bluuebunny/crossref_metadata_2025 huggingface dataset:
Fracture propagation using the radial point interpolation method
Authors: Ramalho Luís D.C. , Belinha Jorge , Campilho Raul D.S.G.
Published: July 2019

This work presents a crack path prediction algorithm combined with the radial point interpolation method (RPIM), a meshless method. To allow easier implementation in existing structural analysis software, this algorithm is numerically compatible with finite element method (FEM) formulations. The proposed RPIM formulation uses the triangular elements of a FEM mesh as the background integration grid, allowing also to combine both formulations more easily. Thus, with the developed methodology, the RPIM can be integrated directly in a FEM software or use the same CAD tools to build the discretization meshes. Because the RPIM shape functions possess the delta Kronecker property, all the numerical techniques available for the FEM can be applied to enforce the natural and essential boundary conditions.

The developed algorithm uses the maximum tangential stress criterion to determine the crack propagation direction, and the crack paths obtained with it corresponded well to previous research.
Study of the influence of notch radii and temperature on the probability of failure: A methodology to perform a combined assessment
Authors: Muñiz‐Calvente Miguel , Álvarez‐Vázquez Adrián , Cicero Sergio , Correia José A.F.O. , de Jesus Abilio M.P. , Blasón Sergio , Fernández‐Canteli Alfonso , Berto Filippo
Published: July 2019

The fracture assessment of notched components based on cracked components approaches leads to over‐conservative failure predictions. In the research literature, several approaches are proposed to overcome this problem using an apparent fracture toughness,
. Nevertheless, most of these approaches are based on deterministic assumptions despite the large and variable scatter exhibited by
for different notch radii (ρ) or temperatures (T). This paper proposes a methodology for deriving a probabilistic
field including the effect of temperature on the failure of notched components. First, the theory of critical distances is applied to transform each apparent fracture toughness into the equivalent fracture toughness for ρ = 0. Then, the temperature is supposed to act as a scale effect in the Weibull cumulative distribution function of the equivalent fracture toughness, and the corresponding scale effect function is derived. Finally, the applicability of the proposed methodology is illustrated by an example using two ferritic‐pearlitic steels: S275JR and S355J2.
Do additive manufactured parts deserve better?
Authors: Yates John R. , Efthymiadis Panos , Antonysamy Alphons A. , Pinna Christophe , Tong Jie
Published: July 2019

Additive manufacturing of metallic components is regarded as one of the more exciting developments in engineering. The combined attractions of near net shape, tailored composition, and geometry optimisation have led to much interest in the various processes used and a drive to improve the mechanical properties to match those of wrought parts.

In this paper, we reflect on the apparent lack of ambition in optimising the structural integrity of parts made using these new manufacturing processes. The current research focus seems to be either on largely irrelevant static properties, or on quantifying the fatigue response in a way that would be familiar to engineers in the 19th Century.

Given the work on the role of microstructure and fatigue, which dates back to Ewing and Humphrey in 1903 reaching its zenith in the 1980s and 90s with Keith Miller in the vanguard, and recent developments in both imaging technologies and sophisticated numerical modelling, all the elements are in place for a much more rigorous, and ultimately more fruitful, approach to understand the structural integrity of additive manufactured components.
Do lakes feel the burn? Ecological consequences of increasing exposure of lakes to fire in the continental United States
Authors: McCullough Ian M. , Cheruvelil Kendra Spence , Lapierre Jean‐François , Lottig Noah R. , Moritz Max A. , Stachelek Jemma , Soranno Patricia A.
Published: July 2019

Wildfires are becoming larger and more frequent across much of the United States due to anthropogenic climate change. No studies, however, have assessed fire prevalence in lake watersheds at broad spatial and temporal scales, and thus it is unknown whether wildfires threaten lakes and reservoirs (hereafter, lakes) of the United States. We show that fire activity has increased in lake watersheds across the continental United States from 1984 to 2015, particularly since 2005. Lakes have experienced the greatest fire activity in the western United States, Southern Great Plains, and Florida. Despite over 30 years of increasing fire exposure, fire effects on fresh waters have not been well studied; previous research has generally focused on streams, and most of the limited lake‐fire research has been conducted in boreal landscapes. We therefore propose a conceptual model of how fire may influence the physical, chemical, and biological properties of lake ecosystems by synthesizing the best available science from terrestrial, aquatic, fire, and landscape ecology. This model also highlights emerging research priorities and provides a starting point to help land and lake managers anticipate potential effects of fire on ecosystem services provided by fresh waters and their watersheds.
Drought decreases incorporation of recent plant photosynthate into soil food webs regardless of their trophic complexity
Authors: Chomel Mathilde , Lavallee Jocelyn M. , Alvarez‐Segura Nil , de Castro Francisco , Rhymes Jennifer M. , Caruso Tancredi , de Vries Franciska T. , Baggs Elizabeth M. , Emmerson Mark C. , Bardgett Richard D. , Johnson David
Published: July 2019

