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1.
Indian Pediatr ; 61(3): 261-264, 2024 Mar 15.
Article En | MEDLINE | ID: mdl-38469845

Strategies for free transfer of sick neonates to hospitals are in place, but reports suggest suboptimal status of the same across the country. Over 7 years, our Sick Neonate Retrieval Service (SNRS) transported 165 neonates, of whom 92.1% survived. Safe, stable transportation mandates the presence of a neonatology-trained doctor and nurse in an equipped ambulance.


Ambulances , Transportation of Patients , Infant, Newborn , Humans , Hospitals
2.
Curr Top Med Chem ; 2024 Mar 11.
Article En | MEDLINE | ID: mdl-38485679

The urgent need for novel antibiotics in the face of escalating global antimicrobial resistance necessitates innovative approaches to identify bioactive compounds. Actinomycetes, renowned for their prolific production of antimicrobial agents, stand as a cornerstone in this pursuit. Their diverse metabolites exhibit multifaceted bioactivities, including potent antituberculosis, anticancer, immunomodulatory, immuno-protective, antidiabetic, etc. Though terrestrial sources have been exploited significantly, contemporary developments in the field of antimicrobial drug discovery have put marine actinomycetes in a prominent light as a promising and relatively unexplored source of novel bioactive molecules. This is further boosted by post-genomic era advances like bioinformatics-based secretome analysis and reverse engineering that have totally revitalized actinomycetes antibiotic research. This review highlights actinomycetes-based chemically diverse scaffolds and clinically validated antibiotics along with the enduring significance of actinomycetes from untouched ecosystems, especially with recent advanced techniques in the quest for next-generation antimicrobials.

3.
Sci Rep ; 14(1): 1625, 2024 01 18.
Article En | MEDLINE | ID: mdl-38238388

Water stress is an important factor that substantially impacts crop production. As a result, there is a need for various strategies that can mitigate these negative effects. One such strategy is the application of potassium humate (Kh) and cobalt (Co), which have been reported to enhance the resistance of crop plants. Therefore, the present experiment was designed to investigate whether the application of Kh and Co could positively affect proline, chlorophyll and mineral elements contents, and antioxidant defense systems which in turn will mitigate the negative impact of water stress under different irrigation strategies. In 2021 and 2022, an open-field experiments were conducted by using a split-plot design. The main plots were divided to represent different irrigation strategies (ST), with additional control of full irrigation requirements (ST1). Four STs were implemented, with ST1, followed by the application of 75%, 50%, and 25% irrigation strategies in ST2, ST3, and ST4 respectively, in the next irrigation, followed by the full requirements, and so on. In the subplots, peanut plants were treated with tap water (Control), Kh at 2 g l-1 and 3 g l-1, Co, Co + Kh 2 g l-1 and Co + Kh 3 g l-1. The yield was negatively affected by the implementation of ST4, despite the increase in proline contents. Furthermore, there was a decrease in relative water content, chlorophyll content, antioxidant enzymes, protein, and mineral nutrient elements. However, the application of Kh or Co showed better improvements in most of the studied parameters. It is worth noting that there was an antagonistic relationship between Co and iron/manganese, and the intensity of this relationship was found to depend on the STs implemented. The highest mineral nutrient accumulation, chlorophyll content, relative water content, protein content, oil content, seed yield, and water productivity were observed when peanut plants were treated with Kh 3 g l-1 + Co under the ST2 water strategy.


Antioxidants , Arachis , Antioxidants/metabolism , Arachis/metabolism , Potassium/metabolism , Dehydration , Cobalt , Proline/metabolism , Interleukin-1 Receptor-Like 1 Protein , Minerals , Chlorophyll/metabolism , Homeostasis , Nutrients
4.
Curr Top Med Chem ; 2024 Jan 29.
Article En | MEDLINE | ID: mdl-38288803

