bluuebunny/crossref_metadata_2025 huggingface dataset:
Expression of G1/S‐cyclins and cyclin‐dependent kinase inhibitors in actinic keratosis and squamous cell carcinoma
Authors: Brasanac Dimitrije , Stojkovic‐Filipovic Jelena , Bosic Martina , Tomanovic Nada , Manojlovic‐Gacic Emilija
Published: September 2015

Background

Actinic keratosis (AK) and Bowen's disease (squamous cell carcinoma in situ, SCCIS) are pre‐invasive stages in the development of squamous cell carcinoma (SCC).

Methods

Immunohistochemical study of cyclin D1, cyclin E, p16INK4a and p21Cip1/Waf1 in AK (53 cases), SCCIS (16 cases) and SCC (40 cases), in relation to the type of the lesion and SCC prognostic parameters (grade, diameter and thickness).

Results

Diffuse cyclin D1 distribution was more frequent in SCCIS and SCC than in AK (p = 0.03) and similar pattern was observed for p16INK4a. For cyclin E, central distribution dominated in SCC compared with the AK (p = 0.001) and SCCIS (p = 0.03). p21Cip1/Waf1 displayed suprabasal distribution more frequently in AK than in SCCIS (p = 0.001) and SCC (p = 0.0004). Semiquantitative assessment showed more positive cells in AK (p = 0.04) and SCCIS (p = 0.04) than in SCC for cyclin E. SCC with diameter over 20 mm and those thicker than 6 mm revealed higher labeling index with p16INK4a and p21Cip1/Waf1, respectively.

Conclusions

Our results suggest different alterations for p16INK4a and p21Cip1/Waf1 in AK, SCCIS and SCC. Immunostaining distribution showed closer correlation with the type of the lesion, whereas percentage of positive cells displayed better association with the SCC prognostic parameters.
First‐time House Buying and Catch‐up: A Cohort Study
Authors: Bottazzi Renata , Crossley Thomas F. , Wakefield Matthew
Published: September 2015

We investigate whether different ages of first‐time house buying lead to persistent differences in homeownership between cohorts. Our data span nearly 40 years and multiple cycles of England's volatile house prices. Ownership rates at thirty have differed substantially, with a significant negative association with prices. The persistence of differences is assessed using synthetic cohort techniques. Two methods of dealing with measurement error problems both indicate that cohorts with low ownership rates at thirty catch up almost all of the ownership gap by forty. Earlier access to homeownership may result in the ownership of slightly larger homes at around forty.
Managing Haemophilia for Life: 5th Haemophilia Global Summit
Authors: Hermans Cedric , Dolan Gerry , Jennings Ian , Windyga Jerzy , Lobet Sébastien , Rodríguez‐Merchán E. Carlos , Di Minno Matteo Nicola Dario , Jiménez‐Yuste Víctor , O'Mahony Brian
Published: September 2015

The 5th Haemophilia Global Summit was held in Barcelona, Spain, in September 2014. The programme was designed by an independent Scientific Steering Committee of haemophilia experts and explored issues relevant to the practical management of haemophilia, as well as key opportunities and challenges for care in the future. The topics outlined in this supplement were selected by the Scientific Steering Committee for their relevance to improving haemophilia care globally. In this supplement from the meeting, Gerry Dolan explores pharmacokinetics and dynamics in haemophilia, and Gerry Dolan and Ian Jennings jointly address the role of the laboratory in haemophilia care. The potential benefits of low‐dose prophylaxis regimens for people with haemophilia in the developing world are reviewed by Jerzy Windyga, and the question of whether ‘Future haemophilia research should be undertaken in the developing world’ is debated by Jerzy Windyga and Cedric Hermans. Management strategies for ankle arthropathy are discussed by Sébastien Lobet and E. Carlos Rodríguez‐Merchán, and the use of ultrasound for the early detection of haemophilic arthropathy is addressed by Matteo Nicola Dario Di Minno and Víctor Jiménez‐Yuste. Finally, the role of patients in the future of haemophilia care is reviewed by Brian O'Mahony.
Extreme events in running waters
Authors: Ledger Mark E. , Milner Alexander M.
Published: September 2015

Extreme climatic events are a natural feature of climate variability and a major organising force in running waters. Climate change is shifting the occurrence of extremes, and understanding the far‐reaching consequences for river and stream ecosystems is a research priority.

