bluuebunny/crossref_metadata_2025 huggingface dataset:
The influence of drought on flow‐ecology relationships in Ozark Highland streams
Authors: Lynch Dustin T. , Leasure Douglas R. , Magoulick Daniel D.
Published: March 2018

Drought and summer drying can have strong effects on abiotic and biotic components of stream ecosystems. Environmental flow‐ecology relationships may be affected by drought and drying, adding further uncertainty to the already complex interaction of flow with other environmental variables, including geomorphology and water quality.

Environment–ecology relationships in stream communities in Ozark Highland streams, USA, were examined over two years with contrasting environmental conditions, a drought year (2012) and a flood year (2013). We analysed fish, crayfish and benthic macroinvertebrate assemblages using two different approaches: (1) a multiple regression analysis incorporating predictor variables related to habitat, water quality, geomorphology and hydrology and (2) a canonical ordination procedure using only hydrologic variables in which forward selection was used to select predictors that were most related to our response variables.

Reach‐scale habitat quality and geomorphology were found to be the most important influences on community structure, but hydrology was also important, particularly during the flood year. We also found substantial between‐year variation in environment–ecology relationships. Some ecological responses differed significantly between drought and flood years, while others remained consistent. We found that magnitude was the most important flow component overall, but that there was a shift in relative importance from low flow metrics during the drought year to average flow metrics during the flood year, and the specific metrics of importance varied markedly between assemblages and years.

Findings suggest that understanding temporal variation in flow‐ecology relationships may be crucial for resource planning. While some relationships show temporal variation, others are consistent between years. Additionally, different kinds of hydrologic variables can differ greatly in terms of which assemblages they affect and how they affect them. Managers can address this complexity by focusing on relationships that are temporally stable and flow metrics that are consistently important across groups, such as flood frequency and flow variability.
Quantifying climate–growth relationships at the stand level in a mature mixed‐species conifer forest
Authors: Teets Aaron , Fraver Shawn , Weiskittel Aaron R. , Hollinger David Y.
Published: March 2018

A range of environmental factors regulate tree growth; however, climate is generally thought to most strongly influence year‐to‐year variability in growth. Numerous dendrochronological (tree‐ring) studies have identified climate factors that influence year‐to‐year variability in growth for given tree species and location. However, traditional dendrochronology methods have limitations that prevent them from adequately assessing stand‐level (as opposed to species‐level) growth. We argue that stand‐level growth analyses provide a more meaningful assessment of forest response to climate fluctuations, as well as the management options that may be employed to sustain forest productivity. Working in a mature, mixed‐species stand at the Howland Research Forest of central Maine, USA, we used two alternatives to traditional dendrochronological analyses by (1) selecting trees for coring using a stratified (by size and species), random sampling method that ensures a representative sample of the stand, and (2) converting ring widths to biomass increments, which once summed, produced a representation of stand‐level growth, while maintaining species identities or canopy position if needed. We then tested the relative influence of seasonal climate variables on year‐to‐year variability in the biomass increment using generalized least squares regression, while accounting for temporal autocorrelation. Our results indicate that stand‐level growth responded most strongly to previous summer and current spring climate variables, resulting from a combination of individualistic climate responses occurring at the species‐ and canopy‐position level. Our climate models were better fit to stand‐level biomass increment than to species‐level or canopy‐position summaries. The relative growth responses (i.e., percent change) predicted from the most influential climate variables indicate stand‐level growth varies less from to year‐to‐year than species‐level or canopy‐position growth responses. By assessing stand‐level growth response to climate, we provide an alternative perspective on climate–growth relationships of forests, improving our understanding of forest growth dynamics under a fluctuating climate.
From tropical shelters to temperate defaunation: The relationship between agricultural transition stage and the distribution of threatened mammals
Authors: Polaina Ester , González‐Suárez Manuela , Kuemmerle Tobias , Kehoe Laura , Revilla Eloy
Published: March 2018

Aim

Agriculture is a key threat to biodiversity; however, its relationship with biodiversity patterns is understudied. Here, we evaluate how the extent, intensity and history of croplands relate to the global distribution of threatened mammals. We propose two hypotheses to explain these relationships: shelter, which predicts that threatened species concentrate in areas with low human land use; and threat, according to which threatened species should concentrate in areas of high human land use.

Location

Global.

Time period

c. 6000 BC – AD 2014.

Major taxa studied

Terrestrial mammals.

Methods

We used boosted regression trees (BRT) that include spatial autocorrelation to investigate the relationship between the proportion of threatened terrestrial mammals [as defined by the International Union for Conservation of Nature (IUCN) Red List] and multiple metrics describing agricultural extent, intensity and history derived from remote sensing data and statistical projections. Data were analysed with a grain size of c. 110 km × 110 km at both global and biogeographical‐realm scales.

Results

Agricultural extent and intensity were the most relevant indicator types, with specific metrics important for each realm. Forest cover (extent) was identified as important in several regions. Tropical regions in early agricultural transition stages (e.g. frontier landscapes) were consistent with the shelter hypothesis, whereas patterns found for regions in later stages (e.g. intensified agricultural landscapes) were mostly found in temperate regions and agreed with the threat hypothesis.

