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2.
Artículo en Inglés | MEDLINE | ID: mdl-39014250

RESUMEN

PURPOSE: This study delves into the broader implications of artificial intelligence (AI) text generation technologies, including large language models (LLMs) and chatbots, on the scientific literature of otolaryngology. By observing trends in AI-generated text within published otolaryngology studies, this investigation aims to contextualize the impact of AI-driven tools that are reshaping scientific writing and communication. METHODS: Text from 143 original articles published in JAMA Otolaryngology - Head and Neck Surgery was collected, representing periods before and after ChatGPT's release in November 2022. The text from each article's abstract, introduction, methods, results, and discussion were entered into ZeroGPT.com to estimate the percentage of AI-generated content. Statistical analyses, including T-Tests and Fligner-Killeen's tests, were conducted using R. RESULTS: A significant increase was observed in the mean percentage of AI-generated text post-ChatGPT release, especially in the abstract (from 34.36 to 46.53%, p = 0.004), introduction (from 32.43 to 45.08%, p = 0.010), and discussion sections (from 15.73 to 25.03%, p = 0.015). Publications of authors from non-English speaking countries demonstrated a higher percentage of AI-generated text. CONCLUSION: This study found that the advent of ChatGPT has significantly impacted writing practices among researchers publishing in JAMA Otolaryngology - Head and Neck Surgery, raising concerns over the accuracy of AI-created content and potential misinformation risks. This manuscript highlights the evolving dynamics between AI technologies, scientific communication, and publication integrity, emphasizing the urgent need for continued research in this dynamic field. The findings also suggest an increasing reliance on AI tools like ChatGPT, raising questions about their broader implications for scientific publishing.

3.
J Theor Biol ; 588: 111821, 2024 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-38649020

RESUMEN

Fish schooling has the improvement in hydrodynamic propulsive efficiency through the interaction of flow field induced by fish bodies and tail beat. Such energy-saving behaviors due to flow interactions also occur with changes in the flow field caused by structures. We examined the differences between a live fish swimming around a streamlined hydrofoil model prepared to represent fish body and swimming alone in a flow tank. We observed that the fish can remain in the same place without tail beating. It called "drafting" behavior. The analysis of fish drafting showed that fish obtained thrust using a local pressure drop caused by the high velocity flow even in the vicinity of the hydrofoil model at an angle of attack α of 10° to 20°without flow separation, and fish balanced forces by using an α of fish body. This tendency was confirmed in the model experiment using a two-axis load cell, and the forces acting on the fish body was the smallest value when the fish model was placed in the same conditions as a live fish experiment. We also confirmed by simulation and found that the α of fish body generated lift force and counteract the suction force. Above results indicate that a fish can balance the anterior-posterior and lateral direction forces by using a local pressure drop around a hydrofoil model as suction force, and using angle of attack on its body, thereby realizing drafting.


Asunto(s)
Modelos Biológicos , Presión , Natación , Animales , Natación/fisiología , Fenómenos Biomecánicos , Peces/fisiología , Hidrodinámica , Conducta Animal/fisiología
4.
Eur J Appl Physiol ; 124(8): 2379-2388, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38523228

RESUMEN

BACKGROUND: Drafting is a common technique to reduce the drag experienced by elite runners on races, leading to faster finish times. The tactic has been successfully used in previous marathon world records. In the 2023 Chicago Marathon, Kenyan runner Kelvin Kiptum broke the marathon record after a 2:00:35 finish. This feat is impressive considering the lack of use of drafting, despite the availability of two pacers for the majority of the race. METHODS: In this study, the drag faced by Kiptum and his pacers during the race is calculated by means of computational fluid dynamics (CFD). The performance of each runner is evaluated from an energetic standpoint, and the analysis is extended to include more efficient drafting formations. RESULTS: Running in proper formations results in drag reductions in excess of 70% for the main runner. Our results indicate that, by properly using the advantages of drafting, Kiptum could have finished the race at a staggering 1:57:34, a full three minutes better than his own record and 215 s better than the previous world record. CONCLUSION: Proper use of drafting does indeed improve the energetic performance of a runner, allowing for lower race times and potentially helping elite runners in breaking the 2-h barrier for a marathon.


