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Effects of micro-environmental conditions and forest disturbance on the establishment of two Andean palms in Ecuador

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Open Journal of Ecology 2012年第4期2卷 233-243页

作者： Diana Rodríguez-Paredes rommel montúfar-galárraga Henrik Meilby Ecology and Genetics Pontificia Universidad Católica del Ecuador Quito Ecuador Forest & Landscape University of Copenhagen Copenhagen Denmark

The wax palm (Ceroxylon echinulatum) and palm heart (Prestoea acuminata) are key elements in Andean natural forests. This ecosystem is threatened by deforestation and habitat degradation, thus, it is vital to explore the impact of anthropogenic activities on the ecological structure and preferences of these species in order to develop proper conservation strategies. Fifty-seven 400 m2 plots were established in two forest areas, a disturbed forest (n = 30 plots) and an undisturbed forest (n = 27 plots) in the Ecuadorean Andes. Nine micro-environmental variables and the number of individuals of C. echinulatum and P. acuminata in five size classes were recorded in each plot. Logistic regression models helped identify environmental variables that influence the establishment of the species. Results showed that different micro-environmental variables determined the presence of different size classes. Both species were benefitted by the environmental conditions of the disturbed forest. Light availability was important for the establishment of both species, especially for the canopy species (C. echinulatum). This palm was negatively affected by the variable “fallen wood”, while P. acuminata was negatively affected mainly by the steepness of the terrain. The environmental variables for the successful establishment of the studied species that were identified by this study provide clues for the sustainable management of C. echinulatum and P. acuminata in Andean forests.

关键词： Andean Forest Ceroxylon Forest Disturbance Micro-Environmental Variables Palm Establishment Prestoea Sustainable Management

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Recent advances and future therapy development for Alzheimer’s disease and related disorders

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Neural Regeneration Research 2024年第9期19卷 1877-1878页

作者： Megan Hong gal Bitan Department of Neurology David Geffen School of MedicineUniversity of California Los AngelesLos AngelesCAUSA Department of Chemistry and Biochemistry University of California Los AngelesLos AngelesCAUSA Molecular Biology Institute University of California Los AngelesLos AngelesCAUSA Brain Research Institute University of CaliforniaLos AngelesCAUSA

Over 55 million people globally live with Alzheimer’s disease(AD)or related dementias(ADRD)and the number is expected to double every twenty *** i l recent l y,onl y symptomatic treatments were available to patients with AD,including acetylcholine esterase inhibitors,of which the last one,galantamine,was approved by the US Food and Drug Administration(FDA)in 2001.

关键词： Alzheimer globally patients

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Intraspecific scaling and early life history determine the cost of free-flight in a large beetle(Batocera rufomaculata)

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Insect Science 2024年第2期31卷 524-532页

作者： Tomer Urcai Eran Levin Eran Gefen gal Ribak Faculty of Life Sciences School of ZoologyTel Aviv UniversityTel AvivIsrael Steinhardt Museum of Natural History Israel National Center for Biodiversity StudiesTel AvivIsrael Department of Biology University of Haifa-OranimKiryat TivonIsrael

The scaling of the energetic cost of locomotion with body mass is well documented at the interspecific ***,methodological restrictions limit our understanding of the scaling of flight metabolic rate(MR)in free-flying *** is particularly true at the intraspecific level,where variation in body mass and flight energetics may have direct consequences for the fitness of an *** applied a 13C stable isotope method to investigate the scaling of MR with body mass during free-flight in the beetle Batocera *** species exhibits large intraspecific variation in adult body mass as a consequence of the environmental conditions during larval *** show that the flight-MR scales with body mass to the power of 0.57,with smaller conspecifics possessing up to 2.3 fold higher mass-specific flight MR than larger *** the scaling exponent of free-flight MR was found to be like that determined for tethered-flight,the energy expenditure during free-flight was more than 2.7 fold higher than for *** metabolic cost of flight should therefore be studied under free-flight conditions,a requirement now enabled by the 13C technique described herein for insect flight.