Main conclusions

These results highlight the need to consider multiple land‐use indicators when addressing threats to biodiversity and to separately assess areas with divergent human and ecological histories in global‐scale studies. Different relationships associated with different agricultural transition stages suggest that high concentrations of threatened species may have contrasting meanings in different regions worldwide. We propose a new unifying hypothesis following a cyclic relationship along agricultural transition stages resulting in alternating negative and positive relationships between agriculture and threatened species richness.
Misleading prioritizations from modelling range shifts under climate change
Authors: Sofaer Helen R. , Jarnevich Catherine S. , Flather Curtis H.
Published: March 2018

Aim

Conservation planning requires the prioritization of a subset of taxa and geographical locations to focus monitoring and management efforts. Integration of the threats and opportunities posed by climate change often relies on predictions from species distribution models, particularly for assessments of vulnerability or invasion risk for multiple taxa. We evaluated whether species distribution models could reliably rank changes in species range size under climate and land use change.

Location

Conterminous U.S.A.

Time period

1977–2014.

Major taxa studied

Passerine birds.

Methods

We estimated ensembles of species distribution models based on historical North American Breeding Bird Survey occurrences for 190 songbirds, and generated predictions to recent years given c. 35 years of observed land use and climate change. We evaluated model predictions using standard metrics of discrimination performance and a more detailed assessment of the ability of models to rank species vulnerability to climate change based on predicted range loss, range gain, and overall change in range size.

Results

Species distribution models yielded unreliable and misleading assessments of relative vulnerability to climate and land use change. Models could not accurately predict range expansion or contraction, and therefore failed to anticipate patterns of range change among species. These failures occurred despite excellent overall discrimination ability and transferability to the validation time period, which reflected strong performance at the majority of locations that were either always or never occupied by each species.

Main conclusions

Models failed for the questions and at the locations of greatest interest to conservation and management. This highlights potential pitfalls of multi‐taxa impact assessments under global change; in our case, models provided misleading rankings of the most impacted species, and spatial information about range changes was not credible. As modelling methods and frameworks continue to be refined, performance assessments and validation efforts should focus on the measures of risk and vulnerability useful for decision‐making.
Dullard deficiency causes hemorrhage in the adult ovarian follicles
Authors: Hayata Tadayoshi , Chiga Masahiko , Ezura Yoichi , Asashima Makoto , Katabuchi Hidetaka , Nishinakamura Ryuichi , Noda Masaki
Published: March 2018

In mammals, the ovarian follicles are regulated at least in part by bone morphogenetic protein (BMP) family members. Dullard (also known as Ctdnep1) gene encodes a phosphatase that suppresses BMP signaling by inactivating or degrading BMP receptors. Here we report that the Col1a1‐Cre‐induced Dullard mutant mice displayed hemorrhagic ovarian cysts, with red blood cells accumulated in the follicles, resulting in infertility. Cells expressing Cre driven by Col1a1 2.3‐kb promoter and their descendants were found in granulosa cells in the ovary and in Sertoli cells in the testis. DullardmRNA was localized to granulosa cells in the ovary. Genes involved in steroid hormone genesis including Cyp11a1, Hsd3b1 and Star were reduced, whereas expression of Smad6 and Smad7, BMP‐inducible inhibitory Smads, was up‐regulated in the Dullard mutant ovaries. Tamoxifen‐inducible Dullard deletion in the whole body using Rosa26‐CreER mice also resulted in hemorrhagic ovarian cysts in 2 weeks, which was rescued by administration of LDN‐193189, a chemical inhibitor of BMP receptor kinase, suggesting that the hemorrhage in the Dullard‐deficient ovarian follicles might be caused by increased BMP signaling. Thus, we conclude that Dullard is essential for ovarian homeostasis at least in part via suppression of BMP signaling.
ANTHROPOCENE TIME
Authors: CHAKRABARTY DIPESH
Published: March 2018

Beginning with the question of how a sense of geological time remains strangely withdrawn in contemporary discussions of the Anthropocene in the human sciences and yields place to the more human‐centered time of world history, this article proceeds to discuss the differences between human‐historical time and the time of geology as they relate to the concept of the Anthropocene. The article discusses the difficulty of developing a mode of thinking about the present that would attempt to hold together these two rather different senses of time and ends with a ground‐clearing exercise that might enable the development of such thought.
STORY MAKES HISTORY, THEORY MAKES STORY: DEVELOPING RÜSEN'S HISTORIK IN LOGICAL AND SEMIOTIC DIRECTIONS
Authors: FERNANDEZ JUAN L.
Published: March 2018

