The interplay between spatial and heliconical orientational order in twist-bend nematic materials.

The helical pitch formed by organic molecules, such as the α-helix of proteins, usually requires hydrogen bonding between chiral units and long-range positional order. It was recently found that certain liquid crystal oligomers can have a twist-bend nematic (NTB) phase with nanoscale heliconical structure without hydrogen bonding, molecular chirality or positional order. To understand the nature of this unique structure, here we present hard and resonant tender X-ray scattering studies of two novel sulfur containing dimer materials. We simultaneously measure the temperature dependences of the helical pitch and the correlation length of both the helical and positional order. In addition to an unexpected strong variation of the pitch with the length of the spacer connecting the monomer units, we find that at the transition to the NTB phase the positional correlation length drops. The helical structure was found not only in the NTB phase but observed even in the upper range of a smectic phase that forms just below the NTB state. The coexistence of smectic layering and the heliconical order indicates a layered (SmATB) phase wherein the rigid units of the dimers are tilted with respect to the smectic layer normal in order to accommodate the bent conformation of the dimers and the tilt direction rotates along the heliconical axis.

Water quality assessment of the Ganges River during COVID-19 lockdown.

Ganges River water quality was assessed to record the changes due to the nation-wide pandemic lockdown. Satellite-based (Sentinel-2) water quality analysis before and during lockdown was performed for seven selected locations spread across the entire stretch of the Ganges (Rishikesh-Dimond Harbour). Results revealed that due to the lockdown, the water quality of the Ganges improved with reference to specific water quality parameters, but the improvements were region specific. Along the entire stretch of Ganges, only the Haridwar site showed improvement to an extent of being potable as per the threshold set by the Central Pollution Control Board, New Delhi, India. A 55% decline in turbidity at that site during the lockdown was attributed to the abrupt halt in pilgrimage activities. Absorption by chromophoric dissolved organic matter which is an indicator of organic pollution declined all along the Ganges stretch with a maximum decline at the downstream location of Diamond Harbour. Restricted discharge of industrial effluent, urban pollution, sewage from hotels, lodges, and spiritual dwellings along the Ganges are some of the reasons behind such declines. No significant change in the geographic trend of chlorophyll-a was observed. The findings of this study highlight the importance of regular monitoring of the changes in the Ganges water quality using Sentinel-2 data to further isolate the anthropogenic impact, as India continues the phase-wise opening amidst the pandemic.

Impact of conventional retting of jute (Corchorus spp.) on the environmental quality of water: a case study.

Production of quality jute fibre primarily depends on the retting process of jute. However, the quality of retting water is of great concern because of the scarcity of available water bodies for retting. A study conducted on physico-chemical and microbiological changes in retting water (pre- and post-retting) from four intensively jute-growing districts namely Nadia, North 24 Parganas, Hooghly and South Dinajpur of West Bengal, India, during jute retting. The post-retting water samples recorded lower pH (6.22 to 7.08) and higher EC (electrical conductivity) (0.509 to 0.850 ds/m) compared with pre-retting water samples (pH 6.63 to 7.44; EC 0.197 to 0.330 ds/m) collected from all the four districts under study. The biological oxygen demand (BOD) and chemical oxygen demand (COD) increased several folds in the post-retting water samples indicating very high microbial growth and activities and depleted oxygen level compared with pre-retting water. The Ca + Mg (calcium + magnesium) content in pre-retting water was high (24.15 to 36.60 ppm) which raised further (61.30 to 103.67 ppm) in post-retting water, while the bicarbonate content also increased and ranged between 2.72 and 6.81 me/l in post-retting water compared with its status in pre-retting water (1.30 to 3.15 me/l). The post-retting water was found to be a rich source of nutrients like nitrogen (N), phosphorus (P), iron (Fe), manganese (Mn), zinc (Zn) and copper (Cu) which increased substantially because of jute retting as compared with their status in pre-retting water. The population of pectinolytic, xylanolytic, cellulolytic and ligninolytic bacterial cfu (colony forming unit) increased by 1.5 times in post-retting water as compared with pre-retting water, because these specific bacterial population were involved in the degradation of pectin, xylan, cellulose and lignin during retting of jute. Thus, post-retting water can be judiciously used as a potent source of primary, secondary and micronutrients for succeeding crops besides having higher BOD and COD as a result of higher microbial growth related to jute retting.

Thiophene Appended Dual Fluorescent Sensor for Detection of Hg2+ and Cysteamine.

