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11.
Sushko Sofia Ananyeva Nadezhda Ivashchenko Kristina Vasenev Vyacheslav Kudeyarov Valeriy 《Journal of Soils and Sediments》2019,19(8):3217-3225
Journal of Soils and Sediments - Urbanization significantly changes the carbon balance of the terrestrial ecosystem, an important component of which is soil CO2 emission. One of the main sources of... 相似文献
12.
James T Rothwell Thomas J Burnett Kristina Hacket Roderick Chevis L Barry Lowe 《Pest management science》2001,57(11):993-999
The depletion of zeta‐cypermethrin residues in bovine tissues and milk was studied. Beef cattle were treated three times at 3‐week intervals with 1 ml 10 kg?1 body weight of a 25 g litre?1 or 50 g litre?1 pour‐on formulation (2.5 and 5.0 mg zeta‐cypermethrin kg?1 body weight) or 100 mg kg?1 spray to simulate a likely worst‐case treatment regime. Friesian and Jersey dairy cows were treated once with 2.5 mg zeta‐cypermethrin kg?1 in a pour‐on formulation. Muscle, liver and kidney residue concentrations were generally less than the limit of detection (LOD = 0.01 mg kg?1). Residues in renal‐fat and back‐fat samples from animals treated with 2.5 mg kg?1 all exceeded the limit of quantitation (LOQ = 0.05 mg kg?1), peaking at 10 days after treatment. Only two of five kidney fat samples were above the LOQ after 34 days, but none of the back‐fat samples exceeded the LOQ at 28 days after treatment. Following spray treatments, fat residues were detectable in some animals but were below the LOQ at all sampling intervals. Zeta‐cypermethrin was quantifiable (LOQ = 0.01 mg kg?1) in only one whole‐milk sample from the Friesian cows (0.015 mg kg?1, 2 days after treatment). In whole milk from Jersey cows, the mean concentration of zeta‐cypermethrin peaked 1 day after treatment, at 0.015 mg kg?1, and the highest individual sample concentration was 0.025 mg kg?1 at 3 days after treatment. Residues in milk were not quantifiable beginning 4 days after treatment. The mean concentrations of zeta‐cypermethrin in milk fat from Friesian and Jersey cows peaked two days after treatment at 0.197 mg kg?1 and 0.377 mg kg?1, respectively, and the highest individual sample concentrations were 2 days after treatment at 0.47 mg kg?1 and 0.98 mg kg?1, respectively. © 2001 Society of Chemical Industry 相似文献
13.
Craig A. Kiebler Lyndsay Bottichio Latoya Simmons Colin Basler Rachel Klos Nikos Gurfield Elizabeth Roberts Akiko Kimura Linda S. Lewis Kiyomi Bird Felicia Stiles Linda K. Schlater Kristina Lantz Thomas Edling Casey Barton Behravesh 《Zoonoses and public health》2020,67(4):425-434
Reptiles are one of the fastest growing sectors in the United States pet industry. Reptile‐associated salmonellosis (RAS) continues to be an important public health problem, especially among children. We investigated an outbreak of human Salmonella infections resulting from serotypes Cotham and Kisarawe, predominately occurring among children. An outbreak of illnesses was identified in persons with exposure to pet bearded dragon lizards. Human and animal health officials, in cooperation with the pet industry, conducted epidemiologic, traceback and laboratory investigations. Onsite sampling was conducted at two US breeding facilities, one foreign breeding facility, and a large pet retail chain. A total of 166 patients in 36 states were identified with illness onset dates from 02/2012–06/2014. The median patient age was 3 years (range, <1–79 years), 57% were aged ≤5 years, and 37% were aged ≤1 year. Forty‐four patients (37%) were hospitalized, predominantly children. Sampling at breeding facilities and a national pet store chain resulted in isolation of outbreak serotypes at each facility; isolation proportions ranged from 2%–24% of samples collected at each facility.Epidemiologic, microbiologic and traceback evidence linked an outbreak of uncommon Salmonella serotypes to contact with pet bearded dragons. The high proportion of infants involved in this outbreak highlights the need to educate owners about the risk of RAS in children and the potential for household contamination by pet reptiles or their habitats. Strategies should be developed to improve breeding practices, biosecurity and monitoring protocols to reduce Salmonella in the pet reptile trade. 相似文献
14.
