bluuebunny/crossref_metadata_2025 huggingface dataset:
Roles of Alloying Elements on the Passivity of W-xCr-yNi Alloys in Aggressive Environments
Authors: Kharel PL , Sah SP , Bhattarai J
Published: May 2014

The role of alloying elements on the passivity of the sputter−deposited amorphous or nanocrystalline W-xCr-yNi alloys in 12 M HCl, 0.5 M NaCl and 1 M NaOH solutions open to air at 30°C was studied by corrosion tests and electrochemical measurements. All the examined sputter-deposited W-(42-75)Cr-(4-15)Ni alloys, which are composed of either amorphous or nanocrystalline single phase solid solution, showed higher corrosion resistance than those of alloying elements (i.e. tungsten, chromium and nickel) in 12 M HCl, 0.5 M NaCl and 1 M NaOH solutions. All the alloys used in this study showed higher corrosion resistance than those of the alloying elements in the aggressive environments. Anodic current densities of the alloys decreased with increasing chromium contents and became lower than that of chromium. Transpassive dissolution of chromium was significantly enhanced by the simultaneous additions of tungsten, chromium and nickel in aggressive environments of 12 M HCl, 0.5 M NaCl and 1 M NaOH. Hence the synergistic effect of chromium addition in enhancing the corrosion resistance of the W-xCr-yNi alloys was clearly observed from the present study.DOI: http://dx.doi.org/10.3126/njst.v14i2.10418   Nepal Journal of Science and Technology Vol. 14, No. 2 (2013) 65-72
Channel Estimation in MIMO-OFDM System
Authors: Aryal SR , Dhungana H
Published: May 2014

There are no limit of human desire, so day by day we need much higher data speed to facilitate our need but every physical resource like frequency band, transmit signal strength are finite. Within the given limited resource, higher data speed is accomplished by new proficiency called Multiple Input Multiple Output (MIMO), Orthogonal Frequency Division Multiplexing (OFDM) system. MIMO-OFDM fulfills the high data rate requirement through spatial multiplexing gain and improved link reliability due to antenna diversity gain. With this technique, both interference reduction and maximum diversity gain are achieved by increasing number of antennae on either side. Received signal in MIMO-OFDM system is usually distorted by multipath fading. In order to recover the transmitted signal correctly, channel effect must be estimated and repaired at receiver. In this paper the performance evaluating parameter mean square error and symbol error rate of least square error, minimum mean square error and DFT based channel estimation methods are estimated and appropriate solution is recommended. Furthermore, comparison among their characteristics is simulated in MATLAB and useful conclusion is delineated. DOI: http://dx.doi.org/10.3126/njst.v14i2.10421   Nepal Journal of Science and Technology Vol. 14, No. 2 (2013) 97-102
Comparatives Study of Soil Organic Carbon (SOC) under Forest, Cultivated and Barren Land: A Case of Chovar Village, Kathmandu
Authors: Bhandari S , Bam S
Published: May 2014

The study was carried out in Chovar village of Kritipur Municipality, Kathmandu to compare the soil organic carbon (SOC) of three main land use types namely forest, agricultural and barren land and to show how land use and management are among the most important determinants of SOC stock. Stratified random sampling method was used for collecting soil samples. Walkley and Black method was applied for measuring SOC. Land use and soil depth both affected SOC stock significantly. Forest soil had higher SOC stock (98 t ha-1) as compared to agricultural land with 36.6 t ha-1 and barren land with 83.6 t ha-1. Similarly, the SOC in terms of CO22-1, 79.27 to 22.02 CO2-e ha-1 and 121.11 to 80.74 CO2-1 for 0- 20 cm to 40-60 cm soil depth, respectively. Bulk density (BD) was found less in forest soil compared to other lands at all depths, which showed negative correlation with SOC. The study showed a dire need to increase current soil C stocks which can be achieved through improvements in land use and management practices, particularly through conservation and restoration of degraded forests and soils.   DOI: http://dx.doi.org/10.3126/njst.v14i2.10422   Nepal Journal of Science and Technology Vol. 14, No. 2 (2013) 103-108
On Locally Convex Topological Vector Space Valued Paranormed Function Space Defined by Orlicz Function
Authors: Pahari NP
Published: May 2014

The aim of this paper is to introduce and study a new class (l∞ (X, Y, Φ, ξ, w , L), HU) of locally convex space Y- valued functions using Orlicz function Φ as a generalization of some of the well known sequence spaces and function spaces. Besides the investigation pertaining to the linear topological structures of the class (l∞ (X, Y, Φ, ξ, w , L), HU) when topologized it with suitable natural paranorm , our primarily interest is to explore the conditions pertaining the containment relation of the class l∞ (X, Y, Φ, ξ, w) in terms of different ξ and w so that such a class of functions is contained in or equal to another class of similar nature. DOI: http://dx.doi.org/10.3126/njst.v14i2.10423   Nepal Journal of Science and Technology Vol. 14, No. 2 (2013) 109-116
Production, Purification and Characterization of Hemicellulose from Penicillium janthinellum 3CHP
Authors: Adhikari S , Chadha BS
Published: May 2014

