bluuebunny/crossref_metadata_2025 huggingface dataset:
Likely future extirpation of another Asian river dolphin: The critically endangered population of the Irrawaddy dolphin in the Mekong River is small and declining
Authors: Beasley I. , Pollock K. , Jefferson T. A. , Arnold P. , Morse L. , Yim S. , Lor Kim S. , Marsh H.
Published: October 2012

The population of Irrawaddy dolphins that occupies the Mekong River in southern Lao People's Democratic Republic and Cambodia is classified as Critically Endangered by the IUCN. Based on capture‐recapture of photo‐identified individuals, we estimated that the total population numbered 93 ±  SE 3.90 individuals (95% CI 86–101), as of April 2007. The combined photo‐identification and carcass recovery program undertaken from 2001 to 2007 established that the Irrawaddy dolphin population inhabiting the Mekong River has reached a critical point with regards to its continued survival, where immediate research and management actions are required to greatly reduce adult mortality, and establish the cause of newborn mortality. In addition, community consultation is required to initiate, and evaluate, urgently required conservation measures. An ongoing well‐designed combined program of abundance estimation (i.e., photo‐identification) and carcass recovery is required to monitor total population size and mortality rates, to inform and evaluate management initiatives. The conclusions of this paper are likely generic to river dolphin populations, particularly where photo‐identification is possible.
A search cost model of obfuscation
Authors: Ellison Glenn , Wolitzky Alexander
Published: October 2012

This article develops models in which obfuscation is individually rational for oligopolistic firms. Firms sell a homogeneous good to rational consumers who incur search costs to learn prices. Search costs are endogenized by allowing obfuscation—firms have an unobservable action that increases the time needed to learn their price. One model involves search costs convex in shopping time. We show that slight convexity can dramatically alter the equilibrium price distribution. A second model examines an informational linkage between current and future search costs: consumers are uncertain about a component of search costs. Here, a signal‐jamming mechanism can lead to equilibrium obfuscation.
Efficacy of Pimobendan in the Prevention of Congestive Heart Failure or Sudden Death in Doberman Pinschers with Preclinical Dilated Cardiomyopathy (The PROTECT Study)
Authors: Summerfield N.J. , Boswood A. , O'Grady M.R. , Gordon S.G. , Dukes‐McEwan J. , Oyama M.A. , Smith S. , Patteson M. , French A.T. , Culshaw G.J. , Braz‐Ruivo L. , Estrada A. , O'Sullivan M.L. , Loureiro J. , Willis R. , Watson P.
Published: October 2012

Background

The benefit of pimobendan in delaying the progression of preclinical dilated cardiomyopathy (DCM) in Dobermans is not reported.

Hypothesis

That chronic oral administration of pimobendan to Dobermans with preclinical DCM will delay the onset of CHF or sudden death and improve survival.

Animals

Seventy‐six client‐owned Dobermans recruited at 10 centers in the UK and North America.

Methods

The trial was a randomized, blinded, placebo‐controlled, parallel group multicenter study. Dogs were allocated in a 1:1 ratio to receive pimobendan (Vetmedin capsules) or visually identical placebo.

The composite primary endpoint was prospectively defined as either onset of CHF or sudden death. Time to death from all causes was a secondary endpoint.

Results

The proportion of dogs reaching the primary endpoint was not significantly different between groups (P = .1). The median time to the primary endpoint (onset of CHF or sudden death) was significantly longer in the pimobendan (718 days, IQR 441–1152 days) versus the placebo group (441 days, IQR 151–641 days) (log‐rank P = 0.0088). The median survival time was significantly longer in the pimobendan (623 days, IQR 491–1531 days) versus the placebo group (466 days, IQR 236–710 days) (log‐rank P = .034).

Conclusion and Clinical Importance

The administration of pimobendan to Dobermans with preclinical DCM prolongs the time to the onset of clinical signs and extends survival. Treatment of dogs in the preclinical phase of this common cardiovascular disorder with pimobendan can lead to improved outcome.
Craniosacral therapy: a systematic review of the clinical evidence
Authors: Ernst Edzard
Published: October 2012

Aim

Craniosacral
therapy (CST) is a popular treatment for a wide range of
conditions. This systematic review evaluates the evidence of
effectiveness for CST for any human
condition.

Method

An
electronic search for relevant studies was conducted across three
databases; this was complemented by extensive hand‐searching of
departmental files and bibliographies. Articles were included if they
reported RCTs of CST for any human condition. Data
were extracted according to predefined criteria and trial quality was
determined using the Jadad
score.

Results

Six
studies were included. Except for one, all were associated with a high
risk of bias. Low quality studies suggested positive effects, while the
high‐quality trial failed to demonstrate
effectiveness.

Conclusion

The
notion that CST is associated with more than
non‐specific effects is not based on evidence from rigorousRCTs.
Student Nurses' Perceived Use of NANDA‐I Nursing Diagnoses in the Community Setting
Authors: Ogunfowokan Adesola A. , Oluwatosin Abimbola O. , Olajubu Aanuoluwapo O. , Alao Olujide A. , Faremi Adenike F.
Published: October 2012

PURPOSE:  Study explored knowledge and perception of student nurses on the use of NANDA‐I nursing diagnoses in the community setting.

METHODS:  Study adopted cross‐sectional design. Convenient sampling method was used to select 290 nursing students. Data analysis was by descriptive and inferential statistics.

RESULTS:  A majority (81.3%) of the participants considered NANDA‐I nursing diagnoses to be useful in the community. Significant association existed in the perception and level of education of the students (χ2= 8.257, d.f. = 1, p= .04).

