A machine learning approach to investigate the impact of land use land cover (LULC) changes on groundwater quality, health risks and ecological risks through GIS and response surface methodology (RSM).

Groundwater resources are enormously affected by land use land cover (LULC) dynamics caused by increasing urbanisation, agricultural and household discharge as a result of global population growth. This study investigates the impact of decadal LULC changes in groundwater quality, human and ecological health from 2009 to 2021 in a diverse landscape, West Bengal, India. Using groundwater quality data from 479 wells in 2009 and 734 well in 2021, a recently proposed Water Pollution Index (WPI) was computed, and its geospatial distribution by a machine learning-based 'Empirical Bayesian Kriging' (EBK) tool manifested a decline in water quality since the number of excellent water category decreased from 30.5% to 28% and polluted water increased from 44% to 45%. ANOVA and Friedman tests revealed statistically significant differences (p < 0.0001) in year-wise water quality parameters as well as group comparisons for both years. Landsat 7 and 8 satellite images were used to classify the LULC types applying machine learning tools for both years, and were coupled with response surface methodology (RSM) for the first time, which revealed that the alteration of groundwater quality were attributed to LULC changes, e.g. WPI showed a positive correlation with built-up areas, village-vegetation cover, agricultural lands, and a negative correlation with surface water, barren lands, and forest cover. Expansion in built-up areas by 0.7%, and village-vegetation orchards by 2.3%, accompanied by a reduction in surface water coverage by 0.6%, and 2.4% in croplands caused a 1.5% drop in excellent water and 1% increase in polluted water category. However, ecological risks through the ecological risk index (ERI) exhibited a lower risk in 2021 attributed to reduced high-risk potential zones. This study highlights the potentiality in linking LULC and water quality changes using some advanced statistical tools like GIS and RSM for better management of water quality and landscape ecology.

Boosting Photocatalytic Hydrogen Production by MOF-derived Metal Oxide Heterojunctions with a 10.0% Apparent Quantum Yield.

Photocatalytic hydrogen production offers an alternative pathway to establish a sustainable energy economy. While numerous photoactive materials exhibit potential for generating hydrogen from water, the synergy achieved by combining two different materials with complementary properties in the form of heterojunctions can significantly their photocatalytic activity. Our study describes the design and generation of the metal-organic framework-derived (MOF) metal oxide heterojunction composed of RuO2/N,S-TiO2. The RuO2/N,S-TiO2 is generated through the pyrolysis of MOFs, Ru- HKUST-1, and the amino-functionalized MIL-125-NH2. Among the various RuO2/N,S- TiO2 materials tested, the material characterized by the lowest RuO2 content, exhibited the highest hydrogen evolution rate, producing 10,761 µmol·hr-1·g-1 of hydrogen with an apparent quantum-yield of 10.0% in pure water. In addition to RuO2/N,S-TiO2, we generated two other MOF-derived metal-oxide heterojunctions, ZnO/N,S-TiO2 and In2O3/N,S-TiO2, leading to apparent quantum yields of 0.7% and 0.3%, respectively. The remarkable photocatalytic activity observed in RuO2/N,S-TiO2 is thought to be attributed to the synergistic effects arising from the combination of metallic properties inherent in the metal oxides, their band alignment, porosity, and surface properties inherited from the parent MOFs. The photocatalytic efficiency of RuO2/N,S-TiO2 was further demonstrated in actual water samples, producing hydrogen with a rate of 8,190 µmol·hr-1·g-1 in tap water.

Impact of Top Electrodes (Cu, Ag, and Al) on Resistive Switching behaviour of Cu-rich Cu2 ZnSnS4 (CZTS) Ideal Kesterite.