During and after the COVID-19 pandemic,Tuberculosis (TB) has reestablished with higher figures due to interruptions in the Directly Observed Treatment Short course (DOTS) despite underreporting. The rising consequences would have extended to extra-pulmonary forms of TB as well, including Tuberculous Meningitis (TBM). Considering the fact that TBM is the most dangerous and worst form of TB, we found the need to scan the literature to highlight various aspects of TBM. Epidemiology of TBM is proportionally less frightening, but the consequent mortalities and morbidities are more alarming than pulmonary TB. Here, we address critical research gaps in Tuberculous Meningitis that warrant further investigations. The highlighted aspects encompass a comprehensive understanding of TBM's clinical presentation and improved diagnostic tools for timely detection, the exploration of innovative chemotherapies and surgical interventions, the unraveling of the role of the blood-brain barrier in disease onset, investigating of the contributions of various brain cells to TBM development, deciphering the complex inflammatory response, exploring the involvement of Matrix Metalloproteinases in tissue damage, delving into host-pathogen genetics influencing susceptibility, utilizing robust in-vivo and in-vitro models for mechanistic insights, and more importantly between TBM and SARS-COVID-19 are discussed. Addressing these gaps will substantially advance our understanding of TBM's complex pathogenesis, contributing to more effective diagnostic, therapeutic, and preventive strategies against this debilitating disease.

5.
Heliyon ; 10(1): e21980, 2024 Jan 15.
Article En | MEDLINE | ID: mdl-38226244

This research is based on the analysis of Monkeypox transmission, from may 7, 2022 to October 11, 2022, in 30 most affected countries around the globe. The most affected countries are selected through the cut point of at least 100 reported confirmed cases of infected persons over the aforementioned time span. We novely argue the exhibition of distributional similarities between the viral flow and well known power law in context of this neglected zoonotic disease. Moreover, model-based evidence suggesting the capability of pathogen to spread far and wide around its nucleus, are collected and presented. It is estimated that 70 % of the reported confirmed cases belonged to 20 % of the top most affected countries. Also, 70 % of the reported transmission was inflicted in 34 % of the days of reporting at least one case, on average.

6.
Sci Rep ; 13(1): 12924, 2023 08 09.
Article En | MEDLINE | ID: mdl-37558811

Peppermint has gained a promising status due to the presence of a high proportion of bioactive compounds, especially menthol. Due to its pharmacological efficacy, the demand for its plant-based bioactive compounds necessitates its cultivation worldwide. Brassinosteroids are polyhydroxylated sterol derivatives that regulate diverse processes and control many agronomic traits during plant growth and development. A factorial randomised pot experiment was performed in the net house to investigate the effect of 24-Epibrassinolide (EBL) on the growth, physiology, essential oil content, stomatal behaviour and trichome development of the three cultivars of peppermint. Four levels of foliage-applied EBL, viz. 0, 10-5, 10-6 and 10-7 M were applied to the three cultivars of peppermint (Kukrail, Pranjal and Tushar). Among the different treatments of EBL, the application of 10-6 M increased shoot length by 38.84, 37.59 and 36.91%, root length by 36.73, 29.44 and 33.47%, chlorophyll content by 24.20, 22.48 and 23.32%, PN by 32.88, 32.61 and 33.61%, EO content by 32.72, 30.00 and 28.84%, EO yield per plant by 66.66, 77.77 and 73.33% and menthol yield per plant by 127.27, 110 and 118.18% in Kukrail, Tushar and Pranjal respectively, compared with their respective control plants. Further, the 10-6 M EBL exhibited improved trichome size and density, cellular viability and menthol content of the oil analysed from scanning electron microscopy, confocal laser scanning microscopy and GC-MS respectively as compared to the control. In conclusion, out of different levels of EBL, two sprays of 10-6 M EBL proved effective in enhancing the morphophysiological features and productivity of mint plants, particularly for cultivar Kukrail.


