2D nanosheets of layered double perovskites: synthesis, photostable bright orange emission and photoluminescence blinking

Lead (Pb)-free layered double perovskites (LDPs) with exciting optical properties and environmental stability have sparked attention in optoelectronics, but their high photoluminescence (PL) quantum yield and understanding of the PL blinking phenomenon at the single particle level are still elusive. Herein, we not only demonstrate a hot-injection route for the synthesis of two-dimensional (2D) ∼2-3 layer thick nanosheets (NSs) of LDP, Cs₄CdBi₂Cl₁₂ (pristine), and its partially Mn-substituted analogue [i.e., Cs₄Cd_0.6Mn_0.4Bi₂Cl₁₂ (Mn-substituted)], but also present a solvent-free mechanochemical synthesis of these samples as bulk powders. Bright and intense orange emission has been perceived for partially Mn-substituted 2D NSs with a relatively high PL quantum yield (PLQY) of ∼21%. The PL and lifetime measurements both at cryogenic (77 K) and room temperatures were employed to understand the de-excitation pathways of charge carriers. With the implementation of super-resolved fluorescence microscopy and time-resolved single particle tracking, we identified the occurrence of metastable non-radiative recombination channels in a single NS. In contrast to the rapid photo-bleaching that resulted in a PL blinking-like nature of the controlled pristine NS, the 2D NS of the Mn-substituted sample displayed negligible photo-bleaching with suppression of PL fluctuation under continuous illumination. The blinking-like nature in pristine NSs appeared due to a dynamic equilibrium flanked by the active and in-active states of metastable non-radiative channels. However, the partial substitution of Mn²⁺ stabilized the in-active state of the non-radiative channels, which increased the PLQY and suppressed PL fluctuation and photo-bleaching events in Mn-substituted NSs.

Change in women's work burden and gender norms of unpaid care work after the second wave of the COVID-19 pandemic in India

BACKGROUND

The COVID-19 pandemic and resultant lockdown has increased the burden of unpaid care work. Hence it is essential to evaluate the crisis response in change of women's work burden and gender norms of their unpaid care work and social status.

OBJECTIVE

To investigate change in women's job roles after second the wave of the COVID-19 pandemic and its effect on physical and psychological burden of work along with identification of common contributors of gendering of care work.

METHOD

Using a structured questionnaire and simple random sampling technique, the study was conducted on married women (n = 691) in West Bengal, India after the second wave of the COVID-19 pandemic.

RESULTS

Significant job loss (p = 0.014) occurred during COVID-19. Unpaid care work increased (p = 0.04) with reduction in rest hours (p = 0.002). 62.3% women felt increased burden of work. Work burden score increased with age (p = 0.003), reduction of rest (p < 0.001) and increased care work (p = 0.022). Gendering occurred due to male partner's less contribution to care work and respondents' cognitive agreement with expected gender role. Gendering of work is less in urban areas (OR = 0.379, p = 0.008) and higher income group (OR = 5.37, p = 0.026). Women faced more gendering in case of job loss (OR = 9.27, p = 0.001) or if burdened with work (OR = 3.92, P < 0.001).

CONCLUSION

The impact of employability of women on their work role during the COVID-19 outbreak has highlighted both theoretical and practical significance that opens up the scope of further studies at national and larger ethno-geographic levels.

Dynamics of Decision-Making in Medical Pluralism: A Systematic Review of Conceptual Models

PURPOSE

Plurality of treatment choice is often observed, as in many instances people choose to use both conventional and complementary and alternative medicine (CAM). The existing models of healthcare utilization or healthcare behavior do not specifically address this medical pluralism. Hence, to understand an individual's pluralistic choice of treatment, major studies describing this have been systematically reviewed in this study in order to extract the principal factors driving such choice. Also, applicability of current healthcare models is qualitatively analyzed in order to identify whether they properly explain the factors driving such pluralistic choices.

METHODOLOGY

A systemic literature review was performed of 20 studies including 6 National Surveys. The major variables included were prevalence of integrative medicine in the last 12 months, nature of pluralism, major factors driving plurality of choice and the underlying model describing such choices.

