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Domestication-related changes in seed dispersal and pigmentation:Visual selection and functional trait?

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Molecular Plant 2023年第8期16卷 1240-1242页

作者： petr Smykal Travis Parker Department of Botany Palacky University in Olomouc77900 OlomoucCzech Republic Department of Plant Sciences University of CaliforniaDavisDavisCA 95616USA

The development of agriculture is one of the most transformative changes in the history of humankind.Among the most common changes occurring during plant domestication are reductions in seed dispersal and changes in pigmentation.Although there are archaeological records of these processes,the advancement of genomics offers a tool to achieve greater insight into the process of converting wild plants into crops(Smýkal et al.,2018).This involved and resulted in a set of specific phenotypic changes referred to collectively as the domestication syndrome.Recently,less obvious domestication-related modifications have also been identified,including changes in plant biochemistry.These processes are often intertwined.For example,among visible changes,selection for visual appearance such as pigmentation is governed by modulation of specific metabolic pathways.Like genomic tools,the improvement of analytical methods provides the opportunity to reveal metabolomic changes involved in plant domestication.

关键词： Visual collective crops

High‑throughput sequencing view on the magnitude of global fungal diversity

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Fungal Diversity 2022年第3期114卷 539-547页

作者： petr Baldrian TomášVětrovský Clémentine Lepinay petr Kohout Laboratory of Environmental Microbiology Institute of Microbiology of the Czech Academy of SciencesVídeňská108314220 Prague 4Czech Republic

High-throughput DNA sequencing has dramatically transformed several areas of biodiversity research including mycol-ogy.Despite limitations,high-throughput sequencing is nowadays a predominant method to characterize the alpha and beta diversity of fungal communities.Across the papers utilizing high-throughput sequencing approaches to study natural habitats in terrestrial ecosystems worldwide,>200 studies published until 2019 have generated over 250 million sequences of the primary mycological metabarcoding marker,the nuclear ribosomal internal transcribed spacer 2(ITS2).Here we show that at a 97%sequence similarity threshold,the total richness of non-singleton fungal taxa across the studies published so far is 1.08 million,mostly Ascomycota(56.8%of the taxa)and Basidiomycota(36.7%of the taxa).The Chao-1 estimate of the total extant fungal diversity based on this dataset is 6.28 million taxa,representing a conservative estimate of global fungal species richness.Soil and litter represent the habitats with the highest alpha diversity of fungi followed by air,plant shoots,plant roots and deadwood with Chao-1 predictions,for samples containing 5000 sequences,of 1219,569,392,228,215 and 140 molecular species,respectively.Based on the high-throughput sequencing data,the highest proportion of unknown fungal species is associated with samples of lichen and plant tissues.When considering the use of high-throughput sequenc-ing for the estimation of global fungal diversity,the limitations of the method have to be taken into account,some of which are sequencing platform-specific while others are inherent to the metabarcoding approaches of species representation.In this respect,high-throughput sequencing data can complement fungal diversity predictions based on methods of traditional mycology and increase our understanding of fungal biodiversity.

关键词： High-throughput sequencing Metabarcoding Internal transcribed spacer Alpha diversity Meta-analysis

Liquid superlubricity of lubricants containing hydroxyl groups and their aqueous solution under rolling/sliding conditions

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Friction 2024年第1期12卷 164-173页

作者： Tomáš POLÁČEK petr ŠPERKA Ivan KŘUPKA Faculty of Mechanical Engineering Brno University of TechnologyBrno 61669Czech Republic

Macroscale rolling/sliding conditions are in the superlubricity,a little-studied topic so far.The purpose of this paper is to examine the formation of elastohydrodynamic lubrication(EHL)films by water-based lubricants(glycerol and polyethylene glycol(PEG)),providing superlubricous friction.Experiments were carried out on an optical ball-on-disc tribometer under rolling/sliding conditions.The film thickness was measured by the thin film colorimetric interferometry,and the viscosity of liquids was measured by rotational and high-pressure falling body viscometers.The results show that tribochemical reactions are not the mandatory reason for friction to reach the superlubricity level when using the water-based lubricants.The studied liquids themselves are almost Newtonian.With the addition of water,the signs of shear thinning behavior disappear even more.Suitable conditions for this type of lubricant can be predicted using the known Hamrock–Dowson equations.An anomaly in the thickness of the lubricants was observed as an abrupt change at certain conditions.The more PEG there is in the lubricant,the higher the thickness at the beginning of the jump.