Asunto(s)
Carrera de Maratón , Humanos , Carrera de Maratón/fisiología , Masculino , Rendimiento Atlético/fisiología , Carrera/fisiología , Resistencia Física/fisiología
5.
J Sci Med Sport ; 26(1): 46-51, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36528552

RESUMEN

OBJECTIVES: The main goal of this study was to compare the aerodynamic optimization level in echelon-formation strategy for riders fighting against a crosswind from the best (echelon or diagonal paceline) to the worst riders' configuration (guttered riders). DESIGN: The case reported herein concerned a group of 5 cyclists riding at 30 km/h with a 30 km/h crosswind oriented at 40° to the direction of travel. The effects of the wind, expressed in terms of aerodynamic resistance or pressure, were determined for each cyclist in the different configurations. METHODS: The 3D numerical simulations were performed using a calculation code based on the finite volume method and the Reynolds-averaged Navier-Stokes turbulence model k-kl-ω. RESULTS: The results showed that the lateral force savings, averaged over the whole five-riders group, ranged from 50% in the echelon-optimized configuration to 11% in the guttered straight-line one, compared to a solo rider in the same velocity and windy conditions. Individually, the rider with the best aerodynamic shelter is the 4th rider in the "4 rider echelon + 1 guttered rider" formation (- 53.6% in drag force and - 69.8% in lateral force), while the rider with the worst aerodynamic situation is the leader of the straight paceline (- 0.1% in drag force and - 0.2% in lateral force). CONCLUSIONS: The analysis showed how the spatial management of riders significantly influences drag and lateral forces and supported the idea that avoiding being guttered is the best way to save energy in windy races.


Asunto(s)
Ciclismo , Viento , Humanos , Motivación
6.
Artif Intell Law (Dordr) ; : 1-35, 2022 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-36407875

RESUMEN

In this paper, we present a method for introducing law students to the writing of legal documents. The method uses a machine-readable representation of the legal knowledge to support document assembly and to help the students to understand how the assembly is performed. The knowledge base consists of enacted legislation, document templates, and assembly instructions. We propose a system called LEDAS (LEgal Document Assembly System) for the interactive assembly of legal documents. It guides users through the assembly process and provides explanations of the interconnection between input data and claims stated in the document. The system acts as a platform for practicing drafting skills and has great potential as an education tool. It allows teachers to configure the system for the assembly of some particular type of legal document and then enables students to draft the documents by investigating which information is relevant for these documents and how the input data shape the final document. The generated legal document is complemented by a graphical representation of legal arguments expressed in the document. The system is based on existing legal standards to facilitate its introduction in the legal domain. Applicability of the system in the education of future lawyers is positively evaluated by the group of law students and their TA. Supplementary Information: The online version contains supplementary material available at 10.1007/s10506-022-09339-2.

7.
Front Bioeng Biotechnol ; 10: 978212, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36185434

RESUMEN

In the biomedical field, polyurethane (PU) is widely used in interventional catheters, artificial hearts, artificial blood vessels, orthopedic materials, medical adhesives, and other medical devices. In this paper, a method based on machine vision was proposed to control the drafting and winding accuracy of PU filament in order to solve the problem of centrifugal runout when the mold rotates. The centrifugal runout of the mold directly affected the preparation efficiency and quality of long artificial blood vessel by wet spinning. Through non-contact real-time detection of the filament diameter and the angle between the axis of filament and the axis of mold, the motion parameters of the two motors driving the moving platform and the drafting roller could be adjusted in real time to achieve the purpose of online real-time control of filament drafting and winding accuracy. The vision control method proposed in this paper was used to carry out the PU tube preparation experiment. The visual measurement results of the filament diameter and the included angle were compared with the manual measurement results. The average value of the diameter error is 0.0096mm, and the average value of winding angle is 0.4777°. The results proved the accuracy of the visual measuring method and testified it feasible to using machine vision instead of manual method to detect filament diameter and winding angle. Properties of the prepared PU tube were tested and analyzed. The filament diameter measured by the 3D microscope was about 0.87 mm and significantly smaller than the filament diameter before winding. This indicated that the winding was uniform, the extrusion was tight, and the adhesion was good.

