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Major progress has been made in the last five years to reduce the suffering and death caused by malaria infection worldwide. In the absence of effective preventative tools, such as vaccines, chemotherapy is a principal option to treat malaria. To date, Artemisinin-based combination therapy (ACT) is used as the most effective treatment strategy against malaria infection, which made a significant impact in reducing overall mortality and morbidity. Nevertheless, the current armamentarium of anti-malarial drugs is far from satisfactory as they have unacceptable toxic sideeffects, along with resistance to the conventional treatment regime, emphasizing the need to identify new compounds and alternative treatment strategies to stay one step ahead in this evolutionary arms race between host and parasites. Developing a vaccine would be the most desirable remedy for eliminating this deadliest parasitic disease. Furthermore, immunotherapy can also be the future to treat the inflammatory disease caused by the intracellular pathogen of the genus Plasmodium. In this pursuit, regulation of pro-inflammatory and anti-inflammatory pathways in a correct manner by maintaining optimal Treg/Th17 balance may be the key to successful immunotherapeutic treatment against malaria. In this chapter, the history and mechanism of action of some important anti-malarial drugs have been narrated, along with the future possibilities of potential therapeutic approaches against malaria.

Carbon dots (CDs) and their composites as energy storage materials and electrocatalysts have emerged as new types of quasi‐zero‐dimensional carbon materials. CDs can provide a large specific surface area, numerous electron–electron hole pairs, adjustable heteroatom doping, rich surface functional groups, and so on. However, the roles and functional mechanisms of CDs and their composite materials in the enhancement of electrochemical performance remain unclear and need to be understood in depth. Based on the most recent literature, this paper comprehensively reviews the synthesis methods and applications of various categories of CDs and their composites as electrode materials of supercapacitors, lithium‐ion batteries, sodium‐ion batteries, and potassium‐ion batteries, and as electrocatalysts for hydrogen evolution, oxygen evolution, and oxygen reduction reactions in metal–air batteries, fuel cells, and water electrolysis. To facilitate further research and development, several important aspects related to CDs and their composite materials are summarized with analysis of the technical challenges in practical applications and discussion of the possible development perspectives.

In the recent times sodium ion batteries (SIBs) have come to the forefront as an economic and resourceful alternative to lithium-ion batteries (LIBs) for powering portable electronic devices and large-scale grid storage. As the specific capacity, energy density and long cycle life of batteries depend upon the performance of anode materials; their quest is the ultimate need of the hour. Among the anode materials, the semimetallic pnictogens (As, Sb, Bi) and their compounds offer high gravimetric/volumetric capacities, but suffer from undesired volume expansion and inferior electrical conductivity. Herein, this paper reviews the recent progress in semimetallic pnictogens as alloying anodes and their compounds mainly as conversion-alloying anodes. Various debatable sodiation mechanisms (intercalation or alloying) have been presented with emphasis on in situ/ex situ advanced characterization methods well supported by theoretical modeling and calculations. The reviewed electrochemical reaction mechanisms, coherent structural designs and engineering provide a vital understanding of the electrochemical processes of Na+ ion storage. The existing challenges and perspectives are also presented, and several research directions are proposed from the aspects of special morphological design, employing conductive substrates, electrolyte additives and reducing particle size for technical and commercial success of SIBs.

Th9, a new subgroup of CD4

The soaring fidelity of spinel cobaltite system in electrochemistry presents its candidature as an electrode material for high-performance energy storage system and next generation portable devices...

Psychophysical estimates of spatial and depth vision have been shown to be better after bilateral ReLEx small-incision lenticule extraction (SMILE) refractive surgery for myopia, relative to photorefractive keratectomy (PRK) and femtosecond laser-assisted in situ keratomileusis (FS-LASIK). The present study provides the optical basis for these findings using computational image quality analysis.This study aimed to compare longitudinal changes in higher-order wavefront aberrations and image quality before and after bilateral PRK, FS-LASIK, and SMILE refractive procedures for correcting myopia.Wavefront aberrations and image quality of both the eyes of 106 subjects (n = 40 for FS-LASIK and SMILE and n = 26 for PRK) were determined pre-operatively and at 1-week, 1-month, 3-month, and 6-month post-operative intervals using computational through-focus analysis for a 6-mm pupil diameter. Image quality was quantified in terms of its peak value and its interocular difference, residual defocus that was needed to achieve peak image quality (best focus), and the depth of focus.The increase in root mean squared deviations of higher-order aberrations post-operatively was lesser after SMILE (1-month visit median [25th to 75th interquartile range], 0.34 μm (0.28 to 0.39 μm]) than after PRK (0.80 μm [0.74 to 0.87 μm]) and FS-LASIK (0.74 μm [0.59 to 0.83 μm]; P ≤ .001), all relative to pre-operative values (0.20 μm [0.15 to 0.30 μm]). The peak image quality dropped and its interocular difference increased, best focus shifted myopically by 0.5 to 0.75 D, and depth of focus widened significantly after PRK and FS-LASIK surgeries, all relative to pre-operative values (P.001). All these changes were negligible but statistically significant in a minority of instances after SMILE surgery (P ≥ .01).Although all three refractive surgeries correct myopia, the image quality and its similarity between eyes are better and closer to pre-operative values after SMILE, compared with FS-LASIK and PRK. These results can be explained from the underlying increase in higher-order wavefront aberrations experienced by the eye post-operatively.

