bluuebunny/crossref_metadata_2025 huggingface dataset:
Existence of positive solutions for second-order impulsive time scale boundary value problems on infinite intervals
Authors: Yaslan Ismail , Haznedar Zehra
Published: April 2015

In this paper, we consider nonlinear second order m-point impulsive time
scale boundary value problems on infinite intervals. By using Leray-Schauder
fixed point theorem, Avery-Henderson fixed point theorem and the five
functional fixed point theorem, respectively, we establish the criteria for
the existence of at least one, two and three positive solutions to the
nonlinear impulsive time scale boundary value problems on infinite intervals.
Approximation of viscosity zero points of accretive operators in a Banach space
Authors: Cho Sun , Kang Shin
Published: April 2015

In this paper, zero points of m-accretive operators are investigated based on
a viscosity iterative algorithm with double computational errors. Strong
convergence theorems for zero points of m-accretive operators are established
in a Banach space.
Degree distance of tensor product and strong product of graphs
Authors: Agnes Sheeba
Published: April 2015

In this paper, we determine the degree distance of G x Kr0,r1,...,rn-1 and G
? Kr0,r1,...,rn-1, where x and ? denote the tensor product and strong
product of graphs, respectively, and Kr0,r1,...,rn-1 denotes the
complete multipartite graph with partite sets V0,V1,...,Vn-1 where |Vj|
= rj, 0 ? j ? n - 1 and n ? 3. Using the formulae obtained here, we have
obtained the exact value of the degree distance of some classes of graphs.
Topological indices of the bipartite Kneser graph Hn,k
Authors: Mohammadyari R. , Darafsheh M.R.
Published: April 2015

In this paper we use transitivity property of the automorphism group of the
bipartite Kneser graph to calculate its Wiener, Szeged and PI indices.
Mixed-type reverse order law for Moore-Penrose inverse of products of three elements in ring with involution
Authors: Wang Long , Zhang Shuang , Zhang Xiao , Chen Jian
Published: April 2015

In this paper we establish some results concerning the mixed-type reverse
order laws for the Moore-Penrose inverse of various products of three
elements in rings with involution.
On almost ω1-n-simply presented Abelian p-groups
Authors: Danchev Peter
Published: April 2015

We define and investigate the class of almost ?1-n-simply presented p-torsion
abelian groups, which class properly contains the subclasses of almost
n-simply presented groups and ?1-n-simply presented groups, respectively.
The obtained results generalize those obtained by us in Korean J. Math.
(2014) and J. Algebra Appl. (2015).
Fixed points for Ciric-G-contractions in uniform spaces endowed with a graph
Authors: Aghanians Aris , Fallahi Kamal , Nourouzi Kourosh , Verma Ram
Published: April 2015

We investigate the notion of ?-generalized contractions introduced by Ciric
in uniform spaces endowed with a graph and discuss on the existence and
uniqueness of fixed points for this type of contractions using the basic
entourages.
Commutators on l2-spaces
Authors: Kapustin Vladimir
Published: April 2015

Given a normal operator N on a Hilbert space and an operator X for which the
commutator K = XN ?NX belongs to the Hilbert-Schmidt class, we discuss the
possibility to represent X as a sum of a Cauchy transform corresponding to K
in the spectral representation of N and an operator commuting with N.
Asimptoticeskoe razlozenie dlja resenija neodnorodnogo raznostnogo uravnenija obscego vida
Authors: Sgibnev M.S.
Published: April 2015

We obtain an asymptotic expansion for the solution of a nonhomogeneous
difference equation of general type. The influence of the roots of the
characteristic equation is taken into a count. An integral estimate with
submultiplicative weight function is established for the remainder term
depending on the existence of a corresponding submultiplicative moment of
the free term of the equation.
Groups with finitely many countable models
Authors: Ilic Dejan , Moconja Slavko , Tanovic Predrag
Published: April 2015

We construct Abelian group with an extra structure whose first order theory
has finitely many but more than one countable model.
Enumeration of certain classes of antichains
Authors: Kilibarda Goran
Published: April 2015

An antichain is here regarded as a hypergraph that satisfies the following
property: neither of every two different edges is a subset of the other one.
The paper is devoted to the enumeration of antichains given on an n-set and
having one or more of the following properties: being labeled or unlabeled;
being ordered or unordered; being a cover (or a proper cover); and finally,
being a T0-, T1- or T2-hypergraph. The problem of enumeration of these
classes comprises, in fact, different modifications of Dedekind?s problem.
Here a theorem is proved, with the help of which a greater part of these
classes can be enumerated. The use of the formula from the theorem is
illustrated by enumeration of labeled antichains, labeled T0-antichains,
ordered unlabeled antichains, and ordered unlabeled T0-antichains. Also a
list of classes that can be enumerated in a similar way is given. Finally, we
perform some concrete counting, and give a table of digraphs that we used in
the counting process.
On sturdy frame of abstract algebras
Authors: Shao Yong , Ren Miaomiao
Published: April 2015

We introduce the notion of a sturdy frame of abstract algebras which is a
common generalization of a sturdy semilattice of semigroups, the sum of
lattice ordered systems, the strong distributive lattice of semirings, the
sturdy frame of type (2, 2) algebras and the strong b-lattice of semirings.
Also, we give some properties and characterizations of the sturdy frame of
abstract algebras. As an application, we study the sturdy distributive
lattice of lattice ordered groups.
Irrationality measures for continued fractions with arithmetic functions
Authors: Hancl Jaroslav , Leppälä Kalle
Published: April 2015

