Reversible open-closed conformational switching of nano-size metalloporphyrin dimers triggered by light and temperature.

The current work demonstrates the reversible control of substantial molecular motion in 'nano-sized' molecules, where two structural isomers can 'open' and 'close' their cavities in response to light or heat. The isomers differ widely in their photophysical properties, including colour, polarity, two-photon absorption and π-conjugation, and can easily be separated through column chromatography and thus have wide applicability.

Defining anthropometric thresholds (mid-arm circumference and calf circumference) in older adults residing in the community: a cross-sectional analysis using data from the population representative Longitudinal Aging Study in India (LASI DAD).

OBJECTIVES: To identify factors associated with malnutrition (undernutrition and overnutrition) and determine appropriate cut-off values for mid-arm circumference (MAC) and calf circumference (CC) among community-dwelling Indian older adults. DESIGN: Data from the first wave of harmonised diagnostic assessment of dementia for Longitudinal Ageing Study in India (LASI-DAD) were used. Various sociodemographic factors, comorbidities, geriatric syndromes, childhood financial and health status were included. Anthropometric measurements included body mass index (BMI), MAC and CC. SETTING: Nationally representative cohort study including 36 Indian states and union territories. PARTICIPANTS: 4096 older adults aged >60 years from LASI DAD. OUTCOME MEASURES: The outcome variable was BMI, categorised as low (<18.5 kg/m2), normal (18.5-22.9 kg/m2) and high (>23 kg/m2). The cut-off values of MAC and CC were derived using ROC curve with BMI as the gold standard. RESULTS: 902 (weighted percentage 20.55%) had low BMI, 1742 (44.25%) had high BMI. Undernutrition was associated with age, wealth-quintile and impaired cognition, while overnutrition was associated with higher education, urban living and comorbidities such as hypertension, diabetes and chronic heart disease. For CC, the optimal lower and upper cut-offs for males were 28.1 cm and >31.5 cm, respectively, while for females, the corresponding values were 26 cm and >29 cm. Similarly, the optimal lower and upper cut-offs for MAC in males were 23.9 cm and >26.9 cm, and for females, they were 22.5 cm and >25 cm. CONCLUSION: Our study identifies a high BMI prevalence, especially among females, individuals with higher education, urban residents and those with comorbidities. We establish gender-specific MAC and CC cut-off values with significant implications for healthcare, policy and research. Tailored interventions can address undernutrition and overnutrition in older adults, enhancing standardised nutritional assessment and well-being.

Association Between Cognitive Performance and Nutritional Status: Analysis From LASI-DAD.

Malnutrition in low- and middle-income countries causes cognitive decline and other health problems. Harmonized Diagnostic Assessment of Dementia for Longitudinal Aging Study in India (LASI DAD) is an extensive study on late-life cognition and dementia. This study examines the link between nutrition and cognitive abilities in older adults using data from the LASI DAD. We conducted descriptive statistics on nutritional parameters (body-mass index, waist-hip ratio, and Mini-Nutritional Assessment), cognitive functions, and socio-demographic variables in 2,892 adults aged ≥60 years. Cognitive domains assessed included delayed recall, orientation, language, executive function, abstract reasoning, and attention. Cognitive impairment was defined as impaired performance in two or more domains. Mean age was 69.3 ± 7.1 years, 52.9% were female, and 57.5% were illiterate. Low body-mass index (adjusted OR: 1.88, p < .001), at risk of malnutrition (adjusted OR: 1.89, p < .001) and malnourished (adjusted OR: 2.86, p < .001) on Mini-Nutritional Assessment were associated with the presence of cognitive impairment. Better cognitive performance was associated with increased body mass index (adjusted OR: 0.74, p-.03), hemoglobin (adjusted OR: 0.91, p-.006), and serum albumin (adjusted OR: 0.38, p < .001). This study shows that nutritional status assessed by anthropometric measures and blood markers is strongly linked to cognitive performance in older adults.

Production of glutathione from probiotic Bacillus amyloliquefaciens KMH10 using banana peel extract.

