Waste management of solar cells in South Asia: an environmental concern of the emerging market.

The share of solar energy in the energy mix has become a major concern, and the global effort is to increase its contribution. Photovoltaic technology is an environment-friendly way of electricity production compared to fossil fuels. Currently, third generation of solar cells with a maximum average conversion efficiency of 20% has been achieved. Asia is an emerging market for photovoltaic technology, and it has recorded the highest installation capacity for 2018 (280 MW), 2030 (1860 MW), and 2050 (4837 MW). Meanwhile, Asia is estimated to be the highest producer of PV waste by 2040, with 5,580,000 metric tons of waste volume. Solid waste management is already a big environmental issue in South Asian countries, and untested landfilling of solar cells can further increase the burden. This review emphasizes the end-of-life scenario of solar cells in developing South Asian countries. Solar cell waste is hazardous e-waste that can lead to environmental and health impacts if not managed properly. It consists of metals with market value, which can be waste or gold, depending on its management. The study finds that recycling is the economically and environmentally effective waste management option for solar cells in South Asia. This paper reviews the deficiencies in the existing solar cell waste management framework in South Asian countries. Moreover, practical implications are presented for designing an effective waste management plan for solar cells in South Asian countries. Strong legislation, sufficient recycling infrastructure, and high stakeholders' interests are required to resolve this environmental concern.

Evaluation of Pakistani wheat germplasm for leaf rust resistance at various locations.

341 entries comprising of 250 genotypes/lines and 91 gene differentials were tested for leaf rust (Puccinia triticina Erik) in different ecological zones of Punjab during 2016-17 and 2017-18. Each entry was planted in a single 1 m long row and Morocco was used as a spreader. Data on leaf rust severity was recorded once in 3rd week of March during both study years at all locations by following Modified Cobb Scale while the data was recorded three times on 2nd, 22nd and 29th March during 2018 at Faisalabad location to study rust development pattern. The disease severity ranged from 0-100S during 2016-17 and from 0-80S during 2017-18. The genotype HYT 60-5 and the genes Lr-19, Lr-26 and Lr 27+31 showed no disease symptoms at any location during both the study years. These genes can be used for future breeding material development. Area under disease progressive curve (AUDPC), calculated on the basis of periodical readings from Faisalabad, ranged from 0-550 and the susceptible check Morocco has AUDPC value of 600. 120 entries including HYT 60-5 have disease progression 0, which showed that there may be a major gene based resistance in these entries. Area under disease progressive curve/Day (AUDPC/DAY) was calculated for the rest of 130 genotypes to have an understanding of the disease progression pattern and out of which 43 entries have AUDPC/Day value ranging from 1-2 and 28 entries have AUDPC/Day value ranging from 2-3 which revealed that these entries are very useful for use in breeding for durable rust resistance and can be utilized as a parent in back cross and top cross breeding schemes. Material with AUDPC value less than 10 is the best source of resistance against the leaf rust. Varieties/advanced lines, Ujala-16, V-14154, and V-14124 have shown slow rust development and are very good sources of resistance. Similarly, HYT 60-5 has proven an excellent source of resistance. The advance line V-14154 has been approved as a commercial cultivar by the name "Akbar-19".

Knowledge, attitude, and practice of artificial intelligence among doctors and medical students in Pakistan: A cross-sectional online survey.

