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(4 + 4)-Dimensional Space-Time as a Dual Scenario for Quantum Gravity and Dark Matter

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Journal of Applied Mathematics and Physics 2022年第3期10卷 688-702页

作者： Brandon mariano martínez-Olivas Juan Antonio nieto Andrés Sandoval-Rodríguez Facultad de Ciencias Fsico-Matemáticas de la Universidad Autónoma Culiacán Sinaloa México

In this work, we make a number of proposals to explain how a world of (4 + 4)-dimensions can be useful for a better understanding of both dark matter and quantum gravity. The key idea is to look for some advantage of considering self-dual invariants in (4 + 4)-dimensions rather than in a separate context of (1 + 3)-dimensions or (3 + 1)-dimensions. In fact, we show that by considering the duality concept in (4 + 4)-dimensions we may provide an alternative meaning of a framework for loop quantum gravity. Moreover, considering the Dirac equation in (4 + 4)-dimensions for a particle without electric charge and mass, we show that when it is projected into the (1 + 3) and (3 + 1)-worlds may describe a system with electric charge and mass. We also discuss the relation between the three physical scenarios;(4 + 4)-world, black-holes and dark matter.

关键词： (4 + 4)-Dimensions Dark Matter Quantum Gravity

New real-time-PCR method to identify single point mutations in hepatitis C virus

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World Journal of Gastroenterology 2016年第43期22卷 9604-9612页

作者： Qian Chen Irene Belmonte maria Buti Leonardo nieto Damir Garcia-Cehic Josep Gregori Celia Perales Laura Ordeig Meritxell Llorens maria Eugenia Soria Rafael Esteban Juan Ignacio Esteban Francisco Rodriguez-Frias Josep Quer Liver Unit Internal Medicine Lab. Malalties Hepàtiques Vall d’Hebron Institut Recerca-Hospital Universitari Vall d’ Hebron08035 Barcelona Spain Centro de Investigación Biomédica en Red Enfermedades Hepáticas y Digestivas Instituto de Salud Carlos Ⅲ28029 madrid Spain Liver Pathology Unit Departments of Biochemistry and Microbiology Hospital Universitari Vall d’Hebron Autonomous University of Barcelona 08035 Bareelona Spain Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas del Instituto de Salud Carlos Ⅲ 28029 Madrid Spain Universitat Autònoma de Barcelona 08193 Bareelona Spain

AIM To develop a fast, low-cost diagnostic strategy to identify single point mutations in highly variable genomes such as hepatitis C virus(HCV).METHODS In patients with HCV infection, resistance-associated amino acid substitutions within the viral quasispecies prior to therapy can confer decreased susceptibility to direct-acting antiviral agents and lead to treatment failure and virological relapse. One such naturally occurring mutation is the Q80 K substitution in the HCV-NS3 protease gene, which confers resistance to PI inhibitors, particularly simeprevir. Low-cost, highly sensitive techniques enabling routine detection of these single point mutations would be useful to identify patients at a risk of treatment failure. Light Cycler methods, based on real-time PCR with sequencespecific probe hybridization, have been implemented in most diagnostic laboratories. However, this technique cannot identify single point mutations in highly variable genetic environments, such as the HCV genome. To circumvent this problem, we developed a new method to homogenize all nucleotides present in a region except the point mutation of interest. RESULTS Using nucleotide-specific probes Q, K, and R substitutions at position 80 were clearly identified at a sensitivity of 10%(mutations present at a frequency of at least 10% were detected). The technique was successfully applied to identify the Q80 K substitution in 240 HCV G1 serum samples, with performance comparable to that of direct Sanger sequencing, the current standard procedure for this purpose. The new method was then validated in a Catalonian population of 202 HCV G1-infected individuals. Q80 K was detected in 14.6% of G1 a patients and 0% of G1 b in our setting. CONCLUSION A fast, low-cost diagnostic strategy based on real-time PCR and fluorescence resonance energy transfer probe melting curve analysis has been successfully developed to identify single point mutations in highly variable genomes such as hepatitis C virus. This

关键词： Hepatitis C virus Resistance-associated amino acid substitutions Low-cost test Single-point mutations Q80K

Immune Reactive Ezrin Surface Area Increases in Glomerular Podocytes of STZ Diabetic Rats Precede Their Detachment, Is Prevented by Phlorizin But Not by Insulin

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Journal of Diabetes Mellitus 2020年第2期10卷 27-40页

作者： Slava Malatiali Issam Francis Musleeha Chesor Gavin Welsh Moin Saleem mario Barac-nieto Departments of Physiology Faculty of Medicine Kuwait University Safat Kuwait Pathology Faculty of Medicine Kuwait University Safat Kuwait University of Bristol Pediatric Nephrology Bristol UK Retired 9443 Hickory Limb Colusmbia MD USA

