A hybrid topological quantum state in an elemental solid.

Topology1-3 and interactions are foundational concepts in the modern understanding of quantum matter. Their nexus yields three important research directions: (1) the competition between distinct interactions, as in several intertwined phases, (2) the interplay between interactions and topology that drives the phenomena in twisted layered materials and topological magnets, and (3) the coalescence of several topological orders to generate distinct novel phases. The first two examples have grown into major areas of research, although the last example remains mostly unexplored, mainly because of the lack of a material platform for experimental studies. Here, using tunnelling microscopy, photoemission spectroscopy and a theoretical analysis, we unveil a 'hybrid' topological phase of matter in the simple elemental-solid arsenic. Through a unique bulk-surface-edge correspondence, we uncover that arsenic features a conjoined strong and higher-order topology that stabilizes a hybrid topological phase. Although momentum-space spectroscopy measurements show signs of topological surface states, real-space microscopy measurements unravel a unique geometry of topologically induced step-edge conduction channels revealed on various natural nanostructures on the surface. Using theoretical models, we show that the existence of gapless step-edge states in arsenic relies on the simultaneous presence of both a non-trivial strong Z2 invariant and a non-trivial higher-order topological invariant, which provide experimental evidence for hybrid topology. Our study highlights pathways for exploring the interplay of different band topologies and harnessing the associated topological conduction channels in engineered quantum or nano-devices.

Capacitive and Diffusive Contributions in Supercapacitors and Batteries: A Critique of b-Value and the ν-ν1/2 Model.

Electrochemical energy storage devices run on two fundamentally different processes: charge storage across the double layer and redox reactions. A satisfactory understanding of the underlying mechanism is only possible once the two contributions are deconvoluted. The b-value and the ν -ν1/2 model are two familiar steps undertaken to separate these contributions but as it is shown here both metrics are flawed, prone to misinterpretation, frequently invoked without attention to their limitations, and in need of re-examination. After exploring these flaws through the lens of a diverse set of cyclic voltammetry data we opine that use of the b-value be discouraged on account of subjectivity inherent to the metric, and the ν -ν1/2 model be replaced by the one proposed here. This new model ultimately reduces the root mean square error significantly and provides a robust tool for the evaluation of energy storage devices.

Recent Advances in Rolling 2D TMDs Nanosheets into 1D TMDs Nanotubes/Nanoscrolls.

Transition metal dichalcogenides (TMDs) van der Waals (vdW) 1D heterostructures are recently synthesized from 2D nanosheets, which open up new opportunities for potential applications in electronic and optoelectronic devices. The most recent and promising strategies in regards to forming 1D TMDs nanotubes (NTs) or nanoscrolls (NSs) in this review article as well as their heterostructures that are produced from 2D TMDs are summarized. In order to improve the functionality of ultrathin 1D TMDs that are coaxially combined with boron nitride nanotubes and single-walled carbon nanotubes. 1D heterostructured devices perform better than 2D TMD nanosheets when the two devices are compared. The photovoltaic effect in WS2 or MoS2 NTs without a junction may exceed the Shockley-Queisser limit for the above-band-gap photovoltage generation. Photoelectrochemical hydrogen evolution is accelerated when monolayer WS2 or MoS2 NSs are incorporated into a heterojunction. In addition, the photovoltaic performance of the WSe2 /MoS2  NSs junction is superior to that of the performance of MoS2 NSs. The summary of the current research about 1D TMDs can be used in a variety of ways, which assists in the development of new types of nanoscale optoelectronic devices. Finally, it also summarizes the current challenges and prospects.

Molecular identification of Leishmania tropica in mammals occurring in human-inhabited areas of a cutaneous leishmaniasis endemic focus in North-West Pakistan.

