bluuebunny/crossref_metadata_2025 huggingface dataset:
Towards understanding the effects of time and emotions on the vacation experience
Authors: Torres Edwin N. , Wei Wei , Hua Nan
Published: October 2017

Purpose

The purpose of this paper is to uncover how emotions change (or remain constant) throughout the course of the vacation experience. Although the importance of affective experiences has been recognized in the literature, the momentary effects of each stage of the vacation on the overall appraisal of the experience deserve more attention.

Design/methodology/approach

A survey instrument was developed using the PANAS scale. Customers were asked for their emotions at different points of their vacation. Data were analysed using multinomial logistic regression, correlations and path analysis.

Findings

The results indicate that it is possible for guests to experience different affective states at different parts of the vacation experience. Furthermore, it is also likely for each service experience to impact the next service, in spite of the apparent distinction between them. Finally, the researchers noted the tendency of consumers to recall mostly positive emotions, thus raising the possibility of various kinds of memory biases in recalling a vacation experience.

Originality/value

Emotions are by their very nature momentary. Consequently, these affective states can change over time, especially over a vacation spanning several days. Therefore, the present research contributes to the literature, in that it measures emotions at various points in time, determines the impact of emotions towards one service provider on the next and ascertains the impact of said emotions on the overall vacation experience.
Herbaceous competition and browsing may induce arrested succession in central European forests
Authors: Thrippleton Timothy , Bugmann Harald , Snell Rebecca S.
Published: October 2017

Arrested succession, that is, an ecosystem permanently halted in an early successional, typically non‐forested state, has been suggested to result from intense competition by understorey vegetation, high browsing pressure and additional disturbances, but the relative importance of these factors is unclear. In addition, distinguishing between permanently arrested succession or merely delayed succession may be highly challenging, if not impossible, due to the large time‐scales involved.

We used the dynamic vegetation model LandClim to systematically explore the effect of multiple factors on delayed and arrested succession over a time span of 1,000 years, starting from an unforested state. We included abiotic and biotic factors as well as large‐scale overstorey disturbance, in four Central European landscapes.

Arrested succession occurred in 1%–14% of the simulations. Among the non‐arrested simulations, 95% reached a forested state (defined as ≥10% canopy cover) within 100 years. Large herbaceous biomass was the most important predictor for arrested succession, followed by browsing and large‐scale disturbances. Combinations of factors were important at particular locations in the landscape, where understorey competition and browsing jointly induced a strong establishment filter. Abiotic conditions consistently influenced the probability of arrested succession, with a low probability under mesic conditions and increased likelihood in more xeric parts of the landscapes.

Synthesis. We demonstrated that permanently arrested succession has the potential to occur in temperate forests, particularly under a combination of high amounts of herbaceous biomass and ungulate browsing in drought‐constrained landscape positions. We thus conclude that considering environmental heterogeneity at the landscape scale is key for understanding the conditions that lead to delayed and arrested succession.
Effect of androgen deprivation therapy on the contractile properties of type I and type II skeletal muscle fibres in men with non‐metastatic prostate cancer
Authors: Lamboley Cedric R , Xu Hongyang , Dutka Travis L , Hanson Erik D , Hayes Alan , Violet John A , Murphy Robyn M , Lamb Graham D
Published: October 2017

The contractile properties of vastus lateralis muscle fibres were examined in prostate cancer (PrCa) patients undergoing androgen deprivation therapy (ADT) and in age‐ and activity‐matched healthy male subjects (Control). Mechanically‐skinned muscle fibres were exposed to a sequence of heavily Ca2+‐buffered solutions at progressively higher free [Ca2+] to determine their force‐Ca2+ relationship. Ca2+‐sensitivity was decreased in both type I and type II muscle fibres of ADT subjects relative to Controls (by −0.05 and −0.04 pCa units, respectively, P < .02), and specific force was around 13% lower in type I fibres of ADT subjects than in Controls (P = .02), whereas there was no significant difference in type II fibres. Treatment with the reducing agent dithiothreitol slightly increased specific force in type I and type II fibres of ADT subjects (by ~2%‐3%, P < .05) but not in Controls. Pure type IIx fibres were found frequently in muscle from ADT subjects but not in Controls, and the overall percentage of myosin heavy chain IIx in muscle samples was 2.5 times higher in ADT subjects (P < .01). The findings suggest that testosterone suppression can negatively impact the contractile properties by (i) reducing Ca2+‐sensitivity in both type I and type II fibres and (ii) reducing maximum specific force in type I fibres.
Governing Towards ‘One Health’: Establishing Knowledge Integration in Global Health Security Governance
Authors: Connolly John
Published: October 2017