Mentha piperita , Oils, Volatile , Menthol/pharmacology , Oils, Volatile/pharmacology , Trichomes , Brassinosteroids/pharmacology , Plants , Chemical Phenomena
7.
J Ayub Med Coll Abbottabad ; 35(2): 231-234, 2023.
Article En | MEDLINE | ID: mdl-37422811

BACKGROUND: Non-clear cell renal cell carcinomas are uncommon renal tumours with diverse histologically and genetically defined entities. Due to limited clinical outcomes data, no standardized management approach can be offered to these patients. This study aimed to analyse outcomes of non clear cell renal cell carcinoma after surgical resection of localized renal tumours in our population. METHODS: Patients with renal tumours who underwent partial or radical nephrectomy at the Department of Urology, from January 2010 to December 2019 were identified and evaluated, in terms of prevalence, presentation, recurrence, and survival outcome. RESULTS: Non-clear cell tumours were found in one-fourth of the total number of nephrectomies performed during this period for renal cell carcinoma (RCC). The mean age was 50.48±14.76 years (range 18-89 years) with 57% being of the male gender. The predominant types were chromophobe RCC, papillary RCC, and sarcomatoid RCC, in all non-clear cell renal tumours. Mean Recurrence Free Survival (RFS) for all tumours was 75.26±2.7 months. The projected 5 years RFS of papillary RCC, chromophobe RCC and sarcomatoid RCC were 94.2%, 84.3% and 62.5% respectively. CONCLUSIONS: RCC of non-clear-cell histology depicts excellent survival in patients with localized renal tumours. Furthermore, sarcomatoid RCC has worse recurrence free survival followed by chromophobe RCC and papillary RCC, in our population subset.


Carcinoma, Renal Cell , Kidney Neoplasms , Humans , Male , Adolescent , Young Adult , Adult , Middle Aged , Aged , Aged, 80 and over , Carcinoma, Renal Cell/epidemiology , Carcinoma, Renal Cell/surgery , Kidney Neoplasms/pathology , Nephrectomy
9.
Cureus ; 15(3): e36354, 2023 Mar.
Article En | MEDLINE | ID: mdl-37082491

Background and objective There is a dearth of studies on the clinical presentation of patients with post-pulmonary tuberculosis (PTB) sequelae and its impact on their quality of life (QoL). In light of this, we conducted this study to analyze the clinical profile and QoL in patients with post-PTB sequelae. Methods Patients with a history of treated PTB and evidence of radiological damage were enrolled prospectively from November 2018 till June 2020 to study their clinical profile and QoL as per the eligibility criteria. A detailed clinical history was taken along with posteroanterior-view chest X-rays and CT scans of the thorax with bronchial angiography in patients with hemoptysis. QoL was assessed using the Hindi version of St. George's Respiratory Questionnaire (SGRQ) for which permission was obtained from the St. George's University of London. SGRQ scores were calculated using score calculation algorithms (Microsoft Excel-based) and missing data imputation as recommended by its developer. Results A total of 174 patients were included in the analysis. The analyzed population was relatively younger (mean age: 44.27 years) with BMIs leaning toward the lower side of normal (median: 19.6 kg/m²); the majority of the patients were males (59%) and non-smokers (77%). PTB had been diagnosed clinico-radiologically in the majority (68%) of patients with non-compliance to antitubercular treatment (ATT) being reported by only 9% of patients. Multiple courses of ATT were received by about one-third of patients, mainly on a clinico-radiologic basis. Systemic hypertension (HTN) (11%) and diabetes mellitus (DM) (9%) were the most common comorbidities. The most common symptom complex found was cough, expectoration, and dyspnea (n=102, 59%). At least one incidence of massive hemoptysis was reported by 20% of patients. Bronchial artery embolization (BAE) was performed for moderate to massive hemoptysis in 26% of patients with a success rate of >90%. One-fifth of the study participants required hospitalization for exacerbation of respiratory symptoms with more than half of these (59%) requiring ventilatory support. Health-related QoL was significantly impaired as reflected by a median SGRQ total score of 45.53. The most affected domain of QoL was the activity domain (mean score: 45.47). Females had worse QoL as compared to males (p=0.0062), and so did underweight patients (p=0.048). The prolonged duration of the illness also significantly impaired the QoL (p<0.001, r=0.313). Conclusion The sequelae of PTB are under-recognized even among physicians and are frequently misdiagnosed as active PTB. The QoL is more severely affected due to residual damage. This study highlights the clinical profile of this patient population and underscores the need to recognize post-PTB sequelae as a separate entity. An important remedy to mitigate its long-term consequences is its inclusion and recognition in national and international TB guidelines to facilitate its early identification and promote further research to address its evidence-based management.

