bluuebunny/crossref_metadata_2025 huggingface dataset:
Vinyl sulfone silica: application of an open preactivated support to the study of transnitrosylation of plant proteins by S-nitrosoglutathione
Authors: Begara-Morales Juan C , López-Jaramillo F Javier , Sánchez-Calvo Beatriz , Carreras Alfonso , Ortega-Muñoz Mariano , Santoyo-González Francisco , Corpas Francisco J , Barroso Juan B
Published: April 2013

Background

S-nitrosylaton is implicated in the regulation of numerous signaling pathways with a diversity of regulatory roles. The high lability of the S-NO bond makes the study of proteins regulated by S-nitrosylation/denitrosylation a challenging task and most studies have focused on already S-nitrosylated proteins. We hypothesize that: i) S-nitrosoglutathione (GSNO) transnitrosylation is a feasible mechanism to account for the physiological S-nitrosylation of rather electropositive sulfur atoms from proteins, ii) affinity chromatography is a suitable approach to isolate proteins that are prone to undergo S-transnitrosylation and iii) vinyl sulfone silica is a suitable chromatographic bead.

Results

The combination of vinyl sulfone silica with GSNO yielded an affinity resin that withstood high ionic strength without shrinking or deforming and that it was suitable to isolate potential GSNO transnitrosylation target candidates. Fractions eluted at 1500 mM NaCl resulted in a symmetrical peak for both, protein and S-nitrosothiols, supporting the idea of transnitrosylation by GSNO as a selective process that involves strong and specific interactions with the target protein. Proteomic analysis led to the identification of 22 physiological significant enzymes that differ with the tissue analyzed, being regulatory proteins the most abundant group in hypocotyls. The identification of chloroplastidic FBPase, proteasome, GTP-binding protein, heat shock Hsp70, syntaxin, catalase I, thioredoxin peroxidase and cytochrome P450 that have already been reported as S-nitrosylated by other techniques can be considered as internal positive controls that validate our experimental approach. An additional validation was provided by the prediction of the S-nitrosylation sites in 19 of the GSNO transnitrosylation target candidates.

Conclusions

Vinyl sulfone silica is an open immobilization support that can be turnedad hocand in a straightforward manner into an affinity resin. Its potential in omic sciences was successfully put to test in the context of the analysis of post-translational modification by S-nitrosylation with two different tissues: mature pea leaves and embryogenic sunflower hypocotyls. The identified proteins reveal an intriguing overlap among S-nitrosylation and both tyrosine nitration and thioredoxin regulation. Chloroplastidic FBPase is a paradigm of such overlap of post-translational modifications since it is reversible modified by thioredoxin and S-nitrosylation and irreversibly by tyrosine nitration. Our results suggest a complex interrelation among different modulation mechanisms mediated by NO-derived molecules.
Brucella abortus induces TNF-α-dependent astroglial MMP-9 secretion through mitogen-activated protein kinases
Authors: Miraglia M Cruz , Scian Romina , Samartino Clara García , Barrionuevo Paula , Rodriguez Ana M , Ibañez Andrés E , Coria Lorena M , Velásquez Lis N , Baldi Pablo C , Cassataro Juliana , Delpino M Victoria , Giambartolomei Guillermo H
Published: April 2013

Background

Central nervous system (CNS) invasion by bacteria of the genus Brucella results in an inflammatory disorder called neurobrucellosis. We have recently demonstrated that B. abortus infects microglia and astrocytes, eliciting the production of a variety of pro-inflammatory cytokines which contribute to CNS damage. Matrix metalloproteinases (MMP) have been implicated in inflammatory tissue destruction in a range of pathological situations in the CNS. Increased MMP secretion is induced by pro-inflammatory cytokines in a variety of CNS diseases characterized by tissue-destructive pathology.

Methods

In this study, the molecular mechanisms that regulate MMP secretion from Brucella-infected astrocytes in vitro were investigated. MMP-9 was evaluated in culture supernatants by ELISA, zymography and gelatinolytic activity. Involvement of mitogen-activated protein kinases (MAPK) signaling pathways was evaluated by Western blot and using specific inhibitors. The role of TNF-α was evaluated by ELISA and by assays with neutralizing antibodies.

Results

B. abortus infection induced the secretion of MMP-9 from murine astrocytes in a dose-dependent fashion. The phenomenon was independent of bacterial viability and was recapitulated by L-Omp19, a B. abortus lipoprotein model, but not its LPS. B. abortus and L-Omp19 readily activated p38 and Erk1/2 MAPK, thus enlisting these pathways among the kinase pathways that the bacteria may address as they invade astrocytes. Inhibition of p38 or Erk1/2 significantly diminished MMP-9 secretion, and totally abrogated production of this MMP when both MAPK pathways were inhibited simultaneously. A concomitant abrogation of B. abortus- and L-Omp19-induced TNF-α production was observed when p38 and Erk1/2 pathways were inhibited, indicating that TNF-α could be implicated in MMP-9 secretion. MMP-9 secretion induced by B. abortus or L-Omp19 was completely abrogated when experiments were conducted in the presence of a TNF-α neutralizing antibody. MMP-9 activity was detected in cerebrospinal fluid (CSF) samples from patients suffering from neurobrucellosis.