Recent global threats (e.g. Ebola, avian influenza, the Zika virus) have demonstrated the need for policy makers to focus on the detection of risks at the animal‐human interface. Yet epistemic knowledge across these domains is not sufficiently joined‐up. The article argues that, despite some progress, in order for the policy agenda for global health security to develop towards a ‘One Health’ model there is a need for integration across public and animal health domains. This article sets out an evaluation framework for establishing knowledge integration across these sectors. The article concludes that although ‘One Health may seem utopian, given there are key challenges when it comes to reaching integration, there are important steps that can be taken the short to medium‐term. These include reforms to education and training programmes and interdisciplinary research collaborations. A key determinant of whether One Health becomes a paradigm which frames public policy, and leads to policy and institutional changes to enable public value creation and sustainability, is the presence of an ‘epistemic community’ that bridges health networks.
The Role of the IMF in Managing the Euro Area Sovereign Debt and Banking Crises: Perspectives from East Asia
Authors: Park Yung Chul
Published: October 2017

This paper analyzes strategies and policy conditionality of the troika – European Commission, European Central Bank, and IMF – in resolving the euro area crisis from Asia's perspective with the 1997 IMF Asian crisis management as a possible counterfactual and a yard stick for their effectiveness. The IMF entered into collaboration with the EU mainly to provide the technical expertise in and share with its European partners the lessons it learned from managing past crises. But many of these lessons have been unheeded – in particular limitations of the export‐led recovery through internal devaluation and the need to move forward with financial reform at an early stage of the crisis and calibrate supply side reform with the implementation capacity of the crisis countries.
ecolottery: Simulating and assessing community assembly with environmental filtering and neutral dynamics inR
Authors: Munoz François , Grenié Matthias , Denelle Pierre , Taudière Adrien , Laroche Fabien , Tucker Caroline , Violle Cyrille
Published: October 2017

We introduce theRpackageecolotterydedicated to quick and efficient simulation of communities undergoing local neutral dynamics with environmentally filtered immigration from a reference species pool (spatially implicit model). The package includes an Approximate Bayesian Computation (ABC) tool to estimate the parameters of these processes. We present the rationale of the approach and show examples of simulations and ABC analysis.

The species in the reference pool differ in their abundances and trait values. Environmental filtering weights the probability of immigration success depending on trait values, while the descendants of established immigrants undergo neutral stochastic drift. The reference pool can be defined in a flexible way as representing, e.g. the composition of a broad biogeographical region, or available dispersers around local communities. The package provides a process‐based alternative to the use of randomization‐based null models.

The package proposes a coalescent‐based simulation algorithm that presents significant advantages over alternative algorithms. It does not require simulating community dynamics from an initial state forward in time but does still allow measurement of the influence of environmental filtering. Because of its high calculation speed, this approach allows simulating many communities within a reasonable amount of time.

Diverse patterns of taxonomic, functional and phylogenetic compositions can be generated. The package can be used to explore the outcome of ecological and evolutionary processes playing at local and regional scales, and to estimate the parameters of these processes based on observed patterns.
Discretionary Accruals: Earnings Management ... or Not?
Authors: Jackson Andrew B.
Published: October 2017

This paper discusses some limitations of discretionary accruals measures. While discretionary accruals are acknowledged to be noisy proxies for earnings management, they are still widely used in the literature. This paper attempts to explain from basic econometrics how discretionary accruals are estimated, and in doing so why they are inappropriate measures for earnings management. It is shown that decisions of peer firms will influence the regression coefficients, and hence residuals, in accruals models, which may lead to false conclusions about earnings management in other firms. This point is emphasized using an artificially constructed firm with no changes in its fundamental performance, and hence no discretion in its accruals. I also note concerns about the inferences, which are commonly not acknowledged in research. Finally, using Accounting and Auditing Enforcement Releases and Enron as examples, I demonstrate how discretionary accruals do not capture what literature often claims.
Cryptomarkets, systemic violence and the ‘gentrification hypothesis’
Authors: Martin James
Published: October 2017

Commentary to: Will growth in cryptomarket drug buying increase the harms of illicit drugs?
Exome Sequencing Identifies a Novel Nonsense Mutation of MYO6 as the Cause of Deafness in a Brazilian Family
Authors: Sampaio‐Silva Juliana , Batissoco Ana Carla , Jesus‐Santos Rafaela , Abath‐Neto Osório , Scarpelli Luciano Cesar , Nishimura Patricia Yoshie , Galindo Layla Testa , Bento Ricardo Ferreira , Oiticica Jeanne , Lezirovitz Karina
Published: October 2017