10.
Plants (Basel) ; 12(4)2023 Feb 10.
Article En | MEDLINE | ID: mdl-36840157

Due to the rising demand for essential oil in the world market, peppermint has gained an important status among aromatic and medicinal plants. It becomes imperative to optimize its performance in terms of the growth, physiological functioning and biosynthesis of specialized metabolites. A factorial randomized pot experiment was performed using three peppermint cultivars (Kukrail, Pranjal and Tushar) and five levels of leaf-applied nitrogen (N), viz. 0 (control), 0.5, 1.0, 1.5 and 2%. The phenological features, biochemical parameters, viability of root cells, stomatal and trichome behavior were assessed at 100 days after transplanting (DAT). The yield-related parameters, viz., herbage yield, essential oil content, menthol content and yield were studied at 120 DAT. The results revealed that increasing the N doses up to 1.5% enhanced all the studied parameters of peppermint, which thereafter (at the dose above 1.5% N) decreased. The variation pattern of the studied parameters was "low-high-low". Cultivar Kukrail surpassed the two other cultivars Tushar and Pranjal. Among the foliar sprays, the application of 1.5% N increased chlorophyll content and net photosynthetic rate in all three cultivars. Moreover, the essential oil (EO), EO yield and menthol yield of the plant were also increased linearly in all three cultivars as compared with their control plants. Nitrogen application enhanced the trichome size and density of the plants, as revealed through scanning electron microscopy. Furthermore, from the GC-MS studies, the EO content in the studied cultivars increased, particularly in the case of menthol, with the N application. It may be concluded that two sprays of N (1.5%) at appropriate growth stages could be beneficial for improving morphological, physio biochemical and yield attributes of peppermint.

11.
Heliyon ; 8(8): e10247, 2022 Aug.
Article En | MEDLINE | ID: mdl-36042746

The purpose of this research is to see how sex affects several haematological, biochemical and blood cell morphology in cultured brown trout, Salmo trutta fario. Different haematological parameters, for instance haemoglobin (Hb) concentration, haematocrit (Hct), red blood cell (RBC) and white blood cell (WBC) counts, mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) and serum biochemical parameters such as glucose, cholesterol, total protein, albumin, globulin, alanine aminotransferase (ALT), alkaline phosphatase (ALP), aspartate aminotransferase (AST), sodium, potassium and phosphorus were analysed. Throughout the study period, male fish had considerably greater Hb content, RBC count and Hct content than female fish, but insignificant (P > 0.05) difference in WBC count, differential leucocyte count, MCV, MCH and MCHC was seen between the two sexes of Salmo trutta fario. The majority of biochemical markers showed no significant (P > 0.05) difference, with the exception of AST, ALP, sodium, potassium, and phosphorus, which showed a significant (P < 0.05) difference. Under light microscopy, RBC and differential leukocyte count (neutrophils, lymphocytes, and monocytes) as well as thrombocytes were characterised and discriminated, revealing that the majority of the cells were normal and intact in shape. As a result of the foregoing findings, it is suggested that the data generated be used to identify the health state of fish and to determine the occurrence of various clinical and subclinical disorders, which might assist in enhancing the overall fish population production.

12.
BMC Res Notes ; 15(1): 214, 2022 Jun 20.
Article En | MEDLINE | ID: mdl-35725612

OBJECTIVE: Isolating high-quality RNA is a basic requirement while performing high throughput sequencing, microarray, and various other molecular investigations. However, it has been quite challenging to isolate RNA with absolute purity from plants like Crocus sativus that are rich in secondary metabolites, polysaccharides, and other interfering compounds which often irreversibly co-precipitate with the RNA. While many methods have been proposed for RNA extraction including CTAB, TriZol, and SDS-based methods, which invariably yield less and poor quality RNA and hence it necessitated the isolation of high-quality RNA suitable for high throughput applications. RESULTS: In the present study we made certain adjustments to the available protocols including modifications in the extraction buffer itself and the procedure employed. Our method led to the isolation of clear and non-dispersive total RNA with an RNA Integrity Number (RIN) value greater than 7.5. The quality of the RNA was further assessed by qPCR-based amplification of mRNA and mature miRNAs such as Cs-MIR166c and Cs-MIR396a.