Glutathione, a tri-peptide (glutamate-cysteine-glycine) with the thiol group (-SH), is most efficient antioxidative agent in eukaryotic cells. The present study aimed to isolate an efficient probiotic bacterium having the potential to produce glutathione. The isolated strain Bacillus amyloliquefaciens KMH10 showed antioxidative activity (77.7 ± 2.56) and several other essential probiotic attributes. Banana peel, a waste of banana fruit, is chiefly composed of hemicellulose with various minerals and amino acids. A consortium of lignocellulolytic enzyme was used for the saccharifying banana peel to produce 65.71 g/L sugar to support the optimal glutathione production of 181 ± 4.56 mg/L; i.e., 1.6 folds higher than the control. So, the studied probiotic bacteria could be an effective resource for glutathione; therefore, the stain could be used as natural therapeutics for the prevention/treatment of different inflammation-related gastric ailments and as an effective producer of glutathione using valorized banana waste that has excellent industrial relevance.

Demonstration of Solute-specific Synergism in Binary Solvents.

The structure and solvation behavior of binary liquid mixtures of Methanol (MeOH) and N, N-Dimethylformamide (DMF) are explored by ascertaining their intermolecular interactions with either Rhodamine-B (RhB) or Rhodamine101 (Rh101) dye through steady-state absorption, emission, and two-photon induced fluorescence. Specifically, in the present investigation, we examine the strong synergistic solvation observed for the combinations of hydrogen bond donating (MeOH) and accepting (DMF) solvent pairs. Solvatochromism causes the solvatochromic probe molecules to sense increased polarity compared to their bulk counterparts. The origin of synergism was explained in terms of solute-solvent and solvent-solvent interactions in binary solvent mixtures interactions, as evidenced by probe dependence. The solvation behavior of the Methanol and DMF binary solvent mixture shows strong probe dependence, with Rh101 showing synergism while RhB does not.

Prevalence of dementia in India: National and state estimates from a nationwide study.

INTRODUCTION: Prior estimates of dementia prevalence in India were based on samples from selected communities, inadequately representing the national and state populations. METHODS: From the Longitudinal Aging Study in India (LASI) we recruited a sample of adults ages 60+ and administered a rich battery of neuropsychological tests and an informant interview in 2018 through 2020. We obtained a clinical consensus rating of dementia status for a subsample (N = 2528), fitted a logistic model for dementia status on this subsample, and then imputed dementia status for all other LASI respondents aged 60+ (N = 28,949). RESULTS: The estimated dementia prevalence for adults ages 60+ in India is 7.4%, with significant age and education gradients, sex and urban/rural differences, and cross-state variation. DISCUSSION: An estimated 8.8 million Indians older than 60 years have dementia. The burden of dementia cases is unevenly distributed across states and subpopulations and may therefore require different levels of local planning and support. HIGHLIGHTS: The estimated dementia prevalence for adults ages 60+ in India is 7.4%. About 8.8 million Indians older than 60 years live with dementia. Dementia is more prevalent among females than males and in rural than urban areas. Significant cross-state variation exists in dementia prevalence.

Deep phenotyping and genomic data from a nationally representative study on dementia in India.

The Harmonized Diagnostic Assessment of Dementia for the Longitudinal Aging Study in India (LASI-DAD) is a nationally representative in-depth study of cognitive aging and dementia. We present a publicly available dataset of harmonized cognitive measures of 4,096 adults 60 years of age and older in India, collected across 18 states and union territories. Blood samples were obtained to carry out whole blood and serum-based assays. Results are included in a venous blood specimen datafile that can be linked to the Harmonized LASI-DAD dataset. A global screening array of 960 LASI-DAD respondents is also publicly available for download, in addition to neuroimaging data on 137 LASI-DAD participants. Altogether, these datasets provide comprehensive information on older adults in India that allow researchers to further understand risk factors associated with cognitive impairment and dementia.

Antiobesity, Antihyperglycemic, and Antidepressive Potentiality of Rice Fermented Food Through Modulation of Intestinal Microbiota.