Theory suggests that more complex food webs promote stability and can buffer the effects of perturbations, such as drought, on soil organisms and ecosystem functions. Here, we tested experimentally how soil food web trophic complexity modulates the response to drought of soil functions related to carbon cycling and the capture and transfer below‐ground of recent photosynthate by plants. We constructed experimental systems comprising soil communities with one, two or three trophic levels (microorganisms, detritivores and predators) and subjected them to drought. We investigated how food web trophic complexity in interaction with drought influenced litter decomposition, soil CO2efflux, mycorrhizal colonization, fungal production, microbial communities and soil fauna biomass. Plants were pulse‐labelled after the drought with13C‐CO2to quantify the capture of recent photosynthate and its transfer below‐ground. Overall, our results show that drought and soil food web trophic complexity do not interact to affect soil functions and microbial community composition, but act independently, with an overall stronger effect of drought. After drought, the net uptake of13C by plants was reduced and its retention in plant biomass was greater, leading to a strong decrease in carbon transfer below‐ground. Although food web trophic complexity influenced the biomass of Collembola and fungal hyphal length,13C enrichment and the net transfer of carbon from plant shoots to microbes and soil CO2efflux were not affected significantly by varying the number of trophic groups. Our results indicate that drought has a strong effect on above‐ground–below‐ground linkages by reducing the flow of recent photosynthate. Our results emphasize the sensitivity of the critical pathway of recent photosynthate transfer from plants to soil organisms to a drought perturbation, and show that these effects may not be mitigated by the trophic complexity of soil communities, at least at the level manipulated in this experiment.
Plant phylogenetic diversity stabilizes large‐scale ecosystem productivity
Authors: Mazzochini Guilherme G. , Fonseca Carlos R. , Costa Gabriel C. , Santos Rubens M. , Oliveira‐Filho Ary T. , Ganade Gislene
Published: July 2019

Aim

Global carbon cycle models do not incorporate the stabilizing effect of biodiversity on productivity despite this phenomenon has been widely described in several local scale manipulative experiments. The reason is a lack of evidence supporting the importance of biodiversity on spatial scales at which climate models are built. Here, we test the hypothesis that diversity enhances productivity stability at a large scale.

Location

South American dryland known as Caatinga (~830,000 km2).

Time period

2001–2010.

Major taxa studied

Woody plants.

Methods

We used the enhanced vegetation index of Caatinga vegetation remnants, from 2001 to 2010, to calculate vegetation productivity stability across years. We used occurrence records of 606 woody species from floristic surveys to derive species richness and phylogenetic diversity at ~5 km and ~55 km (0.5°) resolution. Climate data were obtained from global databases.

Results

Plant phylogenetic diversity has a strong positive correlation with productivity stability even after controlling for several climatic variables, such as rainfall, temperature and cloudiness, at both resolutions. Species richness was not significant when climatic variables were included.

Main conclusions

This result expands by several orders of magnitude the spatial scale of the evidence that biodiversity strengths the resilience of key ecosystem functions. We highlight that, by incorporating plant phylogenetic diversity, regional and global climate models can generate more accurate predictions about future ecosystem functioning and services that are critical to humankind.
The launch and evolution of a technology‐based economy: The case of Austin Texas
Authors: Gibson David , Oden Michael
Published: July 2019

This paper uses the lens of institutional theory to explain the launch and evolution of Austin, Texas's technology‐based economy. The case underscores the importance of context, contingency, and the evolution of key local development organizations in explaining how regional economic development trajectories can change and evolve. The case history provides insights into how economic development networks form and operate to “set off” processes of industrial specialization and agglomeration and how they can promote successful adaptation to change in technology and industrial structure. The Austin story further suggests a “stage” process of regional technology‐based evolution where the development of industrial agglomerations linked to a substantial local research base is seen as a necessary precursor to increasing endogenous innovation and start‐up activity. Successfully navigating these stages is bolstered by the formation of institutions and networks that are durable, strategic, and adaptive, and which, at the right time, recognize and support entrepreneurial firm development to help sustain technology‐based growth.
Detection of Helicobacter pylori with clarithromycin resistance‐associated mutations using peptide nucleic acid probe‐based melting point analysis
Authors: Nahm Ji Hae , Kim Won Kyu , Kwon Yujin , Kim Hyunki
Published: July 2019

Background

Detection of Helicobacter pylori in gastric biopsy is important for appropriate treatment and prevention of gastric carcinoma and lymphoma. A novel peptide nucleic acid probe (PNA)‐based real‐time polymerase chain reaction (PCR) method was developed for detection of H pylori and A2142G/A2143G mutation of the 23S rRNA gene, which is associated with clarithromycin resistance.

Methods

To evaluate the performance of the PNA probe‐based PCR method, a total of 409 gastric biopsy samples were analyzed by PNA probe‐based PCR and compared with other H pylori detection methods, including hematoxylin and eosin (HE) and Warthin‐Starry (WS) staining, immunohistochemistry (IHC). A2142G/A2143G mutation of the 23S rRNA gene was tested by dual priming oligonucleotide (DPO)‐based PCR and Sanger sequencing to evaluate PNA probe‐based PCR.

Results

Among 271 cases that were positive for H pylori on IHC which was considered as a standard method, 264 cases (97.4%) and 259 cases (95.6%) were positively detected by HE/WS and PNA probe‐based qPCR, respectively. Of 100 H pylori‐positive patients tested by IHC, H pylori was detected in 93 cases (93.0%) by PNA probe‐based PCR, 86 cases (86.0%) by DPO‐based PCR, and 93 cases (93.0%) by conventional PCR. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of PNA probe‐based qPCR were 93.0%, 94.9%, 93.9%, 94.9%, and 93.0%, respectively, which were all higher than those of DPO‐based PCR. When Sanger sequencing was determined as a standard method to detect A2142G/A2143G mutations, the sensitivity of the PNA‐ and DPO‐based methods was 100% and 94.4%, respectively, and the specificity was 100% for both methods.