RESULTS

Mean usage of plurality was 44.48% (95% CI, 44.12-44.84%). The major drivers of plurality were enabling (access) and cognitive factors, followed by post-decision dissonance, philosophical congruence and social factors. The studies followed several established conceptual models with almost equal distribution. These major factors and the underlying treatment models were significantly dependent upon each other (Fisher's exact test; P = .025), but the cognitive and personality factors were found to be significantly exclusive (t = 2.39; P = .017).

CONCLUSION

Medical pluralism incorporates a multitude of decision factors, which are separately related to different healthcare-decision models. Among them, personality trait was observed to be an important but neglected component of existing models. From the existing studies, no single pluralism-driven integral model could be established, satisfying all the important conditions of pluralistic choice.

Soft crystal lattice and large anharmonicity facilitate the self-trapped excitonic emission in ultrathin 2D nanoplates of RbPb2Br5

Self-trapping of excitons (STE) and concomitant useful broadband emission in low-dimensional metal halides occur due to strong electron–phonon coupling, which exhibit potential applications in optoelectronics and solid-state lighting. Lattice softness and high anharmonicity in the low-dimensional structure can lead to transient structural distortion upon photoexcitation that should promote the spatial localization or trapping of charge carriers, which is essential for STE. Herein, we report the ligand-assisted reprecipitation synthesis of ultrathin (∼3.5 nm) two-dimensional (2D) metal halide, RbPb₂Br₅ nanoplates (NPLs), which demonstrate highly Stokes shifted and broadband emission covering most parts of the visible to near IR range (500–850 nm) with a long-lived photoluminescence (PL) lifetime. The excitation wavelength independent emission and emission wavelength independent excitation spectra along with the analogous PL decay kinetics of bulk and NPLs suggest the intrinsic nature of broadband emission. The experimental low sound velocity (∼1090 m s⁻¹) and associated low bulk and shear moduli (10.10 and 5.51 GPa, respectively) indicate the large anharmonicity and significantly soft lattice structure, which trigger the broadband STE emission in 2D NPLs of RbPb₂Br₅. Strong electron-longitudinal optical (LO) phonon coupling results in broadband STE emission in 2D RbPb₂Br₅ NPLs.

The presence of large anharmonicity and lattice softness in low dimensional metal halide, RbPb₂Br₅ nanoplates, trigger strong electron–phonon coupling and consequently highly Stokes shifted broadband emission originates from self-trapped excitons.

2D layered all-inorganic halide perovskites: recent trends in their structure, synthesis and properties

Recently, halide perovskites have appeared as a superior class of materials for diverse applications, mainly in optoelectronics and photovoltaics. Perovskite halides are broadly classified as hybrid organic-inorganic and all-inorganic analogues depending on the chemical nature of the A cation in the ABX3-type structure. Immense progress has already been achieved in halide perovskites focusing mainly on the hybrid equivalents and all-inorganic three-dimensional (3D) structures, however all-inorganic two-dimensional (2D) layered halide perovskites are relatively new and their nanostructures have gained significant attention in the last few years. In this minireview, we presented a discussion on the recently developed all-inorganic 2D layered halide perovskites highlighting their crystal structure, synthetic methodologies, chemical transformations, and optical properties. We have demonstrated a significant number of examples of Pb-free 2D halide perovskite nanostructures. Strategies for the shape-controlled synthesis of nanostructures and their excitonic properties are discussed in detail. Thermal conductivity and thermoelectric properties are emphasized along with the magnetic properties of layered transition-metal based perovskites. We have also mentioned the recent examples of all-inorganic 2D halide perovskites as photocatalysts for solar-driven CO2 reduction. Finally, we have concluded the article with an outlook for the further progress in 2D all-inorganic halide perovskites toward the structural diversity and prospective new applications.