CONCLUSIONS:  Knowledge and perception of the participants about the use of NANDA‐I nursing diagnoses in the community is satisfactory.

IMPLICATION FOR NURSING PRACTICE:  Use of NANDA‐I nursing diagnoses should be encouraged among community health nurses.
Surface and Structural Modification of Nanostructured Mesoporous Silicon Oxycarbide Glasses Obtained from Preceramic Hybrids Aged in NH4OH
Authors: Tamayo Aitana , Rubio Fausto , Rubio Juan , Oteo José Luis
Published: October 2012

Highly meso‐porous silicon oxycarbide glasses have been obtained from preceramic hybrid materials aged in NH4OH solutions. Surface characterization reveals the amphoteric character of the surface because of the presence of carbon and silica nanodomains. The dependence of the surface Lewis base constant with the concentration of the NH4OH solution suggests different distribution in the carbon nanodomains because of the addition of the aging solution. Structural characterization reports on the increase in the crosslinking degree in the materials treated in NH4OH, whereas the number of dangling bonds increases significantly in the microporous material taken as a reference.
Fatigue Crack Growth Behavior of Silicon Nitride: Roles of Grain Aspect Ratio and Intergranular Film Composition
Authors: Greene Rawley B. , Fünfschilling Stefan , Fett Theo , Hoffmann Michael J. , Kruzic Jamie J.
Published: October 2012

The role of microstructure in affecting the fatigue crack growth resistance of grain bridging silicon nitride ceramics doped with rare earth (RE = Y, La, Lu) oxide sintering additives was investigated. Three silicon nitride ceramics were prepared using MgO‐RE2O3 and results were compared with a commercial Al2O3‐Y2O3‐doped material. Decreasing stress intensity range (ΔK) fatigue tests were conducted using compact‐tension specimens to measure steady‐state fatigue crack growth rates. Specimens doped with MgO‐RE2O3 additives showed a significantly higher resistance to crack growth than those with Al2O3‐Y2O3 additives and this difference was attributed to the much higher grain aspect ratio for the MgO‐RE2O3‐doped ceramics. When the crack growth data were normalized with respect to the total contribution of toughening by bridging determined from the monotonically loaded R‐curves, the differences in fatigue resistance were greatly reduced with the data overlapping considerably. Finally, all of the MgO‐RE2O3‐doped silicon nitrides displayed similar steady‐state fatigue crack growth behavior suggesting that they are relatively insensitive to the intergranular film.
Emission and Absorption Cross Sections at 810 and 860 nm Bands of Er3+ in LiNbO3 Crystal
Authors: Zhang De‐Long , Chen Bei , Hua Ping‐Rang , Pun Edwin Y.‐B.
Published: October 2012

We have measured the unpolarized and polarized emission spectra of 4I9/2→4I15/2 (810 nm) and 4S3/2→4I13/2 (860 nm) electronic transitions of Er3+ in LiNbO3 crystal under different incident directions and polarization states of excitation beam. From the measured emission spectra, the emission and absorption cross‐section spectra were calculated based upon McCumber theory. It is found that Er3+ electronic transition shows interesting excitation beam direction effect in polarization dependence, spectral shape, and cross‐section value. Both transitions are highly π‐polarized as the excitation beam was aligned perpendicular to the optical axis of crystal while being highly σ‐polarized as the excitation beam was oriented parallel to the optical axis of crystal. The spectral shape in the case of the perpendicular excitation is very different from that in the case of parallel excitation. The cross‐section value in the perpendicular excitation case is at least 1.5 times larger than that in the parallel excitation case. These excitation direction effects are independent of the polarization state of excitation light, and are attributed to the selective Er3+ site excitation. In addition, the Er3+ 860 nm emission lifetime was measured to be 27 ± 5 μs and the quantum efficiency of the emission is 2.5%.
Effects of Nonstoichiometry and Cocatalyst Loading on the Photocatalytic Hydrogen Production with (Y1.5Bi0.5)1−xTi2O7−3x and (YBi)1−xTi2O7−3x Pyrochlores
Authors: Merka Oliver , Raisch Olga , Steinbach Frank , Bahnemann Detlef W. , Wark Michael
Published: October 2012

By adjusting the Ti/(Y+Bi) ratios during synthesis, nonstoichiometric pyrochlores of (Y1.5Bi0.5)1−xTi2O7−3x and (YBi)1−xTi2O7−3x were prepared by an aqueous sol–gel method and annealed at different temperatures. The materials were characterized by X‐ray diffraction and UV–vis reflectance spectroscopy. The samples were tested for photocatalytic hydrogen production in the presence of methanol as sacrificial agent after being loaded with nanoparticles of rhodium or platinum acting as cocatalysts. It was found that materials being completely inactive in a stoichiometric composition can be tuned to good photocatalysts by optimizing the Ti/(Y+Bi) ratio. The increase in activity is supposed to derive from an optimization of the TiO6‐octahedral geometry due to the generation of vacancies inside the structure. Increasing the Bi loading shifts the absorption edge into the visible, but unfortunately, an increase of the bismuth content in the structure also leads to stability issues during photocatalysis, which can be suppressed or at least weakened by a higher cocatalyst loading.
The Influence of Dysprosium Addition on the Crystallization Behavior of a Chalcogenide Selenide Glass Close to the Fiber Drawing Temperature
Authors: Cheng Yin , Tang Zhuoqi , Neate Nigel C. , Furniss David , Benson Trevor M. , Seddon Angela B.
Published: October 2012

