Factors affecting severity and prognosis of traumatic brain injury among Bangladeshi patients: An institution based cross-sectional study.

OBJECTIVE: Traumatic brain injury (TBI) proves to be an obstacle for Bangladeshi patients due to the lack of facilities and specialist doctors in regional sections of the country. This study aimed to record different attributes of Bangladeshi TBI patients over a year i.e., their injury characteristics, treatments received and understand their impacts on the severity of TBI. METHOD: This cross-sectional study was carried out among 280 TBI patients treated in a tertiary care hospital in Dhaka. The physicians determined TBI's severity and prognosis as per the Glasgow Coma Scale (GCS) and Glasgow Outcome Score (GOS) respectively. RESULTS: Most TBI patients were male (76.1%) and aged between 18 and 50 years (52.2%), as in previous studies in South Asian countries. However, the prevalence of TBI due to road traffic accidents (RTAs) was much higher (67.9%) than in the earlier studies in South Asia. Additionally, more patients suffered from severe TBI (29.3%) and moderate TBI (35.7%), and a higher percentage of patients went through surgery (56.8%) compared to previous studies. A significant association of demographic (residence) and clinical characteristics (consciousness after injury, CT scan findings and treatment type) with the severity of TBI was found in bivariate analysis. It also revealed the significant dependence of clinical characteristics (TBI etiology, post-injury consciousness, treatment type and TBI severity) on TBI prognosis. Multivariate analysis showed that patients who were unconscious after TBI and with evident brain injury observed in CT scans have a substantially higher risk of having moderate or severe TBI than mild TBI. Moreover, patients with TBI due to RTAs or falls, evident brain injury in CT scans, post-surgical seizure, and moderate or severe TBI have a significantly higher risk of getting a more unfavorable TBI prognosis than moderate disability. CONCLUSIONS: In this study, RTAs were found to be the major cause of TBI. Additionally, some variables were identified as possible determinants of TBI severity and prognosis among Bangladeshi patients. The correlation of these variables with TBI should be further studied with the hopes that steps will be taken to reduce TBI incidents and improve its management to reduce the overall burden.

Anisotropic Two-Dimensional Disordered Wigner Solid.

The interplay between the Fermi sea anisotropy, electron-electron interaction, and localization phenomena can give rise to exotic many-body phases. An exciting example is an anisotropic two-dimensional (2D) Wigner solid (WS), where electrons form an ordered array with an anisotropic lattice structure. Such a state has eluded experiments up to now as its realization is extremely demanding: First, a WS entails very low densities where the Coulomb interaction dominates over the kinetic (Fermi) energy. Attaining such low densities while keeping the disorder low is very challenging. Second, the low-density requirement has to be fulfilled in a material that hosts an anisotropic Fermi sea. Here, we report transport measurements in a clean (low-disorder) 2D electron system with anisotropic effective mass and Fermi sea. The data reveal that at extremely low electron densities, when the r_{s} parameter, the ratio of the Coulomb to the Fermi energy, exceeds ≃38, the current-voltage characteristics become strongly nonlinear at small dc biases. Several key features of the nonlinear characteristics, including their anisotropic voltage thresholds, are consistent with the formation of a disordered, anisotropic WS pinned by the ubiquitous disorder potential.

Spontaneous Valley Polarization of Itinerant Electrons.

Memory or transistor devices based on an electron's spin rather than its charge degree of freedom offer certain distinct advantages and comprise a cornerstone of spintronics. Recent years have witnessed the emergence of a new field, valleytronics, which seeks to exploit an electron's valley index rather than its spin. An important component in this quest would be the ability to control the valley index in a convenient fashion. Here we show that the valley polarization can be switched from zero to 1 by a small reduction in density, simply tuned by a gate bias, in a two-dimensional electron system. This phenomenon, which is akin to Bloch spin ferromagnetism, arises fundamentally as a result of electron-electron interaction in an itinerant, dilute electron system. Essentially, the kinetic energy favors an equal distribution of electrons over the available valleys, whereas the interaction between electrons prefers single-valley occupancy below a critical density. The gate-bias-tuned transition we observe is accompanied by a sudden, twofold change in sample resistance, making the phenomenon of interest for potential valleytronic transistor device applications. Our observation constitutes a quintessential demonstration of valleytronics in a very simple experiment.

