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No tillage outperforms conventional tillage under arid conditions and following fertilization

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Soil Ecology Letters 2023年第1期5卷 137-141页

作者： stavros d.veresoglou Junjiang Chen Xuheng du Qi Fu QingLiu Geng Chenyan Huang Xilin Huang Nan Hu Yiming Hun Guolin C.Li Zhiman Lin Zhiyu Ma Yuyi Ou Shuo Qi Haitian Qin Yingbo Qiu Xibin Sun Ye Tao YiLing Tian Jie Wang Lingxiao Wu Ziwei Wu Siqi Xie Ao Yang dan Yang Chen Zeng Ying Zeng RuJie Zhang School of Ecology Sun Yat-sen UniversityGuangzhou 510006China

Reduced tillage practices present a tool that could sustainably intensify *** existing literature,however,lacks a consensus on how and when reduced tillage practices should get *** reanalyzed here an extensive dataset comparing how regular tillage practices(i.e.,conventional tillage)impacted yield of eight crops compared to stopping tillage altogether(i.e.,no-tillage practice).We observed that aridity and fertilization favored no tillage over conventional tillage whereas conventional tillage performed better under high fertility *** further show that the responses are consistent across the *** reanalysis complements the original and fills a gap in the literature questioning the conditions under which reducing tillage presents a viable alternative to common tillage practices.

关键词： Aridity Crop production Soil erosion Sustainable agriculture Tillage practices

Arbuscular Mycorrhiza Prevents Suppression of Actual Nitrification Rates in the (Myco-)Rhizosphere of Plantago lanceolata

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Pedosphere 2012年第2期22卷 225-229页

作者： S.d.veresoglou Faculty of Agriculture Laboratory of Ecology and Environmental ProtectionAristotle University of Thessaloniki

The vast majority of herbaceous plants engage into arbuscular mycorrhizal (AM) symbioses and consideration of their mycorrhizal status should be embodied in studies of plant-microbe interactions. To establish reliable AM contrasts, however, a sterilized re-inoculation procedure is commonly adopted. It was questioned whether the specific approach is sufficient for the studies targeting the bacterial domain, specifically nitrifiers, a group of autotrophic, slow growing microbes. In a controlled experiment mycorrhizal and non-mycorrhizal Plantago lanceolata were grown up in compartmentalized pots to study the AM effect on nitrification rates in the plant rhizosphere. Nitrification rates were assayed following an extensive 3-week bacterial equilibration step of the re-inoculated soil and a 13-week plant growth period in a controlled environment. Under these specific conditions, the nitrification potential levels at harvest were exceptionally low, and actual nitrification rates of the root compartment of non-mycorrhizal P. lanceolata were significantly lower than those of any other compartment. It is then argued that the specific effects should be attributed to the alleged higher growth rates of non-mycorrhizal plants that are known to occur early in the AM experiment. It is concluded that the specific experimental approach is not suitable for the study of microbes with slow growth rates.

关键词： ammonia oxidizers nitrification potential plant-microbe interaction root compartment

Incidence, risk factors and clinical outcome of multidrug-resistant organisms after heart transplantation

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World Journal of Transplantation 2024年第2期14卷 107-118页

作者： Sophia Hatzianastasiou Paraskevas Vlachos Georgios Stravopodis dimitrios Elaiopoulos Afentra Koukousli Josef Papaparaskevas Themistoklis Chamogeorgakis Kyrillos Papadopoulos Theodora Soulele despoina Chilidou Kyriaki Kolovou Aggeliki Gkouziouta Michail Bonios Stamatios Adamopoulos stavros dimopoulos Microbiology department and Infection Control Office Onassis Cardiac Surgery CenterAthens 17674Greece Heart Transplantation Unit Onassis Cardiac Surgery CenterAthens 17674Greece Cardiac Surgery Intensive Care Unit Onassis Cardiac Surgery CenterAthens 17674Greece

