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A statistical analysis of geomechanical data and its effect on rock mass numerical modeling:a case study

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International Journal of Coal Science & Technology 2021年第3期8卷 312-323页

作者： piotr malkowski Zbigniew Niedbalski Tafida Balarabe Faculty of Mining and Geoengineering AGH University of Science and Technologyal.Mickiewicza 3030-059 KrakówPoland Revoult Ltd al.Jana PawlaⅡ43a31-864 KrakówPoland

Geomechanical data are never sufficient in quantity or adequately precise and accurate for design purposes in mining and civil *** objective of this paper is to show the variability of rock properties at the sampled point in the roadway's roof,and then,how the statistical processing of the available geomechanical data can affect the results of numerical modelling of the roadway's *** cases were applied in the numerical analysis,using average values(the most common in geomechanical data analysis),average minus standard deviation,median,and average value minus statistical *** study show that different approach to the same geomechanical data set can change the modelling results *** case shows that average minus standard deviation is the most conservative and least *** gives the displacements and yielded elements zone in four times broader range comparing to the average values scenario,which is the least conservative *** two other cases need to be studied *** results obtained from them are placed between most favorable and most adverse *** the average values corrected by statistical error for the numerical analysis seems to be the best ***,the confidence level can be adjusted depending on the object importance and the assumed risk level.

关键词： Statistical analysis Geotechnical data Laboratory tests on rocks Numerical modelling

Rock mass movements around development workings in various density of standing-and-roof-bolting support

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Journal of Coal Science & Engineering(China) 2008年第3期14卷 356-360页

作者： MAJCHERCZYK Tadeusz malkowski piotr NIEDBALSKI Zbigniew Faculty of Mining and Geoengineering AGH University of Science and TechnologyKrakow 30059Poland

Presented measurement results of roof rocks and wall rock movements of un- derground development workings after their *** research was carried out in the coal mine workings with standing-and-roof bolting *** were various density of the support,so the aim of the special monitoring programme was to determine movement intensity of rock mass in the premises of the heading *** were four types of re- search did by the *** measured convergence,roof layers separation using tell- tales and sonic probes and load bearing of the headings' roofs by hydraulic dynamometers Evaluation of fracture zone around the heading and investigation the load zone caused by failed roof rocks may become a basement for the determination of support parameters of the *** combined system of standing support and roof bolting seems to be an essential for underground headings protection.

关键词：岩体开采稳定性煤炭开采开采方法

Pulmonary embolism with septicemia after N-butyl-2-cyanoacrylate injection for bleeding gastric varices

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Chinese Medical Journal 2014年第16期127卷 3030-3031页

作者： Ireneusz Nawrot Tomasz Cieciura Bartlomiej Morawski piotr malkowski Jerzy Zurakowski Magdalena Durlik Department of General Vascular and Transplant Surgery Medical University of Warsaw Poland. Department of Transplantation Medicine and Nephrology Transplantation Institute Medical University of Warsaw Poland. Department of General and Transplant Surgery Transplantation Institute Medical University of Warsaw Poland. Department of General Transplant and Liver Surgery Medical University of Warsaw Poland. Department of General and Oncological Surgery Independent Public Healthcare Institution Plock Poland

Despite many advances in the treatment of gastric variceal bleeding in the two past decades, its management continues to present a clinical challenge. Various treatment modalities have been proposed and since the first report in 1986 endoscopic injection sclerotherapy with cyanoacrylate tissue adhesives has become widely established in many countries as the treatment of choice for bleeding gastric varices. Severe complications of the treatment are infrequent.

