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A Novel Derivation of Black Hole entropy in all Dimensions from Truly Point Mass Sources

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Journal of High energy Physics, Gravitation and cosmology 2024年第3期10卷 1017-1028页

作者： carlos castro Perelman Bahamas Advanced Science Institute and conferences Ocean Heights Stella Maris Long Island Bahamas Ronin Institute Haddon Place Montclair USA

It is explicitly shown how the Schwarzschild Black Hole entropy (in all dimensions) emerges from truly point mass sources at r=0due to a non-vanishing scalar curvature involving the Dirac delta distribution. In order to achieve this, one is required to extend the domain of r to negative values −∞≤r≤+∞. It is the density and anisotropic pressure components associated with the point mass delta function source at the origin r=0which furnish the Schwarzschild black hole entropy in all dimensions D≥4after evaluating the euclidean einstein-Hilbert action. Two of the most salient results are i) that the observed spacetime dimension D=4is precisely singled out from all the other dimensions when the strong and weak energy conditions are met, and ii) the point mass source described in this work is not the result of a spherically symmetric gravitational collapse of a star as described by the Oppenheimer-Snyder model because we are not neglecting the pressure. As usual, it is required to take the inverse Hawking temperature βHas the length of the circle Sβ1obtained from a compactification of the euclidean time in thermal field theory which results after a Wick rotation, it=τ, to imaginary time. This approach can be generalized to the Reissner-Nordstrom and Kerr-Newman metrics. The physical implications of this finding warrant further investigation since it suggests a profound connection between the notion of gravitational entropy and spacetime singularities.

关键词： General Relativity Black Holes entropy Strings

Mixed neuroendocrine non-neuroendocrine neoplasms in gastroenteropancreatic tract

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1166-1179页

作者： Sebastián Díaz-López Jerónimo Jiménez-castro carlos enrique Robles-Barraza carlos Ayala-de Miguel Manuel chaves-conde Medical Oncology Department Hospital Universitario ValmeSeville 41014AndalucíaSpain

Mixed neuroendocrine non-neuroendocrine neoplasms(MiNeNs)are a hetero-geneous group of malignant neoplasms that can settle in the gastroenteropan-creatic *** are composed of a neuroendocrine(Ne)and a non-Ne compo-nent in at least 30%of each *** non-Ne component can include different histological combinations of glandular,squamous,mucinous and sarcomatoid phenotypes,and one or both of the components can be low-or high grade *** changes in the nomenclature of these neoplasms might lead to great deal of confusion,and the lack of specific clinical trials is the main reason why their management is *** review aims to clarify the definition of MiNeN and analyze available evidence about their diagnosis and treatment options according to their location and extension through careful analysis of the available *** would be important to reach a general consensus on their diagnosis in order to construct a classification that remains stable over time and facilitates the design of clinical trials that,due to their low incidence,will require long recruitment periods.

关键词： Mixed neuroendocrine non-neuroendocrine neoplasms Mixed adenoneuroendocrine carcinomas Mixed tumours Gastroenteropancreatic Treatment etiology Diagnosis

Low-cost,simple,and scalable self-assembly of DNA origami nanostructures

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Nano Research 2019年第5期12卷 1207-1215页

作者： Patrick D.Halley Randy A.Patton Amjad chowdhury john c.byrd.carlos e.castro Department of chemical and Biomolecular engineering The Ohio State UniversityColumbusOH 43210USA Department of Mechanical and Aerospace engineering The Ohio State UniversityColumbusOH 43210USA Division of Hematology Department of Internal Medicineand OSU Comprehensive Cancer CenterThe Ohio State UniversityColumbusOH 43210USA Biophysics Graduate Program The Ohio State UniversityColumbusOH 43210USA

Despite demonstrating exciting potential for applications such as drug delivery and biosensing,the development of nanodevices for practical applications and broader use in research and education are still hindered by the time,effort,and cost associated with DNA origami *** and robust methods to perform and scale the DNA origami self-assembly process are critical to facilitate broader use and translation to industrial or clinical *** report a simple approach to fold DNA origami nanostructures that is fast,robust,and *** demonstrate fabrication at scales approximately 100-1,500-fold higher than typical *** further demonstrate an approach we termed low-cost efficient annealing (LeAN) self-assembly involving initial heating at 65 ℃ for 10 min,then annealing at 51 ℃ for 2 h,followed by brief quenching at 4 ℃ that leads to effective assembly of a range of DNA origami structures *** contrast to other methods for scaling DNA origami assembly,this approach can be carried out using cheap and widely available equipment (e.g.,hot plates,water baths,and laboratory burners) and uses standard recipes and materials so is readily applied to any existing or new DNA origami *** envision these methods can facilitate device development for commercial applications and facilitate broader use of DNA origami in research and education.

