bluuebunny/crossref_metadata_2025 huggingface dataset:
Integrated Strategies for Shipping and Terminal Development Associated With Qatar's LNG Development Strategy
Authors: Miller Douglas Scott , Richardson Andy
Published: March 2015

A key to bridging the growing distance between the gas supply and the end market is the development of the next generation of LNG tankers and the terminals needed to regasify the LNG.

As the distances increase, the shipping element of the overall project cost can have a significant impact on project economics. It has been estimated that the costs to acquire the necessary transportation could exceed the cost of the liquefaction plant. Increasing the size of these tankers from the traditional 135–140,000 m3 reduces both the initial investment (need fewer ships) as well as the unit operating costs. Qatar has led the way in working with classification societies, equipment vendors, technology licensors and builders to develop and qualify LNG Tankers with increased sizes ranging from 210,000 m3 (called QFlex) up to 265,000 m3 (called QMax) with an intermediate sized vessel approximately 243,000 m3 (called SFlex).

These vessels will also incorporate twin slow speed diesel engines and on-board re-liquefaction plants that will virtually eliminate cargo loss through LNG boil off. Qatar has developed an integrated fleet strategy that balances the economies of these next generation LNG Tankers with the flexibility desired for worldwide terminal access. Extensive and detailed port compatibility studies for these larger vessels have been conducted and continue to be revised.

To ensure liquid market access, RasGas' & Qatargas' shareholders have demonstrated a willingness to move downstream and invest both in existing as well as grass roots development in the terminals that will return the LNG to its gaseous state. This "New Era" for Qatar redefines the "Integrated Value Chain" model and completes the value chain from the Qatari wellhead to gas delivery into the consumer grid, all under the umbrella of Qatar Petroleum (QP), its partners and the LNG ventures RasGas and Qatargas.
Self-sampling for community respiratory illness: a new tool for national virological surveillance
Authors: Elliot A J , Bermingham A , Charlett A , Lackenby A , Ellis J , Sadler C , Sebastianpillai P , Powers C , Foord D , Povey E , Evans B , Durnall H , Fleming D M , Brown D , Smith G E , Zambon M
Published: March 2015

This report aims to evaluate the usefulness of self-sampling as an approach for future national surveillance of emerging respiratory infections by comparing virological data from two parallel surveillance schemes in England. Nasal swabs were obtained via self-administered sampling from consenting adults (≥?16 years-old) with influenza symptoms who had contacted the National Pandemic Flu Service (NPFS) health line during the 2009 influenza pandemic. Equivalent samples submitted by sentinel general practitioners participating in the national influenza surveillance scheme run jointly by the Royal College of General Practitioners (RCGP) and Health Protection Agency were also obtained. When comparable samples were analysed there was no significant difference in results obtained from self-sampling and clinician-led sampling schemes. These results demonstrate that self-sampling can be applied in a responsive and flexible manner, to supplement sentinel clinician-based sampling, to achieve a wide spread and geographically representative way of assessing community transmission of a known organism.
Optical schemes of spectrographs with a diffractive optical element in a converging beam
Authors: Muslimov E. R. , Pavlycheva N. K.
Published: March 2015

Optical schemes of spectrographs based on transmission concave holographic gratings working in converging beams are considered. General description of the design techniques are provided. Each of them is supported by a certain example with calculation and modeling results. In particular, it’s shown that combination of such element with a spherical wedge allows to create a spectrograph with correction of astigmatism and a variable-dispersion spectrograph.
Integrating-sphere measurements for determining optical properties of tissue-engineered oral mucosa
Authors: Ionescu A. M. , Cardona J. C. , Garzón I. , Oliveira A. C. , Ghinea R. , Alaminos M. , Pérez M. M.
Published: March 2015

Surgical procedures carried out in the oral and maxillofacial region can result in large tissue defects. Accounting for the shortage of oral mucosa to replace the excised tissues, different models of an organotypic substitute of the oral mucosa generated by tissue engineering have recently been proposed. In this work, the propagation of light radiation through artificial human oral mucosa substitutes based on fibrin-agarose scaffolds (fibrin, fibrin-0.1% agarose, fibrin-0.2%agarose) is investigated, and their optical properties are determined using the inverse adding-doubling (IAD) method based on integrating-sphere measurements. Similar values for the absorption and scattering coefficients between the fibrin and fibrin-0.1% agarose bioengineered tissues and the native oral mucosa were found. These results suggest the adequacy of these biomaterials for potential clinical use in human oral mucosa applications. These optical properties represent useful references and data for applications requiring the knowledge of the light transport through this type of tissues, applications used in clinical practice. It also provides a new method of information analysis for the quality control of the development of the artificial nanostructured oral mucosa substitutes and its comparison with native oral mucosa tissues.
Electromagnetic field intensity distribution along focal region of a metallic circular reflector covered with a plasma layer
Authors: Ghaffar A. , Alkanhal M. A. S.
Published: March 2015