Photocatalytic dye degradation is one of the simple and convenient ways to eliminate effluents produced by paper, plastic, printing, and textile industries. ZnS is one of the most investigated catalysts on which different modifications are applied. Here, PVP-assisted zinc sulfide (ZnS) nanopowder is prepared hydrothermally. The photoluminescence spectra signify the generated intermediate state which is attributed to sulfur (S) vacancy as obtained from the theoretical analysis. This defect-induced ZnS has shown excellent Rhodamine B (RhB) dye degradation of 95% in 100 min with dye sensitization effect under UV irradiation. Under visible light, the degradation of RhB is only 50% in the presence of ZnS. The sensitization of RhB in the presence of UV light signifies the generation of visible light through the intermediate states caused by S vacancy. However, to eliminate the disadvantage of photocatalysis in highly concentrated wastewater management and expense of UV source, RhB is degraded by sonocatalysis, and 70% of dye is removed within 100 min in the presence of ZnS nanopowder. Therefore, the efficient catalytic dye degradations are achieved employing the minimum amount of ZnS powder.

Sodium-ion batteries (SIBs) are gaining renewed interest as a promising alternative to the already commercialized lithium-ion batteries. The large abundance, low cost, and similar electrochemistry of sodium (compared with lithium) is attracting the attention of the research community for their deployment in energy storage devices. Despite the fact that there are adequate cathode materials, the choice of suitable anodes for SIBs is limited. Graphite, the most versatile anode for LIBs, exhibits poor performance in case of SIBs. Amorphous or disordered carbons (hard and soft carbon) have been the most promising and cost-effective anode materials for SIBs. This Review discusses the recent advances of various forms of amorphous or disordered carbons used in SIBs with emphasis on their synthesis processes and relationship between microstructure, morphology, and performance. A profound understanding of the charge storage mechanisms of sodium in these carbon materials has been deliberated. The performance of these anode materials also depends upon electrolyte optimization, which has been aptly conferred. However, these anodes are often plagued with large voltage loss, low initial coulombic efficiency, and formation of solid electrolyte interphase. In order to overcome these challenges, several mitigation strategies have been put forward in a concise way to offer visions for the deployment of these amorphous carbon materials for the progress and commercial success of SIBs.

Myeloid derived suppressor cells (MDSCs) are a group of heterogeneous cell populations that can suppress T cell responses. Various aspects of MDSCs in regulating immune responses in several cancer and infectious diseases have been reported till date. But the role and regulation of MDSCs have not been systematically studied in the context of malaria. This study depicts the phenotypic and functional characteristics of splenic MDSCs and how they regulate Th-17 mediated immune response during Experimental Cerebral Malaria (ECM). Flow cytometric analysis reveals that MDSCs in the spleen and bone marrow expand at 8 dpi during ECM. Among subtypes of MDSCs, PMN-MDSCs show significant expansion in the spleen but M-MDSCs remain unaltered. Functional analysis of sorted MDSCs from spleens of Plasmodium berghei ANKA (PbA) infected mice shows suppressive nature of these cells and high production of Nitric oxide (NO). Besides, MDSCs were also found to express various inflammatory markers during ECM suggesting the M1 type phenotype of these cells. In-vivo depletion of MDSCs by the use of Anti Gr-1 increases mice survival but doesn't significantly alter the parasitemia. Previously, it has been reported that Treg/Th-17 balance in the spleen is skewed towards Th-17 during ECM. Depletion of MDSCs was found to regulate Th-17 percentages to homeostatic levels and subvert various inflammatory changes in the spleen. Among different factors, IL-6 was found to play an important role in the expansion of MDSCs and expression of inflammatory markers on MDSCs in a STAT3-dependent manner. These findings provide a unique insight into the role of IL-6 in the expansion of the MDSC population which causes inflammatory changes and increased Th-17 responses during ECM.