We investigated 313 unrelated subjects who presented with hearing loss to identify the novel genetic causes of this condition in Brazil. Causative GJB2/GJB6 mutations were found in 12.7% of the patients. Among the familial cases (100/313), four were selected for exome sequencing. In one case, two novel heterozygous variants were found and were predicted to be pathogenic based on bioinformatics tools, that is, p.Ser906* (MYO6) and p.Arg42Cys (GJB3). We confirmed that this nonsense MYO6 mutation segregated with deafness in this family. Only the proband and her unaffected mother exhibited the GJB3 mutation, which is in the same amino acid of a known Erythrokeratodermia variabilis mutation. None of the patients exhibited this skin disease, but the proband exhibited a more severe hearing loss. Hence, the GJB3 mutation was considered to be a variant of uncertain significance. In conclusion, we described a novel nonsense MYO6 mutation that was responsible for the hearing loss in a Brazilian family. This mutation resides in the neck domain of myosin‐VI after the motor domain. Thus, our data give further support for genotype‐phenotype correlations, which state that when the motor domain of the protein is functioning, the hearing loss is milder and has a later onset. The three remaining families without mutations in the known genes suggest that there are still deafness genes to be revealed.
Hyperbaric vs. isobaric bupivacaine for spinal anaesthesia for elective caesarean section: a Cochrane systematic review
Authors: Sng B. L. , Han N. L. R. , Leong W. L. , Sultana R. , Siddiqui F. J. , Assam P. N. , Chan E. S. , Tan K. H. , Sia A. T.
Published: October 2017

Both isobaric and hyperbaric bupivacaine have been used for spinal anaesthesia for elective caesarean section, but it is not clear if one is better than the other. The primary objective of this systematic review was to determine the effectiveness and safety of hyperbaric bupivacaine compared with isobaric bupivacaine administered during spinal anaesthesia for elective caesarean section. We included 10 studies with 614 subjects in the analysis. There was no evidence of differences either in the risk of conversion to general anaesthesia, with a relative risk (95%CI) of 0.33 (0.09–1.17) (very low quality of evidence), or in the need for supplemental analgesia, the relative risk (95%CI) being 0.61 (0.26–1.41) (very low quality of evidence). There was also no evidence of a difference in the use of ephedrine, the amount of ephedrine used, nausea and vomiting, or headache. Hyperbaric bupivacaine took less time to reach a sensory block height of T4, with a mean difference (95%CI) of −1.06 min (−1.80 to −0.31). Due to the rarity of some outcomes, dose variability, use of adjuvant drugs and spinal technique used, future clinical trials should look into using adequate sample size to investigate the primary outcome of the need for supplemental analgesia.
Selenium supplementation during in vitro maturation enhances meiosis and developmental capacity of yak oocytes
Authors: Xiong Xianrong , Lan Daoliang , Li Jian , Lin Yaqiu , Li Mingyang
Published: October 2017

The objectives of the present study were to investigate the effects of selenium (Se) supplementation during in vitro maturation (IVM) on the developmental capacity of yak (Bos grunniens) oocytes. Nuclear maturation, DNA integrity, glutathione peroxidase (GSH‐Px) activity, subsequent embryonic development, and gene expression after in vitro fertilization (IVF) were evaluated. The Se concentrations in yak plasma and follicular fluid were 0.142 and 0.069 μg/mL, respectively. The DNA damage in cumulus cells decreased significantly with 2 and 4 μg/mL supplementation of sodium selenite to IVM medium (P < 0.05). Total GSH‐Px activity in oocytes increased in all Se supplementation groups, and the 2 and 4 μg/mL groups were significantly higher than the control group (0 μg/mL). However, the cleavage rate was not significantly different after Se supplementation (P > 0.05). The IVF blastocyst formation rates of 0, 1 and 4 μg/mL sodium selenite groups were 47.7%, 51.2% and 58.9%, respectively. The 2 μg/mL sodium selenite group had the highest blastocyst formation rate (60.5%). Gene expression analysis revealed that the quantity of transcripts associated with selenoprotein and protein synthesis were high in the 2 and 4 μg/mL groups. In conclusion, both GSH‐Px activity of oocytes and DNA integrity of cumulus cells significantly increased with supplemental Se during oocyte IVM. Considering that embryonic development is responsive to Se supplementation, we inferred that appropriate Se concentrations during IVM were beneficial for yak oocyte maturation and subsequent development.
Vascular plant extinctions in California: A critical assessment
Authors: Rejmánek Marcel
Published: October 2017

Aim

Extinctions of species and subspecific taxa in hotspots of biodiversity deserve special attention. After more than 40 years of major efforts, estimates of extinct plant taxa in California seem to be somewhat stabilized. The time is ripe for an attempt to critically evaluate our current knowledge of plant extinctions in California and make a comparison with other countries with mediterranean‐type climates.

Location

California.

Methods

Besides species‐specific studies and personal communications, major databases and state floras were consulted.

Results

Compared with all numbers published earlier, the current analysis ended with smaller numbers of globally extinct plant species and taxa (13 and 17, respectively) and larger numbers of species and taxa extinct in California, but still present in at least one other state or country (15 and 15). For each species, life form, habitat, year of the last collection and assumed drivers of extinction are listed.