Theoretical analyses has been carried out to study the deviation of the electromagnetic field intensity distribution in the focal region of a long metallic circular reflector that contains a uniform cold collisional plasma layer on its surface. The electromagnetic field intensity expressions along the focal region have been obtained using Maslov’s method. Maslov’s method is systematic procedure, which combines the simplicity of ray optics and the generality of transform methods. The derived analytical field expressions in the focal region have been solved numerically. The reflected and transmitted field intensity distributions from the plasma layer along the focal point were examined. The effects of some physical parameters such as the plasma frequency, the thickness of plasma layer and the effective collision frequency on the transmitted field intensity distribution along the focal region are studied. The results are found to be in a good agreement with results obtained using Kirchhoff’s approximation.
Flat-gain wide-band erbium doped fiber amplifier by combining two difference doped fibers
Authors: Hamida B. A. , Azooz S. M. , Jasim A. A. , Eltaif T. , Ahmad H. , Khan S. , Harun S. W.
Published: March 2015

A new erbium-doped fibre amplifier (EDFA) is demonstrated using a combination of newly developed Erbium Zirconia co-doped fiber (Zr-EDF) and the commercial silica-based Erbium-doped fiber (Si-EDF) as the gain medium. Both fibers have a very high concentration of erbium ion. A compact amplifier operating in C-band region is firstly reported using a double-pass configuration. It is shown that average gains of the proposed Zr-EDF amplifier are obtained at approximately 18 dB with a gain variation of ±2 dB within C-band region. A flat-gain and wide band operation is achieved by configuring the amplifier in two stages comprising a 2 m long Zr-EDF and 9 m long Si-EDF optimised for C- and L-band operations, respectively, in a double-pass parallel configuration. A chirp fibre Bragg grating (CFBG) is used in both stages to ensure double propagation of the signal and thus to increase the attainable gain in both C- and L-band regions. At an input signal power of 0 dBm, a flat gain of 15 dB is achieved with a gain variation of less than 0.5 dB within a wide wavelength range from 1530 to 1605 nm. The corresponding noise figure varies from 6.2 to 10.8 dB within this wavelength region.
Comparative evaluation of Carp testis as an alternative to 17 α-Methyltestosterone on Tilapia sex reversal
Authors: Khanal Nabin Babu , Shrestha M. K. , Rai Sunila , Bhujel R. C.
Published: March 2015

17 α-Methyltestosterone (MT) is a commonly used synthetic androgen for the all male tilapia fry production. The probable residual effect of MT on human health and environment has been a concern. Two trials for two seasons were conducted to evaluate the effectiveness of carp testis (CT), as a source of natural androgen, on sex reversal of Nile tilapia (Oreochromis niloticus) and compare it with MT at Department of Aquaculture, Agriculture and Forestry University, Nepal,using completely randomised block deign (RCBD). Altogether 8 treatments with 4 for methyltestosterone (40 mg MT kg-1 of diet) and 4 for 75% rohu (Labeo rohita) testis. Both source of androgen were fed for 15, 18, 21 or 24 days. Treatments were replicated thrice. The result of methyltestosterone feeding for 24 days showed significantly (p<0.05) higher percentage of male (98.5±1.5) than 15 days (87.1±3.5) but was statistically similar with 18 (91.8±2.6) and 21(94.3±3.0) days feeding. Similarly percentage of male obtained with18 (84.8 ±2.1) and 21 (85.8 ±2.9) days of CT feeding were statistically similar (p>0.05) with 24 days and also with 15 days CT treatment but the result of 24 days CT feeding was significantly higher (91.4 ±1.2)  than 15 days (82.5 ±2.7) of carp testis feeding.DOI: http://dx.doi.org/10.3126/on.v12i1.12251Our Nature (2014), 12(1): 1-7
Studies on gonadosomatic index, fecundity and hatchability of domesticated stock of asala Schizothorax richardsonii (Gray) from Nallu River of Lalitpur District
Authors: Wagle Suresh Kumar
Published: March 2015

The present work embodies studies on the reproductive capacity of captive stock of asala Schizothorax richardsonii collected from Nallu River of Lalitpur district. Gonadosomatic index (GSI) estimates ranged from 3.08±0.9% in May to 26.55±1.8% in November. Positive correlation (r=0.667) was found between egg size and GSI. The egg size (2.7 to 2.9 mm) in October and November was significantly (P<0.01) larger than the eggs measured in other months. Based on peak GSI level, S. richardsonii spawned by manual stripping in two breeding season i.e. winter (October-November) and summer (Mach-April) in Godawari (1500 masl). Mean incubation period of fertilized eggs was 259 h and 248 h during winter and summer season at 14.2 to17.5 oC and 14.5 to15.5 oC water temperature, respectively. Percent hatching rates of eggs ranged between 38 to 90% and were not significantly different (P>0.05) between breeding seasons. Overripe eggs obtained during winter season breeding (16.5%) were significantly higher (P<0.01) than the summer season breeding (3.6%).  This suggests that more frequent observation of the spawner is necessary during winter season for recognizing their appropriateness to ovulation. DOI: http://dx.doi.org/10.3126/on.v12i1.12253Our Nature (2014), 12(1): 19-27
Fish Marketing System in Southern Bangladesh: Recommendations for Efficient Marketing
Authors: Ali Mir Mohammad , Rahman Md. Mosaddequr , Hossain Md. Yeamin , Rahman Md. Zillur , Hossen Md. Alomgir , Naser S. M. Abu , Islam Rafiqul , Subba Bharat Raj , Masood Zubia , Hoque Md. Ashabul
Published: March 2015