A series of chalcogenide glasses based on Ge16.5Ga3As16Se64.5 (at.%), doped nominally with 0, 1000, 3000, and 6000 ppmw (by weight) of Dy foil, is prepared by using conventional method: melting inside a sealed silica glass ampoule, which is rocked to homogenize the melt, followed by melt quenching and annealing. Examination of the as‐prepared glasses, using scanning electron microscopy with energy dispersive X‐ray spectroscopy (SEM‐EDX), reveals that dysprosium‐rich areas of devitrification have a tendency to form at the surfaces of the prepared chalcogenide glasses which have been adjacent the silica ampoule walls during the final stages of melting, quenching, and annealing; such dysprosium‐rich areas of devitrification are not observed using SEM‐EDX at the noncontacting‐silica‐ampoule chalcogenide glass surface nor in the interior of the chalcogenide glass bulk. Samples taken from the interior of the prepared glass boules exhibit an increase in glass transition of up to 9 ± 2°C, and rise in other isoviscous temperatures, with increasing dysprosium content. Extended isothermal heat treatment at the estimated fiber‐drawing temperature, followed by quenching to room temperature and analysis using SEM‐EDX and X‐ray diffraction (XRD), is carried out to investigate the influence of dysprosium addition on crystallization behavior on reheating the chalcogenide glass. Increasing the dysprosium level, surprisingly, appears on the one hand to help to restrain crystallization of the bulk glass on glass reheating, whereas on the other hand, and at the same time, to exacerbate the surface devitrification on glass reheating. The bulk crystallizing phase on reheating the glasses is distorted face‐centered cubic α‐Ga2Se3. The same phase was found to grow in the bulk glass during melt cooling of Dy‐doped Ge–As–Ga–Se glasses in our earlier work.
Gut travellers: internal dispersal of aquatic organisms by waterfowl
Authors: van Leeuwen Casper H. A. , van der Velde Gerard , van Groenendael Jan M. , Klaassen Marcel
Published: October 2012

Aim

Patterns of high biodiversity among less mobile organisms throughout isolated locations suggest that passive dispersal importantly contributes to biodiversity. We examined the contribution of waterbirds to the dispersal of plant seeds and macroinvertebrates between aquatic wetlands. Birds are renowned vectors for seeds of terrestrial plants, but less is known about their role in more dispersal‐dependent aquatic systems. We therefore performed a meta‐analysis on bird‐mediated endozoochorous dispersal of aquatic species.

Location

Our review included studies that collected data world‐wide.

Methods

We analysed data from 81 peer‐reviewed publications on endozoochorous dispersal of aquatic plant seeds and macroinvertebrates by waterbirds.

Results

In total, 36% of 1581 waterbird droppings collected in the field contained one or more intact propagules, with macroinvertebrates found almost as frequently as plant seeds. Positive droppings contained on average 3.3 intact propagules, of which one‐third were viable. In 728 trials from 17 published feeding experiments 24% of the ingested propagules were retrieved intact, with c. 6.5% both viable and intact. As many as 17 species of Anatidae and Rallidae were involved in the dispersal of at least 39 species of macroinvertebrates and seeds from 97 species of plants across a wide taxonomic range. Smaller propagules seemed less affected by digestion than larger ones. We provide a first quantitative model that can be used to estimate waterbird‐mediated dispersal of propagules between wetlands. This model indicates that an average waterbird has the potential to disperse five viable propagules after flying more than 100 km, and one additional propagule after flying 300 km.

Main conclusions

We demonstrate that waterbirds have the potential to transport a wide variety of aquatic plants and animals over several hundreds of kilometres. High survival of propagules might be explained by propagule adaptations or by the digestive adaptations of birds, whereby energy absorption is thought to be maximized rather than assimilation efficiency. Our meta‐analysis suggests that waterbirds might contribute significantly to wetland biodiversity around the world, despite several limitations to our current knowledge. We outline avenues for future research to address these knowledge gaps.
The cordierite‐bearing anatectic rocks of the higher Himalayan crystallines (eastern Nepal): low‐pressure anatexis, melt productivity, melt loss and the preservation of cordierite
Authors: GROPPO C. , ROLFO F. , MOSCA P.
Published: October 2012

Cordierite‐bearing anatectic rocks inform our understanding of low‐pressure anatectic processes in the continental crust. This article focuses on cordierite‐bearing lithologies occurring at the upper structural levels of the Higher Himalayan Crystallines (eastern Nepal Himalaya). Three cordierite‐bearing gneisses from different geological transects (from Mt Everest to Kangchenjunga) have been studied, in which cordierite is spectacularly well preserved. The three samples differ in terms of bulk composition likely reflecting different sedimentary protoliths, although they all consist of quartz, alkali feldspar, plagioclase, biotite, cordierite and sillimanite in different modal percentages. Analysis of the microstructures related to melt production and/or melt consumption allows the distinction to be made between peritectic and cotectic cordierite. The melt productivity of different prograde assemblages (from two‐mica metapelite/metagreywacke to biotite‐metapelite) has been investigated at low‐pressure conditions, evaluating the effects of muscovite v. biotite dehydration melting on both mineral assemblages and microstructures. The results of the thermodynamic modelling suggest that the mode and type of the micaceous minerals in the prograde assemblage is a very important parameter controlling the melt productivity at low‐pressure conditions, the two‐mica protoliths being significantly more fertile at any given temperature than biotite gneisses over the same temperature interval. Furthermore, the cordierite preservation is promoted by melt crystallization at a dry solidus and by exhumation along P‐T paths with a peculiar dP/dT slope of about 15–18 bar °C−1. Overall, our results provide a key for the interpretation of cordierite petrogenesis in migmatites from any low‐P regional anatectic terrane. The cordierite‐bearing migmatites may well represent the source rocks for the Miocene andalusite‐bearing leucogranites occurring at the upper structural levels of the Himalayan belt, and low‐P isobaric heating rather than decompression melting may be the triggering process of this peculiar peraluminous magmatism.
Macrophage migration inhibitory factor and oral cancer
Authors: França Cristiane M. , Batista Aline C. , Borra Ricardo C. , Ventiades‐Flores Jose A. , Mendonça Elismauro F. , Deana Alessandro M. , Mesquita‐Ferrari Raquel A. , de Natali Caly Decio , de Mello Rode Sigmar , Faria Miriam R.
Published: October 2012