Cu2 ZnSnS4 (CZTS) active material-based resistive random-access memory (RRAM) devices are investigated to understand the impact of three different Cu, Ag, and Al top electrodes. The dual resistance switching (RS) behaviour of spin coated CZTS on ITO/Glass is investigated up to 102 cycles. The stability of all the devices (Cu/CZTS/ITO, Ag/CZTS/ITO, and Al/CZTS/ITO) is investigated up to 103  sec in low- (LRS) and high- (HRS) resistance states at 0.2 V read voltage. The endurance up to 102 cycles with 30 msec switching width shows stable write and erase current. Weibull cumulative distribution plots suggest that Ag top electrode is relatively more stable for set and reset state with 33.61 and 25.02 shape factors, respectively. The charge carrier transportation is explained by double logarithmic plots, Schottky emission plots, and band diagrams, substantiating that at lower applied electric field intrinsic copper ions dominate in Cu/CZTS/ITO, whereas, at higher electric filed, top electrodes (Cu and Ag) dominate over intrinsic copper ions. Intrinsic Cu+ in CZTS plays a decisive role in resistive switching with Al electrode. Further, the impedance spectroscopy measurements suggest that Cu+ and Ag+ diffusion is the main source for the resistive switching with Cu and Ag electrodes.

Low power highly flexible BiFeO3-based resistive random access memory (RRAM) with the coexistence of negative differential resistance (NDR).

We demonstrated the resistive random access memory characteristics for Cu (top contact)/BFO/PMMA (active layer)/ITO (bottom electrode)/PET sheet as a flexible substrate device configuration. The device showed non-volatile bipolar resistive switching characteristics with good repeatability and the coexistence of NDR for 100 cycles or more with 0.28/3.43 mW power consumption for 1st/100th cycles. The device retains its read state for 104 s or more and switches from LRS to HRS or vice versa for 103 cycles with a pulse width of 100 ms for a write-read-erase-read pulse without affecting the memory characteristics. The Weibull distribution suggests that a set state is more stable than the reset state with shape factor ß = 25.20. The device follows Ohmic behavior for the lower applied external field and Child square and Schottky emission for the higher external fields. The Joule heating, Sorets, and Fick's forces are responsible for the formation and rupturing of ionic filament. The coexistence of resistive switching and flexible strength of the device sustains the bending curvature of infinity, 0.2 cm, 1 cm, 1.7 cm, and 2.2 cm. The memory characteristics are retained under tensile conditions for 100 cycles or more. More interestingly, the power consumption for sustaining the NDR region with bending (19 µW) is much lower than without bending (0.19 mW). Thus, this study provides the possibility of integrating BFO with flexible substrates suitable for hybrid organic/inorganic memory structures.

Bifurcation cascade, self-similarity, and duality in the three-rotor problem.

The three-rotor system concerns equally massive point particles moving on a circle subject to attractive cosine potentials of strength g. The quantum theory models chains of coupled Josephson junctions. Classically, it displays order-chaos-order behavior with increasing energy E along with a seemingly globally chaotic phase for 5.33g≲E≲5.6g. It is also known to admit pendulum and isosceles breather families of periodic orbits at all energies. While pendula display a doubly infinite sequence of stability transitions accumulating at their libration to rotation threshold at E=4g, breathers undergo only one stability transition. Here, we show that these stability transitions are associated with forward and reverse fork-like isochronous and period-doubling bifurcations. The new family of periodic orbits born at each of these bifurcations is found using an efficient search algorithm starting from a transverse perturbation to the parent orbit. The graphs of stability indices of various classes of orbits born at pendulum bifurcations meet at E=4g forming "fans." The transitions in the librational and rotational phases are related by an asymptotic duality between bifurcation energies and shapes of newly born periodic orbits. The latter are captured by solutions to a Lamé equation. We also find and numerically validate values of scaling constants for self-similarity in (a) stability indices of librational and rotational pendula and (b) shapes of newly born orbits as E→4g. Finally, we argue that none of the infinitely many families of periodic orbits we have found is stable for 5.33g≲E≲5.6g, providing further evidence for global chaos in this energy band.

Interaction of Active Janus Colloids with Tracers.

Understanding the motion of artificial active swimmers in complex surroundings, such as a dense bath of passive particulate matter, is essential for their successful utilization as cargo (drug) carriers and sensors or for medical imaging, under microscopic domains. In this study, we experimentally investigated the motion of active SiO2-Pt Janus particles (JPs) in a two-dimensional bath of smaller silica tracers dispersed with varying areal densities. Our observations indicate that when an active JP undergoes a collision with an isolated tracer, their interaction can have a significant impact on the swimmer's motion. However, the overall impact of tracers on the active JPs' motion (translation and rotation) depends on the frequency of collisions and also on the nature of the collision, which is marked by the time-duration for which the particles maintain contact during the collisions. Further, in the high-density tracer bath, our experiments reveal that the motion of the active JP results in a novel organizational behavior of the tracers on the trailing Pt (depletion of tracers) and the leading SiO2 (accumulation of tracers) side. In laboratory frame the emergence and the subsequent vanishing of the depletion zone are discussed in detail.

