bluuebunny/crossref_metadata_2025 huggingface dataset:
Do farmers exhibit disposition effect? Evidence from grain markets
Authors: L. Mattos Fabio , A. Fryza Stefanie
Published: April 2014

Purpose

– The purpose of this paper is to explore the existence of disposition effect among Canadian wheat farmers when marketing their grain. This study examines the question of whether farmers wait too long to price their grain or whether they price it too soon.

Design/methodology/approach

– The disposition effect is a common behavior documented in financial markets, and reflects the notion that investors tend to hold losing positions too long and close winning positions too fast. This idea can also be applied to grain marketing, exploring whether farmers sell their grain more readily when prices are “high” and wait longer when prices are “low.” Based on the approach by Odean (1998), marketing strategies of 15,564 farmers between 2003/2004 and 2008/2009 are examined.

Findings

– Results support the existence of disposition effect in marketing decisions. Farmers seem to be eager to sell when prices offered by contracts are above their reference price and wait longer to sell when prices offered by contracts are below their reference price. There is no clear evidence that farmers might consistently benefit from this behavior. On the other hand, it is not clear whether this behavior can be costly to farmers.

Originality/value

– Exploring the existence of disposition effect is relevant because this behavior can affect performance. If grain is sold too early, farmers can miss opportunities to sell at higher prices later. If grain is held too long, prices can go down and farmers will end up selling at lower prices. This study uses unique data to perform the first analysis of the disposition effect in the agricultural industry, and its findings can provide new insights and move us toward a more complete understanding of decision making in this industry.
The wealth effects of accelerated stock repurchases
Authors: C. Yook Ken , Gangopadhyay Partha
Published: April 2014

Purpose

– The wealth effect of accelerated stock repurchase (ASR) documented by previous studies is not as large as the authors would have expected. The authors believe that there are potentially important sampling problems in the previous studies, which make the results less reliable. Identifying a number of factors that can possibly affect the announcement-period returns, the purpose of this paper is to reexamine the wealth effect of ASRs.

Design/methodology/approach

– The paper identifies a number of factors that can possibly affect the announcement-period returns to ASRs which include: whether an ASR announcement in the press is the initiation date or the completion date of the ASR; the size of the ASR program; whether an ASR is part of an open market repurchase (OMR) program; the frequency of ASR announcements by a firm; whether other corporate news is announced simultaneously with an ASR. The paper partitions the ASR sample into three groups, and then examines the wealth effect of these groups.

Findings

– The empirical results show that the market reacts differently to the announcement of ASR in these three groups. The three-day announcement-period CAR (t=−1, +1) is 3.59 percent for the high-wealth-effect group, 2.01 percent for the medium-wealth-effect group, and 1.48 percent for the low-wealth-effect group. The paper also identifies the size of the ASR program, whether the ASR is announced simultaneously with an OMR or not, and the frequency of ASR announcements are the most important determinants of the announcement-period abnormal returns.

Originality/value

– These findings suggest that the weaker wealth effects of ASRs that have been documented in previous studies are due to sampling related issues.
Stress and Burnout in Bicultural Teams in Hi‐tech Industry
Authors: Pines Ayala Malach , Zaidman Nurit
Published: May 2014

This study examined burnout, stress and work importance among 120 Israelis working in binational teams, using quantitative (questionnaire) and qualitative (semi‐structured interview) methodologies. Based on the existential perspective, the study documented low levels of burnout despite high levels of stress, which were explained by the high perceived importance of the work. Hierarchical regression showed that importance moderated the effect of stress on burnout. Findings also revealed that the unexpected social stressors associated with cultural differences between team members were more stressful than the stressors associated with high‐tech work.
Encountering nature through fieldwork: expert knowledge, modes of reasoning, and local creativity
Authors: Rival Laura
Published: April 2014

The concept of ‘relation’ has been central to the anthropological reworking of the nature/culture and nature/society dichotomies. However, ecology is relational in a way that has often been ignored or dismissed in contemporary socio‐cultural anthropology. This article shows that there is more to ethnoecology than an ethnocentric form of analysis representing other people's understandings of the natural world through the prejudiced lens of Western scientific classifications. Three ‘fieldwork on fieldwork’ experiments involving encounters between natural scientists and indigenous communities inAmazonianEcuador andSouthernGuyana are discussed to illustrate the heterogeneity of human knowledge, the role of expert knowledge in intercultural communication, and the need to differentiate ecological reasoning from moral reasoning.
Impact of a premature menopause on cognitive function in later life
Authors: Ryan J , Scali J , Carrière I , Amieva H , Rouaud O , Berr C , Ritchie K , Ancelin M‐L
Published: April 2014

Objective

To determine whether premature menopause (≤40 years) can have long‐lasting effects on later‐life cognition and investigate whether this association varies depending on the type of menopause and use of hormone treatment (HT).

Design

Population‐based cohort study.

Setting

The French Three‐City Study.

Population

Four thousand eight hundred and sixty‐eight women aged at least 65 years.

Methods

Multivariable‐adjusted logistic regression models were used to determine the association between age at menopause, type of menopause (surgical, natural), and the use of menopausal HT and later‐life cognitive function.

Main outcome measures

Performance on a cognitive test battery (at baseline and over 7 years) and clinical dementia diagnosis.