Main conclusions

Most of the presumed extinct taxa were originally present in one or two counties and often are known from only one or a very few collections. Therefore, the most robust generalization regarding factors contributing to taxon extinctions is a small range size and a low original abundance. Most of the presumed globally extinct taxa were originally present in lowlands where most of the human population and habitat destruction are concentrated. Taxa limited to special habitats, like wetlands, seem to be more predisposed to extinction. Among assumed drivers of plant extinction, agriculture, urbanization and development in general are the most often cited possibilities. Compared with other countries with mediterranean‐type climates, the extinction rate of vascular plants in California is lower than in Israel, comparable with the Cape Province of South Africa, Western Australia and continental Mediterranean European countries, and higher than in Chile.
3D printed simulation models based on real patient situations for hands‐on practice
Authors: Kröger E. , Dekiff M. , Dirksen D.
Published: October 2017

During the last few years, the curriculum of many dentistry schools in Germany has been reorganised. Two key aspects of the applied changes are the integration of up‐to‐date teaching methods and the promotion of interdisciplinarity. To support these efforts, an approach to fabricating individualised simulation models for hands‐on courses employing 3D printing is presented. The models are based on real patients, thus providing students a more realistic preparation for real clinical situations. As a wide variety of dental procedures can be implemented, the simulation models can also contribute to a more interdisciplinary dental education. The data used for the construction of the models were acquired by 3D surface scanning. The data were further processed with 3D modelling software. Afterwards, the models were fabricated by 3D printing with the PolyJet technique. Three models serve as examples: a prosthodontic model for training veneer preparation, a conservative model for practicing dental bonding and an interdisciplinary model featuring carious teeth and an insufficient crown. The third model was evaluated in a hands‐on course with 22 fourth‐year dental students. The students answered a questionnaire and gave their personal opinion. Whilst the concept of the model received very positive feedback, some aspects of the implementation were criticised. We discuss these observations and suggest ways for further improvement.
Performance of two different digital evaluation systems used for assessing pre‐clinical dental students’ prosthodontic technical skills
Authors: Gratton D. G. , Kwon S. R. , Blanchette D. R. , Aquilino S. A.
Published: October 2017

Introduction

Proper integration of newly emerging digital assessment tools is a central issue in dental education in an effort to provide more accurate and objective feedback to students. The study examined how the outcomes of students’ tooth preparation were correlated when evaluated using traditional faculty assessment and two types of digital assessment approaches. Specifically, incorporation of the Romexis Compare 2.0 (Compare) and Sirona prepCheck 1.1 (prepCheck) systems was evaluated. Additionally, satisfaction of students based on the type of software was evaluated through a survey.

Material and Methods

Students in a second‐year pre‐clinical prosthodontics course were allocated to either Compare (n = 42) or prepCheck (n = 37) systems. All students received conventional instruction and used their assigned digital system as an additional evaluation tool to aid in assessing their work. Examinations assessed crown preparations of the maxillary right central incisor (#8) and the mandibular left first molar (#19). All submissions were graded by faculty, Compare and prepCheck.

Results

Technical scores did not differ between student groups for any of the assessment approaches. Compare and prepCheck had modest, statistically significant correlations with faculty scores with a minimum correlation of 0.3944 (P = 0.0011) and strong, statistically significant correlations with each other with a minimum correlation of 0.8203 (P < 0.0001). A post‐course student survey found that 55.26% of the students felt unfavourably about learning the digital evaluation protocols. A total of 62.31% felt favourably about the integration of these digital tools into the curriculum.

Conclusions

Comparison of Compare and prepCheck showed no evidence of significant difference in students’ prosthodontics technical performance and perception.
Differential and complementary roles of medial and lateral septum in the orchestration of limbic oscillations and signal integration
Authors: Tsanov Marian
Published: October 2017

Anatomical differences between the medial and lateral septum have associated these nuclei with dissimilar functional roles and behaviours. While the medial septum has been implicated, predominantly, in theta rhythm generation along the septo‐hippocampal axis, the lateral septum has mainly been investigated in the context of septo‐hypothalamic dialogue. Recent advances suggest that medial and lateral septum are more closely functionally related than previously appreciated. Here, we explore the hypothesis that the medial septum mediates ascending septo‐hippocampal theta propagation, while the lateral septum processes a descending hippocampo‐septal and septo‐hypothalamic reinforcement signal that mediates navigation during motivated behaviour. The generation and propagation of theta rhythm are critical for the initiation of exploratory behaviour. Indeed, theta signal processing of medial and lateral septum nuclei may well be involved in the integration of spatial, rewarding and locomotor signals across different brain networks. We review here the structural features, anatomical connectivity and functional properties of the medial and lateral septum. We discuss the heterogeneous anatomy of the lateral septum, which is composed of diverse subregions with distinct ascending and descending projections, and we relate the physiological characteristics of septal nuclei to their functional relationships with the hippocampal formation, the hypothalamus and the brainstem reticular formation during motivated spatial navigation.
The many characters of visual alpha oscillations
Authors: Clayton Michael S. , Yeung Nick , Cohen Kadosh Roi
Published: October 2017