The present study has been aimed at evaluating the antiobesity, antihyperglycemic, and antidepressive potentials of Asparagus racemosus starter-based rice fermented foods. High-throughput NGS technology has revealed a number of bacterial genera in the prepared fermented rice, such as Lactobacillus (29.44%), Brevundimonas (16.21%), Stenotrophomonas (6.18%), Pseudomonas (3.11%), Bacillus (2.88%), and others (<2%). Eight-week administration of rice fermented food has increased food intake, whole-body weight, organ weight, different fat masses, serum lipid profiles, and histology of liver and adipose tissues in HFD-induced obese mice. In addition, upregulation of fatty acid oxidation and downregulation of adipocytogenesis- and lypogenesis-related genes along with the expression of their regulatory nuclear factors such as PPARα, PPARγ, PPARδ, and SREBP-1c have also been noted. Moreover, fermented food decreases fasting blood glucose level and improves glucose and insulin tolerance as well as the expression of GLUT4 receptor. Antiobesity and antihyperglycemic effects are also supported by the changes in insulin, leptin, and adiponectin hormone levels. The real-time polymerase chain reaction (RT-PCR) and denaturing gradient gel electrophoresis (DGGE) analyses have clearly demonstrated the intense colonization of Bacteroides, Lactobacillus, and Bifidobacterium, as well as the suppressed growth rate of γ- and δ-Proteobacteria and Firmicutes in the gut after fermented food intake. In the intestine, the latter group of microorganisms possibly modulate short-chain fatty acid (SCFA) levels such as acetate, butyrate, and propionate more than twofold. The impairment of memory-learning and anxiety-like obesity-associated cognitive phenotypes is mitigated significantly (p < 0.01) by fermented food as well. Thus, the formulated fermented food could be used as a natural therapeutic to alleviate obesity and its associated psychological and pathophysiological ailments.

Poly-lysinated nanoscale carbon probe for low power two-photon bioimaging.

Effective outcome from dynamic live-cell-imaging requires utilization of a probe with high emission intensity and low photobleaching. It would be preferable to achieve such properties at a low power of the applied laser to avoid any probable damage to biological cells or tissue. Most of the used small-molecule fluorophores have been reported to show significant photobleaching in a time-dependent manner and require high laser power to gain significant intensity for bioimaging. Carbon nanoparticles have recently been successfully used for cell imaging with low bleaching characteristics but require high laser power and lack optical nonlinearity at low power levels. Here, we report the preparation, characterization, and application of a Nanoscale Carbon (NC) which, on being surface decorated with crescent-shaped poly-lysine (PLNC), provides two-photon fluorescence (TPF) and low bleaching properties. PLNC was found to stain the cytoplasm of C2C12 muscle cells in the first four-hours of incubation with high TPF in the infrared range and can be useful for deep tissue imaging with further improvements.

Intense femtosecond optical pulse shaping approaches to spatiotemporal control.

For studying any event, measurement can never be enough; "control" is required. This means mere passive tracking of the event is insufficient and being able to manipulate it is necessary. To maximize this capability to exert control and manipulate, both spatial and temporal domains need to be jointly accounted for, which has remained an intractable problem at microscopic scales. Simultaneous control of dynamics and position of an observable event requires a holistic combination of spatial and temporal control principles, which gives rise to the field of spatiotemporal control. For this, we present a novel femtosecond pulse-shaping approach. We explain how to achieve spatiotemporal control by spatially manipulating the system through trapping and subsequently or simultaneously exerting temporal control using shaped femtosecond pulses. By leveraging ultrafast femtosecond lasers, the prospect of having temporal control of molecular dynamics increases, and it becomes possible to circumvent the relaxation processes at microscopic timescales. Optical trapping is an exemplary demonstration of spatial control that results in the immobilization of microscopic objects with radiation pressure from a tightly focused laser beam. Conventional single-beam optical tweezers use continuous-wave (CW) lasers for achieving spatial control through photon fluxes, but these lack temporal control knobs. We use a femtosecond high repetition rate (HRR) pulsed laser to bypass this lack of dynamical control in the time domain for optical trapping studies. From a technological viewpoint, the high photon flux requirement of stable optical tweezers necessitates femtosecond pulse shaping at HRR, which has been a barrier until the recent Megahertz pulse shaping developments. Finally, recognizing the theoretical distinction between tweezers with femtosecond pulses and CW lasers is of paramount interest. Non-linear optical (NLO) interactions must be included prima facie to understand pulsed laser tweezers in areas where they excel, like the two-photon-fluorescence-based detection. We show that our theoretical model can holistically address the common drawback of all tweezers. We are able to mitigate the effects of laser-induced heating by balancing this with femtosecond laser-induced NLO effects. An interesting side-product of HRR femtosecond-laser-induced thermal lens is the development of femtosecond thermal lens spectroscopy (FTLS) and its ability to provide sensitive molecular detection.

