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[en] Shortage of irrigation water at critical growth stages of maize is limiting its production worldwide. Breeding drought-tolerant cultivars is one possible solution while identification of potential genotypes is crucial for genetic improvement. To assess genetic variation for seedling-stage drought tolerance, we tested 40 inbred lines in a completely randomized design under glasshouse conditions. From these, two contrasting inbred lines were used to develop six basic generations (P1, P2, F1, F2, BC1F1, BC2F2). These populations were then evaluated in a triplicated factorial randomized complete block design under non-stressed and drought-stressed conditions. For statistical analyses, a nested block design was employed to ignore the replication effects. Significant differences (p=0.01) were recorded among the genotypes for investigated seedling-traits. Absolute values of fresh root length, fresh root weight, and dry root weight lead to select two genotypes, one tolerant (WFTMS) and one susceptible (Q66). Estimates of heritability, genetic advance, and genotypic correlation coefficients were higher and significant for most of the seedling-traits. Generation variance analysis revealed additive gene action. Narrow-sense heritability [F2 = 65; F8 = 79] revealed the same results. Generation mean analysis signified additive genetic effects in the inheritance of cob girth, non-additive for plant height, grains per ear row and grain yield per plant, and environmental for ear leaf area, cob length, grain rows per ear, biomass per plant, and 100-grain weight under drought-stressed conditions. For conferring drought-tolerance in maize, breeders can adopt the recombinant breeding strategy to pyramid the desirable genes. (Author)
[en] Congenital amegakaryocytic thrombocytopenia (CAMT) is a rare, autosomal recessive disorder induced by mutations of the gene coding for thrombopoietin (TPO) receptor (c-MPL) despite high levels of serum TPO. Patients initially present with isolated thrombocytopenia that subsequently progresses into pancytopenia. Although the mechanisms leading to aplasia are unknown, the age of onset has been reported to depend on the severity of the c-MPL functional defect. The primary treatment for CAMT is bone marrow transplantation. This report describes a newborn girl who presented to us with symptoms of sepsis but septic profile came negative except thrombocytopenia. Bone marrow biopsy was done for thrombocytopenia which revealed amegakaryocytic thrombocytopenia. She was given prednisolone. (author)
[en] To determine the effectiveness of Mahidol Scoring for assessing various grades of thalassemia intermedia. Study Design: Cross-sectional study. Place and Duration of Study: Fatima Memorial Hospital, Shadman, Lahore, from August 2016 to August 2017. Methodology: A total of 150 patients, both inpatient and outpatient diagnosed as thalassaemia intermedia fulfilling inclusion criteria, were enrolled, interviewed and examined after an informed consent. All patients were assessed by using Mahidol Scoring system. Their scores were documented on a predesigned evaluation porforma. Patients were labelled as mild, moderate or severe diseased. Results: In a total of 150 patients, 88 (58.7%) were males and 62 (41.3%) were females. Using Mahidol Scoring, 88 (58.7%) were labelled as mild, 53 (35.3%) as moderate and 9 (6%) as severe diseased. Patient who were labelled as mild diseased according to Mahidol Scoring, had no blood transfusions and showed good response to hydroxyurea. Patients with moderate score, were infrequently transfused and showed variable response to hydroxyurea. Patients in severe group received first transfusion at an early age, maintained lower Hb levels, showed growth retardation, splenomegaly, and had poor response to hydroxyurea. Conclusion: Mahidol Scoring system is an easy, safe and effective way for classification of thalassaemia Intermedia severity. The grades according to Mahidol Scoring system will aid in the management of patients as the score can be quickly calculated, and can assist the clinician in an initial evaluation for disease severity in patients of thalassaemia intermedia. (author)
[en] Tulip (Tulipa gesneriana L.) holds spectacular and colorful bright floral buds that are widely adorned like no other flower, across the globe. In cut flowers, persistent and prolonged display life is the matter of concern which decides quality index for florists and consumers. Endophytic bacteria, taken up by the plants when colonized, can act as sink for 1-aminocyclopropane-1-carboxylate (ACC), hence delay senescence. These bacteria, when used as suspension solution for cut flowers, increase the vase life manifolds which signify their application to commercial floriculture. Keeping in view, the exalted status and market value of cut tulips, an experiment was conducted to study the response of four bacterial strains viz. Burkholderia phytofirmans (PsJN), Caulobacter sp. (FA-13), Enterobacter sp. (MN-17) and Bacillus sp. (MN-54) along with control treatment (non-treated stems) in concentrated and diluted forms to estimate the postharvest longevity. 15 mL of suspension solution of bacterial culture was sprayed on each observational unit under controlled conditions in laboratory. In this experiment, (PsJN) in concentrated form, performed best and resulted in the longest vase life (11.2 d), delayed leaf yellowing (8.8 d), more water uptake (70.33 mL), less stem elongation (5.14 cm), more days to open flower bud (2.47 d), maximum flower diameter (50.79 mm) and . Whereas (MN-17) in concentrated form performed best in fresh and dry mass ratio and reduced stem bending. In conclusion, use of plant growth promoting bacteria (PGPB) is a useful tool in escalating vase life of cut tulips with improved floral attributes. (author)