Results

Menopause at or before the age of 40 years, both premature bilateral ovariectomy and premature ovarian failure (non‐surgical loss of ovarian function), was associated with worse verbal fluency (OR 1.56, 95%CI 1.12–1.87, P = 0.004) and visual memory (OR 1.39, 95%CI 1.09–1.77, P = 0.007) in later life. HT at the time of premature menopause appeared beneficial for later‐life visual memory but increased the risk of poor verbal fluency. Type of menopause was not significantly associated with cognitive function. Premature menopause was associated with a 30% increased risk of decline in psychomotor speed and global cognitive function over 7 years.

Conclusion

Both premature surgical menopause and premature ovarian failure were associated with long‐term negative effects on cognitive function, which are not entirely offset by menopausal HT. In terms of surgical menopause, these results suggest that the potential long‐term effects on cognitive function should form part of the risk/benefit ratio when considering ovariectomy in younger women.
Determinants of Coverage Decisions in Health Insurance Marketplaces: Consumers' Decision‐Making Abilities and the Amount of Information in Their Choice Environment
Authors: Barnes Andrew J. , Hanoch Yaniv , Rice Thomas
Published: April 2014

Objective

To investigate the determinants and quality of coverage decisions among uninsured choosing plans in a hypothetical health insurance marketplace.

Study Setting

Two samples of uninsured individuals: one from an Internet‐based sample comprised largely of young, healthy, tech‐savvy individuals (n = 276), and the other from low‐income, rural Virginians (n = 161).

Study Design

We assessed whether health insurance comprehension, numeracy, choice consistency, and the number of plan choices were associated with participants' ability to choose a cost‐minimizing plan, given their expected health care needs (defined as choosing a plan costing no more than $500 in excess of the total estimated annual costs of the cheapest plan available).

Data Collection

Primary data were collected using an online questionnaire.

Principal Findings

Uninsured who were more numerate showed higher health insurance comprehension; those with more health insurance comprehension made choices of health insurance plans more consistent with their stated preferences; and those who made choices more concordant with their stated preferences were less likely to choose a plan that cost more than $500 in excess of the cheapest plan available.

Conclusions

Increasing health insurance comprehension and designing exchanges to facilitate plan comparison will be critical to ensuring the success of health insurance marketplaces.
Estimation of linkage disequilibrium and interspecific gene flow in Ficedula flycatchers by a newly developed 50k single‐nucleotide polymorphism array
Authors: Kawakami Takeshi , Backström Niclas , Burri Reto , Husby Arild , Olason Pall , Rice Amber M. , Ålund Murielle , Qvarnström Anna , Ellegren Hans
Published: April 2014

With the access to draft genome sequence assemblies and whole‐genome resequencing data from population samples, molecular ecology studies will be able to take truly genome‐wide approaches. This now applies to an avian model system in ecological and evolutionary research: Old World flycatchers of the genus Ficedula, for which we recently obtained a 1.1 Gb collared flycatcher genome assembly and identified 13 million single‐nucleotide polymorphism (SNP)s in population resequencing of this species and its sister species, pied flycatcher. Here, we developed a custom 50K Illumina iSelect flycatcher SNP array with markers covering 30 autosomes and the Z chromosome. Using a number of selection criteria for inclusion in the array, both genotyping success rate and polymorphism information content (mean marker heterozygosity = 0.41) were high. We used the array to assess linkage disequilibrium (LD) and hybridization in flycatchers. Linkage disequilibrium declined quickly to the background level at an average distance of 17 kb, but the extent of LD varied markedly within the genome and was more than 10‐fold higher in ‘genomic islands’ of differentiation than in the rest of the genome. Genetic ancestry analysis identified 33 F1 hybrids but no later‐generation hybrids from sympatric populations of collared flycatchers and pied flycatchers, contradicting earlier reports of backcrosses identified from much fewer number of markers. With an estimated divergence time as recently as <1 Ma, this suggests strong selection against F1 hybrids and unusually rapid evolution of reproductive incompatibility in an avian system.
Interspecific variation in large mammal responses to human observers along a conservation gradient with variable hunting pressure
Authors: Kiffner C. , Kioko J. , Kissui B. , Painter C. , Serota M. , White C. , Yager P.
Published: April 2014

When subject to anthropogenic hunting risks, wildlife populations may adjust their anti‐predator behaviour; however, such plastic response has rarely been assessed. We assessed the response of eight species (African elephant,Maasai giraffe, plains zebra, common wildebeest,Grant's gazelle, impala,Thomson's gazelle andKirk's dik dik) towards human observers in a landscape with variable anthropogenic hunting pressure. Using logistic regressions, we tested the effect of habitat type, group size, distance to observer and conservation status of the area on the likelihood of animal behavioural adjustments (walking away, fleeing or giving alarm calls). Habitat type did not affect the likelihood of a response towards humans. Dik diks were less likely to respond towards human when they were in larger groups. In contrast, zebras and Thomson's gazelles were marginally significantly more likely to show a response when in larger groups. Responses of all species were significantly or marginally significantly (elephant) lower with increasing distance from observers (an increase by one meter distance changed the response likelihood by 0.01–0.30). Four species (zebra, wildebeest, impala, dik dik) showed a gradual adjustment of responsiveness according to conservation status and were most responsive in non‐protected and least responsive in fully protected areas (0.02–0.29 times less responsive in fully vs. multiple‐use areas). However, elephants, giraffes and both gazelle species did not significantly adjust their behaviour according to conservation status. This suggests that the behaviour of some species can be used as useful indicator of conservation status of an area whereas the behaviour of other species does not allow discriminating between management types. More generally, our study highlights the importance of assessing and controlling illegal hunting in multiple‐use areas and suggests a stronger consideration of human‐induced risk effects in the conservation of ungulates.
Annual cycle of nest composition in the queen‐dimorphic weaver antPolyrhachis australis Mayr, 1870 (Hymenoptera:Formicidae) in northernQueensland
Authors: Downes Michael F
Published: April 2014