SIGNIFICANCE Laser refractive surgery procedures are efficacious at correcting myopia, but they result in long-term deterioration of optical quality that affects monocular and binocular visual performance. The study shows that the optical quality of the two eyes needs to be similar to optimize binocular visual performance after surgery. PURPOSE This study aimed to systematically analyze longitudinal changes in optical quality, high- and low-contrast logMAR acuity and random-dot stereoacuity before and after three refractive surgery procedures for correcting myopia. METHODS A total of 106 subjects (laser-assisted in situ keratomileusis, 40; photorefractive keratectomy, 26; small-incision lenticule extraction, 40) with myopia and astigmatism ≤1.5 D participated in this prospective cohort-based study. All aforementioned outcome variables were measured in both eyes pre-operatively and 1 week and 1, 3, and 6 months post-operatively. RESULTS Pre-operative myopic spherical equivalent of refraction (median [25th to 75th interquartile range], -6.4 D [-8.0 to -4.2 D] for laser-assisted in situ keratomileusis, -4.3 D [-5.0 to -3.5 D] for photorefractive keratectomy, -5.5 D [-6.5 to -4.3 D] for small-incision lenticule extraction) was corrected to within ±0.75 D of emmetropia in all cohorts up to 6 months post-operatively (P < .001). Higher-order wavefront aberrations, uncorrected high- and low-contrast logMAR acuity, and stereoacuity all worsened and remained so up to 6 months post-operatively, relative to pre-operative values (P < .001). Stereoacuity worsened with both interocular average and difference in the magnitude of higher-order aberrations, whereas logMAR acuities worsened only with interocular average of these aberrations (r ≥ 0.40; P < .01 for all). CONCLUSIONS Although the refractive surgery procedures tested here correct myopia, they result in a sustained (up to 6 months) loss of optical quality and spatial and depth-related visual functions post-operatively. Both interocular average and difference in the eye's optical quality seem to impair binocular visual functions after refractive surgery for myopia.

High performance zinc-air batteries (ZABs) demand highly active bifunctional catalysts for both oxygen reduction reaction (ORR) and oxygen evolution reactions (OER). Herein, we report a FeCo-Co bifunctional catalyst with well-engineered interfaces between FeCo nanoalloy and metallic Co, via an alloying-degree control strategy. The FeCo-Co architecture can be obtained by manipulating the alloying degree through proper introduction of Fe, while the stacked carbon nanosheet morphology inherited from the precursor can fully expose the active sites facilitating the ion transfer. FeCo-Co interface structure enables FeCo@Co/N-C-8 catalyst to exhibit an excellent half-wave potential (0.870 V) superior to Pt/C (0.846 V) for ORR and suppressed overpotential (312 mV) than IrO2 (321 mV) for OER. The as prepared rechargeable ZAB based on FeCo@Co/N-C-8 catalyst displays an excellent peak power density of 148 mW cm-2 and an ultrahigh open circuit voltage of 1.52 V. This research provides an innovative technique in construction of bifunctional catalysts for ZABs through alloying degree control strategies.

In this work, ultrasound assisted catalytic removal of Rhodamine B (RhB) dye has been carried out in the presence of reduced Graphene Oxide enveloped Copper Phthalocyanine nanotube (RGO-CuPc) for the first time. This RGO-CuPc nanocomposite has been synthesized by in situ chemical reduction of Graphene Oxide (GO) with CuPc tube. Then our as prepared composite and pristine CuPc tubes are well characterized by various spectroscopic techniques such as X-Ray Diffraction, UV–vis and microscopic techniques like FESEM, HRTEM etc. Electrochemical EIS measurement has also been carried out to investigate charge transfer mechanism. These results confirm the purity of the as prepared samples. Efficient sonocatalytic RhB dye removal upto ∼92.22% is achieved by RGO-CuPc composite within 100 min as compared to pristine CuPc tube (∼70%). A plausible reaction pathway towards dye removal is discussed in detail. Also degradation performance in the presence of enhancer and scavenger has been investigated.