Conclusion

PNA probe‐based qPCR is an appropriate method for detecting H pylori and the clarithromycin resistance‐associated mutation type.
Natural and experimental structural evolution of dispersed organic matter in mudstones: The Shimanto accretionary complex, southwest Japan
Authors: Nakamura Yoshihiro , Hara Hidetoshi , Kagi Hiroyuki
Published: July 2019

Structural changes induced by thermal maturation of dispersed organic matter (OM) in the Shimanto accretionary complex, southwest Japan, were investigated using micro‐Fourier‐transform infrared spectroscopy and micro‐Raman spectroscopy. Natural dispersed OM exhibits systematic structural changes inferred from D1‐ and G‐band FWHM values, Raman band separation (RBS), and intensity ratios of the D1‐ and G‐bands (ID1/IG ratio) from diagenetic zone to anchizone (IC values: 0.75–0.30). Infrared spectra indicate a loss of aliphatic CH
x, aromatic CH
x, and oxygen‐containing structures as temperature increases. These changes are consistent with discontinuities in thermal structures bounded by out‐of‐sequence thrusts. Kinetic pyrolysis experiments indicate that the ID1/IG ratio of synthesized OM has a power law relationship with heat treatment time. Kinetic models of temperature dependence were fitted using the ID1/IG ratio, and an effective activation energy of 106 ±17 kJ/mol was estimated using an Arrhenius equation. The activation energies estimated by power law rate and Avrami models have a least‐square correlation coefficient of 0.93, indicating the temperature dependence of carbonization. The estimated effective activation energy is consistent with that of coal, lignin, cellulose, and hemicellulose during thermal degradation. On the other hand, RBS, and D1‐ and G‐band FWHM values of OM display more complex changes with increasing heating temperature and time, and it is difficult to constrain rate parameters during pyrolysis experiments. Our data indicate that the ID1/IG ratio is controlled by a simple thermally activated process, whereas RBS and D1‐ and G‐band FWHM values can be affected by lithostatic pressure, fluid activity, hydrogen index, and host lithology, as well as temperature. Structural evolution of dispersed OM in mudstones differs between natural and anhydrous closed experimental systems. Natural carbonization based on micro‐Raman spectroscopy should be applied for a limited indicator of thermal maturation, especially for dispersed OM in diagenetic zone.
From Zero to Hero? An analysis of the human rights protections within the Global Compact for Safe, Orderly and Regular Migration (GCM)
Authors: Guild Elspeth , Basaran Tugba , Allinson Kathryn
Published: July 2019

This article examines the Global Compact for Safe, Orderly and Regular Migration (GCM) from three perspectives: First, while the GCM is not legally binding, the human rights obligations of states which underpin the GCM are. The application of international human rights law to everyone, including migrants, has led to frictions in the inter‐governmental negotiation process, with some states declining to sign the GCM. States cannot relieve themselves of the human rights obligations to which they are already, voluntarily, bound by refusing to sign the GCM. Second, the GCM asserts the human rights of migrants, and by implication condemns state practices contrary thereto, but it also yields to political sensitivities. Thus, we encounter a Compact that defends existing human rights standards, but concurrently submits to political will and tolerates conditions of vulnerability. Third, the GCM’s implementation depends upon, as yet undefined, partnerships with non‐State actors and monitoring against human rights standards.
High‐entropy, phase‐constrained, lanthanide sesquioxide
Authors: Tseng Kuo‐Pin , Yang Qun , McCormack Scott J. , Kriven Waltraud M.
Published: July 2019

Oxides can experience structural transformations resulting from variations in cation oxidation states or coordination geometry upon thermal treatment. Whether such structural distortions can affect the stability of high‐entropy oxides has not been studied. In this research, a new, high‐entropy, lanthanide sesquioxide, Gd0.4Tb0.4Dy0.4Ho0.4Er0.4O3 solid solution having a single phase, cubic‐bixbyite structure was synthesized, with no phase transformation from room temperature to 1650°C. The phase stability was examined via both in situ and ex situ, high‐temperature, synchrotron, X‐ray powder diffraction. This high‐entropy oxide could inhibit the phase transformations occurring in constituent monocation sesquioxides, Tb2O3 and Gd2O3, via random arrangement of multications.
Hypertension and patients with acute coronary syndrome: Putting blood pressure levels into perspective
Authors: Konstantinou Konstantinos , Tsioufis Costas , Koumelli Areti , Mantzouranis Manos , Kasiakogias Alexandros , Doumas Michalis , Tousoulis Dimitris
Published: July 2019

Arterial hypertension is a well‐established cardiovascular risk factor, and blood pressure (BP) control has largely improved the prognosis of hypertensive patients. A number of studies have assessed the role of BP levels in the prognosis of patients with acute coronary syndromes. Pathophysiologic links of hypertension to acute myocardial infarction (MI) include endothelial dysfunction, autonomic nervous system dysregulation, impaired vasoreactivity, and a genetic substrate. A history of hypertension is highly prevalent among patients presenting with MI, and some, but not all, studies have associated it with a worse prognosis. Some data support that low levels of admission and in‐hospital BP may indicate an increased risk for subsequent events. Risk scores used in patients with MI have, therefore, included BP levels and a history of hypertension in their variables. Of note, good long‐term BP control, ideally initiated prior to discharge, should be pursued in order to improve secondary prevention.
MicroRNA‐125b in vascular diseases: An updated systematic review of pathogenetic implications and clinical applications
Authors: Chao Chia‐Ter , Yeh Hsiang‐Yuan , Yuan Tzu‐Hang , Chiang Chih‐Kang , Chen Huei‐Wen
Published: July 2019

