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Plant geranylgeranyl diphosphate synthases: every (gene) family has a story

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aBIOTECH 2021年第3期2卷 289-298页

作者： M.Victoria Barja manuel Rodriguez-Concepcion Centre for Research in Agricultural Genomics(CRAG)CSIC-IRTA-UAB-UB Campus UAB Bellaterra08193 Barce-lonaSpain Institute for Plant Molecular and Cell Biology(BMCP) CSIC-Universitat Politecnica de Valencia46022 ValenciaSpain

Plant isoprenoids(also known as terpenes or terpenoids)are a wide family of primary and secondary metabolites with multiple *** particular,most photosynthesis-related isoprenoids(including carotenoids and chlorophylls)as well as diterpenes and polyterpenes derive from geranylgeranyl diphosphate(GGPP)produced by GGPP synthase(GGPPS)enzymes in several cell *** genomes typically harbor multiple copies of differentially expressed genes encoding GGPPS-like *** sequence comparisons allow to identify potential GGPPS candidates,experimental evidence is required to ascertain their enzymatic activity and biologi cal ***,functional analyses of the full set of potential GGPPS paralogs are only available for a handful of plant *** we review our current knowledge on the GGPPS families of the model plant Arabidopsis thaliana and the crop species rice(0ryza sativa),pepper(Capsicum annuum)and tomato(Solanum lycopersicum).The results indicate that a major determinant of the biological role of particular GGPPS paralogs is the expression profile of the corresponding genes even though specific interactions with other proteins(including GGPP-consuming enzymes)might also contribute to *** some species,however,a single GGPPS isoforms appears to be responsible for the production of most if not all GGPP required for cell *** the mechanisms regulating GGPPS activity in particular cell compartments,tissues,organs and plant species will be very useful for future metabolic engineering approaches aimed to manipulate the accumulation of particular GGPP-derived products of interest without negatively impacting the levels of other isoprenoids required to sustain essential cell functions.

关键词： Geranylgeranyl diphosphate GGPP GGPP synthase Isoprenoid Isoprenyl transferase

Steatosis and insulin resistance in hepatitis C: A way out for the virus?

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world Journal of Gastroenterology 2009年第40期15卷 5014-5019页

作者： José A Del Campo manuel Romero-Gómez Unit for The Clinical Management of Digestive Diseases and CIBERehd Hospital Universitario de Valme

The hepatitis C virus (HCV) induces lipid accumulation in vitro and in vivo. The pathogenesis of steatosis is due to both viral and host factors. Viral steatosis is mostly reported in patients with genotype 3a, whereas meta-bolic steatosis is often associated with genotype 1 and metabolic syndrome. Several molecular mechanisms responsible for steatosis have been associated with the HCV core protein, which is able to induce gene expres-sion and activity of sterol regulatory element binding protein 1 (SREBP1) and peroxisome proliferator-activat-ed receptor γ (PPARγ), increasing the transcription of genes involved in hepatic fatty acid synthesis. Steatosis has been also implicated in viral replication. In infected cells, HCV core protein is targeted to lipid droplets which serve as intracellular storage organelles. These studies have shown that lipid droplets are essential for virus assembly. Thus, HCV promotes steatosis as an eff icient mechanism for stable viral replication. Chronic HCV in-fection can also induce insulin resistance. In patients with HCV, insulin resistance is more strongly associated with viral load than visceral obesity. HCV seems to lead to insulin resistance through interference of intracellular insulin signalling by HCV proteins, mainly, the serine phosphorylation of insulin receptor-1 (IRS-1) and im-pairment of the downstream Akt signalling pathway. The HCV core protein interferes with in vitro insulin signal-ling by genotype-specif ic mechanisms, where the role of suppressor of cytokine signal 7 (SOCS-7) in genotype 3aand mammalian target of rapamycin (mTOR) in geno-type 1 in IRS-1 downregulation play key roles. Steatosis and insulin resistance have been associated with f ibrosis progression and a reduced rate of sustained response to peginterferon plus ribavirin.

关键词： Steatosis Insulin resistance Hepatitis Cvirus

Normozoospermic versus teratozoospermic domestic cats： differential testicular volume, sperm morphometry, and subpopulation structure during epididymal maturation

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Asian Journal of Andrology 2016年第6期18卷 871-878页

作者： Miguel Angel Gutierrez-Reinoso manuel Garcia-Herreros National Secretariat of Higher Education Science Technology and Innovation (SENESCYT) Quito Ecuador

