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61.
62.
Uncultivated plants are an important part of agricultural systems and play a key role in the survival of rural marginalized groups such as women, children, and the poor. Drawing on the gender, environment, and development literature and on the notion of women’s social location, this paper examines the ways in which gender, ethnicity, and economic status determine women’s roles in uncultivated plant management in Ixhuapan and Ocozotepec, two indigenous communities of Veracruz, Mexico. The first is inhabited by Nahua and the second by Popoluca peoples. Information was gathered through group and individual interviews and a food frequency survey. Results show that the gender ideology prevailing in each community, resulting from distinct ethnic affiliations and economic contexts, shapes women’s plant management. In Ixhuapan, Nahua women are used to leaving their community to generate income, while in Ocozotepec men are considered the main breadwinners and are the mediators between Popoluca households and the larger society. Nahua women gather quelites at the cornfields more often than their men, and more often than their female counterparts in Ocozotepec. They also manage and sell plants from their homegardens at higher percentages than Popoluca women. However, women in both communities use intensely the plants of their homegardens and play a key role in biodiversity conservation and cultural permanence.
Veronica Vazquez-GarciaEmail:
  相似文献   
63.
Canine cutaneous mast cell tumours (cMCTs) of the pinna have been associated with an aggressive biological behaviour, although data remain scarce. The knowledge acquired over the past years on histologic gradings, and the value of lymph node (LN) staging, may help in better characterizing this anatomical presentation. The first aim was to describe the frequency, location, and histologic appearance of LN metastases in cMCT of the pinna. A second aim was to evaluate prognosis. Medical records of dogs with cMCT of the pinna, that underwent tumour and sentinel (SLN) or regional LN (RLN) excision, were reviewed. The influence of potential prognostic variables on time to progression (TTP) and tumour-specific survival (TSS) was investigated. Thirty-nine dogs were included: 19 (48.7%) had Kiupel high-grade (K-HG) and 20 (51.3%) had low-grade (K-LG) MCTs. Eighteen (46.1%) dogs underwent SLN mapping: the superficial cervical LN was at least one of SLN in 17 (94.4%) cases. Twenty-two (56.4%) dogs had LN metastases; the superficial cervical LN was always involved. On multivariable analysis, only K-HG was associated with increased risk of progression (p = .043) and tumour-related death (p = .021). Median TTP and TSS were 270 and 370 days in K-HG, respectively; these were not reached in dogs with K-LG tumours (p < .01). cMCTs of the pinna are often K-HG and are also associated with a higher frequency of LN metastasis; however, we confirmed the independent prognostic value of histologic grading. A multimodal treatment may lead to favourable long-term outcome. Moreover, the superficial cervical LN is most often the SLN.  相似文献   
64.
Meiotic recombination in budding yeast requires two RecA-related proteins, Rad51 and Dmc1, both of which form filaments on DNA capable of directing homology search and catalyzing formation of homologous joint molecules (JMs) and strand exchange. With use of a separation-of-function mutant form of Rad51 that retains filament-forming but not JM-forming activity, we show that the JM activity of Rad51 is fully dispensable for meiotic recombination. The corresponding mutation in Dmc1 causes a profound recombination defect, demonstrating Dmc1's JM activity alone is responsible for meiotic recombination. We further provide biochemical evidence that Rad51 acts with Mei5-Sae3 as a Dmc1 accessory factor. Thus, Rad51 is a multifunctional protein that catalyzes recombination directly in mitosis and indirectly, via Dmc1, during meiosis.  相似文献   
65.
66.
Fusarium verticillioides is best known for its worldwide occurrence on maize resulting in highly variable disease symptoms, ranging from asymptomatic to severe rotting and wilting and fumonisin production. The aim of this study was to investigate the influence of hybrid genotypes in the early stages of F. verticillioides infection, and the role of fumonisins as effectors in the outcome of this complex interaction. Disease symptoms, growth parameters, root morphology, and fungal colonization were evaluated at 7, 14, and 21 days after planting in seedlings from maize seeds of resistant (RH) and susceptible (SH) hybrids inoculated with F. verticillioides or watered with solutions of fumonisins. F. verticillioides induced growth enhancement or retardation depending on the plant genetic background and the fungal colonization rate, while fumonisins caused severe reduction in biomass and fitness. Seedlings watered with high fumonisin concentrations displayed lesions similar to those seen in F. verticillioides maize seedling disease, and also elicited inhibitory effects on root growth and morphology and on functional properties. In summary, these data strongly suggest a dual role for fumonisins in the F. verticillioides-maize interaction, acting as pathogenic factors at high concentrations, or triggering the plant detoxification mechanisms at low levels.  相似文献   
67.
