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Addressing nonresponse bias in forest inventory change estimation using response homogeneity classifications

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Forest Ecosystems 2023年第1期10卷 125-131页

作者： James A.Westfall mark D.Nelson U.s.Forest service Northern Research StationYorkPAUSA U.s.Forest service Northern Research StationSt.PaulMNUSA

Estimating amounts of change in forest resources over time is a key function of most national forest inventories(NFI). As this information is used broadly for many management and policy purposes, it is imperative that accurate estimations are made from the survey sample. Robust sampling designs are often used to help ensure representation of the population, but often the full sample is unrealized due to hazardous conditions or possibly lack of land access permission. Potentially, bias may be imparted to the sample if the nonresponse is nonrandom with respect to forest characteristics, which becomes more difficult to assess for change estimation methods that require measurements of the same sample plots at two points in time, i.e., remeasurement. To examine potential nonresponse bias in change estimates, two synthetic populations were constructed: 1) a typical NFI population consisting of both forest and nonforest plots, and 2) a population that mimics a large catastrophic disturbance event within a forested population. Comparisons of estimates under various nonresponse scenarios were made using a standard implementation of post-stratified estimation as well as an alternative approach that groups plots having similar response probabilities(response homogeneity). When using the post-stratified estimators, the amount of change was overestimated for the NFI population and was underestimated for the disturbance population, whereas the response homogeneity approach produced nearly unbiased estimates under the assumption of equal response probability within groups. These outcomes suggest that formal strategies may be needed to obtain accurate change estimates in the presence of nonrandom nonresponse.

关键词： Disturbance Post-stratification Land use conversion sample bias

Repeated hydrogen peroxide dosing briefly reduces cyanobacterial blooms and microcystin while increasing fecal bacteria indicators in a eutrophic pond

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Journal of Environmental sciences 2023年第2期124卷 522-543页

作者： mark W.Lusty Christopher J.Gobler school of Marine and Atmospheric sciences Stony Brook UniversitySouthamptonNY 11968USA

This study explored the effects of H_(2)O_(2)on Cyanobacteria and non-target microbes using fluorometry,microscopy,flow cytometry,and high throughput DNA sequencing of the 16s rRNA gene during a series of mesocosm and whole-ecosystem experiments in a eutrophic pond in NY,*** addition of H_(2)O_(2)(8 mg/L)significantly reduced Cyanobacteria concentrations during a majority of experiments(66%;6 of 9)and significantly increased eukaryotic green and unicellular brown algae in 78%and 45%of experiments,*** heterotrophic bacteria declined significantly following H_(2)O_(2)addition in all experiments,bacteria indicative of potential fecal contamination(Escherichia coli,Enterococcus,fecal coliform bacteria)consistently and significantly increased in response to H_(2)O_(2),evidencing a form of‘pollution swapping’.H_(2)O_(2)more effectively reduced Cyanobacteria in enclosed mesocosms compared to whole-ecosystem *** whole-pond H_(2)O_(2)applications over a twoyear period temporarily reduced cyanobacterial levels but never reduced concentrations below bloom thresholds and populations always rebounded in two weeks or *** bacterial phyla of Cyanobacteria,Actinobacteria,and Planctomycetes were the most negatively impacted by H_(2)O_(2).Microcystis was always reduced by H_(2)O_(2),as was the toxin microcystin,but Microcystis remained dominant even after repeated H_(2)O_(2)*** H_(2)O_(2)favored the growth of eukaryotic algae over potentially harmful Cyanobacteria,the inability of H_(2)O_(2)to end cyanobacterial blooms in this eutrophic waterbody suggests it is a non-ideal mitigation approach in high biomass ecosystems and should be used judiciously due to potential negative impacts on non-target organisms and promotion of bacteria indicative of fecal contamination.

关键词： Indicator bacteria Toxic cyanobacteria Microcystin Microcystis Hydrogen peroxide Bacteria Enterococcus E.coli Pollution swapping

systemic right ventricle complications in levo-transposition of the great arteries: A case report and review of literature

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World Journal of Cardiology 2023年第10期15卷 542-552页

作者： Mohamed Ramzi Almajed Abdulla Almajed Naoshin Khan mark s Obri Karthikeyan Ananthasubramaniam Department of Internal Medicine Henry Ford HospitalDetroitMI 48202United States College of Medicine and Medical sciences Arabian Gulf UniversityManama 00000Bahrain Heart and Vascular Institute Henry Ford West Bloomfield HospitalWest BloomfieldMI 48322United States