Teratozoospermia （〈40% morphologically normal spermatozoa/ejaculate） is a frequent phenomenon in feline species. This research was carried out to study the possible differences in testicular volume, differential sperm morphometric traits, and potential differences regarding the sperm subpopulational structure during epididymal sperm maturation in teratozoospermic feline donors. Epididymal sperm samples were collected from the caput （R1）, corpus （R2）, and cauda （R3） epididymidis in two donor groups （N： normozoospermic; T： teratozoospermic）. Aliquots were assessed for concentration, viability, motility, and acrosomal integrity. Sperm morphometric descriptors from CASA-Morph analysis were analyzed by the Principal Component Analysis （PCA） and clustering analyses. Irrespective of the group analyzed, PCA revealed two Principal Components （PCs） for each epididymal region explaining more than the 93% of the variance. Surprisingly, the number of subpopulations remained constant in regions R1-R2-R3 irrespective of the donor group analyzed. However, the distribution of these subpopulations was found to be structurally different and strongly influenced by the epididymal region and the donor group. In conclusion, testicular morphometry and the sperm subpopulation structure were different in N and T donors. The alterations in subpopulations during epididymal maturation could be used as a potential clinical indicator of teratozoospermic individuals since an important influence of teratozoospermia on sperm subpopulation structure has been demonstrated.

关键词： epididymis feline sperm morphometry sperm subpopulations teratozoospermia testicular volume

Catenoidal Layers for the Allen-Cahn Equation in Bounded Domains

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Chinese Annals of Mathematics,Series B 2017年第1期38卷 13-44页

作者： Oscar AGUDELO manuel DEL PINO Juncheng wEI Department of Mathematics Zapadocescka Univerzita v PlzniPlzenCzech Republic Departamento de Ingenieria Matematica and CMM Universidad de ChileCasilla 170 Correo 3SantiagoChile Department of Mathematics University of British ColumbiaVancouver BC V6T 1Z2Canada

This paper presents a new family of solutions to the singularly perturbed Allen-Cahn equation α~2Δu + u(1- u^2) = 0 in a smooth bounded domain Ω R^3, with Neumann boundary condition and α > 0 a small parameter. These solutions have the property that as α→ 0, their level sets collapse onto a bounded portion of a complete embedded minimal surface with finite total curvature intersecting ?Ω orthogonally and that is non-degenerate respect to ?Ω. The authors provide explicit examples of surfaces to which the result applies.

关键词： Allen-Cahn equation Critical minimal surfaces Critical catenoid Infinite dimensional gluing method Neumann boundary condition

Impact of anastomotic leakage on long-term prognosis after colorectal cancer surgery

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world Journal of Gastrointestinal Surgery 2023年第5期15卷 745-756页

作者： Valeria Tonini manuel Zanni Department of Medical and Surgical Sciences University of BolognaBologna 40138BolognaItaly

Colorectal cancer(CRC)is one of the most common malignancies in the *** significant improvements in surgical technique,postoperative complications still occur in a fair percentage of patients undergoing colorectal *** most feared complication is anastomotic *** negatively affects shortterm prognosis,with increased post-operative morbidity and mortality,higher hospitalization time and ***,it may require further surgery with the creation of a permanent or temporary *** there is no doubt about the negative impact of anastomotic dehiscence on the short-term prognosis of patients operated on for CRC,still under discussion is its impact on the long-term *** authors have described an association between leakage and reduced overall survival,disease-free survival,and increased recurrence,while other Authors have found no real impact of dehiscence on long term *** purpose of this paper is to review all the literature about the impact of anastomotic dehiscence on long-term prognosis after CRC *** main risk factors of leakage and early detection markers are also summarized.

关键词： Anastomotic leakage Colorectal surgery Colon cancer Rectal cancer Long term prognosis Long term survival

Effect of rhenium on the microstructure and mechanical behavior of Fe–2.25Cr–1.6w–0.25V-0.1C bainitic steels

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Journal of Materials Science & Technology 2017年第12期33卷 1487-1493页

作者： José Antonio Jiménez manuel Carsí Oscar Antonio Ruano Department of Physical Metallurgy Centro Nacional de lnvestigaciones MetalurgicasC.S.I.CAvda.Gregorio del Amo 828040 MadridSpain

A new ferritic creep resistant steel has been developed by eliminating Nb and adding 1.5 mass % Re to a ferritic steel grade T/P23 with the aim of enhancing its mechanical properties at high *** ingots of both steels, new grade and ASTM T/P 23, were hot rolled at 900℃ and then submitted to a thermal treatment consisting of solubilization at 1050℃ and tempering at 700℃. Tempered bainitic microstructures obtained contain second phases reinforcing carbide particles, mainly M_6C and M_（23）C_6 at the boundaries of both, prior austenite grains and bainitic ferrite laths, as well as MC within the grains. Mechanical properties at temperatures ranging from 540 to 600℃ were studied by strain-ratechange tests in compression at strain rates between 10^（-7） and 10^（-4）s^（-1）. These tests showed high stress exponents（n ≥ 20） and activation energies（Q ≈ 400 k J/mol） for both alloys, which were associated with a dislocation movement mechanism with a strong interaction between dislocations and precipitates. On the other hand, a creep exponent of 5 was derived for the stress dependence of minimum creep rate from conventional-type creep tests at 600℃. Although this stress exponent is usually related to a dislocation climb controlled creep mechanism, remarkable microstructural degradation observed with increasing creep time makes difficult to elucidate the true deformation mechanism controlling creep.

