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81.
Kormanek Mariusz Małek Stanisław Banach Jacek Durło Grzegorz Jagiełło-Leńczuk Krystyna Dudek Katarzyna 《New Forests》2021,52(2):271-283
New Forests - Cultivation of seedlings in trays requires the use of specifically developed substrates. This study presents the results of the analyses of selected physical and mechanical parameters... 相似文献
82.
Using research and education to implement practical bed bug control programs in multifamily housing 下载免费PDF全文
Gary W Bennett Ameya D Gondhalekar Changlu Wang Grzegorz Buczkowski Timothy J Gibb 《Pest management science》2016,72(1):8-14
Multifamily housing facilities serving low‐income populations have been at the forefront of bed bug outbreaks. Research conducted in the past 8 years has consistently proven that integrated pest management (IPM) is the best approach for successful suppression of bed bug infestations. Bed bug IPM in multifamily settings is especially dependent upon a collaborative community or building‐wide effort involving residents, building staff and pest control technicians. Other components of a bed bug IPM program include regular monitoring to detect early‐stage bed bug infestations and combined use of non‐chemical and chemical interventions. Lastly, to reduce reinfestation rates and costs associated with bed bug control, it is critical to continue periodic monitoring and implement preventive control measures even after successful elimination of bed bugs has been achieved. © 2015 Society of Chemical Industry 相似文献
83.
Influence of temperature and Artemia enriched with ω‐3 PUFAs on the early ontogenesis of Atlantic sturgeon,Acipenser oxyrinchus Mitchill, 1815 下载免费PDF全文
Ryszard Kolman Oleksii Khudyi Olga Kushniryk Lidiia Khuda Maja Prusinska Grzegorz Wiszniewski 《Aquaculture Research》2018,49(5):1740-1751
Successful breeding of fish species in aquaculture depends on several factors, among which the temperature and feed are the most significant ones. This study was designed to evaluate the effect of temperature in the range of 14–18°C on the rate of embryogenesis and duration of larva period and to estimate the efficiency of Artemia nauplii enriched with PUFAs in growing sturgeon larvae. The temperature of 16°C is the most suitable for both egg incubation and Atlantic sturgeon prelarvae maintenance under aquaculture conditions. Even minor temperature fluctuations of 1 degree up or down leads to increased loss both of eggs and prelarvae. Increased temperature shortens the incubation period but has a lesser impact on the duration of prelarvae onset of external feeding. The technology of Artemia nauplii bioencapsulation with a PUFA‐containing supplement in A. oxyrinchus rearing increases sturgeon larvae weight by 1.5 times at a constant survival dynamic. 相似文献
84.
Zbigniew Adamiak Andrzej Sobolewski Grzegorz Walus Yauheni Zhalniarovich Joanna Glodek 《Topics in companion animal medicine》2018,33(3):63-64
This article presents a report of single-stage bilateral tibial tuberosity advancement for the treatment of cranial cruciate ligament rupture in an English bulldog. The reconstruction was performed by a new surgical technique involving tibial tuberosity advancement and fixation with two cranially placed lag screws. The patient was able to ambulate normally at a walk without lameness four days postoperatively. Except for bruising of the surgical site, no complications were observed during a six-month follow-up period. 相似文献
85.
Pavlo Bekhta Stanisław Proszyk Tomasz Krystofiak Miroslava Mamonova Grzegorz Pinkowski Barbara Lis 《Wood material science & engineering》2014,9(4):233-245
The effect of short-term thermomechanical densification of veneer on the surface roughness and surface anatomical changes in four wood species – alder (Alnus glutinosa Gaertn.), beech (Fagus sylvatica L.), birch (Betula verrucosa Ehrh.), and pine (Pinus sylvestris L.) – was studied. Veneer sheets were densified at a temperature of 100, 150, or 200°C and at a pressure of 4, 8, or 12 MPa for 4 minutes. Seven roughness parameters such as Ra, Rz, Rq, Rp, Rv, Rsk, and Rku were determined. Profile surface was recorded using a modified Carl Zeiss ME-10 profile gauging profilometer. Surface anatomical changes of veneer were examined using scanning electron microscopy. The results showed that densification temperature and pressure affect surface roughness of veneer. The surface became smoother, and roughness values decreased significantly (except for Rku which increased slightly) with increasing temperature and pressure of densification. The effect of temperature on surface roughness changes is more pronounced compared with that of densification pressure. The lowest values of surface roughness were recorded for pine veneer samples followed by alder, birch, and beech samples. These results can be used to provide initial data for adhesive application processes in woodworking industry. 相似文献
86.
