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Drought stress is a major production constraint in crops globally. Crop wild relatives are important sources of resistance and tolerance for both biotic and abiotic stresses, respectively. A breeding program was initiated to introgress drought tolerance in sunflowers through hybridization between the wild species Helianthus argophyllus and the cultivated pool of H. annuus. Selection was carried out from the F2 to F5 segregating populations for the silver canopy, high cuticular wax, small leaf area, single heading and high oil content. Cuticular wax ranged between 8.72 µg g−1 and 17.19 µg g−1 in the F5 offspring. The selected F5 breeding lines were self-pollinated to obtain the F6 generation. Thereafter, this F6 was compared with the non-adapted elite sunflower germplasm in a factorial complete randomized design with different water treatments; i.e., comparing fully irrigated (100%, T0) versus 75% (T1), 50% (T2) and 25% (T3) of total irrigation. The comparison between the two types of the germplasm showed that drought-tolerant breeding lines had a comparatively lesser decrease in leaf area (0, 11, 22%) and shoot length (4, 21, 28%) than the elite germplasm, which experienced a decrease in leaf area (21%, 33% and 40%) and shoot length (17, 27 and 34%) under the various drought treatments. Moreover, drought-tolerant breeding lines had 100% more root shoot ratios than the elite germplasm (20%) in T3 when compared with control. Several drought-tolerant promising lines (D-2, D-5 and D-27) were selected due to their high leaf area, great root length and increased root to shoot ratio under T3. Some of the lines could be directly used for the development of drought-tolerant hybrids. Combining ability testing indicated that D-27 (F7) was a good general combiner for seed yield plant−1 and oil content after mating with male-line RSIN.82. Resulting hybrids could help to minimize seed yield loss due to water stress and to achieve profitable cultivation of sunflowers in arid regions of Pakistan.

Hydroponic systems are known to provide a platform for uniform growth conditions until the reproductive stage. However, many plant species, including sunflower, show poor growth and survivability under conventional hydroponic systems due to poor nutrient availability, hypoxia and algal contamination. Thus, we tested various hydroponic systems to select a hydroponic system suitable for screening of sunflower germplasm. Sunflower accessions showed better growth and leaf gas exchange in newly-designed over conventional hydroponic systems. Selected hydroponic systems were further engaged in sunflower accession screening under heat and osmotic stress in a two-pan system (210 cm × 60 cm). Heat stress treatment was applied by growing sunflower germplasm at 42 °C and osmotic stress by adding polyethylene glycol 8000 which decreased the osmotic potential to − 0.6 MPa. There was significant variability among the sunflower accessions for their ability to survive under stress. Accessions such as C-2721 (43%), C-291 (46%) and D-14 (43%) had lower cell membrane injury percentage under osmotic stress and high seedling survivability (60‒80%) under heat stress when compared with susceptible accessions. Moreover, resistant accessions exhibited greater cuticular waxes and root length but lower transpiration losses. The newly designed hydroponic platform proved reliable for the selection of resistant sunflower accessions. Selected parental lines were validated by assessing their hybrids under field trials across two seasons under water and temperature stress during the reproductive phase (autumn). Hybrid H3 obtained by crossing drought and heat resistant parents had the highest seed yield and water use efficiency.

The present study is aimed at exploring different scanning parameters, detectors and their orientations for time-efficient and accurate commissioning of a 6 MV clinical linear accelerator (LINAC). Beam profiles and percentage depth dose (PDD) curves were measured with a PTW dosimetry diode, a PTW Semiflex and a PinPoint ion chamber in different orientations. To acquire beam data, equidistant (step size of 0.5 mm, 1 mm, 2 mm and 3 mm) and fanline (step size of 2-0.5 mm, 2-1 mm, 3-0.5 mm and 3-1 mm) scanning modes were employed and data measurement time was recorded. Scan time per measurement point was also varied (0.2 s, 0.5 s and 1.0 s) to investigate its effect on the accuracy and acquisition time of beam data. Accuracy of the measured data was analyzed on the basis of the variation between measured data and data modeled by a treatment planning system. Beam profiles (particularly in penumbra region) were found to be sensitive to variation in scanning resolution and showed an improved accuracy with decrease in step size, while PDD curves were affected negligibly. The accuracy of beam data obtained with the PTW dosimetry diode and the PinPoint ion chamber was higher than those obtained with the PTW Semiflex ion chamber for small fields (2 × 2 cm

Drought is a major constraint for sunflower (Helianthus annuus) production worldwide. Drought tolerance traits have been identified in the related wild species Helianthus argophyllus. This study was initiated to develop sunflower drought-tolerant genotypes by crossing cultivated sunflower with this species and analyze drought tolerance traits in the H. annuus and H. argophyllus populations, H. annuus intraspecific hybrids, and H. annuus × H. argophyllus interspecific hybrids along with the commercial hybrid Hysun-33 under three stress regimes: exogenous application of ABA, both by foliar spray and irrigation, and 5% PEG-induced osmotic stress. H. argophyllus populations had a significantly lower leaf area and higher water-use efficiency and leaf cuticular wax content under all treatments, and maintained a higher net photosynthetic rate and stomatal conductance under osmotic stress. Small leaf area and high cuticular waxes content of the wild species were, however, not inherited in interspecific hybrids which suggested for selection in F2 for these traits. Therefore, transgressive plants were selected in the F2 population to establish F3 plant progenies with silver-leafed canopy of H. argophyllus which showed higher achene yield under stress condition. These results are discussed with a view to using H. argophyllus to improve drought tolerance in cultivated sunflower.