TheAustralian spiny weaver antPolyrhachis australis Mayr, 1870 is an arboreal formicine ant that constructs nests using silk and particulate matter (carton). BetweenSeptember 2009 andDecember 2012, the contents of 181P. australisnests were recorded. Of these, 14% were queenless, 21% were monogynous and 65% were polygynous. Monogynous nests had more than double the number of brood per queen, but were outnumbered nine to one by polygynous nests inJanuary, just after the reproductive phase and before the heaviest rain of the wet season. This proportion fell close to equal before the start of the next reproductive phase inSeptember, suggesting attrition of queens by competition during the ergonomic phase of the annual cycle that peaks inMay. The reproductive phase of the annual cycle started with the appearance of new gynes inSeptember throughNovember. Male production increased inOctober, peaked inNovember andDecember, and declined inJanuary. Hence, gynes were produced before males (protogyny). The pupal sex ratio was heavily male‐biased during this time. Males continued to be produced in relatively low numbers throughout the year, supporting (along with other evidence including nest‐size limiting habitat structure) the view thatP. australiscolonies are polygynous and polydomous. The polygynous status of most nests may have arisen more from retention of queens in the mother nest than from adoption. Queen size was bimodal and the microgyne–macrogyne dimorphism may point to a mixed strategy of nest/colony founding whereby macrogynes typically fly and establish colonies independently, while microgynes typically walk to new nest sites and found nests dependently under the protection of a retinue of workers. In support of this inference, all of 49 queens which displayed brachyptery or other wing malformations were microgynes.
Detection rate and outcome of colonic serrated epithelial changes in patients with ulcerative colitis or Crohn's colitis
Authors: Johnson D. H. , Khanna S. , Smyrk T. C. , Loftus E. V. , Anderson K. S. , Mahoney D. W. , Ahlquist D. A. , Kisiel J. B.
Published: April 2014

Background

Chronic ulcerative colitis (CUC) and colonic Crohn's disease (CD) increase colorectal neoplasia (CRN) risk. While sessile serrated polyp (SSP) is a known cancer precursor, serrated epithelial changes (SEC) are of uncertain prevalence and neoplastic risk.

Aim

To assess the serrated lesion detection rates in CUC and CD and documented incidence of subsequent CRN in a retrospective, single‐centre cohort study.

Methods

Patients were identified by a central diagnostic index and pathology review confirmed SEC, SSP, CUC and CD diagnoses from 2006–12. Matched controls were identified from among all CUC and CD patients having colonoscopy during the second half of the time period. All were followed for incident CRN, estimated by the Kaplan–Meier method.

Results

Between 2006 and 2012, 79 SEC and 10 SSP cases were identified. Detection rates were estimated to be 10/1000 and 2/1000 patients, for SEC and SSP respectively, among 4208 unique CUC or CD patients having colonoscopy from 2010–12. With only 10 cases, SSP patients were not further analysed. Cumulative incidence of subsequent CRN at 1 and 3 years was 12% (95% CI, 0–30%) and 30% (3–57%), respectively, in SEC patients compared to 4% (0–12%) and 9% (0–23%), respectively, in CUC or CD controls (P = 0.047, log‐rank). However, this statistical difference was not significant after patients were stratified for history of prior or synchronous dysplasia (P = 0.09).

Conclusions

Serrated epithelial changes and sessile serrated polyps are uncommonly detected by colonoscopy in chronic ulcerative colitis and Crohn's disease patients. Histology with changes of serrated epithelium may be associated with risk of subsequent colorectal neoplasia, however further studies are needed to explore this relationship.
Technology use and learning characteristics of students in higher education: Do generational differences exist?
Authors: Lai Kwok‐Wing , Hong Kian‐Sam
Published: May 2014

As digital technologies form an inextricable part of young people's everyday lives, some commentators claim that the current generation of learners think and learn differently from their predecessors. This study investigated the validity of this claim by surveying 799 undergraduate and 81 postgraduate students at a large research‐intensive university in New Zealand to document their use of digital technologies on university and social activities and comparing three age groups of students (under 20, 20–30 and over 30) to see whether there were any differences in their learning characteristics. The findings of the study showed that while students spent a large amount of time on digital technologies, the range of digital technologies they used was rather limited. There were also no practical generational differences in the technology use pattern and learning characteristics found in this study. The results of this study suggest that generation is not a determining factor in students' use of digital technologies for learning nor has generation had a radical impact on learning characteristics of higher education students.
Therapeutic targeting of the mTOR‐signalling pathway in cancer: benefits and limitations
Authors: Moschetta M , Reale A , Marasco C , Vacca A , Carratù M R
Published: April 2014