Background

Macrophage migration inhibitory factor (MIF) is a pleiotropic cytokine with pro‐inflammatory functions and involved in tumorigenesis. The aim of this study was to evaluate the expression and localization of the macrophage MIF in oral squamous carcinoma (OSC). In addition, the relationship between MIF expression and clinicopathological parameters such as survival data, tobacco use, alcohol habits, TNM stage, tumor graduation, and peritumoral inflammatory infiltrate were evaluated.

Methods

Using immunohistochemistry, expression and localization of MIF was detected in 44 specimens of OSC. The absolute number and relative proportions of MIF‐positive cells detected were also determined separately for tumor parenchyma vs. stroma. All counts were determined from 10 consecutive high‐power fields using an integration graticule. Moreover, some parameters were analyzed separately for lip and intra‐oral cancers.

Results

Migration inhibitory factor‐positive cells were observed in both the tumor parenchyma and in inflammatory cells of all specimens. In contrast, MIF expression was not detected in tumoral nests associated with poorly differentiated tumors. In specimens of lip cancer, a greater number of MIF‐positive stromal immune cells were detected than in intra‐oral cancer specimens (Mann–Whitney test, P = 0.049).

Conclusions

Oral squamous carcinoma cells consistently express MIF independent of their location. Lip tumors presented more MIF‐positive peritumoral inflammatory cells, similar to control, suggesting that immunological differences in leukocyte activation exist between in lip and intra‐oral cancers.
Visual Detection of Potato leafroll virus by One‐step Reverse Transcription Loop‐Mediated Isothermal Amplification of DNA with Hydroxynaphthol Blue Dye
Authors: Ahmadi Sayvan , Almasi Mohammad A. , Fatehi Foad , Struik Paul C. , Moradi Aboubakr
Published: October 2012

Loop‐mediated isothermal amplification (LAMP) assay is a novel technique for amplifying DNA under constant temperature, with high specificity, sensitivity, rapidity and efficiency. We applied reverse transcription loop‐mediated isothermal amplification (RT‐LAMP) to visually detect Potato leafroll virus. One‐step RT‐LAMP was performed using RNA of PLRV‐infected potato leaves and a set of primers (F3, B3, FIP, BIP, LF and LB) designed for RT‐LAMP reaction of the coat protein (CP) gene of PLRV. Positive effects of RT‐LAMP were detected by agarose gel electrophoresis and hydroxynaphthol blue (HNB) dye and were shown by a colour change from violet to sky blue. RT‐LAMP with HNB dye proved to be a simple assay for the rapid detection of PLRV.
Dynamic tailoring of treatment durations improves efficiency of hepatitis C treatment with pegylated interferon and ribavirin
Authors: Lindh M. , Arnholm B. , Björkman P. , Hellstrand K. , Lagging M. , Nilsson S. , Wahlberg T. , Wallmark E. , Weiland O. , Wejstål R. , Westin J. , Widell A. , Norkrans G.
Published: October 2012

The treatment durations for hepatitis C are guided by the analysis of hepatitis C virus (HCV) RNA in blood at certain time points. This multicentre, randomized open label trial evaluated the utility and performance of individualized treatment durations guided by viral decline rates in 103 patients with HCV genotype 1 infection. Pegylated interferon 2a and ribavirin were given as standard of care (SOC) for 24, 48 or 72 weeks or as dynamic treatment (DT) for 24–72 weeks. The DT duration was based on the time point when log HCV RNA would reach 0 log copies/mL, as estimated by the second‐phase decline. The rate of sustained virologic response was 63% for SOC and 54% for DT, but this difference was not significant in multiple regression analysis taking predictive factors such as interleukin‐28B genotypes, age and baseline viremia into account (P = 0.45). The mean required treatment time per cured patient was 51 weeks for DT as compared with 58 weeks for SOC (P = 0.22) when given per protocol (n = 95) and was significantly shorter (42 vs 51 weeks) among patients who achieved undetectable HCV RNA (P = 0.01). We conclude that DT was feasible and increased efficiency. The estimated time point for 0 log viral copies/mL is a new and quantitative response variable, which may be used as a complement to the qualitative variable rapid virologic response. The outcome parameter treatment weeks per cured patient could become a useful tool for comparing treatment efficiency also in the era of directly acting antivirals.
Gastric secretion does not affect the reliability of the 13C‐acetate breath test: A validation of the 13C‐acetate breath test by magnetic resonance imaging
Authors: Kuyumcu S. , Goetze O. , Menne D. , Treier R. , Boesiger P. , Fox M. , Fried M. , Schwizer W. , Steingoetter A.
Published: October 2012

Background  13C‐Acetate labeled meals are widely used to determine meal emptying by means of analyzing resulting 13CO2 exhalation dynamics. In contrast to the underlying metabolic processes, only few 13C breath test meal emptying studies have focused on intragastric processes that may alter 13CO2 exhalation. This work assessed the effect of enhanced gastric secretion on the reliability of half emptying time (t50) measurements by 13C‐acetate breath test.

