bluuebunny/crossref_metadata_2025 huggingface dataset:
Acetylcholinesterase Inhibition and in Vitro and in Vivo Antioxidant Activities of Ganoderma lucidum Grown on Germinated Brown Rice
Authors: Hasnat Md. , Pervin Mehnaz , Lim Beong
Published: June 2013

In this study, the acetylcholinesterase inhibition and in vitro and in vivo antioxidant activities of Ganoderma lucidum grown on germinated brown rice (GLBR) were evaluated. In antioxidant assays in vitro, GLBR was found to have strong metal chelating activity, DPPH, ABTS, hydroxyl and superoxide radical scavenging activity. Cell-based antioxidant methods were used, including lipid peroxidation on brain homogenate and AAPH-induced erythrocyte haemolysis. In antioxidant assays in vivo, mice were administered with GLBR and this significantly enhanced the activities of antioxidant enzymes in the mice sera, livers and brains. The amount of total phenolic and flavonoid compounds were 43.14 mg GAE/g and 13.36 mg CE/g dry mass, respectively. GLBR also exhibited acetylcholinesterase inhibitory activity. In addition, HPLC analyses of GLBR extract revealed the presence of different phenolic compounds. These findings demonstrate the remarkable potential of GLBR extract as valuable source of antioxidants which exhibit interesting acetylcholinesterase inhibitory activity.
Eudragit® L100/N-Trimethylchitosan Chloride Microspheres for Oral Insulin Delivery
Authors: Marais Etienne , Hamman Josias , Plessis Lissinda , Lemmer Righard , Steenekamp Jan
Published: June 2013

Effective oral delivery of protein and peptide drugs remains an active topic in scientific research. In this study, matrix type microspheres were prepared with Eudragit® L100 containing N-trimethylchitosan chloride to improve the permeation of insulin across the intestinal epithelium via the paracellular pathway. Insulin loaded microspheres were initially formulated in accordance with a factorial design (23) and manufactured by means of a single water-in-oil emulsification/evaporation method. Based on external and internal morphology two microsphere formulations were selected from the initial formulations for further investigation in terms of particle size, dissolution behaviour and in vitro insulin transport across excised rat intestinal tissue. The initial eight microsphere formulations exhibited drug loading capacities ranging from 27.9–52.4% with different shapes and internal structures. The two selected microsphere formulations had average particle sizes of 157.3 ± 31.74 µm and 135.7 ± 41.05 µm, respectively, and mean dissolution time values for insulin release of 34.47 and 42.63 min, respectively. In vitro transport of insulin across excised rat intestinal tissue from the two selected microsphere formulations was 10.67–fold and 9.68–fold higher than the control group (insulin alone). The microsphere delivery system prepared from Eudragit® L100 containing N-trimethylchitosan chloride is therefore a promising candidate for effective oral insulin delivery.
The Development of Aromas in Ruminant Meat
Authors: Resconi Virginia , Escudero Ana , Campo María
Published: June 2013

This review provides an update on our understanding of the chemical reactions (lipid oxidation, Strecker and Maillard reactions, thiamine degradation) and a discussion of the principal aroma compounds derived from those reaction or other sources in cooked meat, mainly focused on ruminant species. This knowledge is essential in order to understand, control, and improve the quality of food products. More studies are necessary to fully understand the role of each compound in the overall cooked meat flavour and their possible effect in consumer acceptability.
Exploring the C-X…π Halogen Bonding Motif: An Infrared and Raman Study of the Complexes of CF3X (X = Cl, Br and I) with the Aromatic Model Compounds Benzene and Toluene
Authors: Nagels Nick , Hauchecorne Dieter , Herrebout Wouter
Published: June 2013

The formation of halogen bonded complexes formed between the trifluorohalomethanes CF3Cl, CF3Br and CF3I and the Lewis bases benzene and toluene at temperatures below 150K was investigated using FTIR and Raman spectroscopy. Experiments using liquid krypton as solvent show that for both CF3Br and CF3I substantial fractions of the monomers can be involved in 1:1 complexes. In addition, weak absorptions illustrating the formation of 2:1 complexes between CF3I and benzene are observed. Using spectra recorded at temperatures between 120 and 140 K, observed information on the relative stability was obtained for all complexes by determining the complexation enthalpies in solution. The resulting values for CF3Br.benzene, CF3I.benzene and (CF3I)2.benzene are −6.5(3), −7.6(2) and −14.5(9) kJ mol−1. The values for CF3Br.toluene and CF3I.toluene are −6.2(5) and −7.4(5) kJ mol−1. The experimental complexation enthalpies are compared with theoretical data obtained by combining results from MP2/aug-cc-pVDZ(-PP) and MP2/aug-cc-pVTZ(-PP) ab initio calculations, from statistical thermodynamical calculations and from Monte Carlo Free Energy Perturbation simulations. The data are also compared with results derived for other C-X···π halogen bonded complexes involving unsaturated Lewis bases such as ethene and ethyne.
Design, Synthesis and Evaluation of the Antibacterial Enhancement Activities of Amino Dihydroartemisinin Derivatives
Authors: Wu Chong , Liu Jian , Pan Xichun , Xian Wenying , Li Bin , Peng Wei , Wang Jingfang , Yang Dacheng , Zhou Hong
Published: June 2013

