bluuebunny/crossref_metadata_2025 huggingface dataset:
Cadaveric Study of the Anatomical Variations of the Accessory Pancreatic Duct
Authors: Shahriah Sunjida , Nurunnabi Abu Sadat Mohammad , Johora Fatema , Siddiqua Dilruba , Ara Shamim
Published: March 2015

Background: The accessory pancreatic duct enters the duodenum at the minor duodenal papilla, developmentally draining the dorsal pancreatic bud; however, it is smaller and less constant than the main pancreatic duct and undergoes varying degrees of atrophy at the duodenal end. Objective: The objective of this study was to see the variations in course, opening and communication pattern of the accessory pancreatic duct in different age-groups in a Bangladeshi population. Methods: This crosssectional, descriptive study was done was done in the Department of Anatomy, Dhaka Medical College, Dhaka, from August 2005 to December 2006, based on collection and dissection of 75 postmortem male human pancreas. The collected samples were divided into seven age groups: 10-19 years, 20-29 years,30-39 years, 40-49 years, 50-59 years),60-69 years and(e70 years. However, 65 samples were taken for final observation. Results: The accessory pancreatic duct was found in 27.69% specimens. Straight course was found in 50% specimen, while spindle course in 27.78% and cudgel course in 22.22% specimens were observed. In only 4 (6.15%) specimens, the accessory pancreatic duct communicates with the common bile duct, while in 11 (16.93%) specimens, the accessory pancreatic duct communicates with the main pancreatic duct. 12 (66.67%) accessory pancreatic ducts opened into the minor duodenal papilla, while 5 (27.78%) into the major duodenal papilla and 1 (5.55%) into the 3rd duodenal papilla. Conclusion: Several variations were observed in accessory pancreatic duct pattern in terms of their course, opening and communications. However, no significant differences were evident in any parameter among the age groups. Here, females were excluded due to less availability of the female cadaveric pancreas during study period. DOI: http://dx.doi.org/10.3329/jbsp.v9i2.22802 Bangladesh Soc Physiol. 2014, December; 9(2): 83-88
Non- Pharmacological Measures for Control of Hypertension in Geriatric Population
Authors: Sahoo Debalina , Gosai Harshida , Sahoo Ujjwal , Harsoda JM
Published: March 2015

Background: Increased prevalence of hypertension in all over the world is well recognized. Hypertension affects almost all body organs and systems. It can be managed by using nonpharmacological measures as well. Objective: To assess knowledge of non-pharmacological measures to control of hypertension and its application in geriatric hypertensive population. Methods: The study was conducted in the Department of Physiology, Sumandeep Vidyapeeth University, Vadodara. Total 108 hypertensive patients had been included for this study. Subjects were administered pre tested ten questionnaires. They responded the questionnaires at the same time, without any discussion. Results: Knowledge about normal level of blood pressure was lacking in 70% of study population. Conclusion: Knowledge about weight reduction, regular exercise, fruits and vegetables intake was poor. About half of the study population said that blood pressure can be controlled by using of drugs only. So, they were not aware of non-pharmacological measures. DOI: http://dx.doi.org/10.3329/jbsp.v9i2.22804 Bangladesh Soc Physiol. 2014, December; 9(2): 94-97
Pre Clinical- Basic Sciences Teaching Curriculum of a Medical School in a Developing Country -Are We Doing it Right?
Authors: Atukorala Kushani Rasangika , Atapattu Piyusha
Published: March 2015

Background: Preclinical teaching of basic sciences provides the basis for the development of clinical reasoning skills and the ability to make management decisions. However, many senior undergraduates, pre-interns and doctors indicate that basic sciences knowledge is poorly recalled and has little relevance to their clinical practice. Objectives: To explore the perceptions of medical students in their clinical years, and pre-interns about the basic sciences courses taught to them in the preclinical years, and to assess how each group rates the applicability of these courses to current clinical training. Methods: A descriptive cross-sectional study was conducted among 118 pre-interns and 146 undergraduate medical students using a self-administered questionnaire, regarding their perceptions on preclinical basic sciences teaching. For statistical analysis chi square test was applied. Results: More than 75% both pre-interns and undergraduates agreed that preclinical teaching was useful and relevant for future clinical work. 50-75% frequently revisited preclinical subjects despite unapparent clinical significance. 55% couldnt remember most of preclinical content. Physiology was the most retained (76%) and most clinically relevant subject (80%). Majority of (>60%) both the groups suggested more teaching time and >75% suggested concurrent clinical exposure for preclinical teaching. Undergraduates and preinterns differed in that 56% of undergraduates and 37% of pre-interns had studied pre clinical subjects just to pass examinations (p<0.01) Conclusions: Majority of undergraduates and pre-interns felt that preclinical teaching is interesting and relevant for future clinical practice, though recall and clinical significance were suboptimal. Revising teaching methods with interdisciplinary integration, early clinical exposure showing relevance of basic sciences and allocating more teaching time utilizing clinicians should be considered. DOI: http://dx.doi.org/10.3329/jbsp.v9i2.22806 Bangladesh Soc Physiol. 2014, December; 9(2): 98-104
Goitrogenic and Antithyroid Potential of Green Tea of Indian Origin
Authors: Chandra Amar K , De Neela
Published: March 2015

