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1.
A comparison was made of the response to storage temperatures (0–17°C) of grapefruit ‘Shamouti’ and ‘Valencia’ oranges, and lemon fruit. There was no chilling injury (CI) and the incidence of rot was relatively low at 12°C or higher for all cultivars. At low storage temperatures, however, pitting and subsequent rot development in grapefruit and in ‘Shamouti’ and ‘Valencia’ oranges were highest at 6°C, while in lemon the incidence of these disorders rose with the decrease in storage temperature, and was highest at 2°C. Grapefruit and ‘Shamouti’ oranges exhibited the highest susceptibility to CI, lemon showed an intermediate susceptibility, and ‘Valencia’ orange a very low one. In grapefruit, severe peel pittings that developed in cold storage were covered by mold rots during cold storage and shelf-life, but in ‘Valencia’ and particularly in ‘Shamouti’ oranges the incidence of decay during cold storage was low. During shelf-life, a pronounced CI-induced increase in the incidence of mold rots was evident. This breakdown during shelf-life may be associated with microscopic peel injuries which are formed during cold storage and covered by mold rots during shelf-life. Increased susceptibility of the cultivar to CI could be correlated with an increase in ethanol content at low temperatures.  相似文献   
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Won J  Kim M  Yi YW  Kim YH  Jung N  Kim TK 《Science (New York, N.Y.)》2005,309(5731):121-125
Technologies to assess the molecular targets of biomolecules in living cells are lacking. We have developed a technology called magnetism-based interaction capture (MAGIC) that identifies molecular targets on the basis of induced movement of superparamagnetic nanoparticles inside living cells. Efficient intracellular uptake of superparamagnetic nanoparticles (coated with a small molecule of interest) was mediated by a transducible fusogenic peptide. These nanoprobes captured the small molecule's labeled target protein and were translocated in a direction specified by the magnetic field. Use of MAGIC in genome-wide expression screening identified multiple protein targets of a drug. MAGIC was also used to monitor signal-dependent modification and multiple interactions of proteins.  相似文献   
4.
For prolonged storage of lemons, the best temperature to avoid rots and physiological disorders such as internal browning and peel pitting, was 14°C; for short periods only, storage at lower temperatures, 2–8°C, did not cause damage. Physiological disorders appeared in storage earlier, the lower the storage temperatures, and in fruit picked at a less ripe stage. The general appearance of the fruit is better when stored at the lower temperature. Color development, chemical changes, weight loss, respiration rate and ethylene evolution during storage of lemons at different temperatures and stages of maturity were examined.  相似文献   
5.
The Labyrinthulomycetes or Labyrinthulea are a class of protists that produce a network of filaments that enable the cells to glide along and absorb nutrients. One of the main two Labyrinthulea groups is the thraustochytrids, which are becoming an increasingly recognised and commercially used alternate source of long-chain (LC, ≥C20) omega-3 containing oils. This study demonstrates, to our knowledge for the first time, the regiospecificity of the triacylglycerol (TAG) fraction derived from Australian thraustochytrid Aurantiochytrium sp. strain TC 20 obtained using 13C nuclear magnetic resonance spectroscopy (13C NMR) analysis. The DHA present in the TC 20 TAG fraction was determined to be concentrated in the sn-2 position, with TAG (16:0/22:6/16:0) identified as the main species present. The sn-2 preference is similar to that found in salmon and tuna oil, and differs to seal oil containing largely sn-1,3 LC-PUFA. A higher concentration of sn-2 DHA occurred in the thraustochytrid TC 20 oil compared to that of tuna oil.  相似文献   
6.
Organic wastes can be usefully recovered to produce organic amendments, for example, compost, to be used for crop production, thus reducing impacts through efficient waste management. The aim of this work was to study the effects of compost obtained from municipal waste in combination with poultry manure on plant growth, nitrate reductase (NR) activity and absorption and distribution of heavy metals (HM) in plant tissues of tomatoes, grown in pots in greenhouses. Two compost types obtained from municipal waste mixed with poultry manure (C1?=?3:2 and C2?=?2:3) were used at two different ages (105 d and 173 d) and at two mix rates with soil (32.5?g pot?1 and 65?g pot?1); soil with no compost amendment was used as control. The experiment was conducted using tomato plants in pots and plant growth and nutrient plant uptake was determined after 65?days from plant transplanting. Results obtained indicated that compost type and compost rate affected biomass production. However, compost age did not influence the development of plants. Nutrient status of tomato plants was also investigated with reference to the N cycle. Nitrite accumulation in the leaves increased with the increase in compost doses. The accumulation of NO2? was associated with a significant increase in NR activity. HM content in leaves decreased with compost use. HM accumulated preferentially in roots and leaves and the soil to root metals transfer was in this order: Fe (1.08–2.14)> Co (0.53–4.10)>Cu (0.28–2.28) >Mn (0.3–1.34) >Zn (0.87–1.21)>Cr (0.12–1.64). The highest and lowest dynamic bioaccumulation factors (BAFdyn) were observed in roots and stems, respectively. The root system acted as a barrier for Cd and Pb. It was concluded that compost use is beneficial for tomato plants, with particular reference to the compost obtained by using a higher amount of poultry manure (C2) in the mix.  相似文献   
7.