Cutaneous Leishmaniasis is endemic in the tribal district of Khyber near the Pak-Afghan border and is caused by Leishmania tropica. In Pakistan, cutaneous leishmaniasis caused by L. tropica is considered anthroponotic and is thought to be maintained by a human-sand fly-human transmission cycle. Along with humans, other mammals may also be acting as reservoir hosts of leishmaniasis in the study area. To investigate the role of non-human mammals in the transmission of leishmaniasis, blood samples were collected from 245 animals from the CL endemic district of Khyber, Pakistan. Leishmania parasite in these samples was detected by amplifying the species-specific sequences in minicircle kinetoplast DNA, using PCR. L. tropica DNA was detected in 18 (7.35%) samples, comprising 11 cows (Bos taurus), 6 goats (Capra hircus), and 1 dog (Canus lupus familiaris). Only a single cow and dog had a leishmaniasis-like lesion, and the remaining positive samples were asymptomatic. None of the tested sheep (Ovis aries) and rat (Rattus rattus, Rattus norvegicus) was positive. The present study reports the first instance of molecular detection of L. tropica in domestic animals. Our study indicates that along with humans' cows, goats and dogs may also be playing an important role in the transmission of anthroponotic cutaneous leishmaniasis in district Khyber in particular and Pakistan in general.

Adaptation of coastal defence structure as a mechanism to alleviate coastal erosion in monsoon dominated coast of Peninsular Malaysia.

The complexity of the coastal environment and the advent of climate change cause coastal erosion, which is incontrovertibly a significant concern worldwide, including Peninsular Malaysia, where, the coast is threatened by severe erosion linked to anthropogenic factors and monsoonal wind-driven waves. Consequently, the Malaysian government implemented a mitigation plan using several coastal defence systems to overcome the coastal erosion problem. This study assesses coastal erosion management strategies along a monsoon-dominated coasts by evaluating the efficacy of coastal protection structures against the coast. To this end, we analysed 244 km of the coastline of Terengganu, a federal state located on the east coast of Peninsular Malaysia. Due to a higher frequency of storms and the ensuing inception of high wave energy environments during the northeast monsoon (relative to southwest monsoon), the study area is the most impacted region in Malaysia with regard to coastal erosion. Fifty-five (55) coastal defence structures were detected along the Terengganu coastline. The Digital Shoreline Analysis System (DSAS) was utilised to compute changes in the rate statistics for various historical shoreline positions along the Terengganu coast to assess the efficacy of the defence structures. Additionally, this study acquired the perception of the existing coastal management strategies through an interview session with the concerned stakeholders. The rate statistics revealed the effectiveness and impact of the coastal defence structure on the coastline. Assessing the functionality of the coastal defence structures shed light on the present scenario of coastal erosion management. Greater efficacy and lower impact of coastal defence structures are prescribed for coastal erosion management strategies across the monsoon-dominated coast.

Kinetin Capped Zinc Oxide Nanoparticles Improve Plant Growth and Ameliorate Resistivity to Polyethylene Glycol (PEG)-Induced Drought Stress in Vigna radiata (L.) R. Wilczek (Mung Bean).

Plants are sessile and mostly exposed to various environmental stresses which hamper plant growth, development, and significantly decline its production. Drought stress is considered to be one of the most significant limiting factors for crop plants, notably in arid and semi-arid parts the world. Therefore, the present study aimed to evaluate the potential impact of different concentrations (10, 100, and 200 µg/mL) of kinetin capped zinc oxide nanoparticles (Kn-ZnONPs) on Vigna radiata (L.) R. Wilczek under varying levels (5%, 10%, 15%) of PEG-induced drought stress. ZnONPs were synthesized by a co-precipitation method using Zinc acetate as a precursor at pH-12, incinerated to 500 °C, and kinetin was used as a surface functionalizing agent. The resulting Kn-ZnONPs were characterized by various contemporary analytical techniques, including SEM, SEM-EDS, XRD, DLS, and Zeta potential and IR spectroscopy. Crystalline Kn-ZnONPs, with a zeta potential of 27.8 mV and a size of 67.78 nm, of hexagonal wurtzite structure and vibrational stretches associated with N-H, C-O, C-N, etc., were confirmed. PEG-induced drought stress significantly reduced the growth of V. radiata by declining the chlorophyll and carotenoid contents. Moreover, a significant decrease in the levels of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), soluble sugar contents, proline, protein contents, phenol, and tannin were observed compared to the control. However, the exogenous application of Kn-ZnONPs ameliorated all photosynthetic parameters by up-regulating the antioxidant defense system through the promotion of SOD, POD, CAT, and lipid peroxidation levels. The biochemical parameters, such as proteins, soluble sugars, and proline, were observed to be maximum in plants treated with 200 µg/mL Kn-ZnONPs under 5% drought stress. The application of Kn-ZnONPs also enhanced the total phenol contents, flavonoid, and tannin contents. In conclusion, the findings of this study demonstrate that the exogenous application of Kn-ZnONPs provides beneficial effects to V. radiata by attenuating the damaging effects of drought stress through the up-regulation of the antioxidant defense system and osmolytes. These results suggest that Kn-ZnONPs have potential as a novel approach to improve crop productivity under drought stress conditions.