Methods  13CO2 exhalation data were acquired in a double‐blind, randomized, cross‐over gastric emptying study in 12 healthy volunteers receiving either pentagastrin or placebo intravenously. The standard method proposed by Ghoos et al. was applied to calculate t50 (t50_Ghoos) from 13CO2 exhalation data, which were compared and tested for agreement to meal half emptying times (t50_MV) from concurrent recorded MRI (magnetic resonance imaging) volume data. In addition, the accumulated gastric secretion volumes during infusion as detected by MRI (AUC_SV60) were correlated with the corresponding cumulative percent 13C doses recovered (cPDR60).

Key Results  t50_Ghoos and t50_MV showed a linear correlation with a slope of 1.1 ± 0.3 (r2 = 0.67), however, a positive offset of 136 min for t50_Ghoos. No correlation was detected between AUC_SV60 and cPDR60 (r2 = 0.11). Both, breath test and MRI, revealed a prolonged t50 under pentagastrin infusion with median differences in t50_Ghoos of 45[28–84] min (P = 0.002) and t50_MV of 39[28–52] min (P = 0.002).

Conclusions & Inferences  This study suggests that 13CO2 exhalation after ingestion of a 13C‐labeled liquid test meal is not affected by stimulated gastric secretion, but is rather reflecting the dynamics of meal or caloric emptying from the stomach.
The modification of plant oil composition via metabolic engineering—better nutrition by design
Authors: Haslam Richard P. , Ruiz‐Lopez Noemi , Eastmond Peter , Moloney Maurice , Sayanova Olga , Napier Johnathan A.
Published: October 2012

This article will focus on the modification of plant seed oils to enhance their nutritional composition. Such modifications will include C18 Δ6‐desaturated fatty acids such as γ‐linolenic and stearidonic acid, omega‐6 long‐chain polyunsaturated fatty acids such as arachidonic acid, as well as the omega‐3 long‐chain polyunsaturated fatty acids (often named ‘fish oils’) such as eicosapentaenoic acid and docosahexaenoic acid. We will consider how new technologies (such as synthetic biology, next‐generation sequencing and lipidomics) can help speed up and direct the development of desired traits in transgenic oilseeds. We will also discuss how manipulating triacylglycerol structure can further enhance the nutritional value of ‘designer’ oils. We will also consider how advances in model systems have translated into crops and the potential end‐users for such novel oils (e.g. aquaculture, animal feed, human nutrition).
Estimating the Causal Effect of Enforcement on Minimum Wage Compliance: The Case of South Africa
Authors: Bhorat Haroon , Kanbur Ravi , Mayet Natasha
Published: October 2012

This paper attempts to estimate the causal effect of government enforcement on compliance with minimum wages in South Africa, a country where considerable non‐compliance exists. The number of labor inspectors per capita is used as a proxy for enforcement, while non‐compliance is measured using an index of violation that measures both the proportion of individuals violated, as well as the average depth of individual violation. Because of the potential simultaneity between enforcement and compliance, the number of labor inspectors is instrumented by the number of non‐inspectors. The results suggest that there are a variety of factors impacting on violation, including firm‐level, sectoral, and spatial characteristics. One of the key determinants of violation is found to be the local unemployment rate. However, the number of labor inspectors is found to be insignificant in determining non‐compliance.
Physiological mechanisms for the modulation of pannexin 1 channel activity
Authors: Sandilos Joanna K. , Bayliss Douglas A.
Published: October 2012

Abstract  It is widely recognized that ATP, along with other nucleotides, subserves important intercellular signalling processes. Among various nucleotide release mechanisms, the relatively recently identified pannexin 1 (Panx1) channel is gaining prominence by virtue of its ability to support nucleotide permeation and release in a variety of different tissues. Here, we review recent advances in our understanding of the factors that control Panx1 channel activity. By using electrophysiological and biochemical approaches, diverse mechanisms that dynamically regulate Panx1 channel function have been identified in various settings; these include, among others, activation by caspase‐mediated channel cleavage in apoptotic immune cells, by G protein‐coupled receptors in vascular smooth muscle, by low oxygen tension in erythrocytes and neurons, by high extracellular K+ in various cell types and by stretch/strain in airway epithelia. Delineating the distinct mechanisms of Panx1 modulation that prevail in different physiological contexts provides the possibility that these channels, and ATP release, could ultimately be targeted in a context‐dependent manner.
Multiple pathways carry signals from short‐wavelength‐sensitive (‘blue’) cones to the middle temporal area of the macaque
Authors: Jayakumar Jaikishan , Roy Sujata , Dreher Bogdan , Martin Paul R. , Vidyasagar Trichur R.
Published: October 2012

Key points

The middle temporal area (area MT) of the macaque visual cortex receives visual signals from all three cone types, including short‐wavelength cones (S‐cones).

Signals from the short‐wavelength cones reach area MT both via the relay(s) in the primary visual cortex (V1) as well as a pathway bypassing V1.

The S‐cone signals to area MT that bypass V1 do not reach area MT significantly earlier than those that relay through V1.

The S‐cone signals that bypass V1 are most likely conveyed to area MT by direct projections from the koniocellular regions of the dorsal lateral geniculate nucleus.

Our results are consistent with the putative neuronal mechanism of the phenomenon of ‘blindsight’.