Exploring supercapacitance of solvothermally synthesized N-rGO sheet: role of N-doping and the insight mechanism.

We demonstrate the method of achieving excellent supercapacitance in nitrogen-doped reduced graphene oxide (N-rGO) sheets by controlling the amount of N-content through the use of different ratios of GO and urea during solvothermal synthesis. Here, urea plays a dual role in reducing GO and simultaneously doping nitrogen into the GO flakes forming exfoliated N-rGO sheets. The nitrogen content in N-rGO samples rises with an increase in the amounts of urea and saturates at a value of ∼14% for the GO : urea ratios beyond 1 : 8. The obtained N-rGO sheets with ∼ 5% N-content (obtained for GO : urea ratio of 1 : 3) were demonstrated as excellent supercapacitor materials. Using a 3-electrode setup, the maximum specific capacitance obtained for this sample was 514 F g-1 at a current density of 0.5 A g-1 (mass normalized current). The insights into the origin of this excellent supercapacitive behavior are explained through our results on optimum N-content, the relative amount of different N-environments, defects/disorders, and the degree of reduction of GO. Importantly, a proper stacking of rGO sheets with moderate N-content (∼5-6%) and a moderate amount of defects is the key to achieve high specific-capacitance. Furthermore, our 2-electrode device demonstrates the excellence of our samples with a Csp of 237 F g-1, a power density of 225 W kg-1, and an energy density of 6.7 W h kg-1 at 0.5 A g-1, exhibiting a high cyclic constancy with high capacitive retention of ∼ 82% even after 8000 cycles. Hence, our work provides a way to control the properties of N-rGO in achieving excellent supercapacitive performance.

Emissions Measurements from Household Solid Fuel Use in Haryana, India: Implications for Climate and Health Co-benefits.

A large concern with estimates of climate and health co-benefits of "clean" cookstoves from controlled emissions testing is whether results represent what actually happens in real homes during normal use. A growing body of evidence indicates that in-field emissions during daily cooking activities differ substantially from values obtained in laboratories, with correspondingly different estimates of co-benefits. We report PM2.5 emission factors from uncontrolled cooking (n = 7) and minimally controlled cooking tests (n = 51) using traditional chulha and angithi stoves in village kitchens in Haryana, India. Minimally controlled cooking tests (n = 13) in a village kitchen with mixed dung and brushwood fuels were representative of uncontrolled field tests for fine particulate matter (PM2.5), organic and elemental carbon (p > 0.5), but were substantially higher than previously published water boiling tests using dung or wood. When the fraction of nonrenewable biomass harvesting, elemental, and organic particulate emissions and modeled estimates of secondary organic aerosol (SOA) are included in 100 year global warming commitments (GWC100), the chulha had a net cooling impact using mixed fuels typical of the region. Correlation between PM2.5 emission factors and GWC (R2 = 0.99) implies these stoves are climate neutral for primary PM2.5 emissions of 8.8 ± 0.7 and 9.8 ± 0.9 g PM2.5/kg dry fuel for GWC20 and GWC100, respectively, which is close to the mean for biomass stoves in global emission inventories.

Effect of lithium salt on fluorescence quenching in glycerol: a comparison with ionic liquid/deep eutectic solvent.