关键词： gastric varices N-butyl-2-cyanoacrylate portal hypertension

Anthropogenic noise interacts with the predation risk assessment in a free-ranging bird

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Current Zoology 2024年第3期70卷 277-283页

作者： piotr Matyjasiak Patrycja Chacińska and piotr Książka Institute of Biological Sciences Cardinal Stefan Wyszyński University in WarsawWóycickiego 1/3PL-01-815 WarsawPoland Department of Environmental Acoustics Institute of Environmental Protection—National Research InstituteKolektorska 4PL-01-692 WarsawPoland

Anthropogenic noise can affect a number of behavioral,physiological,and ecological aspects of animals from major taxonomic groups,raising serious conservation *** example,noise pollution impacts communicative behavior and perception of signals,movements and distribution,as well as predator–prey interactions,such as hunting success or predator detection and predation risk *** have carried out an experimental playback study,in which we investigated whether exposure to anthropogenic noise(sound of a tractor)distracts free-ranging barn swallows Hirundo rustica from paying attention to an approaching human“predator”(the“cognitive distraction”hypothesis),or whether noise leads to increased responsiveness to this“predator”(the“increased threat”hypothesis).The subjects were male barn swallows attending their breeding territories during the time when the females were *** found that barn swallow males initiated fight at signifcantly greater distances to the approaching human“predator”in the noise treatment than during the quiet control *** results suggest that anthropogenic noise causes increased vigilance and reactivity rather than a distraction,enabling birds to avoid the“predator”more *** further discuss the mechanism behind the increased alertness in response to noise and contrast the“increased threat”mechanism,usually tested in previous studies,with an alternative“cognitive sensitization”mechanism.

关键词： anthropogenic noise barn Swallow cognitive distraction flight initiation distance Hirundo rustica predation risk assessment

Effects of small molecules on neurogenesis:Neuronal proliferation and differentiation

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Acta Pharmaceutica Sinica B 2024年第1期14卷 20-37页

作者： MichałK Jastrze˛bski piotr Wo´jcik piotr Ste˛pnicki Agnieszka A.Kaczor Department of Synthesis and Chemical Technology of Pharmaceutical Substances with Computer Modeling Laboratory Medical University of LublinFaculty of PharmacyLublin PL-20093Poland School of Pharmacy University of Eastern FinlandKuopio FI-70211Finland

Neurons are believed to be non-proliferating ***,neuronal stem cells are still present in certain areas of the adult brain,although their proliferation diminishes with *** as with other cells,their proliferation and differentiation are modulated by various *** mechanisms are foundational to the strategies developed to induce neuronal proliferation and differentiation,with potential therapeutic applications for neurodegenerative *** most common among these diseases are Parkinson's disease and Alzheimer's disease,associated with the formation ofβ-amyloid(Aβ)aggregates which cause a reduction in the number of *** such as LiCl,4-aminothiazoles,Pregnenolone,ACEA,harmine,D2AAK1,methyl 3,4-dihydroxybenzoate,and shikonin may induce neuronal proliferation/differentiation through the activation of pathways:MAPK ERK,PI3K/AKT,NFκB,Wnt,BDNF,and ***,combinations of these compounds can potentially transform somatic cells into *** transformation process involves the activation of neuron-specific transcription factors such as NEUROD1,NGN2,ASCL1,and SOX2,which subsequently leads to the transcription of downstream genes,culminating in the transformation of somatic cells into *** diseases are not the only conditions where inducing neuronal proliferation could be ***,the impact of pro-proliferative compounds on neurons has also been researched in mouse models of Alzheimer's disease.

关键词： Neurogenesis Proliferation Differentiation Maturation Small-molecules Drug coctail Alzheimer’s disease Parkinson’s disease

Odd-even effects in the structure and properties of aryl-substituted aliphatic self-assembled monolayers

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Nano Research 2024年第5期17卷 4231-4243页

作者： piotr Cyganik Andreas Terfort Michael Zharnikov Jagiellonian University Faculty of PhysicsAstronomy and Applied Computer ScienceSmoluchowski Institute of PhysicsŁojasiewicza 1130-348 KrakówPoland Institut für Anorganische und Analytische Chemie Universität FrankfurtMax-von-Laue-Straße 760438 FrankfurtGermany Applied Physical Chemistry Heidelberg UniversityIm Neuenheimer Feld 25369120 HeidelbergGermany