Medical care-seeking behaviours among drowning casualties: Results from a national survey conducted in Bangladesh.

OBJECTIVE: Despite the high magnitude of drowning, medical care-seeking behaviours among drowning casualties remain unexplored in Bangladesh. This study aimed to explore this behaviour among drowning casualties in Bangladesh. METHODS: A population-based cross-sectional study was conducted using a multi-stage cluster sampling method. Data were collected using a structured questionnaire from 299,216 rural and urban residents. RESULTS: From the survey, we found 191 drowning cases: 40.84% (n = 78) were fatal and 59.16% (n = 113) were non-fatal. Among the drowning cases, 71.2% (n = 136) were referred to healthcare providers, while 62.8% (n = 120) received medical care from different health service providers. Further analysis showed that 66.6% (n = 116) of children and 26.6% (n = 4) of adults sought healthcare. As many as 78.9% (n = 120/152) of rural residents sought healthcare, as compared to 61.5% (n = 24/39) of urban residents. Among all drowning casualties, 31.7% (n = 38) received healthcare from a qualified healthcare provider, whereas 68.3% (n = 82) received it from non-qual]ified healthcare providers. About 59 (49%) casualties received care from a pharmacy and 34 (28%) from a recognised hospital. The hospital admission rate for drowning was 11.7%. About 14 (11.7%) drowning casualties were brought to hospitals in motorised or non-motorised vehicles. As many as 97 (80.8%) patients sought healthcare attention and managed to survive. CONCLUSION: A significant number of drowning casualties sought medical care from qualified and non-qualified healthcare providers. In Bangladesh, it is necessary to develop guidelines for providing medical care for drowning casualties.

Strategies for Improving the Functionality of Zeolitic Imidazolate Frameworks: Tailoring Nanoarchitectures for Functional Applications.

Zeolitic imidazolate frameworks (ZIFs), a subclass of metal-organic frameworks (MOFs) built with tetrahedral metal ions and imidazolates, offer permanent porosity and high thermal and chemical stabilities. While ZIFs possess some attractive physical and chemical properties, it remains important to enhance their functionality for practical application. Here, an overview of the extensive strategies which have been developed to improve the functionality of ZIFs is provided, including linker modifications, functional hybridization of ZIFs via the encapsulation of guest species (such as metal and metal oxide nanoparticles and biomolecules) into ZIFs, and hybridization with polymeric matrices to form mixed matrix membranes for industrial gas and liquid separations. Furthermore, the developed strategies for achieving size and shape control of ZIF nanocrystals are considered, which are important for optimizing the textural characteristics as well as the functional performance of ZIFs and their derived materials/hybrids. Moreover, the recent trends of using ZIFs as templates for the derivation of nanoporous hybrid materials, including carbon/metal, carbon/oxide, carbon/sulfide, and carbon/phosphide hybrids, are discussed. Finally, some perspectives on the potential future research directions and applications for ZIFs and ZIF-derived materials are offered.

FAST implementation in Bangladesh: high frequency of unsuspected tuberculosis justifies challenges of scale-up.

SETTING: National Institute of Diseases of the Chest and Hospital, Dhaka; Bangladesh Institute of Research and Rehabilitation in Diabetes, Endocrine and Metabolic Disorders, Dhaka; and Chittagong Chest Disease Hospital, Chittagong, Bangladesh. OBJECTIVE: To present operational data and discuss the challenges of implementing FAST (Find cases Actively, Separate safely and Treat effectively) as a tuberculosis (TB) transmission control strategy. DESIGN: FAST was implemented sequentially at three hospitals. RESULTS: Using Xpert® MTB/RIF, 733/6028 (12.2%, 95%CI 11.4-13.0) patients were diagnosed with unsuspected TB. Patients with a history of TB who were admitted with other lung diseases had more than twice the odds of being diagnosed with unsuspected TB as those with no history of TB (OR 2.6, 95%CI 2.2-3.0, P < 0.001). Unsuspected multidrug-resistant TB (MDR-TB) was diagnosed in 89/1415 patients (6.3%, 95%CI 5.1-7.7). Patients with unsuspected TB had nearly five times the odds of being diagnosed with MDR-TB than those admitted with a known TB diagnosis (OR 4.9, 95%CI 3.1-7.6, P < 0.001). Implementation challenges include staff shortages, diagnostic failure, supply-chain issues and reliance on external funding. CONCLUSION: FAST implementation revealed a high frequency of unsuspected TB in hospitalized patients in Bangladesh. Patients with a previous history of TB have an increased risk of being diagnosed with unsuspected TB. Ensuring financial resources, stakeholder engagement and laboratory capacity are important for sustainability and scalability.

