Influences of day and night temperatures on flowering of Fragaria x ananassa Duch., cvs. Korona and Elsanta,at different photoperiods     

Michèl J. Verheul  Anita SønstebySvein O. Grimstad 《Scientia Horticulturae》2007

The effects of photoperiod (12, 13, 14, 15 or 16 h), day temperature (12, 15, 18, 24 or 27 °C) and night temperature (6, 9 or 12 °C) and their interactions on flower and inflorescence emergence were investigated by exposing 4 week old runner plants of strawberry cvs. Korona and Elsanta during a period of 3 weeks. A daily photoperiod of 12 or 13 h resulted in the highest number of plants with emerged flowers. A photoperiod of 14 h or more strongly reduced this number, while no flowers emerged at a photoperiod of 16 h. Plants exposed to photoperiods of 12 or 13 h flowered earlier and had longer flower trusses. A day temperature of 18 °C and/or a night temperature of 12 °C were optimal for plants to emerge flowers and resulted in the shortest time to flowering. A night temperature of 6 °C strongly reduced the number of plants that emerged flowers, especially when combined with lower day temperatures. Photoperiod and temperature had no effect on the number of inflorescences, all flowering plants produced on average one inflorescence. The number of flowers on the inflorescence increased with decreasing day temperature and when photoperiod was raised from 12 to 15 h. In general, ‘Korona’ was more sensitive to photoperiod and temperature as ‘Elsanta’, and had a lower optimal day temperature for flower emergence. Results of this experiment may be used to produce high quality plant material or to define optimal conditions when combining flower induction and fruit production.  相似文献   

Analytical method for assessing potential dermal exposure to captan, using whole body dosimetry, in small vegetable production units in Argentina   总被引：1，自引：0，他引：1  

Hughes EA  Zalts A  Ojeda JJ  Flores AP  Glass RC  Montserrat JM 《Pest management science》2006,62(9):811-818

An analytical method has been developed that can be used to determine the potential dermal exposure (PDE) of workers to the pesticide captan in small-scale horticultural production units. The methodology is based on the whole body dosimetry technique, using a cotton coverall and cotton gloves as sampling media, with protective clothing worn beneath the cotton media to protect the operator. The quantitative determination of captan was done by gas chromatography-electron capture detector (GC-ECD), with the analytical method validated by measuring limits of detection and quantification, linear ranges, sample recovery and precision. Special emphasis is placed on factors that affected the stability of captan during chromatographic determination. The data generated for potential dermal exposure are presented separately for mixing/loading and application activities. These data are compared with values obtained with visible tracers using a similar field technique. Margin of safety (MOS) values are also calculated for the agricultural procedures studied.  相似文献   

Evidence for antibody-catalyzed ozone formation in bacterial killing and inflammation     

Wentworth P  McDunn JE  Wentworth AD  Takeuchi C  Nieva J  Jones T  Bautista C  Ruedi JM  Gutierrez A  Janda KD  Babior BM  Eschenmoser A  Lerner RA 《Science (New York, N.Y.)》2002,298(5601):2195-2199

Recently, we showed that antibodies catalyze the generation of hydrogen peroxide (H2O2) from singlet molecular oxygen (1O2*) and water. Here, we show that this process can lead to efficient killing of bacteria, regardless of the antigen specificity of the antibody. H2O2 production by antibodies alone was found to be not sufficient for bacterial killing. Our studies suggested that the antibody-catalyzed water-oxidation pathway produced an additional molecular species with a chemical signature similar to that of ozone. This species is also generated during the oxidative burst of activated human neutrophils and during inflammation. These observations suggest that alternative pathways may exist for biological killing of bacteria that are mediated by potent oxidants previously unknown to biology.  相似文献   

Enzymes of Trichoderma and other origin in biopreparation of cotton          下载免费PDF全文

Anita Losonczi　 George Szakacs　 Emilia Csiszar　 Outi Kareela 《浙江大学学报(农业与生命科学版)》2004,30(4):437-437

Preparation and bleaching are among the most energy and chemical intensive steps of the traditional cotton finishing. About 75% of the organic pollutants arising from textile finishing are derived from the preparation of cotton goods. Biopreparation may be a valuable and environmentally friendly alternative to harsh alkaline chemicals for preparing of cotton. Different enzymes i.e. cellulases, pectinases, lipases and proteases have been tested for biopreparation. Many papers have been publishe…  相似文献   

Mutations in the pericentrin (PCNT) gene cause primordial dwarfism     

Rauch A  Thiel CT  Schindler D  Wick U  Crow YJ  Ekici AB  van Essen AJ  Goecke TO  Al-Gazali L  Chrzanowska KH  Zweier C  Brunner HG  Becker K  Curry CJ  Dallapiccola B  Devriendt K  Dörfler A  Kinning E  Megarbane A  Meinecke P  Semple RK  Spranger S  Toutain A  Trembath RC  Voss E  Wilson L  Hennekam R  de Zegher F  Dörr HG  Reis A 《Science (New York, N.Y.)》2008,319(5864):816-819

