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Meta-analysis of 21st century studies shows that deforestation induces profound changes in soil characteristics, particularly soil organic carbon accumulation

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FOREST ECOSYSTEMS 2025年第1期12卷 46-55页

作者： Mgelwa, Abubakari Said Ngaba, Mbezele Junior Yannick Hu, Bin Gurmesa, Geshere Abdisa Mwakaje, Agnes Godfrey Nyemeck, Mateg Pascale Bernadette Zhu, Feifei Qiu, Qingyan Song, Linlin Wang, Yingying Fang, Yunting Rennenberg, heinz Chinese Acad Sci Inst Appl Ecol CAS Key Lab Forest Ecol & Management Shenyang 110016 Peoples R China Key Lab Stable Isotope Tech & Applicat Shenyang 110016 Peoples R China Mwalimu Julius K Nyerere Univ Agr & Technol Coll Nat Resources Management & Tourism POB 976 Musoma Tanzania Southwest Univ Coll Resources & Environm Ctr Mol Ecophysiol CMEP Chongqing 400715 Peoples R China Univ Ebolowa HTTTC Higher Tech TeacherTraining Coll Ebolowa Ebolowa 886 Cameroon Multipolar Consulting Firm Yaounde 1092 Cameroon Chinese Acad Sci Qingyuan Forest CERN Shenyang 110016 Peoples R China Fujian Agr & Forestry Univ Coll Forestry Forest Ecol Stable Isotope Ctr Fuzhou 350002 Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China

Deforestation is one of the most serious environmental problems facing humankind. It continues to escalate rapidly across many regions of the world, thereby deteriorating the forest soil quality. This has prompted a large number of field-based studies aimed at understanding the impacts of deforestation on soil properties. However, the lack of comprehensive meta-analyses that utilized these studies has limited our deeper understanding of how different soil properties, including the soil organic carbon (SOC) pool, respond to deforestation. To address this critical knowledge gap, we conducted a meta-analysis of 144 studies to explore the impacts of deforestation on soil chemical, physical, and biological properties, with special emphasis on the long-term changes in SOC, such as concentrations, stocks, and sequestration. The results revealed that deforestation significantly decreased soil organic matter, electrical conductivity, and base saturation by 52%, 50%, and 98%, respectively. While deforestation increased soil total nitrogen content and decreased available phosphorus content by 51% and 99%, respectively, it resulted in slight decreases in some chemical properties, including soil pH (1%) and base cations (1%-13%). Deforestation significantly increased bulk density by 27% and soil erosion by 47%, but significantly decreased soil aggregate stability by 39% and saturated hydraulic conductivity by 63%. Soil microbial biomass C and N concentrations and enzyme activities were significantly decreased as a consequence of deforestation. Soil biological properties were much more affected by deforestation than soil physical and chemical properties. Regarding the SOC, the land use conversion from forest to pasture significantly increased SOC concentrations, stocks, and sequestration rates (11%-13%), whereas the land use conversions from forest to both plantation and cropland significantly decreased SOC concentrations, stocks, and sequestration rates (10%-43%). This observed

关键词： Deforestation Land-use change Soil properties Soil organic carbon

Quasiresiduals in Semigroups with Natural Partial Order

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Algebra Colloquium 2017年第3期24卷 361-380页

作者： heinz Mitsch Fakul t für Mathematik Universit t Wien Oskax Morgenstern Platz 1 A-1090 Wien Austria

A semigroup （S, .） is called right （left） quasiresiduated if for any a, b in S there exists x in S such that ax≤s b （xa≤s b） with respect to the natural partial order ≤s of S. This concept has its origin in the theory of residuated semigroups, but can also be seen as a generalization of the right （left） simplicity of semigroups. It is first studied for totally-, resp., trivially-ordered semigroups, and then for semigroups with idempotents. In particular, the cases when （S≤s） is directed downwards and when S contains a zero （with respect to a more restrictive definition） are dealt with. Throughout, examples are given; in total, 30 classes of （often well-known） semigroups of this kind are specified.

关键词： semigroup natural partial order quasiresidual

Premotor Diagnosis of Parkinson's Disease

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Neuroscience Bulletin 2017年第5期33卷 526-534页

作者： heinz Reichmann Department of Neurology Dresden University of Technology Fetscherstraβe 74 01307 Dresden Germany

Typical Parkinsonian symptoms consist of bradykinesia plus rigidity and/or resting tremor. Some time later postural instability occurs. Pre-motor symptoms such as hyposmia, constipation, REM sleep behavior disorder and depression may antecede these motor symp- toms for years. It would be ideal, if we had a biomarker which would allow to predict who with one or two of these pre-motor symptoms will develop the movement disorder Parkinson＇s disease （PD）. Thus, it is interesting to learn that biopsies of the submandibular gland or colon biopsies may be a means to predict PD, if there is a high amour of abnormally folded alpha-synuclein and phosphorylated alpha-synuclein. This would be of relevance if we would have available means to stop the propagation of abnormal alpha-synuclein which is otherwise one of the reasons of this spreading disease PD.