Let f(n) or the base-2 logarithm of f(n) be either d(n) (the divisor
function), ?(n) (the divisor-sum function), ?(n) (the Euler totient
function), ?(n) (the number of distinct prime factors of n) or ?(n) (the
total number of prime factors of n). We present good lower bounds for |M/N
? ?| in terms of N, where ? = [0; f(1), f(2),...].
Bass numbers of generalized local cohomology modules
Authors: Payrovi Sh. , Babaei S. , Khalili-Gorji I.
Published: April 2015

Let R be a Noetherian ring, M a finitely generated R-module and N an
arbitrary R-module. We consider the generalized local cohomology modules,
with respect to an arbitrary ideal I of R, and prove that, for all
nonnegative integers r, t and all p ? Spec(R) the Bass number ?r(p,HtI
(M,N)) is bounded above by ?tj=0?r(p, t?jExtR (M,HjI (N))). A corollary
is that Ass (HtI (M,N)? Utj=0 Ass (t?jExtR (M,HjI(N))). In a
slightly different direction, we also present some well known results about
generalized local cohomology modules.
On the convergence of a class of the regularization methods for ill-posed quadratic minimization problems with constraint
Authors: Jacimovic Milojica , Krnic Izedin , Obradovic Oleg
Published: April 2015

We study a class of regularization methods for solving least-squares
ill-posed problem with a convex constraint. Convergence and convergence rate
results are proven for the problems which satisfy so called power source
condition. All the results are obtained under the assumptions that, instead
of exact initial data, only their approximations are known.
Segal’s multisimplicial spaces
Authors: Petric Zoran
Published: April 2015

Some sufficient conditions on a simplicial space X : ?op ? Top guaranteeing
that X1 ? ?|X| were given by Segal. We give a generalization of this result
for multisimplicial spaces. This generalization is appropriate for the
reduced bar construction, providing an n-fold delooping of the classifying
space of a category.
Hopf algebra of projection functions
Authors: Mijajlovic Zarko , Pejovic Aleksandar
Published: April 2015

We study Hopf algebras over projection functions of the complex vector CX
appropriate for computing inversion formulas from discrete mathematics. Using
calculus of projection functions introduced in this way, we derived various
inversion formulas, including Gould?s inversion formula and its
generalizations.
On linear combinations of Chebyshev polynomials
Authors: Stankov Dragan
Published: April 2015

We investigate an infinite sequence of polynomials of the form: a0Tn(x) +
a1Tn?1(x) + ... + amTn?m(x) where (a0, a1,..., am) is a fixed m-tuple
of real numbers, a0, am ? 0, Ti(x) are Chebyshev polynomials of the first
kind, n = m, m+ 1, m+ 2,.... Here we analyze the structure of the set of
zeros of such polynomial, depending on A and its limit points when n tends
to infinity. Also the expression of envelope of the polynomial is given. An
application in number theory, more precise, in the theory of Pisot and Salem
numbers, is presented.
Effects of the thickness on the microstructure and corrosion behavior of a TiAlN film on 4140 steel
Authors: Wongpanya Pornwasa , Wongpinij Thipusa , Photongkam Pat , Euaruksakul Chanan , Witit-anun Nirun
Published: April 2015

TiAlN films with thicknesses of 250, 500 and 750 nm were deposited on 4140 steel using the reactive direct current co-unbalanced magnetron sputtering method. The effects of the film thickness on the microstructure were revealed using a field emission scanning electron microscope, an image analyzer and X-ray diffraction. The results showed that grain size apparently increased when the film was at greater thicknesses whereas porosity, lattice strain and dislocation density decreased. Meanwhile, the results of anodic polarization tests in air-saturated 3.5 wt.-% NaCl solution at pH levels of 2, 7 and 10 and at 25 °C showed lower corrosion potential in thicker film, attributed to a lower ratio of grain boundary area to individual grain area. However, a more stable passive film with higher pitting potential was formed. By analyzing using X-ray absorption spectromicroscopy, oxidation of Ti into TiO2 was found on the corroded surface of TiAlN film.
Corrosion resistance of nanosilicasilicate conversion coatings on aluminum prepared by the dip immersion method
Authors: Bahri Hamed , Danaee Iman , Rashed Gholam Reza
Published: April 2015

Nanosilica modified potassium silicate conversion coatings were deposited on the surface of 2024 aluminum alloy by the dip immersion method, and the effect of the immersion time was studied on anticorrosion behavior of coatings. The corrosion behavior of coatings was examined by means of electrochemical impedance spectroscopy, potentiodynamic polarization and surface analyzing techniques. The coated samples showed a significant decrease in corrosion rate. The experimental results indicated that the increase in silica ratio led to an increasing in the corrosion resistance of aluminum. Immersion time in potassium silicate solution showed a significant effect on silicate conversion coating and higher corrosion resistance was obtained with 400 s immersion. This behavior can be related to increasing the silicate coating continuity which formed on the surface. The coating performance evaluated in acidic and basic NaCl solution as well as the results showed the corresponding stability of nanosilica modified silicate conversion coating in these solutions.
Investigation of joints between polypropylene and polybutylene terephthalate
Authors: Bekem Aylin , Unal Ahmet
Published: April 2015

