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Journal of Mountain Science 2022年第3期19卷 637-646页

作者： iv novakovskaya EN PATOVA YA DUBROVSKIY AB NOVAKOVSKIY EE KULYUGINA Institute of Biology Komi Scientific CentreUral BranchRussian Academy of SciencesKommunisticheskaya st.28SyktyvkarKomi Republic167982Russia

This paper describes the biodiversity of cyanobacteria and microalgae of biological soil crusts(BSC)on bare substrates in different mountain vegetation types at the Northern *** total,we identified 99 algal species from six divisions in all sampled *** species diversity and structure of BSC algal communities show a relationship with environmental factors(altitude,soil p H and humidity,and illumination).Taxonomic diversity of algae decreases along the altitude gradient from mountain meadow to mountain *** and cyanobacteria species from six divisions were identified in meadow communities,five in mountain forests and four in mountain *** observed a positive correlation between species diversity of phototrophic microorganisms and altitude in the forest communities,but a negative correlation in the *** dominant complex of cyanobacterial and algal species in BSC was specific for each type of plant community and was reflective of the habitat *** species diversity and morphological organization of the BSC algae thalli can be used as a criterion for the ongoing assessment of climatic changes in high latitudes and mountain regions.

关键词： Biological soil crusts Cyanobacteria and microalgae Altitude gradient Northern Urals

Technical efficiency of cocoa farms at varying elevation levels in Davao City, Philippines: implications to sustainable upland farming systems

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Journal of Mountain Science 2024年第1期21卷 33-48页

作者： Francis Levi A.DURANO Jon Marx SARMIENTO Larry N.DIGAL Pedro A.ALVIOLA iv School of Management University of the Philippines MindanaoDavao City 8000Philippines

Elevation is one of many components that influence agriculture, and this in turn affects the level of both inputs and outputs of farmers. This article focuses on the productivity and technical efficiency of 100 cocoa farms using cross-sectional data from areas ranging from 190 to 1021 m above sea level which were classified as low, medium, and high elevation in Davao City, considered as the chocolate capital of the Philippines. Using stochastic frontier analysis, the results showed that the cost of inputs per ha and the number of cocoa trees per ha significantly increase yield. Farms at high elevations were less technically efficient, as this entails lower temperatures and increased rainfall, and cocoa farming in those areas and conditions can be more challenging, especially with changes in farming practices, terrain, and distance to markets. Other significant variables were age of cocoa farms, married farmers, and age of the farmers. Older farms may be more developed, farmers who are married benefit from their spouses being able to readily contribute as farm labor, and lastly, older farmers' inefficiency may likely stem from nonadaptation of newer farming practices. With an average technical efficiency of 0.61, 0.63, and 0.26 in low, medium, and high elevation areas, respectively, farmers therefore have an incentive to improve farm practices and consider topographical variations found in high elevation areas. Recommendations for the improvement of technical efficiency of cocoa farms are better connectivity to markets, enhancing farm practices, and continuation and improvement of government programs on cocoa with an added emphasis on research. For farmers in high elevation areas, mitigating solutions such as sustainable agriculture practices and ecolabelling are key to improving efficiency and minimizing the potential negative impact on upland farming systems. Moreover, such adaptation measures may also contribute to sustainability of cocoa farming in high elevation

关键词： Cocoa farms Cobb-Douglas production function Elevation Philippines Stochastic frontier analysis Technical efficiency

Influence of biomass burning on ozone levels in the Megalopolis of Central Mexico during the COVID-19 lockdown

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Journal of Environmental Sciences 2024年第9期143卷 99-115页

作者： Victor Almanza Luis Gerardo Ruiz-Suárez Ricardo Torres-Jardón Agustín García-Reynoso iván Y.Hernández-Paniagua Institute for Atmospheric Sciences and Climate Change National Autonomous University of MexicoCoyoacan 04510Mexico CityMexico