Polyphenolic flavonoids, specially catechins are major constituents of tea. Antithyroidal and goitrogenic effect of flavonoids have been reported however such effects of green tea on thyroid physiology has not been explored earlier. Green tea is derived from the tea leaves of Camellia sinensis and widely consumed globally. The green tea extracts(GTE) at different concentrations (1.25g% a 5 cups of tea/ day; 2.5g% a 10 cups of tea/ day and 5.0g% a 20 cups of tea/ day) were orally fed to male rats for 30 days. Similarly, pure catechin was administered orally to male albino rats for 30 days at doses of 25, 50 and 100 mg/kg body weight that are equivalent to above doses of green tea extract in terms of its total catechin content and the morphological and functional changes of the thyroid have been investigated. The overall results reveal that oral administration of green tea extract at 2.5g% and 5.0g% concentrations for 30 days changed the morphology and histology resembling hypertrophy of thyroid follicles with differential colloid sizes as found in hypothyroid due to environment influences associated with significant inhibited activities of thyroid peroxidase(TPO) and 5 monodeiodinase (5 DI1) with elevated Na+,K+ ATPase and concomitant decrease in serum thyroxine (T4), triiodothyronine (T3) and increase in serum thyrotropin (TSH) levels developing a state of absolute biochemical hypothyroidism. All these suggest that catechin present in green tea has the antithyroidal as well as goitrogenic potential and its regular consumption at relatively high doses pose a threat to the functioning of thyroid. DOI: http://dx.doi.org/10.3329/jbsp.v9i2.22807 Bangladesh Soc Physiol. 2014, December; 9(2): 105-116
Business Contingency, Strategy Formation, and Firm Performance: An Empirical Study of Chinese Apparel SMEs
Authors: Chi Ting
Published: March 2015

This study empirically investigated how small and medium-sized Chinese apparel enterprises (SME) formed their strategy as a response to the characteristics of business environment in order to achieve competitive business performance. An environment-strategy-performance model was proposed and tested. Using primary data gathered by a questionnaire survey of the Chinese apparel industry, factor analysis and structural equation modeling (SEM) were conducted for measurement and structural model analysis and hypothesis testing. Results show the proposed model met parsimonious statistical criteria. The differences in strategy responses to environment between high- and low-performing firms were striking. Confronting an increasingly turbulent business environment, high performers emphasized differentiation strategy through higher quality, better delivery performance, and greater flexibility than cost reduction. In contrast, low performers prioritized low cost while quality and flexibility were given certain weights. The lack of clear focus on strategies could result in a relatively lower performance. While the process of government-led industrial upgrading continues, forward-looking firms have proactively shifted their strategic focus from solely or mainly cost reduction to a variety of differentiating factors which bring in added value and are less imitable by competitors.
Host Defense Peptides from Asian Frogs as Potential Clinical Therapies
Authors: Kumar Vineeth , Holthausen David , Jacob Joshy , George Sanil
Published: March 2015

Host defense peptides (HDPs) are currently major focal points of medical research as infectious microbes are gaining resistance to existing drugs. They are effective against multi-drug resistant pathogens due to their unique primary target, biological membranes, and their peculiar mode of action. Even though HDPs from 60 Asian frog species belonging to 15 genera have been characterized, research into these peptides is at a very early stage. The purpose of this review is to showcase the status of peptide research in Asia. Here we provide a summary of HDPs from Asian frogs.
Comparison of Fresh and Commercial Pomegranate Juices from Mollar de Elche Cultivar Grown under Conventional or Organic Farming Practices
Authors: Nuncio-Jáuregui Nallely , Cano-Lamadrid Marina , Hernández Francisca , Carbonell-Barrachina Ángel , Calín-Sánchez Ángel
Published: March 2015

Pomegranate juice has gained a high reputation for its health properties and consequently is now a highly demanded product. However, there is an interest in knowing if there are differences between conventional and organic agricultural practices. For that reason, total phenolic content, antioxidant capacity, punicalagin isomers and sensory analysis of pomegranate juices from Mollar de Elche cultivar were studied. A comparison between fresh and commercial pomegranate juice obtained by conventional and organic agricultural practices was conducted. The total phenolic content values ranged from 2285 to 2457 mg GAE L−1; however, there was no significant difference among conventional and organic juices. The antioxidant capacity evaluated by DPPH and ABTS methods showed significant differences (p < 0.05) among conventional and organic juices. The antioxidant capacity values ranged from 17.7 to 35.9 mmol Trolox L−1 for DPPH and from 5.09 to 27.9 mmol Trolox L-1 for ABTS. Significant differences (p < 0.05) were observed among conventional and organic juices in punicalagin isomer, with the highest value found in conventional fresh pomegranate juice (0.48 g L−1). Descriptive sensory analysis showed that fresh pomegranate, fresh rind, earthy, vegetal, bitter, and astringent notes were higher in conventional fresh pomegranate juice. Cooked and mushroom notes predominated in conventional commercial pomegranate juice; while the organic juice was characterized by fresh pomegranate, fresh rind, earthy and sweet notes.
Generalized Remote Preparation of Arbitrary m-qubit Entangled States via Genuine Entanglements
Authors: Wang Dong , Hoehn Ross , Ye Liu , Kais Sabre
Published: March 2015