Abstract  We recorded spike activity of single neurones in the middle temporal visual cortical area (MT or V5) of anaesthetised macaque monkeys. We used flashing, stationary spatially circumscribed, cone‐isolating and luminance‐modulated stimuli of uniform fields to assess the effects of signals originating from the long‐, medium‐ or short‐ (S) wavelength‐sensitive cone classes. Nearly half (41/86) of the tested MT neurones responded reliably to S‐cone‐isolating stimuli. Response amplitude in the majority of the neurones tested further (19/28) was significantly reduced, though not always completely abolished, during reversible inactivation of visuotopically corresponding regions of the ipsilateral primary visual cortex (striate cortex, area V1). Thus, the present data indicate that signals originating in S‐cones reach area MT, either via V1 or via a pathway that does not go through area V1. We did not find a significant difference between the mean latencies of spike responses of MT neurones to signals that bypass V1 and those that do not; the considerable overlap we observed precludes the use of spike‐response latency as a criterion to define the routes through which the signals reach MT.
Evaluation of glutamate concentration transient in the synaptic cleft of the rat calyx of Held
Authors: Budisantoso Timotheus , Harada Harumi , Kamasawa Naomi , Fukazawa Yugo , Shigemoto Ryuichi , Matsui Ko
Published: October 2012

Key points

Spatiotemporal glutamate concentration profile in the cleft is a determinant of the EPSC amplitude and time course.

Two key parameters required to describe this profile are the number of glutamate in a vesicle (NGlu) and its diffusion coefficient (DGlu), both of which are unestablished.

Using the rat calyx of Held synapse as a model, the distribution of AMPA receptors was mapped with SDS‐digested freeze fracture replica labelling and their performance as glutamate sensors was evaluated with outside‐out patch recordings.

Based on these data, synaptic responses were simulated using various combinations of NGlu and DGlu, and an optimal range of the NGlu–DGlu combinations that could reproduce the recordings was determined.

Using the estimated profile, we show that release from a single vesicle does not saturate the receptors, glutamate spillover does not affect the synaptic conductance amplitude, and synaptic response increases non‐linearly with the number of multivesicular releases.

Abstract  Establishing the spatiotemporal concentration profile of neurotransmitter following synaptic vesicular release is essential for our understanding of inter‐neuronal communication. Such profile is a determinant of synaptic strength, short‐term plasticity and inter‐synaptic crosstalk. Synaptically released glutamate has been suggested to reach a few millimolar in concentration and last for <1 ms. The synaptic cleft is often conceived as a single concentration compartment, whereas a huge gradient likely exists. Modelling studies have attempted to describe this gradient, but two key parameters, the number of glutamate in a vesicle (NGlu) and its diffusion coefficient (DGlu) in the extracellular space, remained unresolved. To determine this profile, the rat calyx of Held synapse at postnatal day 12–16 was studied where diffusion of glutamate occurs two‐dimensionally and where quantification of AMPA receptor distribution on individual postsynaptic specialization on medial nucleus of the trapezoid body principal cells is possible using SDS‐digested freeze‐fracture replica labelling. To assess the performance of these receptors as glutamate sensors, a kinetic model of the receptors was constructed from outside‐out patch recordings. From here, we simulated synaptic responses and compared them with the EPSC recordings. Combinations of NGlu and DGlu with an optimum of 7000 and 0.3 μm2 ms−1 reproduced the data, suggesting slow diffusion. Further simulations showed that a single vesicle does not saturate the synaptic receptors, and that glutamate spillover does not affect the conductance amplitude at this synapse. Using the estimated profile, we also evaluated how the number of multiple vesicle releases at individual active zones affects the amplitude of postsynaptic signals.
Design of a Novel Compliant Transmission for Secondary Microactuators in Disk Drives
Authors: Kim Charles , Kota Sridhar
Published: October 2012

One of the bottlenecks limiting the data density in conventional disk drives is the resonant frequency of the suspension arm connecting the actuator and the read-write elements. In this paper we present a compliant transmission to be integrated with a secondary microactuator to deal with this limitation. The compliant transmission was designed to reduce overall footprint. This paper presents an optimization scheme which maximizes energy efficiency while constraining natural frequency, maximum stress, and axial loading. The final design meets both kinematic and dynamic criteria.
A Novel Method for Dynamic Modeling of Two Flexible Manipulators Grasping a Flexible Payload
Authors: Liu Ying-Chun , Yu Yue-Qing
Published: October 2012

Taking the flexible robot and payload as a closed flexible loop, a new model of two flexible manipulators grasping a flexible payload is proposed by using Finite Element Method. A numerical simulation of two flexible three-link arms manipulating a flexible beam is presented. The advantage of this method is illustrated by comparing with the coordinated dynamic model.
Dynamic Modeling of the Typical Industrial Cam-Follower System: Part 1 — Single-Degree-of-Freedom Models
Authors: Norton Robert L. , Gillis Charles A. , Maynard Corey N.
Published: October 2012

The extant literature on cam-follower system dynamic modeling is limited to the application configuration as commonly used in internal combustion valve trains. Many industrial application cam-follower trains are differently configured and require a somewhat different dynamic model. This paper develops several models suitable for these devices and compares their results to that of the classic valve-train model.
SPASUR: Interactive Visualization of the Coupler Surfaces of the Spatial 4C Mechanism
Authors: Larochelle Pierre M. , Agius Agnes
Published: October 2012

This paper presents a software tool entitled SPASUR (SPAtial SURface) for the interactive visualization of the coupler surfaces of the spatial 4C mechanism. The 4C mechanism is a two degree of freedom spatial four-bar linkage. The path traced by a point attached to the coupler or floating link defines a surface in space. An interactive graphical user interface has been created and integrated with kinematic analysis routines to generate and display these coupler surfaces. The result is a user-friendly and efficient means of generating and visualizing the coupler surfaces of the spatial 4C four-bar mechanism.
Design and Analysis of an Inherently-Compliant Light-Weight Active Hand Prosthesis
Authors: Yang Jingzhou , Abdel-Malek Karim , DeGraff D. , Pen˜a Pitarch E.
Published: October 2012