The massive reductions in anthropogenic emissions resulting from the COVID-19 lockdown provided a unique opportunity to evaluate the effect of mitigation measures aiming to abate air *** Mexico,the total lockdown period took place during the dry-hot season when biomass burning activity is ***,we investigate the role of biomass burning emissions on regional ozone levels in the Megalopolis of Central *** studied period covers the lockdown phases 2 and 3,and the first month of the New *** applied a factor separation technique and process analysis to estimate the pure and synergistic contributions of emission reductions under lockdown and that from biomass burning to daily ozone maximum concentrations in 7 metropolitan areas of different states in the *** results revealed that biomass burning plumes likely masked the effect of massive reductions from mobile emissions,impacted the PBL development during phase 3 and favored transition and mixed NO_(x)-limited and VOC-limited regional *** contributed to increased ozone production in the middle to lower PBL by changing the regional background levels which potentially could bias high ozone production efficiency *** the Megalopolis contribution to economic and societal development at national scale,our study suggests that ozone mitigation measures during the dry-hot season targeting mainly mobile emissions will likely be offset by biomass burning plumes.A regional and synergic policy aiming to control biomass burning would help to reduce the occurrence of high ozone levels in Central Mexico with the co-benefit of tackling short-lived climate pollutants.

关键词： COVID-19 Mexico Megalopolis Ozone Factor Separation Process Analysis

Mental health in organizations from a healthcare analytics framework:taxonomic model,trends,and impact of COVID-19

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Journal of Management Analytics 2024年第1期11卷 62-86页

作者： Jorge iván Pérez Rave Carlos Mario Zapata Jaramillo Gloria Patricia Jaramillo Álvarez IDINNOV research group IDINNOV S.A.SMedellínColombia Department of Computing and Decision Sciences Universidad Nacional de ColombiaMedellínColombia

Mental disorders negatively affect employee well-being and organizational *** face a challenge in terms of how to manage mental *** paper clarifies three issues(underlying patterns,trends,and impact of COVID-19)regarding the scientific study of mental health in organizations from a healthcare analytics *** framework comprises eight stages considering a text-driven approach with scientific corpora assisted by linguistic/computational and statistical *** study discovers a new taxonomic model comprising five patterns in the scientific discourse on the *** analyses reveal imbalances and concerns regarding the interests associated with the patterns,which is reinforced by examining patterns“before”and“during”*** paper complements psychological/epidemiological studies on mental health in organizations from a healthcare analytics perspective.

关键词： Healthcare analytics healthcare management analytics mental health scientific discourse text analytics taxonomy COVID-19 management analytics

极干旱胁迫对雀麦、多年生黑麦草生长和体内水分的影响

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草地学报 2024年

作者：张咏梅胡海英白小明 Matthew Cory García-Favre Javier Ordó?ez iván P 甘肃农业大学干旱生境作物学国家重点实验室宁夏大学林业与草业学院甘肃农业大学草业学院农业与环境学院梅西大学坎佩奈克农艺研究所

为研究极端干旱对牧草生长的影响，选择多年生黑麦草（Lolium Perenne）(Lp)和雀麦（Bromus Valdivianus）(Bv)给予80%?85%植物有效水（Plant available water， PAW）和20%?25% PAW 2种水分处理，分析2牧草生长及体内水分状况对干旱胁... 详细信息

为研究极端干旱对牧草生长的影响，选择多年生黑麦草（Lolium Perenne）(Lp)和雀麦（Bromus Valdivianus）(Bv)给予80%?85%植物有效水（Plant available water， PAW）和20%?25% PAW 2种水分处理，分析2牧草生长及体内水分状况对干旱胁迫的响应。研究表明：1)80%?85% PAW充足水分下，2牧草生物量积累、水势（Water potential， WP）、相对含水量（Relative water content， RWC）和净光合速率（Net photosynthetic rate， Pn）无明显种间差异。Bv叶片宽而重、蒸腾速率（Transpiration rate， Tr）、CO2总导度(Total conductance to CO2， CndCO2)和气孔导度(Conductance to H2O， Gs)显著高于Lp。而Lp分蘗多、叶多汁；瞬时水分利用效率是Bv的1.63倍。2)20%?25% PAW对2牧草生长影响不完全一致，叶饱和重、干重和叶面积有相反变化趋势，但与充足水分相比差异不显著；Pn，Tr，CndCO2，Gs和RWC则极显著降低，WP极显著降低了1.60 MPa，致使枯叶占比和叶温差的显著升高。总之，雀麦和多年生黑麦草生长相近，水分利用模式不同；遭受极端干旱，不同种的2牧草耐旱机制具有一定的共性，通过增强叶片持水力、降低水分循环、减少蒸腾失水以提高牧草抗旱性。