The aim of this special issue is to unite research on the wide array of contrasting extreme events affecting river and stream ecosystems globally, including heat waves and hot days, fires, droughts, heavy rainfall and floods, tropical cyclones, storm surges and coastal flooding.

This issue contains reviews as well as observational and experimental case studies that assess the ecological impacts of extreme events at multiple levels of biological organisation, from individuals to ecosystems and food webs, in river and stream ecosystems from the poles to the tropics. Together, these papers synthesise knowledge of extreme events and their effects, identify research gaps and propose new hypotheses and approaches to guide future research.

The contributions reveal that impacts of single events such as catastrophic floods, droughts and heat waves are highly context dependent, ranging from deleterious to beneficial, and are contingent upon event magnitude, extent and timing relative to life cycles of constituent species. Not all extreme events generate extreme ecological impacts, but combinations of events that are cumulative, compound or cross key biological or physical thresholds may have the most adverse ecological consequences.

Long‐term monitoring programmes and sensor networks are essential in describing rare and usual events. Other approaches, including experiments, will be needed to gain a stronger mechanistic understanding of extreme events, and to predict and manage future events that may be more frequent and intense.
Nicotinic acetylcholine receptors: upregulation, age‐related effects and associations with drug use
Authors: Melroy‐Greif W. E. , Stitzel J. A. , Ehringer M. A.
Published: September 2015

Nicotinic acetylcholine receptors are ligand‐gated ion channels that exogenously bind nicotine. Nicotine produces rewarding effects by interacting with these receptors in the brain's reward system. Unlike other receptors, chronic stimulation by an agonist induces an upregulation of receptor number that is not due to increased gene expression in adults; while upregulation also occurs during development and adolescence there have been some opposing findings regarding a change in corresponding gene expression. These receptors have also been well studied with regard to human genetic associations and, based on evidence suggesting shared genetic liabilities between substance use disorders, numerous studies have pointed to a role for this system in comorbid drug use. This review will focus on upregulation of these receptors in adulthood, adolescence and development, as well as the findings from human genetic association studies which point to different roles for these receptors in risk for initiation and continuation of drug use.
Comparative studies on the chemical and enzymatic stability of alpha‐ and beta‐arbutin
Authors: Avonto C. , Wang Y.‐H. , Avula B. , Wang M. , Rua D. , Khan I. A.
Published: September 2015

Synopsis

Objective

The aim of this study was to establish a comparative analysis of the chemical and enzymatic stability of α‐ and β‐arbutins as potential sources of the substance of concern hydroquinone (HQ). The study was performed using an array of techniques including HPLC‐PDA, nuclear magnetic resonance (NMR) and optical rotation (OR). Both arbutins are emerging as popular and effective skin whiteners, acting as tyrosinase inhibitors in a fashion similar to the popular whitening agent HQ. Due to their structural similarity to the regulated agent HQ, both arbutins may be regarded as potential sources of the active aglycone after chemical or metabolic conversion.

Methods

Various cosmetic formulations including creams, sera, gels and lotions were analysed by HPLC‐PDA for their arbutin and HQ content in freshly opened and aged samples stored for 16 months. Solutions of pure compounds were also aged and periodically checked for degradation products using 1D and 2D NMR experiments and OR measurements. The metabolic stability was investigated using pear peels as a biological model.

Results

Both arbutins were found to be stable in water and methanol solutions in the absence of buffer or stabilizers. Their stability in cosmetic formulations, however, was found to depend on the type of formulation and pH. Both compounds were unstable under strong hydrolytic conditions, with consequent release of HQ. Enzymatic instability of both arbutins was also observed, although no formation of HQ was observed under the chosen experimental conditions.

Conclusion

Both arbutins were found to possess similar stability profiles, and to be more prone to in vivo rather than in chemico degradation, although no HQ was found after enzymatic hydrolysis. Also, no epimerization was observed in any of the tested conditions. Diverse experimental approaches can be applied to analyse the chemical and enzymatic stability of arbutins in regard to the potential release of HQ in different types of preparations. These result showed the potential use of NMR and OR as complementary investigative tools for the stability and safety assessment of arbutin along with more established HPLC methods.
A mixed method thematic review: the importance of hope to the dying patient
Authors: Broadhurst Kathleen , Harrington Ann
Published: September 2015

Aim

To review the literature and investigate the meaning of hope to patients receiving palliative care and to examine the themes that foster hope in those patients.