A central feature of human brain activity is the alpha rhythm: a 7–13 Hz oscillation observed most notably over occipitoparietal brain regions during periods of eyes‐closed rest. Alpha oscillations covary with changes in visual processing and have been associated with a broad range of neurocognitive functions. In this article, we review these associations and suggest that alpha oscillations can be thought to exhibit at least five distinct ‘characters’: those of the inhibitor, perceiver, predictor, communicator and stabiliser. In short, while alpha oscillations are strongly associated with reductions in visual attention, they also appear to play important roles in regulating the timing and temporal resolution of perception. Furthermore, alpha oscillations are strongly associated with top‐down control and may facilitate transmission of predictions to visual cortex. This is in addition to promoting communication between frontal and posterior brain regions more generally, as well as maintaining ongoing perceptual states. We discuss why alpha oscillations might associate with such a broad range of cognitive functions and suggest ways in which these diverse associations can be studied experimentally.
Effects of slaking and mechanical breakdown on disaggregation and splash erosion
Authors: Xiao H. , Liu G. , Abd‐Elbasit M. A. M. , Zhang X. C. , Liu P. L. , Zheng F. L. , Zhang J. Q. , Hu F. N.
Published: October 2017

The contributions of different mechanisms of aggregate breakdown to splash erosion are still obscure. This study was designed to investigate the effects of various mechanisms of soil disaggregation on splash erosion. Loamy clay, clay loam and sandy loam soil types were used in this research. Soil aggregate stability was determined by the Le Bissonnais method. Deionized water was used to simulate the combined effect of slaking and mechanical disaggregation, whereas alcohol was used to estimate the contribution of mechanical breakdown only. Simulated rain with an intensity of 60 mm hour−1 was applied at five heights (0.5, 1, 1.5, 2 and 2.5 m) to achieve different amounts of rainfall kinetic energy. The results indicated that the rate of splash erosion increased with the increase in rainfall kinetic energy in tests with both deionized water and alcohol. The rates of splash erosion for three types of soil followed the order of loamy clay soil < clay loam soil < sandy loam soil, but the mean weight diameter (MWD) of disintegrated aggregates followed the reverse order. The rates of splash erosion from the effects of slaking and mechanical breakdown increased with an increase in rainfall kinetic energy. The contributions of slaking and mechanical breakdown to splash erosion decreased for the former, whereas it increased for the latter as rainfall kinetic energy increased. The slaking effect contributed more than 50% of splash erosion. The rates of contribution of slaking and mechanical breakdown to splash erosion depended on rainfall kinetic energy and soil type.

Highlights

Contributions of different mechanisms of aggregate breakdown to splash erosion remain obscure.

Alcohol was used to simulate the effect of mechanical breakdown only.

Slaking contributed more than 50% of splash erosion.

Contributions by mechanisms of aggregate breakdown depend on rainfall kinetic energy and soil type.
Reconciliation and third‐party affiliation in carrion crows
Authors: Sima Miriam Jennifer , Matzinger Theresa , Bugnyar Thomas , Pika Simone
Published: October 2017

Conflicts are costly because they can damage social relationships. To buffer conflicts, various species use post‐conflict behaviour, such as reconciliation or third‐party affiliation. Both behaviours have predominantly been studied in non‐human primates. However, recently, studies revealed post‐conflict behaviour in other mammalian and some bird species (e.g., corvids). While third‐party affiliation has been reported in several corvid species, reconciliation has only rarely been observed. The social structure of the studied groups has been postulated as a reason for the absence of reconciliation. Here, we investigated whether post‐conflict behaviours in corvids indeed mirror the relationship structure. We studied the behaviour of a newly established group of juvenile carrion crows (Corvus corone corone), where pair bonds had not yet been established. We applied a combination of observations and food monopolisation experiments to quantify the use of post‐conflict behaviours. Provisioning food in one or two pieces induced different patterns of aggression during feeding and differently affected the affiliation patterns after feeding. Specifically, victims of severe aggression affiliated with third parties after conflicts in the two‐piece condition, while aggressors affiliated with victims of mild aggression in the one‐piece condition. We thus provide the first evidence that a corvid species, crows, flexibly engage in both third‐party affiliation and reconciliation.
Prospective Parents' Knowledge About Parenting and Their Anticipated Child‐Rearing Decisions
Authors: Powell Darcey N. , Karraker Katherine
Published: October 2017

Objective

To examine whether the theory of planned behavior can be used to understand intentions for child‐rearing practices.

Background

Parenting intentions are formed before becoming a parent, but it is less clear what nonparents' intentions are and how subjective norms, attitudes, and perceived control predict their intentions.

Method

Nonparent emerging adults (N = 353, Mage = 19.6 years, 72% female) were asked about their intentions to (a) breastfeed or support a partner in breastfeeding, (b) circumcise a male infant, (c) co‐sleep, and (4) put their infant in nonparental daytime care. They were also asked what proportion of American parents they thought engaged in each and why they would or would not engage in each practice.