Conclusions

Our results indicate that the inflammatory response elicited by B. abortus in astrocytes would lead to the production of MMP-9 and that MAPK may play a role in this phenomenon. MAPK inhibition may thus be considered as a strategy to control inflammation and CNS damage in neurobrucellosis.
A metabolite-centric view on flux distributions in genome-scale metabolic models
Authors: Riemer S Alexander , Rex René , Schomburg Dietmar
Published: April 2013

Background

Genome-scale metabolic models are important tools in systems biology. They permit the in-silico prediction of cellular phenotypes via mathematical optimisation procedures, most importantly flux balance analysis. Current studies on metabolic models mostly consider reaction fluxes in isolation. Based on a recently proposed metabolite-centric approach, we here describe a set of methods that enable the analysis and interpretation of flux distributions in an integrated metabolite-centric view. We demonstrate how this framework can be used for the refinement of genome-scale metabolic models.

Results

We applied the metabolite-centric view developed here to the most recent metabolic reconstruction of Escherichia coli. By compiling the balance sheets of a small number of currency metabolites, we were able to fully characterise the energy metabolism as predicted by the model and to identify a possibility for model refinement in NADPH metabolism. Selected branch points were examined in detail in order to demonstrate how a metabolite-centric view allows identifying functional roles of metabolites. Fructose 6-phosphate aldolase and the sedoheptulose bisphosphate bypass were identified as enzymatic reactions that can carry high fluxes in the model but are unlikely to exhibit significant activity in vivo. Performing a metabolite essentiality analysis, unconstrained import and export of iron ions could be identified as potentially problematic for the quality of model predictions.

Conclusions

The system-wide analysis of split ratios and branch points allows a much deeper insight into the metabolic network than reaction-centric analyses. Extending an earlier metabolite-centric approach, the methods introduced here establish an integrated metabolite-centric framework for the interpretation of flux distributions in genome-scale metabolic networks that can complement the classical reaction-centric framework. Analysing fluxes and their metabolic context simultaneously opens the door to systems biological interpretations that are not apparent from isolated reaction fluxes. Particularly powerful demonstrations of this are the analyses of the complete metabolic contexts of energy metabolism and the folate-dependent one-carbon pool presented in this work. Finally, a metabolite-centric view on flux distributions can guide the refinement of metabolic reconstructions for specific growth scenarios.
Taper design for block processing of seismic data
Authors: Bekara Maïza
Published: April 2013

In many seismic processing applications, such as filtering and interpolation, the input data is partitioned into small overlapping blocks that are processed separately and then merged to construct the final output data. Tapering the different blocks before merging is done to account for the overlap and to avoid visible artefacts related to the imprint of the blocking. While tapering is important, the design of blocking tapers is often done in a simplistic way. I propose a method to design any [Formula: see text]-dimension blocking taper with any amount of overlap. The proposed taper has the property that its aggregate sum across the data section is one, thus fold computation and normalization is avoided. In addition, the taper has some useful spectral features so it can also be used as a pre-Fourier transformation taper when the processing involves such transformation.
Cost-effectiveness of depression case management in small practices
Authors: Gensichen Jochen , Petersen Juliana J. , Von Korff Michael , Heider Dirk , Baron Steffen , König Jochem , Freytag Antje , Krauth Christian , Gerlach Ferdinand M. , König Hans-Helmut
Published: April 2013

Background

Case management undertaken by healthcare assistants in small primary care practices is effective in improving depression symptoms and adherence in patients with major depression.

Aims

To evaluate the cost-effectiveness of depression case management by healthcare assistants in small primary care practices.

Method

Cost-effectiveness analysis on the basis of a pragmatic randomised controlled trial (2005-2008): practice-based healthcare assistants in 74 practices provided case management to 562 patients with major depression over 1 year. Our primary outcome was the incremental costeffectiveness ratio (ICER) calculated as the ratio of differences in mean costs and mean number of qualityadjusted life-years (QALYs). Our secondary outcome was the mean depression-free days (DFDs) between the intervention and control group at 24-month follow-up. The study was registered at the International Standard Randomised Controlled Trial Number Registry: ISRCTN66386086.

Results

Intervention v. control group: no significant difference in QALYs; significantly more DFDs (mean: 373 v. 311,P<0.01); no significant difference in mean direct healthcare costs (€4495 v. €3506, P = 0.16); considerably lower mean indirect costs (€5228 v. €7539, P = 0.06), resulting in lower total costs (€9723 v. €11 045, P = 0.41). The point estimate for the cost-utility ratio was €38 429 per QALY gained if only direct costs were considered, and ‘dominance’ of the intervention if total costs were considered. Yet, regardless of decision makers' willingness to pay per QALY, the probability of the intervention being cost-effective was never above 90%.