8.
Front Artif Intell ; 5: 963692, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36304960

RESUMEN

An intersemiotic translation is any form of translation that involves at least two different semiotic codes; for example, the translation from words to images, to numerical code, or to non-verbal sounds. One of the most widespread examples of intersemiotic translation in the contemporary world is transposing natural language into machine language in digital environments. In this case, if the source text is a legal text, we encounter a particular type of intersemiotic translation, namely an intersemiotic legal translation in a digital environment. This paper will focus on the intersemiotic legal translation of contracts in digital environments, and is divided into two parts. In the first part (Section Ways of intersemiotically translating a contract using digital tools), we will analyze four possible uses of the intersemiotic translation of contracts in a digital context. In particular, we will highlight the technical characteristics of intersemiotic translation, its limitations, and its potential in different phases of contract management, namely the drafting of the document, the agreement, the archiving of the document, and the execution of contractual clauses. We will examine different digital tools that exploit intersemiotic translation, such as contract drafting tools and online platforms that allow for the conclusion of electronic contracts, document archiving in blockchains, and building smart contracts. When analyzing these uses of intersemiotic translation in the digital environment, we will highlight four types of output that can represent the product of intersemiotic translation in the digital environment: epistemic effects, legal effects, digital effects, and economic effects. In the second part (Section A tool for translating the contract intersemiotically), we will describe a hypothetical prototype that, in light of the four potential uses of intersemiotic translation, could represent a support tool to simplify the communication between professionals and clients through the drafting of legal documents with the aid of dynamic forms and, eventually, with the help of artificial intelligence (AI). Beyond facilitating the dialogue between legal professionals and their clients, we use interfaces to allow clients to create their own drafts of their documents and the lawyer to work on the drafts drawn up by the customer, correct them, and structure them in order to guarantee the validity of the document. The system can also be designed to archive legal documents and private deeds securely and entrust them to a professional by using blockchain technology and automating the execution of some contractual clauses via smart contract protocols.

9.
Artículo en Inglés | MEDLINE | ID: mdl-35954720

RESUMEN

BACKGROUND: Currently, tactics play an important and decisive role in sprint distance triathlons. One of the most decisive tactical elements is drafting in the cycling sector, depending on whether or not it is allowed by the test regulations. The objective was to analyze the physiological responses in running, in relation to drafting in the cycling sector, according to level and sex. METHODS: To do this, a total of n = 44 subjects were divided into two levels (elite: they got a podium in the national championship, 15.68 ± 0.82 years; amateurs: they compete at the regional level, 15.68 ± 1.62 and 37.9 ± 1.74 years), undergoing two training sessions of four cycling-running multitransitions with variability in the permissibility of drafting were analyzed. A descriptive analysis of the variables was carried out, together with an inferential analysis to know the relationships and associations between the dependent and independent variables. RESULTS: The results showed significant differences in the parameters, as related to running technique, heart rate, speed, and displacement (both between levels and sex). CONCLUSIONS: This study concludes that drafting in the cycling sector generates decisive physiological responses for the running sector.


Asunto(s)
Atletas , Ciclismo , Ciclismo/fisiología , Frecuencia Cardíaca/fisiología , Humanos , Natación/fisiología
10.
J Appl Physiol (1985) ; 133(3): 766-776, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-35834628