This essay will argue that the traditional opposition between narrative and theory in historical sciences is dissolved if we conceive of narratives as theoretical devices for understanding events in time through special concepts that abridge typical sequences of events. I shall stress, in the context of the Historical Knowledge Epistemological Square (HKES) that emerged with the scientization of history, that history is always narrative, story has a theoretical ground of itself, and scientific histories address the need for a conceptual progression in ever‐improved narratives. This will lead to identification of three major theoretical levels in historical stories: naming, plotting (or emplotment), and formalizing. We revisit Jörn Rüsen's theory of history as the best starting point, and explore to what extent it could be developed by (i) taking a deeper look into narratological knowledge, and (ii) reanalyzing logically the conceptual strata in order to bridge the overrated Forschung/Darstellung (research/exposition) divide. The corollary: we should consider (scientific) historical writing as the last step of historical research, not as the next step after research is over. This thesis will drive us to a reconsideration of the German Historik regarding the problem of interpretation and exposition. Far from alienating history from science, narrative links history positively to anthropology and biology. The crossing of our triad name‐plot‐model with Rüsen's four theoretical levels (categories‐types‐concepts‐names) points to the feasibility of expanding Rüsen's Historik in logical and semiotic directions. Story makes history, theory makes story, and historical reason may proceed.
ROMAN HISTORY, THEN AND NOW
Authors: Jordan David P.
Published: March 2018

The argument here is that despite the many similarities of writing the history of ancient Rome, whether the Republic or the Empire, there are stark and significant differences between Edward Gibbon and Mary Beard. In part this is a matter of style and literary genius. It is also evidence of a vast cultural difference, reflected in changing attitudes about writing history and its importance. Beard is impatient with Gibbon's oratorical formality and conceits. Her own writing is easy and unmannered. These literary habits are determined by audience as well as personality. Gibbon addresses the English ruling class and enlightened opinion. His concerns are politics, religion, and law—the interests of his readers who governed and shaped opinion. Beard is more interested in the private and personal, subjects that until recently had only a marginal place in historical writing. She relies heavily on sources that were unknown to Gibbon, and might not have interested him anyhow. Her style mirrors these concerns. She does not assume her readers have had a Classical education nor that they know the general outlines of Roman history. She has little or no tolerance for Gibbon's obsession with religion, and, at least in SPQR, slight interest in either paganism or the rise of Christianity. Her thousand‐year slice of history—Gibbon also tackled a millennium—stops well short of Gibbon's broad philosophical vision of Rome as the cradle of Europe. These contrasts in style, taste, sources, and personality are not offered in judgment, but as commentary on the continuing vitality of Roman history.
SMOKING AND MORTALITY: NEW EVIDENCE FROM A LONG PANEL
Authors: Darden Michael , Gilleskie Donna B. , Strumpf Koleman
Published: March 2018

Many public health policies are rooted in findings from medical and epidemiological studies that fail to consider behavioral influences. Using nearly 50 years of data from the Framingham Heart Study's male participants, we evaluate the longevity consequences of different lifetime smoking patterns by jointly estimating smoking behavior and health outcomes over the life cycle, by richly including smoking and health histories, and by flexibly incorporating correlated unobserved heterogeneity. Unconditional difference‐in‐mean calculations that treat smoking behaviors as random indicate a 9.3‐year difference in age of death between lifelong smokers and nonsmokers; our findings suggest the bias‐corrected difference is 4.3 years.
The Relevance of Modernity to Contemporary East Asia: An Outline
Authors: Wang Horng‐luen
Published: March 2018

This article offers a framework for exploring the relevance of modernity to contemporary East Asia. I first examine different conceptualizations of modernity, paying special attention to Eisenstadt's influential concept of multiple modernities. Second, I point out the limitations and flaws of Eisenstadt's theory by drawing on nationalist politics in East Asia as an illustrative case. In particular, I examine the so‐called “history perception problem,” which has been created by war and shaped by the legacies of war, to demonstrate the peculiar features of modernity in East Asia. Third, I use the works by three scholars as examples to show how intellectuals in China, South Korea, and Taiwan respond to the tensions between universalism and particularism, which, as a whole, reflect what can be called “East Asian modernity.” And finally, I try to respond to the controversial but fashionable question that is peculiar to East Asia: can modernity be overcome? It is argued that East Asia can be understood through the lens of modernity, and vice versa. Nowadays, modernity has become a global condition in both geographical and topological senses. It is not something to be overcome, but a condition that we all live in and should learn to live with, here and now.
A proposed clinical research support career pathway for noninvestigators
Authors: Smith Sheree , Gullick Janice , Ballard Jacqueline , Perry Lin
Published: March 2018

Aim

To discuss the international experience of clinical research support for noninvestigator roles and to propose a new pathway for Australia, to promote a sustainable research support workforce capable of delivering high‐quality clinical research.

Background

Noninvestigator research support roles are currently characterized by an ad hoc approach to training, with limited role delineation and perceived professional isolation with implications for study completion rates and participant safety. A focused approach to developing and implementing research support pathways has improved patient recruitment, study completion, job satisfaction, and research governance.

Data Sources

The Queensland and New South Wales state‐based Nurses' Awards, the Australian Qualifications Framework, and a University Professional (Research) Staff Award. Research nurses in the clinical environment improve study coordination, adherence to study protocol, patient safety, and clinical care.