ObjectiveTo evaluate the evidence of analgesic efficacy of tramadol for the management of postoperative pain and the presence of associated adverse events in dogs.Databases usedA comprehensive search using PubMed/MEDLINE, LILACS, Google Scholar and CAB databases with no restrictions on language and following a prespecified protocol was performed from June 2019 to July 2020. Included were randomized controlled trials (RCTs) performed in dogs that had undergone general anesthesia for any type of surgery. Two authors independently classified the studies, extracted data and assessed their risk of bias using Cochrane’s tool. RevMan and GRADE methods were used to rate the certainty of evidence (CoE).ConclusionsOverall 26 RCTs involving 848 dogs were included. Tramadol administration probably results in a lower need for rescue analgesia versus no treatment or placebo [moderate CoE; relative risk (RR): 0.47; 95% confidence interval (CI): 0.26–0.85; I2 = 0%], and may result in a lower need for rescue analgesia versus buprenorphine (low CoE; RR: 0.50; 95% CI: 0.20–1.24), codeine (low CoE; RR: 0.75; 95% CI: 0.16–3.41) and nalbuphine (low CoE; RR: 0.05; 95% CI: 0.00–0.72). However, tramadol administration may result in an increased requirement for rescue analgesia versus methadone (low CoE; RR: 3.45; 95% CI: 0.66–18.08; I2 = 43%) and COX inhibitors (low CoE; RR: 2.27; 95% CI: 0.68–7.60; I2 = 45%). Compared with multimodal therapy, tramadol administration may make minimal to no difference in the requirement for rescue analgesia (low CoE; RR: 1.12; 95% CI: 0.48–2.60; I2 = 0%). Adverse events were inconsistently reported and the CoE was very low. The overall CoE of the analgesic efficacy of tramadol for postoperative pain management in dogs was low or very low, and the main reasons for downgrading the evidence were risk of bias and imprecision.  相似文献   
68.
Penaeus monodon juveniles (average WEIGHT = 1.32 g) were kept in individual 2 l perforated plastic containers, 10 of which were placed in each of the twenty-four 50 l rectangular wooden-glass aquaria supplied with seawater filtered through a sand-gravel filter (32–34 ppt; 26.5–29.0°C; pH, 7.6–8.2) at 0.8–1.01 l/min. Eight diets were prepared containing 25–60% protein and fed at 10% of the body weight/day for the first 2 weeks and 8% for the succeeding 4 weeks.

Shrimps fed the 40% protein diet produced the best growth, feed conversion ratio (FCR), protein efficiency ratio (PER) and survival rate. However, shrimps fed the 30, 35 and 45% protein diets produced comparable results. The protein content of the shrimps was directly related to the level of protein diet up to 50%; whereas fat content seemed to be inversely related up to 50% protein diet.  相似文献   

69.
In a Biofloc Technology System (BFT), there is constant biofloc formation and suspended solids accumulation, leading to effects on water quality parameters that may affect the growth performance of cultured shrimp. This study aimed to analyse during biofloc formation the effect of different total suspended solids (TSS) levels on water quality and the growth performance of Litopenaeus vannamei shrimp in a BFT system. A 42‐day trial was conducted with treatments of three ranges of TSS: 100–300 mg L?1 as low (TL), 300–600 as medium (TM) and 600–1000 as high (TH). The initial concentrations of 100 (TL), 300 (TM) and 600 mg L?1 (TH) were achieved by fertilization before starting the experiment. Litopenaeus  vannamei juveniles with an average weight of 4.54 ± 1.19 g were stocked at a density of 372 shrimp m?3. Physical and chemical water parameters and shrimp growth performance were analysed. After 6 weeks, TSS mean concentrations were 306.37, 532.43 and 745.2 mg L?1 for, respectively, TL, TM and TH treatments. Significant differences (P < 0.05) were observed in TSS, settleable solids, pH, alkalinity and nitrite, especially between the TL and TH treatments. Similarly, differences (P < 0.05) were observed in the growth performance parameters, specifically final weight, survival, feed conversion and productivity. The water quality parameters at lower range of total suspended solids concentration (TL) treatment resulted in a better performance of L. vannamei in the BFT system. The maintenance at range of 100–300 mg L?1 TSS is thus important to the success of shrimp culture.  相似文献   
70.
We studied the input of ammonium coming from the dissolution of food pellets commonly used in salmon farming as well as its potential for mineralization via ammonification and ammonium oxidation by natural bacterioplankton communities. Through experiments in central and southern Chile, we evaluated the potential for photo‐ and bio‐ammonification of food pellets in surface and subsurface waters (30 m depth) using irradiated (PAR + UV; IPS) and non‐irradiated dissolved‐pellet solutions (NIPS). Ammonium release was observed in both IPS and NIPS treatments and occurred at short time scales (<2 hr). Experiments in southern Chile during late winter showed high rates of pellet ammonium release in surface waters (up to 3.8 µmol L?1 min?1) compared with deeper samples (30 m depth). In contrast, in spring higher rates were observed at 30 m depth and reached up to 45 µmol L?1 min?1 while in surface waters they accounted for 9 µmol L?1 min?1. Ammonium oxidizing bacteria and archaea showed seasonal variability, but archaea were detected in all experiments reaching high potential activity, based in RT‐qPCR of functional genes expression copy numbers, in IPS treatments during the winter season in Chiloé. Overall, our results indicate that food pellets can be a source of ammonium, which can exceed by two orders of magnitude the average natural concentrations commonly found in the euphotic layer in coastal environments. The ammonium enrichment from dissolved pellet solutions was rapidly consumed by microbial communities including nitrifying assemblages. This has implications for the evaluation of aquaculture nutrient input and its recycling in the water column in areas highly impacted by climate change and aquaculture pressure.  相似文献   
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