Constipation

Constipation is a common gastrointestinal (GI) disorder among all age groups. Constipation can be functional or pathological comprising of many etiologies. It can also be classified as acute or chronic; mild to severe. Although in most of the cases it is benign, symptoms can significantly affect the quality of life and cost-related burden for the patient. However, chances of late diagnosis of constipation are high due to a variety of etiologies and variable presentation. Most of the times, it is a great challenge for the clinician to find out the cause of constipation. Healthy lifestyle, especially keeping regular bowel habit, drinking adequate fluid, and the use of high-fiber diet that reduces the viscosity of stool, minimizes intestinal transit time and decreases the chance of constipation. Early diagnosis and management of other underlying factors are important to give relief to the patient from the undue physical and psychological stress

The role of spatial size and orientation of electronic wavefunction in exciton dissociation at van der Waals interfaces

Organic photovoltaic (OPV) devices are environmental-friendly, lightweight, flexible and inexpensive. However, one of the setbacks for commercial application is its relative low performance in solar to electrical energy conversion compared to inorganic counterparts such as Si solar cells. Unlike typical inorganic materials in which free carriers are generated directly by the light absorption, excitons, Coulombic bound electron-hole pairs, are created upon light absorption in OPV materials. The performance of OPVs depends on how effective the bound charge transfer (CT) exciton, an exciton with its electron and hole spatially separated by the donor-acceptor interface, can dissociate to generate free charge carriers. In this thesis, the roles of the orientation of the delocalized electron wavefunction and the interfacial energy landscape in the exciton dissociation (ED) process are studied in order to understand mechanisms that control the ED efficiency. A number of donor–acceptor interfaces including organic/organic and organic/transition metal dichalcogenides (TMDs) interfaces with different molecular orientations were prepared, and exciton dynamics at these interfaces were probed. We employed time-resolved photoemission spectroscopy to measure the CT exciton dynamics, by which we were able to track the temporal evolution of the energy and the size of CT excitons. Our results on the organic-organic donor-acceptor interfaces show that the relative orientation of the delocalized electron and hole wavefunction within the CT exciton plays an important role in determining whether free carriers can be generated effectively from the CT exciton. Energy uphill, spontaneous exciton dissociation (SED) was observed on the few picosecond (ps) timescale at the zinc phthalocyanine (ZnPc)/fluorinated zinc phthalocyanine (F8ZnPc) interface with a face-on molecular orientation, at which both the electron and hole wavefunctions delocalize in the direction perpendicular to the interface. By contrast, cooling of hot CT excitons to lower energy bound CT excitons (cold excitons) was observed at the ZnPc/fullerene (C60) interface with an edge-on ZnPc orientation, at which the hole wavefunction in the CT exciton delocalizes in a direction parallel to the interface. The difference in the CT exciton dynamics suggests that free charges can be generated more effectively at the ZnPc/F8ZnPc interface with a face-on orientation. In addition, two very similar organic-TMD interfaces (ZnPc/bulk-MoS2 and ZnPc/monolayer (ML) MoS2) were studied and distinctly different CT exciton dynamics were observed. At the ZnPc/bulk-MoS2 interface, after the formation of the CT exciton, back electron transfer occurs which results in the formation of triplet excitons in the ZnPc. On the other hand, at the ZnPc/ML MoS2 interface, free carriers are generated effectively from CT excitons. This difference in the CT exciton dynamics is explained by the difference in the extent of the interfacial band bending found at the two interfaces. Overall, our study demonstrates that whether free carriers can be generated from the CT exciton depends sensitively on the local energy landscape around the interface and the electron delocalization within the CT exciton at the nanoscale. Understanding how the interfacial structure would affect the temporal evolution of the CT exciton is important for designing interfaces for effective charge generation

A Child with Severe Malaria Presenting with Acute Surgical Abdomen (Duodenal Perforation)

Plasmodium falciparum, the commonest cause of severe malaria in children, is an important cause of mortality in developing nations like Nepal. Duodenal perforation in a case of complicated malaria, although a rare entity, can occur in children. Early diagnosis, proper medical treatment, and early surgical repair can be a lifesaving measure in such cases. Here, we report a case of a 5-year-old male child with falciparum malaria complicated by a duodenal perforation that was successively managed with appropriate antimalarial drugs and early surgical repair

Generation investment and risks modeling in a deregulated electricity market

A new probabilistic model to simulate generation investment and risks applicable in a deregulated market is proposed. In this process, probabilistic production cost simulation is applied to simulate energy dispatches. Electricity prices are simulated from a modified Black-Scholes-Merton (BSM) based price simulation model. In this work, the existing BSM model is enhanced thus making it possible to simulate the demand and supply conditions in price determination. A complete investment analysis model is then developed by integrating the above two simulation processes. Using this model, generator investors can analyze the impacts on the anticipated revenue due to different plant efficiency, availabilities, bilateral contract markets and changes in demand and supply conditions. Simulated results show that the proposed model is able to analyse the viability in generation investment with much simplicity. Copyright ©1999-2011 Berkeley Electronic Pres

Constant velocity pulling and unfolding of thyroid hormone receptor by steered molecular dynamics