关键词： Parkinson's disease Gut-brain-axis Premotorsymptoms Hyposmia. Constipation REM sleep behavior disorder

Resolvent Estimates and Quantification of Nonlinear Stability

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Acta Mathematica Sinica,English Series 2000年第1期16卷 1-20页

作者： heinz-Otto Kreiss Jens Lorenz Department of Mathematics UCLALos AngelesCA 90095USA Department of Mathematics and Statistics UNMAlbuquerqueNM 87131USA

The aim of this paper is to clarify the role played by resolvent estimates for nonlinear *** will give examples showing that a large resolvent may lead to a small domain of nonlinear *** other examples the resolvent is large,but the domain of nonlinear stability is completely *** case prevails depends on the details of the problem. We will also show that the size of the resolvent depends in an essential way on the norms that are used.

关键词： Resolvent estimates Nonlinear stability Pseudospectrum Convection-dominated flow

Improvement of the Corrosion Resistance of High Alloyed Austenitic Cr-Ni-Mo Stainless Steels by Solution Nitriding

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材料热处理学报 2004年第5期25卷 316-321页

作者： Christine Eckstein heinz- Joachim Spies Jochen Albrecht Dept. of Materials Eng. Technische Universitat Bergakademie Freiberg 09599 Freiberg/GermanyDept. of Materials Eng. Technische Universitat Bergakademie Freiberg 09599 Freiberg/GermanyInstitut Fresenius GmbH Solid State Analytic Zur Wetterwarte 10Haus 107 01109 Dresden Germany

Characteristic features of austenitic steel grades combine a good corrosion resistance with a low hardness, wear resistance and scratch resistance. An interesting possibility for improving the wear behaviour of these steels without loss of their corrosion resistance lies in enriching the near surface region with nitrogen. The process of a solution nitriding allows the rise of the solution of nitrogen in the solid phase. On this state nitrogen increases the corrosion resistance and the tribilogical load-bearing capacity. The aim of the study was, to investigate the improvement of the pitting corrosion behaviour by solution nitriding. A special topic was to observe the effect of nitrogen by different molybdenum content. So austenitic stainless steels (18% Cr, 12% Ni, Mo gradation between 0.06 to 3.6%) had been solution nitrided. The samples could be prepared with various surface content of nitrogen from 0.04 to 0.45% with a step-by-step grinding. The susceptibility against pitting corrosion of these samples had been tested by determination of the stable pitting potential in 0.5M and 1M NaCl at 25°C. For the investigated steel composition and the used corrosion system there is no influence of molybdenum on the effectiveness of nitrogen. The influence of nitrogen to all of the determined parameters can be described well by PRE = Cr + 3,3 * Mo + 25 *N. XPS analysis of the sample surfaces support the results of the pitting corrosion *** surface investigations with an acid elektolyte (0,1M HC1 + 0,4M NaCl) were performed. In this case the passivation effective nitrogen content increases markedly with rising molybdenum concentration of the steel. Obviously an interaction of Mo and N is connected with a strongly acid electrolyte.

关键词：耐蚀性奥氏体不锈钢 Cr-Ni-Mo 渗氮 PRE 稳定点蚀电位

Effects of elevated pO_3 on carbon cycle between above andbelowground organs of trees

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Journal of Environmental Sciences 2006年第5期18卷 932-936页

作者： LIU Xi-ping Rennenberg heinz Matyssek Rainer College of Life Sciences Northwest Sci-Tech University of Agriculture and Forestry Yangling 712100 China Institute of Forest Botany and Tree Physiology University Freiburg D-79110 Freiburg Germany Department of Ecopogy/Ecophysiology of Plants Technical University Munich D-85354 Freising Germany

Translocation of carbohydrate from leaves to roots via phloem and reallocation from roots to leaves via xylem regulate the allocation of carbon （C） between above and belowground organs of trees. To quantitatively analyze effects of elevated ozone concentrations pO3 on the internal cycle of C, juvenile beech and spruce were grown in phytotrons and exposed to ambient and elevated pO3 （i.e. twice-ambient O3 levels, restricted to 〈 150 ppb） for two growing seasons. The translocation of C in the phloem and xylem was quantitatively studied by investigating the phloem/xylem-loading of sugars, the differentiation of stem conductive tissue and the hourly water flow through the stem. Results in the present study shown, elevated pO3 significantly decreased C translocation from shoot to roots in beech by reducing both sugar concentration in the phloem and conductive phloem area. Elevated pO3 also significantly decreased C reallocation from the roots to the shoot in beech by reducing both of sugar concentration in the xylem and transpiration rate. The adverse effects of elevated pO3 on C translocation in the phloem and xylem, however, were small in spruce. Contrasting to beech, spruce is less sensitive to elevated pO3, regarding to phloem differentiation and sugar concentrations in the phloem and xylem.