Conclusions

In small primary care practices, 1 year of case management did not increase the number of QALYs but it did increase the number of DFDs. The intervention was likely to be cost-effective.
Power output of skinned skeletal muscle fibres from the cheetah (Acinonyx jubatus)
Authors: West Timothy G. , Toepfer Christopher N. , Woledge Roger C. , Curtin Nancy A. , Rowlerson Anthea , Kalakoutis Michaeljohn , Hudson Penny , Wilson Alan M.
Published: April 2013

Muscle samples were taken from the gluteus, semitendinosus and longissimus muscles of a captive cheetah immediately after euthanasia. Fibres were "skinned" to remove all membranes leaving the contractile filament array intact and functional. Segments of skinned fibres from these cheetah muscles and from rabbit psoas muscle were activated at 20°C by a temperature jump protocol. Step and ramp length changes were imposed after active stress had developed. The stiffness of the non-contractile ends of the fibres (series elastic component) was measured at two different stress values in each fibre; stiffness was strongly dependent on stress. Using these stiffness values, the speed of shortening of the contractile component was evaluated, and hence the power it was producing. Fibres were analysed for myosin heavy chain content using gel electrophoresis, and identified as either slow (Type I) or fast (Type II). The power output of cheetah Type II fibre segments was 92.5 ± 4.3 W kg-1 (mean ±s.e., 14 fibres) during shortening at relative stress 0.15 (=stress during shortening/isometric stress). For rabbit psoas fibre segments (presumably Type IIX) the corresponding value was significantly higher (P<0.001), 119.7 ± 6.2 W kg-1 (mean ±s.e.,7 fibres). These values are our best estimates of the maximum power output under the conditions used here. Thus the contractile filament power from cheetah was less than that of rabbit when maximally activated at 20°C, and does not account for the superior locomotor performance of the cheetah.
New methods for field collection of human skin volatiles and perspectives for their application in the chemical ecology of human/pathogen/vector interactions
Authors: Dormont Laurent , Bessière Jean-Marie , McKey Doyle , Cohuet Anna
Published: April 2013

Odours emitted by human skin are of great interest to biologists in many fields, with practical applications in forensics, health diagnostic tools and the ecology of blood-sucking insect vectors of human disease. Convenient methods are required for sampling human skin volatiles under field conditions. We experimentally compared four modern methods for sampling skin odours: solvent extraction, headspace SPME, and two new techniques not previously used for the study of mammal volatiles, contact SPME and dynamic headspace with a Chromatoprobe design. These methods were tested and compared both on European subjects under laboratory conditions, and on young African subjects under field conditions. All four methods permitted effective trapping of skin odours, including the major known human skin volatile compounds. In both laboratory and field experiments, contact SPME, in which the time of collection was restricted to 3 minutes, provided results very similar to those obtained with classical headspace SPME, a method that requires 45 minutes of collection. Chromatoprobe sampling also proved to be very sensitive, rapid, and convenient for the collection of human-produced volatiles in natural settings. Both these two new techniques, contact SPME and Chromatoprobe design, may considerably facilitate the study of human skin volatiles under field conditions, opening new possibilities for examining the olfactory cues mediating the host-seeking behaviour of mosquito vectors implicated in transmission of major diseases.
Construction of a Synchrotron-Radiation Vacuum-Ultraviolet Circular-Dichroism Spectrophotometer and Its Application to the Structural Analysis of Biomolecules
Authors: Matsuo Koichi , Gekko Kunihiko
Published: April 2013

A vacuum-ultraviolet (VUV) circular-dichroism (CD) spectrophotometer usable down to 140 nm was constructed using synchrotron radiation and applied to the structural analyses of various saccharides, amino acids, and proteins in aqueous solutions. Most monosaccharides and disaccharides exhibited a positive CD peak around 170 nm, depending on anomeric and axial/equatorial configurations of hydroxy groups, trans–gauche configurations of hydroxymethyl groups, and the type of glycosidic linkage. The VUVCD spectra of glycosaminoglycans sensitively reflected the characteristic contributions of constituent functional groups in the VUV region. l-Isomers of amino acids showed two successive positive peaks around 200 and 180 nm, depending on the types of side chains. The VUVCD spectrum of alanine theoretically calculated using a time-dependent density functional theory revealed the important role of hydration for stabilizing the alanine structure. The VUVCD spectra of native proteins down to 160 nm improved the predictive accuracy for the contents, numbers of segments, and sequences of α-helices and β-strands. These secondary-structure analyses were also successfully applied to various types of nonnative proteins. The obtained results demonstrate that synchrotron-radiation VUVCD spectroscopy is a powerful technique for the structural analysis of biomolecules in aqueous solution, and hence could open a new field in structural biology.
Functional patterns of thumb key pinch and their influence on thumb strength and stability
Authors: Punsola-Izard Vicenç , Salas-Gómez Diana , Sirvent-Rivalda Enric , Esquirol-Caussà Jordi
Published: April 2013

Introduction

Trapeziometacarpal osteoarthritis (TMC OA) is a common condition frequently related to instability and hypermobility. Many factors are involved in the development of this degenerative process. Recent research suggests that the position of the metacarpophalangeal (MCP) joint may influence TMC joint contact wear patterns and subsequent development of OA. The aim of this study is to explore the alignment of the MCP joint of the thumb during lateral pinch in order to describe the naturally occurring alignment in a group of healthy volunteers without symptoms.

