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111.
Oxylipins are a large and diverse family of fatty acid derivatives exhibiting different levels of oxidation of the carbon chain. They are involved in many biological functions in mammals, plants and diatoms. In this last group of organisms, they are suggested to play a role in the reproductive failure of copepod predators, showing clear pro-apoptotic effects on newborn nauplii. In this work, these compounds were tested for the ability to induce mitotic arrest in sea urchin embryos. We show for the first time that oxylipins have an increased efficacy in their corresponding methylated form. Natural oxylipins were also used as an inspiration for the rational design and synthesis of stable chemical analogs with apoptotic activity against tumor cell lines. This approach led to the synthesis of the linear C15-ketol (22) that was shown to induce apoptosis in human leukemia U-937 cells. These results are proof of the concept of the use of eco-physiological considerations as a platform to guide the search for novel drug candidates.  相似文献   
112.
A field study on assessment of crop establishment methods on yield, economics and water productivity of rice cultivars under upland and lowland production ecologies was conducted during wet seasons (June–November) of 2012 and 2013 in Eastern Indo-Gangetic Plains of India. The experiment was laid-out in a split-plot design (SPD) and replicated four times. The main-plot treatments included three crop establishment methods, viz. dry direct-seeded rice (DSR), system of rice intensification (SRI) and puddled transplanted rice (PTR). In sub-plots, five rice cultivars of different groups like aromatic (Improved Pusa Basmati 1 and Pusa Sugandh 5), inbreds (PNR 381 and Pusa 834) and hybrid (Arize 6444) were taken for their evaluations. These two sets of treatments were laid-out simultaneously in two production ecologies, upland and lowland during both years. In general, lowland ecology was found favourable for rice growth and yield and resulted in 13.2% higher grain yield as compared to upland ecology. Rice grown with SRI method produced 19.4 and 7.0% higher grain yield in 2012 and 20.6 and 7.1% higher in 2013, over DSR and PTR. However, PTR yielded 13.1 and 14.5% higher grain over DSR during 2012 and 2013, respectively. On an average, Arize 6444 produced 26.4, 26.9, 28.9 and 54.7% higher grain yield as compared to PS 5, P 834, PNR 381 and IPB1, respectively. Further, the interaction of production ecologies × crop establishment methods revealed that, in upland ecology, SRI recorded significantly higher grain yield as compared to PTR and DSR, but in lowland, grain yield resulting from SRI was similar to the yield obtained with PTR and significantly higher than DSR. The latter two methods (PTR and DSR) yielded alike in lowland ecology in both study years. The production ecologies × crop establishment methods × cultivars interaction on grain yield showed that the growing of Arize 6444 cultivar using SRI method in upland ecology resulted in the higher grain yield (8.87 t/ha). But the cost of production was also highest in SRI followed by PTR and DSR across production ecologies and cultivars. Cultivation of hybrid (Arize 6444) involved higher cost of production than all other cultivars. Irrespective of crop establishment methods and cultivars, gross returns, net returns and B:C ratio were significantly higher in lowland compared to upland ecology. Owing to higher grain yield, SRI method fetched significantly higher gross returns and net returns over PTR and DSR. Average increase in net return with Arize 6444 was 68.8, 41.0, 37.7 and 33.1% over IPB 1, PNR 381, P 834 and PS 5, respectively. There was a saving of 30.7% water in SRI and 19.9% in DSR over PTR under upland ecology. Similarly in lowland ecology, water saving of 30.2% was observed in SRI and 21.2% in DSR over PTR. Due to higher yield and saving on water, SRI returned significantly higher total water productivity (TWP) (5.9 kg/ha-mm) as compared to DSR (3.5 kg/ha-mm) and PTR (3.6 kg/ha-mm) under upland ecology. In lowland ecology, also SRI (6.2 kg/ha-mm) resulted in higher TWP as compared to other two methods. However, DSR gave significantly higher TWP as compared to PTR. Among cultivars, hybrid Arize 6444 recorded the highest TWP in both upland and lowland production ecologies across crop establishment methods. Hence, growing of hybrid Arize 6444 with SRI method can enhance rice productivity and water-use efficiency in lowland and upland production ecologies of Eastern Indo-Gangetic Plains and in other similar regions.  相似文献   
113.