Background

Hope is often linked to the future and is a significant factor for patients dealing with adversity, such as a terminal illness. The concept of hope is underreported in the literature.

Design

Mixed method thematic review.

Data sources

CINAHL, Scopus, PsychINFO, Informit, PubMed, Science Direct, ProQuest, Web of Science and Google Scholar online databases were searched using keywords and inclusion and exclusion criteria published between 2003–2013.

Review methods

Twelve qualitative articles were thematically analysed using Braun and Clarke's () steps to ascertain major themes and sub‐themes. On analysis, the remaining three mixed method studies were found to reflect the themes generated by the qualitative studies.

Results

Seven key themes that increased hope were found: disease status; positive personal relationships; positive character traits; quality of life; setting and achieving goals; spirituality/religion; and hope after death.

Conclusion

The importance of hope to dying patients was established. Hope is a very complex and personal phenomena requiring hope‐enhancing strategies to be individualized. More research is needed with groups whose culture, youth or type of illness may affect their ability to foster and maintain hope.
From Framework to Practice: Person‐Directed Planning in the Real World
Authors: Martin Lynn , Grandia Philip , Ouellette‐Kuntz Hélène , Cobigo Virginie
Published: September 2015

Background

Person‐directed planning (PDP) is an approach to planning supports that aims to redistribute power from the service system to individuals with intellectual and developmental disabilities (IDD) and natural supports, improve relationships and build community. To do this, the right people with the right attitudes engaging in the right actions are needed. This paper examines how key elements in PDP contribute to successes in planning.

Materials/Methods

Researchers worked with three planning teams from different community service agencies using participatory action research techniques (i.e. free list and pile sort, Socratic wheel, whys/hows exercise).

Results

Most key elements of PDP were relevant to each team. Perceptions of which had most contributed to planning successes differed.

Conclusions

The various elements of PDP are used by and useful to planning teams, although some may be more relevant to some successes than others because of specific goals, or the person's strengths and needs.
Superinfection and the coevolution of parasite virulence and host recovery
Authors: Kada S. , Lion S.
Published: September 2015

Parasite strategies of host exploitation may be affected by host defence strategies and multiple infections. In particular, within‐host competition between multiple parasite strains has been shown to select for higher virulence. However, little is known on how multiple infections could affect the coevolution between host recovery and parasite virulence. Here, we extend a coevolutionary model introduced by van Baalen (Proc. R. Soc. B, 265, 1998, 317) to account for superinfection. When the susceptibility to superinfection is low, we recover van Baalen's results and show that there are two potential evolutionary endpoints: one with avirulent parasites and poorly defended hosts, and another one with high virulence and high recovery. However, when the susceptibility to superinfection is above a threshold, the only possible evolutionary outcome is one with high virulence and high investment into defence. We also show that within‐host competition may select for lower host recovery, as a consequence of selection for more virulent strains. We discuss how different parasite and host strategies (superinfection facilitation, competitive exclusion) as well as demographic and environmental parameters, such as host fecundity or various costs of defence, may affect the interplay between multiple infections and host–parasite coevolution. Our model shows the interplay between coevolutionary dynamics and multiple infections may be affected by crucial mechanistic or ecological details.
Factor structure and aetiological architecture of the BRIEF: A twin study
Authors: Little Callie W. , Taylor Jeanette , Moltisanti Allison , Ennis Chelsea , Hart Sara A. , Schatschneider Chris
Published: September 2015