BACKGROUND Congenitally corrected levo-transposition of the great arteries(L-TGA)is a congenital heart disease in which the ventricles and great arteries are transposed from their typical *** L-TGA,the double discordance,atrioventricular and ventriculoarterial,create an acyanotic milieu which allows patients to survive their early decades,however,progressive systemic right ventricle(sRV)dys-function creates complications later in *** dysfunction and remodeling predisposes patients to intracardiac thrombus(ICT)*** sUMMARY A 40-year-old male with L-TGA presented with symptoms of acute decom-pensated heart *** childhood,he had surgical repair of a ventricular septal *** adulthood,he developed sRV dysfunction,systemic tricuspid valve(sTV)regurgitation,and left-bundle branch block for which he underwent cardiac resynchronization *** echocardiogram showed a sRV ejection fraction of 40%,severe sTV regurgitation,and a newly identified sRV *** was confirmed by ultrasound-enhancing agents and transesophageal *** patient was optimized with guideline-directed medical therapy and *** was achieved with a vitamin K antagonist(VKA)and he was later referred for evaluation by advanced heart failure and heart transplant *** Anticoagulation with VKA is the mainstay of treatment in the absence of conclusive data supporting direct oral anticoagulant use in ICT in patients with congenital heart *** case illustrates the natural history of L-TGA and highlights the importance of surveillance and monitoring with dedicated cardiac imaging to identify complications.

关键词： Levo-transposition of the great arteries systemic right ventricle Congenital heart disease Intracardiac thrombus Anticoagulation Direct oral anticoagulant Case report

Modelling of grinding mechanics:A review

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Chinese Journal of Aeronautics 2023年第7期36卷 25-39页

作者： Qingyu MENG Bing GUO Qingliang ZHAO Hao Nan LI mark JJACKsON Barbara sLINKE Xichun LUO Center for Precision Engineering School of Mechatronics EngineeringHarbin Institute of TechnologyHarbin 150001China school of Aerospace The University of Nottingham NingboNingbo 315100China school of Integrated studies College of Technology and AviationKansas State UniversitySalinaKS 67401USA Department of Mechanical and Aerospace Engineering University of California DavisDavisUSA Centre for Precision Manufacturing DMEMUniversity of StrathclydeGlasgowUK

Grinding is one of the most widely used material removal methods at the end of many process *** force is related to almost all grinding parameters,which has a great influence on material removal rate,dimensional and shape accuracy,surface and subsurface integrity,thermodynamics,dynamics,wheel durability,and machining system *** that grinding force is related to almost all grinding parameters,grinding force can be used to detect grinding wheel wear,energy calculation,chatter suppression,force control and grinding process *** prediction of grinding forces is important for optimizing grinding parameters and the structure of grinding machines and *** there are substantial research papers on grinding mechanics,a comprehensive review on the modeling of grinding mechanics is still absent from the *** fill this gap,this work reviews and introduces theoretical methods and applications of mechanics in grinding from the aspects of modeling principles,limitations and possible future trendencies.

关键词： Force modeling Grinding Grinding mechanics Macro force Micro force Model application

Land use and dingo baiting are correlated with the density of kangaroos in rangeland systems

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Integrative Zoology 2023年第2期18卷 299-315页

作者： stuart J.DAWsON Tracey L.KREPLINs Malcolm s.KENNEDY Juanita RENWICK mark A.COWAN Patricia A.FLEMING Terrestrial Ecosystem science and sustainability Harry Butler InstituteMurdoch UniversityMurdochAustralia Department of Primary Industries and Regional Development(present address) South PerthAustralia Department of Primary Industries and Regional Development NorthamAustralia Queensland Department of Environment and science Australia Queensland Department of Environment and science MoggillAustralia Department of Biodiversity Conservation and AttractionsWoodvaleAustralia