The mammalian target of rapamycin (mTOR) plays an important role in the regulation of protein translation, cell growth and metabolism. The mTOR protein forms two distinct multi‐subunit complexes: mTORC1 and mTORC2. The mTORC1 complex is activated by diverse stimuli, such as growth factors, nutrients, energy and stress signals; and essential signalling pathways, such as PI3K and MAPK, in order to control cell growth, proliferation and survival. mTORC1 also activates S6K1 and 4EBP1, which are involved in mRNA translation. The mTORC2 complex is resistant to rapamycin inhibitory activity and is generally insensitive to nutrient‐ and energy‐dependent signals. It activates PKC‐α and Akt and regulates the actin cytoskeleton. Deregulation of the mTOR‐signalling pathway (PI3K amplification/mutation, PTEN loss of function, Akt overexpression, and S6K1, 4EBP1 and eIF4E overexpression) is common in cancer, and alterations in components of the mTOR pathway have a major role in tumour progression. Therefore, mTOR is an appealing therapeutic target in many tumours. Here we summarize the upstream regulators and downstream effectors of the mTORC1 and mTORC2 pathways, the role of mTOR in cancer, and the potential therapeutic values and issues related to the novel agents targeting the mTOR‐signalling pathway.
Linking Land‐Use Scenarios, Remote Sensing and Monitoring to Project Impact of Management Decisions
Authors: Farwig Nina , Lung Tobias , Schaab Gertrud , Böhning‐Gaese Katrin
Published: April 2014

Large‐scale modifications of natural ecosystems lead to mosaics of natural, semi‐natural and intensively used habitats. To improve communication in conservation planning, managers and other stakeholders need spatially explicit projections at the landscape scale of future biodiversity under different land‐use scenarios. For that purpose, we visualized the potential effect of five forest management scenarios on the avifauna of Kakamega Forest, western Kenya using different measures of bird diversity and GIS data. Future projections of bird diversity combined: (1) remotely sensed data on the spatial distribution of different forest management types; (2) field‐based data on the biodiversity of birds in the different management types; and (3) forest management scenarios that took into account possible views of various stakeholder groups. Management scenarios based on the species richness of forest specialists were very informative, because they reflected differences in the proportions of near‐natural forest types among the five scenarios. Projections based on community composition were even more meaningful, as they mirrored not only the proportions of near‐natural forest types, but also their perimeter to area ratios. This highlights that it is important to differentiate effects of the total area of available habitat and the degree of habitat fragmentation, both for species richness and community composition. Furthermore, our study shows that an approach that combines land‐use scenarios, remote sensing and field data on biodiversity can be used to visualize future biodiversity. As such, visualizations of alternative scenarios are valuable for successful communication about conservation planning considering different groups of stakeholders in species‐rich tropical forests.
Mutations in POT1 predispose to familial cutaneous malignant melanoma
Authors: Trigueros‐Motos L.
Published: April 2014

POT1 loss‐of‐function variants predispose to familial melanoma

Robles‐Espinoza et al. (2014)

Nat Genet 46(5):478–481

Rare missense variants in POT1 predispose to familial cutaneous malignant melanoma

Shi et al. (2014)

Nat Genet 46(5):482–486
Genotyping of high‐risk human papillomaviruses in p16/Ki‐67‐positive urothelial carcinoma cells: even a worm will turn
Authors: Advenier A.‐S. , Casalegno J.‐S. , Mekki Y. , Decaussin‐Petrucci M. , Mège‐Lechevallier F. , Ruffion A. , Piaton E.
Published: May 2014

Objective

Co‐expression of p16INK4a protein and Ki‐67 (p16/Ki‐67) is noted in almost all high‐grade urothelial lesions. However, the aetiological role or, conversely, the absence of causative effect of high‐risk human papillomaviruses (hr‐HPVs) has not been documented. The purpose of this study is to evaluate HPV DNA in p16/Ki‐67‐positive, high‐grade urothelial tumour cells.

Methods

Fifty‐seven urine samples collected from 50 patients, including 55 histologically proven high‐grade proliferations and two cases with clinical evidence of malignancy, were analysed for p16/Ki‐67. Immunolabelling was performed in destained Papanicolaou‐stained slides after ThinPrep® processing. HPV genotyping was performed by polymerase chain reaction (PCR) using a DNA microarray for 35 HPV types. Confirmation of the presence (or absence) of HPV in tissue samples was verified using a reasoned approach combining PCR and in situ hybridization (ISH) for hr‐HPVs.

Results

Co‐expression of p16/Ki‐67 was noted in 43 of 57 (75.4%) cases. In these, hr‐HPVs 16, 31 and 70, and low risk HPV 84, were detected in the urine in four patients (8%). Upregulation of p16INK4a protein was confirmed on bladder biopsy or transurethral resection specimens, but PCR and ISH for hr‐HPVs were both negative on the tissue sections.