对生菜(Lactuca sativa)分别均匀喷洒浓度为70、140、280μg/L的杀虫剂氰戊菊酯,以清水为对照,以意大利全年耐抽薹生菜为试材,结果表明,随着农药浓度的增加,光系统Ⅱ的最大光化学效率、实际光化学效率、光化学淬灭系数和相对电子传递速率均下降,非光化学淬灭系数、非调节性能量耗散的量子产额和调节性能量耗散的量子产额上升,综合影响造成光系统Ⅱ的中心活性区域缩小、光合速率下降。另外生菜叶片自身的光化合保护机制能在一定程度上减轻农药的胁迫作用。与对照相比,光系统Ⅱ的实际光化学效率受农药影响最大,喷洒浓度为280μg/L的杀虫剂会对生菜光合作用过程产生持续性的、不可逆转的影响。  相似文献   
8.
The aim of this experiment was to evaluate the symptoms, variation, and correlation of hematological factors and some parameters of the innate immune response of the infected rainbow trout (Oncorhynchus mykiss) fish with Lactococcus garvieae bacteria. A total of 270 fish were divided into three groups including infected fish with a high and low concentration of L. garvieae and a control group without infection. The blood and tissue (brain, head, kidney, and spleen) samples were collected from each group (n?=?6 fish) at 0, 3, 14, and 21 days after treatment. The most observed symptoms during infection were lethargy, exophthalmia, and ascites. The mortality rates for the high and low dose-infected fish were defined as 60 and 25%, respectively. The infected groups had significantly (p?<?0.05) higher activity of serum lysozyme, myeloperoxidase, classical and alternative pathways of complement, serum bactericidal effects, and the specific antibody titer. Also, a significant (p?<?0.05) lower hematocrit and hemoglobin levels and higher white blood cell numbers were observed in the infected groups. A significant correlation was observed between the CRP levels and some of the hematological and immunological indices as bactericidal effects, classical complement pathways, lysozyme activity myeloperoxidase activity, white blood cell numbers, and hematocrit levels. The clinical symptoms, immune responses, and hematological indices variation among L. garvieae-infected fish are dependent on the duration and bacterial dose of the infection.  相似文献   
9.
Pseurotins A1 (1) and A2 (2) were isolated from a culture broth of the fungal strain Aspergillus fumigatus WFZ-25 as stereoisomers of pseurotin A (3) in 2011. We also isolated 1 and 2 together with 3 from A. fumigatus OUPS-T106B-5 separated from the marine fish Mugil cephalus. In this study, we re-examined the stereochemistry of 1 and 2 using chemical transformation and the CD spectra, and found the relationship between the CD Cotton effect and the absolute configurations of 1 and 2, which led us to revise the stereostructure of pseurotin A2.  相似文献   
10.
We observed that the growth of three Amaranthaceae species was promoted by sodium (Na), in the order dwarf glasswort (Salicornia bigelovii Torr.) >> Swiss chard (Beta Burgaris L. spp. cicla cv. Seiyou Shirokuki) > table beet (Beta vulgaris L. spp. vulgaris cv. Detroit Dark Red). In the present study, these Na-loving plants were grown in solutions containing 4 mol m?3 nitrate nitrogen (NO3-N) and 100 mol m?3 sodium chloride (NaCl) and potassium chloride (KCl) under six Na to potassium (K) ratios, 0:100, 20:80, 40:60, 60:40, 80:20 and 100:0, to elucidate the function of Na and K on specific characteristics of Na-loving plants. The growth of dwarf glasswort increased with increasing Na concentration of the shoot, and the shoot dry weight of plants grown in 100:0 Na:K was 214% that of plants grown at 0:100. In Swiss chard and table beet, growth was unchanged by the external ratio of Na to K. The water content was not changed in Swiss chard or table beet by the external Na to K ratio. These observations indicate that both Na and K have a function in osmotic regulation. However, dwarf glasswort could not maintain succulence at 0:100; therefore, Na has a specific function in dwarf glasswort for osmotic regulation to maintain a favorable water status, and the contribution of K to osmotic regulation is low. NO3-N uptake was promoted by Na uptake in dwarf glasswort and Swiss chard. NO3-N uptake and transport to shoots was optimal at 100:0 in dwarf glasswort and at 80:20 in Swiss chard. These functions are very important for the Na-loving mechanism, and the contribution of K was lower in dwarf glasswort than in Swiss chard.  相似文献   
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