Methods

One hundred and nine participants were asked to apply a lateral pinch manoeuvre to a pinchmeter, while their thumbs were assessed. Passive hypermobility of the thumb MCP (MCP) joint was assessed, key pinch strength was measured, key pinch position was photographed and the angle of the joints during the assessment was measured.

Results

Four different functional pinch patterns were identified. The most frequent pattern seems to be MCP hyperextension described by Moulton as harmful for the TMC joint. The level of strength obtained did not correspond to the pinch pattern used, and hypermobility of the thumb MCP joint did not determine the position of the thumb during key pinch.

Conclusion

Four different thumb postures were identified during lateral pinch; however, these postures were not associated with any difference in pinch strength. We conclude that the more unstable and mechanically inefficient postures are compensated by functional capacity.
Requesting radiological investigations – do junior doctors know their patients? A cross-sectional survey
Authors: Bosanquet Dc , Cho Js , Williams N , Gower D , Thomas K Gower , Lewis Mh
Published: April 2013

Summary

Objectives

To ascertain clinicians’ knowledge of their patients when requesting radiological investigations, as required legally by UK government legislation ‘Ionising Radiation (Medical Exposure) Regulations 2000’ (IRMER 2000), following the implementation of European Working Time Directive.

Design

Cross sectional survey.

Participants

All doctors requesting radiological requests every Monday, following the weekend on-call, over an 8-week period. There were no exclusion criteria.

Main outcome measures

Baseline data analysis, including grade and specialty of requesting doctor, types of modality requested, knowledge of their patient, addressograph signature confirming identity and appropriateness of investigation.

Results

164 requests were received, the majority (61%) were made by Foundation Programme 1 (FP1) doctors and general medical specialties accounted for the highest proportion of requests (45%). Ultrasound scanning was the most frequently requested investigation (47%), closely followed by computed tomography (CT) scans (42%). Almost a third (30%) of requests were made by doctors who had not seen the patient to be investigated, predominantly by FP1 doctors (p=0.003) and more frequently by general medical specialties (p=0.001). Signatures were absent on 20% of the addressographs and overall, 10% of requests were deemed inappropriate.

Conclusions

In almost a third of radiological requests, doctors have not seen patients to be investigated, most likely as a result of shift working patterns. This does not fulfil the IRMER 2000 criteria and potentially exposes patients to unnecessary and inappropriate radiation.
All-fiber Q-switched and cavity dumped laser using an electrically addressed microstructured fiber
Authors: Malmström Mikael , Margulis Walter , Yu Zhangwei , Tarasenko Oleksander , Laurell Fredrik
Published: April 2013

We report on a pulsed fiber laser with two regimes of operation, one where cavity-roundtrip pulse durations are produced (85 ns long, 40 Wpp) and one with high power pulses (2 ns long, 148 Wpp).
Curved Focal Plane Arrays: Advantages and Fabrication Using a MEMS Post-Process
Authors: Peumans Peter
Published: April 2013

Article not available.
Resolution Limits in Digital Photography: the Looming End of the Pixel Wars
Authors: Baer Richard L.
Published: April 2013

Diffraction and motion blur limit impose limits on pixel size and therefore on digital camera resolution. Photographic utility is actually a better metric for camera comparisons than resolution.
LIBS on Silicon Oxide and Nitride Thin Films
Authors: Akpovo Charlemagne , Barnett Cleon , Brown Staci , Johnson Lewis
Published: April 2013

Laser induced breakdown spectroscopy (LIBS) has often been employed in the detection of energetic and other trace material. However, issues with uniform trace material deposition has not been fully understood so as to produce reference samples. In this work, LIBS is used to quantify the amount of oxygen, nitrogen rich material that can be ablated from uniform thin films of various thicknesses deposited on silicon substrate. Both single and double pulse LIBS were employed to study the amount of material removal and percent ionization as a function of trace and bulk material, in ambient atmosphere.
Detailed Terrain Characterization from a Space Based Imaging Spectrometer
Authors: Cooley Thomas
Published: April 2013

Imaging spectrometers have been developed and matured over the past 30 years beginning with developmental airborne systems. Beginning with the NASA Hyperion instrument, space borne systems are providing data to a broad user community to explore the myriad applications of spaceborne imaging spectrometer data. This presentation will explore the range of terrain characterization applications and products which are being addressed currently and those that could be met in the future as sensors are improved and tailored to the user needs.
Acceptance Angle and Illumination Uniformity for Overfilled Optical Concentrators
Authors: Kost Alan R. , Liu Katherine X. , Qian Charles X.
Published: April 2013

Solar concentrators are frequently characterized by an acceptance angle that specifies optical throughput when the concentrator is misaligned. Here we introduce an effective acceptance angle that includes the effect of illumination non-uniformity on system performance.
Effect of Sustained Typing Work on Changes in Scapular Position, Pressure Pain Sensitivity and Upper Trapezius Activity
Authors: Park Se‐Yeon , Yoo Won‐Gyu
Published: April 2013

Effect of Sustained Typing Work on Changes in Scapular Position, Pressure Pain Sensitivity and Upper Trapezius Activity: Se‐Yeon PARK, et al. Department of Physical Therapy, The Graduate School, Inje University, Republic of Korea—

Objective

The aim of this study was to investigate the effects of sustained computer keyboard typing on the human musculoskeletal system by assessing the pressure‐pain threshold (PPT), scapular position and activation of the upper trapezius.

