Perspectives on validation in digital soil mapping of continuous attributes—A review     

Kristin Piikki  Johanna Wetterlind  Mats Sderstrm  Bo Stenberg 《Soil Use and Management》2021,37(1):7-21

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Effect of seminal plasma concentration and various extenders on postthaw motility and glass wool-Sephadex filtration of cryopreserved stallion semen     

Alghamdi AS  Troedsson MH  Xue JL  Crabo BG 《American journal of veterinary research》2002,63(6):880-885

OBJECTIVE: To compare the effect of semen extender and seminal plasma on postthaw motility and filtration through a glass wool-Sephadex (GWS) filter for frozen stallion semen. SAMPLE POPULATION: 7 stallions from which we collected > or = 3 ejaculates/stallion. PROCEDURES: 4 experiments were conducted to evaluate postthaw quality of frozen stallion semen. Kenney extender was compared with glucose-EDTA extender by use of various dilution rates that resulted in differing concentrations of seminal plasma. Stallions known to produce semen with poor postthaw quality were used to investigate whether a particular extender or dilution rate could improve ability of such semen to survive freeze-thaw procedures. RESULTS: Use of Kenney extender as the centrifugation extender significantly improved postthaw motility and GWS filtration, compared with glucose-EDTA. Extending semen at a dilution of 1:3 was significantly better than 1:1 for both motility and GWS filtration. In addition, including seminal plasma at a concentration of 5% in the cryopreserved semen resulted in significantly higher yield of spermatozoa after GWS filtration, compared with complete removal of SP or use of seminal plasma at 25%. Lastly, semen with poor postthaw quality had significantly improved postthaw quality in regard to motility and GWS filtration when semen was frozen with seminal plasma at a concentration of 5%, compared with semen frozen with seminal plasma at a concentration of 25%. CONCLUSIONS AND CLINICAL RELEVANCE: Use of Kenney extender at a high dilution (> or = 1:3) immediately after collection of semen can improve postthaw quality of frozen stallion semen.  相似文献   

Low Mw-lignin fractions together with vegetable oils as available oligomers for novel paper-coating applications as hydrophobic barrier     

Stefan Antonsson  Gunnar Henriksson  Mats Johansson  Mikael E. Lindström 《Industrial Crops and Products》2008,27(1):98-103

Lignin residues are available in large amounts as kraft lignin from chemical pulping processes. This lignin is mainly incinerated in recovery boilers. The recovery boilers are often the bottle-necks in the overall pulping process when pulp production increases are desired. Through cross-flow nano-filtration of the black liquor from kraft pulping, a low-molecular weight lignin fraction can be removed thus decreasing the organic load on the recovery boilers. The low-molecular weight lignin fraction furthermore exhibit different characteristics compared to other commercial kraft lignins and represents a new raw material source in novel applications.The low-molecular weight lignin was used together with a vegetable oil to produce a new hydrophobic lignin derivative similar to suberin. The lignin and the lignin derivative was analysed with FT-IR, UV–vis and SEC. The ability of the product to make paper surfaces hydrophobic was also evaluated.The results demonstrate the possibility to make a suberin-like lignin derivative that is potentially of interest in paper-coating applications due to its capability to interact well with wood fibres and make paper hydrophobic.  相似文献   

Presence of Bacteria on the External Genitalia of Healthy Stallions and its Transmission to the Mare at the Time of Breeding by Live Cover     

Katheryn L. Cerny  Tom V. Little  Charles F. Scoggin  Robert J. Coleman  Mats H.T. Troedsson  Edward L. Squires 《Journal of Equine Veterinary Science》2014