Artemisinin (ART) and its derivatives artesunate (AS), dihydroartemisinin (DHA) are a group of drugs containing a sesquiterpene lactone used to treat malaria. Previously, AS was shown to not have antibacterial activity but to significantly increase the antibacterial activities of β-lactam antibiotics against E. coli. Herein, molecular docking experiments showed that ART, AS and DHA could dock into AcrB very well, especially DHA and AS; both DHA and AS had the same docking pose. The affinity between AS and AcrB seemed weaker than that of DHA, while the succinate tail of AS, which was like a “bug”, could extend in the binding pocket very well. Imitating the parent nucleus of DHA and the succinate tail of AS, twenty-one DHA derivatives 4a–u were designed and synthesized. Among them, seventeen were new compounds. The synergistic effects against E. coli AG100A/pET28a-AcrB showed among the new structures 4k, 4l, 4m, 4n, and 4r exhibited significant synergism with β-lactam antibiotics although they had no direct antibacterial activities themelves. The bacterial growth assay showed that only 4k in combination with ampicillin or cefuroxime could totally inhibit bacterial growth from 0 to 12 h, demonstrating that 4k had the best antibacterial enhancement effect. In conclusion, our results provided a new idea and several candidate compounds for antibacterial activity enhancers against multidrug resistant E. coli.
Preliminary Biological Evaluation of Novel 99mTc-Cys-Annexin A5 as a Apoptosis Imaging Agent
Authors: Lu Chunxiong , Jiang Quanfu , Hu Minjin , Tan Cheng , Ji Yu , Yu Huixin , Hua Zichun
Published: June 2013

A novel annexin A5 derivative (cys-annexin A5) with a single cysteine residue at its C-terminal has been developed and successfully labeled in high labeling yield with 99mTc by a ligand exchange reaction. Like the 1st generation 99mTc-HYNIC-annexin A5, the novel 99mTc-cys-annexin A5 derivative shows in normal mice mainly renal and, to a lesser extent, hepatobiliary excretion. In rat models of hepatic apoptosis there was 283% increase in hepatic uptake of 99mTc-cys-annexin A5 as compared to normal mice. The results indicate that the novel 99mTc-cys-annexin A5 is a potential apoptosis imaging agent.
Effects of Vitamin D3 and Paricalcitol on Immature Cardiomyocytes: A Novel Role for Vitamin D Analogs in the Prevention of Cardiovascular Diseases
Authors: Pacini Stefania , Morucci Gabriele , Branca Jacopo , Aterini Stefano , Amato Marcello , Gulisano Massimo , Ruggiero Marco
Published: June 2013

Cardiovascular diseases are more prevalent in patients with chronic kidney disease than in the general population and they are considered the leading cause of death in patients with end-stage renal disease. The discovery that vitamin D3 plays a considerable role in cardiovascular protection has led, in recent years, to an increase in the administration of therapies based on the use of this molecule; nevertheless, several studies warned that an excess of vitamin D3 may increase the risk of hypercalcemia and vascular calcifications. In this study we evaluated the effects of vitamin D3, and of its selective analog paricalcitol, on immature cardiomyocytes. Results show that vitamin D3 induces cAMP-mediated cell proliferation and significant intracellular calcification. Paricalcitol, however, induces cell differentiation, morphological modifications in cell shape and size, and no intracellular calcification. Furthermore, vitamin D3 and paricalcitol differently affect cardiomyoblasts responses to acetylcholine treatment. In conclusion, our results demonstrate that the effects of vitamin D3 and paricalcitol on cardiomyoblasts are different and, if these in vitro observations could be extrapolated in vivo, they suggest that paricalcitol has the potential for cardiovascular protection without the risk of inducing intracellular calcification.
Can We Prevent Antimicrobial Resistance by Using Antimicrobials Better?
Authors: Soothill Germander , Hu Yanmin , Coates Anthony
Published: June 2013

Since their development over 60 years ago, antimicrobials have become an integral part of healthcare practice worldwide. Recently, this has been put in jeopardy by the emergence of widespread antimicrobial resistance, which is one of the major problems facing modern medicine. In the past, the development of new antimicrobials kept us one step ahead of the problem of resistance, but only three new classes of antimicrobials have reached the market in the last thirty years. A time is therefore approaching when we may not have effective treatment against bacterial infections, particularly for those that are caused by Gram-negative organisms. An important strategy to reduce the development of antimicrobial resistance is to use antimicrobials more appropriately, in ways that will prevent resistance. This involves a consideration of the pharmacokinetic and pharmacodynamics properties of antimicrobials, the possible use of combinations, and more appropriate choice of antimicrobials, which may include rapid diagnostic testing and antimicrobial cycling. Examples given in this review include Mycobacterium tuberculosis, Gram-negative and Gram-positive organisms. We shall summarise the current evidence for these strategies and outline areas for future development.
Photocrosslinkable Star Polymers via RAFT-Copolymerizations with N-Ethylacrylate-3,4-dimethylmaleimide
Authors: Förster Nadja , Pöppler Ann-Christin , Stalke Dietmar , Vana Philipp
Published: June 2013

