Adsorption of CO2 on KOH activated carbon adsorbents: Effect of different mass ratios.

Nitrogen and oxygen enriched carbons were prepared by the cost-effective synthesis route of carbonization of polyacrylonitrile (PAN) and subsequent KOH activation for CO2 capture. The effect of four impregnation mass ratios (KOH: PAN = 1-4) and activation temperatures (600-900 °C) on the synthesized carbon adsorbent properties was explored by different analyses. The X-ray photoelectron spectroscopy (XPS) revealed the existence of basic nitrogen and oxygen functionalities on the adsorbent's surface which increases the adsorption rate for CO2 by providing its basic sites. By increasing mass ratio (KOH:PAN) from 1:1 to 3:1, the surface area increased from 1152.4 to 1884.2 m2 g-1 and the dynamic CO2 adsorption capacity also increased from 2.1 to 2.5 mmol g-1 respectively, at 30 °C (approximately ten times the adsorption capacity of untreated PAN, 0.22 mmol g-1). Physisorption and exothermic nature of the process were confirmed by the decrease in the adsorption capacity of the adsorbents with the increase in adsorption temperature. Moreover, good cyclic stability and regenerability over 5 adsorption-desorption cycles were obtained for the adsorbents. The fractional order kinetic and Temkin isotherm models fitted best with the adsorption data. A heterogeneous interaction between CO2 and the surface of adsorbents was suggested by the isosteric heat of adsorption values. Combined with the simple method for the preparation of activated carbon adsorbents, efficient CO2 adsorption and excellent regeneration make it appropriate adsorbents for post-combustion CO2 capture.

Porous carbons derived from polyethylene terephthalate (PET) waste for CO2 capture studies.

Oxygen augmented carbon adsorbent has been developed using polyethylene terephthalate (PET) waste by first carbonizing at different temperatures (500-800 °C) and then chemically activating using different ratios of KOH: PET (mass ratio 1 to 4). The textural characterization divulges the effect of activation in terms of the development of the high surface area and micropore volume of 1690 m2 g-1 and 0.78 cm3 g-1 respectively, for the optimum sample (PET-3-700). Elemental analysis of PET-3-700 illustrates the presence of 34.33% oxygen and XPS results confirmed the occurrence of oxygen moieties which enhance the basicity of the adsorbent and promote CO2 capture. The CO2 adsorption capacity of prepared carbons was determined thermogravimetrically under dynamic conditions, at different concentrations of CO2 (6-100%) and temperatures. The maximum CO2 uptake capacity of 2.31 mmol g-1 was exhibited by PET-3-700 at an adsorption temperature of 30 °C under 100% pure CO2 flow. Four adsorption-desorption cycles corroborate almost complete regenerability of the prepared adsorbent. Adsorption kinetics at all adsorption conditions was described best by fractional order kinetic model. Freundlich isotherm fit indicates the surface of adsorbent being heterogeneous and low values of isosteric heat shows physisorption behavior of the process. Negative values of thermodynamic parameters indicate exothermic and feasible nature of adsorption process.

Proteus Syndrome.

Proteus syndrome is an extremely rare disorder with a documentation of only 100 cases world over till date. This sporadic disorder involves the skeletal system, central nervous system, eyes, skin, soft tissues and vascular system. We report a case of Proteus syndrome in a 22 year male presenting with abnormally enlarged and hypertrophied feet resulting in marked physical constraints.

Recurrent diabetic ketoacidosis: a rare presenting manifestation of primary hyperparathyroidism.

We report a rare case of primary hyperparathyroidism in a young female who presented with recurrent diabetic ketoacidosis. The patient had suffered an episode of acute pancreatitis in the past. On evaluation patient was found to have primary hyperparathyroidism and after removal of left inferior parathyroid adenoma her insulin requirement decreased by twelve units.

Ratiometric fluorescent scaffold giving discrete response towards iodide ion: a combined experimental and DFT study.

A novel ratiometric fluorescent receptor (Z)-2-(4-[diethylamino]-2-hydroxybenzylideneamino) pyridine-3-carbaldehyde (3) bearing one phenolic OH and one aldehyde group as recognition sites was synthesized and characterized. The anion recognition behaviour of receptor 3 was evaluated by various spectroscopic (UV-visible, fluorescence and (1) H nuclear magnetic resonance) methods and was validated by computational studies. The receptor showed fast response time, excellent selectivity and reproducibility towards iodide ion detection among the other surveyed anions, with a binding constant of 6.12 × 10(4) M(-1) and a detection limit of 0.24 µM, thus confirming its potential applicability as a fluorescent sensor for iodide.

