Evolution of Tiling-like Crack Patterns in Maturing Columnar Joints.

Fracture or cracking essentially involves the formation of new interfaces. These patterns are usually studied as two-dimensional mosaics. The new surface that opens up is in the third dimension, along the thickness of the sample. The thickness is usually very small compared to the lateral dimensions of the pattern. A spectacular and distinctive departure from these everyday examples of cracks are columnar joints. Here, molten volcanic lava, by the sea, cools and cracks under appropriate thermal and elastic conditions, causing the crack system to grow downward, creating long, vertical columns with polygonal cross-section. The focus of this paper is the study of the elongated interfaces of these columns: how the cross-section of their outlines gradually undergoes a metamorphosis from a disordered-looking Gilbert tessellation to a well-ordered hexagonal Voronoi pattern. As the columns grow downward to lengths of several meters (in natural systems), their outline continuously changes, the center may shift, causing the column to twist. For the first time, the evolution of these crack mosaics has been simulated and mapped as a trajectory of a 4-vector tuple in a geometry-topology domain. The trajectory of the columnar joint systems is found to depend on the crack seed distribution and crack orientation. An empirical relationship between the system energy and the crack mosaic shape parameter λ has been proposed on the basis of principles of fracture mechanics. The total system energy shows a power-law dependence on λ with the exponent ß âˆ¼ 0.3 and λ ≈ 0.75 at crack maturation. The parameter values are validated by matching the proposed relation with energy estimates existing in the literature. The relation not only matches the visible changes in geometry but also provides a feasible measure of the energy of the system. The geometric energy for the polygonal mosaics in the transverse section has also been estimated as a function of time. The geometric energy moves toward a minimum as the mosaic becomes more Voronoi-like at maturation.

Generating datasets for the project portfolio selection and scheduling problem.

The article presents two variants of the project portfolio selection and scheduling problem (PPSSP). The primary objective of the PPSSP is to maximise the total portfolio value through the selection and scheduling of a subset of projects subject to various operational constraints. This article describes two recently-proposed, generalised models of the PPSSP [1], [2] and proposes a set of synthetically generated problem instances for each. These datasets can be used by researchers to compare the performance of heuristic and meta-heuristic solution strategies. In addition, the Python program used to generate the problem instances is supplied, allowing researchers to generate new problem instances.

Effect of gamma radiation on microbial load, physico-chemical and sensory characteristics of common spices for storage.

The effect of gamma radiation on the decontamination of microbial population, physico-chemical, radiation sensitivity and sensory characteristics of common spices for storage were evaluated. Spices were irradiated with gamma doses of 0 (as control), 2, 4, 6, 8 and 10 kGy, packed in the glass vials and stored at room temperature (22 ± 2°C) in the laboratory. In this research, Bacillus, Salmonella and Listeria species were identified in un-irradiated spice samples. Results also indicated that gamma radiation reduced the total microbial population compared to control and optimum gamma radiation doses (6 kGy for red chili and turmeric; 4 kGy for cumin, coriander, garlic and black pepper; 2 kGy for ginger powder samples) were identified for decontamination of the organisms in the studied spices. It was concluded that no significant differences before and after gamma radiation were observed in physico-chemical, nutritional and sensory properties but significantly changed in microbial load in spices samples.

Effect of dye and temperature on the physico-mechanical properties of jute/PP and jute/LLDPE based composites.

Jute fabrics and unidirectional jute fiber reinforced polypropylene (PP) and linear low density polyethylene (LLDPE) based composites were prepared successfully by compression molding technique. The unidirectional jute fiber was treated with Reactive Orange HB® and Deep Blue LW® dye to investigate physico-mechanical properties. The Reactive Orange HB® treated composites showed relatively better mechanical properties than the Deep Blue LW® treated composites. The jute fiber-based composites showed higher mechanical properties than that of jute-based fabrics. The polypropylene-based composites showed better mechanical properties than that of LLDPE. The variations of mechanical properties were also observed. The highest mechanical properties were at -18 °C and lowest at 50 °C. Water absorbent, SEM and FT-IR analysis of the composite was also carried out.

Elevated Red Blood Cell Distribution Width Combined White Blood Cell in Peripheral Blood Routine Have a Better Sensitivity than CURB-65 Scores in Predicting ICU Admission and Mortality in Adult Community-Acquired Pneumonia Patients.

Background: Scoring systems including CURB-65 and Pneumonia Severity Index (PSI) and novel or traditional biomarkers including procalcitonin (PCT) and c-reactive protein (CRP) are very significant for understanding the severity and prognosis in community-acquired pneumonia (CAP) patients, while prognostic items are useful for CAP prognostication and point-of-care decisions. The aim of this study was to investigate the usefulness of peripheral blood routine items in predicting ICU admission and 30-day mortality in CAP patients.