Conclusion

A career pathway that guides education and outlines position descriptions and skill sets would enhance development of the research support workforce. This pathway could contribute to changing the patient outcomes through coordination and study completion of high‐quality research. A wide consultative approach is required to determine a cost‐effective and feasible approach to implementation and evaluation of the proposed pathway.
Relación entre el empleo juvenil y el de los trabajadores de edad en 20 países de la OCDE
Authors: JI Eun Jeong
Published: March 2018

Numerosos países de la OCDE, inspirados por la teoría de la «cantidad fija de trabajo», han promovido políticas de jubilación anticipada en respuesta al aumento del desempleo desde los años setenta. En realidad, se ha observado una correlación positiva entre empleo juvenil y empleo de personas de edad en el conjunto de la OCDE sobre la base de estimaciones promedio. Dada la falta de estudios que exploren la heterogeneidad que dichos promedios podrían esconder, el autor investiga las diferencias en cuanto a dicha relación entre 20 países de la OCDE mediante análisis de conglomerados y escalamiento multidimensional.
Sleep on the ward in intensive care unit survivors: a case series of polysomnography
Authors: Wilcox Mary Elizabeth , Lim Andrew S. , Pinto Ruxandra , Black Sandra E. , McAndrews Mary Pat , Rubenfeld Gordon D.
Published: March 2018

Background

Few studies have investigated sleep in patients after intensive care despite the possibility that inadequate sleep might further complicate an acute illness impeding recovery.

Aims

To assess the quality and quantity of a patient's sleep on the ward by polysomnography (PSG) within a week of intensive care unit (ICU) discharge and to explore the prevalence of key in‐ICU risk factors for persistent sleep fragmentation.

Methods

We enrolled 20 patients after they have been mechanically ventilated for at least 3 days and survived to ICU discharge. We included all patients over the age of 16 years and excluded patients with advanced cognitive impairment or who were unable to follow simple commands before their acute illness, primary admission diagnosis of neurological injury, uncontrolled psychiatric illness or not fluent in English.

Results

Twenty patients underwent an overnight PSG recording on day 7 after ICU discharge (SD, 1 day). ICU survivors provided 292.8 h of PSG recording time with median recording times of 16.8 h (Interquartile range (IQR), 15.0–17.2 h). The median total sleep time per patient was 5.3 h (IQR, 2.6–6.3 h). In a multivariable regression model, postoperative admission diagnosis (P = 0.04) and patient report of poor ICU sleep (P = 0.001) were associated with less slow‐wave (restorative) sleep on the wards after ICU discharge.

Conclusions

Patients reported poor sleep while in the ICU, and a postoperative admission diagnosis may identify a high‐risk subgroup of patients who may derive greater benefit from interventions to improve sleep hygiene.
The making of the German minimum wage: a case study of institutional change
Authors: Bosch Gerhard
Published: March 2018

In the more recent dualistic theories, Germany is cited as an example of a less solidaristic equilibrium, in which ‘producer coalitions’ between core workforces supposedly unaffected by deregulation and their employers prevented the introduction of a minimum wage. The present article shows that such an equilibrium never existed. Core workforces are being threatened by the outsourcing of jobs to the low‐wage sector. This threat created the breeding ground for a joint campaign by manufacturing and service unions for a minimum wage, which made it possible to amalgamate the unions' considerable resources at company level, their strength being derived from the German system of codetermination. Under pressure from the manufacturing unions in particular, the arrangements for the minimum wage follow, as far as possible, the traditions of free collective bargaining. As a result, the social partners in Germany have a considerably stronger influence on the minimum wage than those in the UK.
Complex cognitive skill retention: The roles of general mental ability and refresher interventions in a simulated vocational setting
Authors: Frank Barbara , Kluge Annette
Published: March 2018

In organizations, the assessment of mental abilities is a common way to predict learning success. This paper analyses the effect of general mental ability on skill retention and examines the relationship between refresher interventions and general mental ability in terms of skill retention. Two hundred sixty‐six adult participants were trained to perform a complex cognitive skill in a simulated chemical processing plant (Week 1). After 1 week, 158 participants received intermediate computer‐assisted refresher intervention training in which the skill was applied (Week 2; 108 received no intervention). Finally, participants had to recall (perform) the learned skill after 2 weeks (Week 3). Results show that general mental ability alone affects skill retention with small effect sizes and that refresher interventions affect skill retention positively for low and high general mental ability levels. The findings suggest that persons with low and high general mental abilities benefit equally from refresher interventions in order to maintain complex cognitive skills.
The impact of treatment delivery format on response to cognitive behaviour therapy for preadolescent children with anxiety disorders
Authors: McKinnon Anna , Keers Robert , Coleman Jonathan R.I. , Lester Kathryn J. , Roberts Susanna , Arendt Kristian , Bögels Susan M. , Cooper Peter , Creswell Cathy , Hartman Catharina A. , Fjermestad Krister W. , In‐Albon Tina , Lavallee Kristen , Lyneham Heidi J. , Smith Patrick , Meiser‐Stedman Richard , Nauta Maaike H. , Rapee Ronald M. , Rey Yasmin , Schneider Silvia , Silverman Wendy K. , Thastum Mikael , Thirlwall Kerstin , Wergeland Gro Janne , Eley Thalia C. , Hudson Jennifer L.
Published: March 2018

Background

Several delivery formats of cognitive behaviour therapy (CBT) for child anxiety have been proposed, however, there is little consensus on the optimal delivery format. The primary goal of this study was to investigate the impact of the child's primary anxiety diagnosis on changes in clinical severity (of the primary problem) during individual CBT, group CBT and guided parent‐led CBT. The secondary goal was to investigate the impact of the child's primary anxiety diagnosis on rates of remission for the three treatment formats.

