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Natural regeneration in logging gaps of different sizes in Subri River Forest Reserve(Ghana)

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Journal of Forestry Research 2022年第4期33卷 1157-1174页

作者： Maame esi Hammond Radek Pokorný Simon Abugre Augustine Gyedu Department of Silviculture Faculty of Forestry and Wood TechnologyMendel University in BrnoZemědělská361300 BrnoCzech Republic Department of Forest Science School of Natural ResourcesUniversity of Energy and Natural ResourcesP.O.Box 214SunyaniGhana Forest Services Division(FSD) P.M.BKumasiGhana

Subri River Forest Reserve(SR)is the most extensive forest area in Ghana with an accompanying rich floral *** the years,logging from both legally prescribed and illegal operations remain the predominant forest disturbance in *** creation following logging is crucial in determining tree species composition and ***,the study evaluated the composition and diversity of naturally regenerated tree species in logging gaps of different sizes and,again examined the roles of these tree species in fulfilling the economic and ecological agenda of sustainable forest management after logging in *** gaps were randomly selected:4 each were grouped into small size(≤200 m^(2)),medium size(201–300 m^(2)),and large size(≥300 m^(2)).Data were gathered from 1 m^(2) circular area at gap centres and repeatedly inside 1 m width strip along 20 m individual N-S-E-W *** diversity differed significantly between gap *** diversity indices were measured in large size *** sizes shared similar *** were significant differences among various height groupings of tree species across all three gap *** preferred medium to large size gaps,while shadetolerant tree species preferred small size gaps for their *** and Lower Risk Near Threatened tree species under Conservation Status and,Premium and Commercial tree species under Utilisation Status preferred small size gaps for their proliferation and ***,we recommend the single tree-based selective logging for ensuring creations of small to medium size(200–300 m^(2))gaps through adjustments to the logging permit process,revision of Allocation Quota Permit,strict adherence to the 40-year polycyclic selection system,along with more dedicated enforcement and *** along these protocols would tremendously facilitate natural regeneration of different suites of timber species resulting in the improvement of the overall biodiversity conservat

关键词： Conservation status Gap size Diversity Logging Natural regeneration Subri River Forest Reserve Tree species Utilisation status

Structure and functions of the translation initiation factor eIF4E and its role in cancer development and treatment

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Journal of Genetics and Genomics 2018年第1期45卷 13-24页

作者： Arianna Pisera Adele campo Salvatore campo Department of Biomedical and Dental Sciences and Morphofunctional Images Policlinico Universitario University of Messina Messina 98125 Italy

In eukaryotic cells, protein synthesis is a complex and multi-step process that has several mechanisms to start the translation including cap-dependent and cap-independent initiation. The translation control of eukaryotic gene expression occurs principally at the initiation step. In this context, it is critical that the eukaryotic translation initiation factor eIF4E bind to the 7-methylguanosine （m7G） cap present at the 5＇- UTRs of most eukaryotic mRNAs. Combined with other initiation factors, elF4E mediates the mRNA recruitment on ribosomes to start the translation. Moreover, the eIF4E nuclear bodies are involved in the export of specific mRNAs from the nucleus to the cytoplasm. In this review, we focus on the elF4E structure and its physiological functions, and describe the role of eIF4E in cancer development and progression and the current therapeutic strategies to target eIF4E.

关键词： elF4E factor Translation initiation mRNA exportCancer

SOME CLASSES OF DIFFERENCE SEQUENCES OF FUZZY NUMBERS DEFINED BY A SEQUENCE OF MODULI

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Acta Mathematica Scientia 2011年第1期31卷 229-236页

作者： Ayhan esi Mehmet Aikgz Department of Mathematics Science and Art Faculty Adiyaman University Department of Mathematics Faculty of Science and Literature University of Gaziantep

In this article, we introduce and examine some properties of new difference sequence spaces of fuzzy numbers defined using a sequence of modulus functions.

关键词： Fuzzy numbers paranorm difference sequences modulus function

The composition and diversity of natural regeneration of tree species in gaps under different intensities of forest disturbance

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Journal of Forestry Research 2021年第5期32卷 1843-1853页

作者： Maame esi Hammond Radek Pokorný Daniel Okae-Anti Augustine Gyedu Irene Otwuwa Obeng Department of Silviculture Faculty of Forestry and Wood TechnologyMendel University in BrnoZemedelska 361300 BrnoCzech Republic Department of Soil Science School of AgricultureUniversity of Cape CoastP.M.BCape CoastGhana Forestry Services Division(FSD) P.M.BKumasiGhana 4 Madina-AccraGhana

The positive ecological interaction between gap formation and natural regeneration has been examined but little research has been carried out on the effects of gaps on natural regeneration in forests under different intensities of *** study evaluates the composition,diversity,regeneration density and abundance of natural regeneration of tree species in gaps in undisturbed,intermittently disturbed,and disturbed forest *** Tano Forest Reserve in Ghana was the study area and three gaps each were selected in the three forest site *** circular subsampling areas of 1 m2 were delineated at 2 m spacing along north,south,east,and west transects within individual *** on natural regeneration<350 cm height were *** results show that the intensity of disturbance was disproportional to gap *** diversity differed significantly between undisturbed and disturbed sites and,also between intermittently disturbed and disturbed sites for Simpson’s(1-D),Equitability(J),and Berger-Parker(B-P)***,there was no significant difference among forest sites for Shannon diversity(H)and Margalef richness(MI)*** species composition on the sites *** density on the disturbed site was significantly higher than on the two other *** abundance and density of shade-dependent species on all sites identified them as opportunistic replacements of gap-dependent *** species giving way to shade tolerant species is a natural process,thus make them worst variant in gap regeneration.