Spatiotemporal variation in the vegetation cover of Peshawar Basin in response to climate change.

Climate factors like temperature, precipitation, humidity, and sunshine time exert a profound influence on vegetation. The intricate interplay between the two is crucial to understand in the face of changing climate to develop mitigation strategies. In the current exploration, we delve how climate variability (CV) has impacted the vegetation in the Peshawar Basin (PB) using remote sensing data tools. The trend of climatic variability was investigated using the modified Mann-Kendall test and Sen's slope statistics. The changing climatic parameters were regressed on the Moderate Resolution Imaging Spectroradiometer (MODIS) normalized difference vegetation index (NDVI). The NDVI was further analyzed for spatiotemporal variability under land surface temperature (LST) influence. Results revealed that among the climate factors, average annual temperature and solar radiation have a significant (p < 0.05) negative impact on vegetation while precipitation and relative humidity significantly (p < 0.05) influence NDVI positively. The overall positive trend shows that vegetation improved between 2001 and 2020 with time, however some years (2010, 2012, 2014, 2016, and 2017) with low NDVI. NDVI varied in space considerably due to climatic extremes brought on by CV and the urbanization of agricultural land. NDVI regressed on LST showed that there was no or very little vegetation in the grids with high LST. The study concluded that the region is significantly impacted by both CV-related extreme weather events and anthropogenic activities. The vegetation is improving, but it is in danger of being destroyed by deforestation due to CV and human activities that exacerbate the risk of future calamities. To protect vegetation and avoid disasters, there is an immense need for adaptation and mitigation measures to deal with the region's fast-changing environment. The study urges local authorities to create climate-resilient governmental policies and supports regional sustainable development and vegetation restoration.

Ultrasensitive Detection of Exosome Using Biofunctionalized Gold Nanorods on a Silver-Island Film.

Exosomes are often a promising source of biomarkers for cancer diagnosis in the early stages. Therefore, it is important to develop a sensitive and low-cost detection method. Here, we introduce a new substrate using gold nanorods (GNRs) on a silver-island film that produces a 360-fold AF647 molecule fluorescence enhancement compared to glass. The amplified fluorescence was proven theoretically by using finite difference time-domain simulation (FDTD). Utilizing the enhanced fluorescence from the substrate, GNRs attached with the biomolecules and created a sandwich immunoassay that can significantly detect human CD63 antigen on the exosome. By applying the method, the detection limit of mouse IgG goes down to 0.3 ng/mL, which is considerably better than the existing methods. Moreover, the sensitivity and accuracy for clinical plasma from six patients confirm its diagnostic feasibility. The proposed substrate can be uniformly extended to the identification of other biomarkers by modifying the antibodies on the surfaces of the GNRs.

A reversible and stable doping technique to invert the carrier polarity of MoTe2.

Two-dimensional (2D) materials can be implemented in several functional devices for future optoelectronics and electronics applications. Remarkably, recent research on p-n diodes by stacking 2D materials in heterostructures or homostructures (out of plane) has been carried out extensively with novel designs that are impossible with conventional bulk semiconductor materials. However, the insight of a lateral p-n diode through a single nanoflake based on 2D material needs attention to facilitate the miniaturization of device architectures with efficient performance. Here, we have established a physical carrier-type inversion technique to invert the polarity of MoTe2-based field-effect transistors (FETs) with deep ultraviolet (DUV) doping in (oxygen) O2and (nitrogen) N2gas environments. A p-type MoTe2nanoflake transformed its polarity to n-type when irradiated under DUV illumination in an N2gaseous atmosphere, and it returned to its original state once irradiated in an O2gaseous environment. Further, Kelvin probe force microscopy (KPFM) measurements were employed to support our findings, where the value of the work function changed from ∼4.8 and ∼4.5 eV when p-type MoTe2inverted to the n-type, respectively. Also, using this approach, an in-plane homogeneous p-n junction was formed and achieved a diode rectifying ratio (If/Ir) up to ∼3.8 × 104. This effective approach for carrier-type inversion may play an important role in the advancement of functional devices.