Herein, we present a feasible, general protocol for quantum communication within a network via generalized remote preparation of an arbitrary m-qubit entangled state designed with genuine tripartite Greenberger–Horne–Zeilinger-type entangled resources. During the implementations, we construct novel collective unitary operations; these operations are tasked with performing the necessary phase transfers during remote state preparations. We have distilled our implementation methods into a five-step procedure, which can be used to faithfully recover the desired state during transfer. Compared to previous existing schemes, our methodology features a greatly increased success probability. After the consumption of auxiliary qubits and the performance of collective unitary operations, the probability of successful state transfer is increased four-fold and eight-fold for arbitrary two- and three-qubit entanglements when compared to other methods within the literature, respectively. We conclude this paper with a discussion of the presented scheme for state preparation, including: success probabilities, reducibility and generalizability.
Multidimensional Scaling Visualization Using Parametric Similarity Indices
Authors: Tenreiro Machado J. , Lopes António , Galhano Alexandra
Published: March 2015

In this paper, we apply multidimensional scaling (MDS) and parametric similarity indices (PSI) in the analysis of complex systems (CS). Each CS is viewed as a dynamical system, exhibiting an output time-series to be interpreted as a manifestation of its behavior. We start by adopting a sliding window to sample the original data into several consecutive time periods. Second, we define a given PSI for tracking pieces of data. We then compare the windows for different values of the parameter, and we generate the corresponding MDS maps of ‘points’. Third, we use Procrustes analysis to linearly transform the MDS charts for maximum superposition and to build a globalMDS map of “shapes”. This final plot captures the time evolution of the phenomena and is sensitive to the PSI adopted. The generalized correlation, theMinkowski distance and four entropy-based indices are tested. The proposed approach is applied to the Dow Jones Industrial Average stock market index and the Europe Brent Spot Price FOB time-series.
Preclinical Diagnosis of Magnetic Resonance (MR) Brain Images via Discrete Wavelet Packet Transform with Tsallis Entropy and Generalized Eigenvalue Proximal Support Vector Machine (GEPSVM)
Authors: Zhang Yudong , Dong Zhengchao , Wang Shuihua , Ji Genlin , Yang Jiquan
Published: March 2015

Background: Developing an accurate computer-aided diagnosis (CAD) system of MR brain images is essential for medical interpretation and analysis. In this study, we propose a novel automatic CAD system to distinguish abnormal brains from normal brains in MRI scanning. Methods: The proposed method simplifies the task to a binary classification problem. We used discrete wavelet packet transform (DWPT) to extract wavelet packet coefficients from MR brain images. Next, Shannon entropy (SE) and Tsallis entropy (TE) were harnessed to obtain entropy features from DWPT coefficients. Finally, generalized eigenvalue proximate support vector machine (GEPSVM), and GEPSVM with radial basis function (RBF) kernel, were employed as classifier. We tested the four proposed diagnosis methods (DWPT + SE + GEPSVM, DWPT + TE + GEPSVM, DWPT + SE + GEPSVM + RBF, and DWPT + TE + GEPSVM + RBF) on three benchmark datasets of Dataset-66, Dataset-160, and Dataset-255. Results: The 10 repetition of K-fold stratified cross validation results showed the proposed DWPT + TE + GEPSVM + RBF method excelled not only other three proposed classifiers but also existing state-of-the-art methods in terms of classification accuracy. In addition, the DWPT + TE + GEPSVM + RBF method achieved accuracy of 100%, 100%, and 99.53% on Dataset-66, Dataset-160, and Dataset-255, respectively. For Dataset-255, the offline learning cost 8.4430s and online prediction cost merely 0.1059s. Conclusions: We have proved the effectiveness of the proposed method, which achieved nearly 100% accuracy over three benchmark datasets.
Optimizing Capacities of Distributed Generation and Energy Storage in a Small Autonomous Power System Considering Uncertainty in Renewables
Authors: Hong Ying-Yi , Lai Yuan-Ming , Chang Yung-Ruei , Lee Yih-Der , Liu Pang-Wei
Published: March 2015

This paper explores real power generation planning, considering distributed generation resources and energy storage in a small standalone power system. On account of the Kyoto Protocol and Copenhagen Accord, wind and photovoltaic (PV) powers are considered as clean and renewable energies. In this study, a genetic algorithm (GA) was used to determine the optimal capacities of wind-turbine-generators, PV, diesel generators and energy storage in a small standalone power system. The investment costs (installation, unit and maintenance costs) of the distributed generation resources and energy storage and the cost of fuel for the diesel generators were minimized while the reliability requirement and CO2 emission limit were fulfilled. The renewable sources and loads were modeled by random variables because of their uncertainties. The equality and inequality constraints in the genetic algorithms were treated by cumulant effects and cumulative probability of random variables, respectively. The IEEE reliability data for an 8760 h load profile with a 150 kW peak load were used to demonstrate the applicability of the proposed method.
Microsatellite Instability Use in Mismatch Repair Gene Sequence Variant Classification
Authors: Thompson Bryony , Spurdle Amanda
Published: March 2015

Inherited mutations in the DNA mismatch repair genes (MMR) can cause MMR deficiency and increased susceptibility to colorectal and endometrial cancer. Microsatellite instability (MSI) is the defining molecular signature of MMR deficiency. The clinical classification of identified MMR gene sequence variants has a direct impact on the management of patients and their families. For a significant proportion of cases sequence variants of uncertain clinical significance (also known as unclassified variants) are identified, constituting a challenge for genetic counselling and clinical management of families. The effect on protein function of these variants is difficult to interpret. The presence or absence of MSI in tumours can aid in determining the pathogenicity of associated unclassified MMR gene variants. However, there are some considerations that need to be taken into account when using MSI for variant interpretation. The use of MSI and other tumour characteristics in MMR gene sequence variant classification will be explored in this review.
Blunt Snout Bream (Megalobrama amblycephala) MyD88 and TRAF6: Characterisation, Comparative Homology Modelling and Expression
Authors: Tran Ngoc , Liu Han , Jakovlić Ivan , Wang Wei-Min
Published: March 2015