RESUMEN

The benefits of drafting for elite marathon runners are intuitive, but the quantitative energetic and time savings are still unclear due to the different methods used for converting aerodynamic drag force reductions to gross metabolic power savings. Further, we lack a mechanistic understanding of the relationship between aerodynamic drag forces and ground reaction forces (GRFs) over a range of running velocities. Here, we quantified how small horizontal impeding forces affect gross metabolic power and GRF over a range of velocities in competitive runners. In three sessions, 12 runners completed six 5-min trials with 5 min of recovery in-between. We tested one velocity per session (12, 14, and 16 km/h), at three horizontal impeding force conditions (0, 4, and 8 N) applied at the waist of the runners. On average, gross metabolic power increased by 6.13% per 1% body weight of horizontal impeding force but the increases varied considerably between individuals (4.17%-8.14%). With greater horizontal impeding force, braking GRF impulses decreased, whereas propulsive GRF impulses increased, but the impulses were not related to individual changes in gross metabolic power. Combining our findings with those of previous aerodynamics studies, we estimate that for a solo runner (52 kg) at 2-h marathon pace, overcoming aerodynamic drag force (1.39% BW) comprises 7.8% of their gross metabolic power and drafting can save between 3 min 42 s and 5 min 29 s.NEW & NOTEWORTHY We measured the metabolic and biomechanical effects of small horizontal impeding forces (representing realistic aerodynamic drag forces) on high-caliber runners across a range of velocities. Combining our metabolic results with existing aerodynamic models indicates that at 2-h marathon pace, optimal drafting likely allows a marathoner to run between 3 min 42 s and 5 min 29 s faster. Our rule-of-thumb (∼6% increase in gross metabolic power per 1% body weight of horizontal impeding force) will allow others to estimate the performance enhancement of different drafting formations.


Asunto(s)
Carrera de Maratón , Carrera , Fenómenos Biomecánicos , Peso Corporal , Metabolismo Energético , Humanos
11.
J Dermatol ; 49(3): e91-e98, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35019155

RESUMEN

Pseudoxanthoma elasticum (PXE) is a progressive hereditary disease that affects tissues such as the skin, retina, blood vessels, and gastrointestinal tracts. Therefore, comprehensive medical care across clinical departments specialized in specific organs is needed to provide the best clinical practices to PXE patients. The Japanese version of clinical guidelines developed by the Japanese Dermatological Association was published in 2017, and aimed to promote equal accessibility of PXE-related medical care. Here, the English version of Japanese guideline is reported, and is intended to be worldwide reference for medical care of PXE.


Asunto(s)
Seudoxantoma Elástico , Humanos , Guías de Práctica Clínica como Asunto , Seudoxantoma Elástico/diagnóstico , Seudoxantoma Elástico/genética , Seudoxantoma Elástico/terapia , Retina , Piel
12.
Adv Mater ; 33(44): e2105011, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34532907

RESUMEN

Oxide crystal ceramics are commonly hard and brittle, when they are bent they typically fracture. Such mechanical response limits the use of these materials in emerging fields like wearable electronics. Here, a polymer-induced assembly strategy is reported to construct orderly assembled TiO2 crystals into continuous nanofibers that are stretchable, bendable, and even knottable. Ball-milling the spinning sol and curved-drafting the electrospun nanofibers significantly improve the molecular structural order and reduce pore defects in the precursor nanofibers. Using this method, continuous TiO2 nanofibers, in which orderly assembled TiO2 nanocrystals (brick) are connected by twin grain boundaries or an amorphous region (mortar), are formed after sintering. Mechanical measurements and finite element analysis simulation indicate that the dislocation slip of "bricks" and the elastic deformation of "mortar" render the nanofibers with a small bending rigidity of ≈22 mN and a small elastic modulus of ≈20.8 Gpa, thus displaying properties associated with both soft and hard matter. More importantly, the reported approach can be easily extended to synthesize a wide range of soft, yet tough ceramic membranes, such as ZrO2 and SiO2 .