Penicillium janthinellum 3CHP, a mesophilic fungal strain, isolated from the pine forest of Simla hill was found to produce an array of hemicelluloses when grown in urea medium with sorghum straw as the carbon source. For purification these enzymes, were subjected to ion exchange chromatography. The active fractions pertaining to á-arabinofuranosidase obtained from it were pooled and concentrated using PM-10 (10 KDa cut off) fitted into an Amicon cell and further purified by gel filtration chromatography. Active fractions which exhibited high á-arabinofuranosidase activity in gel filtration chromatography were again pooled, concentrated and analyzed by SDS PAGE and zymogram development using L-umbelliferyl arabinofuranoside as substrate. Two isoforms of á-arabinofuranosidase were observed with molecular weight of approximately 60 and 80 KDa respectively. á-arabinofuranosidase, was further characterized with respect to various parameters such as temperature, pH, effect of various metal ions and chemicals, substrate specificity, and thermo-stability DOI: http://dx.doi.org/10.3126/njst.v14i2.10425   Nepal Journal of Science and Technology Vol. 14, No. 2 (2013) 123-130
Staphylococcal Colonisation of Intravenous Cannula and Antimicrobial Patterns of Isolated Staphylococcus Species
Authors: Mahto R , Amatya J , Amatya R , Adhikari D
Published: May 2014

Cannula-related infections are amongst the most important nosocomial infections. Staphylococcus aureus and coagulase negative Staphylococci (CONS) are the most frequent causes of colonizing the intravenous cannula through which infection may occur. The aim of the study was to isolate the colonized staphylococci and to study the antimicrobial sensitivity pattern against them. Cultures of cannula tips were raised by semi-quantitative method. Antibiotic susceptibility test was performed by Kirby Bauer disc diffusion method as per The Clinical and Laboratory Standard Institute (CLSI) guidelines. Coagulase positive Staphylococcus was confirmed by coagulase slide test followed by tube test. CONS were distinguished by novobiocin sensitivity test. Out of 200 samples of cannula tips collected and processed, 45 (22.5%) isolates were S. aureus, 15 (7.5%) were S. epidermidis and 16 (8%) were other CONS. The highest occurance (30.7%) of S. aureus and the CONS (18.4%) was found in the nephrology ward and the surgical ward respectively. All the 76 isolates were tested for antimicrobial susceptibility pattern. Novobiocin was used to differentiate S. epidermidis from other CONS. All isolates were sensitive to ampicillin and ofloxacin. Out of total, 46.7% isolates of S. aureus and 12.9% isolates of CONS were multidrug resistant; 35.5% and 20 % isolates of S. aureus were oxacillin (methicillin) resistant and vancomycin resistant respectively. Four (12.9%) isolates of CONS [2(13.3%) of other CONS and 2(12.5%) of S. epidermidis] were oxacillin (methicillin) and vancomycin resistant. In our study, vancomycin resistant staphylococci were found and it was concluded that the precautions for inserting intravenous cannula is necessary as different kinds of pathogens may colonize such devices. DOI: http://dx.doi.org/10.3126/njst.v14i2.10426   Nepal Journal of Science and Technology Vol. 14, No. 2 (2013) 131-136
Identification of β-Haemolytic Streptococci among Pharyngitis Cases at Bir Hospital, Kathmandu
Authors: Shrestha AK , Lekhak B , Shrestha J , Bhatta DR
Published: May 2014

Respiratory tract infection is one of the major reasons of patients seeking medical care. Among infections pharangitis is most common in the upper respiratory tract, which is seen most frequently in children and adolescents and less frequently among adults. The objective of this study was to analyze the underlying bacterial pathogens in pharyngitis cases and antibiotic susceptibility of various isolates. During February to August, 2010, a total of 134 patients visiting E.N.T. OPD of Bir Hospital complaining sore throat were studied. The throat swabs of the patients were cultured in 5.0% sheep blood agar plates and incubated at 37°C for 24-48 hrs. Clear transparent β-haemolytic colonies of the germs were selected and identified. Group A streptococcus was identified by β-haemolytic colonies with bacitracin and penicillin sensitivity, gram staining, catalase negativity and growth on crystal violet blood agar. In this study, 23 (17.2%) patients were positive for β-haemolytic streptococci. Among them, 12 (9%) were identified as Group A streptococcus. The culture positive for BHS was highest (56.5%) among the age group of 21-40 years. Pathogens other than β-haemolytic streptococci were isolated from 9 patients, of which 4 cases showed mixed bacterial growth. Other bacterial isolates reported in the study were Staphylococcus aureus 6 (4.5%), Klebsiella pneumoniae 5 (3.7%), Pseudomonas aeruginosa 2 (1.5%), Citrobacter freundii 1 (0.7%), and yeast cells 1 (0.7%). It was found that infections caused by β-haemolytic streptococci was significantly higher p=0.0084 i.e. (p<0.05) than infections caused by other bacteria. This study demonstrated that young adults of age group 21-40 were affected by streptococcal pharyngitis. The isolates of GAS were 100% sensitive to amoxycillin, cephalexin, cefotaxime, ciprofloxacin and azithromycin followed by cotrimoxazole (91.7%) and erythromycin (91.7%). DOI: http://dx.doi.org/10.3126/njst.v14i2.10427 Nepal Journal of Science and Technology Vol. 14, No. 2 (2013) 137-142
Anti-oxidative Activity of Nepalese Traditional Anti-diabetic Medicines
Authors: Devkota HP , Adhikari-Devkota A , Yahara S , Basnet P
Published: May 2014