Methods

Vertical and horizontal positional changes of the scapular were measured with a palpation meter before and after keyboard work, and the PPT was measured using a pressure algometer. Activation of the upper trapezius during 20 minutes of computer keyboard work was measured by electromyography, and four consecutive 5‐minute segments were analyzed.

Results

The vertical distance from the seventh cervical process to the acromion, and the horizontal distance from the inferior angle to the same level of the spinal process were significantly increased after keyboard typing work compared with before keyboard typing work (p<0.05). The average value of the upper trapezius activity increased with increased time at the keyboard. The percent reference voluntary contraction of phase 1 (from start to 5 minutes) was lower than those of phase 2 (from 5 to 10 minutes), and phase 3 (from 10 to 15 minutes) (p<0.05).

Conclusions

We observed that sustained computer work changed the scapular position in the stretched upper trapezius. To prevent musculoskeletal problems in the shoulder region, posture reeducation during computer work should be considered in terms not only of neck and trunk posture, but also of scapular position.
Interim Performance Measures and Private Information
Authors: Hofmann Christian , Rothenberg Naomi R.
Published: April 2013

This study investigates whether having an upstream or downstream agent privately observe an interim performance measure and disseminating this measure to the other agent is valuable to the principal. The signal is informative about the upstream agent's action and positively correlated with output. If the upstream agent privately observes the signal, then there can be a higher cost of the downstream agent if the signal is sufficiently forward-looking. If the downstream agent privately observes the signal, then the trade-off involves rents to the downstream agent versus a reduced cost for the upstream agent. Private observation of an interim signal is valuable to the principal if it is not too forward-looking. The choice between upstream and downstream agent depends nontrivially on the signal's backward-looking quality. The results suggest that the value of observation and dissemination of an interim signal depends on the informativeness of output and the signal about upstream and downstream production.

JEL Classifications: D82, D83, L20, M40.
Delayed intracranial hypertension after cranial vault remodeling for nonsyndromic single-suture synostosis
Authors: Cetas Justin S. , Nasseri Morad , Saedi Targol , Kuang Anna A. , Selden Nathan R.
Published: April 2013

Object

Delayed intracranial hypertension may occur after cranial vault remodeling for synostosis and may result in visual loss and developmental delay. Delayed intracranial hypertension is relatively common in children with syndromic, multisuture synostosis, but the incidence is poorly defined in children with single-suture nonsyndromic synostosis. This study evaluates the frequency of reoperation for delayed intracranial hypertension after single-suture synostosis repair.

Methods

Patients who had undergone cranial vault remodeling for nonsyndromic single-suture synostosis and were treated at a single tertiary pediatric hospital between July 2000 and December 2010 were analyzed for the occurrence of delayed intracranial hypertension and reoperation for cranial vault remodeling.

Results

Eighty-one patients with clinical follow-up of at least 3 years were analyzed from a total of 156 consecutive patients. The average patient age at the initial operation was 9.1 months. Five (6.2%) of 81 patients presented with delayed clinical and ophthalmological signs and symptoms of intracranial hypertension following initial cranial vault reconstruction, confirmed indirectly in each case by CT findings and directly by intracranial pressure monitoring. These 5 patients underwent repeat cranial vault reconstruction.

Conclusions

Calvarial growth restriction and intracranial hypertension occur sporadically following primary cranial vault reconstruction for single-suture nonsyndromic cranial synostosis. In this series, delayed intracranial hypertension occurred only in male patients who underwent primary repair of isolated sagittal synostoses at an age less than or equal to 5 months.
“The play’s the thing”: theatre as a scholarly meeting ground in age studies
Authors: Barnes Lipscomb Valerie
Published: April 2013

Addressing three current critical turns in gerontology, this article proposes the theatre as a fertile ground for various theoretical angles in age studies - including the performative on and off stage, the narrative in the script and the critical questioning of age and ageism in the multiple realities of performance. Beginning from a shared site in the theatre, researchers may be able to establish greater common ground, resulting not only in multi-disciplinary efforts but also in truly interdisciplinary work. With a foundation in performance studies, this article suggests promising directions for age studies and theatre scholarship by examining three aspects of theatrical production: a play script, Jan de Hartog’s popular The Fourposter (1951); a collaborative development of a script and production, Jeanette Mathewes Stevens’ 2010 senior drama ElderSpeak; and a performance, a 2011 song-and-dance revue staged by an established senior theatre troupe, the Sarasota Senior Theater.
Impact of High Salt Independent of Blood Pressure on PRMT/ADMA/DDAH Pathway in the Aorta of Dahl Salt-Sensitive Rats
Authors: Cao Yu , Mu Jian-Jun , Fang Yuan , Yuan Zu-Yi , Liu Fu-Qiang
Published: April 2013

