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111.
T F McCutchan A A Lal V F de la Cruz L H Miller W L Maloy Y Charoenvit R L Beaudoin P Guerry R Wistar S L Hoffman 《Science (New York, N.Y.)》1985,230(4732):1381-1383
Plasmodium vivax is one of the four malaria parasites that cause disease in humans. The structure of the immunodominant repeating peptide of the circumsporozoite (CS) protein of P. vivax was determined. A fragment of P. vivax DNA that encodes this tandemly repeating epitope was isolated by use of an oligonucleotide probe whose sequence is thought to be conserved in CS protein genes. DNA sequence analysis of the P. vivax clone indicates that the CS repeat is nine amino acids in length (Gly-Asp-Arg-Ala-Asp-Gly-Gln-Pro-Ala). The structure of the repeating region was confirmed with synthetic peptides and monoclonal antibodies directed against P. vivax sporozoites. This information should allow synthesis of a vaccine for P. vivax that is similar to the one being tested for P. falciparum. 相似文献
112.
Calcareous particles present in Pacific waters at depths of 50 to 3500 meters were collected by filtering seawater through spongin matrix. The specific activity of carbon-14 could be measured in two of these collections from depths of 2300 and 3500 meters. The ratios of carbon-14 to carbon-12 correspond to values observed in surface waters in recent years as a result of the addition of manmade carbon-14, thus indicating that the calcareous particles resulted from recent biological productivity. The results are related to the mean settling rates and the sizes and dissolution rates of biogenic calcareous particles in transit through a seawater column. 相似文献
113.
Investigations were undertaken to explore the possibility of improving setting, retention and weight of fruits in ‘Early Seedless’ and ‘Calcuttia’ cultivars of lichi (Litchi chinensis) by means of growth regulators. Indole acetic acid (IAA) at 20, 40 and 80 mg l?1, 2,4-dichlorophenoxy acetic acid (2,4-D) at 2,4 and 8 mg l?1 and gibberellic acid (GA3) at 50, 100 and 150 mg l?1 were sprayed on panicles in the first fortnight of April, when 50–100% flowers had opened. All 3 growth regulators caused a favourable effect on fruit setting, fruit retention and weight of individual fruits, but IAA at 20 mg l?1 proved the best for enhancing setting, GA3 at 50 mg l?1 for increasing retention and GA3 at 100 mg l?1 for improving fruit weight. IAA and GA3 should, therefore, be used in combination. Between the 2 cultivars tested, ‘Calcuttia’ proved superior to ‘Early Seedless’ in fruit setting, fruit retention and weight of individual fruits. 相似文献
114.
Mitu Ranjan Sarker;Md. Lal Chan;Mohammed Shahidul Alam; 《Fisheries Management and Ecology》2024,31(3):e12690
The marine fisheries of Bangladesh have experienced an uncontrolled expansion of fishing over the last few decades. Consequently, most fish stocks became vulnerable to overfishing. Similar to many other fisheries, catch of white sardine (Escualosa thoracata) is rapidly declining. Therefore, three data-limited approaches (length-based Bayesian biomass analysis, LBB; length-based spawning potential ratio, LB-SPR; and Froese's length-based indicators, LBIs) were used to estimate growth, mortality, and fisheries reference points to evaluate stock status of the white sardine fishery. Results revealed that the fishery is being overfished: F/M = 1.32 years−1 in LBB and 6.67 years−1 in LB-SPR. However, the stock biomass is still good with B/B0 = 0.43 and B/BMSY = 1.20. Stock indicators revealed that the fishery was mainly targeting mature fishes, most of which were mega-spawners (older, larger fish), which suggested stocks were recruitment overfished. Harvesting an optimum size range (6.57 to 8.03 cm) and reducing fishing mortality to a sustainable level (F = M) would sustain a healthy stock biomass. 相似文献
115.
Polley Shamik De Sachinandan Brahma Biswajit Mukherjee Ayan P.V. Vinesh Batabyal Subhasis Arora Jaspreet Singh Pan Subhransu Samanta Ashis Kumar Datta Tirtha Kumar Goswami Surender Lal 《Tropical animal health and production》2010,42(5):985-993
Tropical Animal Health and Production - Mutation studies in different prolific sheep breeds have shown that the transforming growth factor beta super family ligands viz. the growth differentiation... 相似文献
117.