An effective joining between polypropylene (PP) and polybutylene terephthalate (PBT) is closely related to bonding between PP and PBT. The objective of this study is to improve the bonding between PBT and PP with a compatibilizer application between joints as tie-layer at various concentrations. Flexural strength, lap-shear strength and interlaminar shear strength of joined parts were determined to determine the adhesive bonding performance. The fracture behavior of the bonds was also investigated. It was found that using compatibilizers in a PP/PBT joining system improved the mechanical characteristics. Improved results were obtained with increasing ratios of compatibilizers in tie-layer and maximum mechanical results were achieved for 100 % compatibilizer usage in PP-PBT system.
Parametric optimization of seam welding of stainless steel (SS 304) sheets
Authors: Krishnan Muthuraman Pandi , Sait Abdullah Naveen , Ravichandran Manickam
Published: April 2015

In the present study, seam welding process parameters were optimized for joining 306 stainless steel plates. Welding pressure, welding speed and welding temperature combinations were carefully selected with the objective of producing a weld joint with maximum impact strength and hardness. Taguchi technique was applied for optimizing the selected welding parameters. The factors used in this study consisted of pressure, welding speed and welding temperature, each of which had three levels in the study. L27 orthogonal array and corresponding levels were selected according to the aforementioned factors and experimental tests were performed. Signal-to-noise (S/N) ratio was used to evaluate the experimental results. The results indicate that the welding speed has the greatest influence on impact strength, followed by welding pressure and temperature. Experiments have also been conducted to validate the optimized parameters.
Diffusion characteristics of plasma nitrided hard chromium on AISI 1010 steel
Authors: Danışman Murat , Kocabaş Mustafa , Cansever Nurhan
Published: April 2015

In order to investigate the different Cr-N formation characteristics of plasma nitrided hard Cr coatings, Cr was electrodeposited on AISI 1010 steel and plasma nitrided at 600, 700 and 800 °C for 3 h, 5 h and 7 h, respectively. Phase analyses of resulting Cr-N phases and grain size of Cr layer before and after nitriding process were calculated by X-ray diffraction analysis. Structure of nitride layer and its thickness were analyzed using scanning electron microscopy micrographs. The micrographs indicated that samples consisted of three distinctive layers. In order to distinguish these layers, scanning electron microscopy and energy dispersive spectroscopy (EDX) analysis were used as well as elemental distribution versus depth was plotted. The Cr-N diffusion was investigated by layer thickness measurements, and diffusion coefficient as well as activation energies were calculated.
Benefits of Precision Farming Technologies for Mechanical Weed Control in Soybean and Sugar Beet—Comparison of Precision Hoeing with Conventional Mechanical Weed Control
Authors: Kunz Christoph , Weber Jonas , Gerhards Roland
Published: April 2015

Weed infestations and associated yield losses require effective weed control measures in soybean and sugar beet. Besides chemical weed control, mechanical weeding plays an important role in integrated weed management systems. Field experiments were conducted at three locations for soybean in 2013 and 2014 and at four locations for sugar beet in 2014 to investigate if automatic steering technologies for inter-row weed hoeing using a camera or RTK-GNSS increase weed control efficacy, efficiency and crop yield. Treatments using precision farming technologies were compared with conventional weed control strategies. Weed densities in the experiments ranged from 15 to 154 plants m−2 with Chenopodium album, Polygonum convolvulus, Polygonum aviculare, Matricaria chamomilla and Lamium purpureum being the most abundant species. Weed hoeing using automatic steering technologies reduced weed densities in soybean by 89% and in sugar beet by 87% compared to 85% weed control efficacy in soybean and sugar beet with conventional weeding systems. Speed of weed hoeing could be increased from 4 km h−1 with conventional hoes to 7 and 10 km·h−1, when automatic steering systems were used. Precision hoeing technologies increased soybean yield by 23% and sugar beet yield by 37%. After conventional hoeing and harrowing, soybean yields were increased by 28% and sugar beet yield by 26%.
A Novel Point-of-Care Biomarker Recognition Method: Validation by Detecting Marker for Diabetic Nephropathy
Authors: Pentyala Sahana , Muller John , Tumillo Thomas , Roy Avijit , Mysore Pooja , Pentyala Srinivas
Published: April 2015

Biological fluid collection to identify and analyze different disease markers is a routine and normal procedure in health care settings. Body fluids are as varied as urine, blood, mucus, cerebrospinal fluid (CSF), tears, semen, etc. The volumes of the collected fluids range from micro liters (e.g., tears, CSF) to tens and hundreds of milliliters (blood, urine, etc.). In some manifestations, a disease marker (particularly protein markers) can occur in trace amounts, yet the fluids collected are in large volumes. To identify these trace markers, cumbersome methods, expensive instruments, and trained personnel are required. We developed an easy method to rapidly capture, concentrate, and identify protein markers in large volumes of test fluids. This method involves the utilization of two antibodies recognizing two different epitopes of the protein biomarker. Antibody-1 helps to capture and concentrate the biomarker and Antibody-2 adsorbed or conjugated to nanogold beads will detect the biomarker. This method was validated in capturing and detecting lipocalin type prostaglandin-D2 synthase, a marker in urine that implicates diabetic nephropathy. A one-step collection, concentration, and detection device was designed based on this method. This device can replace many of the normal body fluid collection devices such as tubes and containers. A one-step fluid collection and biomarker capture and concentration device for rapid diagnosis of diseases has tremendous advantage in terms of cost and providing timely results.
Randomized Clinical Investigation of Titanium Implants with and without Platform Switching: Six Months’ Radiographic and Clinical Outcome
Authors: Rossi Roberto , Capri Diego , Risciotti Emanuele , Zeman Paul
Published: April 2015