Endothelial dysfunction participates in the development and progression of salt-sensitive hypertension. Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide synthase (NOS). The objectives of this study were to investigate the impact of a high salt diet on the PRMT/ADMA/DDAH (protein arginine methyltransferases; dimethylarginine dimethylaminohydrolase) pathway in Dahl salt-sensitive (DS) rats and SS-13BN consomic (DR) rats, and to explore the mechanisms that regulate ADMA metabolism independent of blood pressure reduction. Plasma levels of nitric oxide (NO) in DS rats given a high salt diet and subjected to intragastric administration of hydralazine (SH + HYD group) were lower than those given a normal salt diet (SN group). There were significant decreases in expression and activity of dimethylarginine dimethylaminohydrolase (DDAH) and endothelial NO synthase (eNOS) in DS rats given a high diet (SH group) in comparison to the SN group. The activity of DDAH and expression of eNOS in the SH + HYD group decreased more significantly than SN group. The mRNA expression of DDAH-1 and DDAH-2 were lowest in the SH group. The results suggest that salt, independent of blood pressure, can affect the PRMT-1/ADMA/DDAH system to a certain degree and lead to endothelial dysfunction in Dahl salt-sensitive rats.
Randomness and Statistical Laws of Indentation-Induced Pop-Out in Single Crystal Silicon
Authors: Huang Hu , Zhao Hongwei , Shi Chengli , Zhang Lin , Wan Shunguang , Geng Chunyang
Published: April 2013

Randomness and discreteness for appearance of pop-out of the single crystal silicon with a (100) orientation were studied by a self-made indentation device. For a given maximum penetration load, the load Ppo for appearance of pop-out fluctuates in a relatively large range, which makes it hard to study the effect of the loading/unloading rate on the load Ppo. Experimental results with different maximum penetration loads indicate that the critical penetration load for appearance of pop-out is in the range of 15 mN~20 mN for the current used single crystal silicon. For a given maximum penetration load, the load Ppo for appearance of pop-out seems random and discrete, but in the point of statistics, it has an obviously increasing trend with increase of the maximum penetration load and also the fraction Ppo/Pmax approximately keeps in the range of 0.2~0.5 for different maximum penetration loads changing from 15 mN to 150 mN.
Analysis and Description of HOLTIN Service Provision for AECG monitoring in Complex Indoor Environments
Authors: Led Santiago , Azpilicueta Leire , Aguirre Erik , De Espronceda Miguel , Serrano Luis , Falcone Francisco
Published: April 2013

In this work, a novel ambulatory ECG monitoring device developed in-house called HOLTIN is analyzed when operating in complex indoor scenarios. The HOLTIN system is described, from the technological platform level to its functional model. In addition, by using in-house 3D ray launching simulation code, the wireless channel behavior, which enables ubiquitous operation, is performed. The effect of human body presence is taken into account by a novel simplified model embedded within the 3D Ray Launching code. Simulation as well as measurement results are presented, showing good agreement. These results may aid in the adequate deployment of this novel device to automate conventional medical processes, increasing the coverage radius and optimizing energy consumption.
The analysis of size-segregated cloud condensation nuclei counter (CCNC) data and its implications for aerosol-cloud interactions
Authors: Paramonov M. , Aalto P. P. , Asmi A. , Prisle N. , Kerminen V.-M. , Kulmala M. , Petäjä T.
Published: April 2013

Abstract. Ambient aerosol, CCN and hygroscopic properties were measured with a size-segregated CCNC in a~boreal environment of Southern Finland at the SMEAR II station. The instrumental setup operated at five levels of supersaturation S covering a range from 0.1 to 1% and measured particles with a size range of 20–300 nm; a total of 29 non-consecutive months of data are presented. The median critical diameter Dc ranged from 150 nm at S of 0.1% to 46 nm at S of 1.0%. The median aerosol hygroscopicity parameter κ ranged from 0.41 at S of 0.1% to 0.14 at S of 1.0%, indicating that ambient aerosol in Hyytiälä is less hygroscopic than the global continental or European continental averages. It is, however, more hygroscopic than the ambient aerosol in an Amazon rainforest, a European high alpine site or a forested mountainous site. A fairly low hygroscopicity in Hyytiälä is likely a result of a large organic fraction present in the aerosol mass comparative to other locations within Europe. A considerable difference in particle hygroscopicity was found between particles smaller and larger than ~100 nm in diameter, possibly pointing out to the effect of cloud processing increasing κ of particles > 100 nm in diameter. The hygroscopicity of the smaller, ~50 nm particles did not change seasonally, whereas particles with a diameter of ~150 nm showed a decreased hygroscopicity in the summer, likely resulting from the increased VOC emissions of the surrounding boreal forest and secondary organic aerosol (SOA) formation. For the most part, no diurnal patterns of aerosol hygroscopic properties were found. Exceptions to this were the weak diurnal patterns of small, ~50 nm particles in the spring and summer, when a peak in hygroscopicity around noon was observed. No difference in CCN activation and hygroscopic properties was found on days with or without atmospheric new particle formation. During all seasons, except summer, a CCN-inactive fraction was found to be present, rendering the aerosol of 75–300 nm in diameter as internally mixed in the summer and not internally mixed for the rest of the year.
Influence of aerosol lifetime on the interpretation of nucleation experiments with respect to the first nucleation theorem
Authors: Ehrhart S. , Curtius J.
Published: April 2013