关键词： Disturbed Intermittently disturbed Undisturbed Forest sites Gap regeneration

Comparative analysis of thinning techniques in pine forests

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Journal of Forestry Research 2022年第4期33卷 1145-1156页

Thinning is a necessary and complex forestry *** complexity increases due to theoretical disagreements,contradictory recommendations,and errors of modern practice,which require confirmation through longtime *** article presents a summary of experimental results from plantations established 20–30 years ago and explains concepts of the theory,methods,and regime of thinning in permanent sample plots of pine stands in Gatchinsky forest of the Leningrad *** research results allow for the clarification of growth patterns and age dynamics of pine stands subject to heavy,low thinning,as well as the results of applying the crown(high)thinning technique and a mixed treatment.A combined thinning and fertilization could improve wood quality and yield compared to conventional *** particular scientific importance is the analysis of change in tree diameter classes during growth and after *** research results allow for optimizing the treatment regime in pine plantations and reducing labor intensity by increasing the intensity of thinning and reducing the number of techniques.

关键词： Forest management practices Forest stand Selective thinning Silviculture

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

Frailty in patients admitted to hospital for acute coronary syndrome: when, how and why?

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Journal of Geriatric Cardiology 2019年第2期16卷 129-137页

作者： Elisabetta Tonet Rita Pavasini Simone Biscaglia Gianluca campo Cardiovascular Institute Azienda Ospedaliero-Universitaria di FerraraConaItaly Maria Cecilia Hospital GVM Care&ResearchCotignolaItaly

Frailty is an issue of paramount importance for cardiologists,because of the aging of patients admitted to hospital for acute coronary syndrome(ACS)and the straight relationship between aging and *** tools have been provided in this setting,in order to objectively assess frailty status,but important questions are still *** are conflicting data about a unique definition of frailty in subjects with cardiovascular diseases,the timing to perform a frailty evaluation in the context of an acute myocardial infarction,the mean to assess frailty in these patients and the usefulness of the information derived from the frailty *** results from the analysis of several items and a multidomain evaluation including laboratory values,clinical data and physical performance assessment is required for a comprehensive frailty ***,regardless of the frailty tool,the prevalence of frailty in older ACS patients is high and it could add important information to the decision-making process about invasive strategy,the multivessel disease management,dual antiplatelet therapy and secondary prevention *** present overview tries to summarize the current knowledge about the definition and prevalence of frailty in older adults admitted to hospital for ACS,suggesting how frailty assessment may improve the management of older ACS patients.

关键词： Acute coronary syndrome Frailty The elderly

Melting behavior and globular microstructure formation in semi-solid CoCrCuxFeNi high-entropy alloys

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Journal of Materials Science & Technology 2020年第17期52卷 207-217页

作者： Kaio Niitsu campo Caio Chaussêde Freitas Leonardo Fanton Rubens Caram University of Campinas School of Mechanical EngineeringSPBrazil

High-entropy alloys can be compelling raw materials for semi-solid *** the present study,the influence of the Cu content on the melting behavior and semi-solid microstructure of CoCrCuxFeNi(x=0,1,2,3)alloys was ***-melted samples were cross-rolled at room temperature and then isothermally treated at 1175℃in the semi-solid state for 300 *** characterization showed that the alloys containing Cu were formed by two fcc ***,the increase in Cu content also led to an increase in the volumetric fraction of the Cu-rich *** solidification,this phase,which is the last to form,nucleates and epitaxially grows on the Cu-lean *** the studied CoCrCuFeNi alloys exhibited the same melting *** Cu-rich phase melts at approximately 1120℃,whereas the Culean phase melts at approximately 1350℃,providing a suitable processing temperature range of more than 200℃.The semi-solid microstructures were considerably refined and globular regardless of the alloy composition,being suitable for semi-solid ***,each fcc phase exhibited roughly the same composition under the different processing *** Cu content in the Cu-lean phase was approximately 10 at.%,while Co,Cr,Fe,and Ni were in an approximately equiatomic ***,the Cu content was between 80 at.%and 86 at.%in the Cu-rich *** isothermal treatment of the CoCrCu3FeNi alloy at a higher temperature(1300℃)only caused the globules to *** conclusion,this work showed that these alloys can be potential candidates for semi-solid processing.

关键词： Semi-solid processing Thixoforming High-entropy alloys Microstructure

Key Factors Involved in Lamb Quality from Farm to Fork in Europe

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Journal of Integrative Agriculture 2013年第11期12卷 1919-1930页

作者： Carlos Saudo Erica Muela María del Mar campo Department of Animal Production and Food Science University of Zaragoza

World lamb consumption is approximately 2 kg per capita with large variations between continents, e.g., 17 kg in Oceania vs. 0.7 kg in North America. With less than one million tonnes, the international trade of sheep meat contributes to a small percentage of the total meat exchanged between countries. On the other hand, lamb represents the highest rate of species trading in relation to the total sheep meat produced. It is therefore likely to ifnd a wide variability of different lamb products in the same market, and that the conservation procedures （such as refrigeration, packaging or freezing）, chemical composition, especially the fat due to its implication in human health, lfavour development and juiciness perception （affected, i.e., by the feeding or the age or slaughter weight of the animal） and acceptability （based on culinary background） could be considered important indicators of this advantageous situation. In this paper some studies related to the aforementioned indicators are discussed.

关键词： technology chemical composition consumer preferences