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Background: Stroke burden continues to grow; ischemic subtypes share the biggest pie. Assam is one of the states with the highest burden in-terms of mortality. Aim: In Assam, we studied factors operating at different timelines concerning stroke events in 119 stroke patients to identify entry points for policy-level interventions. Material and Methods: We used the National Institute of Health Stroke Score (NIHSS) at admission to assess stroke severity and the Modified Rankin Scale and Barthel Index of activities of daily living at discharge and day 30 after onset to study the functional outcomes. Mortality data were captured until day 30 of stroke onset, and epidemiological data on risk factors and other determinants was collected using a questionnaire. Results: In our study, the majority (55.5%) of patients admitted with stroke were in the age group of 51–70 years, while 9.2% were below 40 years. Only 2.5% of cases reached the hospital within 4.5 h; about 42% had multimorbidity. Hypertension was a major risk factor along with dyslipidemia. Nearly 18% had wake-up strokes, and a similar proportion had a cerebrovascular event in the past. Those with higher NIHSS scores had a higher risk of dying, and if they survived, they had a higher risk of poor functional outcomes at day 30. Women experienced a higher proportion of mortality than men and more so during the posthospitalization period. Conclusion: The epidemiological data obtained from this study helps provide insights into some of the determinants in the pre- and post-period of the stroke event, especially in resource-limited areas; as a part of ongoing surveillance, such data can help monitor temporal trends.

Being the key resource in quantum physics, the proper quantification of coherence is of utmost importance. Amid complex-looking functionals in quantifying coherence, we set forth a simple and easy-to-evaluate approach: principal diagonal difference of coherence (CPDD), which we prove to be non-negative, self-normalized, and monotonic (under any incoherent operation). In an attempt to extend CPDD in the domain of mixed states, we propose a simple, generic expression (applicable to other pure state coherence measures as well). To validate this theory, we consider a fictitious two-qubit system (both interacting and non-interacting) and, through the laser pulse–system interaction (semi-classical approach), compare the coherence evolution of CPDD with the relative entropy of coherence (Cr⋅e) and the l1-norm of coherence (Cl1), in both pure- and mixed-state regimes. The results from both the numerical and analytical (for a two-level system) studies clearly demonstrate a better sensitivity of CPDD in the close proximity of the maximally coherent states (MCS) than Cr⋅e or Cl1. To the best of our knowledge, CPDD is the only quantifier (among all existing coherence quantifiers) that is a linear function of density-matrix elements.

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 (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.

Abstract 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.

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

Using femtosecond-pulse-induced thermal lens spectroscopy (FTLS), we report a novel method for the quality measurements of alcohol-based hand sanitizers (ABHS). To sustain its effectiveness, the ABHS must contain the recommended concentration of alcohol content. We diluted the hand sanitizer with water to reduce the quantity of alcohol in the mixture and then performed thermal measurements on it. We performed both dual-beam Z-scan and time-resolved TL measurements to identify the alcoholic content in the ABHS. The thermal lens (TL) signal of the solvent is capable of detecting any relative change in the alcohol content in the mixture. Our technique, therefore, emerges as a sensitive tool for quality testing of alcohol-based hand sanitizers.

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.

Measurements of nonlinear optical (NLO) properties of different binary mixtures having carbon disulfide (CS2) as the common component, namely CS2-acetone, CS2-cyclopentanone, CS2-toluene, and CS2-carbon tetrachloride (CCl4), are carried out by using the z-scan technique. Open-aperture z-scan (OAZS) and close-aperture z-scan (CAZS) experiments are performed to determine the nonlinear absorption coefficient (β) and nonlinear refractive index (n2) of all binary liquid mixtures at various compositions of the components by employing a pulsed, high repetition rate (HRR) femtosecond laser. Also, we were able to use the flowing liquid to measure NLO properties in the CS2-acetone binary mixture to remove the cumulative thermal effects produced due to the pulsed HRR laser light. Nonlinear refractive index (n2) values are found to be influenced by the weak dipole-induced dipole intermolecular interactions between the nonpolar CS2 and polar acetone as well as cyclopentanone of the respective binary mixtures. On the contrary n2 values are not found to be affected by the intermolecular interactions in CS2-toluene and CS2-CCl4 binary mixtures. In comparison, the nonlinear absorption coefficient (β) values are not found to be affected by the same in all different sets of binary mixtures.

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 (

The effect of the repetition rate of femtosecond laser pulses on the two-photon absorption and nonlinear refraction of pure organic liquids is presented using the conventional Z-scan technique. Such a study provides a way to determine the nature of light-matter interaction, explicitly enabling the identification of the linear versus nonlinear regimes. Based on the type of light-matter interaction, we have identified the thermal load dissipation time for the organic liquids. Our experimental results are in good agreement with the theoretically calculated decay time for the dissipation of thermal load.

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.