关键词： macroscale superlubricity super low traction water-based lubricants elastohydrodynamic lubrication(EHL) film thickness

Heavy rockbursts due to longwall mining near protective pillars:A case study

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International Journal of Mining Science and Technology 2018年第5期28卷 799-805页

作者： petr Konicek Jan Schreiber Department of Geomechanics and Mining Research Institute of Geonics Czech Academy of Science

Rockburst represents a very dangerous phenomenon in deep underground mining in unfavourable conditions such as great depth, high horizontal stress, proximity of important tectonic structures, and unmined pillars. The case study describes a recorded heavy rockburst in the Czech part of the Upper Silesian Coal Basin, which occurred during longwall mining near the protective pillar. The artificial dividing of geological blocks and creation of mining protective pillars(shaft pillars, crosscut pillars etc.) is a dangerous task in light of rockbursts occurring mainly due to overstressing of remaining pillars. A simple model of this situation is presented. Natural and mining conditions are analysed and presented in detail as well as registered seismicity during longwall mining in the area. Recorded rockbursts in the area of interest are described and their causes discussed. Many rockbursts near protective pillars were recorded in this mining region. Methodical instructions for rockburst prevention in proximity of protective pillars as well as for gates driving were devised based on the evaluation of rockburst causes. The paper presents these principles for prevention.

关键词： Rockburst Rockburst prevention Hardcoal longwall mining Induced seismicity Protective pillar

Study on the Numerical Model of Transonic Wind Tunnel Test Section

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Journal of Thermal Science 2021年第1期30卷 231-241页

作者： LOUDA petr PŘÍHODA Jaromír Institute of Thermomechanics of the Czech Academy of Sciences Prague 818200Czech Republic Faculty of Mechanical Engineering Czech Technical UniversityPrague 212135Czech Republic

The authors consider numerical simulations of transonic flows through various turbine cascades in a confined channel which approximates boundaries of real wind tunnel.The boundaries of the wind tunnel are impermeable or there can be permeable tailboards to diminish shock wave reflections.The mathematical model is based on Favre-averaged Navier-Stokes equations closed by a turbulence model and model of transition to turbulence.The mathematical model is solved by an implicit finite volume method with multi-block grids.Several types of turbine blade cascades with subsonic or supersonic inlet are presented.The results are compared with optical measurements and simulations of periodic cascades.The validity of experimental reference flow parameters in relation to computed flow patterns is discussed.

关键词： perforated wall model transonic wind tunnel turbine blade cascade

Clinical and socioeconomic determinants of survival in biliary tract adenocarcinomas

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1374-1383页

作者： Laura Sahyoun Kay Chen Cynthia Tsay George Chen petr Protiva Department of Gastroenterology and Hepatology Weill Cornell MedicineNew YorkNY 10065United States Gastroenterology Section Jennifer Moreno VA San Diego Healthcare SystemSan DiegoCA 92161United States Division of Gastroenterology Department of MedicineUniversity of California San DiegoLa JollaCA 92093United States Department of Gastroenterology and Hepatology John Hopkins HospitalBaltimoreMD 21287United States Department of Digestive Diseases Yale New Haven HospitalNew HavenCT 06520United States Department of Gastroenterology VA Connecticut Health Care SystemWest HavenCT 06516United States

BACKGROUND Despite advances in detection and treatments,biliary tract cancers continue to have poor survival outcomes.Currently,there is limited data investigating the significance of socioeconomic status,race/ethnicity,and environmental factors in biliary tract cancer survival.Data from the Surveillance,Epidemiology,and End Results database for biliary and gallbladder adenocarcinomas were extracted from 1975 to 2016.Socioe-conomic data included smoking,poverty level,education,adjusted household income,and percentage of foreign-born persons and urban population.Survival was calculated with Cox proportional hazards models for death in the 5-year period following diagnosis.RESULTS Our study included 15883 gallbladder,11466 intrahepatic biliary,12869 extrahepatic biliary and 7268 ampulla of Vater adenocarcinoma cases.When analyzing county-specific demographics,patients from counties with higher incomes were associated with higher survival rates[hazard ratio(HR)=0.97,P<0.05].Similarly,counties with a higher percentage of patients with a college level education and counties with a higher urban population had higher 5-year survival rates(HR=0.96,P=0.002 and HR=0.97,P=0.004,respectively).CONCLUSION Worse survival outcomes were observed in lower income counties while higher income and education level were associated with higher 5-year overall survival among gallbladder and biliary malignancies.

关键词： Biliary tract cancers Survival Outcomes research Socioeconomic factors Healthcare disparities

Nano storage-boxes constructed by the vertical growth of MoS_(2 )on graphene for high-performance Li-S batteries

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Journal of Energy Chemistry 2022年第3期31卷 91-99,I0004页

作者： Bowen Cui Xiaomin Cai Wenqiang Wang petr Saha Gengchao Wang Shanghai Key Laboratory of Advanced Polymeric Materials Shanghai Engineering Research Center of Hierarchical NanomaterialsSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China Centre of Polymer Systems University InstituteTomas Bata UniversityTř.T.Bati 5678Zlin 76001ZlínCzech Republic