Modulation of pro-inflammatory and anti-inflammatory axis and orientation of glial cell function towards neuroinflammation, were hallmark signs of cerebral malaria (CM). CM pathogenesis was concerned with the circulating levels of Interleukin 6 (IL 6) and Transforming growth factor β (TGF β). Definite roles of these two cytokines in brain related pathology remained largely unexplored. To study the effect of these two cytokines, we have examined changes in morphology and in activation profile of the glial cells after TGF β and IL 6 neutralization during CM in cortex and cerebellum of the Plasmodium berghei ANKA (PbA) infected male swiss albino mice. PbA infection caused severe inflammation by inducing changes in morphological features as well as in activation profile of the astrocytes and microglia. Similar inflammatory signs were evident in Anti TGF β treated set. Interestingly in the Anti IL 6 treated set, reduced level of activation of these glial cells corresponds to the reduced level of inflammatory profile. Microglial activation was found to be synchronous with TLR4 engagement. Neuronal death was triggered by neuroinflammatory milieu seen in PbA and PbA+Anti TGF β treated set. In conclusion, it can be said that IL 6 and TGF β perform essential role in CM pathogenesis by modulating the level of glial cell induced neuroinflammation.

Chemically derived topological insulator Bi2Se3 nanoflake/Si nanowire (SiNWs) heterojunctions were fabricated employing all eco-friendly cost-effective chemical route for the first time. X-ray diffraction studies confirmed proper phase formation of Bi2Se3 nanoflakes. The morphological features of the individual components and time-evolved hybrid structures were studied using field emission scanning electron microscope. High resolution transmission electron microscopic studies were performed to investigate the actual nature of junction whereas elemental distributions at junction, along with overall stoichiometry of the samples were analyzed using energy dispersive X-ray studies. Temperature dependent current–voltage characteristics and variation of barrier height and ideality factor was studied between 50 and 300 K. An increase in barrier height and decrease in the ideality factor were observed with increasing temperature for the sample. The rectification ratio (I+/I–) for SiNWs substrate over pristine Si ...

In this work we have synthesized quaternary chalcogenide Cu2NiSnS4 (QC) nanoparticles grown in situ on 2D reduced graphene oxide (rGO) for application as anode material of solid-state asymmetric supercapacitors (ASCs). Thorough characterization of the synthesized composite validates the proper phase, stoichiometry, and morphology. Detailed electrochemical study of the electrode materials and ASCs has been performed. The as-fabricated device delivers an exceptionally high areal capacitance (655.1 mF cm–2), which is much superior to that of commercial micro-supercapacitors. Furthermore, a remarkable volumetric capacitance of 16.38 F cm–3 is obtained at a current density of 5 mA cm–2 combined with a very high energy density of 5.68 mW h cm–3, which is comparable to that of commercially available lithium thin film batteries. The device retains 89.2% of the initial capacitance after running for 2000 cycles, suggesting its long-term capability. Consequently, the enhanced areal and volumetric capacitances combin...

Synthesis of layered sheet like graphitic carbon nitride by pyrolysis of urea at different temperatures has been reported. The proper phase formation has been confirmed by X-ray diffraction study whereas field emission scanning and transmission electron microscope characterized the morphology of the material. Fourier transform infrared and Raman spectroscopy revealed the presence of different bonds in the sample. Thermal gravimetric analysis has been used to study the thermal stability of the material. Energy dispersive X-ray analysis further revealed the elemental composition of carbon and nitrogen in a proper stoichiometric ratio. Excitation dependent photoluminescence spectra of the as prepared samples have been studied in detail. It has been shown that synthesis condition can tailor the amount of defects present in the synthesized samples that in turn can change the photoluminescence properties of the material. The fluorescence spectra of the as prepared samples have been used to detect copper ions present in the sample. It has also been shown that the presence of defects which is mainly N-H functional groups can change the decay characteristics of the carrier in these samples which in turn changes the PL spectra.

Amorphous carbon nanotubes (a-CNTs) were synthesized by solid state reaction. The as prepared a-CNTs were characterized by X-ray diffraction, field emission scanning and high resolution transmission electron microscope and Raman spectroscopy. As-synthesized a-CNTs were used for, the first time, for removing different organic dyes from water. The dyes mainly include Rhodamine B and Methyl Orange and systematic batch mode studies of a-CNTs assisted adsorption have been executed in detail. The removing efficiency of a-CNTs has also been investigated for various sorption parameters like contact time, dosage, pH, initial dye concentration, contact time etc. It is seen that a-CNTs can be material of potential for removal of dyes. In case of Rhodamine B, the maximum time for removal was 45 min whereas for Methyl orange rapid removal was plausible in about 30 min even in ambient condition. The experimental data have been well correlated with classical Langmuir-Freundlich and Temkin adsorption models.