关键词：干旱胁迫光合作用蒸腾作用生物量积累瞬时水分利用效率水势

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休闲食品行业可持续消费的商业模式创新研究

中国食品 2024年第16期 126-128页

作者：阳欢 Jaime T.Ballena iv 菲律宾圣路易斯大学

随着社会的进步和消费者环保意识的增强,可持续消费已逐渐成为休闲食品行业的重要发展方向。休闲食品行业可持续消费的商业模式创新不仅有助于提升企业的社会形象,开发出更符合市场需求的产品,提高品牌忠诚度,进而增加市场份额和销售额... 详细信息

随着社会的进步和消费者环保意识的增强,可持续消费已逐渐成为休闲食品行业的重要发展方向。休闲食品行业可持续消费的商业模式创新不仅有助于提升企业的社会形象,开发出更符合市场需求的产品,提高品牌忠诚度,进而增加市场份额和销售额,还有助于减少对环境的负面影响,引导整个行业朝着更加健康、环保和可持续的方向发展,推动整个行业的进步。为此,本文分析了休闲食品行业的现状及发展趋势,阐述了可持续消费的重要性和紧迫性,并从产品创新、销售模式创新、供应链创新和品牌形象创新等方面,详细论述了休闲食品行业如何通过商业模式创新实现可持续消费,从而促进经济、环境和社会效益的和谐统一。

关键词：商业模式创新品牌忠诚度休闲食品行业符合市场需求可持续消费供应链创新和谐统一品牌形象

Standardizing MI-TLIF, a Proposal for a Reproducible Technique

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Open Journal of Modern Neurosurgery 2024年第2期14卷 91-103页

作者： iván Ulises Sámano López Jesús Alberto Pérez Contreras Emmanuel Cantú Chávez Diana Chávez Lizárraga Ana Sofía Peña Blesa Thania Karina Gutiérrez Anchondo Á ngeles Pedregal Ciudad de México México

Background: Minimally invasive transforaminal lumbar interbody fusion (MI TLIF) is a widely known and performed technique, however its versatility among different physicians continues to hinder its replication and results. Therefore, this study aimed to provide a step-by-step surgical guide to perform a safe MI-TLIF, based on the results obtained in patients operated on by a single surgeon over a period of 12 years. Patients and methods: A retrospective, single center, longitudinal, and observational cohort study was conducted with 931 patients who underwent MI TLIF by a single surgeon between 2010 and 2022 using the technique described on this paper, each with a minimum follow-up of 12 months. Criteria included Schizas classification, listhesis according to Meyerding classification, number of levels treated, cage size, and complications (screw repositioning or cerebrospinal fluid leak). Patient clinical outcomes were assessed using the Oswestry Disability Index (ODI), Visual Analog Scale (VAS) for pre- and postoperative radicular pain. Thin slice CT scans were used to assess the progression of the fusion using the Bridwell classification. In the statistical analysis, percentages, median, and interquartile range (IQR) were calculated. Results: Nine hundred and thirty one patients underwent MI TLIF using the technique described, eight hundred and eighty (94.5%) had a single level treated and fifty one (5.5%) had a 2 level procedure (982 levels), an 8mm cage was placed on five hundred and seventeenlevels (52.7%), six hundred and sixty three levels(67.6%) achieved grade I fusion, two hundred and sixty six levels (27.1%) achieved grade II fusion, 52 levels (5.3) achieved grade III fusion and one level (0.1) achieved a grade iv fusion or non-union. Revision surgery was performed on 3 patients (0.3%) for screw repositioning, cerebrospinal fluid leak was present on 2 patients during surgery and treated before closure. VAS scores and ODI were improved at 12 months postop (V

关键词： MITLIF Lumbar Interbody Fusion Technique Pain Relief and Disability

Academic Stress Assessment Using Virtual Reality as an Educational Tool in Spine Surgery

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Open Journal of Modern Neurosurgery 2024年第2期14卷 114-123页

作者： Diana Chávez Lizárraga Jesús Alberto Pérez Contreras Fernando Alvarado Gómez Evelyn Quintero Medina Emmanuel Cantú Chávez iván Ulises Sámano López Ana Sofía Peña Blesa Department of Neurosurgery ángeles Pedregal Ciudad de México México Department of Traumatology and Orthopedics Hospital Santa Fe Bogotá Colombia