Executive function is a broad construct that encompasses various processes involved in goal‐directed behaviour in non‐routine situations (Banich, 2009). The present study uses a sample of 560 5‐ to 16‐year‐old twin pairs (M = 11.14, SD = 2.53): 219 monozygotic twin pairs (114 female; 105 male) and 341 dizygotic twin pairs (136 female, 107 male; 98 opposite sex) to extend prior literature by providing information about the factor structure and the genetic and environmental architecture of the Behavior Rating Inventory of Executive Function (BRIEF; Gioia et al., 2000, Child Neuropsychol., 6, 235; Gioia et al., 2000, Behavior rating inventory of executive function, Lutz, FL: Psychological Assessment Resources), a multifaceted rating scale of everyday executive functions. Phenotypic results revealed a 9‐scale, 3‐factor model best represents the BRIEF structure within the current sample. Results of the genetically sensitive analyses indicated the presence of rater bias/contrast effects for the Initiate, Working Memory, and Task‐Monitor scales. Additive genetic and non‐shared environmental influences were present for the Initiate, Plan/Organize, Organization of Materials, Shift, and Monitor and Self‐Monitor scales. Influences on Emotional Control were solely environmental. Interestingly, the aetiological architecture observed was similar to that of performance‐based measures of executive function. This observed similarity provided additional evidence for the usefulness of the BRIEF as a measure of ‘everyday’ executive function.
Micro RNAs mir‐106a, mir‐122 and mir‐197 are increased in severe acute viral hepatitis with coagulopathy
Authors: Weseslindtner Lukas , Macheleidt Iris , Eischeid Hannah , Strassl Robert , Hofer Harald , Popow‐Kraupp Theresia , Dienes Hans‐Peter , Holzmann Heidemarie , Odenthal Margarete
Published: September 2015

Background & Aims

The severity of acute viral hepatitis, which may be caused by several distinct viruses, varies among individual patients. In rare cases, severe hepatic injury with sudden loss of liver function may occur, which is clinically indicated by the occurrence of coagulopathy or encephalopathy. As the molecular mechanisms of this liver injury are largely unknown, we investigated extracellular micro RNA (miRNA) profiles in 54 patients acutely infected with one of four different hepatotropic viruses, in order to identify those miRNAs which indicate severe viral hepatitis associated with coagulopathy.

Methods

First, the profile of miRNAs was extensively analysed using a microarray‐based approach in highly characterized 24 patients, matched in terms of sex, age and level of liver enzymes, as well as in three healthy controls. The cohort included samples from 18 patients with moderate and six individuals with severe hepatitis, indicated by abnormal prothrombin time and higher alanine aminotransferase and bilirubin levels. miRNAs found to be upregulated in severe hepatitis were then quantified by real‐time PCR in the expanded cohort of 54 patients.

Results

Comprehensive microarray‐based miRNA profiling identified upregulation of mir‐106a, mir‐122 and mir‐197 in patients with severe acute viral hepatitis with coagulopathy, as compared to patients who did not develop coagulopathy. mir‐106a, mir‐122 and mir‐197 were then proven to be significantly upregulated in patients with severe acute viral hepatitis by quantitative real‐time PCR (P < 0.01, Mann–Whitney U‐test).

Conclusions

mir‐106a, mir‐122 and mir‐197 could be potential markers for severe acute viral hepatitis associated with coagulopathy.
Splenectomy enhances the therapeutic effect of adipose tissue‐derived mesenchymal stem cell infusion on cirrhosis rats
Authors: Tang Wei‐Ping , Akahoshi Tomohiko , Piao Jing‐Shu , Narahara Sayoko , Murata Masaharu , Kawano Takahito , Hamano Nobuhito , Ikeda Tetsuo , Hashizume Makoto
Published: September 2015

Background & Aims

Clinical studies suggest that splenectomy improves liver function in cirrhotic patients, but the influence of splenectomy on stem cell transplantation is poorly understood. This study investigated the effect of splenectomy on stem cell infusion and elucidated its mechanism.

Methods

Rat adipose tissue‐derived mesenchymal stem cells were infused into cirrhosis rats with or without splenectomy, followed by the assessment of the in vivo distribution of stem cells and pathological changes. Stromal cell‐derived factor‐1 and hepatocyte growth factor expression were also investigated in splenectomized cirrhosis patients and rats.