This study aimed to explore the marketing channel, marketing cost and marketing margin and problems associated with fish marketing in order to provide recommendations for efficient fish marketing system in Barisal city, southern Bangladesh. Data were collected from seven fish markets of Barisal, southern Bangladesh including Port road fish market, Taltoli bazar fish market, Chaumatha fish market, Notullabad bus stand fish market, Kasipur bazar fish market and Bazar road fish market. Both primary and secondary data were used during 1 year study period from May, 2011 to April, 2012. Primary data were collected through field surveys and pre-structured questionnaire was used for interviewing of 10 organizers, 20 aratdars (commission agent), 50 fish traders and 100 consumers. Secondary source of information consists of published materials such as journals, textbooks, newspapers and also from interviewing different government and non-government officials and members of various fisheries related cooperative societies. The results of this study revealed 11 fish marketing channels in Barisal city’s fish marketing system. The average marketing cost ranged from 4.15% to 8.33% (6.76±0.98) % of the final retail price. The highest and lowest average fish price were recorded as USD 7.07/kg and USD 1.03/kg for giant fresh water prawn and silver carp, correspondingly. Intermediaries’ marketing margin on different species’ marketing fluctuated from 29.6% to 50.28% (39.38±5.22) % for silver carp and brown shrimp marketing, respectively. Establishment of modern fish landing center and retail markets near the fish landing port, introduction of government fish shops and  insulated and refrigerated fish vans and fish carriers, training of all personnel related to fish marketing about fish handling, quality of fish, hygiene practices, improvement of existing fish market structure, provision for government and private funding assistance for fishers/fish farmer, formulation and enactment of independent act/ordinance for fish landing and marketing are highly recommended. DOI: http://dx.doi.org/10.3126/on.v12i1.12254Our Nature (2014), 12(1): 28-36
Knowledge among mothers regarding weaning practice of Jhangad community of Jhorahat V.D.C, Nepal
Authors: Subba Dipty , Bhattarai S. , Roy R.
Published: March 2015

The study was conducted among 50 mothers of Jhangad community to assess the knowledge regarding weaning practice on infant. Although the findings showed that most of the mothers had heard about weaning practice, only 76% mothers knew about ideal weaning  time. There was a difference between the time for the initiation of weaning and selection of the food items. 92% used  foods for weaning from local sources like rice and pulses (34%) because of its easy availability. A considerable number had a concept that proper weaning helps in overall growth and development of the child. 8% replied that it helps to prevent malnutrition. Health problems like diarrhoea were the most frequent problem complained by the mothers after weaning.DOI: http://dx.doi.org/10.3126/on.v12i1.12258Our Nature (2014), 12(1): 54-59
Investigating Thermal Stability and Flame Retardant Properties of Synthesized Halloysite Nanotubes (HNT)/Ethylene Propylene Diene Monomer (EPDM) Nanocomposites
Authors: Azarmgin S. , Kaffashi B. , Davachi S. M.
Published: March 2015

In this work, Halloysite Nanotube (HNT) was synthesized, using a modified method, from kaolin clay. The scanning electron microscopy (SEM) of the synthesized HNT revealed that many of the nanotubes were tubular; however, spherical and semi-spherical, platy and semi rolled structures were also observed. Fire retardant EPDM compounds composed of typical flame retardants (FR), deca-bromo diphenyl oxide (DBDPO), antimony oxide (Sb2O3), talc and carbon black were prepared. Three elastomer compounds, with 5, 10 and 20 wt.% of synthesized HNT, and one more compound with 10 wt.% of synthesized HNT and 10 wt.% of conventional flame retardants were prepared and formed by a two roll mill. A TEM micrograph was presented to prove the well dispersion of HNT in polymer matrix. The flammability, thermal stability and tensile strength of the compounds were compared to that of typical fire retarded EPDM. The results showed that the typical flame retardants diminish the tensile strength and elongation at break of EPDM elastomers; in addition, these compounds showed the lowest thermal stability among the typical formulations. The extent of flammability of the compounds was characterized using the cone calorimetry technique. The compound containing 5 wt.% HNT showed the highest tensile strength, the least flammability and the highest thermal stability compared to the other compounds. This was related to the good dispersion and also on the tubular structure of the synthesized nanotubes. The peak of heat release rate (PHRR) and total heat release (THR) as well as the amount of hazardous gas emission for the sample having the highest mechanical response was smaller than those with conventional micro-filler flame retardants.
Effects of SEBS-g-MA on Rheology, Morphology and Mechanical Properties of PET/HDPE Blends
Authors: Dobrovszky K. , Ronkay F.
Published: March 2015

The effects of additive styrene/ethylene-butylene/styrene copolymer grafted with maleic anhydride (SEBS-g-MA) were investigated on the rheology, morphology and mechanical properties of a polyethylene terephthalate (PET)/high density polyethylene (HDPE) blend. The ratio of the two components was changed in small increments to track phase inversion. The rheology measurements show that SEBS-g-MA acts differently on HDPE and PET, as different morphologies are formed due to viscosity ratio change. With the help of electron microscopy various phases after extrusion and after injection molding were revealed and identified. Because of the high viscosity of HDPE the co-continuous morphology was immediately formed when PET reached 30 vol%. The range of the co-continuous structure of the blend was wider when SEBS-g-MA was added, and the elongation at break also improved as additive content increased, without a significant strength decrease. The divergence of the mechanical properties from the theoretical value, i.e. the value determined by the mixing rule, can be explained by the changing phase structure.
Extrusion Defects and Flow Instabilities of Molten Polymers
Authors: Vergnes B.
Published: March 2015