Factors determining choice of complementary and alternative medicine in acute and chronic diseases

Background Systematic analysis of the determinants of choice of a treatment modality aids to the understanding of decision process of healthcare utilization. The revealed preference of a single modality may differ according to the nature of disease. Existing studies have not integrated possible causal factors in a model with respect to diseases. This study identifies major determinants and formulates their integral effect on choice of a particular modality on acute and chronic diseases in accordance to socio-behavioural model. Methodology A cross-sectional study on 300 samples using a 30-point questionnaire, developed in Likert scale and dichotomous scale. Possible determinants are tested on choice of CAM in case of acute disease and of chronic disease separately. Results Revealed single modality treatment preference (of CAM) varies widely between acute disease (13%) and chronic disease (58.67%). Bivariate associations are significant for gender (For, overall CAM preference, p=0.001, acute disease, p<0.001, chronic disease, p=0.024), Disease burden (overall and chronic: p<0.001, acute: p=0.008) and previous CAM usage (overall and chronic: p<0.001, acute: p=0.016). Social factor individually has significant influence on choosing CAM both acute (OR=1.096, p<0.001) and chronic disease (OR=1.036, p<0.001). Ideation of philosophical need factor, guided by philosophical congruence with CAM (OR=1.047, p<0.001) is a novel finding of this study. While with multiple logistic regression male gender (p=0.03), social factor (p<0.001), perception of CAM efficacy (p=0.02) and negative ideation about CAM cost-effectiveness (p=0.002) are found to be important in Acute disease; choosing CAM in chronic disease is guided by female gender (p=0.001), making decision in-group (p=0.001), low disease burden (p<0.001), philosophical need factor (p=0.001), and perception of CAM efficacy (p<0.001). Conclusion Demographic, social, cognitive and philosophical factors are important determinants of choosing CAM as a treatment modality over conventional medicine, but they act differently on CAM preference in acute and chronic diseases.

Synthesis and Localized Photoluminescence Blinking of Lead-Free 2D Nanostructures of Cs3 Bi2 I6 Cl3 Perovskite

Two-dimensional (2D) lead-free halide perovskites have generated enormous perception in the field of optoelectronics due to their fascinating optical properties. However, an in-depth understanding on their shape-controlled charge-carrier recombination dynamics is still lacking, which could be resolved by exploring the photoluminescence (PL) blinking behaviour at the single-particle level. Herein, we demonstrate, for the first time, the synthesis of nanocrystals (NCs) and 2D nanosheets (NSs) of layered mixed halide, Cs₃ Bi₂ I₆ Cl₃ , by solution-based method. We applied fluorescence microscopy and super-resolution optical imaging at single-particle level to investigate their morphology-dependent PL properties. Narrow emission line widths and passivation of non-radiative defects were evidenced for 2D layered nanostructures, whereas the activation of shallow trap states was recognized at 77 K. Interestingly, individual NCs were found to display temporal intermittency (blinking) in PL emission. On the other hand, NS showed temporal PL intensity fluctuations within localized domains of the crystal. In addition, super-resolution optical image of the NS from localization-based method showed spatial inhomogeneity of the PL intensity within perovskite crystal.

Spectroscopic and computational insights into the ion-solvent interactions in hydrated aprotic and protic ionic liquids

Ionic liquids (ILs) and their aqueous solutions are emerging media for solving and manipulating biochemical molecules such as proteins. Unleashing the full potential however requires a detailed mechanistic understanding of how suitable protic and aprotic ILs behave in the presence of water in the first place. The present work aims at making an important step by performing a combined experimental and computational study of two selected ILs and their mixtures with water: the aprotic cholinium propionate ([Chl][Pro]) and the protic N-methyl-2-pyrrolidonium propionate ([NMP][Pro]). IR and Raman spectroscopy reveal stronger ion-solvent interactions in [Chl][Pro]-H₂O systems compared to [NMP][Pro]-H₂O mixtures. This can be explained by the tightly packed ion-pair associations in [NMP][Pro] comprising the protic -N⁺-H counterpart, which allows the establishment of highly directional and strong interionic hydrogen bonds. The spectral decomposition of the O-D stretching band into three sub-peaks showed that the protic [NMP][Pro] favors the self-association of water molecules. On the other hand, the predominant fraction of water-anion/cation aggregates exists in aprotic [Chl][Pro]. These hydrated systems can be envisaged using quantum-chemical calculations in the following way: H₂O[Chl]⁺H₂O[Pro]^-H₂O and H₂O[NMP]⁺[Pro]^-H₂O, which implied preferable solvent-shared ion-pair (SIP) configurations for [Chl][Pro]-H₂O systems, whereas the contact ion-pair (CIP) state prevails for the [NMP][Pro]-H₂O systems. The latter holds even in the water-rich regime. In future work, these findings will be the basis for an understanding of the underlying principles that govern the interactions of ions with bio-molecules in aqueous solutions.