Background: The use of Artificial intelligence (AI) has gained popularity during the last few decades and its use in medicine is increasing globally. Developing countries like Pakistan are lagging in the implementation of AI-based solutions in healthcare. There is a need to incorporate AI in the health system which may help not only in expediting diagnosis and management but also injudicious resource allocation. Objective: To determine the knowledge, attitude, and practice of AI among doctors and medical students in Pakistan. Materials and methods: We conducted a cross-sectional study using an online questionnaire-based survey regarding demographic details, knowledge, perception, and practice of AI. A sample of 470 individuals including doctors and medical students were selected using the convenient sampling technique. The chi-square test was applied for the comparison of variables. Results: Out of 470 individuals, 223(47.45%) were doctors and 247(52.55%) were medical students. Among these, 165(74%) doctors and 170(68.8%) medical students had a basic knowledge of AI but only 61(27.3%) doctors and 48(19.4%) students were aware of its medical applications. Regarding attitude, 237(76.7%) individuals supported AI's inclusion in curriculum, 368(78.3%) and 305(64.9%), 281(59.8%) and 269(57.2%) acknowledged its necessity in radiology, pathology, and COVID-19 pandemic respectively. Conclusion: The majority of doctors and medical students lack knowledge about AI and its applications, but had a positive view of AI in the field of medicine and were willing to adopt it.

Light microscopy and scanning electron microscopy: A helping tool to identify the adultrant of dye from Curcuma longa L rhizome, and its ecofriendly applications on pharmaceutical products.

The current study was embraced to examine the morphoanatomical distinguishing proof utilizing light microscopy (LM), scanning electron microscopy (SEM) and antibacterial activities of turmeric extract utilizing amoxicillin and ciprofloxacin. Cross over part of the rhizome is roundabout in structure. The peripheral layer is the periderm which comprises of 6-7 layers of digressively lengthened cells. This is trailed by an expansive cortex made of flimsy walled parenchyma cells with intercellular spaces. The antibacterial activities of turmeric extract in blend with drug items like amoxicillin and ciprofloxacin was likewise examined at various fixations. Different turmeric samples and drug items were gathered from various shops of Lahore. The samples were analyzed for antibacterial activities by utilizing pour plate method. In general outcomes showed fundamentally higher zone of inhibition of turmeric extract in combination with ciprofloxacin and lower zone of inhibition of turmeric extract in combination with amoxicillin. It is inferred that turmeric extract have hostile impact in blend with amoxicillin. Thus, the combination of turmeric extract with antimicrobial (amoxicillin) diminished the intensity of antibiotic. The turmeric extract have more antibacterial activity in mix with ciprofloxacin. Thus, the blend of turmeric extract with antibiotic (ciprofloxacin) expanded the intensity of antibiotic. RESEARCH HIGHLIGHTS: Morphoanatomical study of Turmeric rhizome using light microscopy (LM) and scanning electron microscopy (SEM). The antibacterial activities of turmeric extract like amoxicillin and ciprofloxacin was also investigated at different concentrations.

Clinical and Microbiological Analysis of Hospital-Acquired Pneumonia Among Patients With Ischemic Stroke: A Retrospective Outlook.

Background Hospital-acquired pneumonia (HAP) is a leading cause of morbidity and mortality in patients with ischemic stroke. Our study aims to explore the clinical and microbiological aspects (culture and sensitivity) of stroke patients with a confirmed diagnosis of HAP. Methodology This retrospective cross-sectional study included a total of 232 patients with a confirmed diagnosis of HAP following ischemic stroke. HAP was diagnosed based on the timing of onset of symptoms and chest X-ray. Patients were evaluated for their demographic details and a myriad of clinical parameters including dysphagia, mechanical ventilation, mortality, spontaneous pneumothorax, and Glasgow coma scale (GCS) score. The frequencies of different microorganisms isolated from the tracheal secretions were reported. Thereafter, the percentages of resistant isolates against a plethora of antimicrobial agents were tabulated. Results Out of 232 patients, 110 were males and 122 were females with a mean age of 58.79 ± 8.62 years. Dysphagia and mechanical ventilation were present in 66.4% and 72%, respectively. The mortality rate was 30.6%. Klebsiella pneumoniae was the most frequently isolated organism (28.9%), followed by Escherichia coli (24.5%), and Pseudomonas aeruginosa (23.3%). The antimicrobial resistance patterns of most of the isolates against different antibiotics were alarmingly high. Conclusions Dysphagia and mechanical ventilation are frequently present in patients of ischemic stroke with associated HAP. The antimicrobial resistance patterns of the isolated organisms are a cause of major concern. This necessitates the need for proper sanitation and the careful use of antibiotics.

