487 research outputs found
Response of combined abiotic stresses on maize (Zea mays L.) inbred lines and interaction among various stresses
In tropics, maize is largely grown as rain fed crop in marginal areas often faces drought and waterlogging simultaneouslyin same season that critically affects plant growth and development. The aim of the research was to studythe response of combined abiotic stresses and the interaction among various stresses on maize inbred plants. Inthe present study, eighty maize (Zea mays L.) inbred lines were screened, for multiple abiotic stresses at the vegetativestage. All the traits, observed were severely affected, in drought x low-N stress compare to waterloggingx low-N stress. However in both the stress combinations (drought x low-N and waterlogging x low-N) chlorophyllcontent decreases significantly, low-N stress has synergistic effect on the maize plants. Hence the overall effectof stress combination was negative causing enhanced damage to plants. Whereas, interaction of drought x waterloggingstress showed the antagonized each other response that primarily enhanced growth parameters (leafarea, plant height and stem diameter) and it has improved the tolerant mechanism of maize plants. Therefore weconcluded, the response of maize various plants exposed to combinations of stresses is depend on interactionof stresses
Plant defense mechanism in combined stresses - cellular and molecular perspective
The various abiotic stresses negatively influence the growth and development of plants. However, recent predictions of global climate change models have amplified the chances that plants will encounter new and more combinations of abiotic and biotic stresses. The plants adopt different strategies in combined stresses as compared to a single stress. This stress combination can be antagonist or synergistic depending on the interaction of stresses. Plants are sessile, to resists these stresses they activate defense mechanism which are complex cellular and molecular responses under combined stress conditions. At the cellular level, various kinds of biomolecules are produced that have positive and negative effects against stresses. The basic cellular process generates more reactive oxygen species (ROS) in stress conditions and causes extensive damage and inhibition of photosynthesis. Various plant hormones are involved in cellular activations to adapt the plants under stressful conditions. Further, to overcome the adverse effects of stress, the plant activates several molecular cascade mechanisms involving kinases, transcription factors, micro-RNAs, heat shock proteins, epigenetic changes. Besides, plants developed a robust signal perception and transduction mechanism to cope effectively with unfavorable conditions. Phytohormone plays a crucial role in signaling that is activated in response to combined stress conditions and in individual stress which are activated in response to abiotic and biotic stress combinations. Besides, ROS is also involved in signaling. They control a broad range of biological processes and have a conserved signaling network. Therefore, the crosstalk between different signaling pathways activates defense mechanisms and helps in the survival of plants from the various combined abiotic and biotic stress conditions
Comparison of transgenic plant production for bacterial blight resistance in Pakistani local rice (Oryza sativa L.) cultivars
The study was carried out to improve bacterial leaf blight resistance in three rice cultivars (Basmati - 370, DR - 82 and IR - 6) by Agrobacterium mediated transformation system. Three week-old scutellum derived calli were infected with Agrobacterium strain EHA101, containing binary vector pTCL5 which has Xa 21 gene. Different levels of acetosyringone were tested to enhance transformation efficiency. Acetosyringone at 300 ìM showed 56.6% GUS expression with 100 and 200 ìM acetosyringone showing 13.3 and 30.0% GUS expression, respectively. Maximum transformation efficiency was obtained using DR - 82 with calli exposed to 300 ìM acetosyringone for 2 min. Direct hygromycin selection with 48 h ofco-cultivation was superior to pre-selection in all three cultivars. Transient GUS expression was 51.4% while stable GUS expression in calli was 18.8%. PCR analysis confirmed the presence of the Xa 21 gene in transformed regenerated plants. Stable varietal transformation efficiency was DR - 82 > Basmati-370 > IR - 6. Resistance of transgenic plants against Xanthomonas oryzae pathovar oryzae was evaluated with various strains/isolates at the seedling stage. All PCR positive transgenic plants of DR - 82 and Basmati - 370 were resistant with lesion areas less than 5% of the inoculated leaf area. The tested transgenic plants were resistant to all the indigenous and exotic strains tested due to the broad spectrum protection provided by the Xa 21 gene
Outcomes of Vascular Intervention in Diabetic Patients with Peripheral Arterial Disease
BACKGROUND: Peripheral arterial disease (PAD) is more prevalent and often presents as more severe in patients with diabetes mellitus (DM) compared with those without DM. Although some patients may be asymptomatic, symptoms ranging from exertional leg heaviness and fatigue to acute limb loss are possible. PAD has significant physical and psychiatric health consequences, thus management with medical therapy and lifestyle changes are indicated. However, peripheral vascular intervention (PVI) is an increasingly popular method used in patients failing conservative management. The association of PVI with health status in diabetic patients has yet to be determined.