Impact of cesium in methylammonium lead bromide perovskites: insights into the microstructures, stability and photophysical properties

The thermal and moisture instabilities of pure organic lead halide perovskites are the foremost concerns towards the commercialization of perovskite solar cells, which can be avoided by introducing an inorganic cation, such as cesium ion (Cs+) at the A-site of the perovskite crystals. In this report, the impacts of substituted Cs+ cations on the inherent properties such as microstructures, morphology, and photophysics of pure methylammonium lead bromide (MAPbBr3) perovskites have been investigated. Successful formation of mixed MA1-xCsxPbBr3 phases (with 0 ≤ x ≤ 1.0) was predicted from the theoretically calculated tolerance factor, which was further supported by the appearance of sharp diffraction peaks in X-ray diffraction (XRD) patterns without any additional peaks in the whole composition range. Substitution of Cs+ ions brings significant lattice contraction in the parent MAPbBr3 crystal due to the ion size disparity in the ionic radii between MA+ and Cs+ ions. We examine the vibrational signatures of the Raman bands related to the organic MA+ and infer the nature of interactions between the organic moiety and the surrounding inorganic cage as a function of Cs concentration. Raman spectroscopic analysis reveals structural distortion due to the altered H-bonding interaction of the N+-HBr- type between MA+ and the PbBr3- octahedral framework as a function of Cs content, which is responsible for the octahedral tilting in Cs substituted MAPbBr3. We also found hindered rotational motions of MA+ in the octahedral cage of mixed cationic systems, resulting in the orientational ordering of MA in the presence of Cs. These results certainly offer highly ordered mixed phase structures and promote superior thermal stability, as evident from the thermogravimetric analysis. The photoluminescence intensity becomes considerably enhanced at increased substitution levels, which highlights the capability of incorporated Cs+ cations in suppressing non-radiative recombination in a pure MA-based crystal, possibly related to the mitigation of trapping. The substitution of Cs+ with MAPbBr3 allows innovative strategies to improve the proficiency of tandem solar cells by modifying their structural and photophysical properties.

Molecular-Level Insights into the Microstructure of a Hydrated and Nanoconfined Deep Eutectic Solvent

Despite the recent advancements in the field of deep eutectic solvents (DESs), their high viscosity often prevents practical applications. A versatile strategy to overcome this problem is either to add a co-solvent or to confine the DES inside a nanoscaled self-organized system. This work assesses the microstructures of a hydrated and nanoconfined DES comprising benzyltripropylammonium chloride [BTPA]Cl and ethylene glycol (EG). They act as a hydrogen-bond acceptor and a donor, respectively. The hydrogen bonding between [BTPA]Cl and EG in the DES (i.e., BTEG) and the molecular states of water in the hydrated BTEG were studied by Raman spectroscopy. The results show different hydrogen-bonding associations between water-water and water-BTEG or EG molecules. In addition, we investigated the confinement effects of BTEG in a Polysorbate 80 (Tween-80)/cyclohexane reverse micellar (RM) system. The results are compared with those of an ionic liquid-encapsulated RM system. The formation, bonding characteristics, and thermal stability of the RM droplets were studied by solubilization, dynamic light scattering, rheology, and Raman spectroscopy experiments. Furthermore, it is shown that hydrogen bonding between the DES and the surfactant leads to a stable RM system. Interestingly, the viscosity of the RM system is significantly lower than that of the neat DES suggesting that DESs have a much wider practical applicability in the form of RMs.

Aggregation behaviour of biocompatible choline carboxylate ionic liquids and their interactions with biomolecules through experimental and theoretical investigations

The self-assembly of long-chain choline carboxylates accompanied by their interaction with BSA protein were investigated with focus on environmental sustainability.