When certain critical conditions are exceeded, the flow of a polymer melt becomes unstable, giving rise to particular phenomena that are the subject of this review. These instabilities are a vital industrial problem, as they are the key to productivity of extrusion processes. Indeed, their onset leads to unacceptable products and is thus the upper limit of the processing conditions. They are also a fascinating scientific problem because, although studied and discussed for more than half a century, they are still not fully understood and their mechanisms are still sometimes controversial. In the present literature review, we present an overview of the studies carried out for fifty years, as well as our own opinion on the underlying mechanisms.
A Personal Perspective on the Use of Modelling Simulation for Polymer Melt Processing
Authors: Agassant J. F. , Mackley M. R.
Published: March 2015

This paper gives a personal view on the state of art in relation to the modelling of polymer melt processing. The paper briefly reviews both industrial, laboratory and modelling developments over the last forty years and highlights the key aspects now required for realistic modelling of polymer melt processing. The paper summarizes elements relating to the numerical simulation of specific and general polymer processes and also provides topical examples of the application of numerical modelling to certain commercial processes. The paper concludes with identifying areas of polymer processing that still remain a challenge in relation to accurate prediction.
Screening of chickpea genotypes against salinity stress
Authors: Shaheenuzzamn Md
Published: March 2015

The experiment was conducted during the period from December 13, 2010 to May 13, 2011 at the Crop Physiology Lab, Agronomy Division, Bangladesh Agricultural Research Institute (BARI). In Hoagland culture solution, 70 (Seventy) genotypes of chickpea were tested during germination and seedling stage at 0, 5, 10 and 15 dS/m salinity levels. Distilled water (0 dS/m) was used as a control. Germination percentage (GP), relative germination percentage (RGP), germination rate (GR), relative germination rate (RGR), root length (RL), relative root length (RRL), shoot length (SL), relative shoot length (RSL), vigor index, total dry matter (TDM) and relative total dry matter (RTDM) were found to be affected by salinity. Genotypes BD-6061, BD-6066 BD-6071, BD- 6060, BD-6067 and BD 6078 performed better at 10 dS/m and survived up to 15 days after germination as evaluated on the basis of germination percentage (GP), relative germination percentage (RGP), total dry matter (TDM) and relative total dry matter (RTDM). These genotypes could be selected for further investigation under pot culture and field evaluation in the saline area. DOI: http://dx.doi.org/10.3329/bjar.v39i4.22539 Bangladesh J. Agril. Res. 39(4): 605-619, December 2014
Study on drying kinetics of summer onion
Authors: Alam Md Masud , Islam Md Nurul , Islam Md Nazrul
Published: March 2015

The present study was concerned with the kinetics of drying of summer onion. Drying was done in a mechanical dryer at constant air flow using blanched and unblanched onion with variable temperature (52, 60 and 680C) and thickness (3, 5 and 7 mm). Drying rate was increased with increase of temperature and decreased with the increase in thickness in blanched and unblanched onion. Blanched onion showed higher drying rate than unblanched onion. Drying rate constant and thickness can be expressed as power low equations. The value of index n were found to be 1.277 and 0.845 for onion indicating that the external resistance to mass transfer was highly significant. The effect of temperature on diffusion co-efficient follows an Arrhenius type relationship. The activation energy (Ea) for diffusion of water was found 5.781 Kcal/g-mole for unblanched and 2.46 Kcal/g-mole for blanched onion when onions were dried in mechanical dryer. DOI: http://dx.doi.org/10.3329/bjar.v39i4.22545 Bangladesh J. Agril. Res. 39(4): 661-673, December 2014
Charity Shops and the Imagined Futures of Objects: How Second-Hand Markets Influence Disposal Decisions when Emptying a Parent’s House
Authors: Lovatt Melanie
Published: March 2015

This article explores the processes whereby things are donated, or not donated, to charity shops. I draw on in-depth interviews conducted with adults who have sorted through the houses of older family members who have moved into residential accommodation, and in some cases subsequently died. The affective qualities of objects and the informants’ responsibilities to be ‘good’ family members by ensuring ‘safe passage’ for their parents’ possessions worked to ensure that many objects did not enter the second hand market, but were preserved within the family or wider social networks. Competing instincts to be ‘responsible consumers’ by not keeping things unnecessarily, worked to ‘move things along’ into charity shops, where informants believed the objects could come to be valued and singularised by other people. By providing an imagined future where goods can continue to be useful and have the opportunity to extend their biographical life, I argue that charity shops and other second-hand markets can help people to dispose of objects which they do not want to keep, but which they find difficult to throw away.
Reusing Textiles: on Material and Cultural Wear and Tear
Authors: Palmsköld Anneli
Published: March 2015