Methods: A retrospective study was conducted. All adult patients with a primary diagnosis of CAP were included and peripheral blood routine tests were evaluated. Univariate analysis and multivariate logistic regression analysis were used to explore association of risk factors with 30-day mortality among CAP patients. Receiver operating characteristic curves (ROC) were used to evaluate the sensitivity and specificity of peripheral blood routine items and compared with CURB-65 scores in predicting ICU admission and/or 30-day mortality.

Results: One hundred fifty patients were included and compared with non-ICU admission patients. There was a statistically significant difference in age, co-existing illness, RDW, WBC, and CURB-65 scores ranking in ICU admission patients (p < 0.05). In multivariate logistic regression analysis, we found RDW, WBC, and CURB-65 ≥ 3 scores increased the risk of 30-day mortality by 4.01, 1.65, and 3.43 times, respectively. The area under the curve (AUC) of ROC curves of RDW combined with WBC and CURB-65 was 0.786 (95% CI 0.701 to 0.876) and 0.836 (95% CI 0.764 to 0.908), respectively and the sensitivity was 84.0% and 60.0%, respectively, and the specificity 66.7% and 93.7%, respectively.

Conclusions: Elevated RDW and WBC increased mortality in adult CAP patients, RDW combined with WBC had a better sensitivity than CURB-65 scores in predicting ICU admission and/or mortality in CAP patients.

Pathogenesis of Drug Induced Non-Allergic Angioedema: A Review of Unusual Etiologies.

Angioedema is the swelling of mucosal and sub-mucosal tissue. Typically, it manifests as the swelling of the face, lips, and tongue. Angioedema can be severe and life threatening when it involves the respiratory tract. Drug induced allergic angioedema and drug induced non-allergic angioedema differ in their mediator, their clinical presentations, and their management. In drug induced non-allergic angioedema, symptoms are resistant to antihistamine and corticosteroid treatment. The aim of the analysis was to identify which medications are associated with drug-induced non-allergic angioedema and to understand the mechanism of action via which of these medication cause angioedema.

Lignocellulosic-derived modified agricultural waste: development, characterisation and implementation in sequestering pyridine from aqueous solutions.

The development and characterisation of modified agricultural waste (MAW) by H3PO4 activation is addressed in this study for sequestering pyridine from aqueous solutions. The adsorbent is characterised by carbon, hydrogen and nitrogen content of 55.53%, 3.28% and 0.98% respectively. The adsorbent also shows acidic (carboxylic, lactonic, phenolic groups) and basic carbon surface functionalities, functional groups viz. hydroxyl, carboxylic acid and bounded water molecules, BET surface area of 1254.67 m(2) g(-1), heterogeneous surface morphology and graphite like XRD patterns. Adsorption of pyridine is executed to evaluate the adsorptive uptake in batch (q(e)=107.18 mg g(-1)) as well as in column system (q(e)=140.94 mg g(-1)). The adsorption process followed the pseudo-second-order kinetics with the Langmuir isotherm best representing the equilibrium adsorption data. The thermodynamic parameters (ΔH(o)=9.39 kJ mol(-1), ΔG(o)=-5.99 kJ mol(-1), ΔS(o)=50.76 J K(-1) mol(-1)) confirm the endothermic and spontaneous nature of the adsorption process with increase in randomness at solid/solution interface. The adsorption mechanism is governed by electrostatic and π-π dispersive interactions as well as by a two stage diffusion phenomena. Thermally regenerated spent MAW exhibited better adsorption efficiency for five adsorption-desorption cycles than chemically regenerated. The low-cost of MAW (USD 10.714 per kg) and favourable adsorption parameters justifies its use in the adsorptive removal of pyridine.

Nanocellulose-based composites and bioactive agents for food packaging.

Global environmental concern, regarding the use of petroleum-based packaging materials, is encouraging researchers and industries in the search for packaging materials from natural biopolymers. Bioactive packaging is gaining more and more interest not only due to its environment friendly nature but also due to its potential to improve food quality and safety during packaging. Some of the shortcomings of biopolymers, such as weak mechanical and barrier properties can be significantly enhanced by the use of nanomaterials such as nanocellulose (NC). The use of NC can extend the food shelf life and can also improve the food quality as they can serve as carriers of some active substances, such as antioxidants and antimicrobials. The NC fiber-based composites have great potential in the preparation of cheap, lightweight, and very strong nanocomposites for food packaging. This review highlights the potential use and application of NC fiber-based nanocomposites and also the incorporation of bioactive agents in food packaging.

