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1.
Xinxiangyou 77wasdevelopedatHHRRCusingaro maticcytoplasmicmalesterilelineXingxiangAandnonaromaticrestorerlineMinghui 77.ItwasextensivelytestedandapprovedforreleasetofarmersbytheHunanProvincialCropVarietyReleaseCommitteeinFebruary ,1997.XingxiangA ,improvedfromthefirstaromaticCMSlineXiangxiang 2A ,isanotheraromaticCMSlinedevelopedbyHHRRC .ThenewlinehasstablemalesterilityandbetteroutcrossingcharacteristicsthanXiangx iang 2A .Minghui77,developedbytheSanmingAgricul turalInstitute ,Fu…  相似文献   

2.
Morphology and inheritance of a new rice leaf death mutant   总被引：4，自引：0，他引：4  
A new mutant showing successive leaf death was selected in a mutmion populalion from an indica rice variety Zhongxian 3037 trealed with 94^Co-γ rays. The leaves of this rnutanl began lodie on the emergence of tlle third leaf tip, and all leaves died sooner alter flowering. Consequently,  相似文献   

3.

Background

The hypothesis that distance matters but that in recent years geographical proximity has become less important for research collaboration was tested. We have chosen a sample–authors at German immunological institutes–that is relatively homogeneous with regard to research field, language and culture, which beside distance are other possible factors influencing the willingness to co-operate. We analyse yearly distributions of co-authorship links between institutes and compare them with the yearly distributions of distances of all institutes producing papers in journals indexed in the Science Citation Index, editions 1992 till 2002. We weight both types of distributions properly with paper numbers.

Results

One interesting result is that place matters but if a researcher has to leave the home town to find a collaborator distance does not matter any longer. This result holds for all years considered, but is statistically most significant in 2002. The tendency to leave the own town for collaborators has slightly increased in the sample. In addition, yearly productivity distributions of institutes have been found to be lognormal.

Conclusion

The Internet did not change much the collaboration patterns between German immunological institutes.
  相似文献   

4.
The analysis of 4 commonly available amaranth varieties (Amaranthus K343, RRC1011, K433, K432) revealed the presence of all three major phytosterols (beta-sitosterol, campesterol, stigmas-terol) with a total sterol content being several fold higher than those found in other studied plants. Substantial differences in total phytosterol content and beta-sitosterol content were found between the amaranth varieties. The most commonly cultivated amaranth variety in the United States, i.e., Amaranthus K343 was found to possess the highest levels of phytosterols of the varieties tested. The possibility of screening for superior amaranth varieties with various health properties is outlined.  相似文献   

5.
Courtship and spawning behaviors of coral reef fishes are very complex, and sufficient sampling effort and proper methods are required to draw informed conclusions on their mating systems that are grounded in contemporary theories of mate choice and sexual selection. We reviewed the recent study by Karkarey et al. (BMC Ecol 17:10, 2017) on the spawning behavior of Squaretail coralgrouper (Plectropomus areolatus) from India and found no evidence to support their findings of alternative reproductive tactics, unique school-spawning involving a single male with multiple females, or inverse size-assortment. The study lacks scientific credibility due to a lack of rigor in the methodology used, misinterpretation of observed behaviors, misinterpretation of the literature, and insufficient data. Their approach led the authors to produce spurious results and profound, invalid conclusions that violate the most basic assumptions of mate choice and sexual selection theory as applied to mating systems in marine fishes.  相似文献   

6.
Plant Foods for Human Nutrition - Prebiotics are regarded as the non-digestible food constituents that are selectively consumed by health-promoting bacteria (probiotics). In fact, a number of...  相似文献   

7.
Plant Foods for Human Nutrition - Selenium supplementation in humans has been suggested for the prevention of chronic diseases including cardiovascular disease, cancer, and neurodegenerative...  相似文献   