An efficient and highly selective pyrene-thiophene conjugate has been reported as a dual sensor for Hg2+ and cysteamine (an important drug for genetic disorder). The sensor displays a turn-on fluorescence response towards Hg2+ in a 2:1 stoichiometric ratio via excimer formation with a detection limit as low as of 30.6 nM. The excimer emission upon binding with Hg2+ has been rationalized by experimental as well as theoritical studies. Moreover, the [probe-Hg2+] adduct functions as an efficient sensor for cysteamine. This sensing process happens via the extraction of Hg2+ from the adduct. In this paper, change in emission properties of the receptor with varying pH and water content has also been explained. The sensing abilities of the sensor were examined in real water sample analysis. Therefore, the sensor can be used as an efficient and reusable fluorescent sensor for recognition of Hg2+ in water.

Association of Amelogenin with High Caries Experience in Indian Children.

OBJECTIVE: The purpose of this study was to identify alterations in amelogenin gene that are associated with dental caries susceptibility and to develop a non-invasive early screening test for caries risk. STUDY DESIGN: 60 individuals were selected for the study based on the inclusion and exclusion criteria and were divided into two groups based on DMFT score. DMFT was scored according to World Health Organization guidelines. Saliva obtained from all participants was stored in Indogenix DNA Self-Collection kits at 4°C. DNA was extracted according to the manufacturer's instructions. Once the entire DNA was isolated from each sample it was put forward for PCR amplification. The amplified amelogenin gene was then run on 2% agarose gel stained with ethidium bromide. The amplified gene was processed by SSCP technique to find out the altered bands and then subjected to DNA sequencing for identification of alterations in the amino acid sequence of amelogenin gene. RESULTS: The sequencing data showed the presence of mutation. Samples showing mutation (43.3%) showed high correlation with caries (80.7%) experience which was statistically significant. CONCLUSION: Understanding the genetics of dental caries susceptibility will provide new insights into the caries process in individuals and will facilitate the development of targeted preventive strategies.

Frequency of Hyponatremia in Adults with Acute Bacterial Meningitis.

Bacterial meningitis is a life-threatening disease. Bacterial meningitis patients are prone to develop acute hyponatremia. In the central nervous system infection hyponatremia could be due to the Syndrome of Inappropriate Anti Diuretic Hormone secretion. The frequency of hyponatremia in adults with acute bacterial meningitis patients was seen in this study. This cross-sectional study was conducted in the Internal Medicine Department of Mymensingh Medical College Hospital, Mymensingh, Bangladesh from February 2016 to July 2016. A total of 50 patients were enrolled in this study by purposive sampling. Among 50 acute bacterial meningitis patients, 33 (66%) were diagnosed as hyponatremic state. The mean serum sodium level of 33 hyponatremic bacterial meningitis cases was 130.66±2.95 mmol/L. Most of the cases (78.79%) were mild hyponatremic state (130 mmol/L-135 mmol/L) whereas 18.18% were revealed as moderate hyponatremia (125 mmol/L-129 mmol/L). Only 3.03% of cases were presented as severe cases (≤124 mmol/L). The result revealed that a large number of patients with acute bacterial meningitis were suffering from hyponatremia and in the majority of cases were mildly hyponatremic.

Hip fracture patients in India have vitamin D deficiency and secondary hyperparathyroidism.

SUMMARY: This study evaluated the parameters of bone mineral homeostasis including 25(OH)D and PTH in 90 Indian patients with hip fracture and 90 controls. Hypovitaminosis D, secondary hyperparathyroidism, and biochemical osteomalacia was present in 77, 69, and 50 % patients, respectively, significantly higher compared to controls. Vitamin D deficiency is an important risk factor for hip fracture. INTRODUCTION: The prevalence of vitamin D deficiency is not well known in hip fracture patients from India. Therefore, the present study was conducted to evaluate the parameters of bone mineral homeostasis including 25(OH)D and intact PTH in hip fracture from North India. METHODS: Ninety consecutive patients with hip fracture and similar number of age- and sex-matched controls were enrolled in the study. The fasting venous samples were analyzed for 25-hydroxyvitamin D (25-OHD), intact parathyroid hormone (PTH), alkaline phosphatase (ALP), calcium, and phosphorus. Vitamin D deficiency was defined as serum 25-OHD of <20 ng/dl. RESULTS: The mean age of hip fracture subjects was 65.9 ± 12.6 which was comparable in men and women. Majority of study subjects were women (70 women and 20 men). The serum 25(OH)D and calcium levels were significantly lower, whereas the intact PTH and ALP levels were significantly higher in patients compared to controls. There was significant negative correlation between serum 25(OH)D and PTH. In the hip fracture group, 76.7 % of the subjects had vitamin D deficiency, and 68.9 % had secondary hyperparathyroidism. In the control group, vitamin D deficiency and elevated PTH levels were seen in 32.3 and 42.2 %, respectively. CONCLUSION: About three fourths of hip fracture patients have vitamin D deficiency, and two thirds have secondary hyperparathyroidism. Therefore, the serum 25-OHD level may be a useful index for the assessment of risk of hip fracture in India.