Epigenetic changes, particularly non‐coding RNAs, have been implicated extensively in the pathogenesis of vascular diseases. Specific miRNAs are involved in the differentiation, phenotypic switch, proliferation, apoptosis, cytokine production and matrix deposition of endothelial cells and/or vascular smooth muscle cells. MicroRNA‐125b has been studied in depth for its role in carcinogenesis with a double‐edged role; that is, it can act as an oncogene in some cancer types and as a tumour suppressor gene in others. However, cumulative evidence from the use of advanced miRNA profiling techniques and bioinformatics analysis suggests that miR‐125b can be a potential mediator and useful marker of vascular diseases. Currently, the exact role of miR‐125b in vascular diseases is not known. In this systematic review, we intend to provide an updated compilation of all the recent findings of miR‐125b in vascular diseases, using a systematic approach of retrieving data from all available reports followed by data summarization. MiR‐125b serves as a pathogenic player in multiple vascular pathologies involving endothelia and vascular smooth muscle cells and also serves as a diagnostic marker for vascular diseases. We further provide a computational biologic presentation of the complex network of miR‐125b and its target genes within the scope of vascular diseases.
Adalimumab for nail psoriasis: efficacy and safety over 52 weeks from a phase‐3, randomized, placebo‐controlled trial
Authors: Elewski B.E. , Baker C.S. , Crowley J.J. , Poulin Y. , Okun M.M. , Calimlim B. , Geng Z. , Reyes Servin O. , Rich P.A.
Published: July 2019

Background

Few clinical trials have evaluated long‐term treatment of nail psoriasis with biologics.

Objective

Safety and efficacy of adalimumab [ADA; Humira AbbVie Inc, North Chicago, IL, USA)] long‐term treatment (52 weeks) was evaluated in a phase‐3, randomized trial in patients with moderate‐to‐severe plaque psoriasis and concomitant moderate‐to‐severe fingernail psoriasis. Results from the first 26 weeks (Period A) have been reported.

Methods

Patients receiving 40 mg ADA every other week or placebo in Period A, continued with or switched to 40 mg ADA every‐other‐week treatment in the subsequent 26‐week open‐label extension (OLE) period. Main efficacy evaluations were ≥75% improvement in total‐fingernail modified Nail Psoriasis Severity Index (mNAPSI 75) and achievement of Physician's Global Assessment for Fingernail Psoriasis of clear or minimal disease (PGA‐F 0/1) with a ≥2‐grade improvement from baseline, across the trial for patients who continued ADA from Period A through the OLE (Continuous‐ADA Population). Safety was evaluated during the OLE and for patients receiving ADA at any time during the study (All‐ADA Population).

Results

Of the 217 patients initially randomized in Period A, 188 (86.6%; 94 in each treatment group) entered the OLE after completion of or early escape from Period A. For the Continuous‐ADA Population (N = 109), endpoint achievement rates improved from OLE entry (Week 26) to Week 52, including total‐fingernail mNAPSI 75 (47.4–54.5%); PGA‐F 0/1 (51.1–55.6%) and total‐fingernail mNAPSI = 0 (6.6–17.9%). Serious adverse event and serious infection rates for the All‐ADA Population (N = 203) were 6.9% and 3.4%, respectively.

Conclusions

In this population of psoriasis patients with concomitant, moderate‐to‐severe nail psoriasis, long‐term efficacy and improvement in signs and symptoms of nail disease were demonstrated after every‐other‐week ADA treatment, including incremental improvements in rate of total clearance of nail disease. No new safety risks were identified for patients receiving at least one ADA dose across 52 weeks.
Determination of drying kinetics, some physical, and antioxidant properties of papaya seeds undergoing microwave vacuum drying
Authors: Bualuang Oraporn , Onwude Daniel I. , Uso Aneesah , Peerachaakkarachai Kankulnat , Mora Pimpalak , Dulsamphan Suphak , Sena Pairot
Published: July 2019

The effects of microwave power (MP, 100–600 W) on the drying kinetics, as well as the physical and antioxidant properties of papaya seeds dried under microwave vacuum drying (MVD) were investigated. The results found that moisture diffusivity increased in the order of 10−8 with an increase in MP. Shrinkage increased from 1.2 to 4.9% and bulk density decreased from 3,441 to 1,091 kg/m3, respectively, while the moisture content decreased. The antioxidant contents of all of the MVD samples were higher than those of the samples dried under ambient air ventilation. An increase in MP decreased the total phenolic content from 14.69 to 10.66 mg gallic acid equivalent per gram dry weight (DW), increased both the β‐carotene and the total flavonoid content in the ranges of 0.2–0.35 mg β‐carotene equivalent per gram DW and 20.71 to 23.51 mg catechin equivalent per gram DW, respectively. Higher values of antioxidant activity were obtained at higher MP. The results have shown that the use of novel MVD technique in appropriate conditions can improve the overall drying efficiency and enhance the total yield of antioxidant content.

