Responses of wheat photosynthesis and yield to elevated CO2 under heat and water stress

Climate change involves rising CO2 and temperature, varying rainfall patterns as well as increased frequency and duration of heat stress (HS) and water stress (WS). It is important to assess the impact of climate change, including extreme events on crop productivity to manage future food security challenges. Elevated CO2 (eCO2) boosts leaf photosynthesis and plant productivity, however plant responses to eCO2 depend on environmental conditions. The response of wheat to eCO2 has been investigated in enclosures and in field studies; however, studies accounting for eCO2 interactions with HS or WS are limited. My PhD project addresses this knowledge gap. The broad aim of this thesis was to investigate the response of two commercial wheat cultivars with contrasting agronomical traits to future climate with eCO2 and more extreme events, in order to develop a mechanistic approach that can potentially be incorporated in current crop models, which, so far, fail to predict accurate yields under stressful conditions. Consequently, I investigated the interactive effects of eCO2 with either heat HS or WS on photosynthesis, crop growth and grain yield of the two wheat cultivars Scout and Yitpi grown either in the glasshouse or in a dryland field. In the first glasshouse experiment, the two cultivars were grown at current ambient (450 ppm) and future elevated (650 ppm) CO2 concentrations, 22/14oC day/night temperature, supplied with non-limiting water and nutrients and exposed to 3-day moderate HS cycles at the vegetative (38/14oC) and flowering stage (33/14oC). At aCO2, both wheat lines showed similar photosynthetic temperature responses; while larger and greater-tillering Yitpi produced slightly more grain yield than early-maturing Scout. Elevated CO2 stimulated wheat photosynthesis and reduced stomatal conductance despite causing mild photosynthetic acclimation, while moderate HS did not inhibit photosynthesis at 25oC but slightly reduced photosynthesis at 35oC in aCO2-grown plants. Elevated CO2 similarly stimulated final biomass and grain yield of the two wheat cultivars not exposed to moderate HS by variably affecting grain size and number. The main distinct outcomes of this chapter were the insignificant effect of moderate HS on wheat yield and the reduced grain nutrient quality of high tillering Yitpi at eCO2. In the second glasshouse experiment, a single cultivar Scout was grown at current ambient (419 ppm) and future elevated (654 ppm) CO2 concentrations, 22/14oC day/night temperature, supplied with non-limiting water and nutrients and exposed to 5-day severe HS cycle at the flowering stage (39/23oC). Growth at eCO2 led to downregulation of photosynthetic capacity in Scout measured at common CO2 and leaf temperature in control plants not exposed to severe HS. Severe HS reduced light saturated CO2 assimilation rates (Asat) in aCO2 but not in eCO2 grown plants. Growth stimulation by eCO2 protected plants by increasing electron transport capacity under severe HS, ultimately avoiding the damage to maximum efficiency of photosystem II. Elevated CO2 stimulated biomass and grain yield, while severe HS equally reduced grain yield at both aCO2 and eCO2 but had no effect on biomass at final harvest due to stimulated tillering. In conclusion, eCO2 protected wheat photosynthesis and biomass against severe HS damage at the flowering stage via increased maximal rate of RuBP regeneration (Jmax), indicating an important interaction between the two components of climate change, however grain yield was reduced by severe HS in both CO2 treatments due to grain abortion. The field experiment investigated the interactive effects of eCO2 and WS on two wheat cultivars Scout and Yitpi grown under dryland field conditions using free air CO2 enrichment (FACE). Plants were grown at two CO2 concentrations (400 and 550 ppm) under rainfed or irrigated conditions over two growing seasons during 2014 and 2015. Irrigation in dryland field conditions created contrasting soil water conditions under aCO2 and eCO2. Elevated CO2 and WS responses of biomass and grain yield differed in the two growing seasons. Elevated CO2 stimulated photosynthesis, biomass and grain yield, but reduced photosynthetic capacity evident from lower maximal rate of RuBP carboxylation (Vcmax) and flag leaf N only in 2015. Water stress reduced above-ground biomass and grain yield in both cultivars and CO2 treatment more strongly in 2014 relative to 2015. However, marginal growth stimulation by eCO2 did not protect plants from WS. Biomass, grain yield and grain quality were antagonistically affected by eCO2 and WS. When all data were considered together, I observed that Scout and Yitpi responded differently to growth conditions in the glasshouse and responded similarly in the field. Under well-watered conditions, Scout and Yitpi slightly benefited from moderate HS but were adversely impacted by severe HS. At the flowering stage, severe HS caused grain abortion decreasing grain yield in both CO2 treatments. Elevated CO2 alleviated photosynthetic inhibition but did not stop grain yield damage caused by severe HS. Water stress reduced net photosynthesis, biomass and grain yield in both CO2 treatments and no interaction between eCO2 and WS was observed for any of the measured parameters. Grain yield was stimulated by eCO2 more in the glasshouse than in the field. Grain nutrient quality was reduced by eCO2 and unaffected by either HS or WS (in both season average)