Glomerular tuft immune reactive Ezrin surface area (EzA) and fraction of EzA to total glomerular tuft area significantly increased, indicating podocyte growth, rounding and altered cytoskeletal interactions at 1 week of STZ diabetes. Podocyte number per glomerulus (WT1+ nuclei) did not change indicating no detachment, but density decreased due to tuft hypertrophy. Treatment with PLZ or Insulin for one week, prevented increase in proteinuria and hyperglycemia but not the decrease in podocyte density. PLZ but not Insulin prevented increase in ezrin positive area in glomeruli and per podocyte. In podocytes in culture neither 25 mM glucose with or without PLZ (2.5 or 25 uM) altered Ezrin expression measured in western blots. In summary, the Ezrin positive glomerular surface area increase seen after 1 week of STZ diabetes, reflects altered podocyte morphology and cytoskeletal interactions, prevented by PLZ but not by insulin. Ezrin area increase preceded podocyte detachment and in podocytes in culture is not associated with increases in podocyte Ezrin protein expression. It is a likely precursor of shape changes in podocytes and of alterd interactions with basement membrane that contribute to detachment and thickening. Glomerular capillary tuft hypertrophy and reduced podocyte density persisted despite PLZ or insulin treatments, independently of levels of glycemia and of proteinuria.

关键词： Diabetes. Hyperglycemia Glomerular Hypertrophy Phlorizin Podocyte Density Ezrin

Conceptions in Teaching and Didactic Activities and Assessment of University Teachers

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Psychology Research 2014年第11期4卷 876-884页

作者： Jose Armando Pena Morenc Ma. Concepcion Rodriguez nieto Victor Manuel Padilla Montemayor Universidad Autonoma de Nuevo Leon Nuevo Leon Mexico

The aim of this study was to detect and analyze the conceptions of teaching, learning activities and assessment of learning in classroom, and blended courses for university professor＇s face-to-face courses. The study design was non-experimental, descriptive, and mixed cut. The sample was not random with participation of 129 university professors＇ face-to-face courses. As was applied, the open questions questionnaire on teaching and learning conceptions of teachers and data reported six questions related to the conception of teaching, didactic activities and assessment of learning of courses in classroom and blended courses. The data were worked through content analysis and percentages. The findings showed a conception of classroom teaching with a focus on learning and a conception blended teaching with a strong focus on teaching. The most reported didactic activities in classroom courses at a decreasing hierarchy were： exposition and presentation, se, discussion forums, chat and Wikis. In classroom assessment participation, and research and blended courses the research, Wikis, teachers did not specify evaluation resources case study and mixed courses, technology per courses predominated, in the abstract tests, forums and blog,

关键词： conceptions of teaching, conceptions of blended teaching, higher education

里德尔剪切的组合型式与走滑盆地组合型式的相似性

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地质论评 2017年第2期63卷 287-301页

作者：许顺山彭华 Angel F.nieto-SAMANIEGO 陈书平吴习东墨西哥国立自治大学地球科学中心墨西哥76001 中国地质科学院地质力学研究所北京100037 中国石油大学(北京)地球科学学院北京102249

走滑断裂体系中经常发育里德尔剪切的断裂组合,世界上不同构造背景下与走滑断裂相关的盆地(走滑盆地)也很多见。因此里德尔剪切是地质构造研究中的重要方面。我们从三个方面对里德尔剪切的节理构造组合及盆地组合进行了对比:(1)里德尔... 详细信息

走滑断裂体系中经常发育里德尔剪切的断裂组合,世界上不同构造背景下与走滑断裂相关的盆地(走滑盆地)也很多见。因此里德尔剪切是地质构造研究中的重要方面。我们从三个方面对里德尔剪切的节理构造组合及盆地组合进行了对比:(1)里德尔剪切构造组合与比例尺无关。里德尔剪切带的(转换)拉张区与沉积盆地的分布区是相似的;(2)断裂的最大位移区与断陷盆地的沉积中心是一致的,断陷盆地长轴平行于断裂走向;(3)物理模拟试验及数学模拟试验都证实了走滑盆地的演化。基于上述认识,我们通过厘米级岩芯标本的观察,结合已发表的盆地资料,提出了6类与里德尔剪切有关的构造组合及断陷盆地组合。(1)雁列状构造及盆地组合:许多盆地发育雁列状构造。同时,与里德尔剪切相关的雁列状盆地的宽度与主剪切断裂的剪切位移呈正相关。(2)帚状或马尾状构造及盆地组合:二者在形态上相似,所以归为一类。成因上,马尾状构造及盆地主要发育在走滑断裂的拉张端部,而帚状构造或盆地反映走滑断裂的旋扭作用,可以在走滑断裂影响区域的任何部位。(3)串珠状构造及盆地组合:该类型的盆地主要是指释压盆地的组合,拉分盆地也可以形成串珠状盆地。(4)S状或Z状构造或盆地组合:左行走滑形成Z状构造或盆地,而右行走划形成S状构造或盆地。(5)多字型构造及盆地组合:是拉分盆地的典型组合,可以过渡到串珠状盆地。(6)复杂的网状构造及盆地组合:通常是由于分布型简单剪切的作用结果。以上盆地组合类型包括大型盆地内次级单元(次级盆地或更次级盆地)的组合,但不包括多成因、多期活动的构造及盆地。