关键词： allometry body mass Coleoptera free-flight insect flight stable carbon isotope tethered-flight

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Influence of cerium ions on structure-dependent magnetic properties of Ba-Sr M-type hexaferrite nanocrystals

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Journal of Rare Earths 2024年第2期42卷 364-372,I0005页

作者： Ram A.Pawar Sunil M.Patange P.M.Dighe Sher Singh Meena Abdullah gal-Sehemi Mehboobali Pannipara Santosh S.Jadhav Department of Physics ArtsCommerce and Science CollegeAhmednagar413711MaharashtraIndia Department of Physics Shri Krishna MahavidyalayaGunjotiDistOsmanabad413606MaharashtraIndia Padmashri Vikhe Patil College of Arts Science and CommercePravaranagarA/P.Loni(Kd)Tal.RahataDistAhmednagar413713MaharashtraIndia Solid State Physics Division Bhabha Atomic Research CentreMumbai400085MaharashtraIndia Department of Chemistry King Khalid UniversityAbha61413Saudi Arabia Department of Physics D.S.M's ArtsCommerce and Science CollegeJintur431509MaharashtraIndia

The present study is a systematic effort to investigate the structure-sensitive magnetic parameters of Ce^(3+) substituted Ba-Sr hexaferrite nanocrystals chemically formulated as Ba_(0.5)Sr_(0.5)Ce_(x)Fe_(12-x)O_(19) where x=0.0-0.2 with Δx=*** hexaferrite powders were prepared using the sol-gel self-ignition route and structurally characterized by means of powder X-ray diffraction and Fourier transform infrared *** creation of the M-type hexaferrite phase within the synthesized samples was revealed from the Rietveld refinement of the X-ray *** occurrence of a secondary phase of CeO_(2) was revealed within the hexaferrites for the substitution,x> *** refined X-ray diffraction data were utilized to compute the lattice parameters,X-ray density,and lattice parameter *** crystal structure plotted from the refined XRD data reveals the occupancy of the ions at different lattice *** XPS data of the hexaferrite were analyzed to confirm the oxidation states of the constituent *** nanocrystalline nature of the hexaferrites was revealed from the crystallite sizes calculated using Scherer's *** analysis of FTIR spectra confirms that only a fraction of Ce^(3+)accommodated in the lattice and the remaining Ce content reside in the form of the CeO_(2) *** morphology of the hexaferrites was analyzed from the FESEM profiles of the ferrite *** magnetic behavior study was performed by analyzing the Curie temperature,hysteresis loops,and hyperfine interactions by means of susceptibility,V.S.M,and Mossbauer spectroscopy,*** hexaferrites with increasing coercivity,decreasing saturation magnetization,and decreasing Curie temperature are reported in the *** substituted Ce^(3+)ions inhibit the grain growth and create lattice imperfections giving rise to hexaferrites with tuned magnetic parameters suitable for different applications.

关键词： Ba-Sr hexaferrite Ce^(3+)substitution XPS Saturation magnetization Coercivity M?ssbauer spectroscopy

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Metastatic pancreatic and lung cancer patient in complete remission following immunotherapy: A case report and review of literature

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 2233-2240页

作者： Joaquina Martínez-galán Cristina Jiménez-Luna Isabel Rodriguez Elisabeth Maza Carlos García-Collado Antonio Rodríguez-Fernández Javier Luis López-Hidalgo Octavio Caba Department of Medical Oncology Virgen de las Nieves University HospitalGranada 18014Spain Instituto de Investigación Biosanitaria Ibs.GranadaGranada 18012Spain Institute of Biopathology and Regenerative Medicine(IBIMER) University of GranadaGranada 18016Spain Pharmacogenetics Unit Virgen de las Nieves University HospitalGranada 18014Spain Department of Medicina Nuclear Virgen de las Nieves University HospitalGranada 18014Spain Department of Anatomía Patológica Virgen de las Nieves University HospitalGranada 18014Spain

BACKGROUND Metastatic pancreatic ductal adenocarcinoma(PDAC)is a lethal malignancy with dispiriting survival *** is a promising approach to many cancer types,but achieves poor outcomes in advanced PDAC due to its immunosuppressive tumor *** describe a case of metastatic PDAC effectively treated with *** SUMMARY We report the case of a 67-year-old woman with unresectable locally advanced PDAC,treated with gemcitabine plus nab-paclitaxel followed by radiotherapy plus *** nine months,pancreatic tumor progression was observed at the level of the hepatic hilum with the appearance of a new pulmonary nodule suggestive of a second primary,confirmed by left lung *** immunotherapy was then initiated with pembrolizumab,an immune checkpoint inhibitor targeting programmed cell death protein-1 that covers the two tumor *** patient showed a complete metabolic response that was maintained throughout the *** patient continues to be disease-free at 5.6 years since the start of *** These results suggest that the administration of pembrolizumab after chemoradiotherapy has a beneficial effect in patients with metastatic *** our knowledge,this is the first reported case of a patient with metastatic PDAC and metastatic lung cancer showing such a long-lasting complete response after pembrolizumab treatment without curative *** studies are required to determine biomarkers that identify PDAC patients most likely to benefit from this immunotherapy.