Encapsulation of probiotic bacteria in biopolymeric system.

Encapsulation of probiotic bacteria is generally used to enhance the viability during processing, and also for the target delivery in gastrointestinal tract. Probiotics are used with the fermented dairy products, pharmaceutical products, and health supplements. They play a great role in maintaining human health. The survival of these bacteria in the human gastrointestinal system is questionable. In order to protect the viability of the probiotic bacteria, several types of biopolymers such as alginate, chitosan, gelatin, whey protein isolate, cellulose derivatives are used for encapsulation and several methods of encapsulation such as spray drying, extrusion, emulsion have been reported. This review focuses on the method of encapsulation and the use of different biopolymeric system for encapsulation of probiotics.

Mechanical and barrier properties of nanocrystalline cellulose reinforced chitosan based nanocomposite films.

Nanocrystalline cellulose (NCC) reinforced chitosan-based biodegradable films were prepared by solution casting. The NCC content in the films was varied from 1 to 10% (dry wt. basis). It was found that the tensile strength (TS) of the nanocomposite films with 5% (w/w) NCC content was optimum with an improvement of 26% compared to the control chitosan films. Incorporation of NCC also significantly improved barrier properties. Water vapor permeability (WVP) of the chitosan/NCC films was decreased by 27% for the optimum 5% (w/w) NCC content. Swelling studies revealed a decrease in water uptake of the NCC-reinforced chitosan films. Analyses of thermal properties showed no significant effect of NCC whereas X-ray diffraction studies confirmed the appearance of crystalline peaks in the nanocomposite films. Surface morphology of the films was investigated by scanning electron microscopy and it was found that NCC was dispersed homogenously into chitosan matrix.

Nanocrystalline cellulose (NCC) reinforced alginate based biodegradable nanocomposite film.

Nanocrystalline cellulose (NCC) reinforced alginate-based nanocomposite film was prepared by solution casting. The NCC content in the matrix was varied from 1 to 8% ((w/w) % dry matrix). It was found that the nanocomposite reinforced with 5 wt% NCC content exhibits the highest tensile strength which was increased by 37% compared to the control. Incorporation of NCC also significantly improved water vapor permeability (WVP) of the nanocomposite showing a 31% decrease due to 5 wt% NCC loading. Molecular interactions between alginate and NCC were supported by Fourier Transform Infrared Spectroscopy. The X-ray diffraction studies also confirmed the appearance of crystalline peaks due to the presence of NCC inside the films. Thermal stability of alginate-based nanocomposite films was improved after incorporation of NCC.

Modification and characterization of biodegradable methylcellulose films with trimethylolpropane trimethacrylate (TMPTMA) by γ radiation: effect of nanocrystalline cellulose.

Methylcellulose (MC)-based films were prepared by solution casting from its 1% aqueous suspension containing 0.25% glycerol. Trimethylolpropane trimethacrylate (TMPTMA) monomer (0.1-2% by wt) along with the glycerol was added to the MC suspension. The films were cast and irradiated from a radiation dose varied from 0.1 to 10 kGy. Then the mechanical properties such as tensile strength (TS), tensile modulus (TM), and elongation at break (Eb) and barrier properties of the films were evaluated. The highest TS (47.88 PMa) and TM (1791.50 MPa) of the films were found by using 0.1% monomer at 5 kGy dose. The lowest water vapor permeability (WVP) of the films was found to be 5.57 g·mm/m(2)·day·kPa (at 0.1% monomer and 5 kGy dose), which is 12.14% lower than control MC-based films. Molecular interactions due to incorporation of TMPTMA were supported by FTIR spectroscopy. A band at 1720 cm(-1) was observed due to the addition of TMPTMA in MC-based films, which indicated the typical (C═O) carbonyl stretching. For the further improvement of the mechanical and barrier properties of the film, 0.025-1% nanocrystalline cellulose (NCC) was added to the MC-based suspension containing 1% TMPTMA. Addition of NCC led to a significant improvement in the mechanical and barrier properties. The novelty of this investigation was to graft insoluble monomer using γ radiation with MC-based films and use of biodegradable NCC as the reinforcing agent.

Physico-mechanical properties of wound dressing material and its biomedical application.