Methods

A sample of 1,253 children (5–12 years; Mage = 9.3, SD = 1.7) was pooled from CBT trials carried out at 10 sites. Children had a primary diagnosis of generalised anxiety disorder (GAD), social anxiety disorder (SoAD), specific phobia (SP) or separation anxiety disorder (SAD). Children and parents completed a semistructured clinical interview to assess the presence and severity of DSM‐IV psychiatric disorders at preintervention, postintervention and follow‐up. Linear mixture modelling was used to evaluate the primary research question and logistic modelling was used to investigate the secondary research question.

Results

In children with primary GAD, SAD or SoAD, there were no significant differences between delivery formats. However, children with primary SP showed significantly larger reductions in clinical severity following individual CBT compared to group CBT and guided parent‐led CBT. The results were mirrored in the analysis of remission responses with the exception that individual CBT was no longer superior to group CBT for children with a primary SP. The difference between individual and group was not significant when follow‐up data were examined separately.

Conclusions

Data show there may be greater clinical benefit by allocating children with a primary SP to individual CBT, although future research on cost‐effectiveness is needed to determine whether the additional clinical benefits justify the additional resources required.
Response of Cry3Bb1‐resistant western corn rootworm (Coleoptera: Chrysomelidae) to Bt maize and soil insecticide
Authors: Shrestha R. B. , Jakka S. R. K. , Gassmann A. J.
Published: March 2018

Cry3Bb1‐resistant western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), is abundant and widely distributed in Iowa. Possible options for management of Cry3Bb1‐resistant populations may include planting of Cry34/35Ab1 maize, maize pyramided with Cry3Bb1 and Cry34/35Ab1 and application of soil‐applied insecticide to either Bt maize or maize that lacks a Bt trait targeting corn rootworm. However, empirical evidence is lacking about how these tactics will affect root injury to maize and survival of this pest to adulthood. We conducted a 2‐year field experiment, in fields known to harbour Cry3Bb1‐resistant western corn rootworm, and quantified the effects of five maize hybrids with and without soil‐applied insecticide, measuring emergence of adults and root injury. Maize with Cry34/35Ab1, both alone or pyramid with Cry3Bb1, significantly reduced the number of adults and the level of root injury, indicating that it was a useful tool for the mitigation of Cry3Bb1‐resistant rootworm. An application of soil insecticide reduced the level of adult emergence and root injury in non‐Bt maize and Cry3Bb1 maize. However, it did not provide any additional reduction in adult emergence or root injury when applied to Cry34/35Ab1 maize or pyramid maize. Both adult emergence and root injury were similar between soil insecticide applied to non‐Bt maize and Cry3Bb1 maize. Our results indicate that useful strategies to manage Cry3Bb1‐resistant rootworm include Cry34/35Ab1 maize, either alone or in a pyramid, and soil insecticide applied to maize lacking a rootworm active Bt toxin, in addition to other IPM practices such as crop rotation.
Novel treatment of in‐office tooth bleaching sensitivity: A randomized, placebo‐controlled clinical study
Authors: Mehta Deepak , Jyothi S. , Moogi Prashant , Finger Werner J. , Sasaki Keiichi
Published: March 2018

Objectives

Aim of this clinical trial was to investigate the effect of a calcium phosphate based desensitizer paste applied prior to in‐office tooth whitening on bleaching sensitivity (BS).

Methods

This crossover study was designed as randomized double‐blinded, placebo‐controlled trial. The desensitizer paste Teethmate AP (TAP) contains tetracalcium phosphate and dicalcium phosphate anhydrous in glycerol and polyethylene glycol, whereas placebo (PLA) is a calcium phosphate free analog. Fifty patients with sound maxillary incisors and canines were enrolled. Tooth shades were determined with a Vitapan Classic Shade guide. Randomly, TAP and PLA were applied to the left or to the right anterior teeth. After rinsing and air‐drying the bleaching gel (Opalescence Boost PF 40%) was applied and left on the labial surfaces for 15 minutes. Sensitivity was recorded using a 10 cm visual analog scale (VAS) before, at 5, 10, and 15 minutes during, and at 1 hour, 1, 2, and 7 days after bleaching. Tooth whitening was determined with the shade guide after 1 day and 1 week.

Results

Prebleaching desensitization with TAP reduced BS significantly when compared with PLA. Between 1 and 7 days the average sensitivity scores were close to zero, whereas the average scores for PLA were significantly higher during this time interval. Independent from the desensitizing treatment after 1 and 7 days the medians of the shades were between 5 and 3.5 units brighter.

Conclusions

Prebleaching desensitization with TAP was effective in reducing BS during and after tooth whitening treatment and had no adverse effect on the bleaching result.

Clinical significance

Prebleaching topical application of a calcium phosphate containing compound reduced significantly bleaching sensitivity during a single 15 minutes treatment and up to one week with a 40% hydrogen peroxide containing gel without compromising tooth whitening.
Diabetes, Heart Disease, and Dementia: National Estimates of Functional Disability Trajectories
Authors: MacNeil Vroomen Janet L. , Han Ling , Monin Joan K. , Lipska Kasia J. , Allore Heather G.
Published: March 2018

Objectives

To estimate the associations between diabetes, heart disease, and dementia, which may increase the difficulty of self‐care; model functional disability trajectories jointly with attrition (death or dropout) over 5 years.