This study identified the role of milling and parboiling on arsenic (As) content and its species in large numbers of rice samples. Total As contents were 108 ± 33 μg/kg in polished rice grains (PR), 159 ± 46 μg/kg in unpolished rice grains (UR), 145 ± 42 μg/kg in parboiled polished rice grains (PPR) and 145 ± 44 μg/kg in parboiled unpolished rice grains (PUR). The percentages of inorganic As (iAs) were 66% ± 8% in PR and from 72% to 77% in other grain categories. The polishing process reduced the As content in the rice grains, removing outer part of the UR with high amount of As, whereas the parboiling technique transferred the semimetal content within the grain. Total As and iAs contents were not significantly different in UR, PPR and PUR, homogenizing its distribution inside the grains. The results allowed to understand how different operations affect As fate and its chemical forms in grains.  相似文献   
114.
The commercial oil cake produced during expeller pressing of maize germ, was extracted with n-hexane and 80 percent ethanol followed by seiving to remove undesirable materials. In defatted maize germ oil cake (DMGOC): protein, starch, fat, crude fiber (CF) and ash were respectively 24.69, 36.55, 5.68, 7.56 and 3.90 percent and they decrease after processing except ash, which increased slightly. It contains better quality protein having only 3 percent zein and 47 percent albumin. Its amino acids like lysine and tryptophan and biological value (BV) were higher than that of whole maize grain, and was comparable with that of the amino acid requirement of preschool children and casein diets both. Its digestible energy (DE) was lower compared with whole maize grain as well as the casein diets. After processing albumin, globulin and zein decreased whereas glutelin and the residual fraction increased. Not much differences were observed in chemical composition and different amino acids, in vitro protein digestibility (IVPD), true digestibility (TD), BV and DE improved after processing.  相似文献   
115.
External otitis is a diffuse inflammation around the external auditory canal and auricle, which is often occurred by microbial infection. This disease is generally treated using antibiotics, but the frequent occurrence of antibiotic resistance requires the development of new antibiotic agents. In this context, unexplored bioactive natural candidates could be a chance for the production of targeted drugs provided with antimicrobial activity. In this paper, microbial pathogens were isolated from patients with external otitis using ear swabs for over one year, and the antimicrobial activity of the two methanol extracts from selected marine (Dunaliella salina) and freshwater (Pseudokirchneriella subcapitata) microalgae was tested on the isolated pathogens. Totally, 114 bacterial and 11 fungal strains were isolated, of which Staphylococcus spp. (28.8%) and Pseudomonas aeruginosa (P. aeruginosa) (24.8%) were the major pathogens. Only three Staphylococcus aureus (S. aureus) strains and 11 coagulase-negative Staphylococci showed resistance to methicillin. The two algal extracts showed interesting antimicrobial properties, which mostly inhibited the growth of isolated S. aureus, P. aeruginosa, Escherichia coli, and Klebsiella spp. with MICs range of 1.4 × 109 to 2.2 × 1010 cells/mL. These results suggest that the two algae have potential as resources for the development of antimicrobial agents.  相似文献   
116.
The reactivity of bovine foetal intestine to some acetylcholine derivatives is compared with the response to acetylcholine. Qualitatively similar responses are observed between the bovine intestine after mid-foetal life and intestinal tissue from adult animals. A lower reactivity of the foetal preparations could be partly explained by the existence of different levels of cholinesterase in the tissues at different times during embryogenesis. Foetal intestine reacts with different intensity to the cholinergic agents tested.
Kurzfassung Man studiert die Reaktion des Fötusdarmes von Rind auf einige Azethylcholin Derivate im Vergleich mit Azethylcholin. Das Studium erklärt dass der nach der Mitte des embryonalen Lebens Rinddarm und der von erwachsenen Tieren Darm, auf gleiche Weise sich betragen. Eine kleinere Reaktion der Fötuspräparate möchte mit der Anwesenheit von verschiedenen Cholinesterase Konzentrationen in den Geweben während der embryonalen Entwicklung, teilweise erklärt werden. Der Fötusdarm reagiert auf die cholinergischen geprüften Mittel mit verschiedener Intensität.

Resume L'A. étude la réactivité de l'intestin foetal de boeuf à quelques dérivés de l'acétylcholine en comparaison du médiateur cholinergique. Qualitativement des réponses similaires ont été observées dans l'intestin aprés la moitié de la vie foetale et celui des animaux adults. La plus petite réactivité des préparations foetales pourrait être expliquée partiellement par l'existence de concentrations différentes de cholinestérase tissulaire dans de différentes périodes du dévelopement embryonnaire. L'intestin foetal réagit avec diverse intensité aux médicaments cholinergiques éxaminés.