Enhanced stability and water solubilizing capacity of water-in-oil microemulsions based on protic ionic liquids

In view of this limited research on pILs in microemulsions, here we study the formation and characterization of a series of pIL–water/oil microemulsions with specific questions on the effect of pILs on water uptake capacity and thermal stability of W/O microemulsions.

Eimeria species occurrence varies between geographic regions and poultry production systems and may influence parasite genetic diversity

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Multivariate analysis revealed comparable poultry clusters in north and south India.

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Eimeria species occurrence varied between system clusters.

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E. tenella occurrence across systems may underpin region-specific genetic diversity.

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E. necatrix was found to be more common in north than south India.

Coccidiosis is one of the biggest challenges faced by the global poultry industry. Recent studies have highlighted the ubiquitous distribution of all Eimeria species which can cause this disease in chickens, but intriguingly revealed a regional divide in genetic diversity and population structure for at least one species, Eimeria tenella. The drivers associated with such distinct geographic variation are unclear, but may impact on the occurrence and extent of resistance to anticoccidial drugs and future subunit vaccines. India is one of the largest poultry producers in the world and includes a transition between E. tenella populations defined by high and low genetic diversity. The aim of this study was to identify risk factors associated with the prevalence of Eimeria species defined by high and low pathogenicity in northern and southern states of India, and seek to understand factors which vary between the regions as possible drivers for differential genetic variation. Faecal samples and data relating to farm characteristics and management were collected from 107 farms from northern India and 133 farms from southern India. Faecal samples were analysed using microscopy and PCR to identify Eimeria occurrence. Multiple correspondence analysis was applied to transform correlated putative risk factors into a smaller number of synthetic uncorrelated factors. Hierarchical cluster analysis was used to identify poultry farm typologies, revealing three distinct clusters in the studied regions. The association between clusters and presence of Eimeria species was assessed by logistic regression. The study found that large-scale broiler farms in the north were at greatest risk of harbouring any Eimeria species and a larger proportion of such farms were positive for E. necatrix, the most pathogenic species. Comparison revealed a more even distribution for E. tenella across production systems in south India, but with a lower overall occurrence. Such a polarised region- and system-specific distribution may contribute to the different levels of genetic diversity observed previously in India and may influence parasite population structure across much of Asia and Africa. The findings of the study can be used to prioritise target farms to launch and optimise appropriate anticoccidial strategies for long-term control.

Decontamination of heavy metal laden sewage sludge with simultaneous solids reduction using thermophilic sulfur and ferrous oxidizing species

A possibility of using simultaneous sewage sludge digestion and metal leaching (SSDML) process at the thermophilic temperature to remove heavy metals and suspended solids from sewage sludge is explored in this study. Though thermophilic sludge digestion efficiently produces a stable sludge, its inability to remove heavy metals requires it to be used in tandem with another process like bioleaching for metal reduction. Previously, different temperature optima were known for the heterotrophs (thermophilic) responsible for the sludge digestion and the autotrophs involved in bioleaching (mesophilic), because of which the metal concentration was brought down separately in a different reactor. In our study, SSDML process was carried out at 50 °C (thermophilic) by using ferrous sulfate (batch-1) and sulfur (batch-2) as the energy source in two reactors. The concentration of volatile suspended solids reduced by >40% in both batches, while that of heavy metals zinc, copper, chromium, cadmium and nickel decreased by >50% in both batch-1 and batch-2. Lead got leached out only in batch-1. Using 16S rRNA gene-based PCR-denaturing gradient gel electrophoresis analysis, Alicyclobacillus tolerans was found to be the microorganism responsible for lowering the pH in both the reactors at thermophilic temperature. The indicator organism count was also below the maximum permissible limit making sludge suitable for agricultural use. Our results indicate that SSDML at thermophilic temperature can be effectively used for reduction of heavy metals and suspended solids from sewage sludge.

