Evaluation of nitrogen cycling and fish production in seasonal ponds (‘Fingerponds’) in Lake Victoria wetlands,East Africa using a dynamic simulation model     

Rose C Kaggwa  Anne A Van Dam  Julius Kipkemboi  Patrick Denny 《Aquaculture Research》2010,42(1):74-90

A dynamic model was developed to simulate nitrogen (N) flows and fish production in seasonal wetland fish ponds (Fingerponds) based on organic manuring and natural food production. The model incorporates pond water depth, food availability, fish stocking densities, fish and fingerling weights at stocking, reproduction rate, manure type and application rates. The ponds were fertilized fortnightly with 1042 kg ha⁻¹ chicken manure. The model captured the dynamics of hydrology, nutrients and fish and demonstrated that similar fundamental processes underlie fish production in these systems. The model predicted annual fish yields of up to 2800 kg ha⁻¹. Simulated fish production, chlorophyll a and dissolved inorganic N concentrations were comparable with field measurements. Using the model, N budgets and estimates of all N flows were made. Most of the N input into the ponds (60–70%) accumulated in the bottom detritus of the pond and only 8–10% was converted into fish biomass, of which about half consisted of small fish. Fish production in Fingerponds was limited by turbidity induced light limitation and by nutrient limitation. Reduction of variability of fish production should come from reduced turbidity and sufficient nutrient input to minimize light limitation and maximize fish growth.  相似文献   

Novel adult feeding disruption test (FDT) to detect insecticide resistance of lepidopteran pests in cotton     

B van Kretschmar  Ana R Cabrera  Julius R Bradley  R Michael Roe 《Pest management science》2013,69(5):652-660

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水稻穗腐病病菌致病性、发生规律及防控技术研究   总被引：3，自引：0，他引：3  

侯恩庆  张佩胜  王玲  刘恩勇  刘连盟  黄世文   《植物保护》2013,39(1):121-127

穗腐病是近年发生危害严重的水稻穗部病害.本研究对穗腐病的发生、流行原因进行了分析,分离了病原菌并测定了致病性,筛选了防治该病的杀菌剂并进行了田间防效试验.结果表明,紧穗型的粳稻及籼/粳杂交稻组合较穗型松散的籼稻及其杂交组合更易感病.水稻孕穗后期-抽穗扬花期遇阴雨高湿、温暖天气该病发生危害重.用分离到的4个菌(层出镰刀菌、澳大利亚平脐蠕孢菌、新月弯孢菌和细交链孢菌)进行人工接种,均能使稻粒感病,初步确定层出镰刀菌为主要初侵染菌.室内抑菌测试结果显示,5 mg/L以上浓度的多菌灵、咪鲜胺和苯醚甲环唑·丙环唑(爱苗)对层出镰刀菌生长的抑制效果达到81.31％～100％.抑制中浓度为0.000 7～0.947 6 mg/L.田间试验结果表明,在水稻孕穗后期和抽穗扬花期用三唑酮、多菌灵或甲基硫菌灵喷雾防治一次,防效在70％左右.  相似文献   

Acetylcholinesterase Inhibitory Activity of Pigment Echinochrome A from Sea Urchin Scaphechinus mirabilis     

Sung Ryul Lee  Julius Ryan D. Pronto  Bolor-Erdene Sarankhuu  Kyung Soo Ko  Byoung Doo Rhee  Nari Kim  Natalia P. Mishchenko  Sergey A. Fedoreyev  Valentin A. Stonik  Jin Han 《Marine drugs》2014,12(6):3560-3573

Echinochrome A (EchA) is a dark-red pigment of the polyhydroxynaphthoquinone class isolated from sea urchin Scaphechinus mirabilis. Acetylcholinesterase (AChE) inhibitors are used in the treatment of various neuromuscular disorders, and are considered as strong therapeutic agents for the treatment of Alzheimer’s disease (AD). Although EchA is clinically used to treat ophthalmic diseases and limit infarct formation during ischemia/reperfusion injury, anti-AChE effect of EchA is still unknown. In this study, we investigated the anti-AChE effect of EchA in vitro. EchA and its exhausted form which lost anti-oxidant capacity did not show any significant cytotoxicy on the H9c2 and A7r5 cells. EchA inhibited AChE with an irreversible and uncompetitive mode. In addition, EchA showed reactive oxygen species scavenging activity, particularly with nitric oxide. These findings indicate new therapeutic potential for EchA in treating reduced acetylcholine-related diseases including AD and provide an insight into developing new AChE inhibitors.  相似文献   

Spatial predictors of bovine tuberculosis infection and Brucella spp. exposure in pastoralist and agropastoralist livestock herds in the Ruaha ecosystem of Tanzania     

Annette Roug  Deana Clifford  Jonna Mazet  Rudovick Kazwala  Julius John  Peter Coppolillo  Woutrina Smith 《Tropical animal health and production》2014,46(5):837-843

While many studies investigate animal-related risk factors for disease, few have considered environmental or spatial risk factors in the dynamics of bovine tuberculosis (bTB) and brucellosis. In the Ruaha ecosystem of Tanzania, we investigated the role of household location as a predictor for infection with Mycobacterium bovis and exposure to Brucella in pastoralist and agropastoralist cattle herds in a typical African wildlife-livestock-human interface. ArcGIS was utilized to calculate Euclidian distances between households and the nearest river, village center, protected area, and other infected households, followed by multivariate logistic regression to assess the association between risk factors and herd-level bTB and Brucella outcomes. Global and local spatial clustering of bTB-infected and Brucella-exposed herds was explored using the Cuzick-Edward’s test and SaTScan spatial scan statistics. Households located farther from rivers and closer to village centers and herds belonging to agropastoralists were more likely to have bTB-positive cattle. Risk of Brucella exposure increased with proximity to protected areas. One spatial cluster of households with Brucella spp. seropositive cattle was identified. Spatial factors may be useful for assessing disease risk and for formulating intervention and control strategies for households that manage cattle in ecosystems characterized by seasonally limited resources and intense wildlife-livestock interfaces.  相似文献   