A pyrene-based simple but highly selective fluorescence sensor for Cu(2+) ions via a static excimer mechanism.

A pyrene-based simple fluorosensor has been synthesized by a one step process. It exhibited high selectivity towards Cu(2+) ions via fluorescence enhancement of monomer and excimer emission. The origin of excimer formation was examined and established to be of static in nature from the study of absorption and excitation spectra. The observed monomer and excimer emission in the presence and absence of Cu(2+) ion with varying pH was studied and provided probable justification. The effect of varying portions of water content in solvent on the sensor molecule was also examined. The sensor found its proper application in finding accurate and trace amount of Cu(2+) ions present in drinking water samples from various sources. The detection limit of the current sensor was found to be 4 × 10(-8) M.

Atypical Presentations of Childhood Simple Partial Seizures: a Case Series.

Childhood epilepsy can masquerade as a variety of psychiatric disorders or behavioural abnormalities. Differentiating between simple partial seizure and psychiatric disorders remains a challenge. We report on three children with simple partial seizure, each presented atypically with migraine, tingling sensations, and/or crying spells. When dealing with atypical symptomatology, clinicians should utilise a multidirectional, rather than unidirectional, diagnostic approach when making their diagnosis.

Paediatric aesthetic dentistry: a review.

AIM: A number of conditions can lead to aesthetically unacceptable dentitions like dental caries, discoloration, trauma, early loss of teeth, misalignment and any abnormality of shape and size. Today we have a large number of solutions available for aesthetic problems in paediatric dentistry. But the biggest dilemma is: How to choose what is best for a particular patient and that situation? Through this review we try to precisely highlight the various options for aesthetic restorations along with their indications, advantages and disadvantages. METHODS: A search and analysis of international works on aesthetics in paediatric dentistry is presented. RESULTS: A considerable number of studies have shown that people are more concerned about missing anterior teeth and their replacement than about posterior ones as aesthetics seems to be more important than function. CONCLUSION: Dental caries, although not life threatening, causes nagging pain and physical as well as psychological discomfort. Nevertheless, it is clear that the condition is complex and multifactorial and hence it is important to review the various approaches available to restore the lost aesthetics.

Applicability of Demirjian's method of age assessment in a North Indian female population.

AIM: This study was conducted to determine whether the standards of dental maturation given by Demirjian et al. are applicable to North Indian children and to assess the relationship between dental age and chronological age. METHODS: In this study OPGs of 100 females of 8-14 years were taken, and dental age was calculated according to the Demirjian method. Chronological age was recorded and compared to dental age. STATISTICAL ANALYSIS: Collected data was statistically analysed. Pearson's correlation coefficient was used to correlate the dental and chronological age of the 100 girls. The statistical analysis was done by using SPSS version 10.0 software (SPSS Inc., Chicago IL). For all tests the p-value of <0.05 was considered for statistical significance. RESULTS: A strong correlation was found between chronological and dental ages. CONCLUSION: In the present pilot work it was concluded that the Demirjian method of dental age assessment showed high accuracy when applied to North Indian paediatric population.

Do bicarbonate-based solutions for continuous renal replacement therapy offer better control of metabolic acidosis than lactate-containing fluids?

INTRODUCTION: Evidence that bicarbonate haemofiltration and dialysate fluids are superior to lactate in patients with acute kidney injury treated by continuous renal replacement therapy (CRRT) remains controversial. METHODS: We prospectively audited acid-base during the first 48 h of CRRT in 62 patients, using bicarbonate and lactate fluids. RESULTS: Baseline lactate was greater in the bicarbonate group (4.76 ± 0.77 vs. 2.92 ± 0.5 mmol/l, p < 0.01), but pH, bicarbonate, chloride and base excess were similar. Lactate fell significantly in the bicarbonate group to 2.88 ± 0.3 mmol/l at 24 h and 2.39 ± 0.2 mmol/l at 48 h, but not in the lactate group. Base excess improved more with bicarbonate, median increase in the first 24 h was 51.6% (29.1-96.9) versus 18.5% (-5 to 55) with lactate and 74.2% (38.5-123) versus 36.1% (-3.6 to 68), p < 0.05 at 48 h. However, there were no significant differences in bicarbonate, chloride, pH, blood pressure and vasopressor requirements. 13.3% of patients were switched from lactate to bicarbonate fluids due to failure to correct acidosis. Subgroup analysis of 19 patients with liver failure showed similar results. CONCLUSION: Bicarbonate fluids led to a more rapid fall in lactate and greater improvement in base excess during CRRT, but not overall control of acidosis.