Chronic overproduction of free radicals in human body has a role in numerous disease states including diabetes. Proper use of antioxidants may help in the prevention and/or treatment of diabetes. For the management of diabetes, a combination of herbal drugs is being practiced traditionally in Nepal. These herbal medicines might have a good correlation to anti-oxidative properties. Anti-oxidative property was evaluated with the methanolic extracts of nineteen common traditional anti-diabetic medicines by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging method. Among the evaluated herbal medicines, Phyllanthus emblica, Punica granatum, Syzygium cumini, Terminalia bellirica and Terminalia chebula showed potent radical scavenging activity. The activities of P. emblica, T. bellirica and T. chebula were more potent than that of ascorbic acid. Some of the reported popular hypoglycemic herbal drugs did not show strong activity. Therefore strong anti-oxidative herbal drugs in combination with hypoglycemic drugs might have better results in the management of diabetes. DOI: http://dx.doi.org/10.3126/njst.v14i2.10429   Nepal Journal of Science and Technology Vol. 14, No. 2 (2013) 151-154
Morphology and AFM Spectroscopy of Irradiated Interface of Silicon
Authors: Lamichhane SK
Published: May 2014

In covalent solids, more energetic irradiation sources are necessary to produce detectable level of damage. The atomic force microscopic (AFM) studies of mega electron-volt (MeV) ions irradiated silicon surfaces have been studied to a fluence of 5×108 ions cm-2 and surface morphology has been studied with AFM. Interesting features of cracks of ~ 50 nm in depth and ~ 100 nm in width have been observed on the irradiated surface. The features seemed to have been caused by the irradiation-induced stress in the irradiated regions of the target surface. The observed feature of cracks seems to be mainly due to the high electronic energy loss of the irradiated ions on the surface induces the stress in it. It confirms that the coarseness of the microstructure of a material directly affects the mechanical properties. DOI: http://dx.doi.org/10.3126/njst.v14i2.10430   Nepal Journal of Science and Technology Vol. 14, No. 2 (2013) 155-160
TBHP-Mediated C–H Thiolation of Tetrahydrofuran with Disulfides Promoted by Catalytic Amounts of Na2CO3
Authors: Tao Li-Ming , Liu Wen-Qi , Li Chuan-Hua , Liu Hui
Published: May 2014

An efficient route to constructing C–S bonds has been developed by TBHP ( tert-butyl hydroperoxide) mediated C–H thiolation of tetrahydrofuran with disulfides. This route is promoted by catalytic amounts of Na2CO3 and gives various tetrahydrofuran-containing sulfides in moderate to high yields.
A Facile Synthesis of Dispiro[indole-3,2′-Pyrrolidine-3,5″-[1,3]Thiazolane] Derivatives from 2,3,5-Trisubstituted-4-Thiazolidinones via 1,3-Dipolar Cycloaddition Reaction
Authors: Feng Guo-Liang , Zhang Hong-Li , Geng Li-Jun
Published: May 2014

A series of 2″,3″,4′-triaryl-1′-methyldispiro[indole-3,2′-pyrrolidine-3′,5″-[1,3]thiazolane]-2(1 H),4″-dione derivatives were successfully synthesised via a three-component 1,3-dipolar cycloaddition reaction of 2,3,5-trisubstituted-4-thiazolidinones, isatin and sarcosine in refluxing toluene. Such a strategy would provide access to a fast one-pot synthesis of spiroheterocycle in high yields.
Microwave-Assisted Synthesis and in Vitro Antibacterial Activity of Novel Steroidal 1,2,4-Triazole Schiff Base Derivatives
Authors: Xingli Xiaohong Wang , Jiang Liu Yujia , Zhao Zhigang
Published: May 2014

A series of novel Schiff bases containing both a 1,2,4-triazole and deoxycholic acid skeleton have been synthesised in excellent yields and in high purity by means of microwave irradiation. The structures of the target compounds were characterised by MS, IR and NMR as well as elemental analysis. All the products were evaluated for their in vitro antibacterial activities against Gram positive ( Staphylococcus aureus and Bacillus subtilis) and Gram negative bacteria ( Pseudomonas seruginosa and Escherichia coli). Four of the compounds displayed varying levels of antibacterial activity against P. aeruginosa and S. aureus, but none of the compounds showed any activity against E. coli and B. subtilis.
Recoverable autonomous sonde (RECAS) for environmental exploration of Antarctic subglacial lakes: general concept
Authors: Talalay P.G. , Zagorodnov V.S. , Markov A.N. , Sysoev M.A. , Hong J.
Published: May 2014

The proposed RECoverable Autonomous Sonde (RECAS) will allow analysis and sampling of subglacial water while the subglacial lake remains isolated from the surface. The probe is equipped with two electrically heated melting tips, one on the bottom and one on the top of a cylindrical probe. When one of the tips is powered, the RECAS moves up or down similarly to a hot-point thermal electric drill. The electric power and signal cable is coiled inside the probe on an electric-motor-powered coil. When the lower tip is powered, the probe advances downwards by gravity. In order to move the probe up, power is applied to the upper heated tip and the coil motor pulls the cable, moving the probe upwards and melting the borehole above the probe. A conventional internal combustion engine electric generator on the glacier surface provides 9–10 kW of power to the RECAS via an umbilical cable stored in the probe. Electric power enables a penetration rate of 2.4–2.9m h–1, and thus 4–5 months will be required to reach a depth of 3500 m and return to the surface.
Geometric sensitivity of statically determinate planar truss families
Authors: Tóth Krisztina
Published: May 2014

We define a truss family Ti by a statically determinate truss T0 and a recursive step Ti+1=f(Ti), such that Ti+1Ti and that step  f(Ti) keeps static determinacy. Such recursive algorithms have been broadly discussed in the literature, e.g. the Henneberg operation 1 is a well-known example. Earlier we introduced the concept of geometric sensitivity index rg of trusses, here we investigate the sensitivity of truss families, in particular, the limit sensitivity ﻿(Ti).
The Arch Of Projection - Body and Mind in Herzog & de Meuron’s Architecture
Authors: Simon Mariann
Published: May 2014