MyD88 and TRAF6 play an essential role in the innate immune response in most animals. This study reports the full-length MaMyD88 and MaTRAF6 genes identified from the blunt snout bream (Megalobrama amblycephala) transcriptome profile. MaMyD88 is 2501 base pairs (bp) long, encoding a putative protein of 284 amino acids (aa), including the N-terminal DEATH domain of 78 aa and the C-terminal TIR domain of 138 aa. MaTRAF6 is 2252 bp long, encoding a putative protein of 542 aa, including the N-terminal low-complexity region, RING domain (40 aa), a coiled-coil region (64 aa) and C-terminal MATH domain (147 aa). Coding regions of MaMyD88 and MaTRAF6 genomic sequences consisted of five and six exons, respectively. Physicochemical and functional characteristics of the proteins were analysed. Alpha helices were dominant in the secondary structure of the proteins. Homology models of the MaMyD88 and MaTRAF6 domains were constructed applying the comparative modelling method. RT-qPCR was used to analyse the expression of MaMyD88 and MaTRAF6 mRNA transcripts in response to Aeromonas hydrophila challenge. Both genes were highly upregulated in the liver, spleen and kidney during the first 24 h after the challenge. While MyD88 and TRAF6 have been reported in various aquatic species, this is the first report and characterisation of these genes in blunt snout bream. This research also provides evidence of the important roles of these two genes in the blunt snout bream innate immune system.
Identification and Functional Analysis of MicroRNAs and Their Targets in Platanus acerifolia under Lead (Pb) Stress
Authors: Wang Yuanlong , Zhao Zhenli , Deng Minjie , Liu Rongning , Niu Suyan , Fan Guoqiang
Published: March 2015

MicroRNAs (miRNAs) play important regulatory roles in development and stress responses in plants. Lead (Pb) is a non-essential element that is highly toxic to living organisms. Platanus acerifolia is grown as a street tree in cities throughout temperate regions for its importance in improving the urban ecological environment. MiRNAs that respond to abiotic stresses have been identified in plants; however, until now, the influence of Pb stress on P. acerifolia miRNAs has not been reported. To identify miRNAs and predict their target genes under Pb stress, two small RNA and two degradome libraries were constructed from Pb-treated and Pb-free leaves of P. acerifolia seedlings. After sequencing, 55 known miRNAs and 129 novel miRNAs were obtained, and 104 target genes for the miRNAs were identified by degradome sequencing. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were performed to predict the functions of the targets. The expressions of eight differentially expressed miRNAs were validated by quantitative real-time polymerase chain reaction (qRT-PCR). This is the first report about P. acerifolia miRNAs and their target genes under Pb stress. This study has provided data for further research into molecular mechanisms involved in resistance of P. acerifolia to Pb stress.
Unfolding the Unfolded Protein Response: Unique Insights into Brain Ischemia
Authors: Sanderson Thomas , Gallaway Molly , Kumar Rita
Published: March 2015

The endoplasmic reticulum (ER) is responsible for processing of proteins that are destined to be secreted, enclosed in a vesicle, or incorporated in the plasma membrane. Nascent peptides that enter the ER undergo a series of highly regulated processing steps to reach maturation as they transit the ER. Alterations in the intracellular environment that induce ER stress are thought to interrupt these processing steps, and result in unfolding of proteins in the ER. Accumulation of unfolded proteins concurrently activates three transmembrane stress sensors, IRE1, ATF6 and PERK, and is referred to as the Unfolded Protein Response (UPR). Our understanding of the mechanisms of UPR induction has been assembled primarily from experiments inducing ER stress with chemical and genetic manipulations. However, physiological stress often induces activation of ER stress sensors in a distinct manner from the canonical UPR. The unique activation profiles in vivo have prompted us to examine the mechanism of UPR activation in neurons following cerebral ischemia.
Organocatalytic Upgrading of Furfural and 5-Hydroxymethyl Furfural to C10 and C12 Furoins with Quantitative Yield and Atom-Efficiency
Authors: Zang Hongjun , Chen Eugene
Published: March 2015

There is increasing interest in the upgrading of C5 furfural (FF) and C6 5-hydroxymethyl furfural (HMF) into C10 and C12 furoins as higher energy-density intermediates for renewable chemicals, materials, and biofuels. This work utilizes the organocatalytic approach, using the in situ generated N,S-heterocyclic carbene catalyst derived from thiazolium ionic liquids (ILs), to achieve highly efficient self-coupling reactions of FF and HMF. Specifically, variations of the thiazolium IL structure have led to the most active and efficient catalyst system of the current series, which is derived from a new thiazolium IL carrying the electron-donating acetate group at the 5-ring position. For FF coupling by this IL (0.1 mol %, 60 °C, 1 h), when combined with Et3N, furoin was obtained in >99% yield. A 97% yield of the C12 furoin was also achieved from the HMF coupling by this catalyst system (10 mol % loading, 120 °C, 3 h). On the other hand, the thiazolium IL bearing the electron-withdrawing group at the 5-ring position is the least active and efficient catalyst. The mechanistic aspects of the coupling reaction by the thiazolium catalyst system have also been examined and a mechanism has been proposed.
Interaction of tRNA with Eukaryotic Ribosome
Authors: Graifer Dmitri , Karpova Galina
Published: March 2015