Crocus , MicroRNAs , Crocus/genetics , Crocus/metabolism , Plants , Polysaccharides , RNA, Messenger
13.
PLoS One ; 17(3): e0260771, 2022.
Article En | MEDLINE | ID: mdl-35349570

With the development of distributed generation and the corresponding importance of the P.V. (photovoltaic) system, it is desired to operate a P.V. system efficiently and reliably. To ensure such an operation, a monitoring system is required to diagnose the health of the system. This paper aims to analyze a P.V. system under various operating conditions to identify parameters-derived from the I-V (current-voltage) characteristics of the P.V. system-that could serve as electrical signatures to various faulty operations and facilitate in devising a monitoring algorithm for the system. A model-based approach has been adopted to represent a P.V. system, using a one-diode model of a practical P.V. cell, developed in MATLAB/Simulink. The modelled system comprises two arrays, while each array has two panels in series. It was simulated for various operating conditions: healthy condition represented by STC (Standard Testing Condition), O.C. (open-circuited), soiling, P.S. (partial-shading), H.S. (panels hotspots) and P.D. (panels degradation) conditions. For the analysis of I-V curves under these conditions, six derived parameters were selected: Vte (equivalent thermal voltage), MCPF (maximum current point factor), Ri (currents ratio), S (slope), and Dv and Di (voltages and currents differences, respectively). Using these parameters, data of the actual system under various conditions were compared with its model-generated data for healthy operating conditions. Thresholds were set for each parameter's value to mark normal operation range. It was observed that almost each considered fault creates a unique combination of sensitive parameters whose values exceeds the pre-defined thresholds, creating an electrical signature that will appear only when the corresponding conditions on the system are achieved. Based on these signatures, an algorithm has been proposed in this study which aims to identify and classify the considered faults. In comparison to other such studies, this work has been focused on those sensitive parameters for faults identification which shows greater sensitivity and contribute more to creation of unique sets of sensitive parameters for considered faults.

14.
Nat Commun ; 13(1): 1228, 2022 Mar 09.
Article En | MEDLINE | ID: mdl-35264570

Crystalline materials with broken inversion symmetry can exhibit a spontaneous electric polarization, which originates from a microscopic electric dipole moment. Long-range polar or anti-polar order of such permanent dipoles gives rise to ferroelectricity or antiferroelectricity, respectively. However, the recently discovered antiferroelectrics of fluorite structure (HfO2 and ZrO2) are different: A non-polar phase transforms into a polar phase by spontaneous inversion symmetry breaking upon the application of an electric field. Here, we show that this structural transition in antiferroelectric ZrO2 gives rise to a negative capacitance, which is promising for overcoming the fundamental limits of energy efficiency in electronics. Our findings provide insight into the thermodynamically forbidden region of the antiferroelectric transition in ZrO2 and extend the concept of negative capacitance beyond ferroelectricity. This shows that negative capacitance is a more general phenomenon than previously thought and can be expected in a much broader range of materials exhibiting structural phase transitions.

15.
Plant Cell Rep ; 41(3): 619-637, 2022 Mar.
Article En | MEDLINE | ID: mdl-34383122

KEY MESSAGE: Stacking Glutathione-Ascorbate pathway genes (PgSOD, PgAPX, PgGR, PgDHAR and PgMDHAR) under stress inducible promoter RD29A imparts significant tolerance to drought and salinity stress in Solanum lycopersicum. Although the exposure of plants to different environmental stresses results in overproduction of reactive oxygen species (ROS), many plants have developed some unique systems to alleviate the ROS production and mitigate its deleterious effect. One of the key pathways that gets activated in plants is ascorbate glutathione (AsA-GSH) pathway. To demonstrate the effect of this pathway in tomato, we developed the AsA-GSH overexpression lines by stacking the genes of the AsA-GSH pathway genes isolated from Pennisetum glaucoma (Pg) including PgSOD, PgAPX, PgGR, PgDHAR and PgMDHAR under stress inducible promoter RD29A. The overexpression lines have an improved germination and seedling growth with concomitant elevation in the survival rate. The exposure of transgenic seedlings to varying stress regiments exhibited escalation in the antioxidant enzyme activity and lesser membrane damage as reflected by decreased electrolytic leakage and little accumulation of malondialdehyde and H2O2. Furthermore, the transgenic lines accumulated high levels of osmoprotectants with increase in the relative water content. The increased photosynthetic activity and enhanced gaseous exchange parameters further confirmed the enhanced tolerance of AsA-GSH overexpression lines. We concluded that pyramiding of AsA-GSH pathway genes is an effective strategy for developing stress resistant crops.