It was reported earlier that the addition of LiCl to the deep eutectic solvent (DES) ChCl:Urea (composed of the salt choline chloride and the H-bond donor urea in 1 : 2 molar ratio) and the addition of LiTf2N [Tf2N:(CF3SO2)2N] to the ionic liquid (IL) [C2C1im][Tf2N] ([C2C1im]:1-ethyl-3-methylimidazolium), respectively, results in an increase in the dynamic viscosity of the medium. However, as the concentration of the Li salt is increased, instead of decreasing, the bimolecular quenching rate constant (kq) for the quenching of pyrene fluorescence by nitromethane is observed to first increase and only then decreases within both media. This unusual initial increase in quenching is hypothesized to be due to structural changes in the DES ChCl:Urea and the IL [C2C1im][Tf2N], respectively, as the Li salt is added. We tested this hypothesis by comparing the physical properties and fluorescence quenching behavior between 1 wt% water in glycerol solution which has similar viscosity to that of the DES ChCl:Urea with the aforementioned DES and IL in the presence of lithium salt as media. In complete contrast, irrespective of the temperature, kq is found to decrease monotonically with increasing concentration of LiCl within 1 wt% water in glycerol media. These findings therefore highlight the unusual characteristics of ILs and DESs as solubilizing media. The ionic nature of the IL and the high concentration of ions in the DES are deemed responsible for these outcomes.

Organocatalytic Asymmetric Hetero-Diels-Alder Reaction of in Situ Generated Dienes: Access to α,ß-Unsaturated δ-Lactones Featuring CF3-Substituted Quaternary Stereocenter.

Chiral bifunctional urea-catalyzed asymmetric direct hetero-Diels-Alder reaction between alkylidene azlactone-derived dienes and trifluoromethyl aryl ketones is reported for the first time. The direct hetero-Diels-Alder reaction followed by ring opening results in densely functionalized α,ß-unsaturated δ-lactones featuring a CF3-substituted quaternary stereocenter in high yields with excellent enantioselectivities. The method is compatible over a range of substrates. Moreover, the reaction is scaled up and the α,ß-unsaturated δ-lactones were converted to amino acid derivatives decorated with trifluoromethylated carbinol functionality.

Is complementary and alternative medicine effective in job satisfaction among dentists with musculoskeletal disorders? A cross sectional study.

BACKGROUND: Musculoskeletal disorders have serious impact on the profession of dentistry. There is common occurrence of pain due to incorrect posture in dental professionals. Complementary and alternative medicine (CAM) therapies may cast a new light on preventing and intercepting musculoskeletal disorders (MSD). An epidemiological study was conducted in an effort to contribute to the prevention of musculoskeletal disorders in dentistry. The purpose of this study was to determine the prevalence of MSD at dentists using CAM as a treatment and preventive modality for MSD and to compare job/career satisfaction between dentists who use CAM and conventional therapy (CT). MATERIAL AND METHODS: Dentists registered in Uttrakhand state, India, under the Dental Council of India and registered members of the Indian Dental Association, Uttrakhand branch (N = 1496) were surveyed. Statistical analysis was conducted using SPSS 17. RESULTS: A response rate of 84% (N = 1257) was obtained, revealing that 90% (N = 1131) had the problem of MSD. Seventy three percentage (N = 826) of dentists with MSD reported the use of CAM and CT. Complementary and alternative medicine users reported greater overall health (72.7% vs. 51%, p < 0.001), job satisfaction (61.2% vs. 35%, p < 0.001) and work efficiency compared to CT users. CONCLUSION: Complementary and alternative medicine therapies may improve quality of life, reduce work interruption and enhance job satisfaction for dentists who suffers from MSD. Through the course of their studies, dentists should be equipped with knowledge on ergonomics and CAM therapies, such as yoga and others, to help them prevent musculoskeletal disorders more effectively.

Molecular cloning and characterisation of root-specific SlREO promoter of the Indian tomato (Solanum lycopersicum L.) cultivar.

Genetic transformation is helpful in enhancing crops, utilising promoters that can be constitutive, inducible, or tissue-specific. However, the use of constitutive promoters may hinder plant growth due to energy consumption during cellular processes. To optimise transgene effects, tissue-specific promoters like root-specific ones prove valuable in addressing root-related issues and enhancing productivity. Yet, identified root-specific promoters in crop are limited. To address this gap, the expression pattern of the root-specific SlREO promoter was examined across various crops. Sequencing confirmed its identity and high homology (99%) with the NCBI database, distinct from other plants tested. Using the PLACE database, six motifs associated with root expression were identified, along with several other important elements. The 2.4kb SlREO promoter was linked to a ß-glucuronidase (GUS) reporter gene alongside the CaMV35S promoter in pRI 201-AN-GUS vectors to study its expression. Histochemistry revealed strong root-specific expression in tomato (Solanum lycopersicum ) root tissues and limited expression in stems. However, the SlREO promoter did not consistently maintain its root-specific expression in other plants. Conversely, the CaMV35S promoter exhibited constitutive expression across all tissues in various plants. This study underscores the potential of the SlREO promoter as a root-specific regulatory element, offering avenues for improving crops, particularly against environmental stresses.

