Currently, accurate information on crop area coverage is vital for food security and industry, and there is strong demand for timely crop mapping. In this study, we used MODIS time series data to ...investigate the effect of the time series length on crop mapping. Eight time series with different lengths (ranging from one month to eight months) were tested. For each time series, we first used the Random Forest (RF) algorithm to calculate the importance score for all features (including multi-spectral data, Normalized Difference Vegetation Index (NDVI), Normalized Difference Water Index (NDWI), and phenological metrics). Subsequently, an extension of the Jeffries-Matusita (JM) distance was used to measure class separability for each time series. Finally, the RF algorithm was used to classify crop types, and the classification accuracy and certainty were used to analyze the influence of the time series length and the number of features on classification performance; the features were added one by one based on their importance scores. Results indicated that when the time series was longer than five months, the top ten features remained stable. These features were mainly in July and August. In addition, the NDVI features contributed the majority of the most significant features for crop mapping. The NDWI and data from multi-spectral bands also contributed to improving crop mapping. On the other hand, separability, classification accuracy, and certainty increased with the number of features used and the time series length, although these values quickly reached saturation. Five months was the optimal time series length, as longer time series provided no further improvement in the classification performance. This result shows that relatively short time series have the potential to identify crops accurately, which allows for early crop mapping over large areas.
COVID-19, a highly infectious respiratory disease, has been associated with a range of cardiovascular complications. One of the most commonly reported cardiovascular issues in COVID-19 patients is ...the development of arrhythmias. Among all types of arrhythmias, atrial fibrillation is the most frequently observed. Atrial fibrillation is characterized by an irregular and often rapid heartbeat, and it can be a serious and potentially life-threatening condition.
To investigate the incidence and association of new onset atrial fibrillation in COVID-19 hospitalized patients and its impact on survival.
A retrospective cross-sectional study that encompassed all patients, both positive and negative for COVID-19, who were consecutively admitted to the Aga Khan University Hospital in Karachi, a tertiary care facility, from June 2021 to December 2021.
A total of 1,313 patients who met the inclusion criteria of our study were enrolled as participants. These patients were then stratified into two groups based on COVID-19 status: the study group (COVID-19 positive) comprised 626 (47.7%) patients and the control group (COVID-19 negative) consisted of 687 (52.3%) patients. The incidence of new-onset atrial fibrillation was 85 (13.6%) in COVID-19 positive compared to 43 (5.2%) in COVID-19 negative group. The study found a strong association between COVID-19 and new-onset atrial fibrillation in both univariate (unadjusted odd ratio 2.35 95% CI, 1.60-3.45, p-value < 0.01) and a multiple-adjusted regression analysis (adjusted odd ratio 3.86 95% CI, 2.31-6.44, p-value < 0.01).
These findings highlight the importance of vigilant monitoring of cardiovascular complications in COVID-19 patients, especially those with pre-existing conditions that predispose them to the development of atrial fibrillation. The study underscores the need for prompt recognition and management of new onset atrial fibrillation in COVID-19 patients, as this may mitigate the risk of adverse outcomes and improve overall prognosis.
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•Thermocatalytic decomposition of ammonia is presented.•Ammonia as a hydrogen carrier for green hydrogen production is discussed.•Ruthenium and non-ruthenium-based catalysts for ...ammonia conversion are reviewed.•Techno-economic analysis of ammonia and hydrogen economy is discussed.•Hydrogen source, production pathways, and energy efficiency are presented.
Sustainable societal growth relies on the efficient storage, transportation, and use of renewable energies. Considerable progress has been made in sustainable hydrogen production via water electrolysis and biomass conversion, but hydrogen storage and transportation remain major challenges for commercial-scale applications. Owing to its high hydrogen content and energy density, ammonia is a promising zero-carbon energy carrier for large-scale energy storage. Therefore, the transformation of renewable hydrogen into ammonia is a promising strategy for effective hydrogen transportation and storage. Unlike the direct combustion of ammonia, which can produce NOx, catalytic cracking into nitrogen and hydrogen provides an environmentally friendly method for hydrogen regeneration. Herein, recent advances in effective ammonia decomposition via various processes, including electrochemical, photochemical, and, particularly, thermochemical routes, are summarized. In addition, hydrogen separation techniques and techno-economic analyses of the ammonia and hydrogen economy are discussed. The main objective of this review is to provide a conceptual framework for effective ammonia cracking to yield pure hydrogen as a clean fuel for developing futuristic and sustainable energy solutions.