Results

Most intended to breastfeed and to circumcise their male infants, but not to co‐sleep or to put their infant in nonparental daytime care. Participants' inaccurate knowledge about actual parents' behavior (i.e., subjective norms) and the factors that they thought might affect their own future behavior (i.e., attitudes toward and perceived control) were associated with their intentions for the child‐rearing practices.

Conclusion

This study replicated prior research on breastfeeding intentions and extended the viability of the theory of planned behavior to understand prospective parents' intentions for other child‐rearing practices.

Implications

Practitioners should consider discussing the norms surrounding child‐rearing behaviors during health‐ and development‐focused courses in secondary or postsecondary school and with expecting couples.
Exploring Blended Learning in a Postsecondary Spanish Language Program: Observations, Perceptions, and Proficiency Ratings
Authors: Romeo Kenneth , Bernhardt Elizabeth B. , Miano Alice , Leffell Cici Malik
Published: October 2017

Despite the foreign language community's historical interest in employing technology to support language learning, few research studies have linked its use to instructional outcomes and most have failed to address whether technology enhancements lead to increased proficiency gains. This article examines the relationship between technology use and student performance in a Spanish language program at a research university. Through classroom observation and student and instructor self‐reports, coupled with proficiency data from first‐ and second‐year courses, this project investigated the type and distribution of technology use, instructors’ and students’ perceptions of the value of technology use, and the relationship between observed and perceived technology use and the exit proficiency ratings of student participants. The study found that students and instructors used technology to varying degrees and valued different types of technology use in language learning but viewed face‐to‐face communication as most essential. In addition, regardless of very different technology implementations among instructors and courses, students’ proficiency ratings reached the expected exit level for each course and were remarkably consistent among individuals.
Potential pitfalls of aggregating aquatic invertebrate data from multiple agency sources: Implications for detecting aquatic assemblage change across alteration gradients
Authors: Cuffney Thomas F. , Kennen Jonathan G.
Published: October 2017

Data from nine Delaware River basin (DRB) agencies were used to develop procedural steps that harmonise differences in subsample size (organism fixed counts, OFC), taxa identified and lowest taxonomic levels (LTL) used for identifications. These procedural steps are systematically presented to help practitioners avoid some of the pitfalls associated with combining data from multiple agency sources.

Harmonising taxa levels and subsample sizes in the DRB data substantially reduced richness metrics with the majority of the reduction associated with harmonising LTLs rather than OFCs. The opposite was true for abundance metrics with LTLs having little effect and OFCs having a large effect. Harmonisation of LTLs and OFCs increased the average similarity among samples threefold suggesting that failing to harmonise greatly overestimated differences in assemblages among sites.

A hypothetical assemblage in which the abundance of each taxon decreased across a disturbance gradient as a function of published tolerance values was developed from the DRB data. This hypothetical assemblage was used to evaluate how LTLs and OFCs affected responses to disturbance, as indicated by assemblage metrics and ordination analysis, and to evaluate the efficacy of this approach to data harmonisation.

Reducing LTLs (e.g. species to genus) and(or) OFCs (e.g. 300–100) in the hypothetical assemblage reduced measures of taxa richness and made it more difficult to detect responses across the disturbance gradient. Responses of abundance metrics were not affected by LTLs, but were affected by OFCs. More importantly, mixing data with different LTLs and(or) OFCs introduced a second methodological gradient that could be erroneously interpreted as an environmental gradient. The procedures proposed for harmonising LTLs and OFCs were effective at reducing differences and helped to uncover the underlying response of the taxa and assemblage.

Failure to harmonise LTLs and OFCs across mixed data sources can overstate differences among assemblages, reduce the ability to detect underlying environmental gradients and/or introduce methodological gradients that can lead to erroneous interpretations of invertebrate responses to hydrologic alteration or urbanisation. The misinterpretation of underlying environmental gradients can strongly affect the applicability of the findings to support criteria development for aquatic life uses or management actions that strive to balance water availability for human and ecological needs. Consequently, great care must be exercised in harmonising taxa and subsample sizes prior to aggregating data across multiple sources.
Impacts of climate and land use on N2O and CH4 fluxes from tropical ecosystems in the Mt. Kilimanjaro region, Tanzania
Authors: Gütlein Adrian , Gerschlauer Friederike , Kikoti Imani , Kiese Ralf
Published: October 2017