Extraction, purification and characterization of hyaluronic acid from Rooster comb

Hyaluronic acid, is extract by different procedures from various sources like pig, rabbit, oxes and human are available, but these processes have certain imitations like low yield, and also it requires the killing of these animals which is against the experimental ethics. In the present study, we have carried out the extraction of hyaluronic acid from cock’s comb which was further analyzed with qualitative test, viscosity, UV absorption, endotoxin detection assay. Also, the protein contamination of extracted hyaluronic acid was determined by using SDS-PAGE of hyaluronic acid was studied for checking the protein contaminants and it was noted that there were no bands observed in the well loaded with extracted hyaluronic acid sample indicating that the final extract of hyaluronic acid is not contaminated with the protein. The extraction and purification of hyaluronic acid by using the method reported here give pure hyaluronic acid. The viscosity of extracted hyaluronic acid was found to be 2.55 poise which is economical and can be used for industrial production of hyaluronic acid having clinical application

A Review on Diabetes Mellitus its Types, Pathophysiology, Epidermiology and its Global Burden

The spread of obesity and unhealthy lifestyles has contributed to a significant and increasing disease burden associated with diabetes in all countries worldwide. According to recent estimates, the worldwide prevalence of diabetes in 2013 was recorded at 382 million individuals, with projections indicating a significant increase to 592 million by the year 2035. The categorization of diabetes based on its aetiology has gained widespread acceptance in the scientific community. There are two primary classifications of diabetes, namely type 1 and type 2. Type 2 diabetes is the predominant kind, constituting a majority proportion (>85%) of the overall prevalence of diabetes. Both types of diabetes have the potential to result in a range of problems affecting several bodily systems. These complications can manifest as microvascular endpoints such as retinopathy, nephropathy, and neuropathy, as well as macrovascular endpoints including ischemic heart disease, stroke, and peripheral vascular disease. Diabetes is a significant public health concern because to its association with premature morbidity, death, diminished life expectancy, and substantial financial and societal burdens. Diabetes mellitus is a chronic metabolic illness characterised by heterogeneity and a complex pathophysiology. The condition is distinguished by increased amounts of glucose in the bloodstream, known as hyperglycemia, which arises from irregularities in either the production of insulin or the effectiveness of insulin, or both. Traditionally, diabetes has been classified into three distinct types: Type 1 DM, also known as insulin-dependent diabetes mellitus (IDDM), characterised by the body\u27s inability to make insulin, necessitating the administration of insulin by injections or the use of an insulin pump. This condition is commonly referred to as "juvenile diabetes" in medical literature. Type 2 diabetes mellitus, also known as non-insulin dependent diabetes mellitus (NIDDM), arises due to the presence of insulin resistance. This condition occurs when cells are unable to effectively utilise insulin, either with or without a complete absence of insulin. This particular classification was once denoted as "adult-onset diabetes". The third primary category is gestational diabetes, which manifests when women who do not have a prior medical history of diabetes experience elevated levels of blood glucose throughout their pregnancy. It is plausible that it may occur prior to the onset of type 2 diabetes mellitus. This article explores the various forms, pathophysiology, epidemiology, and global burden associated with the topic under discussion

Development of a novel experimental technique for the measurement of residual wall layer thickness in water-oil displacement flows