13.
BMC Cancer ; 21(1): 488, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33933021

RESUMEN

BACKGROUND: In oncology, Whole Genome Sequencing (WGS) is not yet widely implemented due to uncertainties such as the required infrastructure and expertise, costs and reimbursements, and unknown pan-cancer clinical utility. Therefore, this study aimed to investigate possible future developments facilitating or impeding the use of WGS as a molecular diagnostic in oncology through scenario drafting. METHODS: A four-step process was adopted for scenario drafting. First, the literature was searched for barriers and facilitators related to the implementation of WGS. Second, they were prioritized by international experts, and third, combined into coherent scenarios. Fourth, the scenarios were implemented in an online survey and their likelihood of taking place within 5 years was elicited from another group of experts. Based on the minimum, maximum, and most likely (mode) parameters, individual Program Evaluation and Review Technique (PERT) probability density functions were determined. Subsequently, individual opinions were aggregated by performing unweighted linear pooling, from which summary statistics were extracted and reported. RESULTS: Sixty-two unique barriers and facilitators were extracted from 70 articles. Price, clinical utility, and turnaround time of WGS were ranked as the most important aspects. Nine scenarios were developed and scored on likelihood by 18 experts. The scenario about introducing WGS as a clinical diagnostic with a lower price, shorter turnaround time, and improved degree of actionability, scored the highest likelihood (median: 68.3%). Scenarios with low likelihoods and strong consensus were about better treatment responses to more actionable targets (26.1%), and the effect of centralizing WGS (24.1%). CONCLUSIONS: Based on current expert opinions, the implementation of WGS as a clinical diagnostic in oncology is heavily dependent on the price, clinical utility (both in terms of identifying actionable targets as in adding sufficient value in subsequent treatment), and turnaround time. These aspects and the optimal way of service provision are the main drivers for the implementation of WGS and should be focused on in further research. More knowledge regarding these factors is needed to inform strategic decision making regarding the implementation of WGS, which warrants support from all relevant stakeholders.


Asunto(s)
Consenso , Oncología Médica , Neoplasias/diagnóstico , Secuenciación Completa del Genoma/métodos , Análisis de Datos , Eficiencia , Predicción , Implementación de Plan de Salud , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Neoplasias/genética , Neoplasias/terapia , Reproducibilidad de los Resultados , Encuestas y Cuestionarios , Factores de Tiempo , Incertidumbre , Secuenciación Completa del Genoma/economía , Secuenciación Completa del Genoma/tendencias
14.
J Biomech ; 122: 110457, 2021 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-33933863

RESUMEN

Drafting as a process to reduce drag and to benefit from the presence of other competitors is applied in various sports with several recent examples of competitive running in formations. In this study, the aerodynamics of a realistic model of a female runner is calculated by computational fluid dynamics (CFD) simulations at four running speeds of 15 km h-1, 18 km h-1, 21 km h-1, and 36 km h-1. Aerodynamic power fractions of the total energy expenditure are found to be in the range of 2.6%-8.5%. Additionally, four exemplary formations are analysed with respect to their drafting potential and resulting drag values are compared for the main runner and her pacers. The best of the formations achieves a total drag reduction on the main runner of 75.6%. Moreover, there are large variations in the drag reduction between the considered formations of up to 42% with respect to the baseline single-runner case. We conclude that major drag reduction of more than 70% can already be achieved with fairly simple formations, while certain factors, such as runners on the sides, can have a detrimental effect on drag reduction due to local acceleration of the passing flow. Using an empirical model for mechanical power output during running, gains of metabolic power and performance predictions are evaluated for all considered formations. Improvements in running economy are up to 3.5% for the best formation, leading to velocity gains of 2.3%. This translates to 154 s (≈2.6 min) saved over a marathon distance. Consequently, direct conclusions are drawn from the obtained data for ideal drafting of long-distance running in highly packed formations.


Asunto(s)
Carrera , Femenino , Humanos , Hidrodinámica , Carrera de Maratón
15.
Humanidad. med ; 21(1): 188-208, ene.-abr. 2021. tab
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1250051