Conclusion

Our results show a low prevalence of HPV infection in the urinary tract of patients with p16/Ki‐67‐positive urothelial malignancy. The study confirms that the deregulated cell cycle, as demonstrated by p16/Ki‐67 dual labelling, is independent of the oncogenic action of hr‐HPVs in high‐grade urothelial proliferations.
Parabiotic ants: the costs and benefits of symbiosis
Authors: MENZEL FLORIAN , KRIESELL HANNAH , WITTE VOLKER
Published: April 2014

1. Mutualisms are important drivers of co‐evolution and speciation. However, they typically imply costs for one or both partners. Each partner consequently tries to maximise benefits and minimise costs. Mutualisms can therefore develop towards commensalism or parasitism if one partner fails to provide sufficient benefits. This is particularly likely in diffuse interactions, where multiple species can associate with each other. If costs and benefits of a species vary with the identity of the partner species, this may result in a geographical mosaic of co‐evolution.

2. In the present study, inter‐specific interactions in two parabiotic associations of ants were studied (Hymenoptera: Formicidae). One Crematogaster species was associated with one of two closely related Camponotus species. We assessed cost and benefits by studying behavioural interactions, foraging behaviour, and nest defence in the associations.

3. While parabioses had been shown to be mutualistic, evidence was found for exploitation and aggressive competition between species. In spite of apparent costs of being exploited, we found no benefits for one partner (Crematogaster). The magnitude of potential costs to Crematogaster varied between the two Camponotus species.

4. We conclude that the cost/benefit ratio for Crematogaster varies between the two Camponotus partners, and between environmental conditions. Parabiosis can thus fluctuate between mutualism, commensalism, and parasitism, with Crematogaster being the species that may have higher costs than benefits.

5. We suggest that geneflow in the Crematogaster population hinders local adaptation to the resulting mosaic of locally varying selection pressures. This study demonstrates how diffuse interactions and environmental variation can result in a complex of local selection pressures.
Corrigendum to Ferguson and Ponciano ()
Authors: Ferguson Jake M. , Ponciano Jose M.
Published: May 2014

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[¹²³I]FP‐CIT SPECT (DaTSCAN) may be a useful tool to differentiate between Parkinson's disease and vascular or drug‐induced parkinsonisms: a meta‐analysis
Authors: Brigo F. , Matinella A. , Erro R. , Tinazzi M.
Published: April 2014

Background and purpose

Differentiating idiopathic Parkinson's disease from secondary parkinsonian syndromes is crucial since their management and prognosis differ considerably. Functional imaging of the dopaminergic pathway by means of [¹²³I]FP‐CIT SPECT (DaTSCAN) might be useful in this regard, but its role is still controversial. The accuracy of DaTSCAN in the differential diagnosis between Parkinson's disease and vascular or drug‐induced parkinsonism was therefore systematically reviewed.

Methods

MEDLINE and CENTRAL were searched for studies aiming to determine accuracy measures (sensitivity, specificity, diagnostic odds ratio, positive and negative likelihood ratios) of DaTSCAN in differentiating between Parkinson's disease and vascular or drug‐induced parkinsonism.

Results

Five studies were included. Pooled accuracy measures in differentiating between Parkinson's disease and vascular or drug‐induced parkinsonism were relatively high, with sensitivity and specificity values above 85% and 80%, respectively.

Conclusions

DaTSCAN might accurately differentiate between early Parkinson's disease and secondary parkinsonian conditions, namely vascular or drug‐induced, in patients with clinically unclear parkinsonism. However, all the studies reviewed here show several methodological limits, which prevent definitive conclusions on the role of DaTSCAN being drawn in this context. Further studies are needed to confirm our results and definitely evaluate the utility of DaTSCAN in differentiating between Parkinson's disease and vascular or drug‐induced parkinsonism.
Early‐onset Alzheimer's disease: a global cross‐sectional analysis
Authors: Panegyres P. K. , Chen H. Y. ,   the Coalition against Major Diseases (CAMD)
Published: April 2014

Background and purpose

Little is known about factors associated with early‐onset Alzheimer's disease (EOAD), which occurs before 65 years of age. The identification of factors of EOAD might provide insights into Alzheimer's disease (AD) pathogenesis.

Methods

Data from over 3000 subjects with AD from C‐Path Online Data Repository were used to compare demographics, comorbidities and prescribed medications between EOAD and late‐onset Alzheimer's disease (LOAD). The generalized estimating equations binomial model was used to identify factors associated with EOAD, allowing for within‐trials correlation (multiple patients from one single trial).

Results

Despite the similar proportions in White, Asian and Black between EOAD and LOAD, a significantly higher proportion of EOAD population was from other races: Native American Indian, Alaskan and Hawaiian and other minorities (including Hispanics) (P < 0.0001); and were more likely to have anxiety or depression (P < 0.0001). A high proportion of the LOAD population reported a history of AD from any relative (70% vs. 58%); atrial fibrillation, hypertension, heart disease, stroke, hypercholesterolaemia and hypothyroidism were over‐represented in LOAD (P < 0.01). LOAD patients used more risperidone and donepezil (P < 0.01). The multivariable model results showed that, compared with LOAD, EOAD patients were more frequently from other races and were more likely to have anxiety or depression, with less hypertension, stroke and atrial fibrillation.