Practical Applications

Papaya seeds have great potential for use as a source of antioxidants. However, the best novel techniques for retaining high values of antioxidant compounds, and therefore recouping value from the wasted seeds, has not been widely reported on. This study has found that combined microwave vacuum drying (MVD) is a very beneficial drying method for the preservation of antioxidant content. A better antioxidant yield from dried papaya seeds was obtained using MVD at a higher MP of 600 W. Trolox equivalent antioxidant capacity of seeds dried using MVD was 27.62% higher than the samples dried using ambient air ventilation.
Loss of Community‐Dwelling Status Among Survivors of High‐Acuity Emergency General Surgery Disease
Authors: Smith Jason W. , Knight Davis Jennifer , Quatman‐Yates Catherine C. , Waterman Brittany L. , Strassels Scott A. , Wong Jen D. , Heh Victor K. , Baselice Holly E. , Brock Guy N. , Clark Brian C. , Bridges John F.P. , Santry Heena P.
Published: July 2019

OBJECTIVES

To examine loss of community‐dwelling status 9 months after hospitalization for high‐acuity emergency general surgery (HA‐EGS) disease among older Americans.

DESIGN

Retrospective analysis of claims data.

SETTING

US communities with Medicare beneficiaries.

PARTICIPANTS

Medicare beneficiaries age 65 years or older hospitalized urgently/emergently between January 1, 2015, and March 31, 2015, with a principal diagnosis representing potential life or organ threat (necrotizing soft tissue infections, hernias with gangrene, ischemic enteritis, perforated viscus, toxic colitis or gastroenteritis, peritonitis, intra‐abdominal hemorrhage) and an operation of interest on hospital days 1 or 2 (N = 3319).

MEASUREMENTS

Demographic characteristics (age, race, and sex), comorbidities, principal diagnosis, complications, and index hospitalization disposition (died; discharged to skilled nursing facility [SNF], long‐term acute care [LTAC], rehabilitation, hospice, home (with or without services), or acute care hospital; other) were measured. Survivors of index hospitalization were followed until December 31, 2015, on mortality and community‐dwelling status (SNF/LTAC vs not). Descriptive statistics, Kaplan‐Meier plots, and χ2 tests were used to describe and compare the cohort based on disposition. A multivariable logistic regression model, adjusted for age, sex, comorbidities, complications, and discharge disposition, determined independent predictors of loss of community‐dwelling status at 9 months.

RESULTS

A total of 2922 (88%) survived index hospitalization. Likelihood of discharge to home decreased with increasing age, baseline comorbidities, and in‐hospital complications. Overall, 418 (14.3%) HA‐EGS survivors died during the follow‐up period. Among those alive at 9 months, 10.3% were no longer community dwelling. Initial discharge disposition to any location other than home and three or more surgical complications during index hospitalization were independent predictors of residing in a SNF/LTAC 9 months after surviving HA‐EGS.

CONCLUSION

Older Americans, known to prioritize living in the community, will experience substantial loss of independence due to HA‐EGS. Long‐term expectations after surviving HA‐EGS must be framed from the perspective of the outcomes that older patients value the most. Further research is needed to examine the quality‐of‐life burden of EGS survivorship prospectively. J Am Geriatr Soc 67:2289–2297, 2019
Health indicators as moderators of occupational commitment and nurses' intention to leave
Authors: Asakura Kyoko , Asakura Takashi , Satoh Miho , Watanabe Ikue , Hara Yukari
Published: July 2019

Aim

This study examined the hypothesis that health indicators moderate the relationship between occupational commitment and intention to leave among nurses, using a large sample in Japan.

Methods

A self‐administered questionnaire was distributed to all registered nurses (N = 11,171) working in group hospitals in western Japan in 2014. The questionnaire evaluated intention to leave, occupational commitment, psychological distress, cumulative fatigue, and demographic variables. After a preliminary analysis of the bivariate and multivariate associations between variables and intention to leave, we tested the interactions between occupational commitment and health indicators on intention to leave.

Results

Of the 5,768 returned questionnaires, data from 5,505 (49.3%) participants were analyzed. Participants' mean age was 36.27 years (SD = 10.37). Most (95.14%) were women. According to a generalized estimating equation, the interaction of continuance occupational commitment and cumulative fatigue was significantly related to intention to leave (b = −0.0055). Additionally, the interaction of affective occupational commitment and psychological distress was significantly related to intention to leave (b = 0.0079).

Conclusions

This study clarified that the relationship between occupational commitment and intention to leave was robust for nurses in good health. Interventions aimed at reducing fatigue and improving psychological distress should be implemented to prevent the protective effects of occupational commitment on nurses' intention to leave from being compromised.
Displacement fields using correlation methods as a tool to investigate cell migration in 3D collagen gels
Authors: FERTIN ARNOLD , LAFORGUE LAURE , DUPERRAY ALAIN , LAURENT VALÉRIE M. , USSON YVES , VERDIER CLAUDE
Published: July 2019