Correlation of Prolonged Corrected QT Interval With Ventricular Arrhythmias and In-Hospital Mortality Among ST-Elevation Myocardial Infarction Patients: A Mystique or Lucidity?

Background Ventricular arrhythmias (VAs) are a frequent cause of cardiovascular mortality, especially in developing countries. Prolongation of corrected QT (QTc) interval predisposes patients to life-threatening VAs. Our study aims to assess the correlation of prolonged QTc interval with VAs and in-hospital mortality among ST-elevation myocardial infarction (STEMI) patients.  Methods This cross-sectional study analyzed the data from 40 patients with a confirmed diagnosis of STEMI and prolonged QTc interval. The patients were evaluated for several characteristics including their electrocardiography (ECG) findings. The frequency of in-hospital mortality and VAs developed after admission were recorded. Spearman correlation was used to assess the correlation of prolonged QTc interval with VAs and in-hospital mortality. Results Out of 40 cases, 30 patients were males and 10 were females with a mean age hovering at 52.95 ± 10.65 years. The mean QTc interval of our patients was 512.02 ± 49.74 milliseconds (ms). A total of 11 (27.5%) patients developed VAs while 14 (35%) of the patients succumbed to the disease complications. Spearman correlation showed a strong significant positive correlation of QTc interval with VAs (rho = 0.658, p < 0.001) and in-hospital mortality (rho = 0.314, p = 0.04). Conclusion Prolonged QTc interval is positively correlated with VAs and in-hospital mortality among STEMI patients. These patients should be regularly monitored and must be managed with caution as they have increased chances to develop VAs and in-hospital mortality. There is an utmost need for curation of guidelines that aid in risk stratification and appropriate management of such patients.

Sequential adaptive elastic net approach for single-snapshot source localization.

This paper proposes efficient algorithms for accurate recovery of direction-of-arrivals (DoAs) of sources from single-snapshot measurements using compressed beamforming (CBF). In CBF, the conventional sensor array signal model is cast as an underdetermined complex-valued linear regression model and sparse signal recovery methods are used for solving the DoA finding problem. A complex-valued pathwise weighted elastic net (c-PW-WEN) algorithm is developed that finds solutions at the knots of penalty parameter values over a path (or grid) of elastic net (EN) tuning parameter values. c-PW-WEN also computes least absolute shrinkage and selection operator (LASSO) or weighted LASSO in its path. A sequential adaptive EN (SAEN) method is then proposed that is based on c-PW-WEN algorithm with adaptive weights that depend on previous solution. Extensive simulation studies illustrate that SAEN improves the probability of exact recovery of true support compared to conventional sparse signal recovery approaches such as LASSO, EN, or orthogonal matching pursuit in several challenging multiple target scenarios. The effectiveness of SAEN is more pronounced in the presence of high mutual coherence.

Physiological and molecular mechanism of defense in cotton against Verticillium dahliae.

Cotton, a natural fiber producing crop of huge importance for textile industry, has been reckoned as the backbone in the economy of many developing countries. Verticillium wilt caused by Verticillium dahliae reflected as the most devastating disease of cotton crop in several parts of the world. Average losses due to attack of this disease are tremendous every year. There is urgent need to develop strategies for effective control of this disease. In the last decade, progress has been made to understand the interaction between cotton-V. dahliae and several growth and pathogenicity related genes were identified. Still, most of the molecular components and mechanisms of cotton defense against Verticillium wilt are poorly understood. However, from existing knowledge, it is perceived that cotton defense mechanism primarily depends on the pre-formed defense structures including thick cuticle, synthesis of phenolic compounds and delaying or hindering the expansion of the invader through advanced measures such as reinforcement of cell wall structure, accumulation of reactive oxygen species (ROS), release of phytoalexins, the hypersensitive response and the development of broad spectrum resistance named as, systemic acquired resistance (SAR). Investigation of these defense tactics provide valuable information about the improvement of cotton breeding strategies for the development of durable, cost effective, and broad spectrum resistant varieties. Consequently, this management approach will help to reduce the use of fungicides and also minimize other environmental hazards. In the present paper, we summarized the V. dahliae virulence mechanism and comprehensively discussed the cotton molecular mechanisms of defense such as physiological, biochemical responses with the addition of signaling pathways that are implicated towards attaining resistance against Verticillium wilt.