Preparation of rice fermented food using root of Asparagus racemosus as herbal starter and assessment of its nutrient profile.

The popularity of traditional fermented food products is based on their healthiness. The addition of a starter brings consistent, desirable, and predictable food changes with improved nutritive, functional, and sensory qualities. The addition of a mixture of plant residues as a starter or source of microbes is an age-old practice to prepare traditional fermented food and beverages, and most of the reported data on traditional foods were based on the analysis of the final product. The contribution of an individual starter component (plant residue) is not experimentally substantiated for any traditional fermented food, but this data are very essential for the formulation of an effective starter. In this study, Asparagus racemosus, which used as a common ingredient of starter for preparation of rice fermented food in the Indian sub-continent, was used as a starter for the preparation of rice fermented food under laboratory scale, and its microbial and nutrient profile was evaluated. The fermented product was a good source of lactic acid bacteria, Bifidobacterium sp., yeast, etc. The food product was acidic and enriched with lactic acid and acetic acid with titratable acidity of 0.65%. The content of protein, fat, minerals, and vitamins (water-soluble) was considerably improved. Most notably, oligosaccharide (G3-matotriose), unsaturated fatty acids (ω3, ω6, ω7, and ω9), and a pool of essential and non-essential amino acids were enriched in the newly formulated food. Thus, the herbal starter-based rice fermented food would provide important macro- and micronutrients. They could also deliver large numbers of active microorganisms for the sustainability of health. Therefore, the selected plant part conferred its suitability as an effective starter for the preparation of healthier rice-based food products.

Evaluation of nutrient profile, biochemical composition and anti-gastric ulcer potentialities of khambir, a leavened flat bread.

Khambir is a leavened staple food among the native highlanders of Western Himalaya. It is prepared by sourdough fermentation of wheat flour with yeast (YAK) or buttermilk (BAK). Both types of bread were rich in carbohydrate, protein, dietary fiber, containing less fat and gluten, and enriched with lactic acid, vitamins, and minerals. The in vitro digestibility test showed a slow glucose-controlled release potential of khambir that reflected improved content of rapidly digestible starch, slowly digestible starch, resistant starch, and predicted glycemic index. The changes of crystallinity to amorphous structures of starch, content of protein and fatty acid, and accumulation of 17 major metabolites were evaluated through FTIR and GC-MS. The extracts of khambir alleviated cold-induced gastric ulcers in the animal model as it exhibited histoprotective and anti-inflammatory activities. This study demonstrated that the traditional leavened bread khambir is nutritious and can alleviate gastric lesions related to acute mountain sickness.

Methodological considerations in designing and implementing the harmonized diagnostic assessment of dementia for longitudinal aging study in India (LASI-DAD).

The Harmonized Diagnostic Assessment of Dementia for Longitudinal Aging Study in India (LASI-DAD) is a population-representative, prospective cohort study of late-life cognition and dementia. It is part of an ongoing international research collaboration that aims to measure and understand cognitive impairment and dementia risk by collecting a set of cognitive and neuropsychological assessments and informant reports, referred to as the Harmonized Cognitive Assessment Protocol (HCAP). LASI-DAD provides nationally representative data drawn from a subsample of the ongoing Longitudinal Aging Study in India (LASI). One of LASI-DAD's distinctive features is its rich geriatric assessment, including the collection of venous blood samples and brain imaging data for a subsample of respondents. In this paper, we discuss the methodological considerations of developing and implementing the HCAP protocol in India. The lessons we learned from translating and applying the HCAP protocol in an environment where illiteracy and innumeracy are high will provide important insights to researchers interested in measuring and collecting data on late-life cognition and dementia in developing countries. We further developed an innovative blood management system that enables us to follow the collection, transportation, assay, and storage of samples. Such innovation can benefit other population surveys collecting biomarker data.

Two-Photon-Induced Fluorescence Study of Rhodamine-6G Dye in Different Sets of Binary Solvents.