Synergistic interactions of surfactant blends in aqueous medium are reciprocated in non-polar medium with improved efficacy as a nanoreactor

Efficient soft chemical nanoreactors: a design strategy to improve the performance of a model C–C cross coupling (Heck) reaction under nanoscopic confinement of surfactant blends.

Cardiovascular health awareness and the effect of an educational intervention on school-aged children in a rural district of India

BACKGROUND AND OBJECTIVES

India is the second most populous country in the world and two-thirds of its population is less than 35 years old. This survey was conducted to assess the level of health awareness of cardiovascular disease in adolescent school-aged children 14-16 years old, with the goal of establishing school-based health education and development of heart-healthy lifestyle practices.

METHODS

A school-based survey was conducted in the rural district of West Midnapore, India between June and July of 2014. This involved a pre-evaluation of cardiovascular disease (CVD) health awareness, a short presentation on CVD, and a post-evaluation of CVD health awareness.

RESULTS

A total of 2995 students (48% response rate) from 20 schools participated in the survey. The mean age of the students in the study sample was 14.7 years, 46% were male, 53% were in the 9th grade, and the rest were in the 10th grade. After assessing students' awareness in six domains with 20 multiple-choice questions with a maximum score of 100, the mean pre-test score was 41.1 (SD±10.5) and the mean post-test score was 48.1 (SD±16.9) (p<0.001).

CONCLUSIONS

Awareness of CVD and its risk factors was far from optimal among the adolescent school-aged children in this study. A school-based educational program may help improve awareness of CVD and reduce the future disease burden in the community. The results of this study may be useful in formulating a nationwide school health program to deal with the emerging epidemic of CVD in countries such as India.

Genetic diversity within ITS-1 region of Eimeria species infecting chickens of north India

Coccidiosis, caused by apicomplexan parasites of the genus Eimeria, inflicts severe economic losses to the poultry industry around the globe. In the present study, ITS-1 based species specific nested PCR revealed prevalence of E. acervulina, E. brunetti, E. maxima, E. mitis, E. praecox, E. necatrix and E. tenella in 79.2%, 12.5%, 64.6%, 89.6%, 60.4%, 64.6% and 97.9% poultry farms of north India, respectively. The ITS-1 sequences of different Eimeria spp. from north India were generated and analyzed to establish their phylogenetic relationship. The sequence identity with available sequences ranged from 80 to 100% in E. tenella, 95 to 100% in E. acervulina, 64 to 97% in E. necatrix, 96 to 99% in E. brunetti and 97 to 98% in E. mitis. Only long ITS-1 sequences of E. maxima could be generated in the present study and it had 80-100% identity with published sequences. Two out of the four ITS-1 sequences of E. maxima had mismatches in the published nested primer sequences from Australia, while one sequence of E. necatrix had a mismatch near 3' end of both forward and reverse published nested primer sequences, warranting for the need of designing new set of degenerate primers for these two species of Eimeria. In the phylogenetic tree, all isolates of E. acervulina, E. brunetti, E. mitis, E. tenella and E. necatrix clustered in separate clades with high bootstrap value. E. maxima sequences of north Indian isolates grouped in a long form of E. maxima clade. Complete ITS-1 sequences of E. necatrix and E. mitis are reported for the first time from India. Further studies are required with more number of isolates to verify whether these differences are unique to geographical locations.

Impact of abrupt temperature increase on the performance of an anaerobic hybrid bioreactor and its intrinsic microbial community

This study aimed to analyse the effect of sudden temperature increases (in the range of 45-65 °C) on the performance and the microbial community structure of a hybrid anaerobic reactor. The reactor recovered with time after every temperature shock up to the operating temperature of 55 °C. At 55 °C, a 10 °C shock resulting in an operating temperature of 65 °C, deteriorated the reactor's performance. At this condition, both, the diversity and the relative abundance of methanogenic groups, especially of Methanosaetaceae, were significantly affected as observed by DGGE fingerprinting and quantitative PCR. In contrast, at lower temperatures (i.e., 45 and 55 °C), thermal shocks seemed to have less effect due to the presence and maintenance of thermophilic strains, which prevented system deterioration. At 65 °C, the absence of any acetoclastic methanogen is assumed to be the cause of system failure.