The inhibition of photosynthesis under water deficit conditions is more severe in flecked than uniform irradiance in rice (Oryza sativa) plants.

Water deficit is considered the major environmental factor limiting leaf photosynthesis, and the physiological basis for decreased photosynthesis under water deficit has been intensively studied with steady irradiance. Leaves within a canopy experience a highly variable light environment in magnitude and time, but the effect of water deficit on photosynthesis in fluctuating irradiance is not well understood. Two rice cultivars with different drought tolerance, Champa and Yangliangyou 6 (YLY6), were hydroponically grown under well-watered, 15% (m/v) and 20% PEG (polyethylene glycol, 6000Da) induced water deficit conditions. The inhibition of steady-state photosynthesis in Champa is more severe than YLY6. The maximum Rubisco carboxylation capacity (Vcmax) and maximum electron transport capacity (Jmax) were decreased under 20% PEG treatment in Champa, whereas less or no effect was observed in YLY6. The induction state (IS%, which indicates photosynthesis capacity after exposure of low-light period) of both leaf photosynthetic rate (A) and stomatal conductance (gs) was highly correlated, and was significantly decreased under water deficit conditions in both cultivars. Water deficit had no significant effect on the time required to reach 50 or 90% of the maximum photosynthetic rate (T50%,A and T90%,A) after exposure to high-light level, but significantly led to a greater decrease in photosynthetic rate in the low-light period under flecked irradiance (Amin-fleck) relative to photosynthetic rate in the same light intensity of continuously low-light period (Ainitial). The lower IS% of A and more severe decrease in Amin-fleck relative to Ainitial will lead to a more severe decrease in integrated CO2 fixation under water deficit in flecked compared with uniform irradiance.

Influence of leaf vein density and thickness on hydraulic conductance and photosynthesis in rice (Oryza sativa L.) during water stress.

The leaf venation architecture is an ideal, highly structured and efficient irrigation system in plant leaves. Leaf vein density (LVD) and vein thickness are the two major properties of this system. Leaf laminae carry out photosynthesis to harvest the maximum biological yield. It is still unknown whether the LVD and/or leaf vein thickness determines the plant hydraulic conductance (Kplant) and leaf photosynthetic rate (A). To investigate this topic, the current study was conducted with two varieties under three PEG-induced water deficit stress (PEG-IWDS) levels. The results showed that PEG-IWDS significantly decreased A, stomatal conductance (gs), and Kplant in both cultivars, though the IR-64 strain showed more severe decreases than the Hanyou-3 strain. PEG-IWDS significantly decreased the major vein thickness, while it had no significant effect on LVD. A, gs and Kplant were positively correlated with each other, and they were negatively correlated with LVD. A, gs and Kplant were positively correlated with the inter-vein distance and major vein thickness. Therefore, the decreased photosynthesis and hydraulic conductance in rice plants under water deficit conditions are related to the decrease in the major vein thickness.

Biogas production generated through continuous digestion of natural and cultivated seaweeds with dairy slurry.

The technical feasibility of long term anaerobic mono-digestion of two brown seaweeds, and co-digestion of both seaweeds with dairy slurry was investigated whilst increasing the organic loading rate (OLR). One seaweed was natural (L. digitata); the second seaweed (S. Latissima) was cultivated. Higher proportions of L. digitata in co-digestion (66.6%) allowed the digester to operate more efficiently (OLR of 5kgVSm(-3)d(-1) achieving a specific methane yield (SMY) of 232LCH4kg(-1)VS) as compared to lower proportions (33.3%). Co-digestion of 66.6% cultivated S. latissima, with dairy slurry allowed a higher SMY of 252LCH4kg(-1)VS but at a lower OLR of 4kgVSm(-3)d(-1). Optimum conditions for mono-digestion of both seaweeds were effected at 4kgVSm(-3)d(-1). Chloride concentrations increased to high levels in the digestion of both seaweeds but were not detrimental to operation.

