Impact of Pre-Anthesis Water Deficit on Yield and Yield Components in Barley (\u3ci\u3eHordeum vulgare\u3c/i\u3e L.) Plants Grown under Controlled Conditions

Drought at pre-anthesis stages can influence barley growth and results in yield losses. Therefore, it is important to understand how drought at pre-anthesis can affect different traits associated with yield reduction in barley. The objective of this study was to understand the relevance of the genetic background of major flowering time genes in barley plants subjected to pre-anthesis drought and its impact on yield and yield components. A glasshouse experiment using a Randomized Complete Block Design was conducted to investigate the effect of drought and its timing on yield and yield components on eleven barley genotypes, which were selected to represent genetic diversity of major flowering time genes (PPDH1, PPDH2, HvVrn1, HvVrn2 and HvVrn3). Barley plants were exposed to three water regimes, non-stressed and stressed, which was applied at two pre-anthesis growth stages, tillering (SS) and stem elongation (SE). Results identified differences among genotypes in all measured traits. Grain yield, grain number and thousand kernel weight were reduced in all genotypes due to drought, irrespective of the growth stage. Early flowering genotypes had better performance as reflected in higher yield compared with late flowering genotypes. Results verified the fundamental importance of early flowering to improve productivity in response to pre-anthesis drought. The results of this study can help in selecting barley lines for future breeding purposes with improved resilience to drought conditions in Mediterranean environments

Global overview of the management of acute cholecystitis during the COVID-19 pandemic (CHOLECOVID study)

There was no funding support for this study. Disclosure. The authors declare no conflict of interest.Peer reviewedPublisher PD

Global overview of the management of acute cholecystitis during the COVID-19 pandemic (CHOLECOVID study)

Background: This study provides a global overview of the management of patients with acute cholecystitis during the initial phase of the COVID-19 pandemic. Methods: CHOLECOVID is an international, multicentre, observational comparative study of patients admitted to hospital with acute cholecystitis during the COVID-19 pandemic. Data on management were collected for a 2-month study interval coincident with the WHO declaration of the SARS-CoV-2 pandemic and compared with an equivalent pre-pandemic time interval. Mediation analysis examined the influence of SARS-COV-2 infection on 30-day mortality. Results: This study collected data on 9783 patients with acute cholecystitis admitted to 247 hospitals across the world. The pandemic was associated with reduced availability of surgical workforce and operating facilities globally, a significant shift to worse severity of disease, and increased use of conservative management. There was a reduction (both absolute and proportionate) in the number of patients undergoing cholecystectomy from 3095 patients (56.2 per cent) pre-pandemic to 1998 patients (46.2 per cent) during the pandemic but there was no difference in 30-day all-cause mortality after cholecystectomy comparing the pre-pandemic interval with the pandemic (13 patients (0.4 per cent) pre-pandemic to 13 patients (0.6 per cent) pandemic; P = 0.355). In mediation analysis, an admission with acute cholecystitis during the pandemic was associated with a non-significant increased risk of death (OR 1.29, 95 per cent c.i. 0.93 to 1.79, P = 0.121). Conclusion: CHOLECOVID provides a unique overview of the treatment of patients with cholecystitis across the globe during the first months of the SARS-CoV-2 pandemic. The study highlights the need for system resilience in retention of elective surgical activity. Cholecystectomy was associated with a low risk of mortality and deferral of treatment results in an increase in avoidable morbidity that represents the non-COVID cost of this pandemic

Recovery of plant species, richness and composition in abandoned grassland in arid region

A harsh ecosystem in a semi-arid area is the target of the current study. Restoration pattern was not well understood due to the lack of studies. Botanical surveys were performed over the years 2005 through 2011 in the semi-arid area in Jordan. Our objectives were to identify the vegetative cover types and the extent of restoration. Quantitative and qualitative analysis on plant species were conducted. The potential and pattern of restoration in term of plant species richness and vegetative cover composition were measured. Results showed that 34 different plant species were found to be grown in the study area, and they belonged to 14 plant families and 4 chorotypes. Mediterranean-Irano-Turanian was the dominant. We concluded that the composition of the vegetation cover did not recover as similar to the original composition after abandonment. However, further researches are needed to precisely track the effect of abandonment on vegetative cover development and restoration

Effect of formic acid on the control of the bee parasitic mite Varroa destructor under semiarid conditions