This paper is a review of currently available data concerning interactions of tRNAs with the eukaryotic ribosome at various stages of translation. These data include the results obtained by means of cryo-electron microscopy and X-ray crystallography applied to various model ribosomal complexes, site-directed cross-linking with the use of tRNA derivatives bearing chemically or photochemically reactive groups in the CCA-terminal fragment and chemical probing of 28S rRNA in the region of the peptidyl transferase center. Similarities and differences in the interactions of tRNAs with prokaryotic and eukaryotic ribosomes are discussed with concomitant consideration of the extent of resemblance between molecular mechanisms of translation in eukaryotes and bacteria.
Using iPS Cells toward the Understanding of Parkinson’s Disease
Authors: Torrent Roger , De Angelis Rigotti Francesca , Dell'Era Patrizia , Memo Maurizio , Raya Angel , Consiglio Antonella
Published: March 2015

Cellular reprogramming of somatic cells to human pluripotent stem cells (iPSC) represents an efficient tool for in vitro modeling of human brain diseases and provides an innovative opportunity in the identification of new therapeutic drugs. Patient-specific iPSC can be differentiated into disease-relevant cell types, including neurons, carrying the genetic background of the donor and enabling de novo generation of human models of genetically complex disorders. Parkinson’s disease (PD) is the second most common age-related progressive neurodegenerative disease, which is mainly characterized by nigrostriatal dopaminergic (DA) neuron degeneration and synaptic dysfunction. Recently, the generation of disease-specific iPSC from patients suffering from PD has unveiled a recapitulation of disease-related cell phenotypes, such as abnormal α-synuclein accumulation and alterations in autophagy machinery. The use of patient-specific iPSC has a remarkable potential to uncover novel insights of the disease pathogenesis, which in turn will open new avenues for clinical intervention. This review explores the current Parkinson’s disease iPSC-based models highlighting their role in the discovery of new drugs, as well as discussing the most challenging limitations iPSC-models face today.
Evolutionary Aspects and Regulation of Tetrapyrrole Biosynthesis in Cyanobacteria under Aerobic and Anaerobic Environments
Authors: Fujita Yuichi , Tsujimoto Ryoma , Aoki Rina
Published: March 2015

Chlorophyll a (Chl) is a light-absorbing tetrapyrrole pigment that is essential for photosynthesis. The molecule is produced from glutamate via a complex biosynthetic pathway comprised of at least 15 enzymatic steps. The first half of the Chl pathway is shared with heme biosynthesis, and the latter half, called the Mg-branch, is specific to Mg-containing Chl a. Bilin pigments, such as phycocyanobilin, are additionally produced from heme, so these light-harvesting pigments also share many common biosynthetic steps with Chl biosynthesis. Some of these common steps in the biosynthetic pathways of heme, Chl and bilins require molecular oxygen for catalysis, such as oxygen-dependent coproporphyrinogen III oxidase. Cyanobacteria thrive in diverse environments in terms of oxygen levels. To cope with Chl deficiency caused by low-oxygen conditions, cyanobacteria have developed elaborate mechanisms to maintain Chl production, even under microoxic environments. The use of enzymes specialized for low-oxygen conditions, such as oxygen-independent coproporphyrinogen III oxidase, constitutes part of a mechanism adapted to low-oxygen conditions. Another mechanism adaptive to hypoxic conditions is mediated by the transcriptional regulator ChlR that senses low oxygen and subsequently activates the transcription of genes encoding enzymes that work under low-oxygen tension. In diazotrophic cyanobacteria, this multilayered regulation also contributes in Chl biosynthesis by supporting energy production for nitrogen fixation that also requires low-oxygen conditions. We will also discuss the evolutionary implications of cyanobacterial tetrapyrrole biosynthesis and regulation, because low oxygen-type enzymes also appear to be evolutionarily older than oxygen-dependent enzymes.
Modeling the Role of pH on Baltic Sea Cyanobacteria
Authors: Hinners Jana , Hofmeister Richard , Hense Inga
Published: March 2015

We simulate pH-dependent growth of cyanobacteria with an ecosystem model for the central Baltic Sea. Four model components—a life cycle model of cyanobacteria, a biogeochemical model, a carbonate chemistry model and a water column model—are coupled via the framework for aquatic biogeochemical models. The coupled model is forced by the output of a regional climate model, based on the A1B emission scenario. With this coupled model, we perform simulations for the period 1968–2098. Our simulation experiments suggest that in the future, cyanobacteria growth is hardly affected by the projected pH decrease. However, in the simulation phase prior to 1980, cyanobacteria growth and N2-fixation are limited by the relatively high pH. The observed absence of cyanobacteria before the 1960s may thus be explained not only by lower eutrophication levels, but also by a higher alkalinity.
Tribo-electrification and Powder Adhesion Studies in the Development of Polymeric Hydrophilic Drug Matrices
Authors: Ghori Muhammad , Šupuk Enes , Conway Barbara
Published: March 2015