Seasonal variation of chemical composition and biomethane production from the brown seaweed Ascophyllum nodosum.

Ascophyllum nodosum, an abundant Irish brown seaweed, shows significant seasonal variation in chemical composition and biogas production. The polyphenol content is shown to be a more important factor in biogas production than ash content. High polyphenol content in summer months adversely affected biogas production; suggesting two potential harvest dates, March and October. A. nodosum harvested in October showed a relatively low level of polyphenols (2% of TS) and ash (23% of volatile solids), and exhibited a specific methane yield of 215LCH4kgVS(-1), which was 44% of theoretical yield. The highest yield per wet weight of 47m(3)CH4t(-1) was achieved in October, which is 2.9 times higher than the lowest value (16m(3)CH4t(-1)), obtained in December. The gross energy yield of A. nodosum based on the optimal biogas production can achieve 116GJha(-1)yr(-1) in October.

The effect of seasonal variation on biomethane production from seaweed and on application as a gaseous transport biofuel.

Biomethane produced from seaweed may be used as a transport biofuel. Seasonal variation will have an effect on this industry. Laminaria digitata, a typical Irish brown seaweed species, shows significant seasonal variation both in proximate, ultimate and biochemical composition. The characteristics in August were optimal with the lowest level of ash (20% of volatile solids), a C:N ratio of 32 and the highest specific methane yield measured at 327LCH4kgVS(-1), which was 72% of theoretical yield. The highest yield per mass collected of 53m(3)CH4t(-1) was achieved in August, which is 4.5 times higher than the lowest value, obtained in December. A seaweed cultivation area of 11,800ha would be required to satisfy the 2020 target for advanced biofuels in Ireland, of 1.25% renewable energy supply in transport (RES-T) based on the optimal gross energy yield obtained in August (200GJha(-1)yr(-1)).

Production of hydrogen, ethanol and volatile fatty acids through co-fermentation of macro- and micro-algae.

Algae may be fermented to produce hydrogen. However micro-algae (such as Arthrospira platensis) are rich in proteins and have a low carbon/nitrogen (C/N) ratio, which is not ideal for hydrogen fermentation. Co-fermentation with macro-algae (such as Laminaria digitata), which are rich in carbohydrates with a high (C/N) ratio, improves the performance of hydrogen production. Algal biomass, pre-treated with 2.5% dilute H2SO4 at 135°C for 15min, effected a total yield of carbohydrate monomers (CMs) of 0.268g/g volatile solids (VS). The CMs were dominating by glucose and mannitol and most (ca. 95%) were consumed by anaerobic fermentative micro-organisms during subsequent fermentation. An optimal specific hydrogen yield (SHY) of 85.0mL/g VS was obtained at an algal C/N ratio of 26.2 and an algal concentration of 20g VS/L. The overall energy conversion efficiency increased from 31.3% to 54.5% with decreasing algal concentration from 40 to 5 VS g/L.

Production of hydrogen, ethanol and volatile fatty acids from the seaweed carbohydrate mannitol.

Fermentative hydrogen from seaweed is a potential biofuel of the future. Mannitol, which is a typical carbohydrate component of seaweed, was used as a substrate for hydrogen fermentation. The theoretical specific hydrogen yield (SHY) of mannitol was calculated as 5 mol H2/mol mannitol (615.4 mL H2/g mannitol) for acetic acid pathway, 3 mol H2/mol mannitol (369.2 mL H2/g mannitol) for butyric acid pathway and 1 mol H2/mol mannitol (123.1 mL H2/g mannitol) for lactic acid and ethanol pathways. An optimal SHY of 1.82 mol H2/mol mannitol (224.2 mL H2/g mannitol) was obtained by heat pre-treated anaerobic digestion sludge under an initial pH of 8.0, NH4Cl concentration of 25 mM, NaCl concentration of 50mM and mannitol concentration of 10 g/L. The overall energy conversion efficiency achieved was 96.1%. The energy was contained in the end products, hydrogen (17.2%), butyric acid (38.3%) and ethanol (34.2%).