This paper describes the Z-RAFT-star copolymerization of n-butyl acrylate (BA) and N-isopropyl acrylamide (NIPAm), respectively, with N-ethylacrylate-3,4-dimethylmaleimide (1.1), a monomer carrying a UV-reactive unit that undergoes photocrosslinking. Addition of 1.1 slows down the polymerization rate both for BA and for NIPAm polymerization. Double star formation due to radical attack to the 3,4-dimethylmaleimide moiety was found in the case of BA. Dead polymer formation, presumably due to aminolysis as side-reaction, was pronounced in the NIPAm system. These two effects broadened the molar mass distributions, but did not impede the formation of functional star polymers. The composition of the copolymers as well as the reactivity ratios for the applied comonomers were determined via NMR spectroscopy (BA-co-1.1 r1.1 = 2.24 rBA = 0.95; NIPAm-co-1.1 r1.1 = 0.96 rNIPAm = 0.05). In both cases, the comonomer is consumed preferably in the beginning of the polymerization, thus forming gradient copolymer stars with the UV-reactive units being located in the outer sphere.
A Multiscale Mechanical Model for Plant Tissue Stiffness
Authors: Faisal Tanvir , Rey Alejandro , Pasini Damiano
Published: June 2013

Plant petioles and stems are hierarchical cellular structures, displaying structuralfeatures defined at multiple length scales. The current work focuses on the multi-scalemodelling of plant tissue, considering two orders of structural hierarchy, cell wall and tissue.The stiffness of plant tissue is largely governed by the geometry of the tissue cells, thecomposition of the cell wall and the structural properties of its constituents. The cell wallis analogous to a fiber reinforced composite, where the cellulose microfibril (CMF) is theload bearing component. For multilayered cell wall, the microfibril angle (MFA) in themiddle layer of the secondary cell wall (S2 layer) largely affects the longitudinal stiffnessfor values up to 40o. The MFA in turn influences the overall wall stiffness. In this work,the effective stiffness of a model system based on collenchyma cell wall of a dicotyledonousplant, the Rheum rhabarbarum, is computed considering generic MFA and volume fractions.At the cellular level, a 2-D Finite Edge Centroidal Voronoi tessellation (FECVT) has beendeveloped and implemented to generate the non-periodic microstructure of the plant tissue.The effective elastic properties of the cellular tissue are obtained through finite elementanalysis (FEA) of the Voronoi model coupled with the cell wall properties. The stiffness ofthe hierarchically modeled tissue is critically important in determining the overall structuralproperties of plant petioles and stems.
Satellite-Based Sunshine Duration for Europe
Authors: Kothe Steffen , Good Elizabeth , Obregón André , Ahrens Bodo , Nitsche Helga
Published: June 2013

In this study, two different methods were applied to derive daily and monthly sunshine duration based on high-resolution satellite products provided by the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) Satellite Application Facility on Climate Monitoring using data from Meteosat Second Generation (MSG) SEVIRI (Spinning Enhanced Visible and Infrared Imager). The satellite products were either hourly cloud type or hourly surface incoming direct radiation. The satellite sunshine duration estimates were not found to be significantly different using the native 15-minute temporal resolution of SEVIRI. The satellite-based sunshine duration products give additional spatial information over the European continent compared with equivalent in situ-based products. An evaluation of the satellite sunshine duration by product intercomparison and against station measurements was carried out to determine their accuracy. The satellite data were found to be within ±1 h/day compared to high-quality Baseline Surface Radiation Network or surface synoptic observations (SYNOP) station measurements. The satellite-based products differ more over the oceans than over land, mainly because of the treatment of fractional clouds in the cloud type-based sunshine duration product. This paper presents the methods used to derive the satellite sunshine duration products and the performance of the different retrievals. The main benefits and disadvantages compared to station-based products are also discussed.
Theoretical Analysis of the Optical Propagation Characteristics in a Fiber-Optic Surface Plasmon Resonance Sensor
Authors: Liu Linlin , Yang Jun , Yang Zhong , Wan Xiaoping , Hu Ning , Zheng Xiaolin
Published: June 2013

Surface plasmon resonance (SPR) sensor is widely used for its high precision and real-time analysis. Fiber-optic SPR sensor is easy for miniaturization, so it is commonly used in the development of portable detection equipment. It can also be used for remote, real-time, and online detection. In this study, a wavelength modulation fiber-optic SPR sensor is designed, and theoretical analysis of optical propagation in the optical fiber is also done. Compared with existing methods, both the transmission of a skew ray and the influence of the chromatic dispersion are discussed. The resonance wavelength is calculated at two different cases, in which the chromatic dispersion in the fiber core is considered. According to the simulation results, a novel multi-channel fiber-optic SPR sensor is likewise designed to avoid defaults aroused by the complicated computation of the skew ray as well as the chromatic dispersion. Avoiding the impact of skew ray can do much to improve the precision of this kind of sensor.
A Proposal for Modeling Real Hardware, Weather and Marine Conditions for Underwater Sensor Networks
Authors: Climent Salvador , Capella Juan , Blanc Sara , Perles Angel , Serrano Juan
Published: June 2013