This study deals with the effects of different sets of binary solvents on the Two-Photon Induced Fluorescence (TPIF), a non-linear process, of the Rhodamine-6G (Rh6G) dye, which is a well-known xanthene dye. This work examines the importance of inter-molecular interactions, which results in the modulation of the TPIF of the Rh6G. In this work, we have investigated three binary solvent mixtures representing varying polarity and intermolecular interactions. Specific solvent mixtures used are methanol-water, methanol-dimethyl formamide, and methanol-chloroform. Since the solvent polarity across these binary solvents differs, there are significant intermolecular interactions in the binary mixture solvents, which modulate the two-photon process of Rh6G when irradiated with high-intensity laser light at 780 nm. In our studies, we find that Rh6G in the MeOH-H2O binary solvent has maximum red-shift and minimum intensity as compared to other pairs of binary liquids when the volume fraction of methanol decreases due to more extensive hydrogen bonding between the two components. Additionally, at 1:1 ratio of binary mixtures, Rh6G is found to have the highest TPEACS value for methanol-chloroform binary solvent and reason for that is related to the formation of weak H-bond networks between proton donor chloroform and proton acceptor methanol.

Unraveling the molecular dependence of femtosecond laser-induced thermal lens spectroscopy in fluids.

Fluid systems exhibit thermal lens effects due to laser irradiation accompanied by convection and in contrast primarily conductive heat dissipation is observed in solids. The presence of a significant convective mode modifies the temperature gradient in fluids resulting in a deviation of the experimental results from theories that are based on pure conduction. Herein, we present a carefully designed femtosecond laser experiment that keeps the heat generation process constant in order to account for the effect of molecular properties on thermal dissipation. We derive a theoretical model that introduces and characterizes the additional convective heat transfer in thermal lens (TL) spectroscopy which explains our observed experimental results. We measured the TL signal for a series of liquid aliphatic alkanes, ranging from hexane to decane, and their comparison has proven the validity of our model. The influence of convective heat transfer on the TL signal is predicted in terms of the dimensionless Peclet number (PE). The lower values of PE for alkanes with longer carbon chains indicate that the convective flow of heat slows down substantially for larger molecules.

Elucidating optical field directed hierarchical self-assembly of homogenous versus heterogeneous nanoclusters with femtosecond optical tweezers.

Insights into the morphology of nanoclusters would facilitate the design of nano-devices with improved optical, electrical, and magnetic responses. We have utilized optical gradient forces for the directed self-assembly of colloidal clusters using high-repetition-rate femtosecond laser pulses to delineate their structure and dynamics. We have ratified our experiments with theoretical models derived from the Langevin equation and defined the valid ranges of applicability. Our femtosecond optical tweezer-based technique characterizes the in-situ formation of hierarchical self-assembled clusters of homomers as well as heteromers by analyzing the back focal plane displacement signal. This technique is able to efficiently distinguish between nano-particles in heterogeneous clusters and is in accordance with our theory. Herein, we report results from our technique, and also develop a model to describe the mechanism of such processes where corner frequency changes. We show how the corner frequency changes enables us to recognize the structure and dynamics of the coagulation of colloidal homogeneous and heterogeneous clusters in condensed media over a broad range of nanoparticle sizes. The methods described here are advantageous, as the backscatter position-sensitive detection probes the in-situ self-assembly process while other light scattering approaches are leveraged for the characterization of isolated clusters.

Thermal Lens Study of NIR Femtosecond Laser-Induced Convection in Alcohols.

We use time-resolved thermal lens (TL) experiments to examine the convective heat transfer at microscale in the first eight members of the homologous series of primary alcohols. TL measurements enable a direct study of these primary alcohols without adding any chromophore as a function of varying heat loads created via femtosecond laser pulses at 1560 nm. Convective heat transfer leads to the asymmetrical and reduced thermal gradient, which substantially weakens the TL signal. The inflection in the time profile of the TL signal of methanol at higher powers is attributed to the greater molecular convection in methanol compared to other samples. This inflection dies out with a decrease in laser power. Our results demonstrate that the convection is more prominent at higher laser powers in all samples, and it modifies the trend in the steady-state TL signal of different alcohols with pump laser power. Methanol also has the highest steady-state TL among the primary alcohol series at low laser powers. The maxima in the TL signal are shifted systematically from methanol to ethanol and then to propanol as the laser power increases. Semiempirical analysis of time-resolved TL signal by using the latest theoretical TL model enabled us to extract the coefficient of convective heat transfer in methanol at different laser powers. In addition to that, analysis of other members of alcohol series at the highest (7.3 mW) laser power shows that convection is more facile in short-chain alcohols compared to the long-chain alcohols.