Self-assembled monolayers(SAMs)represent an important tool in context of nanofabrication and molecular engineering of surfaces and *** properties of functional SAMs depend not only on the character of the tail groups at the SAM-ambient interface,but are also largely defined by their *** its turn,the latter parameter results from a complex interplay of the structural forces and a variety of other factors,including so called odd-even effects,*** of the SAM structure and properties on the parity of the number(odd or even)of individual building blocks in the backbone of the SAM *** most impressive manifestation of the odd-even effects is the structure of aryl-substituted alkanethiolate SAMs on Au(111)and Ag(111),in which,in spite of the fact that the intermolecular interaction is mostly determined by the aryl part of the monolayers,one observes a pronounced dependence of molecular inclination and,consequently,the packing density of the SAM-forming molecules on the parity of number of methylene units in the alkyl *** we review the properties of the above systems as well as address fundamental reasons behind the odd-even effects,including the existence of a so-called bending potential,which is frequently disregarded in analysis of the structure-building *** generality of the odd-even effects in SAMs is additionally supported by the recent data for SAMs on GaAs,scanning tunneling microscopy data for SAMs on Ag(111),and the data for the monolayers with selenolate and carboxyl anchoring groups on Au(111)and Ag(111).The implications of these effects in terms of the control over the packing density and orientation of the tail groups at the SAM-ambient interface,structural perfection,polymorphism,temperature-driven phase transitions,and SAM stability toward such factors as ionizing radiation,exchange reaction,and electrochemical desorption are *** implications place the odd-even effects as an important tool

关键词： self-assembled monolayers molecular films surface and interface engineering odd-even-effects

Early response of understory vegetation to the mass dieback of Norway spruce in the European lowland temperate forest

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Forest Ecosystems 2024年第2期11卷 214-225页

作者： Jan Marek Matuszkiewicz Andrzej N.Affek piotr Zaniewski Ewa Kołaczkowska Faculty of Geography and Regional Studies University of WarsawPoland Institute of Geography and Spatial Organization Polish Academy of SciencesPoland Institute of Forest Sciences Warsaw University of Life SciencesPoland

Spruce-dominated forests are commonly exposed to disturbances associated with mass occurrences of bark *** dieback of trees triggers many physical and chemical processes in the ecosystem resulting in rapid changes in the vegetation of the lower forest *** aimed to determine the response of non-tree understory vegetation to the mass dieback of Norway spruce(Picea abies)in the first years after the disturbance caused by the European spruce bark beetle(Ips typographus)*** study area was the Białowieża Biosphere Reserve covering the Polish part of the emblematic Białowieża Forest,in total 597km^(2).The main data source comprised 3,900 phytosociological relevés(combined spring and summer campaigns)collected from 1,300 systematically distributed forest sites in 2016–2018–the peak years of the bark beetle *** found that the understory responded immediately to mass spruce dieback,with the most pronounced changes observed in the year of the disturbance and the subsequent ***-tolerant forest species declined in the initial years following the mass spruce dieback,while hemicryptophytes,therophytes,light-demanding species associated with non-forest seminatural communities,as well as water-demanding forest species,*** acetosella,the most common understory species in the Białowieża Forest,showed a distinct fluctuation pattern,with strong short-term expansion right after spruce dieback,followed by a gradual decline over the next 3–4 years to a cover level 5 percentage points lower than before the ***,our study revealed that mass spruce dieback selectively affects individual herb species,and their responses can be directional and non-directional(fluctuation).Furthermore,we demonstrated that the mass dieback of spruce temporarily increases plant species diversity(α-diversity).