The effective removal and displacement of fluids is important in many industrial and environmental applications, such as for operation and cleaning of process equipment, fluid injection in porous media for oil recovery or aquifer remediation, or for achieving subsurface zonal isolation in new or abandoned wells. The accurate measurement of the residual fluid wall film left behind after displacement by a cleaning fluid is a long-standing challenge, particularly so for very thin fluid films where the thickness can be of the order of micrometer. We focus on the characterization of oil films left on the wall of a horizontal pipe after the pipe has been displaced by water, and develop a novel, non-intrusive analytical technique that allows the use of relevant pipe materials. The oil that originally occupies the pipe is stained by a hydrophobic dye Nile red, and an intermediate organic solvent is used to collect the residual oil volume that remains after displacing the pipe with a known volume of water. Finally, ultraviolet-visible spectroscopy is used to measure the Nile red concentration in the collected fluid, which is proportional to the residual volume of oil in the pipe. We demonstrate the methodology by conducting experiments where the displacing fluid is injected at two different imposed velocities, and where the injected fluid volume is varied. As expected, we find a gradual thinning of the oil film with increasing injected fluid volume. We compare the measured film thicknesses to a displacement model based on the steady velocity profile in a pipe, and find that experiments consistently produce smaller film thicknesses. This developed technique allows quantification of displacement and cleaning mechanisms involved in immiscible displacements at laminar, transitional and turbulent regimes, for different non-Newtonian fluid pairs, and for different realistic pipe materials and surface roughnesses.publishedVersio

Knowledge and attitude towards basics of communication skills amongst resident doctors

Background: The pillar of doctor patient relationship is the bond of mutual trust. This pillar is strengthened by effective communication between doctor and patient/relatives. It has been widely accepted that a doctor needs to have very good communication skills in addition to clinical knowledge and skills required for effective healthcare. Every doctor duly needs to demonstrate humanity, healthy behaviour, as well as sensible communication with patients which can build the sustainable ‘trust’ in the treatment offered by that doctor. However, the current curriculum of medical courses is enormously focused on providing competent medical knowledge but lacking the focus on inculcating communication skills.Methods: A cross sectional study was carried out amongst 377 resident doctors of first to third year, from randomly selected medical colleges of Maharashtra having postgraduate courses in clinical subjects and affiliated to Maharashtra University of Health Sciences, Nashik, Maharashtra, India during the period of February 2017 to January 2019. Data was entered in MS Excel sheet and analyzed using percentages and proportions wherever appropriate.Results: Highest study respondents were from General Medicine with 13% of total and having 17.4% males and 8% females among respective genders followed by General surgery and Pediatrics residents with 12.5% each specialty.Conclusions: The study has shown that there was varied knowledge about the communication skills among the resident doctors. The residents have shown fair attitudes and behaviours towards mindfulness and basic communication skills

Enhanced field emission properties of Au/SnSe nano-heterostructure: a combined experimental and theoretical investigation

We report the field emission properties of two-dimensional SnSe nanosheets (NSs) and Au/SnSe nano-heterostructure (NHS) prepared by a simple and economical route of one-pot colloidal and sputtering technique. Field Emission Scanning Electron Microscope (FESEM) analysis reveal surface protrusions and morphology modification of the SnSe NSs by Au deposition. By decorating the SnSe NSs with Au nanoparticles, significant improvement in field emission characteristics were observed. A significant reduction in the turn-on field from 2.25 V/µm for the SnSe NSs to 1.25 V/µm for the Au/SnSe NHS was observed. Emission current density of 300 µA/cm2 has been achieved at an applied field of 4.00 and 1.91 V/µm for SnSe NSs and Au/SnSe NHS, respectively. Analysis of the emission current as a function of time also demonstrated the robustness of the present Au/SnSe NHS. Consistent with the experimental data, our complementary first-principles DFT calculations predict lower work function for the Au/SnSe NHS compared to the SnSe NSs as the primary origin for improved field emission. The present study has evidently provided a rational heterostructure strategy for improving various field emission related applications via surface and electronic modifications of the nanostructures

A Comprehensive Review on Alzheimer’s Disease its Pathogenesis, Epidermiology, Diagnostics and Treatment