Network simulators are useful for researching protocol performance, appraising new hardware capabilities and evaluating real application scenarios. However, these tasks can only be achieved when using accurate models and real parameters that enable the extraction of trustworthy results and conclusions. This paper presents an underwater wireless sensor network ecosystem for the ns-3 simulator. This ecosystem is composed of a new energy-harvesting model and a low-cost, low-power underwater wake-up modem model that, alongside existing models, enables the performance of accurate simulations by providing real weather and marine conditions from the location where the real application is to be deployed.
The Localized Discovery and Recovery for Query Packet Losses in Wireless Sensor Networks with Distributed Detector Clusters
Authors: Teng Rui , Leibnitz Kenji , Miura Ryu
Published: June 2013

An essential application of wireless sensor networks is to successfully respond to user queries. Query packet losses occur in the query dissemination due to wireless communication problems such as interference, multipath fading, packet collisions, etc. The losses of query messages at sensor nodes result in the failure of sensor nodes reporting the requested data. Hence, the reliable and successful dissemination of query messages to sensor nodes is a non-trivial problem. The target of this paper is to enable highly successful query delivery to sensor nodes by localized and energy-efficient discovery, and recovery of query losses. We adopt local and collective cooperation among sensor nodes to increase the success rate of distributed discoveries and recoveries. To enable the scalability in the operations of discoveries and recoveries, we employ a distributed name resolution mechanism at each sensor node to allow sensor nodes to self-detect the correlated queries and query losses, and then efficiently locally respond to the query losses. We prove that the collective discovery of query losses has a high impact on the success of query dissemination and reveal that scalability can be achieved by using the proposed approach. We further study the novel features of the cooperation and competition in the collective recovery at PHY and MAC layers, and show that the appropriate number of detectors can achieve optimal successful recovery rate. We evaluate the proposed approach with both mathematical analyses and computer simulations. The proposed approach enables a high rate of successful delivery of query messages and it results in short route lengths to recover from query losses. The proposed approach is scalable and operates in a fully distributed manner.
Deployment and Validation of a Smart System for Screening of Language Disorders in Primary Care
Authors: Martín-Ruiz María , Valero Duboy Miguel Angel , Pau de la Cruz Iván
Published: June 2013

Neuro-evolutive development from birth until the age of six years is a decisive factor in a child’s quality of life. Early detection of development disorders in early childhood can facilitate necessary diagnosis and/or treatment. Primary-care pediatricians play a key role in its detection as they can undertake the preventive and therapeutic actions requested to promote a child’s optimal development. However, the lack of time and little specific knowledge at primary-care avoid to applying continuous early-detection anomalies procedures. This research paper focuses on the deployment and evaluation of a smart system that enhances the screening of language disorders in primary care. Pediatricians get support to proceed with early referral of language disorders. The proposed model provides them with a decision-support tool for referral actions to trigger essential diagnostic and/or therapeutic actions for a comprehensive individual development. The research was conducted by starting from a sample of 60 cases of children with language disorders. Validation was carried out through two complementary steps: first, by including a team of seven experts from the fields of neonatology, pediatrics, neurology and language therapy, and, second, through the evaluation of 21 more previously diagnosed cases. The results obtained show that therapist positively accepted the system proposal in 18 cases (86%) and suggested system redesign for single referral to a speech therapist in three remaining cases.
Accurate Human Tissue Characterization for Energy-Efficient Wireless On-Body Communications
Authors: Vallejo Mónica , Recas Joaquín , Del Valle Pablo , Ayala José
Published: June 2013

The demand for Wireless Body Sensor Networks (WBSNs) is rapidly increasing due to the revolution in wearable systems demonstrated by the penetration of on-the-body sensors in hospitals, sports medicine and general health-care practices. In WBSN, the body acts as a communication channel for the propagation of electromagnetic (EM) waves, where losses are mainly due to absorption of power in the tissue. This paper shows the effects of the dielectric properties of biological tissues in the signal strength and, for the first time, relates these effects with the human body composition. After a careful analysis of results, this work proposes a reactive algorithm for power transmission to alleviate the effect of body movement and body type. This policy achieves up to 40.8% energy savings in a realistic scenario with no performance overhead.
Aspects of the Application of Cavity Enhanced Spectroscopy to Nitrogen Oxides Detection
Authors: Wojtas Jacek , Mikolajczyk Janusz , Bielecki Zbigniew
Published: June 2013

This article presents design issues of high-sensitive laser absorption spectroscopy systems for nitrogen oxides (NOx) detection. Examples of our systems and their investigation results are also described. The constructed systems use one of the most sensitive methods, cavity enhanced absorption spectroscopy (CEAS). They operate at different wavelength ranges using a blue—violet laser diode (410 nm) as well as quantum cascade lasers (5.27 µm and 4.53 µm). Each of them is configured as a one or two channel measurement device using, e.g., time division multiplexing and averaging. During the testing procedure, the main performance features such as detection limits and measurements uncertainties have been determined. The obtained results are 1 ppb NO2, 75 ppb NO and 45 ppb N2O. For all systems, the uncertainty of concentration measurements does not exceed a value of 13%. Some experiments with explosives are also discussed. A setup equipped with a concentrator of explosives vapours was used. The detection method is based either on the reaction of the sensors to the nitrogen oxides directly emitted by the explosives or on the reaction to the nitrogen oxides produced during thermal decomposition of explosive vapours. For TNT, PETN, RDX and HMX a detection limit better than 1 ng has been achieved.
The Pore-Forming Haemolysins of Bacillus Cereus: A Review
Authors: Ramarao Nalini , Sanchis Vincent
Published: June 2013