Genetic characterization and phylogenetic relationships based on 18S rRNA and ITS1 region of small form of canine Babesia spp. from India

Canine babesiosis is a vector borne disease caused by intra-erythrocytic apicomplexan parasites Babesia canis (large form) and Babesia gibsoni (small form), throughout the globe. Apart from few sporadic reports on the occurrence of B. gibsoni infection in dogs, no attempt has been made to characterize Babesia spp. of dogs in India. Fifteen canine blood samples, positive for small form of Babesia, collected from northern to eastern parts of India, were used for amplification of 18S rRNA gene (∼1665bp) of Babesia sp. and partial ITS1 region (∼254bp) of B. gibsoni Asian genotype. Cloning and sequencing of the amplified products of each sample was performed separately. Based on sequences and phylogenetic analysis of 18S rRNA and ITS1 sequences, 13 were considered to be B. gibsoni. These thirteen isolates shared high sequence identity with each other and with B. gibsoni Asian genotype. The other two isolates could not be assigned to any particular species because of the difference(s) in 18S rRNA sequence with B. gibsoni and closer identity with Babesiaoccultans and Babesiaorientalis. In the phylogenetic tree, all the isolates of B. gibsoni Asian genotype formed a separate major clade named as Babesia spp. sensu stricto clade with high bootstrap support. The two unnamed Babesia sp. (Malbazar and Ludhiana isolates) clustered close together with B. orientalis, Babesia sp. (Kashi 1 isolate) and B. occultans of bovines. It can be inferred from this study that 18S rRNA gene and ITS1 region are highly conserved among 13 B. gibsoni isolates from India. It is the maiden attempt of genetic characterization by sequencing of 18S rRNA gene and ITS1 region of B. gibsoni from India and is also the first record on the occurrence of an unknown Babesia sp. of dogs from south and south-east Asia.

Drying, burning and emission characteristics of beehive charcoal briquettes: an alternative household fuel of Eastern Himalayan Region

Beehive charcoal briquettes were produced from powdered charcoal in which soil was added as binder. It was found to be an eco-friendly, clean and economic alternative source of household fuel for the people of Eastern Himalayan Region. Experiments were conducted to determine natural drying behaviour, normalised burn rate, temperature profile and emission of CO, CO2, UBHC (unburnt hydrocarbons) and NO(x) of beehive briquettes prepared from 60:40; 50:50 and 40:60 ratios of charcoal and soil. It was observed that under natural drying conditions (temperature, humidity) briquettes took 433 hr to reach equilibrium moisture content of 5.56-10.29%. Page's model was found suitable to describe the drying characteristics of all three combinations. Normalised burn rate varied between 0.377-0.706% of initial mass min⁻¹. Total burning time of briquette ranged between 133-143 min. The peak temperature attained by briquettes ranged from 437 °C to 572 °C. All the briquette combinations were found suitable for cooking and space heating. Emission of CO, CO2, UBHC, NO and NO2 ranged between 68.4-107.2, 922-1359, 20.9-50.8, 0.19-0.29 and 0.34-0.64 g kg⁻¹, respectively which were less than firewood.

Comparative Studies on Performance Characteristics of CI Engine Fuelled with Neem Methyl Ester and Mahua Methyl Ester and Its Respective Blends with Diesel Fuel

In the present investigation, neem and mahua methyl ester were prepared by transesterification using potassium hydroxide as a catalyst and tested in 4-stroke single cylinder water cooled diesel engine. Tests were carried out at constant speed of 1500 rev/min at different brake mean effective pressures. A series of tests were conducted which worked at different brake mean effective pressures, OkPa, 1kPa, 2kPa, 3kPa, 4kPa, 5kPa, 6kPa and 6.5kPa. The performance and exhaust emission characteristics of the diesel engine were analyzed and compared with diesel fuel. Results showed that BTE of NME was comparable with diesel and it was noted that the BTE of N0100 is 63.11% higher than that of diesel at part load whereas it reduces 11.2% with diesel fuel at full load. In case of full load, NME showed decreasing trend with diesel fuel. BTE of diesel was 15.37% and 36.89% at part load and full load respectively. The observation indicated that BTE for MME 100 was slightly higher than diesel at part loads. The specific fuel consumption (SFC) was more for almost all blends at all loads, compared to diesel. At part load, the EGT of MME and its blends were showing similar trend to diesel fuel and at full load, the exhaust gas temperature of MME and blends were higher than diesel. Based on this study, NME could be a substitute for diesel fuel in diesel engine.