The generation of tribo-electric charge during pharmaceutical powder processing can cause a range of complications, including segregation of components leading to content uniformity and particle surface adhesion. This phenomenon becomes problematical when excipients are introduced to a powder mixture alongside the highly charging active pharmaceutical ingredient(s) (APIs). The aim of this study was to investigate the tribo-electric charging and adhesion properties of a model drug, theophylline. Moreover, binary powder mixtures of theophylline with methylcellulose (MC) and hydroxypropyl methylcellulose (HPMC), having different polymer to drug ratios, were formed in order to study the impact of polymer concentration, particle size, substitution ratio and molecular size on the tribo-electric charging and surface adhesion properties of the drug. Furthermore, the relationship between tribo-electric charging and surface adhesion was also studied. The diversity in physicochemical properties of MC/HPMC has shown a significant impact on the tribo-electric charging and adhesion behaviour of theophylline. It was found that the magnitude of electrostatic charge and the level of surface adhesion of the API were significantly reduced with an increase in MC and HPMC concentration, substitution ratios and molecular size. In addition, the tribo-electric charge showed a linear relationship with particle surface adhesion, but the involvement of other forces cannot be neglected.
High-Temperature Oxidation of Fe3Al Intermetallic Alloy Prepared by Additive Manufacturing LENS
Authors: Łyszkowski Radosław
Published: March 2015

The isothermal oxidation of Fe-28Al-5Cr (at%) intermetallic alloy microalloyed with Zr and B (<0.08 at%) in air atmosphere, in the temperature range of 1000 to 1200 °C, was studied. The investigation was carried out on the thin-walled (<1 mm) elements prepared by Laser Engineered Net Shaping (LENS) from alloy powder of a given composition. Characterization of the specimens, after the oxidation, was conducted using X-ray diffraction (XRD) and scanning electron microscopy (SEM, with back-scatter detector (BSE) and energy-dispersive X-ray spectroscopy (EDS) attachments). The investigation has shown, that the oxidized samples were covered with a thin, homogeneous α-Al2O3 oxide layers. The intensity of their growth indicates that the material lost its resistance to oxidation at 1200 °C. Structural analysis of the thin-walled components’ has not shown intensification of the oxidation process at the joints of additive layers.
Seco-Taondiol, an Unusual Meroterpenoid from the Chilean Seaweed Stypopodium flabelliforme and Its Gastroprotective Effect in Mouse Model
Authors: Areche Carlos , Benites Julio , Cornejo Alberto , Ruiz Lina , García-Beltrán Olimpo , Simirgiotis Mario , Sepúlveda Beatriz
Published: March 2015

Ten known meroterpenoids and the new meroterpenoid 7 were isolated from the Chilean seaweed Stypopodium flabelliforme as their acetylated derivatives. Furthermore, the known metabolite taondiol has been isolated for the first time from this species. The molecular structure of the new metabolite was determined by spectroscopic methods based on 1D- and 2D-NMR. Isolation of 7 represents a key step toward a better understanding of the biogenesis of this class of meroterpenoids. Among the meroditerpenoids isolated, stypodiol, isoepitaondiol, epitaondiol and sargaol exhibited gastroprotective activity on the HCl/Ethanol-induced gastric lesions model in mice. Regarding the mode of gastroprotective action, the activity of epitaondiol was reversed significantly when animals were pretreated with indomethacin, N-ethylmaleimide and N-nitro-l-arginine methyl ester (L-NAME) suggesting that prostaglandins, sulfhydryl groups and nitric oxide are involved in their mode of gastroprotective action. In the case of sargaol the gastroprotective activity was attenuated with indomethacin and N-ethylmaleimide, which suggests that prostaglandins and sulfhydryl groups are also involved in the mode of action using this model.
Co-Processed Chitin-Mannitol as a New Excipient for Oro-Dispersible Tablets
Authors: Daraghmeh Nidal , Chowdhry Babur , Leharne Stephen , Al Omari Mahmoud , Badwan Adnan
Published: March 2015

This study describes the preparation, characterization and performance of a novel excipient for use in oro-dispersible tablets (ODT). The excipient (Cop–CM) consists of chitin and mannitol. The excipient with optimal physicochemical properties was obtained at a chitin: mannitol ratio of 2:8 (w/w) and produced by roll compaction (RC). Differential scanning calorimetry (DSC), Fourier transform-Infrared (FT-IR), X-ray powder diffraction (XRPD) and scanning electron microscope (SEM) techniques were used to characterize Cop–CM, in addition to characterization of its powder and ODT dosage form. The effect of particle size distribution of Cop–CM was investigated and found to have no significant influence on the overall tablet physical properties. The compressibility parameter (a) for Cop–CM was calculated from a Kawakita plot and found to be higher (0.661) than that of mannitol (0.576) due to the presence of the highly compressible chitin (0.818). Montelukast sodium and domperidone ODTs produced, using Cop–CM, displayed excellent physicochemical properties. The exceptional binding, fast wetting and superdisintegration properties of Cop–CM, in comparison with commercially available co-processed ODT excipients, results in a unique multifunctional base which can successfully be used in the formulation of oro-dispersible and fast immediate release tablets.
Low Molecular Weight Chitosan–Insulin Polyelectrolyte Complex: Characterization and Stability Studies
Authors: Al-Kurdi Zakieh , Chowdhry Babur , Leharne Stephen , Al Omari Mahmoud , Badwan Adnan
Published: March 2015