Sara Ringmark Arne Lindholm Ulf Hedenstr?m Michael Lindinger Kristina Dahlborn Clarence Kvart Anna Jansson 《Acta veterinaria Scandinavica》2015,57(1)
Background
Training of Standardbred race horses aims to improve cardiovascular and metabolic functions but studies on the effects of different training strategies from breaking till racing are lacking. Sixteen horses with the goal to race as 3-year-olds were studied from breaking (1-year-olds) to December as 3-year-olds. Horses were allocated to either a control (C) or reduced (R) training program from 2 years of age. The aim was to evaluate the effect of reducing the distance of high intensity exercise by 30% with respect to velocity at lactate concentration 4 mmol/l (VLa4), blood lactate and cardiovascular response. All training sessions were documented and heart rate (HR) was recorded. A standardized exercise test of 1,600 m was performed 10 times and a VLa4 test was performed five times.Results
C horses initially exercised for a longer time with a HR >180 beats per minute compared to R horses (P < 0.05) but after 6–9 months, time with HR >180 bpm decreased in C and were similar in the two groups (P > 0.05). Over the 2-year period, recovery HR after the 1,600 m-test decreased in both groups but was within 2 months lower in C than in R (P < 0.05). C horses also had lower resting HR as 3-year-olds (P < 0.01) than R horses. In C, post exercise hematocrit was higher than in R (P < 0.05). There was a tendency (P < 0.1) towards a larger aortic diameter in C as 3-year-olds (C: 1.75 ± 0.05, R: 1.70 ± 0.05 cm/100 kg BW). Left ventricle diameter and blood volume (in December as 2-year-olds) did not differ between groups. There were no differences between groups in post exercise blood lactate concentration or in VLa4. Both groups were equally successful in reaching the goal of participation in races.Conclusions
Horses subjected to a reduced distance of high intensity training from the age of 2 showed an attenuated heart rate response, but were able to maintain the same VLa4 and race participation as horses subjected to longer training distances. 相似文献15.
Kristina G. Miles DVM MS Jimmy C. Lattimer DVM MS Gary F. Krause PhD David W. Knapp DVM Candace E. Sayles DVM 《Veterinary radiology & ultrasound》1988,29(6):258-263
Sonographic evaluation of the pancreas was performed in ten healthy research dogs following intraperitoneal fluid administration. Physiological saline solution was aseptically introduced into the peritoneal cavity of each dog to create an acoustic window that would facilitate sonographic delineation of normal pancreatic tissues. Abdominal ultrasound examinations were performed in all dogs before and after the production of the diagnostic hydroperitoneum. Sonograms of the pancreas and other abdominal organs were scored on the basis of image clarity by experienced and novice ultrasonographers. Statistical analysis was then used to compare the effectiveness of each preparation method. A significant difference (P < 0.05) was established between the scores from the diagnostic hydroperitoneum sonograms and the baseline scans performed without intraperitoneal fluid placement. Sonographic visualization scores for the pancreas and other abdominal organs were increased following production of the diagnostic hydroperitoneum. These results indicate that the technique of diagnostic hydroperitoneum will significantly improve ultrasonographic visualization of the pancreas, and may prove useful in the diagnosis of canine pancreatic disease. 相似文献
16.