The Bacillus cereus sensu lato group contains diverse Gram-positive spore-forming bacteria that can cause gastrointestinal diseases and severe eye infections in humans. They have also been incriminated in a multitude of other severe, and frequently fatal, clinical infections, such as osteomyelitis, septicaemia, pneumonia, liver abscess and meningitis, particularly in immuno-compromised patients and preterm neonates. The pathogenic properties of this organism are mediated by the synergistic effects of a number of virulence products that promote intestinal cell destruction and/or resistance to the host immune system. This review focuses on the pore-forming haemolysins produced by B. cereus: haemolysin I (cereolysin O), haemolysin II, haemolysin III and haemolysin IV (CytK). Haemolysin I belongs to the cholesterol-dependent cytolysin (CDC) family whose best known members are listeriolysin O and perfringolysin O, produced by L. monocytogenes and C. perfringens respectively. HlyII and CytK are oligomeric ß-barrel pore-forming toxins related to the α-toxin of S. aureus or the ß-toxin of C. perfringens. The structure of haemolysin III, the least characterized haemolytic toxin from the B. cereus, group has not yet been determined.
Viral and Host Factors Required for Avian H5N1 Influenza A Virus Replication in Mammalian Cells
Authors: Zhang Hong , Hale Benjamin , Xu Ke , Sun Bing
Published: June 2013

Following the initial and sporadic emergence into humans of highly pathogenic avian H5N1 influenza A viruses in Hong Kong in 1997, we have come to realize the potential for avian influenza A viruses to be transmitted directly from birds to humans. Understanding the basic viral and cellular mechanisms that contribute to infection of mammalian species with avian influenza viruses is essential for developing prevention and control measures against possible future human pandemics. Multiple physical and functional cellular barriers can restrict influenza A virus infection in a new host species, including the cell membrane, the nuclear envelope, the nuclear environment, and innate antiviral responses. In this review, we summarize current knowledge on viral and host factors required for avian H5N1 influenza A viruses to successfully establish infections in mammalian cells. We focus on the molecular mechanisms underpinning mammalian host restrictions, as well as the adaptive mutations that are necessary for an avian influenza virus to overcome them. It is likely that many more viral and host determinants remain to be discovered, and future research in this area should provide novel and translational insights into the biology of influenza virus-host interactions.
Resistance to Tenofovir-Based Regimens during Treatment Failure of Subtype C HIV-1 in South Africa
Authors: Hoffmann Christopher J , Ledwaba Johanna , Li Jin-fen , Johnston Victoria , Hunt Gillian , Fielding Katherine L , Chaisson Richard E , Churchyard Gavin J , Grant Alison D , Johnson Jeffrey A , Charalambous Salome , Morris Lynn
Published: June 2013

Background

Tenofovir disoproxil fumarate (TDF) is increasingly available for patients infected with subtype C HIV-1. This subtype is reported to develop the principal TDF resistance mutation in the HIV reverse transcriptase, K65R, with greater propensity than other subtypes. We sought to describe K65R development during TDF use in a cohort of patients infected with subtype C HIV.

Methods

Using a prospectively followed cohort with 6 monthly HIV RNA assays, we identified virological failure (defined as an HIV RNA>1,000 copies/ml) during treatment that included TDF. Residual serum, stored at the time of the HIV RNA assay, was used for consensus sequencing and allele-specific PCR. We assessed prevalence of resistance at failure during TDF-containing treatment and associated factors.

Results

Among 1,682 patients on a TDF-containing regimen, 270 developed failure of which 40 were assessed for resistance. By sequencing, the K65R was identified in 5 (12%), major non-nucleoside reverse transcriptase inhibitor mutations in 24 (57%) and the M184V/I in 12 (28%) patients. The K65R was associated with lower HIV RNA at failure (HIV RNA 3.3 versus 4.2 log10 copies/ml) and prior stavudine exposure. An additional five patients had minority K65R populations identified by allele-specific PCR.

Conclusions

These data suggest that the K65R prevalence at virological failure is moderately higher in our subtype C population than some non-subtype C HIV cohorts. However, we did not find that the K65R was highly selected in HIV-1 subtype-C-infected patients with up to 6 months of failure of a TDF-containing regimen.
Myocardial Deformation Imaging and Rare Cardiomyopathies with Hypertrophic Phenotype: A Review Focused on Fabry Disease, Friedreich Ataxia and Amyloidosis
Authors: Fadel Bahaa , Baldini Luca , Pergola Valeria , Al Bulbul Ziad , Di Salvo Giovanni
Published: June 2013