N-doped nano-casted carbon monolith for Pb (II) removal and photocatalytic degradation of thiamethoxam from aqueous solution.

Single rock-like N-doped carbon monolith (ND-PFCM) was successfully constructed via nanocasting method. Phenol formaldehyde resin was taken as carbon source and nitrogen was incorporated in monoliths through NaNH2 activation. The synthesized monoliths were used for the removal of Pb (II) from aqueous solution. Various characterization techniques, namely Brunauer-Emmett-Teller (BET), Raman spectroscopy, UV-visible diffuse reflectance spectra (DRS) UV-DRS, zeta potential, scanning electron microscopy (SEM), TEM (transmission electron microscopy), TGA (thermogravimetric analysis), and XPS (X-ray photoelectron spectroscopy), were utilized to characterize synthesized monolithic samples. The different parameters such as pH, adsorbent dosage, and time were enquired on the removal efficiency of monoliths toward Pb(II). ND-PFCM exhibited the highest adsorption capacity of 330.03 mg g-1 in 180 min at pH 6. This is attributed to the fact that the better texture properties and presence of nitrogen functional groups enhance the uptake of Pb (II) ions on the monolith surface. In the kinetic studies, pseudo-second-order model fitted best with the experimental data. Furthermore, the removal of thiamethoxam (TM) from aqueous solution was done by using different weight ratios of ND-PFCM under the visible light. The maximum removal efficiency of 97.35% with rate constant of 0.02085 min-1 was obtained in 160 min. Moreover, monoliths exhibited good reusability for five consecutive cycles. The findings suggest that the synthesized monoliths exhibit characteristics suitable and eco-friendly for sustainable use in water treatment applications.

Age at autism spectrum disorder diagnosis and its association with child and family characteristics in a tertiary care hospital in Malaysia.

Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder. Despite the absence of a cure, early diagnosis and intensive early intervention can improve the outcomes. However, little is known about the median age at ASD diagnosis in Malaysia or the child/family characteristics associated with early diagnosis. Therefore, this study aimed to determine the median age at ASD diagnosis among Malaysian children presenting to the country's largest public tertiary neurodevelopmental center and to investigate the possible demographic, child, and family characteristics associated with an early age at diagnosis. Data were collected between February 2017 and February 2019 from a database maintained by the child development unit of the country's largest publicly funded tertiary hospital, containing data from an ethnically diverse population. Among Malaysian children attending the clinic, the median age at ASD diagnosis was 48 months. Early autism diagnosis (<36 months of age) was associated with increased severity of social communication and interaction impairments, coexisting intellectual impairment, children from high socioeconomic status families, and children who receive joint care from their families and a maid or babysitter. The study findings highlight the socioeconomic inequalities in the country, a lack of parental awareness of early ASD signs, and the presence of cultural influences on the age at diagnosis of ASD.

Fe(III) conjugated fluorescent organic nanoparticles for ratiometric detection of tyramine in aqueous medium: A novel method to determine food quality.

A tetrapodal receptor was synthesized and was processed into fluorescent organic nanoparticles (FONs) for determination of important analytes in aqueous medium. The receptor was fully characterized using characterization techniques. Recognition behavior of FONs towards different metal ions was investigated with fluorescence spectroscopy, amongst them Fe3+ ions showed quenching behavior in the emission spectra. The Fe3+ ion complex of FONs based sensor was further tested with different biogenic amines and ratiometric response was obtained for tyramine. Fluorescence emission profile of FONs. Fe3+ ion complex showed no change in the pH in wide range; thereby increasing their utility in biological and environmental samples. Tyramine detection was linearly proportional in response with the detection limit of 377 nM.

Calix[4]arene based dipodal receptor nanohybrids for selective determination of chloride ions in aqueous media.

A chemical sensor based on p-tert butyl calix[4]arene has been synthesized and characterized using an assortment of spectroscopic techniques such as (1)H NMR, (13)C NMR, and elemental analysis. For sensor application, organic nanoparticles (N1) of 1 have been primed by implementing re-precipitation technique, which were further employed for preparing organic-inorganic hybrid (H1) by decorating N1 with gold nanoparticles. Both N1 and H1 were characterized using UV-visible, fluorescence, and DLS studies. Photo-physical changes due to anion binding with H1 were scrutinized using UV-visible absorption spectrometer and found it to promptly and selectively recognize Cl(-) ions in aqueous media. Thus, H1 can be effectively used for recognition of Cl(-) ions in aqueous media over a wide pH range, in samples of real time importance with a detection limit of 2.84×10(-9) M with a linear detection range up to 50 µM.

Retroperitoneal Haematoma in a Patient with Dengue Haemorrhagic Fever: A Rare Case Report.