The aim of the article is to interpret the body-mind relationship in Herzog & de Meuron’s architecture. We surveyed their architecture over the last twenty years, uncovering the parallel changes in buildings and writings, with the theoretical trends in the background. We found that a clear shift in their approach has been manifest. In the first phase, the architects’ bodily and intellectual sensations were mediated through the building, whose subtle deviations from architectonic rules were perceivable more to the senses than to the mind. In the second period, the sensuality of buildings increased, while intellectually they referred to the present. The buildings still had their integral body, but they had lost a clear contour. In the last decade, the buildings operate with an arsenal of material and sensuous effects; the aim is intensity, which is often reinforced with direct formal analogies. The body of the visitor is put centre stage.
Hydrogen Spectral Line Shape Formation in the SOL of Fusion Reactor Plasmas
Authors: Lisitsa Valery , Kadomtsev Mikhail , Kotov Vladislav , Neverov Vladislav , Shurygin Vladimir
Published: May 2014

The problems related to the spectral line-shape formation in the scrape of layer (SOL) in fusion reactor plasma for typical observation chords are considered. The SOL plasma is characterized by the relatively low electron density (1012–1013 cm−3) and high temperature (from 10 eV up to 1 keV). The main effects responsible for the line-shape formation in the SOL are Doppler and Zeeman effects. The main problem is a correct modeling of the neutral atom velocity distribution function (VDF). The VDF is determined by a number of atomic processes, namely: molecular dissociation, ionization and charge exchange of neutral atoms on plasma ions, electron excitation accompanied by the charge exchange from atomic excited states, and atom reflection from the wall. All the processes take place step by step during atom motion from the wall to the plasma core. In practice, the largest contribution to the neutral atom radiation emission comes from a thin layer near the wall with typical size 10–20 cm, which is small as compared with the minor radius of modern devices including international test experimental reactor ITER (radius 2 m). The important problem is a strongly non-uniform distribution of plasma parameters (electron and ion densities and temperatures). The distributions vary for different observation chords and ITER operation regimes. In the present report, most attention is paid to the problem of the VDF calculations. The most correct method for solving the problem is an application of the Monte Carlo method for atom motion near the wall. However, the method is sometimes too complicated to be combined with other numerical codes for plasma modeling for various regimes of fusion reactor operation. Thus, it is important to develop simpler methods for neutral atom VDF in space coordinates and velocities. The efficiency of such methods has to be tested via a comparison with the Monte Carlo codes for particular plasma conditions. Here a new simplified method for description of neutral atoms penetration into plasma is suggested. The method is based on the ballistic motion of neutrals along the line-of-sight (LoS) in the forward–back approximation. As a result, two-dimensional distribution functions, dependent on the LoS coordinate and the velocity projection on the LoS, and responsible for the Doppler broadening of the line shape, are calculated. A comparison of the method with Monte Carlo calculations allows the evaluation of the accuracy of the ballistic model. The Balmer spectral line shapes are calculated for specific LoS typical for ITER diagnostics.
Validation and Implementation of Uncertainty Estimates of Calculated Transition Rates
Authors: Ekman Jörgen , Godefroid Michel , Hartman Henrik
Published: May 2014

Uncertainties of calculated transition rates in LS-allowed electric dipole transitions in boron-like O IV and carbon-like Fe XXI are estimated using an approach in which differences in line strengths calculated in length and velocity gauges are utilized. Estimated uncertainties are compared and validated against several high-quality theoretical data sets in O IV, and implemented in large scale calculations in Fe XXI.
Characteristic Number: Theory and Its Application to Shape Analysis
Authors: Fan Xin , Luo Zhongxuan , Zhang Jielin , Zhou Xinchen , Jia Qi , Luo Daiyun
Published: May 2014

Geometric invariants are important for shape recognition and matching. Existing invariants in projective geometry are typically defined on the limited number (e.g., five for the classical cross-ratio) of collinear planar points and also lack the ability to characterize the curve or surface underlying the given points. In this paper, we present a projective invariant named after the characteristic number of planar algebraic curves. The characteristic number in this work reveals an intrinsic property of an algebraic hypersurface or curve, which relies no more on the existence of the surface or curve as its planar version. The new definition also generalizes the cross-ratio by relaxing the collinearity and number of points for the cross-ratio. We employ the characteristic number to construct more informative shape descriptors that improve the performance of shape recognition, especially when severe affine and perspective deformations occur. In addition to the application to shape recognition, we incorporate the geometric constraints on facial feature points derived from the characteristic number into facial feature matching. The experiments show the improvements on accuracy and robustness to pose and view changes over the method with the collinearity and cross-ratio constraints.
Synthesis of a Virtual Urban Soundscape
Authors: Rychtáriková Monika , Jedovnický Martin , Vargová Andrea , Glorieux Christ
Published: May 2014

The main research question addressed in this article is to find out to what extent it is possible to predict statistical noise levels such as L5 and L95 on an urban public square, based on the information about the square’s functionality, the activities going on, and the architecture of the surrounding buildings. The same information is also exploited to auralize the soundscape on the virtual square, in order to assess the disturbance perceived by people of the traffic noise by means of laboratory listening tests, which are based on binaural sound recordings acquired in situ and incorporated in simulations to evoke typical acoustical situations. Auralizations were carried out by two calculation algorithms (ray-tracing and image source method) and two acoustic scenarios (an anechoic situation and a virtually reconstructed square in Odeon®). The statistical noise levels, calculated from the auralized soundscapes, compare well with measurements in situ. The listening test results also show that there are significant differences in people’s perception of traffic noise, depending on their origin.
Structures and Magnetic Properties of Iron(III) Complexes with Long Alkyl Chains
Authors: Nakaya Manabu , Shimayama Kodai , Takami Kohei , Hirata Kazuya , Amolegbe Saliu , Nakamura Masaaki , Lindoy Leonald , Hayami Shinya
Published: May 2014