Dental pulp stem cells from primary teeth quality analysis: laboratory procedures.

OBJECTIVES: To present details of isolation, processing and differentiation of stem cells from inflamed dental pulp of primary teeth. MATERIALS AND METHODS: Tissue sample was collected from teeth indicated for a single visit pulp therapy. Samples were transported and processed in the laboratory which included culturing of cells, isolation and in vitro differentiation into multiple lineages. The results for the analysis of various cell surface markers used for dental pulp were compared with bone marrow. RESULTS: There was no statistically significant difference found in the expression of various surface markers between dental pulp and bone marrow. The stem cells from dental pulp were differentiated into multiple lineages. CONCLUSION: Isolation of cells from oral tissues is technique sensitive.

The Pattern of Lipid Profile in Patients with Chronic Kidney Disease.

Dyslipidemia is a common problem in chronic kidney disease patients. Dyslipidemia in chronic kidney disease patients has been known to be a major risk factor of their cardiovascular disease and may contribute to progressive renal dysfunction. The result of the study might be of interest in improving preventive strategies and in management of dyslipidemia in chronic kidney disease patients. This cross sectional study was conducted to evaluate changes in lipid profile in patients with chronic kidney disease stage-3 to stage-5 patients and to correlate the biochemical abnormalities with progression of the disease in Mymensingh Medical College Hospital, Bangladesh from October, 2016 to April, 2017. In this study 200 patients were including and subjected to do complete blood count, erythrocyte sedimentation rate, random blood sugar, routine examination of urine, serum creatinine and fasting lipid profile. Two hundred (200) patients (134 males, 66 females) with the mean age were 50.5±12.43 years. 44.5% patients were in CKD stage-5, 37.5% patients were in CKD stage-4, 18% patients were in CKD stage-3. Mean value of Triglyceride (TG) was 194±47.20. Eighty nine percent (89%) patient had hyper-triglyceridemia and 11% had normal triglyceride level. It was statistically significant increased in triglyceride level (p<0.05). Mean value of High density lipoprotein cholesterol (HDL-C) was 34±6.10. Low HDL-C had in 87.5% patients, normal in 12.5% patients and was statistically significant reduction in HDL-C level (p<0.05). Low Density Lipoprotein cholesterol (LDL-C) mean was 113±35.6. High level of LDL-C had optimal/or near optimal in 47% patients, 39% patients had borderline high and 14% patients had that was not statistically significant (p>0.10). Total cholesterol (TC) mean was 212±45.3. In 38% patients had within desirable level, 62% patients had high level of Total cholesterol (TC). It was not statistically significant change (p>0.01).

Near miss maternal morbidity and maternal mortality at Kathmandu Medical College Teaching Hospital.

BACKGROUND: Maternal mortality traditionally has been the indicator of maternal health all over the world. More recently review of the cases with near miss obstetric events has been found to be useful to investigate maternal mortality. Cases of near- miss are those in which women present with potentially fatal complication during pregnancy, delivery or the puerperium, and survives merely by chance or by good hospital care. OBJECTIVES: The objective of this study is to determine the prevalence and nature of near miss obstetric cases and maternal deaths at Kathmandu Medical College Teaching Hospital. MATERIAL AND METHODS: This was a descriptive study done for the period of 24 months (1 January 2008 to 31 December 2009). Cases of severe obstetric morbidity were identified during daily morning meetings. All the cases were followed during their hospital stay till their discharge or death. Five factor scoring system was used to identify the near miss cases from all the severe obstetric morbidity. For each case of maternal death, data were collected from records of maternal death audit. RESULTS: During the study period, 1562 women delivered at the institution and 36 women were identified as near-miss obstetrical cases. The prevalence of near miss case in this study was 2.3%. Five maternal deaths occurred during this period, resulting in a ratio of maternal death of 324 maternal deaths per 100,000 live births. Of the five maternal deaths three were due to pregnancy complicated with hepatitis E infection, one each due to Eclampsia and amniotic fluid embolism. Fifteen cases of near miss were due to haemorrhage (41.66%) and hypertensive disorder of the pregnancy was the cause in 10 (27.77%). Dystocia was the cause in 1(2.77%) case and infections in 7(19.4%) cases. Rare causes like anaesthetic complications were the cause in one case and dilated cardiomyopathy was the cause in two cases. CONCLUSION: The major causes of near-miss cases were similar to the causes of maternal mortality of Nepal. Need for the development of an effective audit system for maternal care which includes both near-miss obstetric morbidity and mortality is felt.