The current field study used thoroughbred stallions and mares from central Kentucky to investigate the occurrence of potentially pathogenic bacteria on the stallion's external genitalia, based on cultures, and investigated the occurrence of bacteria and type of isolate in the mare's uterus after breeding by live cover to stallions with or without positive bacterial cultures. Fifteen thoroughbred stallions and 206 mares from two central Kentucky thoroughbred farms were used during the 2010 and 2011 breeding seasons. Samples for bacteriological evaluation were taken from the prepuce and postejaculate urethra (n = 201) of stallions. Uterine swabs (n = 264) were collected 12-18 hours postbreeding. For statistical analyses, a chi-squared test was used to test the relationship between stallion culture results and postbreeding uterine culture results, as well as the effect of bacterial types found on the stallion cultures with bacterial types found on the postbreeding uterine cultures. Of stallion cultures, 22.4% were positive for potentially pathogenic bacteria, with Streptococcus equi subspecies zooepidemicus (51.1%) being the most common isolate. Uterine cultures resulted in a 29.2% positive rate for potentially pathogenic bacteria, with S. equi subsp. zooepidemicus (90.9%) being the most common. There was no difference (P > .05) in the occurrence of bacteria or type of isolate found on uterine cultures after breeding stallions with or without positive cultures. In conclusion, potentially pathogenic bacteria found on the stallion's external genitalia did not affect the occurrence and type of bacterial isolate found in the mare's uterus after breeding by live cover.  相似文献   

Virulence studies of Swedish net blotch isolates (Drechslera teres) and identification of resistant barley lines     

Rickard Jonsson  Tomas Bryngelsson  Mats Gustafsson 《Euphytica》1997,94(2):209-218

Six Swedish and one Canadian single spore isolate of Drechslera teres f. teres were used to screen 109 barley lines for disease resistance and to select a differential set of barley lines for use in assessing pathogen virulence. A large variation for net blotch resistance was found among the 109 barley lines which were classified into four groups, those showing: 1) only resistant reactions; 2) differential reactions; 3) only intermediate reactions and 4) only susceptible reactions. The European commercial varieties included, showed susceptibility to all Swedish isolates, but a few were resistant to the Canadian isolate. The 18- member differential set separated 25 Swedish and two Canadian isolates of D. teres into 14 pathotypes, three of which made up 59% of the isolates. Only one barley differential (CI 9776) was resistant to all net form isolates. Host selection on the pathogen seems to be present as all six isolates obtained from cv. Golf belonged to the same pathotype and 4 of 5 isolates from cv. Karin shared the same virulence pattern. The net form of net blotch (D. teres f. teres) predominated in the sampled regions and only one of 26 Swedish isolates was of the spot form (D. teres f. maculata). This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Monitoring of heavy metals in protected forest catchments in Sweden     

Mats Aastrup  Åke Iverfeldt  Lage Bringmark  Hans Kvarnäs  Bo Thunholm  Hans Hultberg 《Water, air, and soil pollution》1995,85(2):755-760

Long-term integrated catchment monitoring within the Swedish Environmental Monitoring Programme (PMK) aims primarely at the fate and effects of pollutants in mature ecosystems, mainly protected boreal forests. The measurements that were conducted since the early eighties, with some variation, included deposition, throughfall, litterfall and the chemistry of soil water, groundwater and runoff water.Together with, or perhaps partly due to acidification, accumulation and transport of heavy metals are a serious threat to the ecosystem and in the end to the health of human beings. This paper discuss the behaviour of Hg, Pb, Cd, Zn and Cu based on the experiece gained from the studies in the small catchment areas. The importance of present deposition, soil storage and biogeochemical condition for metal mobility to the transport of metals is discussed The storages of Hg and Pb have been built up during a long time span and are very large in comparison with the flux. The present atmospheric deposition have probably little impact on the flux, which rather is governed by the biogeochemical conditions. There is still a small accumulation of Cd, but its great mobility under acidic conditions makes input and output almost in balance. A reduction in deposition will probably have an immediate effect on flux, which also is the case for Zn. Cu generally accumulates in soil. The mobility and hence the flux are certainly regulated by the biogeochemical conditions, but more detailed studies are required to reveal the general mecanisms for Cu transport within the catchment.  相似文献   

Impacts from Deposition on Swedish Forest Ecosystems Identified by Integrated Monitoring     

Lars Lundin  Mats Aastrup  Lage Bringmark  Sven Bråkenhielm  Hans Hultberg  Kjell Johansson  Karin Kindbom  Hans Kvarnäs  Stefan Löfgren 《Water, air, and soil pollution》2001,130(1-4):1031-1036