The aim of this study was to obtain a randomized, clinical and radiological comparison of implants with and without platform switching (PFS). The two compared titanium implant types differed only in the microgap position: test (PFS) or control (StE, no PFS). All implants were inserted in posterior regions and followed up for six months after abutment connection (AC). Twenty one patients with 21 PFS and 18 StE implants completed the six-month evaluation. No implant failed. One complication (exposed cap screw) was reported at AC. No statistically significant difference was observed between the marginal bone level of PFS and StE implants. Their bone level stabilized approximately 1 mm below the microgap. Based on the outcome of this short-term study with a limited number of patients, it seems unlikely that the optimal clinical and radiological outcome obtained with the tested standard implant (no PFS) can be improved by introducing an inward microgap shift (PFS).
Fuzzy Controller for a Voltage-Regulated Solar-Powered MPPT System for Hybrid Power System Applications
Authors: Shiau Jaw-Kuen , Wei Yu-Chen , Lee Min-Yi
Published: April 2015

This paper presents the design of a fuzzy-logic-based voltage-regulated solar power maximum power point tracking (MPPT) system for applications involving hybrid power systems. The system contains a solar power system and battery as the primary and secondary power sources, respectively. The solar system alone supplies power to the electric motor and maintains the output voltage at a predetermined level when it has sufficient power. When the solar power is insufficient, the solar system is operated at its maximum power point (MPP) and the battery is engaged to compensate for the insufficiency. First, a variant of the incremental conductance MPP condition was established. Under the MPP condition, the voltage-regulated MPPT system was formulated as a feedback control system, where the MPP condition and voltage regulation requirements were used as the system inputs. Next, a fuzzy controller was developed to perform the voltage-regulated MPPT function for the hybrid power system. A simulation model based on Matrix laboratory (MATLAB)/SIMULINK (a block diagram environment for multi-domain simulation and model-based design) and a piecewise linear electric circuit simulation (PLECS) tool for controlling the dc motor velocity was developed to verify the voltage-regulated solar power MPPT system.
The Partnering with Patients Model of Nursing Interventions: A First Step to a Practice Theory
Authors: Moyle Wendy , Rickard Claire , Chambers Suzanne , Chaboyer Wendy
Published: April 2015

The development of a body of knowledge, gained through research and theory building, is one hallmark of a profession. This paper presents the “Partnering with Patients Model of Nursing Interventions”, providing direction towards how complex nursing interventions can be developed, tested and subsequently adopted into practice. Coalescence of understanding of patient-centred care, the capabilities approach and the concept of complex healthcare interventions led to the development of the model assumptions and concepts. Application of the model to clinical practice is described, including presentation of a case study, and areas for future research including understanding both patients’ and nurses’ perceptions and experiences when the model is in use, and testing the effect of nursing interventions based on the model are recommended.
Hydrological Model Calibration by Sequential Replacement of Weak Parameter Sets Using Depth Function
Authors: Singh Shailesh , Bárdossy András
Published: April 2015

It is always a dream of hydrologists to model the mystery of complex hydrological processes in a precise way. If parameterized correctly, a simple hydrological model can represent nature very accurately. In this study, a simple and effective optimization algorithm, sequential replacement of weak parameters (SRWP), is introduced for automatic calibration of hydrological models. In the SRWP algorithm, a weak parameter set is sequentially replaced with another deeper and good parameter set. The SRWP algorithm is tested on several theoretical test functions, as well as with a hydrological model. The SRWP algorithm result is compared with the shuffled complex evolution-University of Arizona (SCE-UA) algorithm and the robust parameter estimation (ROPE) algorithm. The result shows that the SRWP algorithm easily overcomes the local minima and converges to the optimal parameter space. The SRWP algorithm does not converge to a single optima; instead, it gives a convex hull of an optimal space. An ensemble of results can be generated from the optimal space for prediction purpose. The ensemble spread will account for the parameter estimation uncertainty. The methodology was demonstrated using the hydrological model (HYMOD) conceptual model on upper Neckar catchments of southwest Germany. The results show that the parameters estimated by this stepwise calibration are robust and comparable to commonly-used optimization algorithms. SRWP can be an alternative to other optimization algorithms for model calibration.
Drug Use and HIV Infection Status of Detainees in Re-Education through Labour Camps in Guangxi Province, China
Authors: Zhang Lei , Yap Lorraine , Reekie Joanne , Liu Wei , Chen Yi , Wu Zunyou , Wand Handan , Butler Tony
Published: April 2015