Previous works have shown that wearable antennas can operate ideally in free space; however, degradation in performance, specifically in terms of frequency shifts and efficiency was observed when an ...antenna structure was in close proximity to the human body. These issues have been highlighted many times yet, systematic and numerical analysis on how the dielectric characteristics may affect the technical behavior of the antenna has not been discussed in detail. In this paper, a wearable antenna, developed from a new electro-textile material has been designed, and the step-by-step manufacturing process is presented. Through analysis of the frequency detuning effect, the on-body behavior of the antenna is evaluated by focusing on quantifying the changes of its input impedance and near-field distribution caused by the presence of lossy dielectric material. When the antenna is attached to the top of the body fat phantom, there is an increase of 17% in impedance, followed by 19% for the muscle phantom and 20% for the blood phantom. These phenomena correlate with the electric field intensities (V/m) observed closely at the antenna through various layers of mediums (
-axis) and along antenna edges (
-axis), which have shown significant increments of 29.7% in fat, 35.3% in muscle and 36.1% in blood as compared to free space. This scenario has consequently shown that a significant amount of energy is absorbed in the phantoms instead of radiated to the air which has caused a substantial drop in efficiency and gain. Performance verification is also demonstrated by using a fabricated human muscle phantom, with a dielectric constant of 48, loss tangent of 0.29 and conductivity of 1.22 S/m.
Abstract
The increasing population, deforestation and conversion of agricultural land to the built-up areas are putting pressure on land resources. Moreover, among land degradation, soil loss is one ...of the common issues that has had adverse consequences for natural ecosystems, thus affecting livelihoods. The Panjkora River Basin is selected as the study area due to its very fragile soil and having shown regular soil loss activity. In the study area, the scientific communities are consistently insisting on monitoring the LULC changes and exploring the extent of soil loss. To achieve the stated objectives, the RUSLE approach was applied to generate maps of soil loss for the years 1990, 2005 and 2020. The analysis revealed that during the past three decades (1990–2020), the built-up areas have been increased by 20%. Contrary to this, a decrease of 3% in barren land, 2% in area under water, 3% in snow cover and 13% in area under vegetation have been recorded. The analysis further revealed that the maximum actual annual soil loss consistently increased from 5,195 tons/ha/year in 1990 to 6,247 tons/ha/year in 2005 and 8,297 tons/ha/year in 2020. This research implies that geospatial technologies are effective tools for modeling the erosion of soil.
Using an extended constructivist position and the case study of Pukhtuns in Swat, Pakistan, this study outlines the interplay between violent conflict (between Muslim Militants and Pakistani state ...military) and National identity and its markers. The conflict is peculiar; (1) because of the use of Islam by Muslim militants which is an identity marker for Pakistani national identity and Pukhtun ethnic identity, (2) the case of Swat, an ex-princely state integrated only in 1969 in Pakistan with a history of religious violent mobilizations. Further, as Pakistani state has been facing problems with the process of national integration of its multiple ethnicities, the case of national identity becomes significant to be explored The study argues that the impacts of conflict and violence on national identity are complex and multi-dimensional. National identity is neither lost nor reaffirmed, yet as a result of the violent conflict. The article explores the impacts of violent conflict for religion (Islam), State institutions (military), discourses (of pride, sacrifice, and complains) and national symbols (holidays) as markers of National Identity in Pakistan through a fieldwork in Swat from November 2016 to May 2017 and later in November 2021.