Unfolding pathways of T3 liganded thyroid hormone receptor (THRT3) can be studied by using the protocols of steered molecular dynamics (SMD). Theory of constant velocity pulling has been implemented to the structure of THRT3 in a neutral water-ion solution equilibrated up to 20 ns. The globular form of THRT3 is completely unfolded extending N-C termini from 38 Å to 876 Å at a constant speed of 0.1 Å/ps by means of 8.5 ns long SMD simulations. The peak force measured in the intermediate conformations is related to a burst of backbone H-bonds among a-helices and b-hairpins. With decrease in H-bonds, electrostatic energy increases by losing gradually the secondary structure and separating a and b-strands in solution. The force at the end (t > 8.5 ns) increases steeply with the large increase in bond-angle and bond-length potentials when the system becomes completely unfolded. The hydrophobic ligand binding domain (LBD) of THR-b with load bearing H-bonds protects T3 from water attack.  Even after complete unfolding of THR-b LBD, the position of T3 is not deviated more than 2.5 Å and a large number of water molecules remain in the surrounding of this domain area. This is a strong evidence for the mechanochemical stability of a receptor protein’s LBD towards hormone activated gene expressions followed by ligand binding and dissociation. BIBECHANA 17 (2020) 50-5

Constant velocity pulling and unfolding of thyroid hormone receptor by steered molecular dynamics

Unfolding pathways of T3 liganded thyroid hormone receptor (THRT3) can be studied by using the protocols of steered molecular dynamics (SMD). Theory of constant velocity pulling has been implemented to the structure of THRT3 in a neutral water-ion solution equilibrated up to 20 ns. The globular form of THRT3 is completely unfolded extending N-C termini from 38 Å to 876 Å at a constant speed of 0.1 Å/ps by means of 8.5 ns long SMD simulations. The peak force measured in the intermediate conformations is related to a burst of backbone H-bonds among a-helices and b-hairpins. With decrease in H-bonds, electrostatic energy increases by losing gradually the secondary structure and separating a and b-strands in solution. The force at the end (t > 8.5 ns) increases steeply with the large increase in bond-angle and bond-length potentials when the system becomes completely unfolded. The hydrophobic ligand binding domain (LBD) of THR-b with load bearing H-bonds protects T3 from water attack.  Even after complete unfolding of THR-b LBD, the position of T3 is not deviated more than 2.5 Å and a large number of water molecules remain in the surrounding of this domain area. This is a strong evidence for the mechanochemical stability of a receptor protein’s LBD towards hormone activated gene expressions followed by ligand binding and dissociation. BIBECHANA 17 (2020) 50-5

Pyrolyzed human hair: a review on synthesis, characterization and applications

Human hair, a common biowaste, can be pyrolyzed to prepare many kinds of functional materials. Pyrolyzed hair has been used in various forms of traditional medicine, sensor, ink, and electrolytes. This review highlights the major structural characteristics of human hair and its pyrolyzed form. It also addresses the characterization techniques used for the structure elucidation of pyrolyzed human hair as well as its potential applications. BIBECHANA 18 (1) (2021) 231-23

Pyrolyzed human hair: a review on synthesis, characterization and applications

Human hair, a common biowaste, can be pyrolyzed to prepare many kinds of functional materials. Pyrolyzed hair has been used in various forms of traditional medicine, sensor, ink, and electrolytes. This review highlights the major structural characteristics of human hair and its pyrolyzed form. It also addresses the characterization techniques used for the structure elucidation of pyrolyzed human hair as well as its potential applications. BIBECHANA 18 (1) (2021) 231-23

Pedestrian injuries in collisions with pedal cycles in the context of increased active travel: Trends in England, 2005-2015.

Introduction: Increasing levels of active travel in the population brings many public health benefits, but may also change the risks of road injury for different road users. We examined changes in rates of pedestrian injuries resulting from collisions with pedal cycles and motor vehicles in England during 2005-2015, a period of increased cycling activity, and described the gender, age distribution and locations of pedestrians injured in collisions with pedal cycles and motor vehicles. Methods: Collisions data were obtained from police STATS19 datasets. We used two measures of cycle/motor vehicle use; miles per annum, and estimated average travel time, and assessed evidence for trends towards increase over time using Poisson regression analysis. Results: There were 3414 pedestrians injured in collisions with one or more pedal cycles in England during 2005-2015, 763 of whom were killed or seriously injured (KSI). This accounted for 1.3% of the total pedestrians KSI from all vehicles. Of those KSI in collisions with cycles, 62% were female; 42% over the age of 60; 26% were on the footway or verge and 24% were on a pedestrian crossing. There was a 6% (IRR 1.056; 95% CI 1.032-1.080, p < 0.001) annual increase in the pedestrian KSI rate per billion vehicle miles cycled in England over the time span. This increase was disproportionate to the increase in cycle use measured by vehicle miles or time spent cycling. Conclusions: Increases in cycling were associated with disproportionate increases in pedestrian injuries in collisions with pedal cycles in England, although these collisions remain a very small proportion of all road injury. Increased active travel is essential for meeting a range of public health goals, but needs to be planned for with consideration for potential impact on pedestrians, particularly older citizens

Outbreak of tropical rat mite (Ornithonyssus bacoti) dermatitis in a home for disabled persons

Five mentally handicapped individuals living in a home for disabled persons in Southern Germany were seen in our outpatient department with pruritic, red papules predominantly located in groups on the upper extremities, neck, upper trunk and face. Over several weeks 40 inhabitants and 5 caretakers were affected by the same rash. Inspection of their home and the sheds nearby disclosed infestation with rat populations and mites. Finally the diagnosis of tropical rat mite dermatitis was made by the identification of the arthropod Ornithonyssus bacoti or so-called tropical rat mite. The patients were treated with topical corticosteroids and antihistamines. After elimination of the rats and disinfection of the rooms by a professional exterminator no new cases of rat mite dermatitis occurred. The tropical rat mite is an external parasite occurring on rats, mice, gerbils, hamsters and various other small mammals. When the principal animal host is not available, human beings can become the victim of mite infestation. Copyright (c) 2007 S. Karger AG, Base