Design and prototyping of an Inherently cOmpliant light-Weight Active hand prosthesis (called the IOWA hand) is presented. The hand has five actuated fingers, four with two joints and the thumb with three joints. Each joint is designed using a novel flexible mechanism based on the loading of a compression spring in both transverse and axial directions and using cable-conduit systems. The rotational motion is transformed to tendon-like behavior, which enables the location of the actuators far from the arm (e.g., on a belt around the waist). The forward kinematics of the mechanism is also presented and lends itself well for computer control. It is shown that the solution of the transverse deflection of each finger segment is obtained in a general form, while the stiffness coefficients are obtained in closed form with small deflection angles and for the large angles we use FEM to solve it. A prototype finger is experimentally tested, the results verified, and the hand prosthesis is built.
Attenuation‐based estimation of patient size for the purpose of size specific dose estimation in CT. Part II. Implementation on abdomen and thorax phantoms using cross sectional CT images and scanned projection radiograph images
Authors: Wang Jia , Christner Jodie A. , Duan Xinhui , Leng Shuai , Yu Lifeng , McCollough Cynthia H.
Published: October 2012

Purpose:

To estimate attenuation using cross sectional CT images and scanned projection radiograph (SPR) images in a series of thorax and abdomen phantoms.

Methods:

Attenuation was quantified in terms of a water cylinder with cross sectional area ofAw from both the CT and SPR images of abdomen and thorax phantoms, where Aw is the area of a water cylinder that would absorb the same dose as the specified phantom. SPR and axial CT images were acquired using a dual‐source CT scanner operated at 120 kV in single‐source mode. To use the SPR image for estimating Aw, the pixel values of a SPR image were calibrated to physical water attenuation using a series of water phantoms. Aw and the corresponding diameter Dw were calculated using the derived attenuation‐based methods (from either CT or SPR image). Aw was also calculated using only geometrical dimensions of the phantoms (anterior‐posterior and lateral dimensions or cross sectional area).

Results:

For abdomen phantoms, the geometry‐based and attenuation‐based methods gave similar results forDw. Using only geometric parameters, an overestimation of Dw ranging from 4.3% to 21.5% was found for thorax phantoms. Results for Dw using the CT image and SPR based methods agreed with each other within 4% on average in both thorax and abdomen phantoms.

Conclusions:

Either the cross sectional CT or SPR images can be used to estimate patient attenuation in CT. Both are more accurate than use of only geometrical information for the task of quantifying patient attenuation. The SPR based method requires calibration of SPR pixel values to physical water attenuation and this calibration would be best performed by the scanner manufacturer.
MRI simulation for radiotherapy treatment planning
Authors: Devic Slobodan
Published: October 2012

Over the last two decades, the computed tomography simulator became the standard of the contemporary radiotherapy treatment planning (RTP) process. Along the same time, the superb soft tissue contrast of magnetic resonance imaging (MRI) was widely incorporated into RTP through the process of image coregistration. This review summarizes the efforts of incorporation of MRI data into target definition process for RTP based on gained clinical evidence so far and opens a question whether the time is up for bringing a MRI‐simulator as an additional standard imaging tool into radiation oncology departments.
Predicting the future from the past: An old problem from a modern perspective
Authors: Cecconi F. , Cencini M. , Falcioni M. , Vulpiani A.
Published: October 2012

The idea of predicting the future from the knowledge of the past is quite natural, even when dealing with systems whose equations of motion are not known. This long-standing issue is revisited in the light of modern ergodic theory of dynamical systems and becomes particularly interesting from a pedagogical perspective due to its close link with Poincaré’s recurrence. Using such a connection, a very general result of ergodic theory—Kac’s lemma—can be used to establish the intrinsic limitations to the possibility of predicting the future from the past. In spite of a naive expectation, predictability is hindered more by the effective number of degrees of freedom of a system than by the presence of chaos. If the effective number of degrees of freedom becomes large enough, whether the system is chaotic or not, predictions turn out to be practically impossible. The discussion of these issues is illustrated with the help of the numerical study of simple models.
TWEAK and cIAP1 Regulate Myoblast Fusion Through the Noncanonical NF-κB Signaling Pathway
Authors: Enwere Emeka K. , Holbrook Janelle , Lejmi-Mrad Rim , Vineham Jennifer , Timusk Kristen , Sivaraj Baktharaman , Isaac Methvin , Uehling David , Al-awar Rima , LaCasse Eric , Korneluk Robert G.
Published: October 2012

Muscle fiber formation from progenitor cells is dependent on noncanonical NF-κB signaling.
The Response of Cancers to BRAF Inhibition Underscores the Importance of Cancer Systems Biology
Authors: Stites Edward C.
Published: October 2012

Targeting the receptor and a mutant component may be an effective colon cancer treatment.
Feeling the Light
Authors: Ray L. Bryan
Published: October 2012

Light sensing involves contraction of the photoreceptor cell membrane physically gating the light-sensitive channels.
Neutrophils Generate Their Own Activators
Authors: Gough Nancy R.
Published: October 2012