Conclusion

Early‐onset Alzheimer's disease is found more frequently in Native American Indians, Alaskans, Hawaiians and other minorities, including Hispanics; patients with EOAD have more anxiety or depression. EOAD occurs independently of hypertension, stroke and atrial fibrillation.
Structure of the iron‐free true C‐terminal half of bovine lactoferrin produced by tryptic digestion and its functional significance in the gut
Authors: Rastogi Nilisha , Singh Avinash , Pandey Sada Nand , Sinha Mau , Bhushan Asha , Kaur Punit , Sharma Sujata , Singh Tej P.
Published: May 2014

Bovine lactoferrin, a 76‐kDa glycoprotein (Ala1–Arg689) consists of two similar N‐ and C‐terminal molecular halves with the ability to bind two Fe3+ ions. The N‐terminal half, designated as the N‐lobe (Ala1–Arg341) and the C‐terminal half designated as the C‐lobe (Tyr342–Arg689) have similar iron‐binding properties, but the resistant C‐lobe prolongs the physiological role of bovine lactoferrin in the digestive tract. Here, we report the crystal structure of true C‐lobe, which was produced by limited proteolysis of bovine lactoferrin using trypsin. In the first proteolysis step, two fragments of 21 kDa (Glu86–Lys282) and 45 kDa (Ser283–Arg689) were generated because two lysine residues, Lys85 and Lys282, in the structure of iron‐saturated bovine lactoferrin were fully exposed. The 45‐kDa fragment was further digested at the newly exposed side chain of Arg341, generating a 38‐kDa perfect C‐lobe (Tyr342–Arg689). By contrast, the apo‐lactoferrin was cut by trypsin only at Arg341, which was exposed in the structure of apo‐lactoferrin, whereas the other two sites with Lys85 and Lys282 are inaccessible. The purified iron‐saturated C‐lobe was crystallized at pH 4.0. The structure was determined by the molecular replacement method using coordinates of the C‐terminal half (Arg342–Arg689) of intact camel apo‐lactoferrin. The structure determination revealed that the iron atom was absent and the iron‐binding cleft was found in a wide‐open conformation, whereas in the previously determined structure of iron‐saturated C‐lobe of bovine lactoferrin, the iron atom was present and the iron‐binding site was in the closed confirmation.

Structured digital abstract

 trypsin cleaves lactoferrin by enzymatic study (
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Fatigue crack growth analysis of a reinforced cylindrical shell under random loading
Authors: Salari M. , Shahani A. R. , Moayeri Kashani H.
Published: April 2014

In this paper, fatigue crack growth analysis and reliability evaluation of a reinforced cylindrical shell subjected to random loading have been studied. At first, random loading is extracted from an experimentally obtained power spectral density curve. Then, stress analysis of the shell is carried out using Abaqus® (ABAQUS Inc., Palo Alto, CA, USA) standard code with the aid of a shell‐to‐solid submodelling technique, and the critical positions susceptible of crack nucleation are determined. Then, the fatigue crack propagation is simulated three‐dimensionally in these regions using the Zencrack® software (Zentech International Ltd, London, UK), and the fatigue life and reliability are calculated using the central limit theory. For the evaluation of fatigue life of the full‐scale structure, a procedure of fatigue crack growth and linking up of the two adjacent cracks emanating from critical rivet holes is outlined under random cyclic loading. Using stochastic analysis, closed‐form relations are derived for the probability of failure and reliability.
Taguchi sensitivity analysis of damage parameters for predicting the damage Mechanism of 9Cr steel under low‐cycle fatigue test
Authors: Hormozi R. , Biglari F. , Nikbin K.
Published: April 2014

Numerical investigations of low‐cycle fatigue damage parameters of a 9Cr steel have been studied and compared with the previous results in order to understand the effect of the damage parameters on predicting the damage development of the material. Using the nonlinear kinematic softening criterion, the Chaboche constitutive equation is combined with the hysteresis total stress–strain energy concept to implement damage initiation and evolution; the remaining life of the specimen can be predicted. In this paper, the cyclic softening model in conjunction with the progressive damage evolution model successfully predicted the failure times of the experimental tests. By using a novel sensitivity analysis of the damage parameters c1, c2, c3 and c4 based on the Taguchi method, the highest parameter effect has been determined.
Fisheries management scenarios: trade‐offs between economic and biological objectives
Authors: Maravelias C. D. , Pantazi M. , Maynou F.
Published: April 2014

An age‐structured, population biology submodel and an economic submodel with vessel‐specific dynamics were applied to a demersal fishery in the North Aegean (NE Mediterranean) that consists of three main stocks: European hake Merluccius merluccius (L.), red mullet Mullus barbatus L. and striped red mullet Mullus surmuletus L. The Mefisto model is a bioeconomic simulation model through which the biological and economic submodels (disaggregated at the vessel level) are linked by means of a fishing mortality vector. Alternative management scenarios were built and tested based on input controls, and the performance of these strategies was examined against those of current policies. Three alternative management strategies were as follows: (1) reducing the coastal fisheries' fleet units; (2) limiting the effort level (days at sea) of the trawl fleets; and (3) changing the selectivity patterns of the trawl by increasing mesh size. The results show that for all three species, any of the three management measures (input controls) would be beneficial to both the stock and the fleets (over the medium and long terms) compared with the projections over time for the status quo. Improving the selectivity of the fishing gear proved to be more beneficial than limiting nominal effort, which was in turn more beneficial than decreasing coastal fleet size.
Modelling occupancy of an imperilled stream fish at multiple scales while accounting for imperfect detection: implications for conservation
Authors: Dextrase Alan J. , Mandrak Nicholas E. , Schaefer James A.
Published: April 2014

Predictive models of species distribution are useful tools to identify habitats of imperilled species for protection, inventory and restoration. Critical aspects of such models include the influence of scale, uncertainties associated with imperfect detection and spatial autocorrelation and transferability of model predictions.