A bioadhesive wound dressing material, based on gelatin, was prepared by solution casting, and its properties were evaluated. The tensile strength (TS) and percentage elongation at break (Eb) of the membranes were found to be 12.7 MPa and 40.4%, respectively. The buffer uptake and water uptake of the prepared membranes were found to be 298 and 312%, respectively, after 8 min. A scanning electron micrograph of the membrane revealed its uniform porosity, which is an essential criterion to be an ideal wound dressing. From microbial sensitivity analysis, it was found that the membrane had a significant resistance against infection. The wound-healing characteristics of the membrane were evaluated using a rat (Rattus norvegicus) model. Full-thickness wounds were created on the ventral side of the Rattus norvegicus and were dressed with the membrane; eco-plast was used as a control. The wound healing and bioadhesion were monitored at 3-day intervals by real-time imaging. The results revealed that the prepared membrane was more effective in healing the wound than conventional wound dressing.

Production and properties of nanocellulose-reinforced methylcellulose-based biodegradable films.

Methylcellulose (MC)-based films were prepared by casting from its 1% aqueous solution containing 0.5% vegetable oil, 0.25% glycerol, and 0.025% Tween 80. Puncture strength (PS), puncture deformation (PD), viscoelasticity coefficient, and water vapor permeability (WVP) were found to be 147 N/mm, 3.46 mm, 41%, and 6.34 g.mm/m(2).day.kPa, respectively. Aqueous nanocellulose (NC) solution (0.1-1%) was incorporated into the MC-based formulation, and it was found that PS was improved (117%) and WVP was decreased (26%) significantly. Films containing 0.25% NC were found to be the optimum. Then films were exposed to gamma radiation (0.5-50 kGy), and it was revealed that mechanical properties of the films were slightly decreased after irradiation, whereas barrier properties were further improved with a decrease of WVP to 28.8% at 50 kGy. Molecular interactions due to incorporation of NC were supported by FTIR spectroscopy. Thermal properties of the NC-containing films were improved, confirmed by TGA and DSC. Crystalline peaks appeared due to NC addition, found by XRD. Micrographs of films containing NC were investigated by SEM.

Ferritin and Soluble Transferrin Receptors in Type 2 Diabetic and Non-diabetic Post-menopausal Women in Dhaka, Bangladesh.

This cross-sectional comparative study was aimed at investigating the iron status of a group of post-menopausal women with and without diabetes. Thirty-five post-menopausal women in each group were selected purposively from among patients attending the out-patient department of Bangladesh Institute of Research and Rehabilitation in Diabetes, Endocrine and Metabolic Disorders (BIRDEM), a specialist hospital, and two of its satellite clinics, all in Dhaka. Patients were enrolled based on their existing records. The subjects were matched on age, menstrual status and fasting status at blood draw. Ferritin, serum soluble transferrin receptors (sTfR) and fasting plasma glucose were measured by standard methods. Dietary information was collected by a specific food frequency questionnaire. No significant difference in plasma ferritin [62.02 ng/ml, (range: 4.68-288.89) vs 54.25 ng/ml (range: 4.58-137.17); p=0.28] was observed between the groups. But a higher level of plasma sTfR was found in diabetic women [(21.12 nmol/l (range: 7.91-39.79) vs 17.63 nmol/l (range: 10.30-110.00); p<0.01]. TFR-F index showed no difference between diabetic and control (p=0.25). Significantly a lower hemoglobin level [10.58±0.67 g/dl vs11.76±1.5 g/dl; p<0.01] was detected in diabetic women. Plasma sTfR (log) did not show any significant association with the dietary parameters and iron indices. No significant association between fasting glucose, ferritin and sTfR was seen except for haemoglobin (r=0.39, p=0.05). Total iron intake recorded was more than the requirement, and was significantly higher in control group [38.11mg/day (range: 19.83-105.63) vs 56.65 mg/day (range: 29.75-109.54); p<0.01)]. More than 97 % of total iron was of plant origin. No differences in heme iron [0.85 mg/day (range: 0.09-4.07) vs. 0.96 mg/day (range: 0.04-4.34), p= 0.17] and vitamin C intake was observed between the groups. Iron indices of non-diabetic women were within the normal range. A higher level of sTfR and a lower level of hemoglobin in diabetic cases is suggestive of iron deficiency anaemia rather than iron overload.