In this study, we quantify the impacts of climate and land use on soil N2O and CH4 fluxes from tropical forest, agroforest, arable and savanna ecosystems in Africa. To do so, we measured greenhouse gases (GHG) fluxes from 12 different ecosystems along climate and land‐use gradients at Mt. Kilimanjaro, combining long‐term in situ chamber and laboratory soil core incubation techniques. Both methods showed similar patterns of GHG exchange. Although there were distinct differences from ecosystem to ecosystem, soils generally functioned as net sources and sinks for N2O and CH4 respectively. N2O emissions correlated positively with soil moisture and total soil nitrogen content. CH4 uptake rates correlated negatively with soil moisture and clay content and positively with SOC. Due to moderate soil moisture contents and the dominance of nitrification in soil N turnover, N2O emissions of tropical montane forests were generally low (<1.2 kg N ha−1 year−1), and it is likely that ecosystem N losses are driven instead by nitrate leaching (~10 kg N ha−1 year−1). Forest soils with well‐aerated litter layers were a significant sink for atmospheric CH4 (up to 4 kg C ha−1 year−1) regardless of low mean annual temperatures at higher elevations. Land‐use intensification significantly increased the soil N2O source strength and significantly decreased the soil CH4 sink. Compared to decreases in aboveground and belowground carbon stocks enhanced soil non‐CO2 GHG emissions following land‐use conversion from tropical forests to homegardens and coffee plantations were only a small factor in the total GHG budget. However, due to lower ecosystem carbon stock changes, enhanced N2O emissions significantly contributed to total GHG emissions following conversion of savanna into grassland and particularly maize. Overall, we found that the protection and sustainable management of aboveground and belowground carbon and nitrogen stocks of agroforestry and arable systems is most crucial for mitigating GHG emissions from land‐use change.
Pediatric Headache and Sleep Disturbance: A Comparison of Diagnostic Groups
Authors: Rabner Jonathan , Kaczynski Karen J. , Simons Laura E. , LeBel Alyssa
Published: October 2017

Objective

To examine whether sleep disturbance differs by headache diagnosis in a pediatric sample, and whether this effect remains when other factors affecting sleep are included.

Background

Primary headache disorders can be severe and disabling, impacting a child's functioning and quality of life. Many children and adolescents with chronic headaches also experience sleep difficulties, and there is likely a bidirectional relationship between headaches and sleep difficulties. Sleep problems may intensify functional and developmental difficulties in youth with chronic headaches. Despite this, research on sleep has largely been conducted only on those with migraines, with a dearth of studies including samples with tension‐type headache (TTH) or new daily persistent‐headache (NDPH).

Methods

This retrospective chart review included 527 patients, ages 7‐17 years, with a primary headache diagnosis of migraine (n = 278), TTH (n = 157), and NDPH (n = 92). Patients completed measures of disability, anxiety, and depression and their parents completed measures of sleep disturbance.

Results

Sleep disturbance was greater in patients with TTH (10.34 ± 5.94, P = .002) and NDPH (11.52 ± 6.40, P < .001) than migraine (8.31 ± 5.89). Across patient groups, greater sleep disturbance was significantly associated with higher levels of functional disability (rs ≥ .16), anxiety (rs ≥ .30), and depression (rs ≥ .32). Additionally, higher pain levels were significantly associated with greater sleep disturbance among TTH patients (r = .23), with this association non‐significant among the other headache groups. When simultaneously examining demographic, pain‐related, and emotional distress factors, older age, higher levels of disability and depression, and NDPH diagnosis were all significant predictors of greater sleep disturbance (r2 = .25).

Conclusions

Assessment and treatment of sleep problems in pediatric patients with chronic headache is important with several contextual and headache diagnostic factors influencing the severity of sleep disturbance.
Consumer health information seeking in social media: a literature review
Authors: Zhao Yuehua , Zhang Jin
Published: October 2017

Objective

The objective of this literature review was to summarise current research regarding how consumers seek health‐related information from social media. Primarily, we hope to reveal characteristics of existing studies investigating the health topics that consumers have discussed in social media, ascertaining the roles social media have played in consumers’ information‐seeking processes and discussing the potential benefits and concerns of accessing consumer health information in social media.

Methods

The Web of Science Core Collection database was searched for existing literature on consumer health information seeking in social media. The search returned 214 articles, of which 21 met the eligibility criteria following review of full‐text documents.

Conclusion

Between 2011 and 2016, twenty‐one studies published explored various topics related to consumer information seeking in social media. These ranged from online discussions on specific diseases (e.g. diabetes) to public health concerns (e.g. pesticide residues). Consumers’ information needs vary depending on the health issues of interest. Benefits of health seeking on social media, in addition to filling a need for health information, include the social and emotional support health consumers gain from peer‐to‐peer interactions. These benefits, however, are tempered by concerns of information quality and authority and lead to decreased consumer engagement.
Effect of peptide–phenolic interaction on the antioxidant capacity of walnut protein hydrolysates
Authors: Su Shiwei , Wan Yangling , Guo Shuntang , Zhang Chao , Zhang Ting , Liang Ming
Published: October 2017