We addressed these issues in developing occupancy models of the imperilled eastern sand darter (Ammocrypta pellucida) based on surveys of the Grand and Thames Rivers, Ontario, Canada.

Eastern sand darter detection probabilities were remarkably different between streams, but factors affecting site occupancy were similar. The proportion of sand and fine gravel was most important, but water clarity and biotic indices also received support in additive models. Accounting for spatial autocorrelation reduced the effect of important covariates.

Occupancy was more closely related to substratum at the site level than factors at broader scales (reach and valley segment), further emphasising the substratum specificity of this species.

Almost all of the top‐ranked site and reach occupancy models had good predictive performance based on assessments of transferability. These models indicate that three formerly occupied Ontario catchments have a high probability of supporting the species and deserve consideration for repatriation.

Our methods demonstrate how a comprehensive approach to occupancy modelling can be used to help guide recovery efforts for imperilled species.
Have we been underestimating the effects of ocean acidification in zooplankton?
Authors: Cripps Gemma , Lindeque Penelope , Flynn Kevin J.
Published: April 2014

Understanding how copepods may respond to ocean acidification (OA) is critical for risk assessments of ocean ecology and biogeochemistry. The perception that copepods are insensitive to OA is largely based on experiments with adult females. Their apparent resilience to increased carbon dioxide (pCO2) concentrations has supported the view that copepods are ‘winners’ under OA. Here, we show that this conclusion is not robust, that sensitivity across different life stages is significantly misrepresented by studies solely using adult females. Stage‐specific responses to pCO2 (385–6000 μatm) were studied across different life stages of a calanoid copepod, monitoring for lethal and sublethal responses. Mortality rates varied significantly across the different life stages, with nauplii showing the highest lethal effects; nauplii mortality rates increased threefold when pCO2 concentrations reached 1000 μatm (year 2100 scenario) with LC50 at 1084 μatm pCO2. In comparison, eggs, early copepodite stages, and adult males and females were not affected lethally until pCO2 concentrations ≥3000 μatm. Adverse effects on reproduction were found, with >35% decline in nauplii recruitment at 1000 μatm pCO2. This suppression of reproductive scope, coupled with the decreased survival of early stage progeny at this pCO2 concentration, has clear potential to damage population growth dynamics in this species. The disparity in responses seen across the different developmental stages emphasizes the need for a holistic life‐cycle approach to make species‐level projections to climate change. Significant misrepresentation and error propagation can develop from studies which attempt to project outcomes to future OA conditions solely based on single life history stage exposures.
Diversity of condensed tannin structures affects rumen in vitro methane production in sainfoin (Onobrychis viciifolia) accessions
Authors: Hatew B. , Hayot Carbonero C. , Stringano E. , Sales L. F. , Smith L. M. J. , Mueller‐Harvey I. , Hendriks W. H. , Pellikaan W. F.
Published: April 2014

Sainfoin is a non‐bloating temperate forage legume with a moderate‐to‐high condensed tannin (CT) content. This study investigated whether the diversity of sainfoin accessions in terms of CT structures and contents could be related to rumen in vitro gas and methane (CH4) production and fermentation characteristics. The aim was to identify promising accessions for future investigations. Accessions differed (P < 0·0001) in terms of total gas and CH4 productions. Fermentation kinetics (i.e. parameters describing the shape of the gas production curve and half‐time gas production) for CH4 production were influenced by accession (P ≤ 0·038), but not by PEG. Accession, PEG and time affected (P < 0·001) CH4 production, but accession and PEG interaction showed only a tendency (P = 0·08). Increase in CH4 due to PEG addition was not related to CT content. Further analysis of the relationships among multiple traits (nutritional composition, CT structure and CH4 production) using principal component analysis (PCA) based on optimally weighted variables revealed differences among accessions. The first two principal component axes, PC1 (57·6%) and PC2 (18·4%), explained 76·0% of the total variation among accessions. Loading of biplots derived from both PCAs made it possible to establish a relationship between the ratio of prodelphinidin:procyanidin (PD:PC) tannins and CH4 production in some accessions. The PD:PC ratio seems to be an important source of variation that is negatively related to CH4 production. These results suggested that sainfoin accessions collected from across the world exhibited substantial variation in terms of their effects on rumen in vitro CH4 production, revealing some promising accessions for future investigations.
An in vitro comparison of irrigation using photon‐initiated photoacoustic streaming, ultrasonic, sonic and needle techniques in removing calcium hydroxide
Authors: Arslan H. , Akcay M. , Capar I. D. , Saygili G. , Gok T. , Ertas H.
Published: May 2014

Aim

To evaluate the effect of various techniques including photon‐initiated photoacoustic streaming (PIPS), ultrasonic, sonic and needle irrigation on the removal of calcium hydroxide [Ca(OH)2] from artificial grooves created in root canals.