Results

Splenectomy, prior to cell infusion, improved liver function and suppressed fibrosis progression more efficiently than cell infusion alone in the experimental cirrhosis model. Stromal cell‐derived factor‐1 and hepatocyte growth factor levels after splenectomy were increased in patients and rats. These upregulated cytokines significantly facilitated stem cell motility, migration and proliferation in vitro. C‐X‐C chemokine receptor type 4 neutralization weakened the promotion of cell migration by these cytokines. The infused cells integrated into liver fibrosis septa and participated in regeneration more efficiently in splenectomized rats. Direct coculture with stem cells led to inhibition of hepatic stellate cell proliferation. In addition, hepatocyte growth factor induced hepatic stellate cell apoptosis via the c‐jun N‐terminal kinase‐p53 pathway.

Conclusions

Splenectomy prior to cell infusion enhanced the therapeutic effect of stem cells on cirrhosis, which involved upregulation of stromal cell‐derived factor‐1 and hepatocyte growth factor after splenectomy.
Right Ventricular Angiogenesis is an Early Adaptive Response to Chronic Hypoxia‐Induced Pulmonary Hypertension
Authors: Kolb Todd M. , Peabody Jacelyn , Baddoura Philip , Fallica Jon , Mock Jason R. , Singer Benjamin D. , D'Alessio Franco R. , Damarla Mahendra , Damico Rachel L. , Hassoun Paul M.
Published: September 2015

Objective

Myocardial angiogenesis is presumed to play a role in RV adaptation to PH, though definitive evidence and functional correlations are lacking. We aimed to use definitive methods to correlate RV angiogenesis, hypertrophy, and function in a murine PH model.

Methods

Mice were exposed to CH for 21 days to induce PH and RV remodeling. We used unbiased stereology and flow cytometry to quantify angiogenesis and myocyte hypertrophy, and pressure–volume loops to measure RV function.

Results

Within seven days, RV‐specific increases in total capillary length (10,576 ± 2574 cm vs. 6822 ± 1379 cm; p = 0.02), surface area (10 ± 3.3 cm2 vs. 4.9 ± 1.5 cm2; p = 0.01), and volume (0.0013 ± 0.0005 cm3 vs. 0.0006 ± 0.0001 cm3; p = 0.02) were observed, and RV EC proliferation increased nearly 10‐fold. Continued exposure led to progressive RVH without additional angiogenesis. RV function was preserved, but activation of hypoxia‐dependent gene expression was observed in both ventricles after 21 days.

Conclusions

Early RV remodeling in CH‐PH is associated with RV angiogenesis and preserved RV function. Continued CH‐PH is associated with RVH but not angiogenesis, leading to biventricular activation of hypoxia‐dependent gene expression.
Teaching Collections Management Anthropologically
Authors: Krmpotich Cara
Published: September 2015

This article documents the creation of a teaching collection intended to teach and equally interrogate collections management practices and values to graduate‐level museum studies students. The collection is being used to convey to students the ways collections management is an embodied practice and an active area for research. The creation of the collection is discussed as an iterative process through the lens of material culture and museum anthropological analysis, taking into account the objects in the collection, the practices of collections management, and the interactions between students and the growing collection. The iterative process is likewise presented in waves of challenges and partial solutions. [collections management, material culture, museum anthropology]
Devil in The Digital: Ambivalent Results in an Object‐Based Teaching Course
Authors: Turin Mark
Published: September 2015

In 2013, I piloted a course in which students used Web‐based tools to explore underdocumented collections of Himalayan materials at Yale University. Through class‐based research and contextualization, I set students the goal of augmenting existing metadata and designing media‐rich, virtual tours of the collections that could be incorporated into the sparse catalogue holdings held within the library system. The process was experimental and had mixed results, as this article documents. The class provided an opportunity for undergraduate students from any discipline to work with objects and primary materials, requiring them to evaluate different sources of information, value, and legitimacy. Learning outcomes were nontraditional and intentionally underscripted. The collaborative and hands‐on approaches toward digitization that de‐emphasized the authority of the instructor were unsettling to some students. [digital humanities, mobile classroom, critical pedagogy, material culture, Himalaya]
Plastid genomes reveal support for deep phylogenetic relationships and extensive rate variation among palms and other commelinid monocots
Authors: Barrett Craig F. , Baker William J. , Comer Jason R. , Conran John G. , Lahmeyer Sean C. , Leebens‐Mack James H. , Li Jeff , Lim Gwynne S. , Mayfield‐Jones Dustin R. , Perez Leticia , Medina Jesus , Pires J. Chris , Santos Cristian , Wm. Stevenson Dennis , Zomlefer Wendy B. , Davis Jerrold I.
Published: September 2015

Despite progress based on multilocus, phylogenetic studies of the palms (order Arecales, family Arecaceae), uncertainty remains in resolution/support among major clades and for the placement of the palms among the commelinid monocots. Palms and related commelinids represent a classic case of substitution rate heterogeneity that has not been investigated in the genomic era.