Integrated monitoring of ecosystems (IM) is an international co-operative programme (ICP) to control effects of air pollution and climate change on water, soil and biological systems. It is a part of the Convention on Long-Range Transboundary Air Pollution (CLRTAP) of the United Nations Economic Commission of Europe (UN/ECE). The ICP-IM is undertaken on sites/catchments to investigate acidification, eutrophication and heavy metals with an integrated approach. In Sweden, long-term time series from forest ecosystems, with a long and stable continuity, will reveal trends and changes in processes and enable modelling to be undertaken. Investigations of acidity/alkalinity in relation to mineral and organic acids indicated the importance of atmospheric deposition. Recent results show very high inorganic nitrogen retention (99%), a net loss of sulphur originating mainly from organic horizons, and a high inorganic aluminium content in the illuvial soil horizons which could be detrimental to forests. Forest deficiency could also be caused by an observed ongoing translocation of Zn to deeper soil layers implying a movement towards increased release to surface waters.  相似文献   

Imaging bond formation between a gold atom and pentacene on an insulating surface     

Repp J  Meyer G  Paavilainen S  Olsson FE  Persson M 《Science (New York, N.Y.)》2006,312(5777):1196-1199

A covalent bond between an individual pentacene molecule and a gold atom was formed by means of single-molecule chemistry inside a scanning tunneling microscope junction. The bond formation is reversible, and different structural isomers can be produced. The single-molecule synthesis was done on ultrathin insulating films that electronically isolated the reactants and products from their environment. Direct imaging of the orbital hybridization upon bond formation provides insight into the energetic shifts and occupation of the molecular resonances.  相似文献   

Long-term dynamics of leaf and root decomposition and nitrogen release in a grey alder (Alnus incana (L.) Moench) and silver birch (Betula pendula Roth.) stands     

Gunnar Morozov  Jürgen Aosaar  Mats Varik  Hardo Becker  Krista Lõhmus  Allar Padari 《Scandinavian Journal of Forest Research》2019,34(1):12-25

The decomposition of the leaf litter, fine roots (d?<?2?mm) and coarser roots (2?≤?d?<?5?mm) of grey alder and silver birch, as well as of α-cellulose sheets using the litterbag method was studied in two experimental stands on Podzoluvisol soils in Southern Estonia. For both tree species, the coarser roots decomposed faster than the fine roots, (p?<?.05), tree species did not affect the decomposition rate of the roots (p?>?.5). The nitrogen (N) input to soil from aboveground litter was multiple times higher than the N flux from roots. The remaining relative ash-free mass of the leaves of grey alder and silver birch after three and a half years was similar. After 11 years the remaining relative ash-free mass of the fine and coarser roots of grey alder still accounted for around 10% of the initial value. For silver birch the remaining value was around 20% after 9 years. The litterbag method to underestimates in fertile soils the decomposition of organic matter and thus did not reflect the actual dynamics of decomposition.  相似文献   

Adaptation of regional digital soil mapping for precision agriculture     

Mats Söderström  Gustav Sohlenius  Lars Rodhe  Kristin Piikki 《Precision Agriculture》2016,17(5):588-607

In the initial phase of a national project to map clay, sand and soil organic matter (SOM) content in arable topsoil in Sweden, a study area in south-west Sweden comprising about 100 000 ha of arable land was assessed. Models were created for texture, SOM and two estimated variables for lime requirement determination (target pH and buffering capacity), using a data mining method (multivariate adaptive regression splines). Two existing reference soil datasets were used: a grid dataset and a dataset created for individual farms. The predictor data were of three types: airborne gamma-ray spectrometry data, digital elevation from airborne laser scanning, and legacy data on Quaternary geology. Validations were designed to suit applicability assessments of prediction maps for precision agriculture. The predictor data proved applicable for regional mapping of topsoil texture at 50 × 50 m² spatial resolution (root mean square error: clay = 6.5 %; sand = 13.2 %). A novel modelling strategy, ‘Farm Interactive’, in which soil analysis data for individual farms were added to the regional data, and given extra weight, improved the map locally. SOM models were less satisfactory. Variable-rate application files for liming created from derived digital soil maps and locally interpolated soil data were compared with ‘ground truth’ maps created by proximal sensors on one test farm. The Farm Interactive methodology generated the best predictions and was deemed suitable for adaptation of regional digital soil maps for precision agricultural purposes.  相似文献