Potential role of phytohormones and plant growth-promoting rhizobacteria in abiotic stresses: consequences for changing environment.

Plants are sessile beings, so the need of mechanisms to flee from unfavorable circumstances has provided the development of unique and sophisticated responses to environmental stresses. Depending on the degree of plasticity, many morphological, cellular, anatomical, and physiological changes occur in plants in response to abiotic stress. Phytohormones are small molecules that play critical roles in regulating plant growth and development, as well as stress tolerance to promote survival and acclimatize to varying environments. To congregate the challenges of salinity, temperature extremes, and osmotic stress, plants use their genetic mechanism and different adaptive and biological approaches for survival and high production. In the present attempt, we review the potential role of different phytohormones and plant growth-promoting rhizobacteria in abiotic stresses and summarize the research progress in plant responses to abiotic stresses at physiological and molecular levels. We emphasized the regulatory circuits of abscisic acid, indole acetic acid, cytokinins, gibberellic acid, salicylic acid, brassinosteroids, jasmonates, ethylene, and triazole on exposure to abiotic stresses. Current progress is exemplified by the identification and validation of several significant genes that enhanced crop tolerance to stress in the field. These findings will make the modification of hormone biosynthetic pathways for the transgenic plant generation with augmented abiotic stress tolerance and boosting crop productivity in the coming decades possible.

Three dimensional (3D) structure prediction and substrate-protein interaction study of the chitin binding protein CBP24 from B. thuringiensis.

Bacillus thuringiensis is an insecticidal bacterium whose chitinolytic system has been exploited to improve insect resistance in crops. In the present study, we studied the CBP24 from B. thuringiensis using homology modeling and molecular docking. The primary and secondary structure analyses showed CBP24 is a positively charged protein and contains single domain that belongs to family CBM33. The 3D model after refinement was used to explore the chitin binding characteristics of CBP24 using AUTODOCK. The docking analyses have shown that the surface exposed hydrophilic amino acid residues Thr-103, Lys-112 and Ser-162 interact with substrate through H-bonding. While, the amino acids resides Glu-39, Tyr-46, Ser-104 and Asn-109 were shown to have polar interactions with the substrate. The binding energy values evaluation of docking depicts a stable intermolecular conformation of the docked complex. The functional characterization of the CBP24 will elucidate the substrate-interaction pathway of the protein in specific and the carbohydrate binding proteins in general leading towards the exploration and exploitation of the prokaryotic substrate utilization pathways.

Enhanced ethanol production from wheat straw by integrated storage and pre-treatment (ISP).

Integrated storage and pre-treatment (ISP) combines biopreservation of moist material under airtight conditions and pre-treatment. Moist wheat straw was inoculated with the biocontrol yeast Wickerhamomyces anomalus, the xylan degrading yeast Scheffersomyces stipitis or a co-culture of both. The samples and non-inoculated controls were stored at 4 or 15 °C. The non-inoculated controls were heavily contaminated with moulds, in contrast to the samples inoculated with W. anomalus or S. stipitis. These two yeasts were able to grow on wheat straw as sole source of nutrients. When ethanol was produced from moist wheat straw stored for four weeks at 4 °C with S. stipitis, an up to 40% enhanced yield (final yield 0.15 g ethanol per g straw dry weight) was obtained compared to a dry sample (0.107 g/g). In all other moist samples, stored for four weeks at 4 °C or 15 °C, 6-35% higher yields were obtained. Thus, energy efficient bio-preservation can improve the pre-treatment efficiency for lignocellulose biomass, which is a critical bottleneck in its conversion to biofuels.