Copper-doped induced ferromagnetic half-metal zirconium diselenide single crystals.

Two-dimensional (2D) magnetic layered materials have attracted considerable attention in memory storage devices due to their exciting magnetic ordering. Herein, the electronic and magnetic properties of high-quality single crystals zirconium diselenide and copper (Cu)-doped zirconium diselenide as grown via chemical vapor transport technique combined with first principle density functional theory calculations were investigated. A semimetallic state is recognized for Cu0.052Zr0.93Se2 as measured through resistance versus temperature measurements and angle resolved photoemission spectroscopy (ARPES). The magnetic measurement shows diamagnetic semiconducting behaviour for ZrSe2, whereas Cu0.052Zr0.93Se2 exhibits ferromagnetic character via applying perpendicular magnetic field. Cu0.052Zr0.93Se2 reveals the room temperature magnetic moment ∼0.0125 emu g-1, while the Curie temperature is ∼363.49 K. Furthermore, first principle density functional theory (DFT) calculations show energetically long range ferromagnetic ordering in a half-metallic Cu-doped ZrSe2, while a diamagnetic state in case of ZrSe2 agrees well with experiment results. These results suggest that due to strong interaction elements at the octahedral site of zirconium atoms when replaced by copper atoms, which can change the spin ordering of electrons and make zirconium vacancy, while their magnetic moment is increased. Very importantly the half-metallic character of Cu0.052Zr0.93Se2 promotes much spin polarized electrons around the Fermi level, suggesting significant potential in future memory devices and spintronic applications.

Ferromagnetism in CVT grown tungsten diselenide single crystals with nickel doping.

Two dimensional (2D) single crystal layered transition materials have had extensive consideration owing to their interesting magnetic properties, originating from their lattices and strong spin-orbit coupling, which make them of vital importance for spintronic applications. Herein, we present synthesis of a highly crystalline tungsten diselenide layered single crystal grown by chemical vapor transport technique and doped with nickel (Ni) to tailor its magnetic properties. The pristine WSe2 single crystal and Ni-doped crystal were characterized and analyzed for magnetic properties using both experimental and computational aspects. It was found that the magnetic behavior of the 2D layered WSe2 crystal changed from diamagnetic to ferromagnetic after Ni-doping at all tested temperatures. Moreover, first principle density functional theory (DFT) calculations further confirmed the origin of room temperature ferromagnetism of Ni-doped WSe2, where the d-orbitals of the doped Ni atom promoted the spin moment and thus largely contributed to the magnetism change in the 2D layered material.

Plant growth promoting bacteria: role in soil improvement, abiotic and biotic stress management of crops.

Agricultural production-a major contributing factor towards global food supply-is highly reliant on field crops which are under severe threats ranging from poor soil quality, biotic, abiotic stresses and changing climatic conditions. To overcome these challenges, larger exertions are required to boost production of agricultural crops in a defensible mode. Since the evolution of fertilizers and pesticides, global crop productivity has experienced an unprecedented elevation, but at the cost of environmental and ecological unsustainability. To enhance the agricultural outputs in a sustainable way, the novel and eco-friendly strategies must be employed in agriculture, which would lead to reduced use of hazardous chemicals. Thus, the utilization of our knowledge about natural growth stimulators can lead to decrease reliance on fertilizers and pesticide which are widely used for increasing crop productivity. Among beneficial microbes, plant growth promoting bacteria offers excellent opportunities for their wide utilization in agriculture to manage soil quality and other factors which correspond to limited growth and yield output of major field crops. The aim of this review is to examine the potential role of plant growth stimulating bacteria in soil fertility and enabling crops to cope with biotic and abiotic challenges.