This study describes HIV disease burden and patterns of drug use before and during incarceration among detainees in Re-education-Through-Labour-Camps (RTLCs) in China. A cross-sectional survey of 576 men and 179 women from three RTLCs was conducted in Guangxi Province, China. Over three-quarters of study participants were detained due to drug-related offences. Over half of the women (n = 313, 54.3%) and two-thirds of men (n = 119, 66.5%) had been previously been incarcerated in a compulsory detoxification treatment centre (CDTC), and around one-third (men n = 159, 27.6%; women n = 50, 27.9%) in a RTLC. Of those surveyed, 49 men (8.5%) and one (0.6%) woman reported ever using drugs while in a CDTC and/or RTLC. Previous incarceration in CDTCs and RTLCs were associated with HIV infection among both male (OR = 2.15 [1.11–4.15]) and female (OR = 3.87 [1.86–9.04]) detainees. Being married/cohabiting with a partner (OR = 0.53, [0.30–0.93]) and being employed (OR = 0.46, [0.22–0.95]) were associated with a reduced odds of HIV infection among male detainees. A significant proportion of RTLC detainees had a history of drug use and a limited number of inmates had used illegal substances whilst in custody. Repeat incarcerations in CDTCs/RTLCs were associated with higher risks of HIV infection.
Remotely Sensed Soil Data Analysis Using Artificial Neural Networks: A Case Study of El-Fayoum Depression, Egypt
Authors: Amato Filippo , Havel Josef , Gad Abd-Alla , El-Zeiny Ahmed
Published: April 2015

Earth observation and monitoring of soil quality, long term changes of soil characteristics and deterioration processes such as degradation or desertification are among the most important objectives of remote sensing. The georeferenciation of such information contributes to the development and progress of the Digital Earth project in the framework of the information globalization process. Earth observation and soil quality monitoring via remote sensing are mostly based on the use of satellite spectral data. Advanced techniques are available to predict the soil or land use/cover categories from satellite imagery data. Artificial Neural Networks (ANNs) are among the most widely used tools for modeling and prediction purposes in various fields of science. The assessment of satellite image quality and suitability for analysing the soil conditions (e.g., soil classification, land use/cover estimation, etc.) is fundamental. In this paper, methodology for data screening and subsequent application of ANNs in remote sensing is presented. The first stage is achieved via: (i) elimination of outliers, (ii) data pre-processing and (iii) the determination of the number of distinguishable soil “classes” via Eigenvalues Analysis (EA) and Principal Components Analysis (PCA). The next stage of ANNs use consists of: (i) building the training database, (ii) optimization of ANN architecture and database cleaning, and (iii) training and verification of the network. Application of the proposed methodology is shown.
Overexpressing of OsAMT1-3, a High Affinity Ammonium Transporter Gene, Modifies Rice Growth and Carbon-Nitrogen Metabolic Status
Authors: Bao Aili , Liang Zhijun , Zhao Zhuqing , Cai Hongmei
Published: April 2015

AMT1-3 encodes the high affinity NH4+ transporter in rice roots and is predominantly expressed under nitrogen starvation. In order to evaluate the effect of AMT1-3 gene on rice growth, nitrogen absorption and metabolism, we generated AMT1-3-overexpressing plants and analyzed the growth phenotype, yield, carbon and nitrogen metabolic status, and gene expression profiles. Although AMT1-3 mRNA accumulated in transgenic plants, these plants displayed significant decreases in growth when compared to the wild-type plants. The nitrogen uptake assay using a 15N tracer revealed poor nitrogen uptake ability in AMT1-3-overexpressing plants. We found significant decreases in AMT1-3-overexpressing plant leaf carbon and nitrogen content accompanied with a higher leaf C/N ratio. Significant changes in soluble proteins and carbohydrates were also observed in AMT1-3-overexpressing plants. In addition, metabolite profile analysis demonstrated significant changes in individual sugars, organic acids and free amino acids. Gene expression analysis revealed distinct expression patterns of genes that participate in carbon and nitrogen metabolism. Additionally, the correlation between the metabolites and gene expression patterns was consistent in AMT1-3-overexpressing plants under both low and high nitrogen growth conditions. Therefore, we hypothesized that the carbon and nitrogen metabolic imbalance caused by AMT1-3 overexpressing attributed to the poor growth and yield of transgenic plants.
Further Study on Chemical Constituents of Parnassia wightiana Wall: Four New Dihydro-β-agarofuran Sesquiterpene Polyesters
Authors: Gao Zhao-Feng , Zhou Bo-Hang , Zhao Jie-Yu , Cao Fang-Jun , Zhou Le , Geng Hui-Ling
Published: April 2015

Four new (1–4), along with six known (5–10) dihydro-β-agarofuran sesquiterpene polyesters were isolated from the whole plants of Parnassia wightiana. The new compounds were structurally elucidated through spectroscopic analysis including UV (Ultraviolet Spectrum), IR (Infrared Spectrum), 1H-NMR (1Hydrogen-Nuclear Magnetic Resonance), 13C-NMR (13Carbon-Nuclear Magnetic Resonance), DEPT (Distortionless Enhancement by Polarization Transfer), 1H-1H COSY (1H-1H Correlation Spectroscopy), HSQC (Heteronuclear Single Quantum Coherence), HMBC (Heteronuclear Multiple Bond Correlation), NOESY (Nuclear Overhauser Enhancement Spectroscopy) and HR-MS (High Resolution Mass Specttrum) and their absolute configurations were proposed by comparison of NOESY spectra and specific optical rotations with those of known compounds and biosynthesis grounds. Compound 2 is the first sesquiterpene alkaloid isolated from this plant. New compounds 1–4 exhibited some cytotoxic activities against NB4, MKN-45 and MCF-7 cells at 20 μM and of which 4 showed the highest activity against NB4 and MKN-45 cells with inhibition rates of 85.6% and 30.5%, respectively.
Expression Profiling Reveals Genes Involved in the Regulation of Wool Follicle Bulb Regression and Regeneration in Sheep
Authors: Liu Guangbin , Liu Ruize , Tang Xiaohui , Cao Jianhua , Zhao Shuhong , Yu Mei
Published: April 2015