BACKGROUNd Transplant recipients commonly harbor multidrug-resistant organisms(MdROs),as a result of frequent hospital admissions and increased exposure to antimi-crobials and invasive *** To investigate the impact of patient demographic and clinical characteristics on MdRO acquisition,as well as the impact of MdRO acquisition on intensive care unit(ICU)and hospital length of stay,and on ICU mortality and 1-year mortality post heart *** This retrospective cohort study analyzed 98 consecutive heart transplant patients over a ten-year period(2013-2022)in a single transplantation *** was collected regarding MdROs commonly encountered in critical *** Among the 98 transplanted patients(70%male),about a third(32%)acquired or already harbored MdROs upon transplantation(MdRO group),while two thirds did not(MdRO-free group).The prevalent MdROs were Acinetobacter baumannii(14%),Pseudomonas aeruginosa(12%)and Klebsiella pneumoniae(11%).Compared to MdRO-free patients,the MdRO group was characterized by higher body mass index(P=0.002),higher rates of renal failure(P=0.017),primary graft dysfunction(10%vs 4.5%,P=0.001),surgical re-exploration(34%vs 14%,P=0.017),mechanical circulatory support(47%vs 26%P=0.037)and renal replacement therapy(28%vs 9%,P=0.014),as well as longer extracorporeal circulation time(median 210 vs 161 min,P=0.003).The median length of stay was longer in the MdRO group,namely ICU stay was 16 vs 9 d in the MdRO-free group(P=0.001),and hospital stay was 38 vs 28 d(P=0.006),while 1-year mortality was higher(28%vs 7.6%,log-rank-χ2:7.34).CONCLUSION Following heart transplantation,a predominance of Gram-negative MdROs was *** acquisition was associated with higher complication rates,prolonged ICU and total hospital stay,and higher post-transplantation mortality.

关键词： Heart transplantation Multi drug resistant organisms Transplantation complications Transplantation outcome

Effects of Nitrogen and Phosphorus Fertilization on Soil pH-Plant Productivity Relationships in Upland Grasslands of Northern Greece

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Pedosphere 2011年第6期21卷 750-752页

作者： S.d.veresoglou O.K.VOULGARI R.SEN A.P.MAMOLOS d.S.veresoglou Faculty of Agriculture Laboratory of Ecology and Environmental ProtectionAristotle University of Thessaloniki department of Environmental and Geographical Sciences Manchester Metropolitan UniversityJohn Dalton Building

The potential role of soil pH in modulating plant productivity was assessed on the basis of dry mass, harvested in the form of 0.25 m2 quadrats, in two low-productivity upland grasslands of northern Greece subjected to annual factorial nitrogen （N） and phosphorus （P） fertilization （15 g N m-2 year-1 and 10 g P m-2 year-I） over a minimum period of 3 years. It was hypothesized that under these particular conditions, a positive relationship would exist between soil pH and plant productivity and, further, that N or P fertilizer application of a nutrient limited system, would result in a weakening of this positive relationship. A significant positive relationship was confirmed between soil pH and plant productivity in one of the two study areas and a positive trend in the other. Moreover, plant productivity increase, following fertilization, appeared to have a detrimental effect on the soil pH-plant productivity relationship. Findings support the original hypotheses and strengthen the idea that plant diversity-mediated soil pH-plant productivity relationships are a result of the more intense plant speciation that occurred under the more ＂typical＂ soil conditions of higher pH in temperate as opposed to tropical regions

关键词： altitude ecological patterns low productivity grasslands temperate ecosystems

Snapshot imaging of ultrashort electron bunches

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Light(Science & Applications) 2024年第7期13卷 1226-1228页

作者： Andreas döpp Ludwig-Maximilian-Universität München Am Coulombwall 185748GarchingGermany Max Planck Institut für Quantenoptik Hans-Kopfermann-Strasse 1Garching85748Germany

New measurements combine spatial and temporal information from optical transition radiation to estimate the three-dimensional structure of electron bunches from a laser wakefield accelerator.

关键词： ultrashort Snapshot electron

Influence of variable viscosity and double diffusion on the convective stability of a nanofluid flow in an inclined porous channel

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 563-580页

作者： N.HUMNEKAR d.SRINIVASACHARYA department of Mathematics National Institute of TechnologyWarangal 506004TelanganaIndia

The influence of variable viscosity and double diffusion on the convective stability of a nanofluid flow in an inclined porous channel is *** darcyBrinkman model is used to characterize the fluid flow dynamics in porous *** analytical solutions are obtained for the unidirectional and completely developed *** on a normal mode analysis,the generalized eigenvalue problem under a perturbed state is *** eigenvalue problem is then solved by the spectral ***,the critical Rayleigh number with the corresponding wavenumber is evaluated at the assigned values of the other flow-governing *** results show that increasing the darcy number,the Lewis number,the dufour parameter,or the Soret parameter increases the stability of the system,whereas increasing the inclination angle of the channel destabilizes the ***,the flow is the most unstable when the channel is vertically oriented.

