683Singapore Human Potential Translational Research Programme Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117597Singapore centre for Translational Magnetic Resonance Research Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117549Singapore Department of Physiology Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117593Singapore Heat Resilience and Performance centre Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117510Singapore n.1 Institute for Health National University of SingaporeSingapore 117456Singapore campus for Research Excellence and Technological Enterprise(cREATE) Singapore 138602Singapore

Background:Excessive heat exposure can lead to hyperthermia in humans,which impairs physical performance and disrupts cognitive *** heat is a known physiological stressor,it is unclear how severe heat stress affects brain physiology and ***:Eleven healthy participants were subjected to heat stress from prolonged exercise or warm water immersion until their rectal temperatures(T_(re))attained 39.5℃,inducing exertional or passive hyperthermia,*** a separate trial,blended ice was ingested before and during exercise as a cooling *** were compared to a control condition with seated rest(normothermic).Brain temperature(T_(br)),cerebral perfusion,and task-based brain activity were assessed using magnetic resonance imaging ***:T_(br)in motor cortex was found to be tightly regulated at rest(37.3℃±0.4℃(mean±SD))despite fluctuations in T_(re).With the development of hyperthermia,T_(br)increases and dovetails with the rising T_(re).Bilateral motor cortical activity was suppressed during high-intensity plantarflexion tasks,implying a reduced central motor drive in hyperthermic participants(T_(re)=38.5℃±0.1℃).Global gray matter perfusion and regional perfusion in sensorimotor cortex were reduced with passive *** function was poorer under a passive hyperthermic state,and this could relate to compromised visual processing as indicated by the reduced activation of left lateral-occipital ***,ingestion of blended ice before and during exercise alleviated the rise in both T_(re)and T_(bc)and mitigated heat-related neural ***:Severe heat exposure elevates T_(br),disrupts motor cortical activity and executive function,and this can lead to impairment of physical and cognitive performance.

关键词： Brain functional activity cognition Heat stress Hyperthermia Motor function

Radiative decays D*(s)→ D(s)γ in covariant confined quark model

在线全文

学校读者我要写书评

暂无评论

chinese Physics c 2024年第2期48卷 45-56页

作者： c.T.Tran M.A.Ivanov P.Santorelli Q.c.Vo Department of Physics HCMC University of Technology and EducationVo Van Ngan 1700000 Ho Chi Minh CityVietnam Bogoliubov Laboratory of Theoretical Physics Joint Institute for Nuclear Research141980 DubnaRussia Dipartimento di Fisica"E.Pancini" Universitàdi Napoli Federico ⅡComplesso Universitario di Monte S.AngeloVia CintiaEdificio 680126 NapoliItaly Istituto nazionale di Fisica nucleare Sezione di Napoli80126 NapoliItaly University of Science 700000 Ho Chi Minh CityVietnam

Radiative decays D((s))*→D((s))γare revisited in light of new experimental data from the BaBar and BESⅢ*** radiative couplings gD*Dγencoding nonperturbative QcD effects are calculated in the framework of the covariant confined quark model developed by *** compare our results with other theoretical studies and experimental *** couplings(in GeV-1)|g(D*+D+γ)|=0.45(9)and|g(D*0D0γ)|=1.72(34)calculated in our model agree with the corresponding experimental data|g(D*+D+γ)|=0.47(7)and|g(D*0D0γ)|=1.77(16).The most interesting case is the decay Ds*→Dsγ,for which a recent prediction based on light-cone sum rules at next-to-leading order|gDs*Dsγ|=0.60(19)deviates from the first(and only to date)lattice QcD result|gDs*Dsγ|=0.11(2)at nearly3σ.Our calculation yields|gDs*Dsγ|=0.29(6),which falls somehow between the two mentioned results,although it is larger than those predicted in other studies using quark models or QcD sum rules.