Introduction: The evaluation of academic stress in medical students and residents is a topic of significant interest, given the considerable challenges they face during their learning process with traditional teaching methods. The use of technologies like virtual reality presents an opportunity to enhance their skills through simulations and training. The main objective of this study is to qualitatively assess the stress levels experienced by medical students and residents by integrating virtual reality into their current learning methods, aiming to improve their ability to manage stressors in their practice. Material and Methods: A questionnaire was conducted with 12 medical students and 12 Traumatology and orthopedics residents. The purpose of the questionnaire was to evaluate the levels of academic stress using the SISCO inventory. The stress levels were calculated by transforming average values into percentages, and the following criteria were assigned: 0 to 33% for Mild Stress, 34 to 66% for Moderate Stress, and 67 to 100% for Deep Stress. Then, a virtual reality class focused on spine surgery was provided. Both medical students and residents were trained using the Non Nocere SharpSurgeon software platform and Oculus Quest 2 virtual reality glasses. At the end of the session, a second questionnaire related to the practice with virtual reality was conducted with the same evaluation criteria and a comparative analysis was carried out. Results: 12 undergraduate students from Hospital Angeles Mexico, CDMX and 12 traumatology and orthopedics residents at Hospital Santa Fe, Bogota were evaluated. The students in CDMX reported an average qualitative stress of 28.50% during habitual practices, which decreased to an average of 14.67% after virtual reality practice. Residents in Bogotá experienced an average qualitative stress of 30.50% with their current learning methods but this reduced to an average of 13.92% after using virtual reality. These findings indicate that t

关键词： Virtual Reality Academic Stress Learning Strategies Spine Surgery Training

NO-ARBITRAGE SYMMETRIES

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Acta Mathematica Scientia 2022年第4期42卷 1373-1402页

作者： iván DEGANO Sebastián FERRANDO Alfredo GONZáLEZ Departamento de Matemática.Facultad de Ciencias Exactas y Naturales Universidad Nacional de Mar del Plata 7600Argentina Department of Mathematics Ryerson University350 Victoria St.TorontoOntario M5B 2K3Canada

The no-arbitrage property is widely accepted to be a centerpiece of modern financial mathematics and could be considered to be a financial law applicable to a large class of(idealized) *** paper addresses the following basic question:can one characterize the class of transformations that leave the law of no-arbitrage invariant?We provide a geometric formalization of this question in a non probabilistic setting of discrete time-the so-called trajectorial *** paper then characterizes,in a local sense,the no-arbitrage symmetries and illustrates their meaning with a detailed *** context makes the result available to the stochastic setting as a special case.

关键词： No arbitrage symmetry convexity preserving maps non-probabilistic markets

Effects of Added Mass on Muscle Activity and Joint Movement During Walking

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Journal of Bionic Engineering 2023年第6期20卷 2703-2715页

作者： Yali Han Frank C.Sup iv Ziyang Han Zhangzhang Mi Department of Mechanical Engineering Nanjing Institute of TechnologyNanjing211167China Department of Mechanical and Industrial Engineering University of MassachusettsAmherstMA01003USA

Added mass provided irregular interference towards human movement and shifted the force generated by lower limb ***,the association between mass and muscle activities is not well *** study aims at investigating the influence of added mass on lower *** our study,five young,healthy walkers performed walking trials under three load conditions(unload;C1:0.25 pounds on feet,1 pound on calves,and 2 pounds on thighs;C2:1 pound on feet,2 pounds on calves,and 4 pounds on thighs).During walking,three-dimensional kinematics,sEMG signals,and oxygen consumption were collected which allowed us to understand the effects of added mass on *** also generated OpenSim simulation,designed to comprehend the relationship between added mass and *** the increase of added mass,maximum sEMG signal and peak joint torque increased;whereas,the horizontal stride time reduced(unload:1.697±0.02 s,C1:1.651±0.02 s,C2:1.622±0.02 s).Energy expenditure raised correspondingly(C1:6.53%,C2:24.85%).Moreover,joint moment increased,while same change occurred in muscle ***,our results show that participants responded positively to additional mass by adjusting muscle activities,joint movement,and stride frequency,which demonstrates the relationship between energy consumption and added mass.

关键词： Biomechanics Load carriage Gait Muscle force