Background: Jaundice in Plasmodium falciparum malaria is multifactorial and its incidence varies in different regions. It is important to assess the incidence and factors associated with malarial hepatopathy as well as its complications to understand the pattern of disease presentation in order to undertake appropriate interventional measures. There is a paucity of data with regard to malarial hepatopathy and its outcome at the global level. Aim: The study was conducted to assess the pattern, spectrum of biochemical parameters and complications of hepatopathy related to P. falciparum malaria. Materials and Methods: A descriptive study was conducted in a tertiary care hospital attached to a government medical institution in Assam, India. Demographic details of the hundred patients with P. falciparum malaria, their clinical and biochemical parameters, complications and outcome were collected using a prestructured proforma. Data was compared using proportion and Chi Square test. Results: The proportion of those with malarial hepatopathy was 38% and the incidence was more in males and younger age group. The degree of hyperbilirubinemia, complications that include renal failure, shock, acute respiratory distress syndrome, hypoglycemia and mortality were significantly more among patients with hepatopathy (P<0.05). Conclusion: Malarial hepatopathy is associated with a higher incidence of complications like renal failure, shock, acute respiratory distress syndrome and hypoglycemia. Further studies are required to elucidate the factors associated with malarial hepatopathy and to prevent the complications and mortality. [ABSTRACT FROM AUTHOR]

Abstract  We present a detailed study on fluorescence enhancement by ‘stroboscopic’ illumination with light pulses having duration ranging from few milliseconds to sub-picoseconds. We show how a delicate balance between pulse width and pulse repetition rate can result in an unprecedented fluorescence enhancement that has immediate applications in fluorescence imaging. [ABSTRACT FROM AUTHOR]

Abstract  We investigate the relative photo-damage effects during one- and two-photon excitations and demonstrate that there exist fundamental differences in the damage induced by a high repetition rate laser as compared to that of a CW laser. This difference is evident from the degree of enhanced fluorescence intensity achieved by blanking the excitation with an optical chopper. Such an enhancement in fluorescence intensity provides better signal-to-noise ratio that could have immediate applications in multiphoton imaging of live specimens. [ABSTRACT FROM AUTHOR]

Selective excitation of a particular fluorophore in the presence of others demands clever design of the optical field interacting with the molecules. We describe the use of 20- to 50-GHz pulse-train excitation leading to two-photon absorption, followed by successive one-photon stimulated emission as a potential technique in the context of controlling two-photon molecular fluorescence, with applications in microscopy. [ABSTRACT FROM AUTHOR]

In multiphoton fluorescence laser-scanning microscopy, ultrafast laser pulses i.e., light pulses having pulse width 1 ps(1 ps=10−12 s) are commonly employed to circumvent the low-multiphoton absorption cross-sections of common fluorophores. Because of the broad overlapping two-photon absorption spectra of fluorophores and the large spectral bandwidth of a short pulse, simultaneous excitation of many fluorophores is common, which justifies a persistent demand for selective excitation of individual fluorophores. We describe the use of pulse-pair excitation with possibilities of controlling molecular fluorescence in laser-scanning microscopy and compare it with coherent control using pulse sequence De and Goswami, “Coherent control in multiphoton fluorescence imaging,” Proc. SPIE 7183, 71832B (2009). [ABSTRACT FROM AUTHOR]

An effective z-scan setup with a minimum thermal effect is shown for intensity-dependent measure of two-photon absorption (TPA) with high-repetition rate lasers. Use of an additional intensity modulation with an optical chopper provides enough blanking time for a high-repetition rate laser to yield equally accurate results in TPA measurements compared to a low repetition laser. Extension of this method of thermal effect management with an optical chopper to emission studies also results in good correspondence for two-photon cross-section measurements from either z-scan or two-photon fluorescence techniques. The method also significantly enhances two-photon fluorescence, which could be promising for multiphoton microscopy. [ABSTRACT FROM AUTHOR]

Background: The recent focus is on the increase in the burden of falciparum cases with a varied spectrum of presentation and outcome, especially in developing countries like India. This study was undertaken to analyze the trend and manifestations of falciparum malaria in a tertiary care hospital., Materials and Methods: This descriptive study was carried out at the Gauhati Government Medical College and Hospital from June 2006 to May 2007. The data were collected on demographic and time characteristics, clinical and laboratory findings, the outcome of disease and expressed in proportion or percentages., Results: Out of the 100 cases, around 2(nd)/3(rd) (63%) of cases were in the age group of 15-30 years and the mean age was found to be 29.51 years. About 66% of them were males. Clinical presentations included pain abdomen (42, 42%), nausea and vomiting (35, 35%), jaundice (34, 34%), oliguria (24, 24%), altered sensorium (24, 24%), breathing difficulty (10, 10%), and seizures (5, 5%). Number of cases and mortality were more with a peak in the month of May and September. Manifestations of severe falciparum malaria included hepatopathy (38%), renal failure (28%), shock (9%), acute respiratory distress syndrome (7%), hypoglycemia (3%), and severe anemia (1%). Eighty-two cases (82%) recovered and 18 cases (18%) expired., Conclusion: Falciparum malaria is more among younger adult age group and males. Complications and mortality are also more due to falciparum malaria.