Focusing on Swedish context, this article discusses contemporary practices connected to clothes and home textiles that are no longer in use, comparing them to reusing practices from the middle of the nineteenth century and onwards. The focus is on how the textiles are objects for different sorting processes in private homes as well as on a flea market, and people’s ethical concerns connected to these processes. Until the early 1970’s the skills of mending, altering and patching was common knowledge, to women at least. The reusing processes were about wear and tear considerations from a material point of view. Today there are many more clothing and home textiles items in circulation, which have to be taken care of. To handle and sort textiles seems, among other things, to be about coping with different feelings connected with guilt and bad conscience. To avoid these feelings people are seeking ways of letting the textiles circulate in order to be reused by others.
Vintage, the First 40 Years: The Emergence and Persistence of Vintage Style in the United States
Authors: Fischer Nancy L.
Published: March 2015

This paper historicizes when wearing vintage clothing first became fashionable in the United States. I trace when the trend emerges in the U.S. and explore various ways the press framed secondhand/vintage clothes and anachronistic dressing. I contend that the emergence of vintage occurs as a form of alternative consumption alongside changes that occurred in the U.S. garment industry such as outsourcing and product licensing. These changes led many consumers to seek more authentic consumption experiences. Consumers with cultural capital found in vintage an alternative market for sourcing fashionable street style. Consumers attribute characteristics to vintage clothing that are typically part of authenticity discourse such as it being of exceptional quality, original, handcrafted, made from natural fibers, and providing continuity with the past. The authenticity of vintage is symbolically deployed in opposition to contemporary mass-produced clothing and standardized retail shopping experiences.
Market Hydraulics and Subjectivities in the “Wild”: Circulations of the Flea Market
Authors: Hansson Niklas , Brembeck Helene
Published: March 2015

Since consumer researchers started paying attention to flea markets they represent common consumer and market research objects. Arguably, in the “natural laboratory” of the flea market, researchers can observe and theorize market and consumer processes “in the wild”, as forms of direct marketing and consumption. We build on existing flea market research through adopting a circulatory approach, inspired by actor-network theory (ANT). Rather than presenting a theory of (flea) markets, ANT is useful for studying markets from the perspective of grounded market-making processes. Consumption is understood as the interplay of consumers, marketers, retailers, and a wide array of artifacts and market mediators like products, economic theories and ideas, packaging, market space (in the physical sense) and furniture, etc. Our results point out that not only does such an approach enable analysis of features commonly studied within consumer research such as calculative action and social interaction, but also issues more rarely in focus in such research, such as cognitive patterns of consumer curiosity, emotions, senses, and affect. Furthermore, even though flea markets foremost are places of commerce and exchange of second hand goods, there is a large variety of other forms of flows or circulations going on “backstage” that enable the surface phenomena of second hand consumption to come into being. Many of these circulations, we argue, are material rather than immaterial Vendor and buyer subjectivities are thus understood as outcomes of circulatory dynamism that involves a range of material and immaterial flows.
B-Site Metal (Pd, Pt, Ag, Cu, Zn, Ni) Promoted La1−xSrxCo1−yFeyO3–δ Perovskite Oxides as Cathodes for IT-SOFCs
Authors: Guo Shaoli , Wu Hongjing , Puleo Fabrizio , Liotta Leonarda
Published: March 2015

Perovskite oxides La1−xSrxCo1−yFeyO3–δ (LSCF) have been extensively investigated and developed as cathode materials for intermediate temperature solid oxide fuel cells (IT-SOFCs) due to mixed ionic–electronic conductivity and high electrooxygen reduction activity for oxygen reduction. Recent literature investigations show that cathode performances can be improved by metal surface modification or B-site substitution on LSCF. Although the specific reaction mechanism needs to be further investigated, the promoting effect of metal species in enhancing oxygen surface exchange and oxygen bulk diffusion is well recognized. To our knowledge, no previous reviews dealing with the effect of metal promotion on the cathodic performances of LSCF materials have been reported. In the present review, recent progresses on metal (Pd, Pt, Ag, Cu, Zn, Ni) promotion of LSCF are discussed focusing on two main aspects, the different synthesis approaches used (infiltration, deposition, solid state reaction, one pot citrate method) and the effects of metal promotion on structural properties, oxygen vacancies content and cathodic performances. The novelty of the work lies in the fact that the metal promotion at the B-site is discussed in detail, pointing at the effects produced by two different approaches, the LSCF surface modification by the metal or the metal ion substitution at the B-site of the perovskite. Moreover, for the first time in a review article, the importance of the combined effects of oxygen dissociation rate and interfacial oxygen transfer rate between the metal phase and the cathode phase is addressed for metal-promoted LSCF and compared with the un-promoted oxides. Perspectives on new research directions are shortly given in the conclusion.
Generalized Multiscale Entropy Analysis: Application to Quantifying the Complex Volatility of Human Heartbeat Time Series
Authors: Costa Madalena , Goldberger Ary
Published: March 2015

We introduce a generalization of multiscale entropy (MSE) analysis. The method is termed MSEn, where the subscript denotes the moment used to coarse-grain a time series. MSEμ, described previously, uses the mean value (first moment). Here, we focus on MSEσ2 , which uses the second moment, i.e., the variance. MSEσ2 quantifies the dynamics of the volatility (variance) of a signal over multiple time scales. We use the method to analyze the structure of heartbeat time series. We find that the dynamics of the volatility of heartbeat time series obtained from healthy young subjects is highly complex. Furthermore, we find that the multiscale complexity of the volatility, not only the multiscale complexity of the mean heart rate, degrades with aging and pathology. The “bursty” behavior of the dynamics may be related to intermittency in energy and information flows, as part of multiscale cycles of activation and recovery. Generalized MSE may also be useful in quantifying the dynamical properties of other physiologic and of non-physiologic time series.
Modeling the Potential Distribution of Picea chihuahuana Martínez, an Endangered Species at the Sierra Madre Occidental, Mexico
Authors: Aguilar-Soto Victor , Melgoza-Castillo Alicia , Villarreal-Guerrero Federico , Wehenkel Christian , Pinedo-Alvarez Carmelo
Published: March 2015

