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1.
Rivka Manor Ran Segev Marcia Pimenta Leibovitz Eliahu D. Aflalo Amir Sagi 《Aquacultural Engineering》2002,26(4):263-276
In the process of exploring ways to intensify crayfish culture, a growout system of individual cages (cells) was designed to determine the effects of gender and cell size on the growth of the red claw crayfish Cherax quadricarinatus. Cells of three different diameters—large (25 cm), medium (20 cm) and small (16 cm)—were used. When crayfish were stocked at a mean weight of approximately 10 g, growth rate of males was significantly higher than that of females. The growth rate of the males in the large cells was 0.31±0.14 g/day, while that of the females was 0.18±0.09 g/day. The size of the cell had significant influence on the weight of males. Male crayfish in the large and medium cells grew better than those in the small cells. When males were stocked at a higher mean weight (about 23 g), their mean weight after 206 days was higher in the large cells (69.28±15.72 g) than in the small cells (58.11±12.66 g), suggesting that the growth of large males was also affected by cell size. Regardless of cell size, male animals of this species grew faster than females under conditions of individual cells. This intensive culture method appears to present a powerful improvement in yields, by as much as two orders of magnitude, in comparison with communal cultures. 相似文献
2.
Salas JH González MM Noa M Pérez NA Díaz G Gutiérrez R Zazueta H Osuna I 《Journal of agricultural and food chemistry》2003,51(15):4468-4471
A study was conducted to measure residues of 13 organophosphorus (OP) pesticides, widely used as dairy cattle ectoparasiticides or in crops used for animal feed, in homogenized and pasteurized Mexican milk samples. Four different milk brands with high distribution were collected biweekly during a 12 month period (n = 96) in supermarkets. OP pesticide residues were measured by gas chromatography with a flame photometric detector. Approximately 39.6% of the samples contained detectable levels of OP pesticide residues. Eight samples contained residues exceeding established maximum residue limits (MRL), and the OP pesticides present in these samples were dichlorvos (five samples), phorate, chlorpyrifos, and chlorfenvinphos (one sample, respectively). Average residues of 13 OP pesticides measured were below established MRLs ranging between 0.0051 and 0.0203 ppm. 相似文献
3.
Laura Chalupowicz Michal Reuven Orit Dror Noa Sela Saul Burdman Shulamit Manulis-Sasson 《Plant pathology》2020,69(9):1787-1797
Acidovorax citrulli is the causal agent of bacterial fruit blotch disease of cucurbits. Strains of this pathogen are distributed into two major groups: Group I strains have been mainly isolated from melon and other non-watermelon cucurbits, while Group II strains have been mainly recovered from watermelon. Here we report the characterization of strains T1 and EP isolated from diseased tomato and eggplant plants, respectively, and further confirmed to belong to A. citrulli species. Based on PCR, PFGE, and rep-PCR, these strains showed high similarity to the Group II strain 7a1. Sequencing and comparative analyses revealed that the genomes of T1 and EP aligned with that of the Group II model strain AAC00-1, over 97.88% and 99.22%, respectively. The virulence of T1, EP, and 7a1 determined on tomato, eggplant, and watermelon was similar and significantly higher than that of Group I strain M6. In contrast, M6 was more virulent on melon. Expression levels of seven virulence genes measured 24 hr after inoculation of tomato, eggplant, watermelon, and melon showed that the expression pattern was generally similar in strains 7a1, T1, and EP, whereas for M6 the expression was high only on melon. Overall, our results indicate that the solanaceous strains belong to Group II. To the best of our knowledge, this is the first study that reports characterization of A. citrulli strains isolated from solanaceous species. The fact that A. citrulli is able to naturally colonize and cause disease in non-cucurbit crops poses additional challenges for management of this important pathogen. 相似文献
4.
To assess whether and how environmental values and sense of place relate to sustainable farming practices, we conducted a study in South Kona, Hawaii, addressing environmental values, sense of place, and farm sustainability in five categories: environmental health, community engagement and food security, culture and history, education and research, and economics. We found that the sense of place and environmental values indexes showed significant correlation to each category of sustainability in both independent linear regressions and multivariate regression. In total, sense of place explained a larger share of the overall farm performance. However, each indicator showed relative strengths; environmental values showed significantly higher correlation to environmental and educational practices. Furthermore the scales were complimentary, and the use of both scales greatly improved prediction of good farming practices from a multiple-impact perspective. With implications for community and environmental impacts, results suggest that a more comprehensive view of farmers’ environmental values and place connections may help illuminate individual farmers’ decisions and sustainability-related practices. 相似文献
5.