Clustering pedestrians' perceptions towards road infrastructure and traffic characteristics.

In India, over 25,000 pedestrian fatalities occur due to road crashes every year. While several studies have identified possible causative factors that contribute to these fatalities, little is known about how pedestrians perceive their surrounding environment. This study attempts to bridge this gap by analysing the pedestrian perception of the built environment and traffic-related aspects considering urban roads (arterial and sub-arterial). Fourteen parameters were selected to assess pedestrian perception, and four factors were derived through factor analysis. The obtained factor scores were then subjected to two-step cluster analysis to determine whether pedestrian perception is different for people from different socio-economic demographics with varying travel behaviour. Based on the results obtained from the descriptive analysis, the respondents were most satisfied with the 'quality of streetlights at sidewalks' and 'visibility/sight distances', while they were most dissatisfied with 'pedestrian volume at sidewalks' and 'lighting facilities at crossings'. From the cluster analysis, it can be summarized that female pedestrians walk less frequently than males and perceive a higher probability of collision or near-collision incidents against male pedestrians. The study findings can aid the policymakers in the assessment of the pedestrian perception of the existing road infrastructure and suggest improvements to ensure pedestrian safety.

A comparative assessment of subjective experience in simulator and on-road driving under normal and time pressure driving conditions.

This study conducts a comparative assessment of subjective experience of real-world and simulated world driving for investigating factors leading to simulator sickness. Thirty professional car drivers drove a fixed-base driving simulator in real and simulated worlds under No Time Pressure (NTP) and Time Pressure (TP) driving conditions. Drivers rated their perceptions based on real-world driving and simulator driving experiences after each driving session with respect to three factors: simulator sickness, mental workload, and sense of presence. The structural equation model results revealed that drivers experienced high mental workload due to TP driving conditions (factor loading = 0.90) and repeated exposure to simulated world (factor loading = 0.20) which induced simulator sickness (factor loading = 0.41) and resulted in low sense of presence (factor loading = -0.18). Thus, it can be concluded that lack of experience with virtual reality induced high simulator sickness, increased mental workload, and low sense of presence.

Central-to-Axial Chirality: Asymmetric Organocatalytic Synthesis of Axially Chiral Chalcones via Exocyclic Dihydronaphthalenes.

Asymmetric synthesis of an unprecedented exocyclic dihydronaphthalene and an axially chiral naphthalene chalcone has been disclosed. Good to excellent asymmetric induction is achieved. The success is attributed to the unusual formation of exocyclic dihydronaphthalene, which plays a crucial role in ensuring axial chirality. This is the first report of exocyclic molecules capable of enabling the synthesis of axially chiral chalcones via stepwise asymmetric vinylogous domino double-isomerization using secondary amine catalysis.

Investigating the role of beliefs in influencing the hand-held and hands-free mobile phone use among pedestrians in India.

Mobile phone distraction is a significant contributor to pedestrian injuries. However, mobile phone engagement among pedestrians has been scarcely explored in a developing country like India. The present study utilized the beliefs-based theory of planned behaviour to examine the association between pedestrian beliefs towards distracted walking (behavioural, normative, and control) and their mobile phone use frequencies. Based on a survey of 560 pedestrians (64.6% males), it was found that the major use of mobile phones was for listening to music (30.7%), followed by receiving a call (25%), making a call (18.9%), texting (9.8%), navigation (8.5%) and internet browsing (7.1%). A series of multivariate ANOVAs and logistic regression models were developed to investigate the relationships between the beliefs and frequencies of mobile phone use in hands-free and hand-held conditions. Significant multivariate differences were found for behavioural and normative beliefs in hands-free conditions and all three types of beliefs in hand-held conditions. The frequency of mobile phone use was significantly predicted by normative beliefs (p < 0.001) in the hands-free condition, and by behavioural (p = 0.041) and normative beliefs (p = 0.004) in the hand-held condition. The findings may assist the road safety countermeasures in addressing the issue of pedestrian distraction.