RESUMEN

RESUMEN La historia clínica es un documento oficial que exige una redacción rigurosa, pues en ella quedan plasmados datos esenciales del paciente y su padecimiento; así como el tratamiento y las evidencias de su evolución. Debido a lo anterior, es necesario un programa que organice las etapas por las que transita el estudiante para aprender a escribirla. Por ello, el objetivo del presente texto es exponer elementos de un programa que contribuye al desarrollo de habilidades para la redacción de la historia clínica en los estudiantes del tercer año de la carrera Estomatología. Se revisó la literatura científica especializada de cubanos y extranjerosreferida a la temática. Se estudiaron documentos oficiales para conocer los objetivos del modelo del profesional de la carrera Estomatología, así como el programa de la asignatura Propedéutica Clínica y Semiología Estomatológica. Se constataron dificultades en los estudiantes para redactar las historias clínicas y que no existe, al menos en la literatura consultada, un programa que organice las etapas para concretar este proceso. Se propone un programa que brinda orientaciones metodológicas encaminadas a este propósito. El programa permite que los estudiantes sean protagonistas de su proceso de aprendizaje de la redacción de las HC y de su autoevaluación. La investigación constituye una experiencia didáctica puesta en práctica durante el año 2019.


ABSTRACT The clinical history is an official document that requires rigorous drafting, since it contains essential data about the patient and his condition; as well as thetreatment and evidence of his evolution. Due to the above, a program is necessary that organizes the stages the student goes through to learn to write it. Therefore, the objective of this text is to present elements of a program that contributes to the development of skills for the writing of clinical history in students of the third year of the Dentistry career. The specialized scientific literature of Cubans and foreigners on the subject was reviewed. Official documents were studied to know the objectives of the professional model of the Dentistry career, as well as the program of the Clinical Propedeutics and Dentistry Semiology subject. Difficulties were found in the students to write medical records and that there is not, at least in the literature consulted, a program that organizes the stages to specify this process. A program is proposed that provides methodological guidelines for this purpose. The program allows students to be protagonists of their learning process of writing the HC and of theirself-evaluation. There search constitutes a didactic experience put in to practice during the year 2019.

16.
J Biomech ; 107: 109854, 2020 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-32517862

RESUMEN

In this paper we examined the aerodynamic drag and the resulting decrease of power output associated with the drafting positions used by Kenenisa Bekele at the 2019 Berlin marathon. Examination of videos of the race revealed three different positions adopted by Bekele directly behind a frontline of three runners. These drafting positions were numerically studied using CFD simulations performed with the RANS equations and the SST k-ω model. Depending on his position behind the pacers, our analyses indicated that Bekele's drafting strategy resulted in reductions of 38.5-57.3% of the drag resistance and aerodynamic power. In terms of metabolic power, Bekele's drafting positions yielded an estimated 1.91-2.84% reduction compared to the calculated metabolic power of 1427.89 W (or equivalent metabolic power relative to body mass of 25.50 W/kg) that Bekele would have developed if he had run alone at the same speed of 5.75 m.s-1.


Asunto(s)
Carrera de Maratón , Carrera , Berlin , Masculino
17.
Eur J Sport Sci ; 20(6): 831-838, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31526174

RESUMEN

Cycling ergometer protocols are commonly integrated with a virtual reality environment (VRE), especially because of its static position that also allows multiple exercise experiments. Concerning VRE scenarios, visually delayed situations like the ones produced at excessive low update rates can also affect the sense of presence and physiological responses. However, the main interface between the subject and a cycling VRE is the power applied over the crank, and there are only a few experiments to evaluate the effect of delayed situations on this particular interface. Thus, this work aims to investigate the effects of the power update rate (PUR) over the subject`s performance on an avatar-based simulator during a drafting task. A custom cycling VRE was built, and 21 male recreational cyclists (175.9 ± 7.5 cm; 76.5 ± 13.9 kg) were tested at six different PUR levels from 100 to 3000 ms. As a result, PUR affects performance scores (virtual distance, efficiency, and heart rate, p < 0.01) at the given VRE conditions. The case-by-case analysis of the groups reveals that higher update rates always lead to a statistical equivalent or superior performance. Nevertheless, no parameter shows any group difference between 500 ms and lower PUR. These results suggest that virtual cycling protocols should consider PUR and other delay-related mechanisms as possible intervening factors over physiological responses and performance scores.