Sunflower is an important oilseed crop, which shows susceptibility to heat stress. In this study, 63 single cross hybrids were evaluated under heat stress condition for 2 years and compared with the two commercial hybrids. Genotype and genotype × environment (GGE) was used to differentiate single cross hybrids on the basis of multiple traits. GGE biplot showed that several single cross hybrids had higher seed yield potential than standard check. Moreover, seed yield per plant (SYP) was related to pollen viability percentage, showing that achene yield was the product of high gametophytic fertility under heat stress. Hybrids having high seed yield potential under heat stress had lower cell membrane injury. GGE biplot for SYP and its components showed that single cross hybrids were characterized into two major groups. Group I was further characterized into two sub group. Group Ia included hybrids with high 100-SW, while group Ib had the hybrids with high number of seeds per head and head diameter. Gr...

Objectives Since s the clinical use of unsealed radioisotopes has been in practice and after that the radioiodine rsquo s oral administration became a gold standard for treating thyroid cancers To protect the patients rsquo family members caregivers and general public from unacceptably high radiation exposures the therapeutic dosage of I administered patients are mandatory hospitalized in special isolation room until the exposure rate at one meter meets international and national limits The current study was focused to measure the isolation duration of inpatients treated with radioiodine Material and methods The current study presents the duration of hospitalization of patients treated with I therapeutic dosages at Nuclear Institute of Medicine amp Radiotherapy NIMRA Jamshoro Pakistan from to Thirty Five patients age range from to years with cancer of thyroid administered with different activities to mCi milliCurie of I admitted in special isolated room at different times were included in this study Results The results indicated that only one of total patients discharged from hospital within first hours of I administration whereas and patients were hospitalized in isolation room for and hours after the administration of activity Eleven percent of total isolated patients n stayed for to hours at the hospital Conclusion The stay duration of I administered patients at NIMRA shows wide ranging pattern Due to rapid clearance of radioiodine form their bodies more than half of patients stayed only hours

The medical LINACS with energies greater than 8 MeV produce photo-neutrons along with x-rays. These photo-neutrons contaminate the therapeutic beam and are of concern to the personnel working around the treatment room. Consequently, study of neutron albedo is very helpful for radiation protection purposes. In this work, the integral neutron albedo is determined as a function of thickness of target materials using parallel beam of thermal neutrons for a number of materials important in radiation protection and medical purposes, including water, aluminum, lead, iron, beryllium, graphite, skin-ICRP, soft tissue-ICRP, muscle skeletal-ICRP using Geant4 Monte Carlo simulation code. These simulations clearly show that neutron albedo rises quickly with target thickness and reaches saturation after about 15 cm. The value of neutron albedo depends upon scattering material thickness and geometry of reflector and its physical properties. The results of this work have also been compared with those obtained with other experimental results and theoretical calculated values, and found a good agreement with simulated value. These calculations will be helpful for evaluating the outcome of future clinical treatment planning in LINACS, radiation protection and radiation safety. The study of these materials demonstrates that a large proportion of neutrons are reflected at the edge of reflector from 1 to 10 cm, further increasing thickness have relatively small effect on neutron-albedo.

Drought is a major constraint for sunflower (Helianthus annuus) production worldwide. Drought tolerance traits have been identified in the related wild species Helianthus argophyllus. This study was initiated to develop sunflower drought-tolerant genotypes by crossing cultivated sunflower with this species and analyze drought tolerance traits in the H. annuus and H. argophyllus populations, H. annuus intraspecific hybrids, and H. annuus × H. argophyllus interspecific hybrids along with the commercial hybrid Hysun-33 under three stress regimes: exogenous application of ABA, both by foliar spray and irrigation, and 5% PEG-induced osmotic stress. H. argophyllus populations had a significantly lower leaf area and higher water-use efficiency and leaf cuticular wax content under all treatments, and maintained a higher net photosynthetic rate and stomatal conductance under osmotic stress. Small leaf area and high cuticular waxes content of the wild species were, however, not inherited in interspecific hybrids which suggested for selection in F2 for these traits. Therefore, transgressive plants were selected in the F2 population to establish F3 plant progenies with silver-leafed canopy of H. argophyllus which showed higher achene yield under stress condition. These results are discussed with a view to using H. argophyllus to improve drought tolerance in cultivated sunflower.

Purpose/ Background: To treat the cancerous tissues the unsealed radioisotopes are being in clinical practice since 7 decades. From these unsealed sources, I-131 is the choice of treatment for the treating thyroid cancers. Orally administered I-131 patients are to be kept isolated in hospital for some period until captured activity in the body reaches to national and international limits for the avoidance of unacceptably high radiation exposures to patients' family members and the general public to keep ALARA (as low as reasonably achievable) principal in mind. The main rationale of this study was to calculate the exposure/dose of the general public. Material and Methods: This work presents the exposure rate and dose to the general public in the corridor and the non-radioactive patients admitted in adjacent room from I-131 administered isolated patients treated at NIMRA (Nuclear Institute of Medicine and Radiotherapy) Jamshoro Pakistan. In this study exposure from 23 thyroid cancer patients treated with different activities of I-131 (50 to 200 mCi) from January 2011 to December 2012 were included. Results: The average exposure rate in the corridor was about 5.17 µSv/hr (2.14 µSv/hr to 8.15 µSv/hr) and the cumulative dose to nonradioactive patients residing in an adjacent room was 0.647 mSv (0.192 mSv to 1.664 mSv). Conclusion: This study concludes that the exposure rate to the general public especially the admitted non-radioactive patient in the adjacent room is almost within the limits of 1 mSv as specified in national and international standards.-----------------------------------------Cite this article as: Memon SA, Laghari NA, Qureshi ST, Ahmad A, Khan AA, Hussain MM. Public exposure from I-131 hospitalized isolated patients in NIMRA Jamshoro Pakistan. Int J Cancer Ther Oncol 2014; 2(2):020214. DOI: 10.14319/ijcto.0202.14