Rock phosphate is a cheap source of soil P but it is not solublized in alkaline soils when applied directly. An incubation experiment was conducted in laboratory to assess the release of P from rock ...phosphate (RP) applied alone or in combination with humic acid (HA), farm yard manure (FYM) and effective microbes (EM) during 2016. Treatments included (T1) control, (T2); RP applied at 90 mg P2O5 ha-1 (T3); HA at 3 mg kg-1, (T4); FYM at 5 g kg-1, (T5); EM at 1 mL kg-1, (T6): RP+HA, (T7); RP+FYM, (T8); RP+EM, (T9); RP+HA+FYM, (T10); RP+HA+EM, (T11); RP+FYM+EM, (T12); RP+FYM+HA+EM and (T13) SSP fertilizer at 90 mg P2O5 ha-1. The treatments were added in one kg soil in pots following CRD with three replications. The pots were placed in incubators at 25% moisture and 30°C temperature respectively. AB-DTPA extractable P (PAB) and water soluble P (PWS) were determined in the soil at 0, 15, 30, 45, 60, 75 and 90 days of incubation whereas pH, EC, lime and organic matter were determined only at the end of study. It was noted that sole application of HA, FYM and EM yielded higher PAB, 4.22, 4.76, 4.03 mg kg-1 respectively while Pws from these treatments was 0.95, 0.88, 0.95 mg kg-1 respectively. RP+HA+FYM+EM gave the highest value of AB-DTPA extractable P (4.96 mg kg-1) and water soluble (1.69 mg L-1) at the end of incubation time. This treatment also suggested the optimum combination for higher release of P from rock phosphate and keeping it in available form in soil.
Soilless agriculture is acknowledged worldwide because it uses organic leftovers as a means of supporting intensive and efficient plant production. However, the quality of potting media deteriorates ...because of lower nutrient content and excessive shrinkage of most organic materials. A current study was undertaken to identify the optimal blend of locally available organic materials with desirable qualities for use as potting media. Therefore, different ingredients, viz., Pinus roxburghii needles, sugarcane bagasse, and farmyard manure were used alone or in combination as potting media to test their suitability by growing spinach as a test crop. Results showed that an increase in Pinus roxburghii needles and sugarcane bagasse decreased medium pH and electrical conductivity. Higher pH and electrical conductivity were recorded for the treatments having a higher farmyard manure ratio (greater than or equal to50%) in combination. Except for pine needles 100%, pH and electrical conductivity were in the recommended range. The growth attributes include, leaves plant.sup.-1, shoot length, fresh- and dry shoot weight along with plant macronutrients (nitrogen, phosphorous, and potassium) and micronutrients (iron, copper, manganese, and zinc) content were higher in treatment pine needles 50%+farmyard manure 50% followed by pine needles 25%+farmyard manure 50%+sugarcane bagasse 25%. Moreover, the particular treatment of pine needles 50%+farmyard manure 50% exhibited the highest concentrations of macro- (nitrogen, phosphorus, and potassium) as well as micronutrients (iron, copper, manganese, and zinc) in the potting media following the harvest. This study highlights the potential of utilizing agro-industrial litter/waste as a soilless growing medium for spinach production under greenhouse conditions. When employed in appropriate proportions, this approach not only addresses disposal concerns but also proves effective for sustainable cultivation. Further research is needed to investigate the use of these wastes as potting media by mixing various particle-size ingredients.
Hyperspectral Imaging (HSI) is a pertinent technique to provide meaningful information about unique objects in the medical field. This paper discusses the basic principles, imaging methods, ...comparisons, and advances in the medical applications of HSI to accentuate the importance of HSI in the medical field. To date, there are numerous tools and methods to fix the problems, but reliable medical HSI tools and methods need to be studied. The enactment and analytical competencies of HSI for medical imaging are discussed. Specifically, the recent successes and limitations of HSI in biomedical are presented to offer the readers an insight into its current potential for medical research. Lastly, we have discussed the future challenges concerning medical applications and possible ways to overcome these limitations.
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