Asunto(s)
Rendimiento Atlético/fisiología , Ciclismo/fisiología , Ergometría , Realidad Virtual , Retroalimentación Sensorial/fisiología , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Fuerza Muscular/fisiología
18.
Math Biosci Eng ; 17(1): 460-477, 2019 10 14.
Artículo en Inglés | MEDLINE | ID: mdl-31731361

RESUMEN

We study the pedestrian escape from an obscure room using a lattice gas model with two species of particles. One species, called passive, performs a symmetric random walk on the lattice, whereas the second species, called active, is subject to a drift guiding the particles towards the exit. The drift mimics the awareness of some pedestrians of the geometry of the room and of the location of the exit. We provide numerical evidence that, in spite of the hard core interaction between particles-namely, there can be at most one particle of any species per site-adding a fraction of active particles in the system enhances the evacuation rate of all particles from the room. A similar effect is also observed when looking at the outgoing particle flux, when the system is in contact with an external particle reservoir that induces the onset of a steady state. We interpret this phenomenon as a discrete space counterpart of the drafting effect typically observed in a continuum set-up as the aerodynamic drag experienced by pelotons of competing cyclists.

19.
Zhongguo Zhong Yao Za Zhi ; 44(13): 2875-2879, 2019 Jul.
Artículo en Chino | MEDLINE | ID: mdl-31359704

RESUMEN

As a topical plaster developed by modern pharmaceutical technology based on traditional Tibetan medicine,Cheezheng Xiaotong Tiegao has functions of promoting blood circulation,relieving swelling and relieving pain. Since its introduction in 1993,it has been widely used in the treatment of various types of acute and chronic musculoskeletal pain and various types of spinal,joint and soft tissue diseases. In order to better standardize the clinical application and improve the clinical efficacy of Cheezheng Xiaotong Tiegao,the research and development work of the Experts consensus statement on Cheezheng Xiaotong Tiegao in clinical practice was officially launched on October 19,2017,upon approval from China Association of Chinese Medicine. In this paper,main R&D process and related technical links for the experts consensus on Cheezheng Xiaotong Tiegao would be summarized,which will help the various medical workers understand,master and apply more accurately,and also provide reference for the development of experts consensus on clinical application of other topical Chinese medicines.


Asunto(s)
Medicina Tradicional Tibetana , Manejo del Dolor , Administración Tópica , China , Consenso , Humanos , Dolor
20.
J R Soc Interface ; 16(150): 20180768, 2019 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-30958151

RESUMEN

This study focuses on the hydrodynamic interaction between two or three human swimmers in competitive swimming. Although the swimming performance of a single swimmer has been widely examined, studies on the interaction between multiple competitive swimmers are very rare. Experiments showed evidence that the drag of a swimmer could be modified by the existence of the other adjacent competitors (Chatard & Wilson. 2003 Med. Sci. Sports Exerc. 35, 1176-1181. ( doi:10.1249/01.MSS.0000074564.06106.1F )). The following questions arise: (1) what mechanism determines the interaction; (2) which position experiences drag reduction or drag increase; (3) how much can drag be reduced or increased in a formation? According to the authors' knowledge, such questions have not been addressed by any published literature. Therefore, the main purpose of this study is to find the mechanism of the hydrodynamic interaction between human swimmers and to quantify this interactive effect by using a steady potential flow solver. The free-surface effect was fully taken into account in our calculations. We firstly calculated the wave drag of a swimmer swimming solely in an open swimming pool. Then we calculated the wave drag of the same swimmer when he/she swam in the wake region of one or two leading swimmers. The results showed that the hydrodynamic interaction made a significant contribution to the drafter's wave drag. By following a leading swimmer, a drafter at wave-riding positions could save up to 63% of their wave drag at speed of 2.0 m s-1 and lateral separation of 2.0 m. Particularly, when a drafter is following two side-by-side leaders, the drag reduction could even be doubled. To the authors' knowledge, this study is the first to demonstrate that the hydrodynamic interaction between human swimmers can best be described and explained in terms of wave interference effect on the free water surface. When the wave cancellation effect is observed, the wave drag of a drafter could be minimized, and this wave cancellation effect can be achieved only when the drafter is in a wave-riding position.


Asunto(s)
Hidrodinámica , Modelos Biológicos , Natación , Fenómenos Biomecánicos , Femenino , Humanos , Masculino
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