Riassunto L'A. studia la reattività dell'intestino fetale bovino ad alcuni derivati dell'acetilcolina paragonandola con la risposta evocata dal mediatore colinergico. Qualitativamente vengono riscontrate risposte simili tra l'intestino bovino proveniente da feti che hanno superato la metà della vita embrionale e quello di animali adulti. La minore reattività dei preparati fetali potrebbe essere parzialmente interpretata dal reperimento di differenti concentrazioni di colinesterasi tessutali a tempi diversi di sviluppo embrionale. L'intestino fetale reagisce con diversa intensità agli agenti colinergici saggiati.
  相似文献   
117.
The factors affecting the adoption of modern varieties(MVs) of rice and impact on poverty in Odisha, India were discussed. A total of 363 households from Cuttack and Sambalpur districts of Odisha via multistage sampling technique participated in the survey. The Cragg's Double hurdle model was used to model the determinants of adoption and intensity of adoption of MVs of rice, and the propensity score matching was used to analyze the impact of adoption on poverty. The results showed that age, education, risk aversion, land size, yield, perception of MVs as high yielding, resistant to diseases and availability of MVs positively influenced the decision to adopt. However, variables such as household size, experience of a farmer, off-farm job participation, amount of credit received, cost of seeds, insecticides and fertilizers negatively influenced the adoption of MVs. Intensity of adoption of MVs was negatively influenced by experience of a farmer, cost of fertilizer and marketability of MVs, and positively affected by household size, risk aversion, land size, cost of insecticides, perception of MVs as high yielding and availability of MV seeds. Poverty incidence, gap and severity were high among non-adopters to adopters of MVs. After matching adopters and non-adopters of MV groups using four different algorithms of nearest neighbour matching, stratification matching, radius matching and kernel matching, the impact of MV adoption resulted in higher per capita monthly household expenditure by about US$ 52.82 to US$ 63.17.  相似文献   
118.
Starch has been the most popular and economic size material. Synthetic binders have also been developed to be used as size material to improve weaving loom efficiency. Some synthetic size materials have got restrictions in use mainly because of ecological reasons. In the recent years, many modifications have come up in the starch as a sizing agent. Different modification can give different properties, which can be suited for a particular application. In the present study, for comparative analysis of different varieties of natural starch, modified starch and synthetic size material have been evaluated and mechanical properties like cohesion power, adhesion power, abrasion resistance, bending rigidity etc. were studied. PVA shows best properties among all size material. Among modified starch, starch ester shows better properties.  相似文献   
119.
The present investigation was carried on a 8 parent diallel of mungbean involving 28 F1's and 28 F2's excluding reciprocals grown at three different locations including Meerut, Ludhiana and Hissar. Three different analyses including combining ability, graphical and component analysis were utilized.From the combining ability analysis over different environments it was reported that g.c.a. effects are relatively more consistent over environments than s.c.a. effects. The parents P3 and P5 were ranked as the best general combiners and the cross P5 × P7 was the good specific combination in both the diallel sets. The graphical analysis suggested that high protein content is governed by dominant genes. Further all the analyses revealed that non-additive variance was mostly responsible for this character. Thus two methods, including biparental mating system among the selected F2/F3 plants from P5×P7 cross; and modified diallel selective mating system for the selected parents with good or average general combining ability were suggested. From these populations the desirable combinations with high protein content and other desirable attributes, be selected which can constitute a future variety.  相似文献   
120.
The 2020 Student Debates of the Entomological Society of America (ESA) were live-streamed during the Virtual Annual Meeting to debate current, prominent entomological issues of interest to members. The Student Debates Subcommittee of the National ESA Student Affairs Committee coordinated the student efforts throughout the year and hosted the live event. This year, four unbiased introductory speakers provided background for each debate topic while four multi-university teams were each assigned a debate topic under the theme ‘Technological Advances to Address Current Issues in Entomology’. The two debate topics selected were as follows: 1) What is the best taxonomic approach to identify and classify insects? and 2) What is the best current technology to address the locust swarms worldwide? Unbiased introduction speakers and debate teams began preparing approximately six months before the live event. During the live event, teams shared their critical thinking and practiced communication skills by defending their positions on either taxonomical identification and classification of insects or managing the damaging outbreaks of locusts in crops.  相似文献   
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