Iron(III) compounds with long alkyl chains, [Fe(Cn-pap)2]ClO4 (Cn-pap: alkoxy-2-(2-pyridylmethyleneamino)phenol, n = 8 (1), 10 (2), 12 (3), 14 (4), 16 (5)) have been synthesized. The compounds were characterized by single crystal X-ray structure analysis and temperature dependent magnetic susceptibility in order to research the relationship between magnetic properties and the presence of long alkyl chains in soft molecules of the present type. The compounds 1, 2, 3 and 4 are in the high-spin (HS) state over the temperature range of 5 to 400 K. On the other hand, compound 5 is low-spin (LS) showing that the difference in magnetic properties depends on the length of the alkyl chain in the respective compounds.
Effect of Radio Frequency Heating on Yoghurt, I: Technological Applicability, Shelf-Life and Sensorial Quality
Authors: Siefarth Caroline , Tran Thi , Mittermaier Peter , Pfeiffer Thomas , Buettner Andrea
Published: May 2014

This first part of a two-part study focuses on the technical feasibility of applying radio frequency (RF) heating at different temperatures (58, 65 and 72 °C) to a stirred yoghurt gel after culturing. For comparison, a convectional (CV) heating process was also applied. The aim was to increase the yoghurt shelf-life, by preventing post-acidification and the growth of yeasts and molds. At the same time, the viability of lactic acid bacteria (LAB) was investigated in view of existing legal regulations for yoghurts. Additionally, the yoghurt color, aroma and taste profiles were evaluated. It was found that the application of RF heating was effective for the rapid attainment of homogenous temperatures of 58 and 65 °C, respectively. For RF heating at 72 °C, it was not possible to establish a stable heating regime, since in some cases, there was significant overheating followed by strong contraction of the yoghurt curd and whey separation. Hence, it was decided not to continue with the RF heating series at 72 °C. In the case of CV heating, heat transfer limitations were observed, and prolonged heating was required. Nevertheless, we showed that yeasts and molds survived neither the RF nor CV heat treatment. LAB were found not to survive the CV treatment, but these beneficial microorganisms were still present in reduced numbers after RF heating to 58 and 65 °C. This important observation is most likely related to the mildness of RF treatment. While post-acidification was not observed on yoghurt storage, slight color changes occurred after heat treatment. The flavor and taste profiles were shown to be similar to the reference product. Furthermore, a trained sensory panel was not able to distinguish between, for example, the reference yoghurt and the RF 65 °C sample by triangular testing (α = 5%), showing the potential of novel strategies for further improvements of heat-treated yoghurt.
Signaling Pathways in Cartilage Repair
Authors: Mariani Erminia , Pulsatelli Lia , Facchini Andrea
Published: May 2014

In adult healthy cartilage, chondrocytes are in a quiescent phase characterized by a fine balance between anabolic and catabolic activities. In ageing, degenerative joint diseases and traumatic injuries of cartilage, a loss of homeostatic conditions and an up-regulation of catabolic pathways occur. Since cartilage differentiation and maintenance of homeostasis are finely tuned by a complex network of signaling molecules and biophysical factors, shedding light on these mechanisms appears to be extremely relevant for both the identification of pathogenic key factors, as specific therapeutic targets, and the development of biological approaches for cartilage regeneration. This review will focus on the main signaling pathways that can activate cellular and molecular processes, regulating the functional behavior of cartilage in both physiological and pathological conditions. These networks may be relevant in the crosstalk among joint compartments and increased knowledge in this field may lead to the development of more effective strategies for inducing cartilage repair.
Carbon Nanofibers and Their Composites: A Review of Synthesizing, Properties and Applications
Authors: Feng Lichao , Xie Ning , Zhong Jing
Published: May 2014

Carbon nanofiber (CNF), as one of the most important members of carbon fibers, has been investigated in both fundamental scientific research and practical applications. CNF composites are able to be applied as promising materials in many fields, such as electrical devices, electrode materials for batteries and supercapacitors and as sensors. In these applications, the electrical conductivity is always the first priority need to be considered. In fact, the electrical property of CNF composites largely counts on the dispersion and percolation status of CNFs in matrix materials. In this review, the electrical transport phenomenon of CNF composites is systematically summarized based on percolation theory. The effects of the aspect ratio, percolation backbone structure and fractal characteristics of CNFs and the non-universality of the percolation critical exponents on the electrical properties are systematically reviewed. Apart from the electrical property, the thermal conductivity and mechanical properties of CNF composites are briefly reviewed, as well. In addition, the preparation methods of CNFs, including catalytic chemical vapor deposition growth and electrospinning, and the preparation methods of CNF composites, including the melt mixing and solution process, are briefly introduced. Finally, their applications as sensors and electrode materials are described in this review article.
Biotechnological Screening of Microalgal and Cyanobacterial Strains for Biogas Production and Antibacterial and Antifungal Effects
Authors: Mudimu Opayi , Rybalka Nataliya , Bauersachs Thorsten , Born Jens , Friedl Thomas , Schulz Rüdiger
Published: May 2014