Design

Population‐based complex survey design.

Setting

National Health and Aging Trends Study.

Participants

Community‐dwelling Medicare beneficiaries aged 65 and older (N=7,609).

Measurements

National estimates were generated using sampling weights. Sociodemographic characteristics, self‐reported physician‐diagnosed chronic conditions, six activities of daily living (ADL), and cognitive status were ascertained in annual in‐person interviews. A joint model using group‐based trajectory modeling was used to estimate the number of ADL disabilities and attrition probability. Multinomial logistic regression with survey weights was used to estimate the association between diabetes, heart disease, and dementia and resultant trajectories of disability, with the least disabled trajectory used as a reference.

Results

Three functional disability trajectories were identified: 26.9 million (76.3%) individuals with no disability and a constant study attrition of 14.3%, 4.9 million (13.9%) with mild and increasing disability and 12% attrition in 2012 and 27.2% in 2015, and 3.4 million (9.7%) with severe and increasing disability and 25.4% attrition in 2012 and 35% in 2015. Persons with possible dementia, possible dementia and diabetes, or possible dementia with diabetes and heart disease had significantly greater odds of being on the mild disability trajectory than those with no disability. Persons with probable dementia, representing more than 1.5 million persons, regardless of concurrent conditions, had significantly greater odds of being on the severe disability trajectory than on the no disability trajectory.

Conclusions

Methods that generate national estimates and account for attrition and for multiple chronic conditions and cognitive status may be useful for health policy‐makers to make decisions on care provisions and services.
Hypothalamic epigenetics driving female puberty
Authors: Toro C. A. , Aylwin C. F. , Lomniczi A.
Published: March 2018

Puberty involves a series of morphological, physiological and behavioural changes during the last part of the juvenile period that culminates in the attainment of fertility. The activation of the pituitary‐gonadal axis by increased hypothalamic secretion of gonadotrophin‐releasing hormone (GnRH) is an essential step in the process. The current hypothesis postulates that a loss of transsynaptic inhibition and a rise in excitatory inputs are responsible for the activation of GnRH release. Similarly, a shift in the balance in the expression of puberty activating and puberty inhibitory genes exists during the pubertal transition. In addition, recent evidence suggests that the epigenetic machinery controls this genetic balance, giving rise to the tantalising possibility that epigenetics serves as a relay of environmental signals known for many years to modulate pubertal development. Here, we review the contribution of epigenetics as a regulatory mechanism in the hypothalamic control of female puberty.
Phylogenetic patterns and correlation of key structures for jumping: bone crests and cross‐sectional areas of muscles inLeptodactylus(Anura, Leptodactylidae)
Authors: Ponssa María Laura , Fratani Jéssica , Abdala Virginia
Published: March 2018

Anurans are characterized by their saltatory mode of locomotion, which is associated with a specific morphology. The coordinated action of the muscles and bones of the pelvic girdle is key to the transmission of the force of the hindlimbs to the axial skeleton during jumping. Two features are critical for optimal locomotory performance: the cross‐sectional area of muscle and the bone crest attachment sites. The first character is a proxy of the force exerted by the muscle, whereas the crests are muscle attachments sites related to muscle force. The provisory relationship between these features has previously been identified and bone crest size can be used to infer the magnitude and, therefore, muscle force in fossils records. In this work, we explore the correlation between the cross‐sectional area of essential muscles to the jumping mechanism (longissimus dorsi, extensor iliotibialis B, tenuissimus, puboischiofemoralis internus B, coccygeo‐sacralis and coccygeo‐iliacus) and the bone crests where these muscles are inserted (dorsal tubercle, dorsal crest and urostylar crest) in species of the genusLeptodactylus. This genus, along with other leptodactylids, exhibits a diversity of locomotor modes, including jumping, hopping, swimming and burrowing. We therefore analyzed the morphometric variation in the two features, cross‐sectional area and bone crest area, expecting a correlation with different locomotor types. Our results showed: (i) a correlation between the urostylar crest and the cross‐sectional area of the related muscles; (ii) that the bone crest surface area of urostyle and ilium and the cross‐sectional area of the corresponding muscles can be utilized to infer locomotor faculties in leptodactylid frogs; and (iii) that the evolution of both characters demonstrates a general tendency from lower values in leptodactylid ancestors to higher values in theLeptodactylusgenus. The results attest to the importance of the comparison of current ecological and phylogenetic analogues as they allow us to infer functionality and behavior in fossil and extant groups based on skeletal evidence. Phylogenetic patterns in character evolution and their correlation with locomotory types could imply that functional restrictions are also inherited in leptodactylid.
A novel method to visualise the three‐dimensional organisation of the human cerebral cortical vasculature
Authors: Harrison C. H. , Buckland G. R. , Brooks S. E. , Johnston D. A. , Chatelet D. S. , Liu A. K. L. , Gentleman S. M. , Boche D. , Nicoll J. A. R.
Published: March 2018