关键词： nanofluid inclined channel variable viscosity linear stability double dif-fusion porous medium

P-Tree Structures and Event Horizon： Efficient Event-Set Implementations

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Journal of Computer Science & Technology 2006年第1期21卷 19-26页

作者： Katerina Asdre stavros d. Nikolopoulos department of Computer Science University of Ioannina GR-45110 Ioannina Greece

This paper describes efficient data structures, namely the Indexed P-tree, Block P-tree, and Indexed-Block P-tree （or/P-tree, BP-tree, and IBP-tree, respectively, for short）, for maintaining future events in a general purpose discrete event simulation system, and studies the performance of their event set algorithms under the event horizon principle. For comparison reasons, some well-known event set algorithms have been selected and studied, that is, the dynamic-heap and the P-tree algorithms. To gain insight into the performance of the proposed event set algorithms and allow comparisons with the other selected algorithms, they are tested under a wide variety of conditions in an experimental way. The time needed for the execution of the Hold operation is taken as the measure for estimating the average time complexity of the algorithms. The experimental results show that the BP-tree algorithm and the IBP-tree algorithm behave very well with the event set of all the sizes and their performance is almost independent of the stochastic distributions.

关键词： discrete-event simulation event set algorithms hold model event horizon data structures heap P-tree P-tree structures

Improved Leap-frog Method for Time-domain Fault Location

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 670-674页

作者： Izudin džafić Rabih A.Jabr Faculty of Electrical Engineering University of SarajevoSarajevo 71000Bosnia and Herzegovina department of Electrical and Computer Engineering American University of BeirutBeirut 11072020Lebanon IEEE

The partial differential equation(PdE)solution of the telegrapher is a promising fault location method among time-domain and model-based *** research works have shown that the leap-frog process is superior to other explicit methods for the PdE ***,its implementation is challenged by determining the initial conditions in time and the boundary conditions in *** letter proposes two implicit solution methods for determining the initial conditions and an analytical way to obtain the boundary conditions founded on the signal *** results show that the proposal gives fault location accuracy superior to the existing leap-frog scheme,particularly in the presence of harmonics.

关键词： Fault location leap-frog partial differential equation time-domain analysis transmission line

The Effect of External Magnetic Field on Electron Scale Kelvin–Helmholtz Instability

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Research in Astronomy and Astrophysics 2024年第9期24卷 236-247页

作者： d.Tsiklauri Joule Physics Laboratory School of ScienceEngineering and EnvironmentUniversity of SalfordManchesterM54WTUK

We use particle-in-cell,fully electromagnetic,plasma kinetic simulation to study the effect of external magnetic field on electron scale Kelvin–Helmholtz instability(ESKHI).The results are applicable to collisionless plasmas when,e.g.,solar wind interacts with planetary magnetospheres or a magnetic field is generated in AGN *** find that as in the case of magnetohydrodynamic(MHd)KHI,in the kinetic regime,the presence of an external magnetic field reduces the growth rate of the *** the MHd case,there is a known threshold magnetic field for KHI stabilization,while for ESKHI this is to be analytically *** a kinetic analytical expression,we use several numerical simulation runs to establish an empirical dependence of ESKHI growth rate,Γ(B_(0))ω_(pe),on the strength of the applied external magnetic *** find the best fit is hyperbolic,Γ(B_(0))ω_(pe)=Γ_(0)ω_(pe)/(A+BB_(0)),where Γ_(0) is the ESKHI growth rate without an external magnetic field and B_(0)=B_(0)/B_(MHd)is the ratio of external and two-fluid MHd stability threshold magnetic field,derived *** analytical theory to back up this growth rate dependence on the external magnetic field is *** results suggest that in astrophysical settings where a strong magnetic field pre-exists,the generation of an additional magnetic field by the ESKHI is suppressed,which implies that nature provides a“safety valve”—natural protection not to“over-generate”magnetic field by the ESKHI ***,we find that our two-fluid MHd threshold magnetic field is the same(up to a factor √γ_(0))as the dC saturation magnetic field,previously predicted by fully kinetic theory.

关键词： instabilities magnetic fields plasmas Sun:heliosphere ISM:magnetic fields