The aim of the work reported herein was to investigate the effect of various low molecular weight chitosans (LMWCs) on the stability of insulin using USP HPLC methods. Insulin was found to be stable in a polyelectrolyte complex (PEC) consisting of insulin and LMWC in the presence of a Tris-buffer at pH 6.5. In the presence of LMWC, the stability of insulin increased with decreasing molecular weight of LMWC; 13 kDa LMWC was the most efficient molecular weight for enhancing the physical and chemical stability of insulin. Solubilization of insulin-LMWC polyelectrolyte complex (I-LMWC PEC) in a reverse micelle (RM) system, administered to diabetic rats, results in an oral delivery system for insulin with acceptable bioactivity.
Morphological and Proteomic Analyses Reveal that Unsaturated Guluronate Oligosaccharide Modulates Multiple Functional Pathways in Murine Macrophage RAW264.7 Cells
Authors: Xu Xu , Bi De-Cheng , Li Chao , Fang Wei-Shan , Zhou Rui , Li Shui-Ming , Chi Lian-Li , Wan Min , Shen Li-Ming
Published: March 2015

Alginate is a natural polysaccharide extracted from various species of marine brown algae. Alginate-derived guluronate oligosaccharide (GOS) obtained by enzymatic depolymerization has various pharmacological functions. Previous studies have demonstrated that GOS can trigger the production of inducible nitric oxide synthase (iNOS)/nitric oxide (NO), reactive oxygen species (ROS) and tumor necrosis factor (TNF)-α by macrophages and that it is involved in the nuclear factor (NF)-κB and mitogen-activated protein (MAP) kinase signaling pathways. To expand upon the current knowledge regarding the molecular mechanisms associated with the GOS-induced immune response in macrophages, comparative proteomic analysis was employed together with two-dimensional electrophoresis (2-DE), matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF/TOF MS) and Western blot verification. Proteins showing significant differences in expression in GOS-treated cells were categorized into multiple functional pathways, including the NF-κB signaling pathway and pathways involved in inflammation, antioxidant activity, glycolysis, cytoskeletal processes and translational elongation. Moreover, GOS-stimulated changes in the morphologies and actin cytoskeleton organization of RAW264.7 cells were also investigated as possible adaptations to GOS. This study is the first to reveal GOS as a promising agent that can modulate the proper balance between the pro- and anti-inflammatory immune responses, and it provides new insights into pharmaceutical applications of polysaccharides.
Flotation Bubble Delineation Based on Harris Corner Detection and Local Gray Value Minima
Authors: Wang Weixing , Chen Liangqin
Published: March 2015

Froth image segmentation is an important and basic part in an online froth monitoring system in mineral processing. The fast and accurate bubble delineation in a froth image is significant for the subsequent froth surface characterization. This paper proposes a froth image segmentation method combining image classification and image segmentation. In the method, an improved Harris corner detection algorithm is applied to classify froth images first. Then, for each class, the images are segmented by automatically choosing the corresponding parameters for identifying bubble edge points through extracting the local gray value minima. Finally, on the basis of the edge points, the bubbles are delineated by using a number of post-processing functions. Compared with the widely used Watershed algorithm and others for a number of lead zinc froth images in a flotation plant, the new method (algorithm) can alleviate the over-segmentation problem effectively. The experimental results show that the new method can produce good bubble delineation results automatically. In addition, its processing speed can also meet the online measurement requirements.
The Absolute Configuration of Salicortin, HCH-Salicortin and Tremulacin from Populus trichocarpa × deltoides Beaupré
Authors: Feistel Felix , Paetz Christian , Lorenz Sybille , Schneider Bernd
Published: March 2015

The absolute configuration of salicortin, HCH-salicortin and tremulacin, isolated from leaves of Populus trichocarpa × deltoides Beaupré, was determined by comparing spectroscopic data of these compounds with those of idescarpin, isolated from leaves of Idesia polycarpa. All compounds were characterized by nuclear magnetic resonance spectroscopy, high-resolution mass spectrometry, and circular dichroism spectroscopy. It was found that the hydroxy cyclohexenonoyl (HCH) moiety in all compounds is (S)-configured. In addition, it was shown that leaves of Idesia polycarpa contain high amounts of (−)-idescarpin (1.1%, based on dry weight).
A Review of Heterogeneous Photocatalysis for Water and Surface Disinfection
Authors: Byrne John , Dunlop Patrick , Hamilton Jeremy , Fernández-Ibáñez Pilar , Polo-López Inmaculada , Sharma Preetam , Vennard Ashlene
Published: March 2015

Photo-excitation of certain semiconductors can lead to the production of reactive oxygen species that can inactivate microorganisms. The mechanisms involved are reviewed, along with two important applications. The first is the use of photocatalysis to enhance the solar disinfection of water. It is estimated that 750 million people do not have accessed to an improved source for drinking and many more rely on sources that are not safe. If one can utilize photocatalysis to enhance the solar disinfection of water and provide an inexpensive, simple method of water disinfection, then it could help reduce the risk of waterborne disease. The second application is the use of photocatalytic coatings to combat healthcare associated infections. Two challenges are considered, i.e., the use of photocatalytic coatings to give “self-disinfecting” surfaces to reduce the risk of transmission of infection via environmental surfaces, and the use of photocatalytic coatings for the decontamination and disinfection of medical devices. In the final section, the development of novel photocatalytic materials for use in disinfection applications is reviewed, taking account of materials, developed for other photocatalytic applications, but which may be transferable for disinfection purposes.
New Flavonolignan Glycosides from the Aerial Parts of Zizania latifolia
Authors: Lee Seung-Su , Baek Nam-In , Baek Yoon-Su , Chung Dae-Kyun , Song Myoung-Chong , Bang Myun-Ho
Published: March 2015