关键词：里德尔剪切走滑盆地拉分盆地构造组合盆地组合类型

Mixing Efficiency across Rayleigh-Taylor and Richtmeyer-Meshkov Fronts

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Open Journal of Fluid Dynamics 2015年第2期5卷 145-150页

作者： Jose Manuel Redondo Pilar Lopez Gonzalez-nieto Jose Leandro Cano German Andres Garzon Applied Physics Department Politecnica University of Catalu&#241 a (UPC) Barcelona Spain Applied Mathematics Department Complutense University of Madrid (UCM) Madrid Spain Earth Physics Astronomy and Astrophsics II Department Complutense University of Madrid (UCM) Madrid Spain

Mixing generated by gravitational acceleration and the role of local turbulence measured through multifractal methods is examined in numerical experiments of Rayleigh-Taylor and Richtmyer-Meshkov driven front occurring at density interfaces. The global advance of the fronts is compared with laboratory experiments and Nusselt and Sherwood numbers are calculated in both large eddy simulation (LES) and kinematic simulation KS models. In this experimental method, the mixing processes are generated by the evolution of a discrete set of forced turbulent plumes. We describe the corresponding qualitative results and the quantitative conclusions based on measures of the density field and of the height of the fluid layers. We present an experimental analysis to characterize the partial mixing process. The conclusions of this analysis are related to the mixing efficiency and the height of the final mixed layer as functions of the Atwood number, which ranges from 9.8 × 10−3 to 1.34 × 10−1.

关键词： Rayleigh-Taylor Instability Richtmyer-Meshkov Instability Mixing Efficiency Front Evolution Fractal Dimension

Practical Use of Stairs to Assess Fitness, Prescribe and Perform Physical Activity Training

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Health 2016年第13期8卷 1402-1410页

作者： Jasem Ramadan Al Kandari Salman Mohammad Ruqayyah Al-Hashem Girma Telahoun mario Barac-nieto Department of Physiology Faculty of Medicine Kuwait University Al-Khaldiya Kuwait Department of Physical Education College of Basic Education The Public Authority of Applied Education and Training Adailiyah Kuwait

Aim: Evaluating climbing stairs for prescription and implementation of physical activity regimes. Methods: Healthy females (F, n = 14), and males (M, n = 15) participated. By climbing 100 steps of stairs with 0.173 m height, Heart rate (HR) and oxygen uptake were measured throughout the floors;Blood pressure (BP) was measured at ground and the 5th floors only. Results: Energy increased from 2 to 7.6 was metabolic equivalents (METs = 3.5 ml O2/***) at 17.3 m elevation in 2 min. at the 5th floor, and percent Heart Rate Reserve (%HRR) was 66.17% in F and 48.7% in M, proportional to their aerobic efforts. Average climbing efficiency was 15.8 ± 2.3% (n = 29). Aerobic capacity estimated dividing the highest work rate (17.3 Kg.m/*** × 0.00239 = 0.0207 Kcal/***), by fractional effort (F = 0.6617, M = 0.487) and fractional efficiency (0.158), at 5 Kcal/L O2 was 0.040 in F and 0.054 L O2/*** in M. Minimum training intensity reached at the 3rd floor by F. In M the highest %HRR reached was 48.7% at the 5th floor, insufficient for training. Conclusions: Stairs used for submaximal evaluation of aerobic capacity and for target intensity prescription. Training, levels climbed, repetitions per day (if 5, 100 Kcal per day, ascending) and number of days/week are adjusted. Full regime requires up to 7.6 METs, a total of 532 and 140 ***/week ascending and descending, respectively. Intensities >7.6 MET, climbing rate should be >8.65 m/min. Limiting ascent to 1 (3.5 METs) or 2 (5.5 METs) floors or only descents (2 - 3 METs) may be used for unfit subjects. This method is useful for those with no access to sophisticated facilities.