Microalgae and cyanobacteria represent a valuable natural resource for the generation of a large variety of chemical substances that are of interest for medical research, can be used as additives in cosmetics and food production, or as an energy source in biogas plants. The variety of potential agents and the use of microalgae and cyanobacteria biomass for the production of these substances are little investigated and not exploited for the market. Due to the enormous biodiversity of microalgae and cyanobacteria, they hold great promise for novel products. In this study, we investigated a large number of microalgal and cyanobacterial strains from the Culture Collection of Algae at Göttingen University (SAG) with regard to their biomass and biogas production, as well antibacterial and antifungal effects. Our results demonstrated that microalgae and cyanobacteria are able to generate a large number of economically-interesting substances in different quantities dependent on strain type. The distribution and quantity of some of these components were found to reflect phylogenetic relationships at the level of classes. In addition, between closely related species and even among multiple isolates of the same species, the productivity may be rather variable.
Human Growth Hormone Delivery with a Microneedle Transdermal System: Preclinical Formulation, Stability, Delivery and PK of Therapeutically Relevant Doses
Authors: Ameri Mahmoud , Kadkhodayan Miryam , Nguyen Joe , Bravo Joseph , Su Rebeca , Chan Kenneth , Samiee Ahmad , Daddona Peter
Published: May 2014

This study evaluated the feasibility of coating formulated recombinant human growth hormone (rhGH) on a titanium microneedle transdermal delivery system, Zosano Pharma (ZP)-hGH, and assessed preclinical patch delivery performance. Formulation rheology and surface activity were assessed by viscometry and contact angle measurement. rhGH liquid formulation was coated onto titanium microneedles by dip-coating and drying. The stability of coated rhGH was determined by size exclusion chromatography-high performance liquid chromatography (SEC-HPLC). Preclinical delivery and pharmacokinetic studies were conducted in female hairless guinea pigs (HGP) using rhGH coated microneedle patches at 0.5 and 1 mg doses and compared to Norditropin® a commercially approved rhGH subcutaneous injection. Studies demonstrated successful rhGH formulation development and coating on microneedle arrays. The ZP-hGH patches remained stable at 40 °C for six months with no significant change in % aggregates. Pharmacokinetic studies showed that the rhGH-coated microneedle patches, delivered with high efficiency and the doses delivered indicated linearity with average Tmax of 30 min. The absolute bioavailability of the microneedle rhGH patches was similar to subcutaneous Norditropin® injections. These results suggest that ZP-transdermal microneedle patch delivery of rhGH is feasible and may offer an effective and patient-friendly alternative to currently marketed rhGH injectables.
Learning for a Sustainable Economy: Teaching of Green Competencies in the University
Authors: Murga-Menoyo Mª
Published: May 2014

This paper looks at universities as training centers for a sustainable economy. Their remit is to promote the required competencies to achieve that aim, including competencies in sustainability. This article describes the role that the universities in Spain are fulfilling with respect to these issues and presents a training proposal that comprises four key competencies in sustainability with their corresponding performance indicators that permit the evaluation of different levels of achievement in training processes. These competencies must embrace their formative role not only with regard to future graduates who will be employed in “green jobs” per se, but also with regard to those alumni who will work in all the other productive sectors, in addition to all citizens directly and indirectly involved in the wider economy as consumers, producers and (direct or indirect) recipients of its effects. The proposal is based on the recommendations of the Conferencia de Rectores de Universidades Españolas (CRUE: Conference of Chancellors of Spanish Universities), and can be adapted to the teaching programs of different subjects in order to facilitate the training necessary in general competencies of sustainability within the ambit of the subjects taught. Furthermore, this proposal follows the institutional strategy of CRUE to promote curricula sustainability through the inclusion of the principles and values of sustainable development in every degree and educational program taught. This proposal could also be applied to other cultural contexts with similar characteristics.
Synthesis of zearalenone-16-β,D-glucoside and zearalenone-16-sulfate: A tale of protecting resorcylic acid lactones for regiocontrolled conjugation
Authors: Mikula Hannes , Weber Julia , Svatunek Dennis , Skrinjar Philipp , Adam Gerhard , Krska Rudolf , Hametner Christian , Fröhlich Johannes
Published: May 2014

The development of a reliable procedure for the synthesis of the 16-glucoside and 16-sulfate of the resorcylic acid lactone (RAL) type compound zearalenone is presented. Different protective group strategies were considered and applied to enable the preparation of glucosides and sulfates that are difficult to access up to now. Acetyl and p-methoxybenzyl protection led to undesired results and were shown to be inappropriate. Finally, triisopropylsilyl-protected zearalenone was successfully used as intermediate for the first synthesis of the corresponding mycotoxin glucoside and sulfate that are highly valuable as reference materials for further studies in the emerging field of masked mycotoxins. Furthermore, high stability was observed for aryl sulfates prepared as tetrabutylammonium salts. Overall, these findings should be applicable for the synthesis of similar RAL type and natural product conjugates.
GEOFILTRATION STUDIES OF CLAY AT THE FUTURE RADIOACTIVE WASTE REPOSITORY FOR IGNALINA NUCLEAR POWER PLANT
Authors: Klizas Petras
Published: May 2014