Two new flavonolignan glycosides, tricin-4'-O-(threo-β-guaiacylglyceryl) ether 7''-O-β-D-glucopyranose (4) and tricin-4'-O-(erythro-β-guaiacylglyceryl) ether 7''-O-β-D-glucopyranose (5) were isolated from the roots of Zizania latifolia, together with tricin-7-O-β-D-glucopyranose (1), tricin-4'-O-(threo-β-guaiacylglyceryl) ether 7-O-β-D-glucopyranose (2), and tricin-4'-O-(erythro-β-guaiacylglyceryl) ether 7-O-β-D-glucopyranose (3). Their structures were identified on the basis of spectroscopic techniques, including HR-ESI/MS, 1D-NMR (1H, 13C, DEPT), 2D-NMR (gCOSY, gHSQC, gHMBC), and IR spectroscopy.
Design, Synthesis, and Insecticidal Activity of Some Novel Diacylhydrazine and Acylhydrazone Derivatives
Authors: Sun Jialong , Zhou Yuanming
Published: March 2015

In this study a series of diacylhydrazine and acylhydrazone derivatives were designed and synthesized according to the method of active group combination and the principles of aromatic group bioisosterism. The structures of the novel derivatives were determined on the basis on 1H-NMR, IR and ESI-MS spectral data. All of the compounds were evaluated for their in vivo insecticidal activity against the third instar larvae of Spodoptera exigua Hiibner, Helicoverpa armigera Hubner, Plutella xyllostella Linnaeus and Pieris rapae Linne, respectively, at a concentration of 10 mg/L. The results showed that all of the derivatives displayed high insecticidal activity. Most of the compounds presented higher insecticidal activity against S. exigua than the reference compounds tebufenozide, metaflumizone and tolfenpyrad, and approximately identical insecticidal activity against H. armigera, P. xyllostella and P. rapae as the references metaflumizone and tolfenpyrad.
B Vitamins, Homocysteine and Bone Health
Authors: Fratoni Valentina , Brandi Maria
Published: March 2015

Nutrition is one of the most important modifiable factors involved in the development and maintenance of good bone health. Calcium and Vitamin D have confirmed and established roles in the maintenance of proper bone health. However, other nutritional factors could also be implicated. This review will explore the emerging evidence of the supporting role of certain B Vitamins as modifiable factors associated with bone health. Individuals with high levels of homocysteine (hcy) exhibit reduced bone mineral density (BMD), alteration in microarchitecture and increased bone fragility. The pathophysiology caused by high serum homocysteine is not completely clear regarding fractures, but it may involve factors, such as bone mineral density, bone turnover, bone blood flow and collagen cross-linking. It is uncertain whether supplementation with B Vitamins, such as folate, Vitamin B1, and Vitamin B6, could decrease hip fracture incidence, but the results of further clinical trials should be awaited before a conclusion is drawn.
Block Co-Polymers for Nanolithography: Rapid Microwave Annealing for Pattern Formation on Substrates
Authors: Borah Dipu , Rasappa Sozaraj , Senthamaraikannan Ramsankar , Holmes Justin , Morris Michael
Published: March 2015

The integration of block copolymer (BCP) self-assembled nanopattern formation as an alternative lithographic tool for nanoelectronic device fabrication faces a number of challenges such as defect densities, feature size, pattern transfer, etc. Key barriers are the nanopattern process times and pattern formation on current substrate stack layers such as hard masks (e.g., silicon nitride, Si3N4). We report a rapid microwave assisted solvothermal (in toluene environments) self-assembly and directed self-assembly of a polystyrene-block-polydimethylsiloxane (PS-b-PDMS) BCP thin films on planar and topographically patterned Si3N4 substrates. Hexagonally arranged, cylindrical structures were obtained and good pattern ordering was achieved. Factors affecting BCP self-assembly, notably anneal time and temperature, were studied and seen to have significant effects. Graphoepitaxy within the topographical structures provided long range, translational alignment of the patterns. The effect of surface topography feature size and spacing was investigated. The solvothermal microwave based technique used to provide periodic order in the BCP patterns showed significant promise and ordering was achieved in much shorter periods than more conventional thermal and solvent annealing methods. The implications of the work in terms of manufacturing technologies are discussed.
Multi-Scale Simulation of Hyperbranched Polymers
Authors: Schmidt Ricardo , Hernández Cifre José , De la Torre José
Published: March 2015

In a previous work, we described a multi-scale protocol for the simulation of the conformation and dynamics of macromolecules that was applied to dendrimer molecules proving its predictive capability by comparison with experimental data. That scheme is now employed in order to predict conformational properties (radius of gyration) and overall hydrodynamic properties (translational diffusion and intrinsic viscosity) of hyperbranched molecules in dilute solution. For that purpose, we use a very simple coarse-grained bead-and-spring model whose parameters are not adjusted against experimental properties but they are obtained from previous atomic-level (Langevin) simulations of small fragments of real hyperbranched polymers. In addition, we devise a method to generate structures with different degree of branching. The Monte Carlo simulation technique was used to generate the set conformations of the coarse-grained model. In spite of the difficulties of reproducing experimental data of highly polydisperse entities (in terms of both molecular weight and topology) without using adjustable parameters, the results of this paper show that the proposed methodology allows for qualitative predictions of the behavior of such complex systems and lead us to conclude that, after some improvement, acceptable quantitative predictions can be achieved.