关键词： DNA origami DNA nanotechnology self assembly scalable nanofabrication low cost fabrication nanotechnology education

Mortality rate after total knee arthroplasty or total hip arthroplasty in patients with a history of liver transplant

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World Journal of Orthopedics 2024年第4期15卷 310-311页

作者： e carlos Rodriguez-Merchan Department of Orthopedic Surgery La Paz University Hospital-IdiPazMadrid 28046Spain

In this editorial I comment on the article by Ahmed et al published in a recent issue of the World J Orthop 2023;14:*** is well known that patients who have undergone a liver transplant(LT)may need to have a total hip arthroplasty(THA)or total knee arthroplasty(TKA)*** et al stated that the mortality rate in these patients was similar to the one of the general ***,there are three articles previously published that found higher mortality in LT patients who experienced THA/TKA than in the general population(individuals without LT).Therefore,in this editorial I would like to point out that there is controversy in the literature regarding whether LT patients undergoing THA/TKA have higher mortality than the general ***,future research should attempt to resolve this controversy.

关键词： Liver transplant Total knee arthroplasty Total hip arthroplasty Results Mortality

Review of Networked Microgrid Protection:Architectures,challenges,Solutions,and Future Trends

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cSee Journal of Power and energy Systems 2024年第2期10卷 448-467页

作者： Jorge de la cruz Ying Wu john e.candelo-Becerra Juan c.Vasquez Josep M.Guerrero center for Research on Microgrids(cROM) Department of Energy TechnologyAalborg University9220 AalborgDenmark Facultad de Minas Departamento de Energia Eléctrica y AutomaticaUniversidad Nacional de ColombiaSede MedellinCarrera 80 No.65-223RobledoMedellin 050041Colombia. center for Research on Microgrids at UPc(UPc cROM) Department of Electronic EngineeringTechnical University of Catalonia(UPC)08019 Barcelona Spain IcReA Pg.Lluis Companys 2308010 BarcelonaSpain center for Research on Microgrids at AAU(AAU cROM) AAU EnergyAalborg University(AAU)9220 Aalborg EastDenmark

Design and selection of advanced protection schemes have become essential for reliable and secure operation of networked *** protection schemes that allow correct operation of microgrids have been proposed for individual systems in different topologies and ***,protection schemes for networked microgrids are still in devel-opment,and further research is required to design and operate advanced protection in interconnected *** of these microgrids in different nodes with various intercon-nection technologies increases fault occurrence and complicates protection *** paper aims to point out challenges in developing protection for networked microgrids,potential solutions,and research areas that need to be addressed for their ***,this article presents a systematic analysis of different microgrid clusters proposed since 2016,including several architectures of networked microgrids,operation modes,components,and utilization of renewable sources,which have not been widely explored in previous review ***,the paper presents a discussion on protection systems currently available for microgrid clusters,current challenges,and solutions that have been proposed for these ***,it discusses the trend of protection schemes in networked microgrids and presents some conclusions related to ***—Adaptive eprotection,microgrid cluster,microgrid,multiple microgrid,networked microgrid,real-time simulation,smart grid.

关键词： Adaptive eprotection microgrid cluster microgrid multiple microgrid networked microgrid real-time simulation smart grid

How to fill the biodiversity data gap:Is it better to invest in fieldwork or curation?

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Plant Diversity 2024年第1期46卷 39-48页

作者： carlos A.Vargas Marius Bottin Tiina Sarkinen James e.Richardson Marcela celis Boris Villanueva Adriana Sanchez Programa de Biología Facultad de Ciencias NaturalesUniversidad del RosarioBogotaD.C.Colombia Subdireccion científica Jardín Botanico de Bogota“Jose Celestino Mutis”BogotaD.C.Colombia Independent Researcher BogotaD.C.Colombia Tropical Diversity Section Royal Botanic Garden EdinburghUK School of Biological Earth and Environmental SciencesUniversity College CorkCorkIreland Departamento de Química y Biología Universidad del NorteKm.5 Vía Puerto ColombiaArea Metropolitana de Barranquilla 081007Colombia

Data gaps and biases are two important issues that affect the quality of biodiversity information and downstream *** how best to fill existing gaps and account for biases is necessary to improve our current information most *** current main approaches for obtaining and improving data include(1)curation of biological collections,and(2)***,the comparative effectiveness of these approaches in improving biodiversity data remains little *** used the Flora de Bogota project to study the magnitude of change in species richness,spatial coverage,and sample coverage of plant records based on curation versus *** process of curation resulted in a decrease in species richness(synonym and error removal),but it significantly increased the number of records per *** contributed to a slight increase in species richness,via accumulation of new ***,curation led to increases in spatial coverage,species observed by locality,the number of plant records by species,and localities by species compared to ***,curationwas more efficient in producing new information compared to fieldwork,mainly because of the large number of records available in *** recommend intensive curatorial work as the first step in increasing biodiversity data quality and quantity,to identify bias and gaps at the regional scale that can then be targeted with *** stepwise strategy would enable fieldwork to be planned more costeffectively given the limited resources for biodiversity exploration and characterization.

