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[en] A severe abiotic and biotic stress was faced to cotton growers in South Punjab due to high temperature and high rain fall occurred during 2014. In current study, variation in the Cry1Ac gene expression from samples collected from five Bt (IUB-212, CIM 616, CIM-598, Lalazar, FH-183 containing Cry1Ac insecticidal gene) and one non Bt cotton (MNH 786) cultivars cultivated in three districts (Multan, Bahawalpur and Rahim Yar khan) of Southern Punjab were investigated. The investigated varieties were also cultivated under optimal greenhouses controlled conditions for expression analysis of Cry1Ac. The samples were taken to IGCDB laboratory for Cry1Ac gene expression analysis through quantitative RT-PCR and ELISA. The results indicated the abrupt variation in the expression of cry 1Ac gene in samples collected from environmental stressed districts of Punjab. Combined stress of high temperature and humidity variation resulted the down-regulation of Bt protein expression as compared to control greenhouse grown plants. The Bt cotton control efficacy was considerably reduced due to combined stress. It was concluded that reduced expression of Cry1Ac during 2014 was due to adverse environmental condition attributed to the degenerated levels of Bt endotoxin protein. This is the first report of the influence of abiotic stresses on the expressional variation in cry 1Ac and ultimately high infestation of insect pest on cotton in Pakistan. (author)
[en] Embedded components are one of the current trends in electronics, allowing to produce more compact devices with increased functionality. Such components can be applied, among others, in fabrication devices used in the Internet-of-Things technology or in special industries. Therefore, their reliability plays a key role due to safety requirements and high deployment costs. Herein, the thermal reliability of a system of sensors embedded into a printed circuit board (PCB) is examined. The samples produced are exposed to temperature cycling, -40 °C/+105 °C, or high temperature/high humidity, 85 °C/85% relative humidity (RH). The quality of solder joints is evaluated on the basis of X-ray inspection and cross sections before and after the exposure mentioned earlier. The tests show no damage to the solder joints of the samples subjected to reliability testing in high-temperature/high-humidity conditions, irrespective of the solder alloy used. Cracks appear after 500 cycles, -40 °C/+105 °C, in samples soldered with Sn99Cu1 and after 1000 temperature cycles in both Sn99Cu1 and LFM-48S (SnAg3.0Cu0.5) solders. The presented results are used for efficient embedding of electronic components into PCBs. Consequently, more space is gained for other components and the size of the electronic products is minimized. (© 2020 Wiley‐VCH GmbH)
[en] Background The goal of the current in vitro study was to assess the dimensional accuracy of dental impressions when stored at different times, temperature and humidity. Methods: Impressions were poured to an aluminium triangular die and three teeth placed at the three corners of the die. A total of 130 impressions were made, in which 10 were poured immediately following manufacturers’ instructions and the remaining 120 specimens were divided into two groups on the basis of relative humidity during storage. Group-1: 100%, Group-2: 50% relative humidity. Impression was poured with type IV gypsum. The below points were chosen to determine the length between in each of the specimens using the traveling microscope with 10x magnifications after 24 hours of model recovery for calculating the effect of changes in storage conditions- relative humidity, temperature and delay in pouring the impressions, on dimensional accuracy. Results: Analysis of the results revealed that the casts achieved by pouring alginate impressions without delay were most accurate than the delay pouring. With the increase in temperature and time, the distance between the points increased and the casts obtained were bigger. Conclusion: Irreversible hydrocolloids should be poured immediately for optimum dimensional stability. (author)
[en] The yellow tortrix, Acleris fimbriana Merick (Lepidoptera: Tortricidae), is a serious pest on fruit trees in North China. Under laboratory conditions (temperature 25 ± 1ºC, 80 ± 5% relative humidity, photoperiod 14L:10D), the effect of the 4 host plants Armeniaca vulgaris (apricot), Malus pumila (apple), Prunus salicina (plum), and Amygdalus persica (peach) on the growth, development, survival, reproduction, and life table parameters of A. fimbriana were studied. Different host plants had significant effects on the growth, development, and reproduction of A. fimbriana. The overall developmental duration was the longest on apple (60.71 d) and peach (60.78 d) and shortest on apricot (54.55 ± 3.56 d). The cumulative survival rate was highest on apricot (64.58%) and plum (60.44%) and lowest on peach (44.50%). The average number of eggs produced was highest on apricot (175.58 eggs) and plum (178.43 eggs). Life table parameter results showed that the net reproductive rate, intrinsic growth rate, and finite growth rate were highest on apricot (101.75, 0.0892, and 1.0933, respectively) and plum (97.75, 0.0832, and 1.0867, respectively). Mean generation time was the longest on apple (58.41 d) and peach (58.45 d). Population doubling time was shortest on apricot (7.77 d) and plum (8.33 d). Of the 4 hosts, apricot and peach are more suitable for A. fimbriana growth, development, and reproduction. The results of this study provide an important basis for forecasting and integrated management of A. fimbriana. (author)
[en] Oxygen-18 (18O) of plant tissues can provide information on the environmental conditions in which plants grow, because of its relation to stomatal conductance. Therefore, 18O signatures can also be related to plant stress. In future experiments, 18O will be used to assess whether fertilizer application or variety selection influences the reaction of plants to drought stress. In order to understand the dynamics of 18O isotopes in growing plants, it is necessary to know the isotopic signature of the water on which they are growing. This source water largely influences signatures which can be found in plant tissues. However, to analyze soil water, the first step is its extraction from the soil substrate. A popular way to extract soil water is cryogenic distillation. Here, soil water is almost completely extracted from the soil. However, plant roots are not able to extract all water from the soil with decreasing soil water contents. A method which samples water that resembles the water accessible for roots is centrifugation.