The global impact of Alzheimer\u27s disease (AD) is significant. The current prevalence of Major Neurocognitive Disorder is estimated to affect approximately 44 million individuals. Presently, the United States harbors a population of approximately 6.2 million individuals who are afflicted by Alzheimer\u27s disease (AD) dementia. It is of significance to highlight that mortality associated with Alzheimer\u27s disease (AD) exceeds the combined mortality rates of both breast cancer and prostate cancer. Based on the findings of the National Institute on Aging, the frequency of Alzheimer\u27s disease (AD) exhibits a twofold rise every five years subsequent to attaining the age of 65. Furthermore, with the ongoing process of population aging, an increasingly substantial portion of the population is affected by this particular condition. Based on forecasts, it is anticipated that the United States will experience a financial impact of $355 billion in 2021 as a result of Alzheimer\u27s disease (AD). Furthermore, same projections indicate that this amount is expected to increase significantly to over$1.5 trillion by the year 2050. As a result, this would place a significant financial strain on the country. Alzheimer\u27s disease (AD) is a neurodegenerative condition that is distinguished by the existence of extracellular amyloid β (Aβ) plaques and intracellular neurofibrillary tangles consisting of hyperphosphorylated τ-protein. The aforementioned abnormal characteristics primarily present themselves inside the cortical and limbic regions of the human brain. The aforementioned ailment is characterized by the presence of memory impairment and a progressive deterioration of neurocognitive abilities. The atypical division of amyloid precursor protein (APP) by β-secretases and γ-secretases leads to the production of Aβ40 and Aβ42 individual molecules, which then undergo the process of oligomerization and aggregation, finally culminating in the formation of senile plaques. The aforementioned disease is additionally aggravated by pathogenic microorganisms, including the human immunodeficiency virus (HIV). Moreover, within the framework of disease pathophysiology, the presence of heightened amounts of Aβ peptides within the central nervous system induces the infiltration of microglial cells. Presently, there exists a notable focus within the realm of scientific inquiry on gaining a comprehensive understanding of the pathological nature of Alzheimer\u27s disease (AD) by means of exploring diverse pathways. These mechanisms include the abnormal metabolism of tau proteins, the presence of β-amyloid, the inflammatory response, as well as the damage caused by cholinergic dysfunction and free radicals. The ultimate objective of this research is to develop efficacious treatments that can effectively halt or alter the progression of AD. The present study provides an analysis of the pathophysiological mechanisms underlying Alzheimer\u27s disease, as well as an examination of the diagnostic methods employed in its identification. Furthermore, the review explores the many therapy modalities now utilized in managing this neurodegenerative disorder

Inter-fragmentary compression using cannulated cancellous screws augmented with modified tension band wiring in transverse patella fractures

The classical Kirschner wires and tension band wiring technique, described by the AO foundation, has been the most widely used method for transverse patella fractures. In this study, we have adopted what we perceive to be an improved technique, the cannulated cancellous screws with modified tension band wiring. 20 patients with transverse patella fractures were included in our prospective single-blinded randomized control study with a duration of 3 years. All patients were operated on with modified tension band wiring with a 4 mm cannulated cancellous screw. Functional evaluation was made using the Tegner lysholm knee scoring scale. Roentgenograms were taken in AP and Lateral views to look for signs of radiological union and interfragmentary gap. The post-operative interfragmentary gap between fracture fragments with 65% of patients having a 0 mm gap, 25% of patients having a 1 mm gap, 5% of patients having a 2 mm gap, and 5% of patients having a 3 mm gap. The mean duration for the radiological union was 10 weeks. Mean Tegner lysholm score at 6 months was 88±4.7. We concluded that modified tension band wiring with cannulated cancellous screw is a safe, reliable, and better alternative method of fixation for transverse patella fractures with excellent union rate, range of motion, and functional outcome

Current technologies and target crops : a review on Australian protected cropping

Protected cropping offers a way to bolster food production in the face of climate change and deliver healthy food sustainably with fewer resources. However, to make this way of farming economically viable, we need to consider the status of protected cropping in the context of available technologies and corresponding target horticultural crops. This review outlines existing opportunities and challenges that must be addressed by ongoing research and innovation in this exciting but complex field in Australia. Indoor farm facilities are broadly categorised into the following three levels of technological advancement: low-, medium- and high-tech with corresponding challenges that require innovative solutions. Furthermore, limitations on indoor plant growth and protected cropping systems (e.g., high energy costs) have restricted the use of indoor agriculture to relatively few, high value crops. Hence, we need to develop new crop cultivars suitable for indoor agriculture that may differ from those required for open field production. In addition, protected cropping requires high start-up costs, expensive skilled labour, high energy consumption, and significant pest and disease management and quality control. Overall, protected cropping offers promising solutions for food security, while reducing the carbon footprint of food production. However, for indoor cropping production to have a substantial positive impact on global food security and nutritional security, the economical production of diverse crops will be essential