Rangelands worldwide have been subject to broadscale modiﬁcation,such as widespread predator control,intro-duction of permanent livestock water and altered vegetation to improve *** Australia,these landscape changes have resulted in kangaroos(*** macropods)populations increasing over the past 200 ***-garoos are a key contributor to total grazing pressure and in conjunction with livestock and feral herbivores have been linked to land *** used 22 years of aerial survey data to investigate whether the density of 3 macropod species in the southern rangelands of Western Australia was associated with:(i)land use,including type of livestock,total livestock,density of feral goats,type of land tenure,and kangaroo commercial harvest effort;(ii)predator management,including permitted dingo control effort,estimated dingo abundance,and presence of the state Barrier Fence(a dingo exclusion fence);and(iii)environmental variables:ruggedness,rainfall,fractional cover,and total standing dry *** kangaroos(Osphranter rufus)were most abundant inﬂat,open vegetation,on pastoral land,where area permitted for dingo control was high,and numbers were positively associated with antecedent rainfall with a 12-month *** grey kangaroos(Macropus fuliginosus)were most abundant onﬂat,agricultural land,but less abundant in areas with high permitted dingo ***(Osphranter robustus)were most abundant in rugged pastoral land with open vegetation,where permitted dingo control was *** environmental variables are key drivers of landscape productivity and kangaroo populations,anthropogenic factors such as land use and permitted dingo control are strongly associated with kangaroo abundance.

关键词： herbivores livestock macropods overgrazing rangelands total grazing pressure

Design and thermodynamic analysis of a pathway enabling anaerobic production of poly-3-hydroxybutyrate in Escherichia coli

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synthetic and systems Biotechnology 2023年第4期8卷 629-639页

作者： Karel Olavarria Marco V.Becker Diana Z.sousa mark C.M.van Loosdrecht s.Aljoscha Wahl Laboratory of Microbiology Wageningen University and ResearchStippenenweg 46708 WEWageningenThe Netherlands Centre for Living Technologies Eindhoven-Wageningen-Utrecht AlliancePrincetonlaan 63584 CBUtrechtThe Netherlands Department of Biotechnology Applied Sciences FacultyDelft University of Technologyvan der Maasweg 92629 HZDelftThe Netherlands Lehrstuhl für Bioverfahrenstechnik Friedrich-Alexander-Universit¨atPaul-Gordan-Strasse 391052ErlangenGermany

Utilizing anaerobic metabolisms for the production of biotechnologically relevant products presents potential advantages,such as increased yields and reduced energy ***,lower energy dissipation may indicate that certain reactions are operating closer to their thermodynamic *** stoichiometric analyses and genetic modifications are frequently employed in metabolic engineering,the use of thermodynamic tools to evaluate the feasibility of planned interventions is less *** this study,we propose a novel metabolic engineering strategy to achieve an efficient anaerobic production of poly-(R)-3-hydroxybutyrate(PHB)in the model organism Escherichia *** approach involves re-routing of two-thirds of the glycolytic flux through non-oxidative glycolysis and coupling PHB synthesis with NADH *** complemented our stoichiometric analysis with various thermodynamic approaches to assess the feasibility and the bottlenecks in the proposed engineered *** to our calculations,the main thermodynamic bottleneck are the reactions catalyzed by the acetoacetyl-CoAβ-ketothiolase(EC 2.***.1.9)and the acetoacetyl-CoA reductase(EC 1.***.1.36).Furthermore,we calculated thermodynamically consistent sets of kinetic parameters to determine the enzyme amounts required for sustaining the conversion *** the case of the engineered conversion route,the protein pool necessary to sustain the desired fluxes could account for 20%of the whole cell dry weight.

关键词： Pathway feasibility analysis Protein cost Anaerobic metabolism Engineered pathways Metabolite concentrations

Erroneous use of statistics behind Claims of a Major solar Role in Recent Warming

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Research in Astronomy and Astrophysics 2022年第12期22卷 224-231页

作者： mark T.Richardson Rasmus E.Benestad Jet Propulsion Laboratory California Institute of TechnologyPasadenaCA 91109USA Department of Atmospheric science Colorado State UniversityFt CollinsCO 90732USA Norwegian Meteorological Institute NO-0313 OsloNorway

In a study that attempted to relate solar and human activity to Earth's recent temperature change,Connolly et *** a basic error in the choice of statistical methods and so overreported the effect of the sun.A major theme of their study was that there are many data sets of past solar activity,and some of these allegedly provide statistical evidence of“most of the recent global warming being due to changes in solar activity.”We avoid methods that are known to give inaccurate results and show that for 1970–2005 Northern Hemisphere land the corrected solar attribution fraction is-7%to+5%,compared with values of up to 64%reported in Connolly et *** higher values are entirely due to mistaken application of ***,we cannot test truly“recent”global warming since most of their solar data sets end before 2015,and two finish in the 1990s,but all tested post-1970 periods show similarly small solar *** solar-climate linkage is an area of fascinating and ongoing research with rigorous technical *** argue that instead of repeating errors,they should be acknowledged and corrected so that the debate can focus on areas of legitimate scientific uncertainty.