Current tissue‐clearing protocols for imaging in three dimensions (3D) are typically applied to optimally fixed, small‐volume rodent brain tissue – which is not representative of the tissue found in diagnostic neuropathology laboratories. We present a method to visualise the cerebral cortical vasculature in 3D in human post‐mortem brain tissue which had been preserved in formalin for many years. Tissue blocks of cerebral cortex from two control cases, two Alzheimer's brains and two cases from Alzheimer's patients immunised against Aβ42 were stained with fluorescent Lycopersicon esculentum agglutinin (Tomato lectin), dehydrated and cleared using an adapted three‐dimensional imaging of solvent cleared organs (3DISCO) protocol to visualise the vascular endothelium. Tissue was imaged using light sheet and confocal microscopy and reconstructed in 3D using amira software. The method permits visualisation of the arrangement of the parallel penetrating cortical vasculature in the human brain. The presence of four vascular features including anastomosis, U‐shaped vessels, spiralling and loops were revealed. In summary, we present a low cost and simple method to visualise the human cerebral vasculature in 3D compatible with prolonged fixation times (years), allowing study of vascular involvement in a range of normative and pathological states.
Conversations between Interiors
Authors: Roes Remco , Snowdon Peter
Published: March 2018

The point of departure of this article is a collaborative installation work in whose creation one of the authors (Remco Roes) participated. The article combines a visual essay, composed from images documenting both the final exhibition and the process leading up to it, and a written commentary that attempts to point at—or point out—how knowledge or thinking may occur within or through a sequence of images such as this. These two essays, and the oblique relationship between them, are designed to shed light not only on one specific work of art but, more generally, on how we may inhabit different kinds of interiors, whether or not they are purely “physical.” It also reflects on the visual essay genre as itself a way of thinking through artistic, design and philosophical problems.
Writing Rooms: Reconsidering the Notion of a Room of One's Own
Authors: Close Susan
Published: March 2018

Writing rooms, whether permanently situated or temporarily constructed in transit, have a long history of allowing writers an escape from daily obligations and distractions in order to focus on the task at hand. This essay considers these interiors from a feminist perspective informed by the process of cultural analysis. Here, I argue that, particularly for women, the writing room is a retreat that allows for the solitary reflection necessary for the writing process. Often, what we write is influenced by where we write. Evidence for this is found in close readings informed by the concepts of mise–en–scene and place making of a representative selection of six photographs of writing rooms where I have worked. The following theorists and writers inform my analysis: Mieke Bal, Tim Cresswell, Rebecca Solnit, Yi–Fu Tuan, and Virginia Woolf. For all their obvious differences, what makes these writing rooms productive is that, in their own way, all have been environments free from distraction that have been able to provide the calm and quiet that has allowed writing to flourish.
Wear and Corrosion Interactions at the Titanium/Zirconia Interface: Dental Implant Application
Authors: Sikora Craig L. , Alfaro Maria F. , Yuan Judy Chia‐Chun , Barao Valentim A. , Sukotjo Cortino , Mathew Mathew T.
Published: March 2018

Purpose

Dental implants have been shown to have predictable success, but esthetic complications often arise. To reduce tissue shadowing from titanium, zirconia abutments may be used; however, the literature suggests that the use of zirconia leads to greater destruction of the implant interface that may result in biological complications such as titanium tattoos and heavy metal toxicity. Previous studies have examined the mechanical aspects of this implant/abutment relationship, but they have not accounted for the corrosive degradation that also takes place in the dynamic environment of the oral cavity. This study investigated the combined effect of both wear and corrosion on the materials at the implant and abutment interface.

Materials and Methods

Using a simulated oral tribocorrosive environment, titanium (Ti) and zirconia (Zr) abutment materials were slid against titanium and Roxolid implant alloys. The four couplings (Ti/Ti, Ti/Rox, Zr/Ti, Zr/Rox) were selected for the tribocorrosion tests (N = 3). The testing was conducted for 25K cycles, and the coefficient of friction (CoF) and voltage evolution were recorded simultaneously. Following the tribocorrosion assays, the wear volume loss was calculated, and surface characterization was performed. Statistical analysis was completed using a one‐way ANOVA followed by post‐hoc Bonferroni comparisons.

Results

Zr/Ti groups had the highest CoF (1.1647), and Ti/Ti had the lowest (0.5033). The Zr/Ti coupling generated significantly more mechanical damage than the Ti/Ti group (p = 0.021). From the corrosion aspect, the Ti/Ti groups had the highest voltage drop (0.802 V), indicating greater corrosion susceptibility. In comparison, the Zr/Roxolid group had the lowest voltage drop (0.628 V) and significantly less electrochemical degradation (p = 0.019). Overall, the Ti/Ti group had the largest wear volume loss (15.1 × 107 μm3), while the Zr/Ti group had the least volume loss (2.26 × 107 μm3). Both zirconia couplings had significantly less wear volume than the titanium couplings (p < 0.001).