Living cells embedded in a complex extra‐cellular matrix migrate in a sophisticated way thanks to adhesions to matrix fibres and contractility. It is important to know what kind of forces are exerted by the cells. Here, we use reflectance confocal microscopy to locate fibres accurately and determine displacement fields. Correlation techniques are used to this aim, coupled with proper digital image processing. Benchmark tests validate the method in the case of shear and stretching motions. Finally, the method is tested successfully for studying cancer cells migrating in collagen gels of different concentration.
Angiotensin II mediates the axonal trafficking of tyrosine hydroxylase and dopamine β‐hydroxylase mRNAs and enhances norepinephrine synthesis in primary sympathetic neurons
Authors: Aschrafi Armaz , Berndt Adama , Kowalak Jeffrey A. , Gale Jenna R. , Gioio Anthony E. , Kaplan Barry B.
Published: July 2019

In the sympatho‐adrenal system, angiotensin II (Ang II) acts as a key neuromodulatory component. At sympathetic nerve terminals, Ang II influences sympathetic transmission by enhancing norepinephrine (NE) synthesis, facilitating NE release and inhibiting NE uptake. Previously, it was demonstrated that tyrosine hydroxylase (TH) mRNA is trafficked to the distal axons of primary superior cervical ganglia (SCG) neurons, directed by a cis‐acting regulatory element (i.e. zipcode) located in the 3'UTR of the transcript. Results of metabolic labeling studies established that the mRNA is locally translated. It was further shown that the axonal trafficking of the mRNA encoding the enzyme plays an important role in mediating dopamine (DA) and NE synthesis and may facilitate the maintenance of axonal catecholamine levels. In the present study, the hypothesis was tested that Ang II induces NE synthesis in rat primary SCG neurons via the modulation of the trafficking of the mRNAs encoding the catecholamine synthesizing enzymes TH and dopamine β‐hydroxylase (DBH). Treatment of SCG neurons with the Ang II receptor type 1 (AT1R) agonist, L‐162,313, increases the axonal levels of TH and DBH mRNA and protein and results in elevated NE levels. Conversely, treatment of rat SCG neurons with the AT1R antagonist, Eprosartan, abolished the L‐162,313‐mediated increase in axonal levels of TH and DBH mRNA and protein. In a first attempt to identify the proteins involved in the Ang II‐mediated axonal transport of TH mRNA, we used a biotinylated 50‐nucleotide TH RNA zipcode as bait in the affinity purification of TH zipcode‐associated proteins. Mass spectrometric analysis of the TH zipcode ribonucleoprotein (RNP) complex immune‐purified from SCG neurons led to the identification of 163 somal and 127 axonal proteins functionally involved in binding nucleic acids, the translational machinery or acting as subunits of cytoskeletal and motor proteins. Surprisingly, immune‐purification of the TH axonal trafficking complex, results in the acquisition of DBH mRNA, suggesting that these mRNAs maybe transported to the axon together, possibly in the same RNP complex. Taken together, our results point to a novel mechanism by which Ang II participates in the regulation of axonal synthesis of NE by modulating the local trafficking and expression of TH and DBH, two key enzymes involved in the catecholamine biosynthetic pathway.

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Resting‐State fMRI Networks in Children with Tuberous Sclerosis Complex
Authors: Ahtam Banu , Dehaes Mathieu , Sliva Danielle D. , Peters Jurriaan M. , Krueger Darcy A. , Bebin Elizabeth Martina , Northrup Hope , Wu Joyce Y. , Warfield Simon K. , Sahin Mustafa , Grant Patricia Ellen ,   on behalf of the TACERN Study Group
Published: July 2019

BACKGROUND AND PURPOSE

There are no published studies examining resting state networks (RSNs) and their relationship with neurodevelopmental metrics in tuberous sclerosis complex (TSC). We aimed to identify major resting‐state functional magnetic resonance imaging (rs‐fMRI) networks in infants with TSC and correlate network analyses with neurodevelopmental assessments, autism diagnosis, and seizure history.

METHODS

Rs‐fMRI data from 34 infants with TSC, sedated with propofol during the scan, were analyzed to identify auditory, motor, and visual RSNs. We examined the correlations between auditory, motor, and visual RSNs at approximately 11.5 months, neurodevelopmental outcome at approximately 18.5 months, and diagnosis of autism spectrum disorders at approximately 36 months of age.

RESULTS

RSNs were obtained in 76.5% (26/34) of infants. We observed significant negative correlations between auditory RSN and auditory comprehension test scores (p = .038; r = −.435), as well as significant positive correlations between motor RSN and gross motor skills test scores (p = .023; r = .564). Significant positive correlations between motor RSNs and gross motor skills (p = .012; r = .754) were observed in TSC infants without autism, but not in TSC infants with autism, which could suggest altered motor processing. There were no significant differences in RSNs according to seizure history.

CONCLUSIONS

Negative correlation between auditory RSN, as well as positive correlation between motor RSN and developmental outcome measures might reflect different brain mechanisms and, when identified, may be helpful in predicting later function. A larger study of TSC patients with a healthy control group is needed before auditory and motor RSNs could be considered as neurodevelopmental outcome biomarkers.
A direct solution method for pricing options in regime‐switching models
Authors: Egami Masahiko , Kevkhishvili Rusudan
Published: July 2019