Thomas Nehls Grzegorz Jozefaciuk Zofia Sokoowska Mieczyslaw Hajnos Gerd Wessolek 《植物养料与土壤学杂志》2006,169(1):16-24
The original light‐brown sandy seam filling of pavements in urban areas turns dark and changes its properties by the time due to various inputs of urban dust. Deposited Corg inputs do mostly not have natural characteristics but are man‐made, e.g., diesel dust. Thus, properties of the seam material are not predictable from experiences with forest or agricultural soils. Semiperviously sealed urban areas are sites of contaminant deposition as well as groundwater recharge. For an assessment of the resulting groundwater‐contamination risk in these areas, the properties of the seam material, which influences transport processes, must be known. The aim of this study was to investigate the pore‐system build‐up, which includes size distribution and fractal character in the seam material of urban sites. The investigated samples were taken from pavements adjacent to roads in Berlin and Warsaw. The micropore parameters (nanometer range) were characterized using water‐vapor desorption isotherms, mesopore parameters (micrometer range) were estimated from mercury‐intrusion porosimetry and macropore parameters (millimeter range) from water‐retention curves. Particle density, dry bulk density, and particle‐size distribution were measured using standard methods. Volumes of micro‐ and mesopores as well as particle densities and dry bulk densities correlated with Ctot contents. However, no such relation was found for macropore volumes. Compared to the original sandy seam filling, the altered seam material shows significantly higher Corg contents and higher amounts of micro‐ and mesopores. Therefore, the available water capacity increases by 0.05–0.11 m3 m–3, as compared to the original sandy seam filling. Compared to natural sandy soils having similar Corg contents, the seam material shows similar macropore volumes, but the volume of mesopores and micropores is a few times smaller. That is mainly because of the particulate character of the organic matter. 相似文献
87.
Mieczyslaw Hajnos Grzegorz Jozefaciuk Zofia Sokoowska Andreas Greiffenhagen Gerd Wessolek 《植物养料与土壤学杂志》2003,166(5):625-634
In this paper, we tried to find interrelations between water retention properties, surface characteristics, and structural features of sandy soils rich in organic matter. Raw humic, epihumic, and endohumic horizons of four acidic sandy forest soils were selected for this study. Specific areas and water adsorption energies were estimated from water vapor adsorption isotherms, micropore (nanometer range) parameters from desorption isotherms, mesopore (micrometer range) parameters from mercury intrusion porosimetry, and macropore (millimeter range) parameters from water retention curves measured using combined suction plate and pressure chamber methods. In the studied soils, pore volumes in all pore ranges were proportional to soil organic matter content. Thin column wicking technique was used to determine migration velocity vs. time dependence in the samples beds for a range of liquids of various surface tensions. From these dependencies the surface free energy and its components were estimated that were used for calculation of water contact angles and forces of interparticle interaction via a water meniscus. The dominant interactions in the studied soils were dispersive Lifshitz‐Van der Waals forces. In the two upper horizons polar acid‐base interactions were absent, however in the deepest horizons, high input of polar interactions occurred, due practically to electron‐donor component of the surface free energy. The electron‐acceptor contribution was low. The wettability of the soils was low in upper horizons as indicated by high water contact angles. 相似文献
88.
Chereau D Boczkowska M Skwarek-Maruszewska A Fujiwara I Hayes DB Rebowski G Lappalainen P Pollard TD Dominguez R 《Science (New York, N.Y.)》2008,320(5873):239-243
Initiation of actin polymerization in cells requires nucleation factors. Here we describe an actin-binding protein, leiomodin, that acted as a strong filament nucleator in muscle cells. Leiomodin shared two actin-binding sites with the filament pointed end-capping protein tropomodulin: a flexible N-terminal region and a leucine-rich repeat domain. Leiomodin also contained a C-terminal extension of 150 residues. The smallest fragment with strong nucleation activity included the leucine-rich repeat and C-terminal extension. The N-terminal region enhanced the nucleation activity threefold and recruited tropomyosin, which weakly stimulated nucleation and mediated localization of leiomodin to the middle of muscle sarcomeres. Knocking down leiomodin severely compromised sarcomere assembly in cultured muscle cells, which suggests a role for leiomodin in the nucleation of tropomyosin-decorated filaments in muscles. 相似文献
89.
Grzegorz Zięba Carl Smith Michael G. Fox Stan Yavno Eva Záhorská Mirosław Przybylski Gérard Masson Julien Cucherousset Hugo Verreycken Hein H. van Kleef Gordon H. Copp 《Ecology of Freshwater Fish》2018,27(3):874-883
Carotenoid‐based pigmentation is a striking feature of many taxa, yet the function, if any, of colour traits is often unclear. Pumpkinseed Lepomis gibbosus, a widely introduced freshwater sunfish that exhibits alternative male mating strategies, express a striking, red operculum spot. To investigate the potential function of this red spot as a signal in this species' mating system, we determined the presence and measured the size of red operculum spots in fish collected from 12 populations in five European countries in which pumpkinseed is an established non‐native species. We subsequently related the presence and size of the red spot to body size and mating strategy, based on an analysis of relative gonad size (gonado‐somatic index, GSI), using a mixed modelling approach. The study demonstrated that the presence of a red operculum spot in pumpkinseed is associated with sexual maturation, with GSI frequency distributions suggesting that cuckolders in some non‐native populations comprised both sneaker and satellite males, the latter not having previously been reported for this species. Further, the size of red spot correlated strongly with body size in parental and cuckolder males, although there was no difference in the presence or size of the red operculum spot between male mating strategies. The function of a red operculum spot in females is not clear but may be partly mediated by pleiotropic genetic mechanisms. Red operculum spots appear to function as signals of male maturation and body size in pumpkinseed, irrespective of mating strategy. 相似文献
90.
Transgenic cucumber lines expressing the chimeric pGT::Dhn24 gene do not show enhanced chilling tolerance in phytotron conditions 下载免费PDF全文