关键词： Earth (sun:)solar-terrestrial relations Physical Data and Processes

Modeling hydrologic responses using multi-site and single-site rainfall generators in a semi-arid watershed

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International soil and Water Conservation Research 2022年第2期10卷 177-187页

作者： Ying Zhao mark A.Nearing David Phillip Guertin state Key Laboratory of simulation and Regulation of the Water Cycle in River Basins China Institute of Water Resources and Hydropower ResearchBeijing100048China UsDA-Agricultural Research service Southwest Watershed Research CenterTucsonAZ85719USA school of Natural Resources and the Environment University of ArizonaTucsonAZ85719USA

Hydrologic response in a watershed is driven by ***-site rainfall generators can be used to model watersheds using spatially varied rainfall inputs to better analyze how the rainfall variability affects runoff *** study adopted both a single-site rainfall generator(CLIGEN)and a multi-site rainfall generator to generate two rainfall data sequences,which were then used to drive the soil and Water Assessment Tool(sWAT)for runoff *** 148-km2 Walnut Gulch Experimental Watershed and its two sub-watersheds were selected to evaluate the hydrologic *** calibration was done against measured runoff in the *** showed that the single-site and multi-site rainfall generators gave similar results regarding annual ***,the multi-site generator performed much better than the single-site generator in both mean summer flow and for the different return period *** runoff derived from the single-site generator was significantly over-estimated in all three *** for the multi-site generator,the derived runoff was satisfactorily predicted in the smaller watersheds but only overestimated in the largest *** indicated that in small to medium sized watersheds,the spatial variability of rainfall could play an important role for hydrologic response because of the heterogeneity of convective rainfall in this semi-arid region,which makes the application of multi-site rainfall generator a better option than the single-site generator.

关键词： Rainfall generator Hydrologic response Watershed modeling semi-arid spatial variability Runoff

Assessing the impact of conceptual mineral systems uncertainty on prospectivity predictions

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Geoscience Frontiers 2022年第6期13卷 182-207页

作者： mark D Lindsay Agnieszka M.Piechocka mark W Jessell Richard scalzo Jeremie Giraud Guillaume Pirot Edward Cripps Commonwealth scientific and Industrial Research Organisation Mineral Resources Australian Resources Research CentreWA 6151Australia Mineral Exploration Cooperative Research Centre Centre for Exploration TargetingSchool of Earth SciencesThe University of Western AustraliaPerthWA 6009Australia ARC Centre for Data Analytics for Resources and Environments(DARE) Perth and SydneyAustralia University of sydney School of Mathematics and StatisticsSydneyAustralia Universitéde Lorraine GeoRessourcesCNRS54000 NancyFrance The University of Western Australia Department of Mathematics and StatisticsPerthAustralia

The past two decades have seen a rapid adoption of artificial intelligence methods applied to mineral exploration. More recently, the easier acquisition of some types of data has inspired a broad literature that has examined many machine learning and modelling techniques that combine exploration criteria,or ’features’, to generate predictions for mineral prospectivity. Central to the design of prospectivity models is a ’mineral system’, a conceptual model describing the key geological elements that control the timing and location of economic mineralisation. The mineral systems model defines what constitutes a training set, which features represent geological evidence of mineralisation, how features are engineered and what modelling methods are used. Mineral systems are knowledge-driven conceptual models, thus all parameter choices are subject to human biases and opinion so alternative models are ***, the effect of alternative mineral systems models on prospectivity is rarely compared despite the potential to heavily influence final predictions. In this study, we focus on the effect of conceptual uncertainty on Fe ore prospectivity models in the Hamersley region, Western Australia. Four important considerations are tested.(1) Five different supergene and hypogene conceptual mineral systems models guide the inputs for five forest-based classification prospectivity models model.(2) To represent conceptual uncertainty, the predictions are then combined for prospectivity model comparison.(3)Representation of three-dimensional objects as two-dimensional features are tested to address commonly ignored thickness of geological units.(4) The training dataset is composed of known economic mineralisation sites(deposits) as ’positive’ examples, and exploration drilling data providing ’negative’sampling locations. Each of the spatial predictions are assessed using independent performance metrics common to AI-based classification methods and subjected to geological pl

关键词： Uncertainty Modelling Prospectivity Economic geology Geological plausibility Forest-based classification