Pricing financial or real options with arbitrary payoffs in regime‐switching models is an important problem in finance. Mathematically, it is to solve, under certain standard assumptions, a general form of optimal stopping problems in regime‐switching models. In this article, we reduce an optimal stopping problem with an arbitrary value function in a two‐regime environment to a pair of optimal stopping problems without regime switching. We then propose a method for finding optimal stopping rules using the techniques available for nonswitching problems. In contrast to other methods, our systematic solution procedure is more direct as we first obtain the explicit form of the value functions. In the end, we discuss an option pricing problem, which may not be dealt with by the conventional methods, demonstrating the simplicity of our approach.
Assessors’ interpretations of narrative data on communication skills in a summative OSCE
Authors: Wilby Kyle John , Dolmans Diana H J M , Austin Zubin , Govaerts Marjan J B
Published: July 2019

Objectives

Increasingly, narrative assessment data are used to substantiate and enhance the robustness of assessor judgements. However, the interpretation of written assessment comments is inherently complex and relies on human (expert) judgements. The purpose of this study was to explore how expert assessors process and construe or bring meaning to narrative data when interpreting narrative assessment comments written by others in the setting of standardised performance assessment.

Methods

Narrative assessment comments on student communication skills and communication scores across six objective structured clinical examination stations were obtained for 24 final‐year pharmacy students. Aggregated narrative data across all stations were sampled for nine students (three good, three average and three poor performers, based on communication scores). A total of 10 expert assessors reviewed the aggregated set of narrative comments for each student. Cognitive (information) processing was captured through think‐aloud procedures and verbal protocol analysis.

Results

Expert assessors primarily made use of two strategies to interpret the narratives, namely comparing and contrasting, and forming mental images of student performance. Assessors appeared to use three different perspectives when interpreting narrative comments, including those of: (i) the student (placing him‐ or herself in the shoes of the student); (ii) the examiner (adopting the role of examiner and reinterpreting comments according to his or her own standards or beliefs), and (iii) the professional (acting as the profession's gatekeeper by considering the assessment to be a representation of real‐life practice).

Conclusions

The present findings add to current understandings of assessors’ interpretations of narrative performance data by identifying the strategies and different perspectives used by expert assessors to frame and bring meaning to written comments. Assessors’ perspectives affect assessors’ interpretations of assessment comments and are likely to be influenced by their beliefs, interpretations of the assessment setting and personal performance theories. These results call for the use of multiple assessors to account for variations in assessor perspectives in the interpretation of narrative assessment data.
Patients with cleft: Experiences, understanding and information provision during treatment
Authors: Abualfaraj Raed J. , Mcdonald Fraser , Daly Blanaid , Scambler Sasha
Published: July 2019

Objective

To explore the knowledge of late adolescent and adults affected with cleft lip and/or palate (CL/P) about their condition and their experiences with information about treatment options and outcomes within the cleft care pathway.

Setting and Sample Population

Twenty‐eight people with CL/P had recently finished or were about to finish their definitive orthodontic/orthognathic (OGN) treatment. Participants were purposively recruited from two cleft centres in the UK.

Materials and Methods

Qualitative, semi‐structured interviews were conducted and all interviews were recorded and transcribed verbatim. Thematic analysis was undertaken using the framework method.

Result

There are a broad range of interpretations and explanations for both the causes and implications of CL/P amongst those living with the condition. This resulted in confusion and left participants vulnerable to misinformation and unable to combat stigma. In addition, there was some confusion about the implication of different treatment options. Participants felt that they did not receive enough information about the nature of the treatment that they would be undergoing and the length and implications of recovery post‐treatment. This was a source of concern for the participants.

Conclusion

The findings of this study suggest that there is a mismatch between the information provided to the families of people with CL/P and the levels of knowledge they have, about both their condition and the treatment options available to them. It is essential that clear, accessible information is provided at the right times in the care pathway to ensure that patients are able to make informed decisions about treatment.
Identification of endogenous small peptides involved in rice immunity through transcriptomics‐ and proteomics‐based screening
Authors: Wang Pingyu , Yao Shaolun , Kosami Ken‐ichi , Guo Ting , Li Jing , Zhang Yuanyuan , Fukao Yoichiro , Kaneko‐Kawano Takako , Zhang Heng , She Yi‐Min , Wang Pengcheng , Xing Weiman , Hanada Kousuke , Liu Renyi , Kawano Yoji
Published: July 2019

Small signalling peptides, generated from larger protein precursors, are important components to orchestrate various plant processes such as development and immune responses. However, small signalling peptides involved in plant immunity remain largely unknown. Here, we developed a pipeline using transcriptomics‐ and proteomics‐based screening to identify putative precursors of small signalling peptides: small secreted proteins (SSPs) in rice, induced by rice blast fungus Magnaporthe oryzae and its elicitor, chitin. We identified 236 SSPs including members of two known small signalling peptide families, namely rapid alkalinization factors and phytosulfokines, as well as many other protein families that are known to be involved in immunity, such as proteinase inhibitors and pathogenesis‐related protein families. We also isolated 52 unannotated SSPs and among them, we found one gene which we named immune response peptide (IRP) that appeared to encode the precursor of a small signalling peptide regulating rice immunity. In rice suspension cells, the expression of IRP was induced by bacterial peptidoglycan and fungal chitin. Overexpression of IRP enhanced the expression of a defence gene, PAL1 and induced the activation of the MAPKs in rice suspension cells. Moreover, the IRP protein level increased in suspension cell medium after chitin treatment. Collectively, we established a simple and efficient pipeline to discover SSP candidates that probably play important roles in rice immunity and identified 52 unannotated SSPs that may be useful for further elucidation of rice immunity. Our method can be applied to identify SSPs that are involved not only in immunity but also in other plant functions.
Process, Theory, and Practice in Direct Democracy: Avenues for New Research
Authors: Cortés Juvenal J.
Published: July 2019