Wool is an important material in textile manufacturing. In order to investigate the intrinsic factors that regulate wool follicle cycling and wool fiber properties, Illumina sequencing was performed on wool follicle bulb samples from the middle anagen, catagen and late telogen/early anagen phases. In total, 13,898 genes were identified. KRTs and KRTAPs are the most highly expressed gene families in wool follicle bulb. In addition, 438 and 203 genes were identified to be differentially expressed in wool follicle bulb samples from the middle anagen phase compared to the catagen phase and the samples from the catagen phase compared to the late telogen/early anagen phase, respectively. Finally, our data revealed that two groups of genes presenting distinct expression patterns during the phase transformation may have important roles for wool follicle bulb regression and regeneration. In conclusion, our results demonstrated the gene expression patterns in the wool follicle bulb and add new data towards an understanding of the mechanisms involved in wool fiber growth in sheep.
Proteomic Insights into Sulfur Metabolism in the Hydrogen-Producing Hyperthermophilic Archaeon Thermococcus onnurineus NA1
Authors: Moon Yoon-Jung , Kwon Joseph , Yun Sung-Ho , Lim Hye , Kim Jonghyun , Kim Soo , Kang Sung , Lee Jung-Hyun , Kim Seung , Chung Young-Ho
Published: April 2015

The hyperthermophilic archaeon Thermococcus onnurineus NA1 has been shown to produce H2 when using CO, formate, or starch as a growth substrate. This strain can also utilize elemental sulfur as a terminal electron acceptor for heterotrophic growth. To gain insight into sulfur metabolism, the proteome of T. onnurineus NA1 cells grown under sulfur culture conditions was quantified and compared with those grown under H2-evolving substrate culture conditions. Using label-free nano-UPLC-MSE-based comparative proteomic analysis, approximately 38.4% of the total identified proteome (589 proteins) was found to be significantly up-regulated (≥1.5-fold) under sulfur culture conditions. Many of these proteins were functionally associated with carbon fixation, Fe–S cluster biogenesis, ATP synthesis, sulfur reduction, protein glycosylation, protein translocation, and formate oxidation. Based on the abundances of the identified proteins in this and other genomic studies, the pathways associated with reductive sulfur metabolism, H2-metabolism, and oxidative stress defense were proposed. The results also revealed markedly lower expression levels of enzymes involved in the sulfur assimilation pathway, as well as cysteine desulfurase, under sulfur culture condition. The present results provide the first global atlas of proteome changes triggered by sulfur, and may facilitate an understanding of how hyperthermophilic archaea adapt to sulfur-rich, extreme environments.
Biochemical Synthesis of Ag/AgCl Nanoparticles for Visible-Light-Driven Photocatalytic Removal of Colored Dyes
Authors: Zhao Xiyun , Zhang Jie , Wang Binsong , Zada Amir , Humayun Muhammad
Published: April 2015

Photocatalytic removal of organic pollution such as waste colored dyes was a promising technique for environment technique. However, effective photocatalysts were needed to enhance the photocatalytic efficiency. Ag/AgCl was regarded as high performance catalyst for photocatalytic degradation. Ag/AgCl nanoparticles were biochemically prepared with metabolin of living fungi which was used as reductant and characterized by X-Ray diffraction (XRD), UV-visible spectroscopy and transmission electron microscopy (TEM). The Ag/AgCl nanoparticle composites showed spherical aggregation shape with an average size of about 3–5 nm which is well inside the quantum regime. The UV-visible study showed that Ag/AgCl nanoparticles had strong visible light absorption and exhibited excellent visible-light-driven photocatalytic performance. Photocatalytic results indicated that the obtained Ag/AgCl nanoparticles were suitable for photocatalytic removal of RhB dye under visible light irradiation. The excellent photocatalytic activities could be attributed to the quantum size nanoparticles and the Plasmon resonance of Ag/AgCl composites.
Fabrication of Diamond Based Sensors for Use in Extreme Environments
Authors: Samudrala Gopi , Moore Samuel , Vohra Yogesh
Published: April 2015

Electrical and magnetic sensors can be lithographically fabricated on top of diamond substrates and encapsulated in a protective layer of chemical vapor deposited single crystalline diamond. This process when carried out on single crystal diamond anvils employed in high pressure research is termed as designer diamond anvil fabrication. These designer diamond anvils allow researchers to study electrical and magnetic properties of materials under extreme conditions without any possibility of damaging the sensing elements. We describe a novel method for the fabrication of designer diamond anvils with the use of maskless lithography and chemical vapor deposition in this paper. This method can be utilized to produce diamond based sensors which can function in extreme environments of high pressures, high and low temperatures, corrosive and high radiation conditions. We demonstrate applicability of these diamonds under extreme environments by performing electrical resistance measurements during superconducting transition in rare earth doped iron-based compounds under high pressures to 12 GPa and low temperatures to 10 K.
Effect of Layer and Film Thickness and Temperature on the Mechanical Property of Micro- and Nano-Layered PC/PMMA Films Subjected to Thermal Aging
Authors: Abdel-Mohti Ahmed , Garbash Alison , Almagahwi Saad , Shen Hui
Published: April 2015