Cathepsin G secreted from neutrophils cleaves proinflammatory precursors that function as autocrine signals.
A Preclinical Evaluation of Minnelide as a Therapeutic Agent Against Pancreatic Cancer
Authors: Chugh Rohit , Sangwan Veena , Patil Satish P. , Dudeja Vikas , Dawra Rajinder K. , Banerjee Sulagna , Schumacher Robert J. , Blazar Bruce R. , Georg Gunda I. , Vickers Selwyn M. , Saluja Ashok K.
Published: October 2012

Minnelide prevents tumor formation, causes tumor regression, and increases survival in multiple models of pancreatic cancer.
First Report of an OXA-23 Carbapenemase-Producing Acinetobacter baumannii Clinical Isolate Related to Tn
2006
in Spain
Authors: Espinal P. , Macià M. D. , Roca I. , Gato E. , Ruíz E. , Fernández-Cuenca F. , Oliver A. , Rodríguez-Baño J. , Bou G. , Tomás M. , Vila J.
Published: October 2012

A carbapenem-resistant
Acinetobacter baumannii
clinical isolate belonging to European clone II and sequence type 2 was recovered from a patient in the Son Espases hospital in Mallorca, Spain. Genetic analysis showed the presence of the
bla
OXA-23
gene in association with the widely disseminated transposon Tn
2006
. This is the first reported identification of
A. baumannii
carrying
bla
OXA-23
in Spain.
A Novel Inhibitor of Dengue Virus Replication That Targets the Capsid Protein
Authors: Byrd Chelsea M. , Dai Dongcheng , Grosenbach Douglas W. , Berhanu Aklile , Jones Kevin F. , Cardwell Kara B. , Schneider Christine , Wineinger Kristin A. , Page Jessica M. , Harver Chris , Stavale Eric , Tyavanagimatt Shanthakumar , Stone Melialani A. , Bartenschlager Ralf , Scaturro Pietro , Hruby Dennis E. , Jordan Robert
Published: October 2012

Dengue viruses (DENV) infect 50 to 100 million people worldwide per year, of which 500,000 develop severe life-threatening disease. This mosquito-borne illness is endemic in most tropical and subtropical countries and has spread significantly over the last decade. While there are several promising vaccine candidates in clinical trials, there are currently no approved vaccines or therapeutics available for treatment of dengue infection. Here, we describe a novel small-molecule compound, ST-148, that is a potent inhibitor of all four serotypes of DENV
in vitro
. ST-148 significantly reduced viremia and viral load in vital organs and tended to lower cytokine levels in the plasma in a nonlethal model of DENV infection in AG129 mice. Compound resistance mapped to the DENV capsid (C) gene, and a direct interaction of ST-148 with C protein is suggested by alterations of the intrinsic fluorescence of the protein in the presence of compound. Thus, ST-148 appears to interact with the DENV C protein and inhibits a distinct step(s) of the viral replication cycle.
Efficacy of Ethanol against Candida albicans and Staphylococcus aureus Polymicrobial Biofilms
Authors: Peters Brian M. , Ward Raven M. , Rane Hallie S. , Lee Samuel A. , Noverr Mairi C.
Published: October 2012

Candida albicans
, an opportunistic fungus, and
Staphylococcus aureus
, a bacterial pathogen, are two clinically relevant biofilm-forming microbes responsible for a majority of catheter-related infections, with such infections often resulting in catheter loss and removal. Not only do these pathogens cause a substantial number of nosocomial infections independently, but also they are frequently found coexisting as polymicrobial biofilms on host and environmental surfaces. Antimicrobial lock therapy is a current strategy to sterilize infected catheters. However, the robustness of this technique against polymicrobial biofilms has remained largely untested. Due to its antimicrobial activity, safety, stability, and affordability, we tested the hypothesis that ethanol (EtOH) could serve as a potentially efficacious catheter lock solution against
C. albicans
and
S. aureus
biofilms. Therefore, we optimized the dose and time necessary to achieve killing of both monomicrobial and polymicrobial biofilms formed on polystyrene and silicone surfaces in a static microplate lock therapy model. Treatment with 30% EtOH for a minimum of 4 h was inhibitory for monomicrobial and polymicrobial biofilms, as evidenced by XTT {sodium 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino)carbonyl]-2
H
-tetrazolium hydroxide inner salt} metabolic activity assays and confocal microscopy. Experiments to determine the regrowth of microorganisms on silicone after EtOH treatment were also performed. Importantly, incubation with 30% EtOH for 4 h was sufficient to kill and inhibit the growth of
C. albicans
, while 50% EtOH was needed to completely inhibit the regrowth of
S. aureus
. In summary, we have systematically defined the dose and duration of EtOH treatment that are effective against and prevent regrowth of
C. albicans
and
S. aureus
monomicrobial and polymicrobial biofilms in an
in vitro
lock therapy model.
Alginate Lyase Exhibits Catalysis-Independent Biofilm Dispersion and Antibiotic Synergy
Authors: Lamppa John W. , Griswold Karl E.
Published: October 2012

More than 2 decades of study support the hypothesis that alginate lyases are promising therapeutic candidates for treating mucoid
Pseudomonas aeruginosa
infections. In particular, the enzymes' ability to degrade alginate, a key component of mucoid biofilm matrix, has been the presumed mechanism by which they disrupt biofilms and enhance antibiotic efficacy. The systematic studies reported here show that, in an
in vitro
model, alginate lyase dispersion of
P. aeruginosa
biofilms and enzyme synergy with tobramycin are completely decoupled from catalytic activity. In fact, equivalent antibiofilm effects can be achieved with bovine serum albumin or simple amino acids. These results provide new insights into potential mechanisms of alginate lyase therapeutic activity, and they should motivate a careful reexamination of the fundamental assumptions underlying interest in enzymatic biofilm dispersion.