关键词： beech carbon cycle elevated pO3 phloem spruce xylem

Ten years of a pediatric living donor liver transplantation program in Brazil

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World Journal of Transplantation 2025年第2期15卷 127-137页

作者： Marco Aurélio Farina Junior Melina Utz-Melere Carolina Soares da Silva Luiza Salgado Nader Cristine Suzana Trein Angelica Maria Lucchese Mayara Machry Rodrigo Mariano Cristina Targa Ferreira Antônio Nocchi Kalil Flávia heinz Feier Department of Hepatology and Liver Transplantation Santa Casa de Porto AlegrePorto Alegre 90050-170Brazil Department of Hepato-Biliary-Pancreatic Surgery and Liver Transplantation Irmandade Santa Casa de Misericórdia de Porto AlegrePorto Alegre 90020-090Brazil Department of Surgical Oncology Santa Rita Hospital/Santa Casa de Misericórdia de Porto AlegrePorto Alegre 90050-170Rio Grande do SulBrazil

BACKGROUND Pediatric living-donor liver transplantation is considered a safe alternative for the treatment of children with end-stage liver *** tertiary centers and specialized medical staff are necessary to ensure compatible long-term survival rates and quality-of-life for these *** To report the results and the 10-year learning curve of a pediatric living-donor liver transplantation *** We conducted a retrospective cohort study of pediatric recipients from 2013 to ***-transplant outcomes and patient survival rates were compared between two 5-year periods of the *** A total of 25 and 48 patients underwent transplantation in the first(2013-2017)and second period(2018-2023),*** vein and hepatic artery thrombosis occurred in 11(15.1%)and seven(9.6%)patients,*** complications were observed in 39 of 73 patients(53.4%).A lower warm ischemia time was observed in the second period compared to the first(32.6±8.6 minutes vs 38.4±9.8 minutes,P=0.018,respectively).Patient survival rates at 1 and 5 years were 84%in the first period and 91.7%in the second period,with no significant difference(P=0.32).CONCLUSION The reported indications and outcomes align with the current *** findings provide crucial evidence regarding the feasibility of establishing a living donor program with consistent results over time.

关键词： End-stage liver disease Liver transplant Living donor Pediatric hepatology Survival rate

Accurate simulation of surfaces and interfaces of ten FCC metals and steel using Lennard–Jones potentials

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npj Computational Materials 2021年第1期7卷 205-219页

作者： Krishan Kanhaiya Seonghan Kim Wonpil Im Hendrik heinz Department of Chemical and Biological Engineering University of Colorado at BoulderBoulderCO 80301USA Departments of Biological Sciences Chemistryand BioengineeringLehigh UniversityBethlehemPA 18015USA

The earlier integration of validated Lennard–Jones(LJ)potentials for 8 fcc metals into materials and biomolecular force fields has advanced multiple research fields,for example,metal–electrolyte interfaces,recognition of biomolecules,colloidal assembly of metal nanostructures,alloys,and *** we introduce 12-6 and 9-6 LJ parameters for classical all-atom simulations of 10 further fcc metals(Ac,Ca(α),Ce(γ),Es(β),Fe(γ),Ir,Rh,Sr(α),Th(α),Yb(β))and stainless *** parameters reproduce lattice constants,surface energies,water interfacial energies,and interactions with(bio)organic molecules in 0.1 to 5%agreement with experiment,as well as qualitative mechanical properties under standard *** are reduced up to a factor of one hundred in comparison to earlier Lennard–Jones parameters,embedded atom models,and density functional *** also explain a quantitative correlation between atomization energies from experiments and surface energies that supports parameter *** models are computationally very efficient and applicable to an exponential space of *** with a wide range of force fields such as the Interface force field(IFF),AMBER,CHARMM,COMPASS,CVFF,DREIDING,OPLS-AA,and PCFF enables reliable simulations of nanostructures up to millions of atoms and microsecond time ***-friendly model building and input generation are available in the CHARMM-GUI Nanomaterial *** a limitation,deviations in mechanical properties vary and are comparable to DFT *** discuss the incorporation of reactivity and features of the electronic structure to expand the range of applications and further increase the accuracy.

关键词： steel metals qualitative

Imaging in translational cancer research

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Cancer Biology & Medicine 2022年第11期19卷 1565-1585页

作者： Felix T.Kurz heinz-Peter Schlemmer Department of Radiology German Cancer Research CenterHeidelberg 69120Germany

This review is aimed at presenting some of the recent developments in translational cancer imaging research,with a focus on novel,recently established,or soon to be established cross-sectional imaging techniques for computed tomography(CT),magnetic resonance imaging(MRI),and positron-emission tomography(PET)imaging,including computational investigations based on machine-learning techniques.

关键词： Cancer imaging computed tomography(CT) magnetic resonance imaging(MRI) positron emission tomography(PET) cross-sectional imaging