118.
O. P. Lal 《Journal of pest science》1977,50(2):28-29
Hibernation of the beetles, Altica caerulescens Baly and Macrima armata Baly in the Kula Valley, Himachal Pradesh
The flea beetle,Altica caerulescens Baly, is a pest of bringjal, tomato, spinach, strawberry and the weedsRumex sp. andImpatiens sp. in India. The beetle,Macrima armata Baly attacks the trees ofAlnus nitida and is also found as a minor pest of radish in Kulu Valley. Both of the beetles are found only in summer. Concerning the overwintering formerly it was supposed thatA. caerulescens hibernates in pupal stage. The autor describes for the first time about the overwintering of the two species in Kulu Valley based on a survey conducted in 1972 to 1975.
Altica caerulescens hibernates in adult stage under the bark of willow (Salix alba).Macrima armata adults were found in the winter in cracks of Kosh trees (Alnus nitida). 相似文献
119.
To compare the effect of methods (foliar and soil) and rate of application of zinc sulphate on zinc and phosphorus uptake, tree size, yield and fruit quality of mango (Mangifera indica L.) cv. Dusheri, zinc sulphate was applied as a foliar spray application (0.25, 0.50, 1.0%) and soil (0.5, 1.0, 2.0 kg tree‐1) treatments during the second week of October (during flower bud differentiation period). All the zinc sulphate treatments of soil and foliar spray were effective in increasing the leaf zinc concentrations above recommended adequate level of (>20 mg kg‐1) whereas control trees maintained low leaf zinc concentrations (13.8 to 13.3 mg kg‐1). The uptake of foliar‐applied zinc was more rapid than that of soil applied zinc. All the treatments of zinc sulphate except the foliar spray treatment of zinc sulphate (0.25%) significantly increased zinc concentrations in the fruit pulp as compared with those in the control trees. The percent increase in the stem girth of trees was highest with the soil application of zinc sulphate (0.5 kg tree1) followed by foliar application of zinc sulphate (1.0%) as compared with all other treatments. The percent increase in the tree canopy volume was highest with the foliar application of zinc sulphate (1.0%) followed by soil application of zinc sulphate (1.0 kg tree1) as compared with control and all other treatments. There was no significant (P<0.05) increase in yield, fruit size and weight, pulp or stone weight with any treatment of zinc sulphate. Total soluble solid (TSS) in the fruit was significantly higher (18.6%) with the treatment of soil application of zinc sulphate (0.5 kg tree1) as compared with all other treatments of zinc sulphate and the control. Acid and sugar content of the fruit was not significantly affected by the foliar or soil application of zinc sulphate. 相似文献
120.
Physical degradation of the soil increases its susceptibility to erosion by water action. However, relatively few studies have evaluated the opposite, i.e., the impact of water erosion on soil erodibility. This study was conducted in a corn field in Ohio. Some sites within the field have experienced water-induced soil erosion following heavy rainstorms. Physical characteristics of the soil were compared between eroded (ER) and un-eroded sites (UN). Compared with ER, the soil in UN had lower penetration resistance (4.87 vs. 4.53 MPa), bulk density (1.45 vs. 1.33 Mg m?3), and sand content (17.4 vs. 14.2%), and higher shear strength (80.1 vs. 125.3 KPa), hydraulic conductivity (3.0 vs. 3.4 cm h?1), intrinsic permeability (31.9 vs. 36.4 × 10?10 cm2), and contents of soil organic carbon (36.1 vs. 32.1 g kg?1), total nitrogen (3.3 vs. 3.1 g kg?1), clay (25.2 vs. 24.2%), silt (60.5 vs. 58.4%), and very fine sand (3.4 vs. 1.1%). Also Munsell's variables differed between ER and UN (1.24 vs. 0.54 for hue, 4.59 vs. 4.35 for value, and 1.99 vs. 1.79 for chroma, respectively). The erodibility factor (K) was lower in UN than in ER (0.00327 vs. 0.00354 Mg ha h ha?1 MJ?1 mm?1, respectively). Hence, it is suggested the ER sites within the corn field agroecosystem are more susceptible to accelerated erosion as compared with UN sites. 相似文献