Fiber gaskets and sealants are used in salt water treatment plants. Due to pressure, leakage and thickness increase they get damaged and often they are to be replaced. This may be due to the rate of flow of the liquid and installation of gaskets. In order to reduce these damages and increase the lifetime of gasket or sealant, the gasket can be coated with polymers and can be used. In the present work authors have coated the gasket with PEEK of 0.2mm thickness which can increase its stability. To check the stability after coating few tests like tensile test, density test and thickness increase test were carried out. Through the test results it is evident that this gasket can reduce cost and it has an elongated lifetime.

Most of the transition metal bismuth salts have excellent visible absorption range and carrier transport properties due to their unique structure capable of orbits and s-p bonds. As one of the transition metal bismuth salts, Bi

Coalescence of unique properties of semiconductor and carbon nanotubes (CNTs) produces new advanced materials with exciting properties, which unwraps several new fields. Here, finite element modeling is employed to optimize the diameter of semiconducting zinc cadmium sulfide (Zn0.8Cd0.2S) microspheres on the wall of metallic CNTs to get the improved field emission property. Then, Zn0.8Cd0.2S microspheres are attached on COOH functionalized multiwalled CNTs (MWCNTs) by a simple one step solvothermal method for experimental corroboration. Field emission experiment shows a considerable enhancement of current density with respect to bare microspheres and functionalized CNTs. The turn-on field is found to be as low as 3V/μm at a current density of 10 μΑ/cm2 for the hybrid system. Density functional theory (DFT) calculation is carried out for the model structures of Zn0.8Cd0.2S and CNT-Zn0.8Cd0.2S to calculate the work functions. This improvement in field emission property of the hybrid system is demonstrated in terms of band bending, geometry, high field enhancement factor, low work function and electron affinity. Thus, non-field emitting microspheres with less toxicity have been transformed into a decent field emitter by the contribution of few carbon nanotubes.

This work highlights the synthesis of zinc blende ZnxCd1−xS ternary solid solutions with a tunable bandgap. Composition dependent band gaps are realized due to the effective band edge tuning of the solid solutions which in turn show decent photocatalytic behaviour. The bandgap of ZnxCd1−xS increases as Zn composition increases. It is interesting to note that the highest catalytic activity is observed for Zn0.8Cd0.2S (Eg = 2.83 eV) in the visible spectra due to the presence of defect states in the bandgap around 2.35 eV which has been explicated according to the results of photoluminescence spectra. Density of states (DOS) analysis provides further theoretical insight into the more negative conduction band edge for x = 0.8 than other samples. It also determines generation of intermediate states due to sulfur vacancy which is responsible for more electron–hole generation and the highest rate of Methyl Orange (MO) degradation under natural sunlight irradiation.

Splenomegaly, a major symptom in Plasmodium infection, is extensively studied for its immunopathological role in mice malaria model infected with Plasmodium berghei ANKA. The status of autophagic regulation in hosts in malaria pathogenesis remains unreported till date. This study demonstrated the autophagy, proteasomal degradation and NRF2-KEAP1 antioxidant pathway status in the host during Plasmodium infection taking murine spleen as our organ of interest. Initial staining and autophagic gene expression indicate a possibility of autophagic pathway activation. Although the conversion of LC3A to LC3B and lysosome-autophagosome fusion increases, the final degradation step remains incomplete. Resultant upregulation of p62 and its altered phosphorylated status enhances its binding to keap1 causing NRF2 translocation to the nucleus. NRF2 act as transcription factor upregulating p62 level itself leading to an autoinduction loop of p62 expression. Interestingly, enhancement of P62 interaction with proteasome subunit RPT1 indicates a possible role in transporting ubiquitinated cargo to proteasome complex. Ubiquitination level increased with subsequent upregulation of all three modes of proteasomal degradation i.e trypsin-like, caspase-like and especially chymotrypsin-like. Sqstm1/p62 plays a critical central role in regulating autophagy, proteasomal degradation, and NRF2-KEAP1 pathway. The incomplete autophagic flux in the final step may be a key therapeutic target, as autophagic degradation and subsequent pathogenic peptide presentation is of utmost necessity for downstream immune response.