8.
Under Mediterranean environments, farmers usually prefer to sow barley rather than wheat as it is generally believed that barley yields more under stressful conditions. As terminal stresses such as high temperature and water are common constraints in Mediterranean regions, higher grain weight stability may confer a clear advantage in order to maintain higher yields. The objective of the present study was to compare the stability in terms of grain weight and its components for barley, bread wheat, and durum wheat, exploring a wide range of nitrogen and water availabilities in experiments conducted in a Mediterranean region. Grain weight ranged from 23.8 to 47.7 mg grain−1, being higher for durum wheat than barley and bread wheat. Durum wheat presented higher variability both in maximum grain filling rate and duration of grain filling period than bread wheat or barley. The three species responded similarly in terms of grain nitrogen content to changes in the environmental conditions explored. It is concluded that in terms of grain weight barley is as stable as bread wheat. However, durum wheat presented a lower stability than barley and bread wheat.  相似文献   

9.
Nutritious value of seed storage protein is low due to deficiency in essential amino acid contents. Cereals are mainly deficient in lysine and legumes in sulfur-containing amino acids ( methionine and cysteine). So far, several sufur-rich seed protein genes have been isolated and the essential amino acid contents of seed proteins were increased in transgenic tobacco and Brassica napus.  相似文献   

10.
In order to assess the potential of the hydroxy-containing polyamic acid (PHAA) synthesized from 3,3′-dihydroxy benzidine and pyromellitic dianhydride for a fire-safe polymer, the cyclization pathway of PHAA has been investigated using a model compound prepared from 2-aminophenol and phthalic anhydride. The reaction was monitored by1H-nuclear magnetic resonance. N-(2-hydroxyphenyl)phthalamic acid is converted to N-(2-hydroxyphenyl)phthalimide at ca. 175°C, showing endothermic reaction. The imide structure is rearranged to the benzoxazole structure over ca. 400°C. These results are similar with that of PHAA. According to pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) data, water and carbon dioxide are released during the cyclization and rearrangement reaction. One DMAc molecule is complexed with one carboxyl acid group in PHAA, which accelerates the imidization process to release more easily the flame retardant, water.  相似文献   

11.
Field mold (FM) can easily deteriorate the preharvest soybean in the field, and Fusarium moniliforme is demonstrated as the dominant pathogenic fungi. Metabolomics is a powerful tool to reveal the resistance mechanism in response to microbial infection. Therefore, in this research, the Design of Experiment (DOE) model was developed to optimize the extraction solvent combinations for metabolomic study of soybean seed and pod based on gas chromatography–mass spectrometry (GC–MS). Combined with the number of extracted peaks and the peak area of common substances, the extraction efficiency of different solvent was analyzed by multivariate statistical analysis. The result showed that isopropanol/water/methanol (1:1:1 and 1:1:4, v/v/v) mixture was highly efficient for metabolites extractions of soybean seed and pod, respectively. Additionally, the potential metabolites and pathways concerned in FM resistance were explored by the optimized extraction solvent system based on metabolomics analysis. Amino acid metabolism in soybean seed was disturbed by F. moniliforme and metabolic pathways related to energy conversion in soybean pod strongly responded to fungal infection. This study constructs a GC–MS-based metabonomic method for soybean metabolites; comparative analysis of organ-specific metabolomics for soybean fruit could be further applied in soybean metabolomics researches.  相似文献   

12.
One new α-pyrone (nocapyrone R (1)), and three known γ-pyrones (nocapyrones B, H and L (2–4)) were isolated from the culture extract of a Nocardiopsis strain collected from marine sediment. Structures of these compounds were determined on the basis of spectroscopic data including NMR and MS. γ-Pyrones 2–4 were found to induce adiponectin production in murine ST-13 preadipocyte cells but the α-pyrone 1 had no activity. The absolute configuration of the anteiso-methyl branching in 4 was determined by HPLC comparison of a degraded product of 4 with standard samples as a 2:3 enantiomeric mixture of (R)- and (S)-isomers.  相似文献   