[en] The non-LTR retrotransposons (retroposons) are abundant in plant genomes including members of Brassicaceae. Of the retroposons, long interspersed nuclear elements (LINEs) are more copious followed by short interspersed nuclear elements (SINEs) in sequenced eukaryotic genomes. The SINEs are short elements and ranged from 100-500 bps flanked by variable sized target site duplications, 5' tRNA region with polymerase III promoter, internal tRNA unrelated region, 3' LINEs derived region and a poly adenosine tail. Different computational approaches were used for the identification and characterization of SINEs, while PCR was used to detect the SINEs insertion polymorphisms in various Brassica genotypes. Ten previously unidentified families of SINEs were identified and characterized from Brassica genomes. The structural features of these SINEs were studied in detail, which showed typical SINE features displaying small sizes, target site duplications, head regions, internal regions (body) of variable sizes and a poly (A) tail at the 3' terminus. The elements from various families ranged from 206-558 bp, where BoSINE2 family displayed smallest SINE element (206 bp), while larger members belonged to BoSINE9 family (524-558 bp). The distribution and abundance of SINEs in various Brassica species and genotypes (40) at a particular site/locus were investigated by SINEs based PCR markers. Various SINE insertion polymorphisms were detected from different genotypes, where higher PCR bands amplified the SINE insertions, while lower bands amplified the pre-insertion sites (flanking regions). The analysis of Brassica SINEs copy numbers from 10 identified families revealed that around 860 and 1712 copies of SINEs were calculated from B. rapa and B. oleracea Whole-genome shotgun contigs (WGS) respectively. Analysis of insertion sites of Brassica SINEs revealed that the members from all 10 SINE families had shown an insertion preference in AT rich regions. The present analysis will be helpful in SINEs annotation in Brassica and their identification from related genera. The SINE based molecular markers will also assist to study the diversity among closely related genotypes and cultivars of various species. (author)
[en] Phosphorus (P) use efficiency is very low (5 to 25 percent) due to fixation with Ca+2/Mg+2 in alkaline/calcareous soils which decreases P availability for plant uptake. There is need to improve P availability for plant growth. For this purpose, coating of phosphatic fertilizer with the organic polymer may reduce P fixation and cause the steady release of P to increase its use efficiency. This study accesses enhanced phosphorus use efficiency along with improved growth of wheat at different rates of polymer coated di-ammonium phosphate (DAP) in comparison with uncoated DAP. In laboratory experiments, release pattern of P in soil from different coating concentrations (0, 0.5, 1.0, 1.5percent) and number of coatings (uncoated, single, double, triple) were tested under controlled conditions. The best screened polymer concentration (1percent) and coating layers (double coating) were tested under field conditions on wheat crop growth, yield and fertilizer efficiency. Results showed that application of 100percent of recommended rate of P as polymer coated DAP increased plant height (4percent), biological yield (39percent), grain yield (29percent), agronomic efficiency (58percent), recovery efficiency (130percent) and nitrogen, phosphorus and potassium contents of wheat grain and straw was also increased compared to uncoated DAP. These results revealed that polymer coated DAP can be proved more effective fertilizer to improve growth, yield and phosphorus use efficiency of the wheat crop over commercial DAP. (author)
[en] In this paper, effects of Hall currents and nonlinear radiative heat transfer in a viscous fluid passing through a semi-porous curved channel coiled in a circle of radius R are analyzed. A curvilinear coordinate system is used to develop the mathematical model of the considered problem in the form partial differential equations. Similarity solutions of the governing boundary value problems are obtained numerically using shooting method. The results are also validated with the well-known finite difference technique known as the Keller-Box method. The analysis of the involved pertinent parameters on the velocity and temperature distributions is presented through graphs and tables
[en] Optical emission spectroscopy is used to investigate the effect of neon mixing on the excitation and vibrational temperatures of the second positive system in nitrogen plasma generated by a 13.56 MHz RF generator. The excitation temperature is determined from Ne I line intensities, using Boltzmann's plot. The overpopulation of the levels of the N2 (C 3Πu, ν') states with neon mixing are monitored by measuring the emission intensities of the second positive system of nitrogen molecules. The vibrational temperature is calculated for the sequence Δν = -2, with the assumption that it follows Boltzmann's distribution. But due to overpopulation of levels, e.g. 1, 4, a linearization process was employed for such distributions allowing us to calculate the vibrational temperature of the N2 (C 3Πu, ν') state. It is found that the excitation temperature as well as the vibrational temperature of the second positive system can be raised significantly by mixing neon with nitrogen plasma. It is also found that the vibrational temperature increases with power and pressure up to 0.5 mbar.
[en] Conventional Phase Controlled Rectifier injects low order current harmonics into the AC mains. Large size filtering components are required to attenuate these harmonics. In this paper, three phase six-switch PWM buck rectifier is presented which operates at nearly unity power factor and provides variable output voltage. Small size energy storing components are required depending upon switching frequency. MATLAB simulation is performed and modified Sinusoidal Pulse Width Modulation (SPWM) switching technique is used in 3kW prototype converter to demonstrate low input current THD, nearly unity displacement factor, well regulated output voltage and reduced switching losses compared to conventional SPWM.