Splenic plasmacytoid dendritic cells (pDC) possess the capability to harbor live replicative Plasmodium parasite. Isolated splenic pDC from infected mice causes malaria when transferred to naive mice. Incomplete autophagic degradation might cause poor antigen processing and poor immune response. Induction of autophagic flux by rapamycin treatment led to better prognosis by boosting pDC centered immune response against the pathogen. Splenic pDC from rapamycin-treated infected mice, caused less parasitemia in naive mice. The downregulation of adhesion with unaltered phagocytic potential of the cells post autophagic induction restricted excessive parasite burden within them. Rapamycin-treated pDC played a better role in antigen presentation. They showed higher expression of co-stimulatory molecules CD80, CD86, DEC205, MHCI. Rapamycin-treated pDC induced CD28 expression on CD8+ T cells and suppressed FasL level. This cells also influenced differentiation of effector, memory T cell population. The increase in IL10: TNFα ratio, Treg: Th17 ratio and lowering of myeloid DC: plasmacytoid DC ratio was observed. It shifted the overaggressive inflammation mediated Th1 pathway that is reported to incur host damage, to a better well-balanced cytokine profile exhibiting Th2 pathway. Autophagic flux induction within pDC proved to be beneficial in combating malarial pathogenicity.

Splenic red pulp macrophages play a critical role infiltration of infected RBC and elimination of pathogens during malarial infection. However, the efficiency of pathogenic processing and the intricate pathway followed by them to boost the downstream immune response has not been studied in details. We checked the status of autophagic regulation within the cells both before and after the infection and also modulated the autophagic flux with either its inducer or inhibitor. We found that the upregulation of autophagic gene and the corresponding pathway is correlated with better parasite clearance and survivability, with an enhanced downstream immune response. It also increases their phagocytic potential with better Lysosomal associated protein I and II synthesis. The autophagolysosome formation increases as well, and more vacuole bound LC3B protein are detected. Chemokine synthesized from Red Pulp macrophage helps in mediating the induction for recruiting neutrophil and CD4 + T cells to the splenic red pulp region. The skewing of M1 macrophage polarity is observed post autophagic induction with a better costimulatory molecule like CD80, CD86 expression and antigen presenting molecule MHC I, MHC II is observed. This study shows the possibility of an alternative or adjuvant therapy regimen for the malarial patient by inducing the autophagic pathway that targets the red pulp macrophages. This might be helpful for better pathogen degradation and processing. The subsequent clearance of parasite will result in a better outcome for the patients.

Bi2Se3 nanoflowers (NFs) and reduced graphene oxide (rGO) nanocomposite (BG) have been synthesized by a cost-effective, ecofriendly and easy hydrothermal route for the first time. Thorough characterizations confirm the phase, chemical composition and morphology of the samples. Room temperature transport measurement showed that the composite samples exhibit enhanced electrical conductivity compared to the pure Bi2Se3 nanoflowers (NFs). The possibility of using this composite in applications such as low macroscopic field emitters for cold cathode application has been investigated. For this, theoretical simulations are performed for pure and composite samples with graphene wrapping of different degrees and to evaluate the relation between the degree of rGO wrapping and the enhancement of FE properties, and the same was verified experimentally. It is observed that the enhancement factor for cold cathode emission of Bi2Se3–rGO (BG) composite is almost 5 times higher than that of pristine GO, 2.6 times that of rGO and nearly 1.5 times higher than that of pure Bi2Se3 NFs. The enhancement of the cold emission properties is attributed to suitable wrapping of rGO sheets over Bi2Se3 NFs. This produces more curvature at the nanoflakes edges and the electron affinities between the materials are favorable for the enhancement of cold cathode emission. The sample exhibiting the best FE properties also showed photoresponse properties under visible light excitation.

We report a novel hydrothermal route for the synthesis of Cu 2 NiSnS 4 (CNTS) nanoparticles. Structural characterization was done by X-ray diffraction (XRD) and Transmission electron microscopy (TEM) which confirmed the phase and crystallinity. Additional characterization was done by Raman spectroscopy, Energy dispersive spectroscopy (EDS), Field emission scanning electron microscopy (FESEM) and UV–vis spectrophotometry. The band-gap of 1.56 eV and photo response behavior indicates that CNTS is ideal for application in thin film solar cell devices. Thermoelectric study of CNTS is carried out for the first time. Thermoelectric power factor ( P ) attains the value of 603×10 −6 µW m −1 K −2 at 440 K. The value of activation energy is found to be 160 meV.