13.
Xiangyou 6 3wasdevelopedatHHRRCusingaro maticcytoplasmicmalesterilelineXiangxiang 2Aandnon aromaticrestorerlineMinghui 6 3.ItwasreleasedtofarmersinJan 1995 .Xiangyou 6 3isthefirstquasi aro matichybridriceinChina ,andXiangxiang 2A ,devel opedfromthecrossV2 0A∥V2 0B/MR36 5byHHRRC ,isthefirstaromaticCMSlineinChina .Thehybridhassofarbeenplantedonmorethan 2 0 0 0 0hm2 andseemspop ularwithfarmersandconsumers .Inadditiontobeingaro matic ,thehybridhasgoodgrainquality ,high yieldinga bility…  相似文献   

14.
《Field Crops Research》2001,70(2):139-151
The effects of various crop rotations on the biomass and yield of barley (Hordeum vulgare L.), faba bean (Vicia faba L.), and pea (Pisum sativum L.) grown under Mediterranean conditions were studied during three growing seasons in the semiarid Spanish Central Plateau. The treatments comprised six crop sequences: barley monoculture, fallow–barley (currently used in the area), faba bean–barley, pea–barley, fallow–barley–faba bean, and fallow–barley–pea. The fallow was of 16-month duration. The site is representative of cultivated areas of the Plateau, and the soil has a loam texture. Results concentrate on barley as the main crop. Season distribution of rainfall restricted the effectiveness of the management practices and in consequence there were few differences between rotations. Barley had greater biomass and yield after fallow than after other crops but significant differences were dependent on year. Legumes, an alternative to fallow, increased land use, permitted alternative weed control measures, and reduced the need for fertiliser. The intensification of the fallow–barley cropping system is best achieved by reducing the frequency of fallow and including other crops of relatively small biomass production, thereby minimising the impact on yield of the succeeding barley crop.  相似文献   

15.
A survey of the production, consumption and storage ofKunu was carried out. Some of the information included consumption rate, processing techniques andequipment, producer's status and grains used. About73% consume Kunu daily, 26% occasionally; 1% knowit is produced but may or may not be consuming it. Millet (Pennisetum typhoideum), sorghum (Sorghum vulgare), maize (Zea mays), rice (Oryza sativa) and acha (Digitalis exilis) wereused in its production in decreasing order ofpreference. The grains were used singly or combined;sorghum/millet was the most common combination in aratio of 1:2 (w/w). Steeping was done in ordinary water for 12–72 h, depending on the grain type, in localclay pots, plastic buckets, calabashes or basins or5–7 h in warm water (60–70 °C). The grainswere dry or wet milled with or without spices such asginger, red pepper, black pepper, clove and garlic.Other ingredients introduced included: sweet potatoes,malted rice, malted sorghum and Cadaba farinosacrude extract. Both dry and wet milling was done withgrinding mills, mill stones or mortar and pestle,depending on locality. The product was then cookedinto a thin free flowing gruel. The various types ofkunu were: Kunun zaki, Kunun gyada, Kunun akamu, Kununtsamiya, Kunun baule, Kunun jiko, Amshau and Kunungayamba. Kunun zaki was the most commonly consumed. Production and consumption cut across all socialclasses of the society.  相似文献   

16.
Bioactive compounds were detected in crude extracts of the fungus, Calcarisporium sp. KF525, which was isolated from German Wadden Sea water samples. Purification of the metabolites from the extracts yielded the five known polyesters, 15G256α, α-2, β, β-2 and π (1–5), and five new derivatives thereof, named calcarides A–E (6–10). The chemical structures of the isolated compounds were elucidated on the basis of one- and two-dimensional NMR spectroscopy supported by UV and HRESIMS data. The compounds exhibited inhibitory activities against Staphylococcus epidermidis, Xanthomonas campestris and Propionibacterium acnes. As the antibacterial activities were highly specific with regard to compound and test strain, a tight structure-activity relationship is assumed.  相似文献   