Clay geofiltration studies became important in Lithuania when the clays began to be used as geofiltration barriers for waste disposal sites/repositories. The clay is planned to be used also in construction of the future radioactive waste repository for the Ignalina Nuclear Power Plant. The results of investigation on Stabatiškė subformation till clay occurring at the base of the repository are given in the paper. The investigation has been performed with the purpose to determine potential dependence of clay filtration coefficient values on the number of freeze-thaw cycles and duration of filtration. The filtration coefficient for the repository till clay has been found to be greatly varying at the start of the filtration and during the experiment that lasted several days. This confirms that, during the filtration, structural changeover of clay-forming aggregates takes place with pore space volumes changing and affecting the filtration coefficient values. The filtration parameters are even more affected by freeze-thaw cycles and their number. When the clay thaw is finished the colmatation of fissure system is very slow and incomplete.
Guide to the Vascular Flora of the Savannas and Flatwoods of Shaken Creek Preserve and Vicinity (Pender & Onslow Counties, North Carolina, U.S.A.)
Authors: Thornhill Robert , Krings Alexander , Lindbo David , Stucky Jon
Published: May 2014

Shaken Creek Preserve (“SCP”) is a 2,448 ha (6,050 ac) natural area in Pender and Onslow Counties, North Carolina (U.S.A). Best known for its high-quality longleaf pine savanna habitat, the site contains seven savanna or savanna-like plant community types (i.e., flatwoods or sandhills), three of which are globally critically imperiled (G1): Sandy Pine Savanna (Rush Featherling subtype), Wet Loamy Pine Savanna, and Very Wet Loamy Pine Savanna. SCP hosts three Federally Endangered plant species and six Federal Species of Concern. Formerly a private hunting club, the site was virtually unknown to scientists until the 1990s; consequently, few biological inventories of SCP have been conducted. In particular, no systematic floristic inventories of the species-rich savannas have been undertaken, despite the fact that floristic data is critical to the effective management of any natural area. The goals of this study were to (1) inventory the vascular flora of the savannas, flatwoods, and sandhill community types on site through the collection of voucher specimens; (2) provide a comprehensive checklist of the flora based on collections and reports made from the site and from the same or similar habitats in the vicinity (i.e., within 2 miles of SCP); and (3) create an illustrated guide based on the checklist. In order to increase the usefulness of the guide, taxa not currently known from SCP but collected or reported from the same or similar habitats within two miles of SCP, are included in the guide. Eighty-three families containing 450 taxa, including thirty-two Significantly Rare and thirty-eight Watch List taxa, were collected or reported from SCP; an additional seven families containing a total of 102 taxa, including eighteen Significantly Rare and seven Watch List taxa, were collected or reported from the vicinity. In total, ninety families containing 552 taxa, including fifty Significantly Rare and forty-five Watch List taxa, are treated in the guide. Dichotomous keys are provided to all vouchered or reported families, genera, and species. The following features are provided for all species and infraspecific taxa: flowering and fruiting phenology; synonymy with Manual of the Vascular Flora of the Carolinas, the Flora of North America, and Flora of the Southern and Mid-Atlantic States; relevant voucher information; and, for most taxa, line drawings and/or photographs. For taxa collected from SCP, community types in which the taxa occur and estimates of abundance on site are also provided.
Antigen Delivery to CD11c+CD8− Dendritic Cells Induces Protective Immune Responses against Experimental Melanoma in Mice In Vivo
Authors: Neubert Kirsten , Lehmann Christian H. K. , Heger Lukas , Baranska Anna , Staedtler Anna Maria , Buchholz Veit R. , Yamazaki Sayuri , Heidkamp Gordon F. , Eissing Nathalie , Zebroski Henry , Nussenzweig Michel C. , Nimmerjahn Falk , Dudziak Diana
Published: May 2014

Dendritic cells (DCs) are central modulators of immune responses and, therefore, interesting target cells for the induction of antitumor immune responses. Ag delivery to select DC subpopulations via targeting Abs to DC inhibitory receptor 2 (DCIR2, clone 33D1) or to DEC205 was shown to direct Ags specifically to CD11c+CD8− or CD11c+CD8+ DCs, respectively, in vivo. In contrast to the increasing knowledge about the induction of immune responses by efficiently cross-presenting CD11c+CD8+ DCs, little is known about the functional role of Ag-presenting CD11c+CD8− DCs with regard to the initiation of protective immune responses. In this study, we demonstrate that Ag targeting to the CD11c+CD8− DC subpopulation in the presence of stimulating anti-CD40 Ab and TLR3 ligand polyinosinic-polycytidylic acid induces protective responses against rapidly growing tumor cells in naive animals under preventive and therapeutic treatment regimens in vivo. Of note, this immunization protocol induced a mixed Th1/Th2-driven immune response, irrespective of which DC subpopulation initially presented the Ag. Our results provide important information about the role of CD11c+CD8− DCs, which have been considered to be less efficient at cross-presenting Ags, in the induction of protective antitumor immune responses.
IL-36 Promotes Myeloid Cell Infiltration, Activation, and Inflammatory Activity in Skin
Authors: Foster Alexander M. , Baliwag Jaymie , Chen Cynthia S. , Guzman Andrew M. , Stoll Stefan W. , Gudjonsson Johann E. , Ward Nicole L. , Johnston Andrew
Published: May 2014