These experiments were conducted at Jordan University of Science and Technology campus from April to November of 2004, to investigate the effect of formic acid on the infestation of honeybee colony with Varroa destructor . Formic acid was applied at concentrations of 75%, 85%, or 98% using three methods of application, above, bottom, or both ways. Results indicated that the use of formic acid at low concentration (75%) did not have obvious effect on Varroa infestation with the three methods of application. Application of 98% formic acid resulted in a negative effect on the number of brood and worker bees, although it reduced the infestation rate of the colonies with Varroa to 0%. The moderate concentration of formic acid (85%) reduced the infestation rate with Varroa to a very low level, 2–3% using the three methods of application, whereas numbers of brood and workers of honey bees were not influenced. Moderate concentration of formic acid (85%) indicated that the correlation of the three methods of applications to the percentage of infestation rate was not highly significant at p ≤ 0.05. The bottom application was the most effective in controlling Varroa mite

Impact of Pre-Anthesis Water Deficit on Yield and Yield Components in Barley (\u3ci\u3eHordeum vulgare\u3c/i\u3e L.) Plants Grown under Controlled Conditions

Drought at pre-anthesis stages can influence barley growth and results in yield losses. Therefore, it is important to understand how drought at pre-anthesis can affect different traits associated with yield reduction in barley. The objective of this study was to understand the relevance of the genetic background of major flowering time genes in barley plants subjected to pre-anthesis drought and its impact on yield and yield components. A glasshouse experiment using a Randomized Complete Block Design was conducted to investigate the effect of drought and its timing on yield and yield components on eleven barley genotypes, which were selected to represent genetic diversity of major flowering time genes (PPDH1, PPDH2, HvVrn1, HvVrn2 and HvVrn3). Barley plants were exposed to three water regimes, non-stressed and stressed, which was applied at two pre-anthesis growth stages, tillering (SS) and stem elongation (SE). Results identified differences among genotypes in all measured traits. Grain yield, grain number and thousand kernel weight were reduced in all genotypes due to drought, irrespective of the growth stage. Early flowering genotypes had better performance as reflected in higher yield compared with late flowering genotypes. Results verified the fundamental importance of early flowering to improve productivity in response to pre-anthesis drought. The results of this study can help in selecting barley lines for future breeding purposes with improved resilience to drought conditions in Mediterranean environments

The Effect of Supplemental Irrigation on Canopy Temperature Depression, Chlorophyll Content, and Water Use Efficiency in Three Wheat (Triticum aestivum L. and T. durum Desf.) Varieties Grown in Dry Regions of Jordan

One critical challenge facing the world is the need to satisfy the food requirements of the dramatically growing population. Drought stress is one of the main limiting factors in the wheat-producing regions; therefore, wheat yield stability is a major objective of wheat-breeding programs in Jordan, which experience fluctuating climatic conditions in the context of global climate change. In the current study, a two-year field experiment was conducted for exploring the effect of four different water regimes on the yield, yield components, and stability of three wheat (Triticum aestivum L.; T. durum Desf.) Jordanian cultivars as related to Canopy Temperature Depression (CTD), and Chlorophyll Content (measured by Soil-Plant Analysis Development, SPAD). A split plot design was used in this experiment with four replicates. Water treatment was applied as the main factor: with and without supplemental irrigation; 0%, 50%, 75%, and 100% of field capacity were applied. Two durum wheat cultivars and one bread wheat cultivar were split over irrigation treatments as a sub factor. In both growing seasons, supplemental irrigation showed a significant increase in grain yield compared to the rain-fed conditions. This increase in grain yield was due to the significantly positive effect of water availability on yield components. Values of CTD, SPAD, harvest index, and water use efficiency (WUE) were increased significantly with an increase in soil moisture and highly correlated with grain yield. Ammon variety produced the highest grain yield across the four water regimes used in this study. This variety was characterized by the least thermal time to maturity and the highest values of CTD and SPAD. It was concluded that Ammon had the highest stability among the cultivars tested. Furthermore, CTD and SPAD can be used as important selection parameters in breeding programs in Jordan to assist in developing high-yielding genotypes under drought and heat stress conditions

Effect of nanoTiO2 dopant on electrical properties of SR8100/nanoTiO2 PMNC

SR 8100 epoxy was doped with nTiO2​ nano filler to produce a semiconducting PMNC. The specimen made of SR8100/nanoTiO2 PMNC with nanoTiO2 content ranges from 1 to 5 wt% with 1% step prepared by hot vibrate dispersion (HVD). Morphology changes in polymer were detected by XRD and it has been found that SR8100 begins to have a crystalline nature when nanoTiO2 concentration was 3%, 4% and 5%. Electrical resistivity increases from 1*10−9 Ω m for SR8100 up to 2.3*10−4 Ω m for SR8100/5% nanoTiO2 PMNC which means that the material turns from an insulator to a semiconductor. Keywords: PMNC, Hot vibrate dispersion, Electrical properties, Ceramic oxide nano filler