Acknowledgements to referees     

Asko Mäki‐Tanila  Rodolfo Cantet  Ignacy Misztal  Miguel Pérez‐Enciso  Henner Simianer  Julius van der Werf 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2014,131(6):536-536

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Primary renal neoplasia of dogs     

Bryan JN  Henry CJ  Turnquist SE  Tyler JW  Liptak JM  Rizzo SA  Sfiligoi G  Steinberg SJ  Smith AN  Jackson T 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2006,20(5):1155-1160

BACKGROUND: Primary renal tumors are diagnosed uncommonly in dogs. HYPOTHESIS: Signs and survival will differ among different categories of primary renal tumors. ANIMALS: Data were collected from the medical records of 82 dogs with primary renal tumors diagnosed by examination of tissue obtained by ultrasound-guided biopsy, needle aspiration, surgery, or at postmortem examination. METHODS: This was a multi-institutional, retrospective study. RESULTS: Forty-nine dogs had carcinomas, 28 had sarcomas, and 5 had nephroblastomas. The dogs were geriatric (mean 8.1 years; range: 1-17) with a weight of 24.9 kg (range: 4.5-80). Tumors occurred with equal frequency in each kidney with 4% occurring bilaterally. Initial signs included one or more of hematuria, inappetance, lethargy. weight loss, or a palpable abdominal mass. Pain was reported more frequently in dogs with sarcomas (5/28). The most common hematologic abnormalities were neutrophilia (22/63), anemia (21/64), and thrombocytopenia (6/68). Polycythemia was present in 3 dogs and resolved with treatment. Hematuria (28/49), pyuria (26/49), proteinuria (24/50), and isosthenuria (20/56) were the most frequently observed abnormalities on urinalysis. Pulmonary metastases were noted on thoracic radiographs in 16% of dogs at diagnosis. Seventy-seven percent of dogs had metastatic disease at the time of death. Median survival for dogs with carcinomas was 16 months (range 0-59 months), for dogs with sarcomas 9 months (range 0-70 months), and for dogs with nephroblastomas 6 months (range 0-6 months). CONCLUSIONS AND CLINICAL IMPORTANCE: Primary renal tumors in dogs are generally highly malignant with surgery being the only treatment that improves survival.  相似文献   

Peat leachmound treatment of residential wastewater in sub-Arctic Alaska     

Raymond Z. Riznyk  Julius Rockwell Jr.  Leroy C. Reid Jr.  Sabra L. Reid 《Water, air, and soil pollution》1993,69(1-2):165-177

In many areas of the North, conventional septic systems cannot be installed or have failed because of inadequate drainage. Conventional domestic, on-site wastewater may contaminate shallow water tables and surface waters. The effectiveness of two pilot peat leachfields in treating septic wastewater was investigated for approximately two years by comparing the quality of the untreated wastewater collected from the septic system lift stations to the quality of the peat leachate. The quality of the leachate, based on parameters such as BOD, COD, TSS, NO₃-N, TKN, total-P, pH, fecal and total coliform bacteria, color, turbidity, and DO, is similar to wastewater that has undergone tertiary treatment. Temperatures below the leachmound distribution pipes ranged between 1° and 6 °C. Clogging of the interstices with an organic slime was not encountered. The results of the study show that peat leachmounds can be adopted to treat residential wastewater in rural sub-Arctic Alaska and other northern tier countries without compromising ground or surface water quality.  相似文献   

Outcomes associated with vaginectomy and vulvovaginectomy in 21 dogs     

Jessica A. Ogden DVM  DACVS-SA  Laura E. Selmic BVetMed  MPH  DACVS-SA  Julius M. Liptak BVSc  MVetClinStud  FACVSc  DACVS-SA  DECVS  Michelle L. Oblak DVM  DVSc  DACVS-SA  William T. N. Culp VMD  DACVS  Carlos H. de Mello Souza DVM  MS  DACVIM  DACVS  Janet A. Grimes DVM  MS  DACVS-SA  Marine Traverson DVM  MS  DACVS-SA  Megan Cray VMD  Brittany E. Abrams DVM  Vincent A. Wavreille DVM  MS  MRCVS  DACVS-SA 《Veterinary surgery : VS》2020,49(6):1132-1143

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Clinical findings and outcomes of 153 dogs surgically treated for intestinal intussusceptions     

Philippe Chagnon Larose DVM  Ameet Singh DVM  DVSc  DACVS-SA  Michelle A. Giuffrida VMD  MSCE  DACVS  Galina Hayes PhD  DACVECC  DACVS  James Franklin Moyer BSc  Janet A. Grimes DVM  MS  DACVS-SA  Jeffrey Runge DVM  DACVS  Chiara Curcillo DVM  Christopher B. Thomson DVM  Philipp D. Mayhew BVM&S  DACVS-SA  Ross Bernstein DVM  Christopher Dominic DVM  Kelley Thieman Mankin DVM  DACVS-SA  Penny Regier DVM  MS  DACVS-SA  J. Brad Case DVM  MS  DACVS-SA  Shiori Arai DVM  PhD  DACVS-SA  Mathieu Gatineau DMV  IPSAV  MSc  DACVS  DECVS  DACVSMR  Julius M. Liptak BVSC  MVetClinStud  FACVSc  DACVS-SA  DECVS  ACVS  Charles Bruce DVM  DVSc  DACVS 《Veterinary surgery : VS》2020,49(5):870-878

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