In order to accelerate the reaction kinetics of lithium-sulfur batteries, the introduction of electro catalysis and proper structural control of the sulfur cathode is urgently needed. MoS_(2) nano sheets was selectively grown vertically (V-MoS_(2)) on the microwave-reduced graphene (rGO) sheets through chemical coupling to construct a self-supporting sulfur cathode with a nano storage-box structure (V-MoS_(2) as the wall and rGO as the bottom). RGO, which has a high conductivity of 37 S cm^(−1), greatly accelerates the transfer of electrons from the active sites on the edge of the layer to the solution. The introduction of carbon tubes can connect the abundant pores in the foam and act as a long-range conductive path. The 2D-orthogonal-2D structure maximally exposes the edge active sites of MoS_(2), and together with graphene form a nano reactor of sulfur, intermediate lithium polysulfides and discharge product Li_(2)S(2). The effective combination of the microstructure confinement of the nano storage-boxes and the efficient synchronous catalytic mechanism of V-MoS_(2) greatly improves the electrochemical performance of the lithium-sulfur batteries. As a result, the assembled lithium-sulfur battery displays a high initial discharge capacity of 1379 mAh g^(−1), good cycle stability (86% capacity retention after 500 cycles at 0.1C) and superior rate performance.

关键词： Edge-rich MoS_(2) Nano boxes Catalytic conversion Lithium-sulfur batteries

Dietary habits of colorectal neoplasia patients in comparison to their first-degree relatives

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World Journal of Gastroenterology 2014年第17期20卷 5025-5030页

作者： Ivana Mikoviny Kajzrlikova petr Vitek Josef Chalupa petr Dite Beskydy Gastrocentre Department of Internal MedicineHospital Frydek-Mistek73818 Frydek-MistekCzech Republic Center of Gastroenterology Department of Internal MedicineUniversity of OstravaFaculty of Medicine70852 OstravaCzech Republic

AIM:To compare the dietary habits between colorectal neoplasia patients,their first-degree relatives,and unrelated controls.METHODS:From July 2008 to April 2011,we collected epidemiological data relevant to colorectal cancer from patients with colorectal neoplasias,their first-degree relatives,and also from a control group consisting of people referred for colonoscopy with a negative family history of colorectal cancer and without evidence of neoplasia after colonoscopic examination.The first-degree relatives were divided into two groups following the colonoscopic examination:(1)patients with neoplasia or(2)patients without neoplasia.Dietary habits of all groups were compared.Aχ2 test was used to assess the association between two dichotomous categorical variables.RESULTS:The study groups consisted of 242 patients with colorectal neoplasias(143 men,99 women;mean age:64±12 years)and 160 first-degree relatives(66men,94 women;mean age:48±11 years).Fifty-five of the first-degree relatives were found to have a neoplastic lesion upon colonoscopy,while the remaining105 were without neoplasia.The control group contained 123 individuals with a negative family history for neoplastic lesions(66 men,57 women;mean age:54±12 years).Two hypotheses were tested.In the first,the dietary habits of first-degree relatives with neoplasia were more similar to those of patients with neoplasia,while the dietary habits of first-degree relatives without neoplasia were similar to those of the control group.In the second,no sex-related differences in dietary habits were expected between the particular groups.Indeed,no significant differences were observed in the dietary habits between the groups of patients,controls and first-degree relatives with/without neoplastic lesions.Nevertheless,statistically significant sex-related differences were observed in all groups,wherein women had healthier dietary habits than men.CONCLUSION:In all groups examined,women had healthier dietary habits than men.Modification of screening guidelines according to s

关键词： Colorectal neoplasms Family Food habits Risk facto

Characterization of Curing and Bonding of Wood with Adhesive Mixtures of Liquefied Wood and Hexamethylenediamine

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Journal of Renewable Materials 2023年第2期11卷 991-1001页

作者： JureŽigon VitŠeda petrČermák MilanŠernek Department of Wood Science and Technology Biotechnical FacultyUniversity of LjubljanaLjubljana1000Slovenia Department of Wood Science and Technology Faculty of Forestry and Wood TechnologyMendel University in BrnoBrno61300Czech Republic

Various crosslinking agents can be added to the formulations of natural-based adhesives for wood bonding in order to achieve better durability and higher strength of the formed joints.In the present study,the effect of hexamethylenediamine(HMDA)addition on the performance of liquefied wood(LW)adhesive for wood bonding is investigated.Differential scanning calorimetry showed the improved thermal stability and crosslinking of the LW adhesive with HMDA.The intensified presence of amide linkages(C–N bonds)was found in LW+HMDA with attenuated total reflection Fourier transform infrared spectroscopy.Analysis of the bonded joints using an automated bonding evaluation system showed that a higher press temperature resulted in stronger bonds for both types of adhesives.Moreover,the addition of HMDA to LW adhesive improved the bond strength of the joints and accelerated the crosslinking of the adhesive.However,with a tensile shear strength of(6.76±2.16)N×mm^(−2)(for LW)and(6.89±2.10)N×mm^(−2)(for LW+HMDA),both adhesives were found to be unsuitable for interior non-structural use.In addition,the acidity of LW resulted in relatively high wood failure(70%)in the adhesive joints tested.Improved crosslinking of LW with HMDA was reflected in improved resistance of LW+HMDA adhesive joints to water degradation.In conclusion,HMDA is a promising additive for improving the adhesive performance of LW adhesives.

关键词： Adhesive bonding hexamethylenediamine liquefied wood