Species distribution models (SDMs) help identify areas for the development of populations or communities to prevent extinctions, especially in the face of the global environmental change. This study modeled the potential distribution of the tree Picea chihuahuana Martínez, a species in danger of extinction, using the maximum entropy modeling method (MaxEnt) at three scales: local, state and national. We used a total of 38 presence data from the Sierra Madre Occidental. At the local scale, we compared MaxEnt with the reclassification and overlay method integrated in a geographic information system. MaxEnt generated maps with a high predictive capability (AUC > 0.97). The distribution of P. chihuahuana is defined by vegetation type and minimum temperature at national and state scales. At the local scale, both models calculated similar areas for the potential distribution of the species; the variables that better defined the species distribution were vegetation type, aspect and distance to water flows. Populations of P. chihuahuana have always been small, but our results show potential habitat greater than the area of the actual distribution. These results provide an insight into the availability of areas suitable for the species’ regeneration, possibly through assisted colonization.
Genome-Wide Identification and Analysis of Drought-Responsive Genes and MicroRNAs in Tobacco
Authors: Yin Fuqiang , Qin Cheng , Gao Jian , Liu Ming , Luo Xirong , Zhang Wenyou , Liu Hongjun , Liao Xinhui , Shen Yaou , Mao Likai , Zhang Zhiming , Lin Haijian , Lübberstedt Thomas , Pan Guangtang
Published: March 2015

Drought stress response is a complex trait regulated at transcriptional and post-transcriptional levels in tobacco. Since the 1990s, many studies have shown that miRNAs act in many ways to regulate target expression in plant growth, development and stress response. The recent draft genome sequence of Nicotiana benthamiana has provided a framework for Digital Gene Expression (DGE) and small RNA sequencing to understand patterns of transcription in the context of plant response to environmental stress. We sequenced and analyzed three Digital Gene Expression (DGE) libraries from roots of normal and drought-stressed tobacco plants, and four small RNA populations from roots, stems and leaves of control or drought-treated tobacco plants, respectively. We identified 276 candidate drought responsive genes (DRGs) with sequence similarities to 64 known DRGs from other model plant crops, 82 were transcription factors (TFs) including WRKY, NAC, ERF and bZIP families. Of these tobacco DRGs, 54 differentially expressed DRGs included 21 TFs, which belonged to 4 TF families such as NAC (6), MYB (4), ERF (10), and bZIP (1). Additionally, we confirmed expression of 39 known miRNA families (122 members) and five conserved miRNA families, which showed differential regulation under drought stress. Targets of miRNAs were further surveyed based on a recently published study, of which ten targets were DRGs. An integrated gene regulatory network is proposed for the molecular mechanisms of tobacco root response to drought stress using differentially expressed DRGs, the changed expression profiles of miRNAs and their target transcripts. This network analysis serves as a reference for future studies on tobacco response stresses such as drought, cold and heavy metals.
The Importance of G Protein-Coupled Receptor Kinase 4 (GRK4) in Pathogenesis of Salt Sensitivity, Salt Sensitive Hypertension and Response to Antihypertensive Treatment
Authors: Rayner Brian , Ramesar Raj
Published: March 2015

Salt sensitivity is probably caused by either a hereditary or acquired defect of salt excretion by the kidney, and it is reasonable to consider that this is the basis for differences in hypertension between black and white people. Dopamine acts in an autocrine/paracrine fashion to promote natriuresis in the proximal tubule and thick ascending loop of Henle. G-protein receptor kinases (or GRKs) are serine and threonine kinases that phosphorylate G protein-coupled receptors in response to agonist stimulation and uncouple the dopamine receptor from its G protein. This results in a desensitisation process that protects the cell from repeated agonist exposure. GRK4 activity is increased in spontaneously hypertensive rats, and infusion of GRK4 antisense oligonucleotides attenuates the increase in blood pressure (BP). This functional defect is replicated in the proximal tubule by expression of GRK4 variants namely p.Arg65Leu, p.Ala142Val and p.Val486Ala, in cell lines, with the p.Ala142Val showing the most activity. In humans, GRK4 polymorphisms were shown to be associated with essential hypertension in Australia, BP regulation in young adults, low renin hypertension in Japan and impaired stress-induced Na excretion in normotensive black men. In South Africa, GRK4 polymorphisms are more common in people of African descent, associated with impaired Na excretion in normotensive African people, and predict blood pressure response to Na restriction in African patients with mild to moderate essential hypertension. The therapeutic importance of the GRK4 single nucleotide polymorphisms (SNPs) was emphasised in the African American Study of Kidney Disease (AASK) where African-Americans with hypertensive nephrosclerosis were randomised to receive amlodipine, ramipril or metoprolol. Men with the p.Ala142Val genotype were less likely to respond to metoprolol, especially if they also had the p.Arg65Leu variant. Furthermore, in the analysis of response to treatment in two major hypertension studies, the 65Leu/142Val heterozygote predicted a significantly decreased response to atenolol treatment, and the 65Leu/142Val heterozygote and 486Val homozygote were associated in an additive fashion with adverse cardiovascular outcomes, independent of BP. In conclusion, there is considerable evidence that GRK4 variants are linked to impaired Na excretion, hypertension in animal models and humans, therapeutic response to dietary Na restriction and response to antihypertensive drugs. It may also underlie the difference in hypertension between different geographically derived population groups, and form a basis for pharmacogenomic approaches to treatment of hypertension.
Phenolic Composition and Antioxidant Properties of Different Peach [Prunus persica (L.) Batsch] Cultivars in China
Authors: Zhao Xiaoyong , Zhang Wenna , Yin Xueren , Su Mingshen , Sun Chongde , Li Xian , Chen Kunsong
Published: March 2015