关键词： Creep resistant steel T/P23 Thermal treatment Tempered bainite High temperature mechanical properties Creep

Nonlinear optical properties in n-type quadrupleδ-doped GaAs quantum wells

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Chinese Physics B 2022年第4期31卷 348-351页

作者： Humberto Noverola-Gamas Luis manuel Gaggero-Sager Outmane Oubram Division Academica de Ingenierıa y Arquitectura Universidad Juarez Autonoma de TabascoCarretera Cunduacan-Jalpa de Mendez Km.1 Col.La EsmeraldaCunduacan8660Mexico Centro de Investigacion en Ingenierıa y Ciencias Aplicadas Universidad Autonoma del Estado de MorelosAv.Universidad 1001 Col.ChamilpaCuernavaca62209Mexico Facultad de Ciencias Quımicas e Ingenierıa Universidad Autonoma del Estado de MorelosAv.Universidad 1001 Col.ChamilpaCuernavaca62209Mexico

The effects of the interlayer distance on the nonlinear optical properties of n-type quadrupleδ-doped GaAs quantum well were theoretically ***,the absorption coefficient and the relative refraction index change were *** the effective mass approach and within the framework of the Thomas-Fermi theory,the Schrodinger equation was ***,the subband energy levels and their respective wave functions were *** variations in the nonlinear optical properties were determined by using the density matrix *** achieved results demonstrate that the interlayer distance causes optical red-shift on nonlinear optical ***,it can be deduced that the suitably chosen interlayer distance can be used to tune optical properties within the infrared spectrum region in optoelectronic devices such as far-infrared photo-detectors,high-speed electronic-optical modulators,and infrared lasers.

关键词： delta-doping n-type GaAs layers electronic structure non-linear optical properties

Beyond network centrality: individual-level behavioral traits for predicting information superspreaders in social media

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National Science Review 2024年第7期11卷 148-157页

作者： Fang Zhou Linyuan Lü Jianguo Liu manuel Sebastian Mariani Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of China Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of China School of Cyber Science and Technology University of Science and Technology of China Department of Digital Economics Shanghai University of Finance and Economics URPP Social Networks Universit?t Zürich

Understanding the heterogeneous role of individuals in large-scale information spreading is essential to manage online behavior as well as its potential offline consequences. To this end, most existing studies from diverse research domains focus on the disproportionate role played by highly connected ‘hub’ ***, we demonstrate here that information superspreaders in online social media are best understood and predicted by simultaneously considering two individual-level behavioral traits: influence and susceptibility. Specifically, we derive a nonlinear network-based algorithm to quantify individuals' influence and susceptibility from multiple spreading event data. By applying the algorithm to large-scale data from Twitter and weibo, we demonstrate that individuals' estimated influence and susceptibility scores enable predictions of future superspreaders above and beyond network centrality, and reveal new insights into the network positions of the superspreaders.

关键词： complex networks social networks social media information spreading superspreaders

Hepatitis C virus clearance and less liver damage in patients with high cholesterol, low-density lipoprotein cholesterol and APOE ε4 allele

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world Journal of Gastroenterology 2019年第38期25卷 5826-5837页

作者： Karina Gonzalez-Aldaco Sonia Roman Rafael Torres-Valadez Claudia ojeda-Granados Luis A Torres-Reyes Arturo Panduro Department of Molecular Biology in Medicine Civil Hospital of Guadalajara "Fray Antonio Alcalde" and Health Sciences Center University of Guadalajara

BACKGROUND Cholesterol is related to improvements in the rate of sustained virological response and a robust immune response against the hepatitis C virus(HCV).APOE gene polymorphisms regulate cholesterol levels modifying the course of the HCV *** relationship between cholesterol,APOE alleles,and the outcome of HCV infection has not been evaluated in the admixed population of *** To investigate the role of APOE-ε2,-ε3,and-ε4 alleles and the metabolic profile in the outcome of HCV *** A total of 299 treatment-na?ve HCV patients were included in this retrospective *** were stratified in chronic hepatitis C(CHC)(n=206)and spontaneous clearance(SC)(n=93).A clinical record was *** tests were assessed by dry chemistry *** genotypes were determined using a Real-Time polymerase chain reaction *** Total cholesterol,low-density lipoprotein cholesterol(LDL-c),triglycerides,and hypercholesterolemia were higher in SC than CHC patients as well as the frequency of the APOEε4 allele(12.4%vs 7.3%).SC patients were overweight(54.8%).Theε4 allele was associated with SC(OR=0.55,95%CI:0.31-0.98,P=0.042)and mild fibrosis(F1-F2)in CHC patients(OR 0.091,95%CI 0.01-0.75,P=0.020).LDL-c≥101.5 mg/dL(OR=0.20,95%CI:0.10-0.41,Pwere associated with SC status;while ALT≥50.5 IU/L was negatively associated(OR=5.67,95%CI:2.69-11.97,Pweight.

关键词： Liver damage Body mass index Spontaneous hepatitis C virus clearance Low-density lipoprotein Cholesterol