Tissue Doppler and deformation imaging, including Doppler-derived strain and speckle tracking, have significantly improved our understanding of cardiac mechanics in both physiological and pathological states. The various modes of left ventricular deformation (longitudinal, circumferential, radial and twist) leading to systolic contraction can nowadays be quantified. One of the best applications of deformation imaging is in the area of hypertrophic cardiomyopathies. Deformation imaging allows the evaluation of global and regional myocardial performance and the noninvasive characterization of abnormal intramural myocardial mechanics. In this review, we discuss the role of myocardial deformation imaging derived by echocardiography in the assessment of rare hypertrophic phenotype including Fabry disease, Friedreich ataxia and amyloidosis. Deformation imaging allows for early identification of myocardial dysfunction in many hypertrophic disorders, at an earlier stage than that provided by standard imaging or echocardiographic techniques. This allows for the implementation of appropriate therapy before significant disease progression has occurred and prior to the development of advanced myocardial fibrosis. Thus therapy would likely be more effective and may potentially lead to improvement in patient outcome. Additionally strain imaging allows to better monitoring the efficacy of therapy by assessing the progression and regression of myocardial involvement. Finally, findings on strain imaging carry important prognostic information in many hypertrophic disorders.
Mental health functioning among men who use the Internet specifically to find partners for unprotected sex
Authors: Klein Hugh
Published: June 2013

Previous studies have shown a link between mental health functioning and involvement in HIV risk practices. The present research examines how well one specific group of men who have sex with other men (MSM) fare in terms of their mental health functioning, and then focuses on how mental health functioning relates to HIV risk practices in this population. The study was based on a national random sample of 332 MSM who use the Internet to seek men with whom they can engage in unprotected sex. Data collection was conducted via telephone interviews between January 2008 and May 2009. Depression is more common among men in this population than in the adult male population-at-large. All other measures of mental health functioning that were examined (self-esteem, impulsivity, current life satisfaction, optimism about the future) indicated low rates of mental health problem. Contrary to expectations, in nearly all instances, mental health functioning was not related to HIV risk practices. More work needs to be done to understand the causes of depression among these men, and to assess how, if at all, depression relates to risk practices in this population. These findings suggest that factors other than mental health problems must be considered if one wishes to understand HIV risk taking in this population.
Missional ecclesiology as basis for a new church order: A case study
Authors: Dreyer Wim A.
Published: June 2013

In this contribution the author looks at the ecclesiology and church polity of the Nederduitsch Hervormde Kerk van Afrika (NHKA) as a case study. Different approaches to ecclesiology and church polity by different NHKA theologians are examined. The conclusion is reached that a paradigm shift is required, to assist the church in the process of transformation. Part of the transformation process, is the creation of a church order with a stronger missional orientation. It is argued that, in the context of the 21st century, the missio Dei paradigm and missional ecclesiology could be a suitable point of departure in the creation of a new church order for the NHKA.
Survival of the scorpion Opistophthalmus pugnax (Scorpionidae) after exposure to a lethal dosage SO2 gas.
Authors: Van Aardt Willie J.
Published: June 2013

Scorpions are well known for their ability to adapt to dry habitats, scarcity of food and radioactive radiation. Nothing is known about their response to toxic gases. Results from this experiment showed that a high dose of 1000 parts per million SO2 was not lethal for Opistophthalmus pugnax; compare this to humans who cannot tolerate and survive high SO2 levels. In fact, the oxygen production rate increased from 4.16 µmol/g-1hour-1 to 7.69 µmol/g-1hour-1 after exposure of one hour to SO2. Forty minutes after exposure, ṀO2 was still nearly twice as high compared with the ṀO2 value at the beginning. Further experiments are suggested to solve the problem of possible spiracle occlusion caused by SO2.
Size, Order, and Connected Domination
Authors: Mukwembi Simon
Published: June 2013

We give a sharp upper bound on the size of a triangle-free graph of a given order and connected domination. Our bound, apart from strengthening an old classical theorem of Mantel and of Turén improves on a theorem of Sanchis. Further, as corollaries, we settle a long standing conjecture of Graffiti on the leaf number and local independence for triangle-free graphs and answer a question of Griggs, Kleitman, and Shastri on a lower bound of the leaf number in triangle-free graphs.
Platelet-Rich Plasma in Cosmetic Surgery
Authors: Seth Rahul , Kang Robert S , Lee Matthew K , Keller Gregory S
Published: June 2013

Platelet-rich plasma (PRP) is blood plasma containing an above baseline level of platelets and growth factors. PRP is an emerging new treatment utilized to enhance wound healing and has been in clinical use over the last several decades within many disciplines, such as orthopedic, oral-maxillofacial and cardiac surgery. Recently, PRP has come to the attention of esthetic surgeons, with burgeoning new applications ranging from hair restoration to soft tissue augmentation. The goal of this review is to describe the current body of literature on PRP as it pertains to the field of esthetics, and to review its current real-world applications. PRP's utility in cosmetic surgery is rapidly growing and offers a promising and exciting new therapeutic modality.

How to cite this article

Kang RS, Lee MK, Seth R, Keller GS. Platelet-Rich Plasma in Cosmetic Surgery. Int J Otorhinolaryngol Clin 2013;5(1):24-28.
Large-eddy simulation of organized precipitating trade wind cumulus clouds
Authors: Seifert A. , Heus T.
Published: June 2013

Abstract. Trade wind cumulus clouds often organize in along-wind cloud streets and across-wind mesoscale arcs. We present a benchmark large-eddy simulation which resolves the individual clouds as well as the mesoscale organization on scales of O(10 km). Different methods to quantify organization of cloud fields are applied and discussed. Using perturbed physics large-eddy simulation experiments, the processes leading to the formation of cloud clusters and the mesoscale arcs are revealed. We find that both cold pools as well as the sub-cloud layer moisture field are crucial to understand the organization of precipitating shallow convection. Further sensitivity studies show that microphysical assumptions can have a pronounced impact on the onset of cloud organization.
Forcing of stratospheric chemistry and dynamics during the Dalton Minimum
Authors: Anet J. G. , Muthers S. , Rozanov E. , Raible C. C. , Peter T. , Stenke A. , Shapiro A. I. , Beer J. , Steinhilber F. , Brönnimann S. , Arfeuille F. , Brugnara Y. , Schmutz W.
Published: June 2013