关键词： Stair Climbing Descent Heart Rate Reserve Aerobic Effort Oxygen Cost Work Output Efficiency Aerobic Capacity Exercise Prescription Training

Kinetics of the H＋-ATPase from Dry and 5-Hours- Imbibed Maize Embryos in Its Native, Solubilized, and Reconstituted Forms

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Molecular Plant 2011年第3期4卷 505-515页

作者： Sobeida Sanchez-nieto Consuelo Enriquez-Arredondo Fernando Guzmbn-Chavez Rolando Hern&ndez-Munoz Jorge Ramirez marina Gavilanes-Ruiz Departamento de Bioquimica Facultad de Quimica Conjunto E. Universidad Nacional Autonoma de Mexico Cd Universitaria 04360 Mexico DF Mexico Instituto de Fisiologfa Celular Universidad Nacional Autonoma de Mexico Cd Universitaria 04360 Mexico DF Mexico

Membranes undergo recovery upon rehydration in seed germination. Previous work has described that the plasma membrane H＋-ATPase from maize embryos adopts two different forms at 0 and 5 h of imbibition. We investigated how the kinetics of these two forms could be affected by alterations in the plasma membrane （PM）. In comparison to the O-h, PMs from the 5-h imbibed embryos showed changes in glycerophospholipid composition, decrease in leakage, and increase in fluidity. Kinetics of the PM H^-ATPase from 0 and 5-h imbibed embryos showed negative cooperativity, With the removal of the membrane environment, the activity of the enzymes shifted to a more complex kinetics, displaying two enzyme components. Lipid reconstitution produced one component with positive cooperativity. In all cases, enzymes from 0 and 5-h imbibed embryos presented similar kinetics with some quantitative differences. These results indicate that the two enzyme forms have the potential ability to respond to changes in the membrane enyiror^rpent, but the fact that they do not show differences in the native membranes at 0 or 5 h implies that modifications in the membrane are not drastic enough to alter their kinetics, or that they are able to preserve their boundary lipids or associated proteins and thus retain the same kinetic behavior.

关键词： ATPase activity H^-ATPase maize germination plasma membrane H+-ATPase plasma membrane Zea mays.

Clinicopathological differences,risk factors and prognostic scores for western patients with intestinal and diffuse-type gastric cancer

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World Journal of Gastrointestinal Oncology 2022年第6期14卷 1162-1174页

作者： Cristina Díaz del Arco Lourdes Estrada Muñoz Luis Ortega Medina Elena Molina Roldán MÁngeles Cerón nieto Soledad García Gómez de las Heras M Jesús Fernández Aceñero Department of Surgical Pathology Hospital Clínico San CarlosMadrid 28040Spain Department of Legal Medicine Psychiatry and PathologyComplutense University of MadridMadrid 28040Spain Department of Surgical Pathology Hospital Rey Juan CarlosMadrid 28933Spain Department of Basic Medical Sciences Rey Juan Carlos UniversityMadrid 28933Spain

BACKGROUND In the molecular era,the Laurén system is still a cost-effective and widely implemented classification for gastric cancer(GC)and it has been recently associated with clinical,histological and molecular features of these *** recent advances in the understanding of the molecular biology of GC,there is a need to develop new prognostic tools for patient stratification in clinical ***,the identification of easily available prognostic factors in patients with intestinal and diffuse-type tumors can significantly improve risk assessment and patient stratification in *** To identify clinicopathological differences,risk factors,and to develop costeffective prognostic scores for patients with intestinal and diffuse-type *** Retrospective study of all patients undergoing surgery for GC at a tertiary referral center from 2001 to 2019.286 cases met inclusion criteria(intestinal:190,diffuse:96).Clinical data and gross findings were *** specimens were reviewed by two independent pathologists and a detailed protocol for histologic evaluation was *** tissue microarrays(TMAs)were constructed and sections of the TMA block were immunostained for HERCEPTEST,MSH2,MSH6,MLH1 and *** analyses were performed and prognostic scores were developed based on hazard *** Intestinal and diffuse-type GC showed different epidemiological,clinicopathological and prognostic *** tumors were significantly associated with younger age,less symptomatology,flat morphology,deeper invasion,perineural infiltration,advanced stage at diagnosis,administration of adjuvant therapy and poorer *** lesions were fungoid or polypoid,showed necrosis,desmoplasia,microsatellite instability and HERCEPTEST positivity and were diagnosed at earlier *** depth,desmoplasia,macroscopic type and lymph node involvement were independently related to the Laurén ***,intestinal and diffuse GC were asso

关键词： Gastric cancer Clinicopathological Score Prognosis Laurén Molecular