During the past decade, the insect growth regulator pyriproxyfen has been the most used insecticide for controlling the California red scale (CRS), Aonidiella aurantii (Maskell), an important pest in citrus groves worldwide. The aim of the present research was to develop bioassays for determining the effect of pyriproxyfen on developing stages and embryogenesis of CRS that can serve as baselines for monitoring resistance. Pyriproxyfen was very effective against first- and second-instar nymphs of a susceptible strain of CRS; 0.1 and 0.2 mg AI L(-1), resulting in 80 and 100% mortality of first-instar nymphs, and in 62.5 and 91.7% mortality of second-instar nymphs respectively. According to probit analysis, the LC(50) and LC(90) values of pyriproxyfen for first-instar nymphs were 0.03 and 0.15 mg AI L(-1), and for second-instar nymphs they were 0.05 and 0.25 mg AI L(-1) respectively. Pyriproxyfen was quite effective on first-instar nymphs of a CRS field strain originating from a citrus grove where two successive applications of the compound had been applied. Mortality rates were 86 and 100% at concentrations of 0.2 and 0.4 mg AI L(-1) respectively. Pyriproxyfen suppressed embryogenesis when CRS females were treated with pyriproxyfen. Young CRS females treated with 1.0 and 5.0 mg AI L(-1) pyriproxyfen produced 6.6 N(1)/F and 2.4 N(1)/F as compared with 10.9 N(1)/F in untreated control. 相似文献
6.
Construction of a genetic map of melon with molecular markers and horticultural traits, and localization of genes associated with ZYMV resistance 总被引：12，自引：0，他引：12
Yael Danin-Poleg Yaakov Tadmor Galil Tzuri Noa Reis Joseph Hirschberg Nurit Katzir 《Euphytica》2002,125(3):373-384
Abstract: A partial linkage map of melon was constructed from a cross between PI414723 and Dulce. Twenty-two SSR, 46RAPD,
2 ISSR markers and four horticultural markers [female flower form (a), Fusarium resistance, striped epicarp (st), and fruit flesh pH (pH)] were analyzed in an F2/F3 population to produce a map spanning 14 linkage groups. We report for the first time map positions for the st, a, and pH genes. One SSR marker was tightly linked to pH. Mapping the a gene for the female flower form to molecular linkage group 4 enabled the merging of the map of horticultural traits with
the of molecular markers in this region. Using the 22 SSR markers of this map, two of the three postulated ZYMV resistance
genes were located using a BC1 population (PI414723 recurrent parent). One SSR marker was tightly linked to a ZYMV resistance gene, designated Zym-1.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
7.
Konstantinos Tsiamis Ernesto Azzurro Michel Bariche Melih E. inar Fabio Crocetta Olivier De Clerck Bella Galil Fernando Gmez Razy Hoffman Kathe R. Jensen Lyudmila Kamburska Joachim Langeneck Martin R. Langer Ya'arit Levitt‐Barmats Marco Lezzi Agnese Marchini Anna Occhipinti‐Ambrogi Henn Ojaveer Stefano Piraino Noa Shenkar Maria Yankova Argyro Zenetos Ante
uljevi&#x; Ana Cristina Cardoso 《水产资源保护:海洋与淡水生态系统》2020,30(4):794-845
- The disproportionately low presence of marine species in the list of invasive alien species (IAS) of Union concern of the European Union (EU) Regulation 1143/2014 does not fully acknowledge the threat they pose to the EU marine environment.
- In this study, the first EU‐scale Horizon Scanning (HS) focusing on marine alien species was performed, aiming to deliver a ranked list of species that should be of high priority for risk assessment (Article 5 of the EU IAS Regulation).
- Species absent from or with a limited distribution in EU marine waters were targeted. In total, 363 alien species were initially screened for HS by a panel of experts, including a broad range of taxonomic groups. Species were scored for their likelihood of arrival, establishment, spread, and impact in EU waters.
- A consensus workshop ranked 267 species, including a subset of 26 prioritized species. These species are considered to be mainly introduced by shipping (fouling and ballast water), via the Suez Canal, and aquaculture activities. The 26 priority species were also scrutinized in terms of feasibility of their management; 18 of them were suggested for performing risk assessments on the basis of the EU IAS Regulation.
- Since biological invasions are dynamic and connected with accelerated globalization and diversified human activities, we recommend HS to be repeated periodically to review the species already listed and assess new ones.
8.