Physicochemical investigation of mixed surfactant microemulsions: water solubilization, thermodynamic properties, microstructure, and dynamics

In this contribution, we report on a systematic investigation of phase behavior and solubilization of water in water-in-heptane or decane aggregates stabilized by mixtures of polyoxyethylene (20) cetyl ether (Brij-58) and cetyltrimethylammonium bromide (CTAB) surfactants with varying compositions in conjugation with 1-pentanol (Pn) at fixed surfactant(s)/Pn ratio and temperature. Synergism in water solubilization was evidenced by the addition of CTAB to Brij-58 stabilized system in close proximity of equimolar composition in both oils. An attempt has been made to correlate composition dependent water solubilization and volume induced conductivity studies to provide insight into the solubilization mechanism of these mixed systems. Conductivity studies reveal the ascending curve in water solubilization capacity-(Brij-58:CTAB, w/w) profile as the interdroplet interaction branch indicating percolation of conductance and the descending curve is a curvature branch due to the rigidity of the interface in these systems. The microstructure of these systems as a function of surfactant composition has been determined by dynamic light scattering (DLS) and Fourier transform infrared spectroscopy (FTIR) measurements. FTIR study reveals increase and decrease in relative population of bound and bulk-like water, respectively, with increase in Brij-58:CTAB (w/w). DLS measurements showed that the droplet hydrodynamic diameter (Dh) decreases significantly with the increase in Brij-58:CTAB (w/w). Further, the interfacial composition and energetic parameters for the transfer of Pn from bulk oil to the interface were evaluated by the dilution method. Formation of temperature-insensitive microemulsions and temperature invariant droplet sizes are evidenced in the vicinity of the equimolar composition. The results are interpreted in terms of a proposed mechanism.

Detection of beet yellows virus by RT-PCR and immunocapture RT-PCR in Tetragonia expansa and Beta vulgaris

Two sensitive methods, RT-PCR with phenol-extracted RNA or Triton X-100-released RNA and immunocapture RT-PCR (IR-RT-PCR) were used for the detection of Beet yellows virus (BYV) in young and old leaves of Tetragonia expansa and sugar beet (Beta vulgaris) and in sugar beet roots. Four oligonucleotide primer pairs proved suitable for the detection of BYV. The release of BYV RNA with Triton X-100 was shown to be a very effective and easy as compared to isolation of total RNA by phenol extraction with the same or higher sensitivity of subsequent PCR. Using the Triton X-100 release of RNA and IC-RT-PCR the sensitivity of detection was so high that pg amounts of BYV RNA occurring in dilutions up to 10(-6) of saps from young Tetragonia and sugar beet leaves could be detected.

Perturbative study of classical Ablowitz-Ladik type soliton dynamics in relation to energy transport in alpha-helical proteins

Classical Ablowitz-Ladik type soliton dynamics from three closely related classical nonlinear equations is studied using a perturbative method. Model nonintegrable equations are derived by assuming nearest neighbor hopping of an exciton(vibron) in the presence of a full exciton(vibron)-phonon interaction in soft molecular chains in general and spines of alpha-helices in particular. In all cases, both trapped and moving solitons are found implying activation energy barrier for propagating solitons. Analysis further shows that staggered and nearly staggered trapped solitons will have a negative effective mass. In some models the exciton(vibron)-phonon coupling affects the hopping. For these models, when the conservation of probability is taken into account, only propagating solitons with a broad profile are found to be acceptable solutions. Of course, for the soliton to be a physically meaningful entity, total nonlinear coupling strength should exceed a critical value. On the basis of the result, a plausible modification in the mechanism for biological energy transport involving conformational change in alpha-helix is proposed. Future directions of the work are also mentioned.