Ferritin and Soluble Transferrin Receptors in Type 2 Diabetic and Non-diabetic Post-menopausal Women in Dhaka, Bangladesh

This cross-sectional comparative study was aimed at investigating the iron status of a group of post-menopausal women with and without diabetes. Thirty-five post-menopausal women in each group were selected purposively from among patients attending the out-patient department of Bangladesh Institute of Research and Rehabilitation in Diabetes, Endocrine and Metabolic Disorders (BIRDEM), a specialist hospital, and two of its satellite clinics, all in Dhaka. Patients were enrolled based on their existing records. The subjects were matched on age, menstrual status and fasting status at blood draw. Ferritin, serum soluble transferrin receptors (sTfR) and fasting plasma glucose were measured by standard methods. Dietary information was collected by a specific food frequency questionnaire. No significant difference in plasma ferritin [62.02 ng/ml, (range:4.68-288.89) vs 54.25 ng/ml (range: 4.58-137.17); p=0.28] was observed between the groups. But a higher level of plasma sTfR was found in diabetic women [(21.12 nmol/l (range: 7.91-39.79) vs 17.63 nmol/l (range: 10.30-110.00); p<0.01]. TFR-F index showed no difference between diabetic and control (p=0.25). Significantly a lower hemoglobin level [10.58±0.67 g/dl vs11.76±1.5 g/dl; p<0.01] was detected in diabetic women. Plasma sTfR (log) did not show any significant association with the dietary parameters and iron indices. No significant association between fasting glucose, ferritin and sTfR was seen except for haemoglobin (r=0.39, p=0.05). Total iron intake recorded was more than the requirement, and was significantly higher in control group [38.11mg/day (range: 19.83-105.63) vs 56.65 mg/day (range: 29.75-109.54); p<0.01)]. More than 97 % of total iron was of plant origin. No differences in heme iron [0.85 mg/day (range:0.09-4.07) vs. 0.96 mg/day (range: 0.04-4.34), p= 0.17] and vitamin C intake was observed between the groups. Iron indices of non-diabetic women were within the normal range. A higher level of sTfR and a lower level of hemoglobin in diabetic cases is suggestive of iron deficiency anaemia rather than iron overload.

[Usefulness of self ligation mediated polymerase chain reaction: a rapid method for fingerprinting in molecular epidemiology of tuberculosis].

Restriction fragment length polymorphism (RFLP) analysis based on the insertion sequence IS 6110 has been used as one of the powerful tools for epidemiological study of tuberculosis. However this technique requires more than 1 micro-gram of DNA and two days for completion. To overcome these inconvenience, we have modified a PCR-based method, self ligation mediated PCR (SL-PCR) on the molecular epidemiological study. This method uses a pair of primers whose orientations are from inside to outside of IS 6110. The DNA fragments flanking IS 6110 are amplified by the PCR by using the Sau 3A I digested and ligated chromosomal DNA of Mycobacterium tuberculosis strains. By using this method, M. tuberculosis strains can be differentiated within 8 hours.

Molecular cloning and characterization of the gene coding for azoreductase from Bacillus sp. OY1-2 isolated from soil.

Azo dyes are regarded as pollutants because they are not readily reduced under aerobic conditions. Bacillus sp. OY1-2 transforms azo dyes into colorless compounds, and this reduction is mediated by a reductase activity for the azo group in the presence of NADPH. A 1.2-kbp EcoRI fragment containing the gene that encodes azoreductase was cloned by screening the genomic library of Bacillus sp. OY1-2 with digoxigenin-labeled probe designed from the N-terminal amino acid sequence of the purified enzyme. An open reading frame encoding the azoreductase, consisting of 178 amino acids, was predicted from the nucleotide sequence. In addition, because only a Bacillus subtillis hypothetical protein was discovered in the public databases (with an amino acid identity of 52.8%), the gene encoding the azoreductase cloned in this study was predicted to be a member of a novel family of reductases. Southern blot analysis revealed that the azoreductase gene exists as a single copy gene on a chromosome. Escherichia coli-expressing recombinant azoreductase gave a ten times greater reducing activity toward azo dyes than the original Bacillus sp. OY1-2. In addition, the expressed azoreductase purified from the recombinant E. coli lysate by Red-Sepharose affinity chromatography showed a similar activity and specificity as the native enzyme. This is the first report describing the sequencing and characterization of a gene encoding the azo dye-reducing enzyme, azoreductase, from aerobic bacteria and its expression in E. coli.

Public health services in Bangladesh with special reference to systems and trends of vital statistics.

Health is one of the basic requirements for improvement in the quality of life. Since Bangladesh became independent, a policy for providing essential minimum health care to all has been actively pursued.An overview of Public Health Services in Bangladesh is presented in terms of: (1) a profile of the country, (2) an overview of public health, (3) medical care, and (4) environmental health. Under each of these headings observations are included on recent trends based upon relevant data and information.Finally the authors describe the importance of (1) promotion of health care and planning at the national, divisional, local, and community levels, (2) promotion of medical services at all levels, and (3) effective decentralization of health services to enhance the services of health facilities.