Ilana Rogachev Vladimir Kampel Vadim Gusis Noa Cohen Jonathan Gressel Abraham Warshawsky 《Pesticide biochemistry and physiology》1998,60(3):133
The effect of herbicides that act by generating active oxygen species is often mitigated by the enzymes of the Halliwell-Asada oxygen detoxification pathway. Use of compounds interfering with this pathway synergizes herbicides, allowing the killing of weeds at lower herbicide doses. We have used different dithiocarbamate chelators (Dtcs) capable of removing copper from superoxide dismutase, the first enzyme of the pathway, suppressing its action. Dtcs with different hydrophilic-lipophilic properties (sodium salts of ethyl (2-(2-ethoxyethoxy)ethyl)-, butyl (2-(2-ethoxyethoxy)ethyl) -, hexyl (2-(2- ethoxyethoxy)ethyl)-, and dibutyldithiocarbamic acids) were synthesized so that they might penetrate plant cuticles better than sodium diethyldithiocarbamate. Octanol-water distribution ratios and the stabilities of their copper complexes were determined. All Dtcs tested had a high affinity for copper. The Dtcs did not prevent iron-catalyzed Fenton reaction leading to hydroxyl radical productionin vitro. Therefore they would not protect plants from the oxidative damage caused by herbicide, as do compounds that complex iron and thereby prevent the phytotoxic iron-catalyzed Fenton reaction. These amphiphilic compounds show some synergistic activityin vivo, with paraquat as well as lactofen, herbicides that generate active oxygen species by different mechanisms. The results demonstrate that dithiocarbamates have potential as synergists for oxidant-generating herbicides. 相似文献
9.
Marina ZANIN Noa GONZALEZ-BORRAJO Cuauhtémoc CHÁVEZ Yamel RUBIO Bart HARMSEN Claudia KELLER Pablo VILLALVA Ana Carolina SRBEK-ARAUJO Leonora Pires COSTA Francisco PALOMARES 《Integrative zoology》2021,16(1):2-18
Modern and paleoclimate changes may have altered species dynamics by shifting species’ niche suitability over space and time. We analyze whether the current genetic structure and isolation of the two large American felids, jaguar (Panthera onca) and puma (Puma concolor), are mediated by changes in climatic suitability and connection routes over modern and paleoclimatic landscapes. We estimate species distribution under 5 climatic landscapes (modern, Holocene, last maximum glaciations [LMG], average suitability, and climatic instability) and correlate them with individuals’ genetic isolation through causal modeling on a resemblance matrix. Both species exhibit genetic isolation patterns correlated with LMG climatic suitability, suggesting that these areas may have worked as “allele refuges.” However, the jaguar showed higher vulnerability to climate changes, responding to modern climatic suitability and connection routes, whereas the puma showed a continuous and gradual transition of genetic variation. Despite differential responsiveness to climate change, both species are subjected to the climatic effects on genetic configuration, which may make them susceptible to future climatic changes, since these are progressing faster and with higher intensity than changes in the paleoclimate. Thus, the effects of climatic changes should be considered in the design of conservation strategies to ensure evolutionary and demographic processes mediated by gene flow for both species. 相似文献
10.
Hounsfield units are a useful predictor of pleural effusion cytological type in dogs but not in cats 
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下载免费PDF全文 Sarah J. Woods Mathieu Spriet Noa Safra Derek D. Cissell Dori L. Borjesson 《Veterinary radiology & ultrasound》2018,59(4):405-411
All categories of pleural effusion subjectively display as soft tissue opacity on computed tomography (CT). Quantitative measurement using Hounsfield units (HU) has the potential to bring additional information regarding the nature of the fluid in a noninvasive way. The purposes of this retrospective cross‐sectional analytical study were to compare Hounsfield units of different pleural effusion categories in dogs and cats, assess association between specific cytologic parameters and Hounsfield units, and evaluate the effect of dependent vs. nondependent aspect of the effusion pool on Hounsfield unit. A total of 111 patients (74 dogs and 37 cats) with pleural effusion, that underwent thoracic CT and diagnostic thoracocentesis, were included in the study. Effusions were cytologically categorized as exudate, transudate, modified transudate, hemorrhage, or chyle. Significant differences existed in Hounsfield units between categories in dogs (P < 0.0001) but not in cats (P = 0.334). Canine chylous effusion (6.1 ± 4.7 HU (mean ± standard deviation)) and transudate (5.6 ± 2.0) were significantly lower than exudate (20.3 ± 9.5) and hemorrhage (21.4 ± 9.2). No significant differences were found between modified transudate (13.6 ± 10.3) and other categories. Significant, weak linear correlation was identified in dogs between Hounsfield units and total protein (P = 0.018, R2 = 0.089), red blood cells (P = 0.021, R2 = 0.077), and total nucleated cells (P = 0.013, R2 = 0.089). The Hounsfield units of dependent effusion was not significantly higher than the nondependent effusion, except for canine chylous effusion (P = 0.008). Fourteen Hounsfield units was identified as the most clinically useful threshold: <14 HU identified transudate or chylous effusion with a sensitivity of 100% and a specificity of 69%. A threshold >14 HU had a specificity of 100% and a sensitivity of 69% for identifying exudate, modified transudate, or hemorrhage. 相似文献