METHODS: We analyzed the clinical response to PVI in DM (n=203, 52%) compared with non-DM patients (n=183, 48%), using the Peripheral Arterial Questionnaire (PAQ) for patients during baseline and a maximum 6 months after PVI. 502 patients participated with an exclusion of 116 patients from our analysis due to progression of acute limb ischemia and incomplete data collection. Our finalized study population comprised 386 consecutive patients with symptomatic PAD who had also received PVI treatment during the aforementioned time frame. Our patient population received PVI treatment in the year 2012 at the St. John Hospital and Medical Center in Detroit, MI. We used the PAQ summary score, which summarizes the patients’ level of physical and social function, patient symptoms, and overall quality of life before and after the procedure. This represented the PAD-related Quality of Health (QOH). Our score range is between 0 (lowest health quality) and 100 (highest health quality).
RESULTS: Compared with non-DM patients, those with DM were more likely to have a history of prior PVI, an increased prevalence of PAD risk factors, and significantly lower QOH scores at baseline (32.7 +/- 20 vs 37.5 +/- 20.6, p=0.02). After adjustment for baseline confounding, neither the baseline, the change, nor the final summary scores were significantly different between groups. This suggests similar symptomatic and functional improvement in non-DM and DM patients post-PVI.
CONCLUSIONS: Following PVI, PAD-specific health status showed a similar improvement in patients with and without DM, illustrating that use of this strategy among patients with multiple comorbidities or diffuse PAD as useful.
Key Words: peripheral arterial disease, peripheral vascular intervention, diabetes mellitus, quality of life
Figure or Table:
Table 5. Comparison of the Summary Score of 6 PAQ Domains Using Median Scores from Mann Whitney U Test of DM and Non-DM Patients in Detroit, MI, USA
PAQ domain
DM
Non-DM
P-Value
Physical limitation
16.6 (75.4)
25.0 (79.8)
0.06
Symptoms
23.6 (75.4)
27.7 (79.8)
0.24
Symptom stability
25.0 (75.4)
25.0 (79.8)
0.28
Social limitation
16.6 (75.4)
25.0 (79.8)
0.07
Treatment satisfaction
0.0 (75.4)
0.0 (79.8)
0.42
Quality of life
16.6 (75.4)
25.0 (79.8)
0.06
Summary score
18.7 (75.4)
26.0 (79.8)
0.049
 
Design and Development of Smart Irrigation and Water Management System for Conventional Farming
The intention of this project is to develop a smart irrigation and water management system for conventional farming. The project is conducted mainly to improve the irrigation scheduling and also to solve the over watering and under watering issues in traditional irrigation system. These problems can be solved by implementing soil moisture sensor as a smart component in the irrigation system. Smart irrigation system with the implementation of sensory-based system will be able to provide a proper irrigation scheduling, by monitoring the soil and weather condition of the farm. In this project, the sensory system consists of soil moisture sensor, temperature sensor and light intensity sensor, which basically used to monitor soil moisture level, temperature level, and light intensity level at the separate test area. Arduino Mega 2560 microcontroller will process the data from these sensors and a proper irrigation scheduling will be developed based on the data collected. Type of irrigation system that been used in this project is a sprinkler system because it has high uniformity of water distribution to the plant, which able to spread water efficiency and further optimize the water usage during irrigation process. Ultrasonic sensor is also implemented in the system to measure the amount of water used in each irrigation process performed. An offline data storage will be implemented in this project using a micro SD card module, which all the essential information such as sensory system readings and the amount of water used will be recorded and stored into a micro SD card. Thus, it allows user to monitor their farm's condition, and also gives a better view on what is really happening at their farm
Effect of second order signal-noise interactions in nonlinearity compensated optical transmission systems
In this Letter, we theoretically and numerically analyze the performance of coherent optical transmission systems that deploy inline or transceiver based nonlinearity compensation techniques. For systems where signal-signal nonlinear interactions are fully compensated, we find that beyond the performance peak the signal-to-noise ratio degradation has a slope of 3 dBSNR/dBPower suggesting a quartic rather than quadratic dependence on signal power. This is directly related to the fact that signals in a given span will interact not only with linear amplified spontaneous emission noise, but also with the nonlinear four-wave mixing products generated from signal-noise interaction in previous (hitherto) uncompensated spans. The performance of optical systems employing different nonlinearity compensation schemes were numerically simulated and compared against analytical predictions, showing a good agreement within a 0.4 dB margin of error
Nonsense Mutation Inside Anthocyanidin Synthase Gene Controls Pigmentation in Yellow Raspberry (Rubus idaeus L.)