The IL-1 family members IL-36α (IL-1F6), IL-36β (IL-1F8), and IL-36γ (IL-1F9) and the receptor antagonist IL-36Ra (IL-1F5) constitute a novel signaling system that is poorly understood. We now show that these cytokines have profound effects on the skin immune system. Treatment of human keratinocytes with IL-36 cytokines significantly increased the expression of CXCL1, CXCL8, CCL3, CCL5, and CCL20, potent chemotactic agents for activated leukocytes, and IL-36α injected intradermally resulted in chemokine expression, leukocyte infiltration, and acanthosis of mouse skin. Blood monocytes, myeloid dendritic cells (mDC), and monocyte-derived DC (MO-DC) expressed IL-36R and responded to IL-36. In contrast, no direct effects of IL-36 on resting or activated human CD4+ or CD8+ T cells, or blood neutrophils, could be demonstrated. Monocytes expressed IL-1A, IL-1B, and IL-6 mRNA and IL-1β and IL-6 protein, and mDC upregulated surface expression of CD83, CD86, and HLA-DR and secretion of IL-1β and IL-6 after treatment with IL-36. Furthermore, IL-36α–treated MO-DC enhanced allogeneic CD4+ T cell proliferation, demonstrating that IL-36 can stimulate the maturation and function of DC and drive T cell proliferation. These data indicate that IL-36 cytokines actively propagate skin inflammation via the activation of keratinocytes, APC, and, indirectly, T cells.
Boosting of HIV-1 Neutralizing Antibody Responses by a Distally Related Retroviral Envelope Protein
Authors: Uchtenhagen Hannes , Schiffner Torben , Bowles Emma , Heyndrickx Leo , LaBranche Celia , Applequist Steven E. , Jansson Marianne , De Silva Thushan , Back Jaap Willem , Achour Adnane , Scarlatti Gabriella , Fomsgaard Anders , Montefiori David , Stewart-Jones Guillaume , Spetz Anna-Lena
Published: May 2014

Our knowledge of the binding sites for neutralizing Abs (NAb) that recognize a broad range of HIV-1 strains (bNAb) has substantially increased in recent years. However, gaps remain in our understanding of how to focus B cell responses to vulnerable conserved sites within the HIV-1 envelope glycoprotein (Env). In this article, we report an immunization strategy composed of a trivalent HIV-1 (clade B envs) DNA prime, followed by a SIVmac239 gp140 Env protein boost that aimed to focus the immune response to structurally conserved parts of the HIV-1 and simian immunodeficiency virus (SIV) Envs. Heterologous NAb titers, primarily to tier 1 HIV-1 isolates, elicited during the trivalent HIV-1 env prime, were significantly increased by the SIVmac239 gp140 protein boost in rabbits. Epitope mapping of Ab-binding reactivity revealed preferential recognition of the C1, C2, V2, V3, and V5 regions. These results provide a proof of concept that a distally related retroviral SIV Env protein boost can increase pre-existing NAb responses against HIV-1.
Novel Role for Tumor-Induced Expansion of Myeloid-Derived Cells in Cancer Cachexia
Authors: Cuenca Alex G. , Cuenca Angela L. , Winfield Robert D. , Joiner Dallas N. , Gentile Lori , Delano Matthew J. , Kelly-Scumpia Kindra M. , Scumpia Philip O. , Matheny Michael K. , Scarpace Philip J. , Vila Lizette , Efron Philip A. , LaFace Drake M. , Moldawer Lyle L.
Published: May 2014

Cancer progression is associated with inflammation, increased metabolic demand, infection, cachexia, and eventually death. Myeloid-derived suppressor cells (MDSCs) commonly expand during cancer and are associated with adaptive immune suppression and inflammatory metabolite production. We propose that cancer-induced cachexia is driven at least in part by the expansion of MDSCs. MDSC expansion in 4T1 mammary carcinoma-bearing hosts is associated with induction of a hepatic acute-phase protein response and altered host energy and fat metabolism, and eventually reduced survival to polymicrobial sepsis and endotoxemia. Similar results are also seen in mice bearing a Lewis lung carcinoma and a C26 colon adenocarcinoma. However, a similar cachexia response is not seen with equivalent growth of the 66C4 subclone of 4T1, in which MDSC expansion does not occur. Importantly, reducing MDSC numbers in 4T1-bearing animals can ameliorate some of these late responses and reduce susceptibility to inflammation-induced organ injury and death. In addition, administering MDSCs from both tumor- and nontumor-bearing mice can produce an acute-phase response. Thus, we propose a previously undescribed mechanism for the development of cancer cachexia, whereby progressive MDSC expansion contributes to changes in host protein and energy metabolism and reduced resistance to infection.
A tropical West Pacific OH minimum and implications for stratospheric composition
Authors: Rex M. , Wohltmann I. , Ridder T. , Lehmann R. , Rosenlof K. , Wennberg P. , Weisenstein D. , Notholt J. , Krüger K. , Mohr V. , Tegtmeier S.
Published: May 2014

Abstract. Most of the short-lived biogenic and anthropogenic chemical species that are emitted into the atmosphere break down efficiently by reaction with OH and do not reach the stratosphere. Here we show the existence of a pronounced minimum in the tropospheric column of ozone over the West Pacific, the main source region for stratospheric air, and suggest a corresponding minimum of the tropospheric column of OH. This has the potential to amplify the impact of surface emissions on the stratospheric composition compared to the impact when assuming globally uniform OH conditions. Specifically, the role of emissions of biogenic halogenated species for the stratospheric halogen budget and the role of increasing emissions of SO2 in Southeast Asia or from minor volcanic eruptions for the increasing stratospheric aerosol loading need to be reassessed in light of these findings. This is also important since climate change will further modify OH abundances and emissions of halogenated species. Our study is based on ozone sonde measurements carried out during the TransBrom cruise with the RV Sonne roughly along 140–150° E in October 2009 and corroborating ozone and OH measurements from satellites, aircraft campaigns and FTIR instruments. Model calculations with the GEOS-Chem Chemistry and Transport Model (CTM) and the ATLAS CTM are used to simulate the tropospheric OH distribution over the West Pacific and the transport pathways to the stratosphere. The potential effect of the OH minimum on species transported into the stratosphere is shown via modeling the transport and chemistry of CH2Br2 and SO2.