Droughts , Solanum lycopersicum , Antioxidants/metabolism , Ascorbic Acid/metabolism , Glutathione/metabolism , Hydrogen Peroxide/metabolism , Solanum lycopersicum/metabolism , Reactive Oxygen Species/metabolism , Salt Stress/genetics , Seedlings , Stress, Physiological/genetics
16.
Sci Rep ; 11(1): 16574, 2021 08 16.
Article En | MEDLINE | ID: mdl-34400729

Cold stress is considered as one of the major environmental factors that adversely affects the plant growth and distribution. Therefore, there arises an immediate need to cultivate effective strategies aimed at developing stress-tolerant crops that would boost the production and minimise the risks associated with cold stress. In this study, a novel cold-responsive protein1 (BoCRP1) isolated from Brassica oleracea was ectopically expressed in a cold susceptible tomato genotype Shalimar 1 and its function was investigated in response to chilling stress. BoCRP1 was constitutively expressed in all the tissues of B. oleracea including leaf, root and stem. However, its expression was found to be significantly increased in response to cold stress. Moreover, transgenic tomato plants expressing BoCRP1 exhibited increased tolerance to chilling stress (4 °C) with an overall improved rate of seed germination, increased root length, reduced membrane damage and increased accumulation of osmoprotectants. Furthermore, we observed increased transcript levels of stress responsive genes and enhanced accumulation of reactive oxygen species scavenging enzymes in transgenic plants on exposure to chilling stress. Taken together, these results strongly suggest that BoCRP1 is a promising candidate gene to improve the cold stress tolerance in tomato.


Brassica/genetics , Cold-Shock Response/genetics , Genes, Plant , Plant Proteins/physiology , Plants, Genetically Modified/genetics , Solanum lycopersicum/genetics , Amino Acid Sequence , Brassica/physiology , Cold Temperature , Conserved Sequence , Free Radical Scavengers , Germination/genetics , Solanum lycopersicum/physiology , Organ Specificity , Osmotic Pressure , Phylogeny , Plant Proteins/genetics , Plant Structures/metabolism , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , RNA, Plant/biosynthesis , RNA, Plant/genetics , Reactive Oxygen Species/metabolism , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Seedlings/growth & development , Sequence Alignment , Sequence Homology, Amino Acid
17.
Environ Monit Assess ; 193(7): 427, 2021 Jun 18.
Article En | MEDLINE | ID: mdl-34143311

Arid environments face extreme risk from contemporary climate change; therefore, predicting the shifts in species distribution range and niche breadth in these environments assumes urgent research priority. Here we report the potential distribution and predict future distribution range of two model plant species typically representing contrasting environments across Asia and Africa: hot-arid Ephedra foliata and cold-arid E. gerardiana. We adopted a comparative modelling approach and used occurrence points from extensive field surveys, supplemented with herbaria records and publicly available distribution data. Our study reveals that currently an area of 8.797334 × 106 km2 (8.8%) is potentially suitable for E. foliata and nearly half 4.759326 × 106 km2 (4.8%) for E. gerardiana. Under future climate change scenarios, distribution range of E. foliata is predicted to expand but contract in E. gerardiana. Similarly, E. foliata showed broader niche breadth which is predicted to increase under B1 (0.097-0.125) and B2 (0.878-0.930) climatic change scenarios. In contrast, E. gerardiana had narrower niche breadth and expected to further decrease under B1 (0.081-0.078) and B2 (0.878-0.854). The most influential bioclimatic variable governing the potential distribution and niche breadth of E. foliata was the precipitation of warmest quarter, whereas that of E. gerardiana was temperature seasonality. The results from our study can help in developing potential indicator plant species for assessment and monitoring of distribution range shifts in response to changing climate in the arid environments.