First morphological characterization of 'Candidatus Mycoplasma turicensis' using electron microscopy
Willi B Museux K Novacco M Schraner EM Wild P Groebel K Ziegler U Wolf-Jäckel GA Kessler Y Geret C Tasker S Lutz H Hofmann-Lehmann R 《Veterinary microbiology》2011,149(3-4):367-373
At least three haemotropic mycoplasmas have been recognized in cats: Mycoplasma haemofelis (Mhf), 'Candidatus Mycoplasma haemominutum' (CMhm) and 'Candidatus M. turicensis' (CMt). The latter was originally identified in a Swiss pet cat with haemolytic anaemia and shown to be prevalent in domestic cats and wild felids worldwide using molecular methods. So far, there has been no confirmatory morphological evidence of the existence of CMt presumably due to low blood loads during infection while CMhm has only been characterized by light microscopy with discrepant results. This study aimed to provide for the first time electron microscopic characteristics of CMt and CMhm and to compare them to Mhf. Blood samples from cats experimentally infected with CMt, CMhm and Mhf were used to determine copy numbers in blood by real-time PCR and for transmission and scanning electron microscopy. High resolution scanning electron microscopy revealed CMt and CMhm to be discoid-shaped organisms of 0.3 μm in diameter attached to red blood cells (RBCs). In transmission electron microscopy of CMt, an oval organism of about 0.25 μm with several intracellular electron dense structures was identified close to the surface of a RBC. CMhm and CMt exhibited similar morphology to Mhf but had a smaller diameter. This is the first study to provide morphological evidence of CMt thereby confirming its status as a distinct haemoplasma species, and to present electron microscopic features of CMhm. 相似文献
17.
Falush D Wirth T Linz B Pritchard JK Stephens M Kidd M Blaser MJ Graham DY Vacher S Perez-Perez GI Yamaoka Y Mégraud F Otto K Reichard U Katzowitsch E Wang X Achtman M Suerbaum S 《Science (New York, N.Y.)》2003,299(5612):1582-1585
Helicobacter pylori, a chronic gastric pathogen of human beings, can be divided into seven populations and subpopulations with distinct geographical distributions. These modern populations derive their gene pools from ancestral populations that arose in Africa, Central Asia, and East Asia. Subsequent spread can be attributed to human migratory fluxes such as the prehistoric colonization of Polynesia and the Americas, the neolithic introduction of farming to Europe, the Bantu expansion within Africa, and the slave trade. 相似文献
18.
AbstractA field experiment was conducted during two consecutive growing seasons (2013 and 2014) to evaluate the effects of inoculations with Rhizobium and Azotobacter on the growth and yield of two chickpea (Cicer arietinum L.) varieties under saline (5.8 dS m?1) arid condition. The single treatment of either Rhizobium or Azotobacter exhibited to promote the growth of chickpea to some level, however, co-inoculation produced more effects and increased the shoot dry weight (30.3 and 26.4%), root dry weight (17.5 and 26.3%), nodule number (79.1 and 43.8 piece per plant), nitrogen content in roots (9.62 and 10.9%), in shoots (12.6 and 8.3%) and seed protein (7.1 and 4.3%) in both Flip06-102 and Uzbekistan-32 chickpea varieties compared to the control. Our studies showed that the highest yield response of 429 (27.9%) and 538 (23.9%) kg?ha?1 over the control was revealed by the co-inoculation with Rhizobium and Azotobacter inoculants in Flip 06-102 and Uzbekistan-32, respectively. A new introduced Flip 06-102 chickpea variety was more salt tolerant and had higher root nodulation than the local Uzbekistan-32 chickpea variety. Nitrogen (N), phosphorus (P), and potassium (K) contents in the shoots and roots were significantly (p?0.05) higher in the co-inoculated treatment, while plant sodium (Na+) concentration was the lowest for both chickpea varieties exhibiting co-inoculation alleviated the detrimental effects of salinity. Therefore, the co-inoculation of Rhizobium plus Azotobacter could be applied to improve the vegetative growth and yield of chickpea and to alleviate the effects of salt stress. 相似文献
19.
Jaramillo TF Jørgensen KP Bonde J Nielsen JH Horch S Chorkendorff I 《Science (New York, N.Y.)》2007,317(5834):100-102
The identification of the active sites in heterogeneous catalysis requires a combination of surface sensitive methods and reactivity studies. We determined the active site for hydrogen evolution, a reaction catalyzed by precious metals, on nanoparticulate molybdenum disulfide (MoS2) by atomically resolving the surface of this catalyst before measuring electrochemical activity in solution. By preparing MoS2 nanoparticles of different sizes, we systematically varied the distribution of surface sites on MoS2 nanoparticles on Au(111), which we quantified with scanning tunneling microscopy. Electrocatalytic activity measurements for hydrogen evolution correlate linearly with the number of edge sites on the MoS2 catalyst. 相似文献
20.