To address questions of relationships, support and rate variation among palms and commelinid relatives, 39 plastomes representing the palms and related family Dasypogonaceae were generated via genome skimming and integrated within a monocot‐wide matrix for phylogenetic and molecular evolutionary analyses.

Support was strong for ‘deep’ relationships among the commelinid orders, among the five palm subfamilies, and among tribes of the subfamily Coryphoideae. Additionally, there was extreme heterogeneity in the plastid substitution rates across the commelinid orders indicated by model based analyses, with c. 22 rate shifts, and significant departure from a global clock.

To date, this study represents the most comprehensively sampled matrix of plastomes assembled for monocot angiosperms, providing genome‐scale support for phylogenetic relationships of monocot angiosperms, and lays the phylogenetic groundwork for comparative analyses of the drivers and correlates of such drastic differences in substitution rates across a diverse and significant clade.
Chemical tradeoffs in seed dispersal: defensive metabolites in fruits deter consumption by mutualist bats
Authors: Whitehead Susan R. , Quesada Maria F. Obando , Bowers M. Deane
Published: September 2015

Although fleshy fruits function primarily to attract seed dispersers, many animal‐dispersed fruits contain potentially toxic secondary metabolites. These metabolites can provide defense against seed predators and pathogens, but their effects on dispersers are still poorly understood. In some cases plants may experience a tradeoff, where the metabolites that provide fruit defense also reduce seed disperser preferences. In other cases the bioactivity of fruit secondary metabolites may be directed primarily at pests with no negative effects on seed‐dispersing vertebrates. We tested the effects of amides, a group of nitrogen‐based defensive compounds common in the plant genus Piper (Piperaceae), in interactions with the primary seed dispersers of Piper in the neotropics – fruit‐feeding bats in the genus Carollia (Phyllostomidae). In a series of flight cage experiments, pure amides and amide‐rich fruit extracts reduced the preferences of bats for Piper fruit, affecting both the bats’ initial choices to remove Piper infructescences and the proportion of fruit consumed from individual infructescences once they were removed. However, the effects of amides varied considerably among three species of Carollia and among the specific individual amides and extracts tested. Overall, our results support the hypothesis that plants experience a tradeoff between seed dispersal and fruit defense, but the strength of this tradeoff and the overall fitness consequences may depend strongly on ecological context.
Suicidal Zinc Phosphide Poisoning Unmasking Brugada Syndrome and Triggering Near Fatal Ventricular Arrhythmia
Authors: PRABHU MUKUND A. , AGUSTINUS REYNOLD , SHENTHAR JAYAPRAKASH
Published: September 2015

Brugada syndrome (BrS) is an inherited channelopathy associated with increased incidence of ventricular arrhythmias and has many acquired triggers. Zinc phosphide (ZnP) is a rodenticide and is commonly implicated in suicidal poison ingestion. ZnP poisoning can cause myocardial toxicity and death. We report a case of ZnP poisoning that triggered a type I Brugada pattern and ventricular fibrillation in a 67‐year‐old male. He had no other features of toxicity and recovered later. As metal phosphide is the commonest toxin involved in suicidal poisoning in India and BrS being endemic here, this case highlights an important clinical problem.
Reproductive failure in Arabidopsis thaliana under transient carbohydrate limitation: flowers and very young siliques are jettisoned and the meristem is maintained to allow successful resumption of reproductive growth
Authors: Lauxmann Martin A. , Annunziata Maria G. , Brunoud Géraldine , Wahl Vanessa , Koczut Andrzej , Burgos Asdrubal , Olas Justyna J. , Maximova Eugenia , Abel Christin , Schlereth Armin , Soja Aleksandra M. , Bläsing Oliver E. , Lunn John E. , Vernoux Teva , Stitt Mark
Published: September 2015