Walnut antioxidant peptides and phenolic compounds (POHs) commonly coexist in walnut protein hydrolysates (WPHs). However, the peptide–phenolic interaction and its effects on antioxidant activities of WPHs remain unknown. Fluorescence and dynamic light scattering were used to study the peptide–phenolic interaction in WPH‐POH mixtures (W‐P) with different POH/WPH ratios; antioxidant abilities of POH only solution, WPH only solution and W‐P were measured with three assays: DPPH radical scavenging, Fe2+ chelation and linoleic acid peroxidation inhibition. Results showed that initially POHs bonded to hydrophobic sites of peptides; subsequently, when POH/WPH ratio exceeded 1:120 (w/w), POHs changed the conformation and average particle size of peptides. Their interaction could at most increase WPHs’ capability in scavenging DPPH radical (44.9%), chelating Fe2+ (36.1%) and inhibiting linoleic acid oxidation (87.5%) at the POH/WPH ratio (w/w) point of 1:12. This research offered a guidance in the production of WPHs with high functionality.
Priority optimization and make‐to‐stock/make‐to‐order decision in multiproduct manufacturing systems
Authors: Hadj Youssef K. , van Delft Ch. , Dallery Y.
Published: October 2017

We consider a single‐stage multiproduct manufacturing facility producing a large number of end products. In order to reduce overall inventory costs, an efficient approach is to produce some items according to a make‐to‐stock (MTS) policy and others according to a make‐to‐order (MTO) policy. Items priority levels play a key role in the optimal MTO/MTS decisions for such typical large‐scale systems. To tackle this issue, the manufacturing facility is modeled as a multiproduct multipriority classes queuing system. We propose a general optimization procedure that selects near‐optimal priority classes, gives the associated flow control mode (MTO or MTS) for each product, and provides a lower bound and an upper bound with respect to the optimal cost. First, we illustrate efficiency of our optimization procedure for this class of nonlinear integer programs via several examples and by a numerical analysis, including a comparison with two alternative heuristics given in the literature. In addition, we provide managerial insights by exhibiting, under various parameter settings, the significant impact of an efficient priority level allocation among items on the inventory costs and on optimal splitting between MTO and MTS products.
Incentive mechanisms for price and advertising coordination in dynamic marketing channels
Authors: Taboubi Sihem
Published: October 2017

This paper examines the issue of price and advertising coordination in bilateral monopolies from a dynamic perspective. Its main objectives are to design incentive mechanisms that the manufacturer can use in order to reduce double marginalization, and to investigate whether these mechanisms can be implemented by the manufacturer and accepted by the retailer. I consider a differential game where a manufacturer controls its wholesale price and its national advertising effort. The carry‐over effects of national advertising build up brand goodwill, which represents the model's state variable. The retailer controls the product's retail price and the local advertising effort, which affect consumer demand, in conjunction with the brand goodwill. I compute strategies and outcomes under three scenarios: (a) a fully coordinated scenario where channel members act as if the channel was vertically integrated; (b) a noncoordinated scenario, considered as the status quo, where the channel is decentralized; and (c) a scenario where incentive mechanisms are offered by the manufacturer. The main results indicate that two incentive mechanisms, namely, a retail‐price incentive and an advertising allowance offered by the manufacturer to the retailer can mitigate the double‐marginalization problem. With these incentives, and an appropriate choice of the channel‐coordinating wholesale price, the manufacturer can induce the retailer to fix its control variables at their channel‐coordinating levels without committing to implement the channel‐coordinating level of national advertising. Our results highlight the role of the channel‐coordinating wholesale price level on the Pareto‐optimality and the implementation of the incentives. I compute the values for the channel‐coordinating wholesale price that can be used as benchmarks by channel members in order to evaluate if the incentives should be implemented or not. I illustrate our results with numerical simulations indicating the channel‐coordinating wholesale price values where we observe an increase in both channel members' individual profits when the incentives are implemented (i.e., with respect to the status quo). These results can be explained by the decrease in retail price and the increase in local and national advertising. Both effects explain the increase in brand goodwill and demand when the incentives are implemented.
Dense nanocrystalline UO2+x fuel pellets synthesized by high pressure spark plasma sintering
Authors: Yao Tiankai , Scott Spencer M. , Xin Guoqing , Gong Bowen , Lian Jie
Published: October 2017

Nanocrystalline UO2+x powders are prepared by high‐energy ball milling and subsequently consolidated into dense fuel pellets (>95% of theoretical density) under high pressure (750 MPa) by spark plasma sintering at low sintering temperatures (600°C‐700°C). The grain size achieved in the dense nano‐ceramic pellets varies within 60‐160 nm as controlled by sintering temperature and duration. The sintered fuel pellets are single phase UO2+x with hyper‐stoichiometric compositions as derived by X‐ray diffraction, and micro‐Raman measurements indicate that random oxygen interstitials and Willis clusters dominate the single phase nano‐sized oxide pellets of UO2.03 and UO2.11, respectively. The thermal conductivities of the densified nano‐sized oxide fuel pellets are measured by laser flash, and the fuel stoichiometry displays a dominant effect in controlling thermal transport properties. A reduction in thermal conductivity is also observed for the dense nano‐sized pellets as compared with micron‐sized counterparts reported in the literature. The correlation among the SPS sintering parameters—microstructure control—properties is established, and the nano‐sized UO2+x pellets with controlled microstructure can serve as the model systems for fundamental understandings of fuel behaviors and obtaining critical experimental data for multi‐physics MARMOT model validation.