Heterogeneous precipitation mediated heterogeneous nanostructure enhances strength-ductility synergy in severely cryo-rolled and annealed CoCrFeNi2.1Nb0.2 high entropy alloy.

Possibilities of enhancing mechanical properties of brittle intermetallic containing high entropy alloys (HEAs) using novel processing and microstructural design strategies were investigated in the present work. For this purpose, homogenized CoCrFeNi2.1Nb0.2 HEA consisting of FCC matrix and complex Laves phase particles was successfully processed by severe cold- or cryo-rolling to 90% reduction in thickness followed by annealing (800 °C/1 hour(h)). As compared to cold-rolling, cryo-rolling resulted in a finer lamellar nanostructure and decidedly greater fragmentation of the Laves phase. Upon annealing, the cold-rolled HEA showed a recrystallized FCC matrix dispersed with D019 structured ε nano-precipitates. In contrast, the finer nanostructure and greater driving force for accelerated precipitation of profuse nano-precipitates at the early stages of annealing inhibited recrystallization in the cryo-rolled HEA and resulted in the formation of heterogeneous microstructure consisting of retained deformed and recrystallized regions. The novel heterogeneous microstructure of the cryo-rolled and annealed HEA resulted in a remarkable enhancement in strength-ductility synergy. The present results indicated that cryo-rolling could be used as an innovative processing strategy for tailoring heterogeneous microstructure and achieving novel mechanical properties.

Frequency and Risk Factors of Erectile Dysfunction among Bangladeshi Adult Men with Type 2 Diabetes Mellitus.

Various forms of sexual dysfunction occur in men with diabetes mellitus (DM) including disorders of libido, ejaculatory problems, and erectile dysfunction (ED). This cross sectional study was conducted in a tertiary hospital of Bangladesh from December 2017 to May 2018 to find out the frequency and risk factors of ED in subjects with type 2 DM (T2DM). One hundred fifty (150) consecutive male patients with T2DM attending the Endocrinology outpatient department (OPD) of the hospital during the study period were evaluated for the presence of ED by using the International Index of Erectile Function-5 (IIEF-5) questionnaire; their socio-demographic, anthropometric, and clinical data were also recorded. Glycemic status was assessed by measurement of fasting plasma glucose (FPG) and HbA1c. Morning serum testosterone was measured in all. Among 150 subjects 68(45.3%) had ED; ED was mild in 14.7%, mild to moderate in 18.0%, moderate in 6.0% whereas severe ED was present in 6.7% of the subjects. The subjects with ED had higher mean age, longer duration of DM, higher body mass index (BMI), higher HbA1c, higher FPG, higher serum creatinine, and lower serum testosterone level than those without ED. Study subjects in the higher age group and higher duration of DM had higher frequencies of ED. IIEF-5 score showed significant negative correlation with age, duration of DM, HbA1c, fasting plasma glucose, serum creatinine and significant positive correlation with serum testosterone. In logistic regression analysis, duration of DM and serum testosterone were found be independent predictors of ED. Frequency of ED among Bangladeshi type 2 diabetic males is high; duration of DM and serum testosterone are independent predictors of ED in them.

Coenzyme Q10 ameliorates cadmium induced reproductive toxicity in male rats.

This study aimed at investigating the protective role of CoQ10 against cadmium (Cd)-induced reproductive toxicity in male rats. Adult male Wistar rats were exposed to an acute dose of Cd (25 mg/kg bwt; Cd group), Cd+CoQ10 (25 mg/kg bwt Cd+10 mg CoQ10; Cd-Q10 group) and distilled water (control) in vivo for 15 consecutive days and semen quality was assessed. A significant reduction was noted in sperm concentration, progressive motility, morphology and DNA integrity in both Cd- and Cd-Q10 groups in comparison to control indicating Cd-induced testicular lipid per oxidation (LPO) and decline in indigenous antioxidant defense system as measured by total antioxidant capacity (TAC) (p<0.05). However, simultaneous co-administration of CoQ10 along with Cd (Cd-Q10 group) was able to improve sperm concentration, motility, progressive motility, morphology, DNA integrity, and testicular TAC as well as lower LPO compared to Cd group (p<0.05). Results indicate that used dose of CoQ10 is capable of moderately ameliorating reproductive toxicity of Cd by improving semen quality and reducing testicular oxidative stress.