Direct democracy (DD)—including initiatives and referendums—is increasingly used to decide policy around the world. Based on a wide‐ranging review of literature published over the past 25 years, this article offers theoretical and methodological recommendations to advance the study of DD. First, more focus should be placed on the stages of DD and how they affect one another. Richer theories can only flow once the origins, rules, and context of DD are considered—including the endogeneity of DD. Second, a stronger analysis of how DD is justified by democratic theory is needed; I demonstrate that some mechanisms of DD are clearly supported by democratic theory while others lack a coherent foundation. Finally, historical (e.g., ancient Athens) and contemporary DD are often used interchangeably. An overview of past institutions reveals that contemporary DD is not a return to something that once was. Each lesson provides fruitful avenues for future research.

Related Articles

Adams, Brian E. 2012. “Citizens, Interest Groups, and Local Ballot Initiatives.” Politics & Policy 40 (1): 43‐68. https://doi.org/10.1111/j.1747-1346.2011.00336.x

Stephan, Mark. 2004. “Citizens as Representatives: Bridging the Democratic Theory Divides.” Politics & Policy 32 (1): 118‐135. https://doi.org/10.1111/j.1747-1346.2004.tb00178.x

Waheduzzaman, Wahed, and Sharif As‐Saber. 2015. “Politics and Policy in Achieving Participatory Governance in a Developing Country Context.” Politics & Policy 43 (4): 474‐501. https://doi.org/10.1111/polp.12121

Related Media

The Centre for Research on Direct Democracy (C2D). N.d. C2D is a database with information on direct democracy institutions around the globe. http://c2d.ch

LATINNO is the first comprehensive and systematic source of data on new institutions for citizen participation evolving in Latin America. https://www.latinno.net/en/project-information/

The Initiative and Referendum Institute (IRI). N.d. IRI at the University of Southern California tracks all direct democracy mechanisms in the United States. http://www.iandrinstitute.org
Gracilaria phuquocensis sp. nov., a new flattened Gracilaria species (Gracilariales, Rhodophyta), previously recognized as G. mammillaris, from the southern coast of Vietnam
Authors: Le Hau Nhu , Muangmai Narongrit , Kheauthong Sunisa , Sun Zhongmin , Zuccarello Giuseppe C.
Published: July 2019

Flattened Gracilaria species are widely distributed along the coasts of the South China Sea with more than 20 species recorded. Within the South China Sea, Gracilaria mammillaris has only been reported from Vietnam, but this species is likely restricted to the western Atlantic. This study aimed to reevaluate the taxonomic status of Vietnamese specimens of ‘G. mammillaris’ using combined morphological and molecular data. Our data clearly indicated that Vietnamese specimens were morphologically and genetically distinct from authentic G. mammillaris from the western Atlantic, and also other described flat Gracilaria species. We, therefore, propose that specimens from Vietnam originally identified as G. mammillaris be designated as a new species, Gracilaria phuquocensis sp. nov. Morphologically, G. phuquocensis can be distinguished from other flat Gracilaria species by its small thallus size, narrower blades, many medullary layers, abundant basal nutritive filaments within mature cystocarps, and tetrasporangial nemathecium. Our rbcL sequence analyses showed that the new species was sister to Gracilaria rhodymenioides from Thailand, and these two species formed a clade with cylindrical Gracilaria species. Our study contributes to clarification of the taxonomic status of misidentified specimens attributed to the flattened Gracilaria species in the South China Sea.
In‐field classification of herbicide‐resistant Papaver rhoeas and Stellaria media using an imaging sensor of the maximum quantum efficiency of photosystem II
Authors: Linn A I , Mink R , Peteinatos G G , Gerhards R
Published: July 2019

Reliable in‐season and in‐field tools for rapidly quantifying herbicide efficacy in dicotyledonous weeds are missing. In this study, the maximum quantum efficiency of photosystem II (Fv/Fm) of susceptible and resistant Papaver rhoeas and Stellaria media populations in response to treatments with acetolactate synthase (ALS) inhibitors were examined. Seedlings (4–6 leafs) were transplanted into the field immediately after the application of the ALS inhibitors florasulam, metsulfuron‐methyl and tribenuron‐methyl. The Fv/Fm values were assessed 1–7, 9 and 14 days after treatment (DAT). Based on the Fv/Fm values of all fluorescing pixels in the images of herbicide‐treated plants, discriminant maximum‐likelihood classifiers were created. Based on this classifier, an independent set of images were classified into ‘susceptible’ or ‘resistant’ plants. The classifiers’ accuracy, false‐positive rate and false‐negative rate were calculated. The Fv/Fm values of sensitive P. rhoeas and S. media plants decreased within 3 DAT by 28–43%. The Fv/Fm values of the resistant plants of both species were 20% higher than those of the sensitive plants in all herbicide treatments. The classifier separated sensitive and resistant plants 3 DAT with accuracies of 62–100%. False‐positive and false‐negative classifications decreased with increasing DAT. We conclude that by the assessment of the Fv/Fm value in combination with the classification sensitive and resistant P. rhoeas and S. media populations could be separated 3 DAT. This technique can help to select effective control methods and speed up the monitoring process of susceptible and resistant weeds.