关键词： covariant quark model radiative decay charmed meson

Pathogenic and therapeutic role of exosomes in neurodegenerative disorders

在线全文

学校读者我要写书评

暂无评论

neural Regeneration Research 2024年第1期19卷 75-79页

作者： christa c.Huber Hongmin Wang Division of Basic Biomedical Sciences Sanford School of MedicineUniversity of South DakotaVermillionSDUSA

neurodegenerative disorders affect millions of people worldwide,and the prevalence of these disorders is only projected to rise as the number of people over 65 will drastically increase in the coming *** therapies exist to aid in symptomatic relief,effective treatments that can stop or reve rse the progress of each neurodegenerative disease are ***,research on the role of extracellular vesicles as disease markers and therapeutics has been intensively ***,30-150 nm in diameter,are one type of extracellular vesicles facilitating cell-to-cell *** are thought to play a role in disease propagation in a variety of neurodegenerative diseases,such as Alzheimer's disease,Parkinson s disease,and amyotrophic lateral ***,the exosomes derived from the patients are an invaluable source of disease *** the other hand,exosomes,especially those derived from stem cells,could serve as a therapeutic for these disorders,as seen by a rapid increase in clinical trials investigating the therapeutic efficacy of exosomes in different neurological *** review summarizes the pathological burden and therapeutic approach of exosomes in neurodegenerative *** also highlight how heat shock increases the yield of exosomes while still maintaining their therapeutic ***,this review concludes with outstanding questions that remain to be addressed in exosomal research.

关键词： aging Alzheimer's disease biomarker drug exosome extracellular vesicle neurodegenerative disease Parkinson's disease therapy

Silk-based nerve guidance conduits with macroscopic holes modulate the vascularization of regenerating rat sciatic nerve

在线全文

学校读者我要写书评

暂无评论

neural Regeneration Research 2025年第6期20卷 1789-1800页

作者： carina Hromada Patrick Heimel Markus Kerbl LászlóGál Sylvia nürnberger Barbara Schaedl James Ferguson nicole Swiadek Xavier Monforte Johannes c.Heinzel Antal nógrádi Andreas H.Teuschl-Woller David Hercher Department Life Science Engineering University of Applied Sciences Technikum WienViennaAustria Austrian cluster for Tissue Regeneration ViennaAustria Ludwig Boltzmann Institute for Traumatology The Research Center in Cooperation with AUVAViennaAustria University clinic of Dentistry Medical University of ViennaViennaAustria Department of Plastic Reconstructive and Aesthetic SurgeryLandesklinikum Wiener Neustadt2700 Wiener NeustadtAustria Department of Anatomy Histology and EmbryologyAlbert Szent-Györgyi Medical SchoolUniversity of SzegedSzegedHungary Medical University of Vienna Department of Orthopedics and Trauma SurgeryDevision of Trauma SurgeryViennaAustria Department of Hand- PlasticReconstructive and Burn SurgeryBG Unfallklinik TuebingenUniversity of TuebingenTuebingenGermany

Peripheral nerve injuries induce a severe motor and sensory deficit. Since the availability of autologous nerve transplants for nerve repair is very limited, alternative treatment strategies are sought, including the use of tubular nerve guidance conduits(tnGcs). However, the use of tnGcs results in poor functional recovery and central necrosis of the regenerating tissue, which limits their application to short nerve lesion defects(typically shorter than 3 cm). Given the importance of vascularization in nerve regeneration, we hypothesized that enabling the growth of blood vessels from the surrounding tissue into the regenerating nerve within the tnGc would help eliminate necrotic processes and lead to improved regeneration. In this study, we reported the application of macroscopic holes into the tubular walls of silk-based tnGcs and compared the various features of these improved silk^(+) tnGcs with the tubes without holes(silk^(–) tnGcs) and autologous nerve transplants in an 8-mm sciatic nerve defect in rats. Using a combination of micro-computed tomography and histological analyses, we were able to prove that the use of silk^(+) tnGcs induced the growth of blood vessels from the adjacent tissue to the intraluminal neovascular formation. A significantly higher number of blood vessels in the silk^(+) group was found compared with autologous nerve transplants and silk^(–), accompanied by improved axon regeneration at the distal coaptation point compared with the silk^(–) tnGcs at 7 weeks postoperatively. In the 15-mm(critical size) sciatic nerve defect model, we again observed a distinct ingrowth of blood vessels through the tubular walls of silk^(+) tnGcs, but without improved functional recovery at 12 weeks postoperatively. Our data proves that macroporous tnGcs increase the vascular supply of regenerating nerves and facilitate improved axonal regeneration in a short-defect model but not in a critical-size defect model. This study suggests that further optimizatio