We present a general formulation of the ground state binding energy of a shallow hydrogenic impurity in spherical quantum dot with parabolic confinement, considering the effects of polarization and self energy. The variational approach within the effective mass approximation is employed here. The binding energy of an on-center impurity is computed for a $\mathrm{GaAs}$/ $\mathrm{{Al}_{x}{Ga}_{1-x}As}$ quantum dot as a function of the dot size with the dot barrier as parameter. The influence of polarization and self energy are also treated separately. Results indicate that the binding energy increases due to the presence of polarization charge, while decreases due to the self energy of the carrier. An overall enhancement in impurity binding energy, especially for small dots is noted., Comment: 9 pages, 2 figures

Chemically derived topological insulator Bi

Supercapacitors or ultracapacitors are considered as one of the potential candidates in the domain of energy storage devices for the forthcoming generations. These devices have earned their significance in numerous applications, viz., to power hybrid electric/electric vehicles and other power and electronic systems which require electrical energy for their operation. Supercapacitors are the most versatile devices which are most widely used for delivery of electrical energy in short time and in arenas which demand long shelf life. Therefore, the development of supercapacitors has huge market requirements, and long-term progress is needed for their successful advancement and commercialization. Meanwhile, supercapacitors are also facing challenges such as technical problems, establishing electrical parameter models, consistency testing, and establishing industrial standards. In this paper, the above challenges and the future development opportunities of supercapacitors are introduced in detail. This perspective will provide corresponding guidance and new directions for the development of supercapacitors.

The present article intends to capture the impact of fly ash generated from Bakreswar Thermal Power Plant (BKTPP) on Chandrabhaga River of proximate location. Impacts have been captured giving emphasis on the morphological aspects of the channel and water quality standard. Chandrabhaga River (length: 26 km) of Birbhum district covers a mostly Rarh tract composed of coarse grain laterite soil. Field measurement of morphological parameters, water and soil samples collection from nine river sites and testing in laboratory reveal the following results: (1) In very proximate location of the fly ash pond, the river bed has raised up to 10–75 cm and the rate of aggradations declined downstream; (2) textural characteristics of bed materials have altered and become finer after huge influxing of fly ash; (3) leaching of finer fly ash particles in the pore space of the sand bed and consequent clogging has started which withstand the interaction between surface and subsurface flow; (4) suspended and dissolved load has increased by 62 % in comparison with the load before over spilling of fly ash from fly ash pond; (5) due to overloaded condition, more than 12,000 m3/year of fly ash is deposited over the river bed and it can defer the graded time of that river; (6) an analysis of physico-chemical properties of the collected water samples states that some of the parameters, e.g., turbidity, TDS, BOD, COD and DO, are not only beyond drinking standard but also beyond the standard of irrigation and aquatic life, specifically fishes; (7) fly ash contamination highly reduced carp fishes on which a troop of fishermen spend their livelihood and they are now in anxiety for the viability of their livelihood.

A new calorimeter to measure specific heat of indigenously prepared granular activated carbon (AC) for application in a refrigeration system based on gas adsorption–desorption mechanism is presented. This calorimeter allows specific heat measurements in high (305.5–317.8 K) as well as low (254.6–264 K) temperature ranges. The specific heat of prepared AC on measurement using developed calorimeter has been found to be 1.062 J g−1 K−1. Preparation, instrumental analyses and influence of various physical properties of AC on its specific heat have also been discussed. Characterisation results of AC demonstrate that it can be efficiently used in such cold producing system down to refrigeration and cryogenic temperature. © 2012 Canadian Society for Chemical Engineering

Replacement of halogenated refrigerants with a suitable refrigeration system in order to prevent ozone layer depletion and minimize global warming has been a matter of research and worldwide attention for some decades. This paper presents the design and description of a single chambered experimental model for cold generation based on pressure swing adsorption mechanism with an objective to propose a feasible refrigeration system to replace halogenated refrigerants. Granular activated carbon (ACG-825-1.5) manufactured indigenously from matured coconut shell and carbon dioxide has been used as representative adsorbent–adsorbate pair. Refrigerating effect and coefficient of performance for the system have been investigated and were found to be 120.61 J/s and 3.014 respectively. The model successfully produced chilled water at 4 °C (277 K) from ambient water available at 26 °C (299 K). Details of the experimental results and adsorption–desorption isotherm for the system has been described. This work also highlights a novel method of capturing carbon dioxide by utilizing it as an adsorbate in such a refrigeration system.

Two-dimensional topological insulator bismuth selenide (Bi2Se3) nanosheets (NSs) embedded in poly-methyl methacrylate (PMMA) are employed for the first time for the resistive switching (RS) application. Hexagonal 2D Bi2Se3 NSs are synthesized by a simple solvothermal method and combine with PMMA at different weight percentages of 2D Bi2Se3. Field emission scanning electron microscopy and transmission electron microscopy along with other characterizations such as X-ray photoelectron spectroscopy and Raman spectroscopy were performed for the characterization of Bi2Se3@PMMA hybrid system. The composite was deposited on a transparent, flexible polyethylene terephthalate substrate to form Ag/Bi2Se3@PMMA/indium doped tin oxide memory cell. I-V characteristics of the device revealed a stable and non-volatile memory effect. The device shows a significantly high resistance (RHRS/RLRS) ratio, more than 103, high retention time (more than 9000 s) with high reproducibility over a large number of (105) ac cycles. From the experimental data, RS performances are explained by using a charge trapping–detrapping mechanism. Owing to the increasing interest in flexible electronics, bending tests are carried out at various bending diameters (10–30 mm) to show the mechanical robustness of the proposed device.