Environmentally friendly power generator based on moving liquid dielectric and double layer effect.

An electrostatic power generator converts mechanical energy to electrical energy by utilising the principle of variable capacitance. This change in capacitance is usually achieved by varying the gap or overlap between two parallel metallic plates. This paper proposes a novel electrostatic micro power generator where the change in capacitance is achieved by the movement of an aqueous solution of NaCl. A significant change in capacitance is achieved due to the higher than air dielectric constant of water and the Helmholtz double layer capacitor formed by ion separation at the electrode interfaces. The proposed device has significant advantages over traditional electrostatic devices which include low bias voltage and low mechanical frequency of operation. This is critical if the proposed device is to have utility in harvesting power from the environment. A figure of merit exceeding 10000(10(8)µW)/(mm(2)HzV(2)) which is two orders of magnitude greater than previous devices, is demonstrated for a prototype operating at a bias voltage of 1.2 V and a droplet frequency of 6 Hz. Concepts are presented for large scale power harvesting.

Negative regulation of CCaMK is essential for symbiotic infection.

One of the earliest responses of legumes to symbiotic signalling is oscillation of the calcium concentration in the nucleoplasm of root epidermal cells. Integration and decoding of the calcium-spiking signal involve a calcium- and calmodulin-dependent protein kinase (CCaMK) and its phosphorylation substrates, such as CYCLOPS. Here we describe the Lotus japonicus ccamk-14 mutant that originated from a har1-1 suppressor screen. The ccamk-14 mutation causes a serine to asparagine substitution at position 337 located within the calmodulin binding site, which we determined to be an in vitro phosphorylation site in CCaMK. We show that ccamk-14 exerts cell-specific effects on symbiosis. The mutant is characterized by an increased frequency of epidermal infections and significantly compromised cortical infections by Mesorhizobium loti and also the arbuscular mycorrhiza fungus Rhizophagus irregularis. The S337 residue is conserved across angiosperm CCaMKs, and testing discrete substitutions at this site showed that it participates in a negative regulation of CCaMK activity, which is required for the cell-type-specific integration of symbiotic signalling.

Karaya root saponin exerts a hypocholesterolemic response in rats fed a high-cholesterol diet.

Different sources of saponins are known to have hypocholesterolemic activity with varying degrees of efficacy. We hypothesize that karaya root saponin would efficiently reduce cholesterol. The aim of this study is to examine the comparative hypocholesterolemic effect of karaya root saponin in rats fed a high-cholesterol diet. Sixty male Wister-Imamichi rats were divided into 5 groups of 12 rats each constituting of the following: control group, soybean saponin-supplemented group, karaya root saponin-supplemented group, quillaja saponin-supplemented group, and tea saponin-supplemented group. Compared with the control diet, both the karaya root- and quillaja saponin-supplemented diets significantly reduced (P < .05) serum cholesterol and atherogenic index. Karaya root saponin significantly increased the serum high-density lipoprotein cholesterol, high-density lipoprotein cholesterol/cholesterol ratio, and fecal cholesterol concentrations (P < .05). The triacylglycerol concentration was significantly reduced only in the quillaja saponin-supplemented rats (P < .05). All the tea, soybean, karaya root, and quillaja saponins significantly reduced low-density lipoprotein cholesterol, and the greatest reduction was observed with karaya root saponin. Highest fecal bile acid concentration was found with quillaja saponin, whereas highest liver bile acid concentration was observed with karaya root saponin-supplemented rats (P < .05). These results collectively suggest that karaya root saponin can efficiently reduce serum cholesterol concentration in rats.