关键词： axon regeneration blood vessel functional recovery macroporous nerve lesion peripheral nerve repair sciatic nerve silk-based nerve guidance conduit vascularization

Automated Machine Learning Algorithm Using Recurrent neural network to Perform Long-Term Time Series Forecasting

在线全文

学校读者我要写书评

暂无评论

computers, Materials & continua 2024年第3期78卷 3529-3549页

作者： Ying Su Morgan c.Wang Shuai Liu Department of Statistics and Data Science University of Central FloridaOrlandoFL32816-2370USA School of Mathematics and Statistics Beijing Technology and Business UniversityBeijing100048China

Long-term time series forecasting stands as a crucial research domain within the realm of automated machine learning(AutoML).At present,forecasting,whether rooted in machine learning or statistical learning,typically relies on expert input and necessitates substantial manual *** manual effort spans model development,feature engineering,hyper-parameter tuning,and the intricate construction of time series *** complexity of these tasks renders complete automation unfeasible,as they inherently demand human intervention at multiple *** surmount these challenges,this article proposes leveraging Long Short-Term Memory,which is the variant of Recurrent neural networks,harnessing memory cells and gating mechanisms to facilitate long-term time series ***,forecasting accuracy by particular neural network and traditional models can degrade significantly,when addressing long-term time-series ***,our research demonstrates that this innovative approach outperforms the traditional Autoregressive Integrated Moving Average(ARIMA)method in forecasting long-term univariate time *** is a high-quality and competitive model in time series prediction,and yet it requires significant preprocessing *** multiple accuracy metrics,we have evaluated both ARIMA and proposed method on the simulated time-series data and real data in both short and long ***,our findings indicate its superiority over alternative network architectures,including Fully connected neural networks,convolutional neural networks,and nonpooling convolutional neural *** AutoML approach enables non-professional to attain highly accurate and effective time series forecasting,and can be widely applied to various domains,particularly in business and finance.

关键词： Automated machine learning autoregressive integrated moving average neural networks time series analysis

Hierarchical control Strategy for Load Regulation Based on Stackelberg Game Theory considering Randomness

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

cSEE Journal of Power and Energy Systems 2024年第3期10卷 929-941页

作者： Tingyu Jiang Ping Ju c.Y.chung Yuzhong Gong college of Energy and Electrical Engineering Hohai UniversityNanjing 211100China Department of Electrical Engineering City University of Hong KongHong Kong CF624China Department of Electrical and computer Engineering University of SaskatchewanSaskatoonSK S7N 5A9Canada cSEE IEEE

Demand response has been recognized as a valuable functionality of power systems for mitigating power *** paper proposes a hierarchical control strategy among the distribution system operator(DSO),load aggregators(LAs),and thermostatically controlled loads(TcLs);the strategy includes a scheduling layer and an executive layer to provide load *** the scheduling layer,the DSO(leader)offers compensation price(cP)strategies,and the LAs(followers)respond to cP strategies with available regulation power(ARP)*** of the DSO and LAs are modeled according to their behaviors during the load regulation *** game is adopted to capture interactions among the players and leader and to obtain the optimal strategy for each participant to achieve ***,considering inevitable random factors in practice,e.g.,renewable generation and behavior of users,two different stochastic models based on sample average approximation(SAA)and parameter modification are formulated with improved scheduling *** the executive layer,distributed TcLs are triggered based on strategies determined in the scheduling layer.A self-triggering method that does not violate user privacy is presented,where TcLs receive external signals from the LA and independently determine whether to alter their operation *** simulations are performed on the modified IEEE-24 bus system to verify effectiveness of the proposed strategy.

关键词： Demand response hierarchical control load regulation self-triggering method Stackelberg game