Abstract. The SAWNUC microphysical aerosol nucleation model is used to study the effect of reactor walls on the interpretation of nucleation experiments with respect to nucleation theory. This work shows that loss processes, such as wall losses, influence the interpretation of nucleation experiments, especially at low growth rates and short lifetime of freshly nucleated particles. In these cases the power dependency of the formation rates, determined at a certain particle size, with respect to H2SO4 does not correspond to the approximate number of H2SO4 molecules in the critical cluster as expected by the first nucleation theorem. Observed ∂log(J)/∂log([H2SO4]) therefore can vary widely for identical nucleation conditions but different sink terms.
Retrieval of nitric oxide in the mesosphere and lower thermosphere with SCIAMACHY
Authors: Bender S. , Sinnhuber M. , Burrows J. P. , Langowski M. , Funke B. , López-Puertas M.
Published: April 2013

Abstract. We use the ultra-violett (UV) spectra in the range 230–300 nm from the SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY) to retrieve the nitric oxide (NO) number densities from atmospheric emissions in the gamma-bands in the mesosphere and lower thermosphere. Using 3-D ray tracing, a 2-D retrieval grid, and regularisation with respect to altitude and latitude, we retrieve a whole semi-orbit simultaneously for the altitude range from 60 to 160 km. We present details of the retrieval algorithm, first results, and initial comparisons to data from the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS). Our results agree on average well with MIPAS data and are compatible with previously published measurements from other instruments. For the time of available measurements in 2008–2011, we achieve a vertical resolution of 5–10 km in the altitude range 70–140 km and a horizontal resolution of about 9° from 60° S–60° N. With this we have independent measurements of the NO densities in the mesosphere and lower thermosphere with approximately global coverage.
From observation to the quantification of snow processes with a time-lapse camera network
Authors: Garvelmann J. , Pohl S. , Weiler M.
Published: April 2013

Abstract. A network of 45 spatially distributed time-lapse cameras was used to carry out a continuous observation of snow processes and snow cover properties throughout three mid-latitude medium elevation mountain catchments in hourly intervals during the winter seasons of 2010/2011 and 2011/2012. A simple technical modification was conducted to enable the deployment of the standard digital cameras in any location. Image analysis software was applied to extract information about snow depth, surface albedo and canopy interception from the digital images. Furthermore, the distributed design of the camera network made it possible to identify the elevation of the snow rain interface for any precipitation event which is very helpful for the interpretation of winter flooding events resulting from snow melt. Exemplary data for all these analyses is presented to show the potential fields of application of this innovative approach. Study results prove that the application of digital time-lapse photography is an appropriate technique to observe the spatial distribution and temporal evolution of seasonal snow covers in a mountainous environment.
Analysis of the Economic Impact of Meteorological Disasters on Tourism: The Case of Typhoon Morakot's Impact on the Maolin National Scenic Area in Taiwan
Authors: Liu Tzu-Ming
Published: April 2013

This study explores the cost of extreme weather disasters to the tourism industry, taking the Taiwan Maolin National Scenic Area as an example. The paper evaluates the economic damage caused by typhoon Morakot. The author uses long-term tourist trend lines as the basis for calculating disaster losses and adopts an error correction model as a measurement method for the estimation. The study finds that the entire park lost over 700,000 visitors in the year and a half after the disaster, representing a loss of NT$1.39 billion in tourism business – a value three times the infrastructure loss. Any delays in reconstruction will increase the losses to the tourism industry. However, several tourist spots were gradually losing their attractiveness even before the disaster, and hastening to rebuild such sites is not conducive to the recovery of tourism. Rather, efforts should first be made to understand the reasons why these tourist spots were becoming less attractive and to gauge tourist demand for them before their reconstruction.
International Tourists' Decision Timing: Cross-National Differences
Authors: Thrane Christer , Farstad Eivind , Dybedal Petter
Published: April 2013

This study concerns decision timing in international tourism; that is, the amount of time that elapses between a decision being made to visit a foreign country and the trip actually taking place. In particular, the focus is on differences in decision times among tourists of different nationalities. The empirical setting is the inbound summer tourism market in Norway, and the data are based on a large-scale visitor survey conducted in 2011. The average international tourist visiting Norway during the 2011 summer season made the decision to do so about six months in advance; however, there were noticeable national differences in this regard. Furthermore, the results show that certain other independent variables contribute to the statistical explanation of variations in decision times. The implications for further research and marketing are discussed.
Measuring and Analysing Domestic Tourism: The Importance of an Origin and Destination Matrix
Authors: Gálvez Teresa Guardia , Romero Juan Muro , Devesa María Jesús Such
Published: April 2013