Climate Change , Environmental Monitoring , Africa , Asia , Ecosystem
18.
PLoS One ; 16(5): e0251008, 2021.
Article En | MEDLINE | ID: mdl-33970938

Excessive use of agrochemicals for weed controlling infestation has serious agronomic and environmental repercussions associated. An appropriate amount of pesticide/ chemicals is essential for achieving the desired smart farming and precision agriculture (PA). In this regard, targeted weed control will be a critical component significantly helping in achieving the goal. A prerequisite for such control is a robust classification system that could accurately identify weed crops in a field. In this regard, Unmanned Aerial Vehicles (UAVs) can acquire high-resolution images providing detailed information for the distribution of weeds and offers a cost-efficient solution. Most of the established classification systems deploying UAV imagery are supervised, relying on image labels. However, this is a time-consuming and tedious task. In this study, the development of an optimized semi-supervised learning approach is proposed, offering a semi-supervised generative adversarial network for crops and weeds classification at early growth stage. The proposed algorithm consists of a generator that provides extra training data for the discriminator, which distinguishes weeds and crops using a small number of image labels. The proposed system was evaluated extensively on the Red Green Blue (RGB) images obtained by a quadcopter in two different croplands (pea and strawberry). The method achieved an average accuracy of 90% when 80% of training data was unlabeled. The proposed system was compared with several standards supervised learning classifiers and the results demonstrated that this technique could be applied for challenging tasks of crops and weeds classification, mainly when the labeled samples are small at less training time.


Agriculture/methods , Aircraft , Crops, Agricultural/classification , Deep Learning , Plant Weeds/classification , Remote Sensing Technology/methods , Algorithms , Satellite Imagery/methods , Weed Control/methods
19.
PLoS One ; 16(4): e0249436, 2021.
Article En | MEDLINE | ID: mdl-33793634

Agricultural production is vital for the stability of the country's economy. Controlling weed infestation through agrochemicals is necessary for increasing crop productivity. However, its excessive use has severe repercussions on the environment (damaging the ecosystem) and the human operators exposed to it. The use of Unmanned Aerial Vehicles (UAVs) has been proposed by several authors in the literature for performing the desired spraying and is considered safer and more precise than the conventional methods. Therefore, the study's objective was to develop an accurate real-time recognition system of spraying areas for UAVs, which is of utmost importance for UAV-based sprayers. A two-step target recognition system was developed by using deep learning for the images collected from a UAV. Agriculture cropland of coriander was considered for building a classifier for recognizing spraying areas. The developed deep learning system achieved an average F1 score of 0.955, while the classifier recognition average computation time was 3.68 ms. The developed deep learning system can be deployed in real-time to UAV-based sprayers for accurate spraying.


Deep Learning , Remote Sensing Technology/methods , Weed Control , Agriculture , Aircraft , Humans , Remote Sensing Technology/instrumentation
20.
ACS Appl Mater Interfaces ; 12(52): 57987-57995, 2020 Dec 30.
Article En | MEDLINE | ID: mdl-33320539

Transition metal dichalcogenide (TMD) materials have emerged as promising candidates for thin-film solar cells due to their wide bandgap range across the visible wavelengths, high absorption coefficient, and ease of integration with both arbitrary substrates and conventional semiconductor technologies. However, reported TMD-based solar cells suffer from relatively low external quantum efficiencies (EQE) and low open circuit voltage due to unoptimized design and device fabrication. This paper studies Pt/WSe2 vertical Schottky junction solar cells with various WSe2 thicknesses in order to find the optimum absorber thickness. Also, we show that the devices' photovoltaic performance can be improved via Al2O3 passivation, which increases the EQE up to 29.5% at 410 nm wavelength incident light. The overall resulting short circuit current improves through antireflection coating, surface doping, and surface trap passivation effects. Thanks to the Al2O3 coating, this work demonstrates a device with an open circuit voltage (VOC) of 380 mV and a short circuit current density (JSC) of 10.7 mA/cm2. Finally, the impact of Schottky barrier height inhomogeneity at the Pt/WSe2 contact is investigated as a source of open circuit voltage lowering in these devices.

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