Methods

The root canals of 48 extracted single‐rooted teeth with straight canals were prepared using ProTaper rotary instruments up to size 40. After the specimens had been split longitudinally, a standardized groove was prepared in the apical part of one segment that was filled with Ca(OH)2 powder mixed with distilled water. Each tooth was reassembled and the apices closed with wax. The specimens were irrigated for 60 s with one of the following techniques: needle irrigation using 17% EDTA, PIPS with 17% EDTA, ultrasonic irrigation using 17% EDTA and sonic irrigation (EndoActivator) using 17% EDTA. The root segments were then disassembled, and the amount of remaining Ca(OH)2 evaluated under a stereomicroscope at 25× magnification. A pixel count of Ca(OH)2 remaining on the artificially created grooves was recorded as a percentage of the overall groove surface. The data were evaluated statistically using one‐way analysis of variance and the least significant difference post hoc tests at 95% confidence level (P = 0.05).

Results

Photon‐initiated photoacoustic streaming was superior in removing Ca(OH)2 as compared to needle irrigation (P < 0.001), sonic irrigation (P < 0.001) and ultrasonic irrigation (P = 0.046).

Conclusion

Photon‐initiated photoacoustic streaming provided complete removal of Ca(OH)2 from artificial grooves in straight root canals. Ultrasonic irrigation enhanced the Ca(OH)2 removal capacity of irrigating solution but did not provide complete removal from artificial grooves.
Development of a novel modified atmosphere container with a cycle‐time‐controlled perforation for enoki mushroom preservation
Authors: Kwon Min‐Ji , An Duck Soon , Lee Dong Sun
Published: April 2014

A novel container system with a time‐controlled perforation device was designed to create a modified atmosphere (MA) beneficial for preserving 1.5 kg of enoki mushrooms at 10 °C. Periodic cycles of meeting and eclipse of the block‐arc‐shaped perforations on the rotor and the fixed container cover in the device provided the repeated time‐controlled opening/closing of the perforation to control the gas transfer. A mathematical model describing the container atmospheric change was used to determine an optimal design, which is specified with circular opening ratios of 7% for the rotor and 10% for the fixed cover for a 4‐h cycle. The design could create an MA of 1.8% O2 and 19.4% CO2 to preserve the quality in terms of weight loss, mushroom development, colour change, texture and overall appearance. The cycled time control of the perforation was found as an effective means to have MA condition keeping enoki mushrooms fresh.
Romantic Relationships at Work: Why Love Can Hurt
Authors: Wilson Fiona
Published: April 2014

The academic community, practitioner literature and newspapers have all taken an interest in workplace romance. This paper aims to review the literature on workplace romance and to argue that the issue of power is key to understanding the negative consequences for individuals and organizations, linking workplace romance with theories or explanatory models of power. The paper first examines definitions of workplace romance, presents evidence of its prevalence, distinguishes between different types of workplace romance, and then looks at the main issues that managers and organizations face when considering the issue. The approaches taken by research in management, law, psychology and sociology are contrasted. The motivations for romance and the place of culture are described. Secrecy, gender differences and the negative and positive outcomes for men and women are discussed. The link between romance and harassment is explored. The paper looks at what organizations have done to manage romance. The research methods that have been used are reviewed, as are the gaps and weaknesses in order to make recommendations for future research. The review synthesizes accumulated knowledge in both research and practice, ending by identifying recommendations for managers.
Cognitive Performance after Stroke – The Framingham Heart Study
Authors: Weinstein Galit , Preis Sarah R. , Beiser Alexa S. , Au Rhoda , Kelly-Hayes Margaret , Kase Carlos S. , Wolf Philip A. , Seshadri Sudha
Published: April 2014

Background

Individuals with a high risk of stroke are also more prone to cognitive impairment perhaps because of concomitant vascular risk factors. In addition, clinical stroke increases the risk of subsequent dementia. Nevertheless, the relationship between clinical stroke and subsequent cognitive function in initially nondemented individuals remains less clear as most prior studies examined case series without controls.

Aims

To specify among nondemented individuals the cognitive domains affected by clinical stroke, independently of vascular risk factors and prestroke cognition.

Methods

One hundred thirty-two Framingham study participants (mean age = 77 ± 9 years, 54% women) with prospectively validated initial strokes, as well as age- and gender-matched controls, underwent identical cognitive evaluations ∼six-months after the stroke. Linear regression models were used to assess the differences in cognitive scores between stroke cases and controls adjusting for prestroke cognitive function as assessed by Mini-Mental State Examination scores, and with and without adjustment for vascular risk factors.

Results

Adjusting for prestroke cognition and vascular risk factors, persons with stroke had poorer cognitive function in the domains of immediate recall of logical and visual memories (β = −1·27 ± 0·60, P = 0·035; β = −1·03 ± 0·47, P = 0·028, respectively), verbal learning (paired associate test; β = −1·31 ± 0·57, P = 0·023), language (Boston naming test; β = −0·27 ± 0·08, P = 0·002), executive function (digit span backward; β = −0·53 ± 0·21, P = 0·015), and visuospatial and motor skills (block design; β = −3·02 ± 1·06, P = 0·005).

Conclusions

Clinical stroke is associated with subsequent poorer performance in multiple cognitive domains. This association cannot be entirely explained by the individual's cognitive function prior to stroke or by concomitant vascular risk factor levels.