Abstract. The response of atmospheric chemistry and climate to volcanic eruptions and a decrease in solar activity during the Dalton Minimum is investigated with the fully coupled atmosphere-ocean-chemistry general circulation model SOCOL-MPIOM covering the time period 1780 to 1840 AD. We carried out several sensitivity ensemble experiments to separate the effects of (i) reduced solar ultra-violet (UV) irradiance, (ii) reduced solar visible and near infrared irradiance, (iii) enhanced galactic cosmic ray intensity as well as less intensive solar energetic proton events and auroral electron precipitation, and (iv) volcanic aerosols. The introduced changes of UV irradiance and volcanic aerosols significantly influence stratospheric climate in the early 19th century, whereas changes in the visible part of the spectrum and energetic particles have smaller effects. A reduction of UV irradiance by 15% causes global ozone decrease below the stratopause reaching 8% in the midlatitudes at 5 hPa and a significant stratospheric cooling of up to 2 °C in the midstratosphere and to 6 °C in the lower mesosphere. Changes in energetic particle precipitation lead only to minor changes in the yearly averaged temperature fields in the stratosphere. Volcanic aerosols heat the tropical lower stratosphere allowing more water vapor to enter the tropical stratosphere, which, via HOx reactions, decreases upper stratospheric and mesospheric ozone by roughly 4%. Conversely, heterogeneous chemistry on aerosols reduces stratospheric NOx leading to a 12% ozone increase in the tropics, whereas a decrease in ozone of up to 5% is found over Antarctica in boreal winter. The linear superposition of the different contributions is not equivalent to the response obtained in a simulation when all forcing factors are applied during the DM – this effect is especially well visible for NOx/NOy. Thus, this study highlights the non-linear behavior of the coupled chemistry-climate system. Finally, we conclude that especially UV and volcanic eruptions dominate the changes in the ozone, temperature and dynamics while the NOx field is dominated by the EPP. Visible radiation changes have only very minor effects on both stratospheric dynamics and chemistry.
SAGE version 7.0 algorithm: application to SAGE II
Authors: Damadeo R. P. , Zawodny J. M. , Thomason L. W. , Iyer N.
Published: June 2013

Abstract. This paper details the SAGE version 7.0 algorithm and how it is applied to SAGE II. Changes made between the previous (v6.2) and current (v7.0) versions are described and their impacts on the data products explained for both coincident event comparisons and time-series analysis. Users of the data will notice a general improvement in all of the SAGE II data products, which are now in better agreement with more modern data sets (e.g. SAGE III) and more robust for use with trend studies.
Do successive climate extremes weaken the resistance of plant communities? An experimental study using plant assemblages
Authors: Dreesen F. E. , De Boeck H. J. , Janssens I. A. , Nijs I.
Published: June 2013

Abstract. The probability that plant communities undergo successive climate extremes increases under climate change. Exposure to an extreme event might elicit acclimatory responses and thereby greater resistance to a subsequent event, but might also reduce resistance if the recovery period is too short or resilience too low. Using experimental plant assemblages, we compared the effects of two successive extremes (either two drought extremes, two heat extremes or two drought + heat extremes) to those of assemblages being exposed only to the second extreme. Additionally, the recovery period between the successive extremes was varied (2, 3.5 or 6 weeks). Among the different types of climate extremes, combined drought + heat extremes induced substantial leaf and plant mortality, while the effects of drought and heat extremes were smaller. Preceding drought + heat extremes lowered the resistance in terms of leaf survival to a subsequent drought + heat extreme if the recovery period was 2 weeks, even though the leaves had completely recovered during that interval. No reduced resistance to subsequent extremes was recorded with longer recovery times or with drought or heat extremes. Despite mortality on the short term, the drought + heat and the heat extremes increased the end-of-season aboveground biomass, independent of the number of events or the recovery period. These results show that the effect of a preceding extreme event disappears quite quickly, but that recurrent climate extremes with short time intervals can weaken the resistance of herbaceous plant assemblages. This can however be compensated afterwards through rapid recovery and secondary, positive effects in the longer term.
Soil moisture modifies the response of soil respiration to temperature in a desert shrub ecosystem
Authors: Wang B. , Zha T. S. , Jia X. , Wu B. , Zhang Y. Q. , Qin S. G.
Published: June 2013