关键词： Pancreatic ductal adenocarcinoma Lung cancer Immunotherapy Pembrolizumab Programmed cell death protein-1 Case report

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Lab results of COVID-19 patients:Omicron vs delta variants

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World Journal of Virology 2024年第2期13卷 71-77页

作者： Dana Avraham Amir Herman gal Shaham Arkady Shklyar Elina Sulim Maria Oulianski Orthopedic Department Kaplan Medical CenterRehovot 7661041Israel Department of Medicine Lithuanian University of Health SciencesKaunas 44307Lithuania Emergency Department Kaplan Medical CenterRehovot 7661041Israel

BACKGROUND The coronavirus disease 2019(COVID-19)virus has been a world-known pan-demic since February *** variances had been established;the most common variants in Israel were omicron and *** To analyze and compare laboratory values in the"omicron"and"delta"variants of the coronavirus by conducting follow-up examinations and laboratory audits on COVID-19 patients admitted to our *** A retrospective study,two groups,50 patients in each *** examined positive for COVID-19 were divided into groups according to the common variant at the given *** reviewed demographic data and laboratory results such as complete blood count and full chemistry,including electrolytes and coagulation *** The mean age was 52%,66.53±21.7 were *** significance was found comparing laboratory results in the following disciplines:Blood count,hemo-globin,and lymphocytes(P=0.41,P=0.87,P=0.97).Omicron and delta variants have higher neutrophil counts,though they are not significantly different(P=0.38).Coagulation tests:Activated paritial thromoplastin test and international normalized ratio(P=0.72,P=0.68).We found no significance of abnormality for all *** The study compares laboratory results of blood tests between two variants of the COVID-19 virus–omicron and *** found no significance between the *** results show the need for further research with larger data as well as the need to compare all COVID-19 variants.

关键词： COVID-19 Coronavirus Omicron variant Delta variant

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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

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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

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Cellular automata model for traffic flow with safe driving conditions

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Chinese Physics B 2014年第5期23卷 216-226页

作者： María Elena Lárraga Luis Alvarez-Icaza Instituto de Ingeniería Universidad Nacional Autónoma de México04510Coyoacán D.F.México

In this paper, a recently introduced cellular automata （CA） model is used for a statistical analysis of the inner micro-scopic structure of synchronized traffic flow. The analysis focuses on the formation and dissolution of clusters or platoons of vehicles, as the mechanism that causes the presence of this synchronized traffic state with a high flow. This platoon formation is one of the most interesting phenomena observed in traffic flows and plays an important role both in manual and automated highway systems （AHS）. Simulation results, obtained from a single-lane system under periodic boundary conditions indicate that in the density region where the synchronized state is observed, most vehicles travel together in pla- toons with approximately the same speed and small spatial distances. The examination of velocity variations and individual vehicle gaps shows that the flow corresponding to the synchronized state is stable, safe and highly correlated. Moreover, results indicate that the observed platoon formation in real traffic is reproduced in simulations by the relation between vehicle headway and velocity that is embedded in the dynamics definition of the CA model.

关键词： traffic flow models synchronized traffic cellular automata platoons formation

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Significance of using isolated footing technique for resi- dential construction on expansive soils

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Frontiers of Structural and Civil Engineering 2017年第1期11卷 123-129页

作者： Harry far Deacon FLINT Centre for Built Infrastructure Research School of Civil and Environmental Engineering University of Technology Sydney (UTS)Australia

Expansive soils cause problems with the founding of lightly loaded structures in many parts of the world. Foundation design for expansive soils is one of the most discussed and problematic issues in Australia as expansive soils were responsible for billions of dollars＇ worth of damage to man-made structures such as buildings and roads. Several studies and reports indicate that one of the most common and least recognized problems causing severe structural damage to houses lies in expansive soils. In this study, a critical review has been carried out on the current Australian standards for building on expansive soils and they are compared with some techniques that are not included in the current Australian standards for residential slabs and footings. Based on the results of this review, the most effective and economical method has been proposed for construction of footings on all site classifications without restriction to 75mm of characteristic movement. In addition, it has become apparent that as design procedures for footings resting on sites with extreme characteristic movements are not included in the current Australian standards, there is a strong need for well-developed and simplified standard design procedures for characteristic soil movement of greater than 75mm to be included into the Australian Standards.

关键词： expansive soils residential slabs isolated footings Australian Standards

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