Laser refractive surgery for myopia increases the eye's higher-order wavefront aberrations (HOA's). However, little is known about the impact of such optical degradation on post-operative image quality (IQ) of these eyes. This study determined the relation between HOA's and IQ parameters (peak IQ, dioptric focus that maximized IQ and depth of focus) derived from psychophysical (logMAR acuity) and computational (logVSOTF) through-focus curves in 45 subjects (18 to 31 yrs) before and 1-month after refractive surgery and in 40 age-matched emmetropic controls. Computationally derived peak IQ and its best focus were negatively correlated with the RMS deviation of all HOA's (HORMS) (r≥-0.5; p0.16 for all). Increase in HOA's after refractive surgery is therefore associated with a decline in peak IQ and a persistence of this sub-standard IQ over a larger dioptric range, vis-à-vis, before surgery and in age-matched controls. This optical deterioration however does not appear to significantly alter psychophysical IQ, suggesting minimal impact of refractive surgery on the subject's ability to resolve spatial details and their tolerance to blur.

The role of cytokines in Plasmodium infection have been extensively investigated, but pro and anti inflammatory cytokines mediated imbalance during malaria immune-pathogenesis is still unrevealed. Malaria is associated with the circulating levels of Interleukin-6 (IL-6) and transforming growth factor β (TGF-β), but association between these two cytokines in immune response remains largely obscured. Using mouse model, we proposed that IL-6 and TGF-β are involved in immune regulation of dendritic cells (DC), regulatory T cells (Treg), T-helper cells (Th17) during P. berghei ANKA (PbA) infection. Association between the cytokines and the severity of malaria was established with anti-TGF-β treatment resulting in increased parasitemia and increased immunopathology, whereas; anti-IL-6 treatment delays immunopathology during PbA infection. Further, splenocytes revealed differential alteration of myeloid DC (mDC), plasmocytoid DC (pDC), Treg, Th17 cells following TGF-β and IL-6 neutralization. Interestingly anti-TGF-β reduces CD11c+CD8+ DC expression, whereas anti-IL-6 administration causes a profound increase during PbA infection in Swiss mice. We observed down regulation of TGF-β, IL-10, NFAT, Foxp3, STAT-5 SMAD-3 and upregulation of IL-6, IL-23, IL-17 and STAT-3 in splenocytes during PbA infection. The STAT activity probably plays differential role in induction of Th17 and Treg cells. Interestingly we found increase in STAT-3 and decrease in STAT-5 expression during PbA infection. This pattern of STAT indicates that possibly TGF-β and IL-6 play a crucial role in differentiation of DCs subsets and Treg/Th17 imbalance during experimental cerebral malaria (ECM).

An experiment has been carried out utilizing the activated carbon granules as an adsorbent indige-nously developed from coconut shell and carbon dioxide gas as an adsorbate in a small experimental chamber, specially designed for this purpose. Adsorption followed by removal of heat of adsorp-tion and subsequent desorption produces refrigera-tion. After a few cycles in the chamber, tempera-tures drop from 304 K to 282.5 K. Therefore, con-tinuous production of refrigeration could be achieved by a suitable mechanism. The paper describes the details of the design and fabrication of the experimental chamber, the experimental proce-dure and discusses the results obtained to assess its feasibility towards development of an alternative eco friendly refrigeration cycle for replacement of chlorofluorocarbons.

The roles of dendritic cells (DCs) in mediating immunity against Plasmodium infection have been extensively investigated, but immune response during pathogenesis of malaria is still poorly understood. In the present study, we compared the splenic DCs phenotype and function during P. berghei ANKA (PbA) or P. yoelii (P. yoelii) infection in Swiss mice. We observed that PbA-infected mice developed more myeloid and mature DCs capable of secreting IL-12, while P. yoelii-infected mice had more plasmacytoid and immature DCs secreting higher levels of IL-10. Expression of FoxP3, IL-17, TGF-β and IL-6 were also different between these two infections. Thus, these results suggest that the phenotypic and functional subsets of splenic DCs are key factors for regulating immune responses to PbA and P. yoelii infections.