关键词： Forest disturbance Bark beetle outbreak Picea abies Ips typographus Response of understory vegetation Herbaceous species Biaowieza Forest

Role of gut-liver axis and glucagon-like peptide-1 receptor agonists in the treatment of metabolic dysfunction-associated fatty liver disease

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World Journal of Gastroenterology 2024年第23期30卷 2964-2980页

作者： Jakub Rochoń piotr Kalinowski Ksenia Szymanek-Majchrzak MichałGrąt Department of General Transplant and Liver SurgeryMedical University of WarsawWarsaw 02-097Poland Department of Medical Microbiology Medical University of WarsawWarsaw 02-004Poland

Metabolic dysfunction-associated fatty liver disease(MAFLD)is a hepatic manifestation of the metabolic *** is one of the most common liver diseases worldwide and shows increasing prevalence rates in most *** is a progressive disease with the most severe cases presenting as advanced fibrosis or cirrhosis with an increased risk of hepatocellular *** microbiota play a significant role in the pathogenesis and progression of MAFLD by disrupting the gut-liver *** mechanisms involved in maintaining gut-liver axis homeostasis are *** critical aspect involves preserving an appropriate intestinal barrier permeability and levels of intestinal lumen metabolites to ensure gutliver axis *** increase in intestinal barrier permeability induces metabolic endotoxemia that leads to ***,alterations in the absorption of various metabolites can affect liver metabolism and induce liver steatosis and ***-like peptide-1 receptor agonists(GLP-1 RAs)are a class of drugs developed for the treatment of type 2 diabetes *** are also commonly used to combat obesity and have been proven to be effective in reversing hepatic *** mechanisms reported to be involved in this effect include an improved regulation of glycemia,reduced lipid synthesis,β-oxidation of free fatty acids,and induction of autophagy in hepatic ***,multiple peptide receptor agonists have been introduced and are expected to increase the effectiveness of the treatment.A modulation of gut microbiota has also been observed with the use of these drugs that may contribute to the amelioration of *** review presents the current understanding of the role of the gutliver axis in the development of MAFLD and use of members of the GLP-1 RA family as pleiotropic agents in the treatment of MAFLD.

关键词： Metabolic dysfunction-associated fatty liver disease Metabolic dysfunction-associated steatohepatitis Nonalcoholic fatty liver disease Non-alcoholic steatohepatitis Metabolic syndrome Obesity Gastrointestinal microbiota Glucagon-like peptide-1 Glucagon-like peptide-2 Bariatric surgery

A dual-beam piezo-magneto-elastic wake-induced vibration energy harvesting system for high-performance wind energy harvesting

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Science China(Technological Sciences) 2024年第1期67卷 221-239页

作者： MA XiaoQing ZHANG Hang MARGIELEWICZ Jerzy GĄSKA Damian WOLSZCZAK piotr LITAK Grzegorz ZHOU ShengXi School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Research&Development Institute in Shenzhen Northwestern Polytechnical UniversityShenzhen 518057China Faculty of Transport and Aviation Engineering Silesian University of TechnologyKrasińskiego 8Katowice 40-019Poland Department of Automation Lublin University of TechnologyNadbystrzycka 36Lublin 20-618Poland

Wind-induced vibration energy harvesting has a great potential for utilizing wind energy to supply power for low-powered *** improve the working performance of energy harvesters effectively,a suitable structural design is *** paper proposes a dual-beam piezo-magneto-elastic wake-induced vibration energy harvesting system to enhance the functional performance of aeroelastic energy harvesters in environments with variable wind *** system contains two piezoelectric beams coupled by magnets(forming upstream and downstream energy harvesters),and each beam is attached with a foam cylinder.A corresponding dynamic model is provided,and output characteristics are obtained at different wind *** and experimental verification indicate that both upstream and downstream energy harvesters can realize efficient energy *** the wind speed exceeds a certain critical value,the amplitudes of the system’s displacement and voltage are *** wind speed threshold value is approximately 1.25 m/*** the wind speed and magnet spacing are 10.2 m/s and 20 mm,respectively,the output power of the system reaches 4.9×10^(−4)***,the wind speed threshold value of the proposed system can be adjusted by an equivalent nonlinear restoring force.

关键词： dual-beam structure piezoelectric energy harvester theoretical model nonlinear dynamics