The impact of transient carbon depletion on reproductive growth in Arabidopsis was investigated by transferring long‐photoperiod‐grown plants to continuous darkness and returning them to a light–dark cycle. After 2 days of darkness, carbon reserves were depleted in reproductive sinks, and RNA in situ hybridization of marker transcripts showed that carbon starvation responses had been initiated in the meristem, anthers and ovules. Dark treatments of 2 or more days resulted in a bare‐segment phenotype on the floral stem, with 23–27 aborted siliques. These resulted from impaired growth of immature siliques and abortion of mature and immature flowers. Depolarization of PIN1 protein and increased DII‐VENUS expression pointed to rapid collapse of auxin gradients in the meristem and inhibition of primordia initiation. After transfer back to a light–dark cycle, flowers appeared and formed viable siliques and seeds. A similar phenotype was seen after transfer to sub‐compensation point irradiance or CO2. It also appeared in a milder form after a moderate decrease in irradiance and developed spontaneously in short photoperiods. We conclude that Arabidopsis inhibits primordia initiation and aborts flowers and very young siliques in C‐limited conditions. This curtails demand, safeguarding meristem function and allowing renewal of reproductive growth when carbon becomes available again.
Evaluation of the Percutaneous Absorption of Ketamine HCl, Gabapentin, Clonidine HCl, and Baclofen, in Compounded Transdermal Pain Formulations, Using the Franz Finite Dose Model
Authors: Bassani August S. , Banov Daniel
Published: September 2015

Objective. This study evaluates the ability of four commonly used analgesics (ketamine HCl, gabapentin, clonidine HCl, and baclofen), when incorporated into two transdermal compounding bases, Lipoderm and Lipoderm ActiveMax, to penetrate human cadaver trunk skin in vitro , using the Franz finite dose model.

Design. In vitro experimental study .

Methods. Ketamine HCl 5% w/w, gabapentin 10% w/w, clonidine HCl 0.2% w/w, and baclofen 2% w/w were compounded into two transdermal bases, Lipoderm and Lipoderm ActiveMax. Each compounded drug formulation was tested on skin from three different donors and three replicate skin sections per donor. The Franz finite dose model was used in this study to evaluate the percutaneous absorption and distribution of drugs within each formulation.

Results. Rapid penetration to peak flux was detected for gabapentin and baclofen at approximately 1 hour after application. Clonidine HCl also had a rapid penetration to peak flux occurring approximately 1 hour after application and had a secondary peak at approximately 40 hours. Ketamine HCl exhibited higher overall absorption rates than the other drugs, and peaked at 6–10 hours. Similar patterns of drug distribution within the skin were also observed using both transdermal bases.

Conclusions. This study suggests that the combination of these 4 analgesic drugs can be successfully delivered transdermally, using either Lipoderm or Lipoderm ActiveMax. Compounded transdermal drug preparations may then provide physicians with an alternative to traditional oral pain management regimens that can be personalized to the specific patient with the potential for enhanced pain control.
Hearing Voices in Different Cultures: A Social Kindling Hypothesis
Authors: Luhrmann Tanya M. , Padmavati R. , Tharoor Hema , Osei Akwasi
Published: September 2015

This study compares 20 subjects, in each of three different settings, with serious psychotic disorder (they meet inclusion criteria for schizophrenia) who hear voices, and compares their voice‐hearing experience. We find that while there is much that is similar, there are notable differences in the kinds of voices that people seem to experience. In a California sample, people were more likely to describe their voices as intrusive unreal thoughts; in the South Indian sample, they were more likely to describe them as providing useful guidance; and in our West African sample, they were more likely to describe them as morally good and causally powerful. What we think we may be observing is that people who fall ill with serious psychotic disorder pay selective attention to a constant stream of many different auditory and quasi‐auditory events because of different “cultural invitations”—variations in ways of thinking about minds, persons, spirits and so forth. Such a process is consistent with processes described in the cognitive psychology and psychiatric anthropology literature, but not yet described or understood with respect to cultural variations in auditory hallucinations. We call this process “social kindling.”
Mixed-Mode Signal Detection of Road Vehicle Vibration Using Hilbert-Huang Transform
Authors: Lepine Julien , Sek Michael , Rouillard Vincent
Published: September 2015