Fundamental processes influencing human growth can be revealed by studying extreme short stature. Using genetic linkage analysis, we find that biallelic loss-of-function mutations in the centrosomal pericentrin (PCNT) gene on chromosome 21q22.3 cause microcephalic osteodysplastic primordial dwarfism type II (MOPD II) in 25 patients. Adults with this rare inherited condition have an average height of 100 centimeters and a brain size comparable to that of a 3-month-old baby, but are of near-normal intelligence. Absence of PCNT results in disorganized mitotic spindles and missegregation of chromosomes. Mutations in related genes are known to cause primary microcephaly (MCPH1, CDK5RAP2, ASPM, and CENPJ).  相似文献   

The structure of a pH-sensing mycobacterial adenylyl cyclase holoenzyme     

Tews I  Findeisen F  Sinning I  Schultz A  Schultz JE  Linder JU 《Science (New York, N.Y.)》2005,308(5724):1020-1023

Class III adenylyl cyclases contain catalytic and regulatory domains, yet structural insight into their interactions is missing. We show that the mycobacterial adenylyl cyclase Rv1264 is rendered a pH sensor by its N-terminal domain. In the structure of the inhibited state, catalytic and regulatory domains share a large interface involving catalytic residues. In the structure of the active state, the two catalytic domains rotate by 55 degrees to form two catalytic sites at their interface. Two alpha helices serve as molecular switches. Mutagenesis is consistent with a regulatory role of the structural transition, and we suggest that the transition is regulated by pH.  相似文献   

Globalisation and income growth promote the Mediterranean diet     

Regmi A  Ballenger N  Putnam J 《Public health nutrition》2004,7(7):977-983

OBJECTIVE: To examine global food demand patterns and how changing diets may stimulate demand for and trade of Mediterranean diet products. DESIGN: Literature review. Trends in global and US food consumption patterns are examined and trade data are reviewed to evaluate the impact of changing diets on trade of Mediterranean diet products. Market access issues are also addressed briefly to highlight the role of policy in the trade of Mediterranean diet products. RESULTS: Diets are shifting towards higher-value products such as meats, fruits and vegetables, and a wider array of packaged food products. Trade in these products has also grown in the past two decades, with several non-traditional importers and exporters becoming increasingly active in the global market. CONCLUSIONS: Income-driven demands for quality and variety are likely to increase the demand for Mediterranean diet products globally. While the middle-income countries appear to be the best growth prospects, the USA remains a potential growth market if these products can meet the growing consumer demand for variety, quality and convenience. Although consumer trends globally indicate growth in demand for Mediterranean diet products, the additional demand may not be reflected by a corresponding growth in trade. Trade in Mediterranean diet products continues to be hampered by higher than average trade barriers and high transportation costs for perishables.  相似文献   

The effects of lead on algae     

Anita Hessler 《Water, air, and soil pollution》1974,3(3):371-385

The effects of lethal and sublethal concentrations of PbCl₂ on reproduction , viability, and motility of a marine unicellular green flagellate alga, Platymonas subcordiformis, were studied under controlled laboratory conditions. The severity of the effects depended primarily upon the concentration of Pb⁺⁺ and the duration of treatment. Log phase cells were more sensitive than stationary phase cells. Sublethal amounts of Pb (2.5 and 10 mg l^?1 Pb⁺⁺) tended to retard population growth by delaying cell division and daughter cell separation. A lethal amount of Pb (60 mg I^?1 Pb⁺) caused inhibition of growth and cell death. Various intracellular abnormalities resulted from Pb treatment. The flagella were shed or altered in a variety of ways, depending on Pb concentration; motility was least affected by low Pb and completely impaired by high Pb. Normal wild-type cells appeared to be more sensitive to Pb than mechanically sheared (flagella-less) cells and cells of a non-flagellate mutant of Platymonas. Exposure of cells to Pb in non-growth conditions of dark and cold (2°C) had little negative effect.  相似文献   

Ki-67/CD3 ratio in the diagnosis of chronic inflammatory enteropathy in dogs     

Sonja Karlovits  Anita Manz  Karin Allenspach  Ingrid Walter  Stefan Kummer  Alexander Tichy  Barbara Richter  Iwan A. Burgener  Nicole Luckschander-Zeller 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2020,34(1):92-97

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Antimicrobial ability and growth promoting effects of feed supplemented with probiotic bacterium isolated from gut microlfora of Cirrhinus mrigala     

Anita Bhatnagar  Ritu Lamba 《中国农业科学(英文版)》2015,(3)

The present studies were conducted to isolate, select, identify and characterize gut bacteria as antimicrobial and growth promoting agent for the feed of economical y important ifsh Cirrhinus mrigala. ...  相似文献