China is an important centre of diversity for Prunus persica. In the present study, 17 Chinese peach cultivars were evaluated for phenolic content and antioxidant activity. Neochlorogenic acid (NCHA), chlorogenic acid (CHA), procyanidin B1 (B1), catechin (CAT), cyanidin-3-O-glucoside (C3G), quercetin-3-O-galactoside (Q3GAL), quercetin-3-O-glucoside (Q3GLU), quercetin-3-O-rutinoside (Q3R), and kaempferol-3-O-rutinoside (K3R) were identified and quantified. CHA and CAT were the predominant components in both the peel and pulp of this fruit. In general, peel extracts showed higher antioxidant activities than the pulp counterparts, consistent with the observed higher phenolic content. The melting peach cultivar “Xinyu” showed the highest antioxidant potency composite (APC) index. The principal component analysis (PCA) of peel phenolics showed a clear distinction between the melting peach and nectarine. Overall, peach cultivars rich in hydroxycinnamates and flavan-3-ols showed relatively higher antioxidant activities and might be excellent sources of phytochemicals and natural antioxidants.
Protective Effects of Resveratrol against UVA-Induced Damage in ARPE19 Cells
Authors: Chan Chi-Ming , Huang Cheng-Hua , Li Hsin-Ju , Hsiao Chien-Yu , Su Ching-Chieh , Lee Pei-Lan , Hung Chi-Feng
Published: March 2015

Ultraviolet radiation, especially UVA, can penetrate the lens, reach the retina, and induce oxidative stress to retinal pigment epithelial (RPE) cells. Even though it is weakly absorbed by protein and DNA, it may trigger the production of reactive oxygen species (ROS) and generate oxidative injury; oxidative injury to the retinal pigment epithelium has been implicated to play a contributory role in age-related macular degeneration (AMD). Studies showed that resveratrol, an abundant and active component of red grapes, can protect several cell types from oxidative stress. In this study, adult RPE cells being treated with different concentrations of resveratrol were used to evaluate the protective effect of resveratrol on RPE cells against UVA-induced damage. Cell viability assay showed that resveratrol reduced the UVA-induced decrease in RPE cell viability. Through flow cytometry analysis, we found that the generation of intracellular H2O2 induced by UVA irradiation in RPE cells could be suppressed by resveratrol in a concentration-dependent manner. Results of Western blot analysis demonstrated that resveratrol lowered the activation of UVA-induced extracellular signal-regulated kinase, c-jun-NH2 terminal kinase and p38 kinase in RPE cells. In addition, there was also a reduction in UVA-induced cyclooxygenase-2 (COX-2) expression in RPE cells pretreated with resveratrol. Our observations suggest that resveratrol is effective in preventing RPE cells from being damaged by UVA radiation, and is worth considering for further development as a chemoprotective agent for the prevention of early AMD.
Molecular Genetic Markers in Acute Myeloid Leukemia
Authors: Yohe Sophia
Published: March 2015

Genetics play an increasingly important role in the risk stratification and management of acute myeloid leukemia (AML) patients. Traditionally, AML classification and risk stratification relied on cytogenetic studies; however, molecular detection of gene mutations is playing an increasingly important role in classification, risk stratification, and management of AML. Molecular testing does not take the place of cytogenetic testing results, but plays a complementary role to help refine prognosis, especially within specific AML subgroups. With the exception of acute promyelocytic leukemia, AML therapy is not targeted but the intensity of therapy is driven by the prognostic subgroup. Many prognostic scoring systems classify patients into favorable, poor, or intermediate prognostic subgroups based on clinical and genetic features. Current standard of care combines cytogenetic results with targeted testing for mutations in FLT3, NPM1, CEBPA, and KIT to determine the prognostic subgroup. Other gene mutations have also been demonstrated to predict prognosis and may play a role in future risk stratification, although some of these have not been confirmed in multiple studies or established as standard of care. This paper will review the contribution of cytogenetic results to prognosis in AML and then will focus on molecular mutations that have a prognostic or possible therapeutic impact.
Photocatalytic, Morphological and Structural Properties of the TiO2-SiO2-Ag Porous Structures Based System
Authors: Kovács Gábor , Pap Zsolt , Coteț Cosmin , Coșoveanu Veronica , Baia Lucian , Danciu Virginia
Published: March 2015