[en] The COVID-19 pandemic has affected all of us, as well as hampered ongoing research. This was also the case for the PUI (Peaceful Uses Initiative) project on Enhancing climate change adaptation and disease resilience in bananacoffee cropping systems in East Africa (started in 2019). Planned research activities in Tanzania had to be called off. Fortunately though, KU Leuven (Belgium), partner in this research, allowed us to initiate last-minute research activities in Belgium, turning this drawback into an opportunity. KU Leuven hosts the world’s largest banana gene bank and has proven experience and knowhow on assessing drought stress in banana. Against this background, an experiment was set up in an open-ground greenhouse, in cooperation with MSc student. The purpose was to (1) evaluate different stress parameters and measurement methods under progressing drought conditions and (2) improve our understanding of the δ13C signal as a proxy for water use efficiency in banana. An optimal and a deficit irrigation treatment were applied to nine mature banana plants (cv. Cavendish). Treatments were initiated at the end of June 2020. The soil moisture availability was followed up with TDR sensors for every individual plant and the micro-environment (air temperature (°C), relative humidity (%) and light intensity (μmol (m²s)-1) was monitored with strategically placed sensors.
[en] This study aims to: (1) Acquire the radon level in closed office rooms, providing radon exposure data for preliminary health risk assessment of office-working population. (2) Pre-analyze the relationship between radon concentration and indoor temperature, relative humidity. (3) Estimate seasonal, annual and total radon effective dose for ordinary office-working population. The results show that the 24-h or 8-h average radon concentrations in closed office rooms were about 32.0 Bq/m3 and 29.5 Bq/m3 during detection period, and the estimated effective doses in office rooms calculated by using 24-h and 8-h average radon concentrations were all far below that in residential environment. (author)
[en] Fifteen genotypes of spring wheat (Triticum aestivum L.) including eleven commercial cultivars, three landraces, and one Mexican variety were evaluated in an entirely different mega-environment with harsh natural stress. The plants experienced a hot and humid climate during the vegetative and reproductive stages. Three different sowing dates one-month apart were employed to all the genotypes to experience, in replications, three different regimes of harsh environmental conditions that would allow all the developmental and reproductive stages to experience high-temperature stress. It was hypothesized that all the genotypes do not have the same strategy to cope with the conditions and some must do better than others though none of them had been developed for this typical climate. Though all the genotypes were adversely affected due to delayed sowings, few showed some stability in the yield and yield components whereas others managed their green leaf status for a relatively longer duration. It has been learned that spring wheat has adaptive potential to be cultivated in warm-dry tropical weather with irrigation and certain genotypes may be used for a breeding program of wheat with abiotic stress tolerance for such geographical zone. (author)
[en] Materials such as magnesium phosphate cement (MPC) have attracted significant attention of researchers, therefore, understanding the effects of dosage parameters, such as water content and MgO/ NH4H2PO4 ratio on phase formation is essential for obtaining cementitious matrices with improved performance. In the present work MgO was sintered at 900 °C and 1110 °C in a conventional oven, and the effect of water concentration and MgO/NH4H2PO4 (or ADP) ratio on the properties of MPC was evaluated in terms of phase formation by X-ray diffraction, pore size distribution, mechanical properties, and microstructure. For less-reactive MgO (calcined at 1100 °C) with a high MgO/ADP ratio, increased water content did not cause additional solubilization of ADP or formation of more hydrated phases, although the cement porosity increased. Compositions with more reactive MgO (calcined up to 900 °C) formed dittmarite (NH4MgPO4.H2O) independent of water content. Higher water content and MgO calcination temperature were associated with increased MPC setting time and decreased mechanical strength due to higher porosity. (author)
[en] The complexity in earthquake occurrences has forced scientists to adopt an interdisciplinary approach for the development short-term forecasting model. In this manuscript, the authors have presented an interdisciplinary scheme involving pre-earthquake signals like geo-electrical measurements, relative humidity (RH) and outgoing longwave radiation (OLR). Prior to the occurrence of earthquakes, these parameters show exceptional deviation and indicate the nucleation of the earthquakes at the seismically active zones. Variations in the geo-electrical potential are observed prior to the occurrence of the earthquakes due to the physical and chemical interactions between hydrogen and Earth’s interior, which in turn facilitates the migration of the H+ ions through the interior of the earth. Also, this migration process weakens lithosphere, which produces non-synchronous stress variations along the fault interface. Due to the increased stress, the radioactive radon comes out from the voids of the rocks, ionizes the atmospheric air, which leads to the release of latent heat, and can be observed in the form of anomalous drop in RH and rise in OLR. Prior to the occurrence of Central Italy region earthquakes of the year 2016 (M > 6.0), the above-mentioned parameters have shown a significant variation than ± 2σ level. (author)