Multilayered polymer films with biomimicking, layered structures have unique microstructures and many potential applications. However, a major limitation of polymer films is the deterioration of mechanical properties in working environments. To facilitate the design and development of multilayered polymer films, the impact of thermal aging on the mechanical behavior of micro- and nano-layered polymer films has been investigated experimentally. The composition of the polymer films that have been studied is 50 vol% polycarbonate (PC) and 50 vol% poly(methyl methacrylate) (PMMA). The current study focuses on the effect of film and layer thickness and temperature on the mechanical properties of the materials subjected to thermal aging. To study the effect of film and layer thickness, films with the same thickness, but various layer thicknesses, and films with the same layer thickness, but various film thicknesses, were thermally aged at 100 °C in a constant temperature oven for up to six weeks. The results show that as the layer thickness decreases to 31 nm, the film has a higher stiffness and strength, and the trend of the mechanical properties is relatively stable over aging. The ductility of all of the films decreases with aging time. To study the effect of temperature, the films with 4,096 layers (31 nm thick for each layer) were aged at 100 °C, 115 °C and 125 °C for up to four weeks. While the 100 °C aging results in a slight increase of the stiffness and strength of the films, the higher aging temperature caused a decrease of the stiffness and strength of the films. The ductility decreases with the aging time for all of the temperatures. The films become more brittle for higher aging temperatures.
Inhibition of Oncogenic Transcription Factor REL by the Natural Product Derivative Calafianin Monomer 101 Induces Proliferation Arrest and Apoptosis in Human B-Lymphoma Cell Lines
Authors: Yeo Alan , Chennamadhavuni Spandan , Whitty Adrian , Porco John , Gilmore Thomas
Published: April 2015

Increased activity of transcription factor NF-κB has been implicated in many B-cell lymphomas. We investigated effects of synthetic compound calafianin monomer (CM101) on biochemical and biological properties of NF-κB. In human 293 cells, CM101 selectively inhibited DNA binding by overexpressed NF-κB subunits REL (human c-Rel) and p65 as compared to NF-κB p50, and inhibition of REL and p65 DNA binding by CM101 required a conserved cysteine residue. CM101 also inhibited DNA binding by REL in human B-lymphoma cell lines, and the sensitivity of several B-lymphoma cell lines to CM101-induced proliferation arrest and apoptosis correlated with levels of cellular and nuclear REL. CM101 treatment induced both phosphorylation and decreased expression of anti-apoptotic protein Bcl-XL, a REL target gene product, in sensitive B-lymphoma cell lines. Ectopic expression of Bcl-XL protected SUDHL-2 B-lymphoma cells against CM101-induced apoptosis, and overexpression of a transforming mutant of REL decreased the sensitivity of BJAB B-lymphoma cells to CM101-induced apoptosis. Lipopolysaccharide-induced activation of NF-κB signaling upstream components occurred in RAW264.7 macrophages at CM101 concentrations that blocked NF-κB DNA binding. Direct inhibitors of REL may be useful for treating B-cell lymphomas in which REL is active, and may inhibit B-lymphoma cell growth at doses that do not affect some immune-related responses in normal cells.
Synthesis and 11C-Radiolabelling of 2-Carboranyl Benzothiazoles
Authors: Gona Kiran , Thota Jaya , Baz Zuriñe , Gómez-Vallejo Vanessa , Llop Jordi
Published: April 2015

Dicarba-closo-dodecaboranes, commonly known as carboranes, possess unique physico-chemical properties and can be used as hydrophobic moieties during the design of new drugs or radiotracers. In this work, we report the synthesis of two analogues of 2-(4-aminophenyl)benzothiazole (a compound that was found to elicit pronounced inhibitory effects against certain breast cancer cell lines in vitro) in which the phenyl ring has been substituted by a m-carborane cage. Two different synthetic strategies have been used. For the preparation of 1-(9-amino-1,7-dicarba-closo-dodecaboran-1-yl)-benzo-thiazole, the benzothiazole group was first introduced on one of the cluster carbon atoms of m-carborane and the amine group was further attached in three steps. For the synthesis of 1-(9-amino-1,7-dicarba-closo-dodecaboran-1-yl)-6-hydroxybenzothiazole, iodination was performed before introducing the benzothiazole group, and the amino group was subsequently introduced in six steps. Both compounds were radiolabelled with carbon-11 using [11C]CH3OTf as the labelling agent. Radiolabelling yields and radiochemical purities achieved should enable subsequent in vitro and in vivo investigations.
A Bayesian Approach to Combine Landsat and ALOS PALSAR Time Series for Near Real-Time Deforestation Detection
Authors: Reiche Johannes , De Bruin Sytze , Hoekman Dirk , Verbesselt Jan , Herold Martin
Published: April 2015

To address the need for timely information on newly deforested areas at medium resolution scale, we introduce a Bayesian approach to combine SAR and optical time series for near real-time deforestation detection. Once a new image of either of the input time series is available, the conditional probability of deforestation is computed using Bayesian updating, and deforestation events are indicated. Future observations are used to update the conditional probability of deforestation and, thus, to confirm or reject an indicated deforestation event. A proof of concept was demonstrated using Landsat NDVI and ALOS PALSAR time series acquired at an evergreen forest plantation in Fiji. We emulated a near real-time scenario and assessed the deforestation detection accuracies using three-monthly reference data covering the entire study site. Spatial and temporal accuracies for the fused Landsat-PALSAR case (overall accuracy = 87.4%; mean time lag of detected deforestation = 1.3 months) were consistently higher than those of the Landsat- and PALSAR-only cases. The improvement maintained even for increasing missing data in the Landsat time series.
The Effect of Topography on Target Decomposition of Polarimetric SAR Data
Authors: Park Sang-Eun
Published: April 2015