Conclusions

This study highlights the synergistic interaction between wear and corrosion, which occurs when masticatory forces combine with the salivary environment of the oral cavity. Overall, the zirconia groups outperformed the titanium groups. In fact, the titanium groups generated 5 to 6 times more wear to the implant alloys as compared with the zirconia counterparts. The best performing group was Zr/Ti, and the worst performing group was Ti/Ti.
In Vitro Evaluation of Cell Compatibility of Dental Cements Used with Titanium Implant Components
Authors: Marvin Jason C. , Gallegos Silvia I. , Parsaei Shaida , Rodrigues Danieli C.
Published: March 2018

Purpose

To evaluate the biocompatibility of five dental cement compositions after directly exposing human gingival fibroblast (HGF) and MC3T3‐E1 preosteoblast cells to cement alone and cement applied on commercially pure titanium (cpTi) specimens.

Materials and Methods

Nanostructurally integrated bioceramic (NIB), resin (R), resin‐modified glass ionomer (RMGIC), zinc oxide eugenol (ZOE), and zinc phosphate (ZP) compositions were prepared according to the respective manufacturer's instructions. Samples were prepared in cylindrical Teflon molds or applied over the entire surface of polished cpTi discs. All samples were cured for 0.5, 1, 12, or 24 hours post‐mixing. Direct contact testing was conducted according to ISO 10993 by seeding 6‐well plates at 350,000 cells/well. Plates were incubated at 37°C in a humidified atmosphere with 5% CO2 for 24 hours before individually plating samples and cpTi control discs. Plates were then incubated for an additional 24 hours. Microtetrazolium (MTT) cell viability assays were used to measure sample cytotoxicity.

Results

For samples that cured for 24 hours prior to direct contact exposure, only NIB and ZP cements when cemented on cpTi demonstrated cell viability percentages above the minimum biocompatibility requirement (≥70%) for both the investigative cell lines. R, RMGIC, and ZOE cements exhibited moderate to severe cytotoxic effects on both cell lines in direct contact and when cemented on cpTi specimens. For HGF cells, ZOE cemented‐cpTi specimens exhibited significantly decreased cytotoxicity, whereas RMGIC cemented‐cpTi specimens exhibited significantly increased cytotoxicity.

Conclusions

Despite previous studies that showed enhanced cpTi corrosion activity for fluoride‐containing compositions (NIB and ZP), there was no significant difference in cytotoxicity between cement alone and cemented‐cpTi. In general, the MC3T3‐E1 preosteoblast cells were more sensitive than HGF cells to cement composition. Ultimately, cement composition played a significant role in maintaining host cell compatibility. Results of this work help illustrate the impact of different cement formulations on host cell health and emphasize the need for understanding material properties when selecting certain formulations of dental cements, which can ultimately influence the survival of dental implant systems.
Spatial and social mobility
Authors: Borck Rainald , Wrede Matthias
Published: March 2018

This paper analyzes the relationship between spatial mobility and social mobility. It develops a two‐skill‐type spatial equilibrium model of two regions with location preferences where each region consists of an urban area that is home to workplaces and residences and an exclusively residential suburban area. The paper demonstrates that relative regional social mobility is negatively correlated with segregation and inequality. In the model, segregation, income inequality, and social mobility are driven by differences between urban and residential areas in commuting cost differences between high‐skilled and low‐skilled workers, and also by the magnitude of taste heterogeneity.
Enteric motor dysfunctions in experimental chronic pancreatitis: Alterations of myenteric neurons regulating colonic motility in rats
Authors: Chen L. , Yu B. , Luo D. , Lin M.
Published: March 2018

Background

The mechanism underlying gastrointestinal (GI) dysmotility associated with chronic pancreatitis (CP) has not been fully elucidated, and enteric nervous system (ENS) has an important regulatory role in gastrointestinal motor function. The aim of this study is to investigate the effect of ENS in the colonic hypomotility induced by trinitrobenzene sulfonic acid (TNBS) infusion which mimics CP.

Methods

Male Sprague‐Dawley rats were submitted to CP which was induced by pancreatic infusion of 2% TNBS, or sham group with treatment of equal saline. Three weeks after induction of CP, we pathologically examined the inflammation of pancreas and counted the number of withdrawal events stimulated by Von Frey filaments to evaluate hyperalgesia. The gastrointestinal transit rate was measured using Carbon inkl driving test, and the contraction activities of colonic muscle strip were studied in an organ bath system. The expression of choline acetyltransferase (ChAT) and nitric oxide synthase (NOS) in colonic myenteric plexus (MP) of ENS were investigated by Western blotting and double immunofluorescence staining.

Key Results

In TNBS‐treated group, rats had the signs of chronic pancreatitis 3 weeks after intraductal infusion and had increased sensitivity to mechanical stimulation of the abdomen. For rats with CP, the gastrointestinal transit rate was reduced; in addition, the contractile activities of longitudinal muscle (LM) and circular muscle (CM) strips of distal colon in TNBS group were lower than those in sham group. Immunofluorescence demonstrated that the percentage of ChAT‐immunoreactive (IR) neurons in the MP was decreased, but the proportion of NOS‐IR neurons in the MP was increased when compared with sham‐operated group. Western blotting proved that TNBS infusion down‐regulated ChAT but up‐regulated NOS expression in the colon MP.

Conclusions & Inferences

Decreased ChAT‐IR neurons and increased NOS‐IR in the MP of colon ENS may contribute to the pathogenesis of colonic dysmotility in CP.