Changing sleep patterns and anxiety due to Covid-19 home confinement among working population: A cross-sectional study.

Introduction: The COVID-19 pandemic took the entire world unawares and people were forced to stay indoors overnight. Due to this a drastic change ensued in lifestyle with many succumbing to various kinds of stresses and psychological problems. This study aims to study the changing sleep patterns and level of anxiety among the working population due to the COVID-19 Pandemic lockdown. Methodology: An online survey was conducted using a cloud-based website. The sleep patterns both prior to and during the lockdown period of the pandemic were assessed using a self-administered questionnaire. The level of anxiety during both these periods (before and during lockdown) amongst the working population was also assessed using the Generalized Anxiety Disorder Scores (GADS). Results: A total of 224 individuals participated in the study of which 52.7% were males and 47.3% were females. On analysis, the lifestyle and sleep deprivation scores showed that before the lockdown only 2.7% reported a low score out of total participants. However, this number was raised to 13.4% during the lockdown. The percentage of people reporting deteriorated sleep quality gradually increased with females reporting moderate to severe category of Generalized Anxiety Disorder scores as compared to Males. Conclusion: The study suggests that there has been a significant change in the sleep quality of the study participants due to Covid enforced lockdown which if unnoticed might lead to significant health problems. The effective use of programs like yoga, meditation, and deep breathing exercises, if followed timely could reduce psychological distress to some extent.

Modelling the pedestrian dilemma zone at uncontrolled midblock sections.

INTRODUCTION: Pedestrians at high-speed midblock crossings with the intention to cross the road usually face safety risks due to difficulty in judging the available gaps. The risk to pedestrians is high in developing nations like India since priorities are not respected by road users. Moreover, the non-yielding vehicular traffic puts pedestrians at further risk. While crossing the road, pedestrians are clear about rejecting small gaps and accepting the large gaps, however, they experience a dilemma between the small and large gaps. METHOD: This study attempts to model the dilemma zone for pedestrians intending to cross the high-speed roads (posted speed limit of 60 km/h). The field data were collected using high-definition video cameras at two uncontrolled midblock crossings, each in the cities of Mumbai and Kolhapur, located in the southwestern part of India. The variations in the spatial gap acceptance behavior were analyzed for 1,107 pedestrian observations using binary logit models. RESULTS: The findings revealed that the length and the distribution of the dilemma zone were significantly affected by the speed of the approaching vehicle and the distance from it. Moreover, the influence of vehicle type (truck, car, or two-wheeler), pedestrian type (walking alone or in a group), crossing speed, and waiting time also influenced pedestrians' gap acceptance behavior. Interestingly, pedestrians' gender did not play a significant role in their road crossing decisions. CONCLUSIONS: Overall, the study identified the dilemma zone boundaries that will help pedestrians to judge the safe gaps while crossing, and in turn, reduce the probability of pedestrian-vehicle crashes. Practical Application: The proposed dilemma zone intends to protect the pedestrians by assisting in making precise crossing decisions at high-speed midblock crossings.

Males of the parasitoid wasp, Nasonia vitripennis, can identify which fly hosts contain females.

The reproductive success of a male is limited by the number of females it can mate with. Thus, males deploy elaborate strategies to maximize access to females. In Nasonia, which are parasitoids of cyclorrhaphous flies, such reproductive strategies are thought to be restricted to competition among males for access to females in the natal patch. This study investigates whether additional strategies are present, especially the capability to identify which fly hosts contain adult females inside. Behavioural assays revealed that only one out of the four species, N. vitripennis, can distinguish which hosts specifically have adult female wasps, indicating a species-specific reproductive strategy. Results of gas chromatography-mass spectrometry analyses and behavioural data suggest that female-signature cuticular hydrocarbons (CHCs) are used as chemical cues, possibly emanating from within the host puparium. Further assays indicated that N. vitripennis males can also detect differences in the intensities of female-signature CHCs, giving them the capability to seek out hosts with maximum number of females. This study uncovers a previously unknown reproductive strategy in one of the most widely studied parasitoid wasps.