Polarimetric target decomposition enables the interpretation of radar images more easily, mostly based on physical assumptions, i.e., fitting physically-based scattering models to the polarimetric SAR observations. However, the model-fitting result cannot be always successful. Particularly, the performance of model-fitting in sloping forests is still an open question. In this study, the effect of ground topography on the model-fitting-based polarimetric decomposition techniques is investigated. The estimation accuracy of each scattering component in the decomposition results are evaluated based on the simulated target matrix by using the incoherent vegetation scattering model that accounts for the tilted scattering surface beneath the forest canopy. Experimental results show that the surface and the double-bounce scattering components can be significantly misestimated due to the topographic slope, even when the volume scattering power is successfully estimated.
Use of LUCAS LC Point Database for Validating Country-Scale Land Cover Maps
Authors: Karydas Christos , Gitas Ioannis , Kuntz Steffen , Minakou Chara
Published: April 2015

In this study, the Land Use/Cover Area frame statistical Survey (LUCAS) of 2009 was used as a reference dataset for validating a Land Cover Map of Greece for 2007, produced with remote sensing by the Greek Office of the World Wildlife Fund (WWF Hellas). First, all class definitions were decomposed in terms of four vegetation parameters (type, height, density, and composition), considered as critical in indicating unconformities between LUCAS and the WWF Hellas map; their inter-class relations were described in a table of correspondence. Then, a two-tier methodology was applied: an “automated” process, where thematic agreement was based exclusively on the main land cover attribute of LUCAS (LC1); and a “supervised” process, where thematic agreement was based on the reinterpretation of LUCAS ground photos and use of ancillary earth observation imagery; non-square error matrix was deployed in both processes. For the supervised process specifically, a decision-tree was designed, using the critical vegetation parameters (mentioned above) as quantified criteria, thus allowing objective labelling of testing points in both systems. The results show that only a small proportion of the reassessed points verified the WWF Hellas map predictions and that the overall accuracy of the supervised process was reduced compared to that of the automated process. In conclusion, the LUCAS point database was found to be supportive, but not fully efficient, for identifying the various sources of error in country-scale land cover maps derived with remote sensing. Synergy with very high resolution satellite images and air photos, or a dedicated ground truth campaign, seems to be inevitable in order to validate their thematic accuracy, especially in highly heterogeneous environments. In this direction, LUCAS could be used as a verification, rather than a validation, dataset.
Mapping Above-Ground Biomass in a Tropical Forest in Cambodia Using Canopy Textures Derived from Google Earth
Authors: Singh Minerva , Evans Damian , Friess Daniel , Tan Boun , Nin Chan
Published: April 2015

This study develops a modelling framework for utilizing very high-resolution (VHR) aerial imagery for monitoring stocks of above-ground biomass (AGB) in a tropical forest in Southeast Asia. Three different texture-based methods (grey level co-occurrence metric (GLCM), Gabor wavelets and Fourier-based textural ordination (FOTO)) were used in conjunction with two different machine learning (ML)-based regression techniques (support vector regression (SVR) and random forest (RF) regression). These methods were implemented on both 50-cm resolution Digital Globe data extracted from Google Earth™ (GE) and 8-cm commercially obtained VHR imagery. This study further examines the role of forest biophysical parameters, such as ground-measured canopy cover and vertical canopy height, in explaining AGB distribution. Three models were developed using: (i) horizontal canopy variables (i.e., canopy cover and texture variables) plus vertical canopy height; (ii) horizontal variables only; and (iii) texture variables only. AGB was variable across the site, ranging from 51.02 Mg/ha to 356.34 Mg/ha. GE-based AGB estimates were comparable to those derived from commercial aerial imagery. The findings demonstrate that novel use of this array of texture-based techniques with GE imagery can help promote the wider use of freely available imagery for low-cost, fine-resolution monitoring of forests parameters at the landscape scale.
Lower Extremity Joint Angle Tracking with Wireless Ultrasonic Sensors during a Squat Exercise
Authors: Qi Yongbin , Soh Cheong , Gunawan Erry , Low Kay-Soon , Thomas Rijil
Published: April 2015

This paper presents an unrestrained measurement system based on a wearable wireless ultrasonic sensor network to track the lower extremity joint and trunk kinematics during a squat exercise with only one ultrasonic sensor attached to the trunk. The system consists of an ultrasound transmitter (mobile) and multiple receivers (anchors) whose positions are known. The proposed system measures the horizontal and vertical displacement, together with known joint constraints, to estimate joint flexion/extension angles using an inverse kinematic model based on the damped least-squares technique. The performance of the proposed ultrasonic measurement system was validated against a camera-based tracking system on eight healthy subjects performing a planar squat exercise. Joint angles estimated from the ultrasonic system showed a root mean square error (RMSE) of 2.85° ± 0.57° with the reference system. Statistical analysis indicated great agreements between these two systems with a Pearson’s correlation coefficient (PCC) value larger than 0.99 for all joint angles’ estimation. These results show that the proposed ultrasonic measurement system is useful for applications, such as rehabilitation and sports.