Dengue Haemorrhagic Fever (DHF) has diverse manifestations ranging from asymptomatic petechial skin haemorrhages to life threatening cerebral, pulmonary, gastrointestinal and genitourinary haemorrhages. However, the association of spontaneous retroperitoneal haematomas with DHF is not well documented in literature. We report a rare case of spontaneous retroperitoneal haematoma complicating DHF.

Zinc metal complex as a sensor for simultaneous detection of fluoride and HSO4(-) ions.

A Schiff base based tripodal receptor was synthesized and complexed with a zinc metal ion (n17) using a very easy single step process. The resulting complex was fully characterized by CHN and single crystal XRD. The real time application of the complex in aqueous media was devised by preparing its organic nanoparticles (ONPs) and their sensor activity was tested with various anions by observing changes in the fluorescence profile of n17. It was observed that ONPs of n17 responded excellently for fluoride and sulfate, producing two different signals, with detection limits of 4.84 × 10(-12) M and 5.67 × 10(-9) M respectively, without having any interference from each other. The real time application of the sensor was also tested using various samples collected from various daily utility items and found to respond exceptionally well.

A highly selective fluorescent 'turn-on' chemosensor for Zn(2+) based on a benzothiazole conjugate: their applicability in live cell imaging and use of the resultant complex as a secondary sensor of CN(-).

A benzothiazole derivative linked "off-on" multi-responsive and selective chemosensor has been synthesized and evaluated for cation recognition properties. The receptor shows a high sensitivity and selectivity for Zn(2+) through a 'turn-on' fluorescence response over the other tested cations with a detection limit as low as 0.67 µM. The receptor was successfully applied for the detection of Zn(2+) in live HeLa cells. Then, the Zn(2+) complex of receptor was also used for cyanide detection and recognition.

Waist height ratio: A universal screening tool for prediction of metabolic syndrome in urban and rural population of Haryana.

AIMS: To compare waist circumference (WC), body mass index (BMI), waist hip ratio (WHR), and waist-to-height ratio (WHtR) and define an appropriate cut-off, which is most closely predictive of the non-adipose components of the IDF metabolic syndrome (MetS) definition. METHODS AND RESULTS: A total of 3,042 adults (1,693 in rural area and 1,349 in urban area) were screened for the presence of MetS according to the IDF definition. Among 3,042 adults selected as subjects, 1,518 were male and 1,524 were female. The receiver operating curve (ROC) analysis was done to determine the optimal cut-off value and the best discriminatory value of each of these anthropometric parameters to predict two or more non-obese components of metabolic syndrome. The area under ROC (AURC) for WC was superior to that for other anthropometric variables. The optimal cut-off value of WC in urban and rural males was >89 cm, which is higher than that in urban and rural females at 83 cm and 79 cm, respectively; the optimal cut-off for WHtR was >0.51 in rural females, 0.52 in rural males, and 0.53 in both urban males and females. Both parameters were found to be better than BMI and WHR. ROC and AURC values for WC were better than those for WHtR in men and women in both urban and rural areas (P = 0.0054); however, when the entire study cohort was analyzed together, irrespective of gender and place of residence, then at a value of 0.52, WHtR scored over WC as a predictor of metabolic syndrome (P = 0.001). CONCLUSION: Although the predictive value of different gender-specific WC values is clearly superior to other anthropometric measures for predicting two or more non-adipose components of MetS, a single value of WHtR irrespective of gender and the area of residence can be used as a universal screening tool for the identification of individuals at high risk of development of metabolic complications.

Prevalence of diabetes mellitus among the adult population in rural blocks of Haryana, India: a community-based study.

OBJECTIVE: The aim of this was to study the prevalence of diabetes in the rural adult population of Haryana, India. RESEARCH DESIGN AND METHODS: A total of 2606 adults aged ≥ 18 years were randomly selected from two rural blocks of Haryana State. Those without diabetes were subjected to a 75-gram oral glucose tolerance test. Demographic, socioeconomic, and anthropometric details along with blood pressure and physical activity were recorded, and their association with the prevalence of diabetes was studied. RESULTS: The prevalence of newly detected diabetes was 7.3%, whereas the overall prevalence of known and newly detected diabetes was 13.3%. Multiple logistic analysis showed a statistically significant association between the prevalence of diabetes and increasing age, waist-to-hip ratio (WHR), positive family history of diabetes, low level of physical activity, and systolic blood pressure. No significant association was observed with education level and socioeconomic status. CONCLUSIONS: The prevalence of diabetes is rising, even in the rural population of Haryana. A positive family history of diabetes, low physical activity, and high WHR are strong predictors of diabetes in tested adult rural population of Haryana.