Abstract. The response of soil respiration (Rs) to soil temperature and moisture have been well documented in forests, but data and information from desert shrub ecosystems are limited. Soil CO2 efflux from a desert shrub ecosystem was measured continuously with automated chambers in Ningxia, northwest China, from June to October 2012. The responses of Rs to Ts was strongly affected diurnally by soil moisture, with the diel variation in Rs being strongly related to 10 cm soil temperature (Ts) at moderate and high soil volumetric water content (VWC), but less related to Ts at low VWC. Ts typically lagged Rs by 3–4 h, however, the lag time varied in relation to VWC, with increased lag times at low VWC. Over the seasonal cycle, daily mean Rs was positively correlated with Ts when VWC exceeded 0.08 m3 m−3, but became decoupled from Ts when VWC dropped below this threshold. The annual temperature sensitivity of Rs (Q10) was 1.5. The short-term sensitivity of Rs to Ts, computed using three-day windows, varied significantly over the seasonal cycle; the short-term Q10 was negatively correlated with Ts and positively correlated with VWC. These results suggest the potential for a negative feedback to climate warming in desert ecosystems, related to the impact of low soil moisture on Rs. The results highlight the biological causes of diel hysteresis between Rs and Ts and the need for carbon cycle models to account for the interacting effects of Ts and VWC as joint determinants of Rs in desert ecosystem.
Environmental controls on the Emiliania huxleyi calcite mass
Authors: Horigome M. T. , Ziveri P. , Grelaud M. , Baumann K.-H. , Marino G. , Mortyn P. G.
Published: June 2013

Abstract. Although ocean acidification is expected to impact (bio)calcification by decreasing the seawater carbonate ion concentration, [CO32−], there exists evidence of non-uniform response of marine calcifying plankton to low seawater [CO32−]. This raises questions on the role of environmental factors other than acidification and on the complex physiological responses behind calcification. Here we investigate the synergistic effect of multiple environmental parameters, including temperature, nutrient (nitrate and phosphate) availability, and seawater carbonate chemistry on the coccolith calcite mass of the cosmopolitan coccolithophore Emiliania huxleyi, the most abundant species in the world ocean. We use a suite of surface (late Holocene) sediment samples from the South Atlantic and southwestern Indian Ocean taken from depths lying well above the modern lysocline. The coccolith calcite mass in our results presents a latitudinal distribution pattern that mimics the main oceanographic features, thereby pointing to the potential importance of phosphorus and temperature in determining coccolith mass by affecting primary calcification and possibly driving the E. huxleyi morphotype distribution. This evidence does not necessarily argue against the potentially important role of the rapidly changing seawater carbonate chemistry in the future, when unabated fossil fuel burning will likely perturb ocean chemistry beyond a critical point. Rather our study highlights the importance of evaluating the combined effect of several environmental stressors on calcifying organisms to project their physiological response(s) in a high CO2 world and improve interpretation of paleorecords.
Mesospheric CO above Troll station, Antarctica observed by a ground based microwave radiometer
Authors: Straub C. , Espy P. J. , Hibbins R. E. , Newnham D. A.
Published: June 2013

Abstract. This paper presents mesospheric carbon monoxide (CO) data acquired by the ground-based microwave radiometer of the British Antarctic Survey (BAS radiometer) stationed at Troll station in Antarctica (72° S, 2.5° E, 1270 m a.s.l.). The dataset covers the period from February 2008 to January 2010, however, due to very low CO concentrations below approximately 80 km altitude in summer, profiles are only presented during the Antarctic winter. CO is measured for approximately 2 h each day and profiles are retrieved approximately every half hour. The retrieved profiles, covering the pressure range from 1 to 0.01 hPa (approximately 48 to 80 km), are compared to measurements from Microwave Limb Sounder on the Aura satellite (Aura/MLS) and Whole Atmosphere Community Climate Model with Specified Dynamics (SD-WACCM). This intercomparison reveals a low bias of 0.5 to 1 ppmv at 0.1 hPa (approximately 64 km) and 2.5 to 3.5 ppmv at 0.01 hPa (approximately 80 km) of the BAS microwave radiometer compared to both reference datasets. One explanation for this low bias could be the known high bias of MLS which is on the same order of magnitude. The ground based radiometer shows high and significant correlation (coefficients higher than 0.9/0.7 compared to MLS/SD-WACCM) at all altitudes compared with both reference datasets. The dataset can be accessed under http://dx.doi.org/10/mhq.
The surface temperatures of the earth: steps towards integrated understanding of variability and change
Authors: Merchant C. J. , Matthiesen S. , Rayner N. A. , Remedios J. J. , Jones P. D. , Olesen F. , Trewin B. , Thorne P. W. , Auchmann R. , Corlett G. K. , Guillevic P. C. , Hulley G. C.
Published: June 2013

Abstract. Surface temperature is a key aspect of weather and climate, but the term may refer to different quantities that play interconnected roles and are observed by different means. In a community-based activity in June 2012, the EarthTemp Network brought together 55 researchers from five continents to improve the interaction between scientific communities who focus on surface temperature in particular domains, to exploit the strengths of different observing systems and to better meet the needs of different communities. The workshop identified key needs for progress towards meeting scientific and societal requirements for surface temperature understanding and information which are presented in this community paper. A "whole-Earth" perspective is required with more integrated, collaborative approaches to observing and understanding Earth's various surface temperatures. It is necessary to build understanding of the relationships between different surface temperatures, where presently inadequate, and undertake large-scale systematic intercomparisons. Datasets need to be easier to obtain and exploit for a wide constituency of users, with the differences and complementarities communicated in readily understood terms, and realistic and consistent uncertainty information provided. Steps were also recommended to curate and make available data that are presently inaccessible, develop new observing systems and build capacities to accelerate progress in the accuracy and usability of surface temperature datasets.