TiO2-SiO2-based nanocomposites with highly porous structures are gaining ever increasing attention due to their specific properties and large variability of synthesis pathways together with wide information on the impact of the synthesis on the activity of the catalyst. This thereby offers an alternative approach to traditional/commercially available photocatalysts. In our work TiO2-SiO2 based aerogels were obtained and modified with various amount of Ag nanoparticles, using different synthesis pathways. In the first instance their photocatalytic activity was examined in detail, by observing major differences toward salicylic acid and correlating them with their morphological and structural properties (investigating their mesoporous character, band-gap values, crystallinity grade etc.). Applying different techniques such as diffuse reflectance spectroscopy (DRS), X-ray diffraction measurements (XRD), transmission electron microscopy (TEM), Raman- and X-ray photoelectron spectroscopy (XPS) the nanoparticles and their composite morphological and structural details were successfully evaluated. Major differences were observed in the activity towards salicylic acid.
Channel Structures Formed in Copper Ingots upon Melting and Evaporation by a High-Power Electron Beam
Authors: Bardakhanov Sergey , Nomoev Andrey , Schreiber Makoto , Radnaev Alexander , Salimov Rustam , Zobov Konstantin , Zavjalov Alexey , Khartaeva Erzhena
Published: March 2015

A new phenomenon is described in this paper: the formation of macroscopic channel structures on the bottom of copper ingots which were used as the target for the synthesis of copper nanoparticles by high-power electron beam evaporation and condensation. In the synthesis experiment, the cylindrical copper ingot is melted and partially evaporated in a graphite crucible. The channel structures were originally observed after a series of nanoparticle synthesis experiments in varying conditions. In the present work, various process conditions are varied in order to recreate the structures and identify their mechanism of formation. Conditions in which the channel structures form and do not form are identified and interesting microstructures are observed near the channel structures.
Targeting N-Glycan Cryptic Sugar Moieties for Broad-Spectrum Virus Neutralization: Progress in Identifying Conserved Molecular Targets in Viruses of Distinct Phylogenetic Origins
Authors: Wang Denong , Tang Jin , Tang Jiulai , Wang Lai-Xi
Published: March 2015

Identifying molecular targets for eliciting broadly virus-neutralizing antibodies is one of the key steps toward development of vaccines against emerging viral pathogens. Owing to genomic and somatic diversities among viral species, identifying protein targets for broad-spectrum virus neutralization is highly challenging even for the same virus, such as HIV-1. However, viruses rely on host glycosylation machineries to synthesize and express glycans and, thereby, may display common carbohydrate moieties. Thus, exploring glycan-binding profiles of broad-spectrum virus-neutralizing agents may provide key information to uncover the carbohydrate-based virus-neutralizing epitopes. In this study, we characterized two broadly HIV-neutralizing agents, human monoclonal antibody 2G12 and Galanthus nivalis lectin (GNA), for their viral targeting activities. Although these agents were known to be specific for oligomannosyl antigens, they differ strikingly in virus-binding activities. The former is HIV-1 specific; the latter is broadly reactive and is able to neutralize viruses of distinct phylogenetic origins, such as HIV-1, severe acute respiratory syndrome coronavirus (SARS-CoV), and human cytomegalovirus (HCMV). In carbohydrate microarray analyses, we explored the molecular basis underlying the striking differences in the spectrum of anti-virus activities of the two probes. Unlike 2G12, which is strictly specific for the high-density Man9GlcNAc2Asn (Man9)-clusters, GNA recognizes a number of N-glycan cryptic sugar moieties. These include not only the known oligomannosyl antigens but also previously unrecognized tri-antennary or multi-valent GlcNAc-terminating N-glycan epitopes (Tri/m-Gn). These findings highlight the potential of N-glycan cryptic sugar moieties as conserved targets for broad-spectrum virus neutralization and suggest the GNA-model of glycan-binding warrants focused investigation.
Short-Term Effects of a High Nitrate Diet on Nitrate Metabolism in Healthy Individuals
Authors: Bondonno Catherine , Liu Alex , Croft Kevin , Ward Natalie , Puddey Ian , Woodman Richard , Hodgson Jonathan
Published: March 2015

Dietary nitrate, through the enterosalivary nitrate-nitrite-NO pathway, can improve blood pressure and arterial stiffness. How long systemic nitrate and nitrite remain elevated following cessation of high nitrate intake is unknown. In 19 healthy men and women, the time for salivary and plasma nitrate and nitrite to return to baseline after 7 days increased nitrate intake from green leafy vegetables was determined. Salivary and plasma nitrate and nitrite was measured at baseline [D0], end of high nitrate diet [D7], day 9 [+2D], day 14 [+7D] and day 21 [+14D]. Urinary nitrite and nitrate was assessed at D7 and +14D. Increased dietary nitrate for 7 days resulted in a more than fourfold increase in saliva and plasma nitrate and nitrite (p < 0.001) measured at [D7]. At [+2D] plasma nitrite and nitrate had returned to baseline while saliva nitrate and nitrite were more than 1.5 times higher than at baseline levels. By [+7D] all metabolites had returned to baseline levels. The pattern of response was similar between men and women. Urinary nitrate and nitrate was sevenfold higher at D7 compared to +14D. These results suggest that daily ingestion of nitrate may be required to maintain the physiological changes associated with high nitrate intake.