17.
Low cost supplementary products using maize were developed and made using extrusion. -carotene rich sources like curry leaf, carrot, red palm oil were used at different level to increase vitamin A precursor Levels and, therefore, vitamin A. Incorporation of curry leaf powder and carrot powder at 30 percent level and 30:70 blend of red palm oil and groundnut oil were found to be more acceptable than the products made with other levels. These products were tasted for acceptability by preschool children and were analysed for energy, protein, fat and -carotene contents. The control, fresh and stored supplementary products contained 1.707, 1.922, 1.919 MJ, 11.0, 11.6, 10.36 g protein, 10.2, 10.4, 9.64 g fat, 0, 7.37,6.72 mg -carotene per 100g, respectively. The loss of -carotene in processing and storage of curry leaf and carrot supplemented products was 13.69, 6.25 and 20.24, 8.06 percent, respectively.  相似文献   

18.
A 21-day laboratory incubation experiment was conducted to investigate the impact of pesticides (Triazophos, Butaehlor and Jinggangmycin) on a paddy field soil health under controlled moisture (flooded soil) and temperature (25℃ ) conditions. The electron transport system (ETS)/dehydrogenase activity displayed a negative correlation with pesticides concentrations, and the activity was affected adversely as the concentration of the pesticides increased. The higher doses of pesticides,5 and 10 folds field rates, significantly inhibited ETS activity, while lower rates failed to produce any significant reducing effect against the control. The relative toxicity level of pesticides in decreasing the ETS activity was in the following order:Triazophos＞Jinggangmycin＞Butachlor, irrespective of their rates of application. The pesticides caused an improvement in the soil phenol content and it increased with increasing the concentration of agrochemicals. The pesticide incorporation did not produce any significant change in soil protein content. The response of biomass phospholipid content was nearly similar to ETS activity. The phospholipid content was decreased with the addition of pesticides in the given order of Triazophos＞Jinggangmycin＞Butachlor; and the toxicity was in the order: 10 FR (times of field rate)＞5 FR＞1.0 FR＞0.5 FR＞control.  相似文献   

19.
Alpha6beta2 nicotinic acetylcholine receptors (nAChRs) are potential therapeutic targets for the treatment of several neuropsychiatric diseases, including addiction and Parkinson’s disease. Alpha-conotoxin (α-CTx) TxIB is a uniquely selective ligand, which blocks α6/α3β2β3 nAChRs only, but does not block the other subtypes. Therefore, α-CTx TxIB is a valuable therapeutic candidate peptide. Synthesizing enough α-CTx TxIB with high yield production is required for conducting wide-range testing of its potential medicinal applications. The current study optimized the cleavage of synthesized α-CTx TxIB resin-bounded peptide and folding of the cleaved linear peptide. Key parameters influencing cleavage and oxidative folding of α-CTx TxIB were examined, such as buffer, redox agents, pH, salt, co-solvent and temperature. Twelve conditions were used for cleavage optimization. Fifty-four kinds of one-step oxidative solution were used to assess their effects on each α-CTx TxIB isomers’ yield. The result indicated that co-solvent choices were particularly important. Completely oxidative folding of globular isomer was achieved when the NH4HCO3 or Tris-HCl folding buffer at 4 °C contained 40% of co-solvent DMSO, and GSH:GSSG (2:1) or GSH only with pH 8~8.7.  相似文献   

20.
Eight streptophenazines (A–H) have been identified so far as products of Streptomyces strain HB202, which was isolated from the sponge Halichondria panicea from the Baltic Sea. The variation of bioactivities based on small structural changes initiated further studies on new derivatives. Three new streptophenazines (I–K) were identified after fermentation in the present study. In addition, revised molecular structures of streptophenazines C, D, F and H are proposed. Streptophenazines G and K exhibited moderate antibacterial activity against the facultative pathogenic bacterium Staphylococcus epidermidis and against Bacillus subtilis. All tested compounds (streptophenazines G, I–K) also showed moderate activities against PDE 4B.  相似文献   

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