Soil Structure,its Development and its Implications for Properties and Processes in Soils - a synopsis based on recent research in Germany     

Karl Heinrich Hartge 《植物养料与土壤学杂志》1994,157(3):159-164

In a synoptic way the development of soil structure and its effects on processes in soils are treated, referring on more recent results of investigations in Germany. It is outlined that development of structure is an absolutely primary part of soil development which basically consists of the phenomena of loosening-versus-compaction and heterogenisation-versus-homogenisation. The process of aggregation is described together with its abiotic and biotic mechanisms and its consequences for the pore system and the processes which are influenced by it. A number of examples is given for the wide variety of mechanisms, chemisms and biologic processes which are influenced by soil structure and its change.  相似文献   

Zur Auswirkung organischer Substanz verschiedener Humifizierungsgrade auf die Aggregatstabilität durch Reduzierung der Benetzbarkeit     

Haiquan Zhang  Karl Heinrich Hartge 《植物养料与土壤学杂志》1992,155(2):143-149

Effect of differently humified organic matter on aggregate stability by reducing aggregate wettability The subject of this study was to examine the significance of the contribution of organic matter to the aggregate stability against slaking by reducing aggregate wettability. Artificial spherical aggregates were formed from about 50 g paste each of a loessial (B_t-horizon) and of a clayey soil (P-horizon), which were then coated with ground peat moss (strongly and slightly humified). The slaking behavior of the air-dry aggregates was determined by measuring the water infiltration rate and the aggregate breakdown as a function of time. The results show, not only the water infiltration rate but also the aggregate breakdown were slowed down in presence of the organic coating. This effect of organic matter increased with increasing huminification. The fragments derived from aggregates with organic coating were significantly larger than those from aggregates without organic coating. The main reason for this difference is the reduced water infiltration rate into aggregates, so that the aggregates break down rather slowly and progressively than explosively. It plays an important role, that because of the wetting inhibition at the beginning the distance is longer and/or the resistance is greater for the further water infiltration into the aggregates with organic coating than those into the aggregates without organic coating. The organic matter would possibly also be transported into the inside of the aggregates by water flux.  相似文献   

Ethical Guidelines for Publication in Journals     

Almut Beate Heinrich 《Journal of Soils and Sediments》2006,6(3):125-127

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Transrectal Doppler sonography of uterine blood flow during the first two weeks after parturition in Simmenthal heifers     

Maike Heppelmann  Lars Krüger  Stephanie Leidl  Heinrich Bollwein 《Journal of veterinary science (Suw?n-si, Korea)》2013,14(3):323-327

Transrectal Doppler sonography was used to evaluate uterine blood flow during the first two weeks after parturition in six primiparous Simmental cows. The uterine blood flow was evaluated on the day of parturition (Day 0), once daily from Days 1 to 8 and then every other day until Day 14. Blood flow was quantified by determining the diameter (D), the time-averaged maximum velocity (TAMV), the pulsatility index (PI) and the blood flow volume (BFV) of the uterine arteries ipsilateral and contralateral to the formerly pregnant uterine horn. During the first four days after calving D, TAMV and BFV declined (ipsilateral: TAMV 70%, BFV 87%, contralateral: D 47%, BFV 84%; p < 0.05), while PI increased (ipsilateral 158%, contralateral 100%; p < 0.05) distinctly. Between Days 4 and 14 only the ipsilateral D (12%) and the BFV of both arteries (ipsilateral 5%, contralateral 8%) decreased (p < 0.05). Blood flow variables were very strongly correlated with each other (r > ±0.75, p < 0.05), with negative correlations with PI and positive correlations with all other investigated factors. Overall, this study revealed characteristic changes in uterine perfusion during the first two weeks after parturition in cows that were pronounced during the first four days postpartum.  相似文献   

Brucellosis in camels     

Gwida M  El-Gohary A  Melzer F  Khan I  Rösler U  Neubauer H 《Research in veterinary science》2012,92(3):351-355

Camels are highly susceptible to brucellosis caused by Brucella melitensis and Brucella abortus. Difficulties can arise in diagnosis of camel brucellosis, especially as this disease provokes only few clinical signs in contrast to its clinical course in cattle. Because none of the commonly used serological test can be perceived as a perfect test for Brucella diagnosis in camel and most serological tests used for camels have been directly transposed from cattle without adequate validation, an incorrect diagnosis may occur when diagnosis is based on serology alone. Of imminent concern is the fact that brucellosis can be easily transmitted from animals or their products to humans mainly via milk. In many developing countries in the arid areas of Asia and Africa, camels are still the most important productive livestock for nomadic populations. Therefore, we reviewed the literatures on camel brucellosis to highlight the epidemiologic, economic and public health impact of camel brucellosis as a basis for designing effective control strategies.  相似文献   