Rafique MZ, Carvalho E, Stracke R, et al. Nonsense Mutation Inside Anthocyanidin Synthase Gene Controls Pigmentation in Yellow Raspberry (Rubus idaeus L.). Frontiers in Plant Science. 2016;7: 1892
Synthesis and characterization Al2O3-ZrO2 bio-nanostructures with sintering effect, residual and thermally stable analysis
The thermal stability of nano composite materials is the important aspect of the modern era. In the advance modern devices, the nanostructures and nano composite material are used for the biological and other applications. The aluminum oxide is the most prominent oxides and composite at nano scale that show different structures, electrical and thermal properties which make it useful in different applications. Sol-Gel technique was used for synthesis to grow these nanostructures of Al2O3-ZrO2. Thermal stability was achieved and thermo-gravimetric (TGA) graphical analysis of synthesized material was performed. Size, phase and structure validation about the productive material was studied by X-Ray diffraction powder technique. Reaction completion and idea about annealing temperature of the synthesized material had pointed out by DSC-TGA (SDT) graphical peaks. Effect of the temperatures with equal variation from 5000C, 7000C, 9000C and 11000C was performed to achieve the target thermal stability. Thermal analysis was also conducted in ANSYS workbench to visualize the thermal distributes like heat flux through the material. Optical properties such as band gap variation with temperature were studied by UV-vis analysis. Fourier transform infrared (FTIR) analysis was also performed. This work provides useful information related to nanostructures with sintering effect, residual and thermally stable analysis
Use of smokeless tobacco among groups of Pakistani medical students – a cross sectional study
<p>Abstract</p> <p>Background</p> <p>Use of smokeless tobacco is common in South Asia. Tobacco is a major preventable cause of morbidity and mortality. Doctors make one of the best avenues to influence patients' tobacco use. However, medical students addicted to tobacco are likely to retain this habit as physicians and are unlikely to counsel patients against using tobacco. With this background, this study was conducted with the objective of determining the prevalence of smokeless tobacco among Pakistani medical students.</p> <p>Methods</p> <p>A cross sectional study was carried out in three medical colleges of Pakistan – one from the north and two from the southern region. 1025 students selected by convenient sampling completed a peer reviewed, pre-tested, self-administered questionnaire. Questions were asked regarding lifetime use (at least once or twice in their life), current use (at least once is the last 30 days), and established use (more than 100 times in their life) of smokeless tobacco. Chi square and logistic regression analyses were used.</p> <p>Results</p> <p>Two hundred and twenty (21.5%) students had used tobacco in some form (smoked or smokeless) in their lifetime. Sixty six (6.4%) students were lifetime users of smokeless tobacco. Thirteen (1.3%) were daily users while 18 (1.8%) fulfilled the criterion for established users. Niswar was the most commonly used form of smokeless tobacco followed by paan and nass. Most naswar users belonged to NWFP while most paan users studied in Karachi. On univariate analysis, lifetime use of smokeless tobacco showed significant associations with the use of cigarettes, student gender (M > F), student residence (boarders > day scholars) and location of the College (NWFP > Karachi). Multivariate analysis showed independent association of lifetime use of smokeless tobacco with concomitant cigarette smoking, student gender and location of the medical college.</p> <p>Conclusion</p> <p>The use of smokeless tobacco among medical students cannot be ignored. The governments should add the goal of eliminating smokeless tobacco to existing drives against cigarette smoking. Drives in Karachi should focus more on eliminating paan usage while those in NWFP should focus more on the use of naswar. Medical colleges should provide greater education about the myths and hazards of smokeless tobacco.</p
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