In this study, using the Spanish domestic and outbound tourism survey FAMILITUR, an inter-regional tourism flows analysis is carried out for the period 2004–2008. The degree of concentration of origin–destination trips is calculated in order to obtain the market share of the distribution of regional trips. An intra-regional perspective is also presented to confirm other divergences in terms of the region's capacity of attraction for its own residents. Finally, a ‘gravity’ model of domestic travel flows between the 17 Spanish autonomous communities is estimated to characterize the variables that affect Spaniards' tourism flows.
Territory Impact on the Performance of Spanish Vacation Hotels
Authors: Marco-Lajara Bartolomé , Úbeda-García Mercedes , Sabater-Sempere Vicente , García-Lillo Francisco
Published: April 2013

Although Spain is among the world's most visited tourist destinations, not all Spanish regions receive the same flow or number of tourists, and the type of visitor varies from one region to another. This paper analyses the structure of the tourism industry across the six most important tourist regions in Spain. Its main aim is to identify the most relevant factors for each of these regions, explaining the differences between them not only in terms of the number of tourists they receive but also in terms of tourist behaviour. The authors select two theoretical models empirically validated in previous studies: Porter's Diamond model, which helps to explain why the tourism industry is more competitive in some Spanish regions than in others, and the theory of tourist districts, which clarifies why the tourism industry tends to develop in very specific geographical areas.
Circumnutation in the growth of Chara rhizoids
Authors: Bełtowski Marek
Published: April 2013

Chara rhizoids, cylindrical cells growing in their apex, having the capability of positive orthogravitropic response, while growing without any change of position are not ideally straight, but they are characterised by slight and repeating cyclic bendings. The mean distance between successive bendings is 150 µm. The bendings appear more or less every 1.5 hour at rhizoids' growth rate of about 100 µm h-1. After the displacement of the rhizoids from the vertical to the horizontal position, during the gravireaction, the curvature proceeds in stages, in which, alternatingly, there appear periods of higher or lower curvature. The curvature of successive higher bendings decreases when the rhizoid reaches the vertical direction. It seems that gravireaction is based on the increase of the maximal curvature of cyclic bendings and directing the bendings into a vertical plane. Other tip growing cells, generally straight, such as root hairs or hyphae of Mucor and Phycomyces, also show the repeating bendings.
Correlation of protein content to flatulent galactooligosaccharides and exogenous amino acids in seeds of Phaseolus vulgaris L.
Authors: Kosson Ryszard
Published: April 2013

In order to estimate the possible correlations among constituents of Phaseolus vulgaris seeds, the contents of protein, exogenous amino acids and flatulent galactooligosaccharides (raffinose and stachyose) were analyzed in 16 Polish bean cultivars for dry seeds. A negative correlation coefficient (r =-0.9490) was found between protein and methionine contents. High positive correlations among exogenous amino acids, such as lysine and isoleucine, valine and isoleucine, lysine and tyrosine, were observed indicating a chance of selecting far more than one at a time. The small-seeded bean cultivars contained higher contents of protein and galactooligosaccharides than the large-seeded ones.
Light-triggered action potentials in plants
Authors: Trębacz Kazimierz
Published: April 2013

Special attention is paid in this paper to the criteria of the light-triggered action potential, namely the all-or-none law, propagation, the occurrence of refractory periods. Such action potentials have been recorded in Acetabularia mediterranea, Asplenium trichomanes, Bryum pseudotriquetrum, Eremosphaera viridis and Concephalum conicum. In Acetabularia, action potentials are generated after sudden cessation of light stimuli of sufficient intensity. The depolarization phase of the action potential develops as a result of a transient reversal of the action of the electrogenic Cl- pump. This is a principle of the "metabolic" action potential hypothesis proposed by Gradmann. In the gametophytes of Aspleniam trichoma­nes and Bryum pseudo triquetrum, action potentials are triggered on illumination. Gutation starts 1.5-2 seconds after the passage of an action potential. The active water secretion facilitates fertilization. In the unicellular fresh water alga, Eremosphaera viridis, action potential-like responses are evoked after light termination. The process responsible for its appearance is the opening of potassium channels in the plasmalemma. The liverwort, Conocephalum conicum, generates action potentials in response to light, electrical, chemical and mechanical stimuli. Calcium and potassium channels as well as proton pumps are involved in electrogenesis of action impulses in the species. Excitation causes a significant increase in the respiration rate. The role of action impluses as mediators in a system of a metabolism control is discussed.
Problematic octaploid forms and a new chromosome number in the genus Achillea L., 2n = 126
Authors: Dąbrowska Janina
Published: April 2013

Among the offspring of a problematic form of Achillea sp., a 2n = 126 seedling which probably arose as the result of fusion of unreduced octo- and hexaploid gametes (72 + 54) was found along with seedlings having an octaploid chromosome number (2n = 72). Putative paths leading to the formation of problematic octaploid forms and plants with 126 chromosomes are discussed.