关键词： colombia Flora de Bogota Sample coverage Species richness Tropical Andes

New pharmacological tools:the use of diterpenes to promote adult hippocampal neurogenesis

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Neural Regeneration Research 2024年第8期19卷 1629-1630页

作者： Ricardo Gomez-Oliva Pedro Nunez-Abades carmen castro Department of Biomedicine Biotechnology and Public HealthDivision of PhysiologyUniversity of CadizCadizSpain Biomedical Research and Innovation Institute of cadiz(INiBIcA) CadizSpain Department of Physiology University of SevilleSevilleSpain

Tissue regeneration maintains homeostasis and preserves the functional features of each ***,not all tissues show a strong repairing *** is the case of the central nervous *** is now well established that the generation of new functional neurons from stem cells in the adult brain occurs in specific regions of the brain of different species such as rodents,birds,primates,and humans(eriksson et al.,1998).

关键词： capacity maintain preserve

Targeting epidermal growth factor receptor signaling to facilitate cortical injury repair?

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Neural Regeneration Research 2024年第5期19卷 935-936页

作者： Ricardo Gómez-Oliva Pedro Nunez-Abades carmen castro Área de Fisiología Facultad de Medicina Universidad de CádizCadizSpain Instituto de Investigación e Innovación en Biomedicina de cádiz CadizSpain Departamento de Fisiología Facultad de FarmaciaUniversidad de SevillaSevilleSpain

The existence of neural stem cells(NSc)in specific areas of the adult mammalian brain leads to the generation of new neurons involved in homeostatic *** is the case of the NSc of the subventricular zone(SVZ)that produces olfactory bulb(OB)*** neurons integrate into circuits to modulate sensory information and participate in olfactory processing(Bragado Alonso et al.,2019).A series of hierarchical events need to take place to produce OB neurons from NSc of the ***,the activation of quiescent NSc is necessary to produce intermediate transit amplifying progenitors(TAP),which will generate *** latter are cells that maintain a proliferative phenotype while in an immature ***,once they initiate migration toward the OB,they progressively undergo their differentiation into neurons(Kjell et al.,2020).

关键词： ventricular maintain

Immunotherapy of gastric cancer:Present status and future perspectives

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World Journal of Gastroenterology 2024年第8期30卷 779-793页

作者： john K Triantafillidis Manousos M Konstadoulakis Apostolos e Papalois Inflammatory Bowel Disease Unit “Metropolitan General”HospitalHolargos 15562AtticaGreece.Hellenic Society for Gastrointestinal Oncology354 Iera OdosChaidari 12461AtticaGreece Second Department of Surgery University of Athens School of MedicineAretaieion HospitalAthens 11528AtticaGreece Unit of Surgical Research and Training Second Department of SurgeryUniversity of AthensSchool of MedicineAretaieion HospitalAthens 11528AtticaGreece

In this editorial,we comment on the article entitled“Advances and key focus areas in gastric cancer immunotherapy:A comprehensive scientometric and clinical trial review(1999-2023),”which was published in the recent issue of the World Journal of *** focused on the results of the authors’bibliometric analysis concerning gastric cancer immunotherapy,which they analyzed in depth by compiling the relevant publications of the last 20 *** that,we briefly describe the most recent data concerning the epidemiological parameters of gastric cancer(Gc)in different countries,attempting to give an interpretation based on the etiological factors involved in the etiopathogenesis of the *** then briefly discuss the conservative treatment(chemotherapy)of the various forms of this malignant *** describe the treatment of resectable tumors,locally advanced neoplasms,and unresectable(advanced)*** attention is given to modern therapeutic approaches with emphasis on immunotherapy,which seems to be the future of Gc treatment,especially in combination with *** is also a thorough analysis of the results of the study under review in terms of the number of scientific publications,the countries in which the studies were conducted,the authors,and the scientific centers of origin,as well as the clinical studies in ***,an attempt is made to draw some conclusions and to point out possible future directions.

关键词： Gastric cancer chemotherapy Immunotherapy Immune checkpoint inhibitors Bibliometrics Scientometrics