Synthesis of Ni9S8/MoS2 heterocatalyst for Enhanced Hydrogen Evolution Reaction.

We demonstrate a heterostructure Ni9S8/MoS2 hybrid with tight interface synthesized via an improved hydrothermal method. As compared to pure MoS2, the increased surface area and the shorten charge transport pathway in the layered hybrid significantly promote the photocatalytic efficiency for hydrogen evolution reaction (HER). In particularly, the optimized Ni9S8/MoS2 hybrid with 20 wt % Ni9S8 exhibits the highest photocatalytic activity with HER value of 406 µmolg-1h-1, which is enhanced by 70% compared to that of pure MoS2 nanosheets (285.0 µmolg-1h-1). Moreover, the value is 4 times more than the commercial MoS2 (92.0 µmolg-1h-1), indicating the high potential of the hybrid in the catalytic fields.

Management of textile wastewater for improving growth and yield of field mustard (Brassica campestris L.).

Disposal of industrial wastewater is a current issue of urbanization. However, this problem can be sorted out by using wastewater as an alternate source of irrigation after the addition of some amendment. In this way, the problem of disposal of wastewater not only will be resolved but also scarcity of irrigation water can be kept off in the future. The current research study was performed to evaluate the influence of different concentrations of wastewater along with canal water for enhancing growth and yield of field mustard. Plants were irrigated with different mixtures of canal water and wastewater (75:25, 50:50, 25:75, and 00:100) in addition to canal water as control. The results revealed that application of 50:50% waste and canal water improved plant height, the number of pods plant-1, pod length, root length, root dry weight, shoot dry weight, 100 grain weight, grain and biomass yield plant-1, and nitrogen, phosphorus, and potassium concentration in grain and straw up to 16%, 15%, 17%, 29%, 15%, 56%, 25%, 41%, 35%, 20%, 52%, 45%, 20%, 44%, and 42%, respectively, over positive control treatment. While, nutrient uptakes and agronomic efficiency of fertilizers also improved by the application of 50:50% canal and wastewater compared to positive control treatment. Furthermore, the concentration of heavy metals, predominantly Cr, Cu, Cd, and Pb, was reduced in grains by application of 50% canal water and 50% wastewater. The outcomes suggest that wastewater utilization along with canal water mixing might be an effective approach for enhancing growth and yield of field mustard.

Use of textile waste water along with liquid NPK fertilizer for production of wheat on saline sodic soils.

A field experiment in collaboration with a private textile industry (Noor Fatima Fabrics Private (Ltd.), Faisalabad) was conducted to evaluate the effect of disposed water from bleaching unit, printing unit and end drain for improving growth and yield of wheat under saline sodic soil. Textile waste water along with canal water (control) was applied with and without liquid NPK fertilizer. The application of liquid NPK fertilizer with end drain waste water increased plant height, spike length, flag leaf length, root length, number of tillers (m(-2)), number of fertile tillers (m(-2)), 1000 grain weight, grain yield, straw yield and biological yield up to 21, 20, 20, 44, 17, 20, 14, 44, 40 and 41%, respectively compared to canal water (control). Similarly, the NPK uptake in grain was increased up to 15, 30 and 28%, respectively by liquid fertilizer treated end drain water as compare to canal water with liquid fertilizer. Moreover, concentration of different heavy metals particularly Cu, Cr, Pb and Cd was decreased in grains by application of waste water along with liquid NPK. The result may imply that waste water application along with liquid-NPK could be a novel approach for improving growth and yield of wheat in saline sodic soils.

Improving the electrical properties of graphene layers by chemical doping.

Although the electronic properties of graphene layers can be modulated by various doping techniques, most of doping methods cost degradation of structural uniqueness or electrical mobility. It is matter of huge concern to develop a technique to improve the electrical properties of graphene while sustaining its superior properties. Here, we report the modification of electrical properties of single- bi- and trilayer graphene by chemical reaction with potassium nitrate (KNO3) solution. Raman spectroscopy and electrical transport measurements showed the n-doping effect of graphene by KNO3. The effect was most dominant in single layer graphene, and the mobility of single layer graphene was improved by the factor of more than 3. The chemical doping by using KNO3 provides a facile approach to improve the electrical properties of graphene layers sustaining their unique characteristics.