Clinical Consequences of Hypertriglyceridemia‐Associated Proteinuria in Miniature Schnauzers          下载免费PDF全文

R.E. Smith  J.L. Granick  C.D. Stauthammer  D.J. Polzin  D.A. Heinrich  E. Furrow 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2017,31(6):1740-1748

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Ocular biometry by computed tomography in different dog breeds          下载免费PDF全文

Carolin L. H. Chiwitt  Stephen J. Baines  Paul Mahoney  Andrew Tanner  Christine L. Heinrich  Michael Rhodes  Heidi J. Featherstone 《Veterinary ophthalmology》2017,20(5):411-419

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Combining isotopic signatures of n(Sr)/n(Sr) and light stable elements (C,N, O,S) with multi-elemental profiling for the authentication of provenance of European cereal samples     

Daniel Goitom Asfaha  Christophe R. Quétel  Freddy Thomas  Micha Horacek  Bernhard Wimmer  Gerhard Heiss  Christian Dekant  Peter Deters-Itzelsberger  Stefan Hoelzl  Susanne Rummel  Christophe Brach-Papa  Marleen Van Bocxstaele  Eric Jamin  Malcolm Baxter  Katharina Heinrich  Simon Kelly  Daniela Bertoldi  Luana Bontempo  Federica Camin  Roberto Larcher  Matteo Perini  Andreas Rossmann  Antje Schellenberg  Claus Schlicht  Heinz Froeschl  Jurian Hoogewerff  Henriette Ueckermann 《Journal of Cereal Science》2011

The aim of this work (from the FP6 project TRACE) was to develop methods based on the use of geochemical markers for the authentication of the geographical origin of cereal samples in Europe (cf. EC regulations 2081/92 and 1898/06). For the first time, the potential usefulness of combining n(⁸⁷Sr)/n(⁸⁶Sr) and δ¹³C, δ¹⁵N, δ¹⁸O and δ³⁴S isotopic signatures, alone or with key element concentrations ([Na], [K], [Ca], [Cu] and [Rb], progressively identified out of 31 sets of results), was investigated through multiple step multivariate statistics for more than 500 cereal samples collected over 2 years from 17 sampling sites across Europe representing an extensive range of geographical and environmental characteristics.  相似文献   

Measurement of fast electron spin relaxation times with atomic resolution     

Loth S  Etzkorn M  Lutz CP  Eigler DM  Heinrich AJ 《Science (New York, N.Y.)》2010,329(5999):1628-1630

Single spins in solid-state systems are often considered prime candidates for the storage of quantum information, and their interaction with the environment the main limiting factor for the realization of such schemes. The lifetime of an excited spin state is a sensitive measure of this interaction, but extending the spatial resolution of spin relaxation measurements to the atomic scale has been a challenge. We show how a scanning tunneling microscope can measure electron spin relaxation times of individual atoms adsorbed on a surface using an all-electronic pump-probe measurement scheme. The spin relaxation times of individual Fe-Cu dimers were found to vary between 50 and 250 nanoseconds. Our method can in principle be generalized to monitor the temporal evolution of other dynamical systems.  相似文献   

Isolation and partial characterization of an antifungal protein from the endophytic Bacillus subtilis strain EDR4     

Bing Liu  Heinrich Buchenauer 《Pesticide biochemistry and physiology》2010,98(2):305-311

An antifungal protein E2, from the culture filtrate of the endophytic Bacillus subtilis strain EDR4 of wheat with a high activity against numerous fungal species in vitro and take-all in wheat caused by Gaeumannomyces graminis var. tritici in vivo, was purified by (NH₄)₂SO₄ precipitation, hydrophobic-interaction chromatography, anion-exchange chromatography and polyacrylamide gel electrophoresis (PAGE). The molecular mass of the protein was about 377.0 kDa determined by gel permeation chromatography (GPC) using a Superdex 200 10/300 GL pre-packed column and the pI value of the protein detected by isoelectric focusing PAGE was 6.59. Following sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) the antifungal protein showed a band with a molecular mass of 39.1 kDa, which suggest that the native protein consists of multi-subunits. The amino acid sequences of three peptides from the antifungal protein were obtained by using a nano-ESI-MS/MS (Q-TOF2) System. The protein isolated may be regarded as a new protein according to amino acid sequences of three peptides. The purified protein exhibited inhibitory activity on mycelium growth of e.g. Fusarium graminearum, Macrophoma kuwatsukai, Rhizoctonia cerealis, Fusarium oxysporum f.sp. vasinfectum, Botrytis cinerea and G. graminis var. tritici (Ggt). Scanning electron microscopy showed that hyphae of Ggt treated with the antifungal protein were severely deformed. The antifungal protein E2 exhibited ribonuclease and hemagglutinating activities as well as a trifle protease activity. However, no β-1,3-glucanase, β-1,4-glucanase, chitinase or protease inhibitory activities were detected.  相似文献