Phytoremediation of heavy metals spiked soil by Celosia argentea L.: effect on plant growth and metal stabilization.

Soil contaminated with heavy metals cause serious threat to the soil quality, biota, and human. The removal or stabilization of heavy metals through plants is an environment friendly approach. The aim of study was to assess the potential of Celosia argentea L. for the phytoremediation of heavy metals contaminated soil. Soil was spiked with different levels (0, 100, 200, 300, and 400 mg/kg) of chromium (Cr), copper (Cu), lead (Pb), and Zn (Zn). Experiment was carried out in greenhouse and impact of heavy metals was evaluated on plant by assessing the germination rate and plant growth. To evaluate either plant has potential to extract/stabilize the heavy metals, concentration in roots and shoot, translocation factor (TF), bioconcentration factor (BCF), and bioaccumulation factor (BAF) were determined. Application of heavy metals significantly affected the germination rate and minimum (26.6%) was observed in Cr spiked soil (400 mg/kg). Moreover, the biomass of C. argentea was also affected by the application of heavy metals. However, the concentration of heavy metals in roots and shoots were low. The BCF and BAF of C. argentea was lower than 1 except at lower levels of Pb and Zn, but the TF was greater than 1. The TF showed that plants have capability to transfer heavy metals to shoots once they are taken up by roots. However, based on the BCF and concentrations of heavy metals in shoots, it is evident that plant could play important role in the phytostabilization of heavy metals polluted soil.

Evidence of Higher Order Phonon Anharmonicity in Gray Arsenic Crystal.

Phonons play a key role in the heat transport process of quantum materials. The understanding of thermal behaviors of phonons will be beneficial for designing modern electronic devices. In this study, we utilize specific heat, Raman spectroscopy, and first-principles calculations combined with the phonon Boltzmann transport equation to explore the thermal transport of gray arsenic. Our specific heat data indicate the presence of the phonon anharmonicity at high temperature. This is further supported by temperature-dependent Raman data showing evident phonon softening and line width broadening. More interestingly, from the analysis of temperature-dependent Raman modes, we found that the four-phonon scattering process is indispensable for interpreting the line width broadening at high temperatures. Moreover, we evaluate the importance of the four-phonon scattering process in the heat transport of gray arsenic using the moment tensor potential method. Our work sheds light on the importance of a higher order phonon scattering process in heat transport of the materials with moderate thermal conductivity.

Multivariate analysis of the summer herbaceous vegetation and environmental factors of the sub-tropical region.

Understanding the distribution of the plant species of an unexplored area is the utmost need of the present-day. In order to collect vegetation data, Quadrat method was used having size of 1 m2. The composite soil samples from each site were tested for various edaphic properties. PC-ORD v.5 was used for the classification of the vegetation while CANOCO v.5.1 was used for ordination of the data and to find out the complex relationship between plants and environment. Survey was conducted during summer season and a total of 216 herbaceous species were recorded from forty different sites of District Kohat, Pakistan. Cluster Analysis (CA) and Two-Way Cluster Analysis (TWCA) classified the vegetation of forty sites into six major plant groups i.e., 1. Paspalum paspalodes, Alternanthera sessilis, Typha domingensis, 2. Cynodon dactylon, Parthenium hysterophorus, Brachiaria ramosa, 3. Cynodon dactylon, Eragrostis minor, Cymbopogon jwarancusa, 4. Cymbopogon jwarancusa, Aristida adscensionis, Boerhavia procumbens, 5. Cymbopogon jwarancusa, Aristida adscensionis, Pennisetum orientale and 6. Heteropogon contortus, Bothriochloa ischaemum, Chrysopogon serrulatus. They were named after the dominant species based on their Importance Value (IV). The detrended correspondence analysis (DCA) analysis further confirmed the vegetation classification. Canonical correspondence analysis (CCA) indicated that the species distribution in the area was strongly affected by various environmental factors including status, soil characteristics, topography and altitude.