The Hilbert-Huang Transform (HHT) is a fully adaptive time-frequency analysis method which is applicable to nonlinear and nonstationary processes. However, this promising method is fairly new and its range of applications is not well known. Furthermore, its mathematical framework is not yet fully developed. So far, the HHT has yielded interesting results for many applications such as biomedical, geophysical, meteorological and health monitoring, but there is no evidence of its application on complex mixed-mode vibration signals. To fill that gap, this paper investigates the application of the HHT to detect the different modes of road vehicle vibration signals. These modes originate from road roughness variation and vehicle speed which create nonstationary random vibration. Other modes are due to road surface aberrations which create transient events and the engine and drive train system of the vehicle which create harmonic vibrations. The energy density/average period significance test based on the HHT is assessed to detect these modes. The results, based on purposefully created synthetic test signals, reveal the limitations and shortcomings of the HHT based technique to detect and separate the various components of the mixed-mode vibration signals such as vehicle vibration signal.
Determination of the Bearing Quality by Means of Vibroacoustic Response
Authors: Ziaran Stanislav , Musil Milos , Chlebo Ondrej
Published: September 2015

A signal of mechanical and acoustical vibration generated during a bearing’s quality testing contains variety of useful information about their operational conditions. At defined testing speeds, the bearings generate a periodical and a non-periodical vibroacoustic signal of different intensities, which are dependent on the quality of bearings and/or their damage type. A dynamical response of the tested bearings recorded in time characterizes also the nature of the unwanted noise of bearings. Therefore the dynamical response of the maximum acceleration recorded in time is one of the major criteria of bearing quality evaluation in terms of noisiness. The second criterion is a determination of statistically significant frequency interval for the equivalent acceleration value expressed in decibels. Consequently, from the effective acceleration value, the bearing quality can be determined in terms of its vibration severity, as well as its noise level. This objective methodology substitutes the evaluation bearing quality by means of measurement of the vibration acceleration on the given test device and simultaneously evaluation of the noise quality and its intensity auditorily. Verifying the proposed methodology 100 % conformity was achieved between the methodology currently used and the new methodology, which eliminates the subjective quality evaluation of bearings auditorily.
Characterization of Low Noise Technologies Applied to a Full Scale Fuselage Mounted Nose Landing Gear
Authors: Neri Eleonora , Kennedy John , Bennett Gareth J.
Published: September 2015

The negative impact of aircraft noise includes effects on population’s health, land use planning and economic issues such as building restrictions and operating restrictions for airports. Thus, the reduction of noise generated by aircraft at take-off and approach is an essential consideration in the development of new commercial aircraft. Among the different aircraft noise sources, landing gear noise is one of the most significant during approach. This research presents results from the European Clean Sky funded ALLEGRA project, which investigated a full-scale Nose Landing Gear (NLG) model featuring the belly fuselage, bay cavity and hydraulic dressing. Tests were performed for a variety of wind speeds and yaw angles. In this paper, a characterization of the noise generated by the full-scale Nose Landing Gear (NLG) model is presented and the different techniques used for characterizing acoustic sources on the NLG are described. The landing gear noise source is characterized in terms of OASPL, directivity, source spectra, PNL and PNLT. A comparison between the NLG with and without the application of low noise technology is presented.
Vibration Control of Variable Thickness Plates With Embedded Acoustic Black Holes and Dynamic Vibration Absorbers
Authors: Jia Xiuxian , Du Yu , Zhao Kunmin
Published: September 2015

In the past decade, plate-like structures embedded with one or more acoustic black hole (ABH) features have been developed as a promising passive approach for structural sound and vibration control. In this study, the concept of combining dynamic vibration absorbers (DVAs) and the ABH effect is proposed to further improve the vibration control effectiveness of a variable thickness plate. A finite element (FE) model is developed to analyze the vibration response of a plate embedded with both ABHs and DVAs under point force excitations. To demonstrate the effectiveness of different vibration control approaches, the vibration responses of plates of uniform thickness, variable thickness embedded with ABH features, variable thickness embedded with both ABH features and damping layers, and variable thickness embedded with both ABH features and DVAs are compared experimentally. It is shown that, in the frequency range considered in the current study which is up to 6.4 kHz, the uniform plate presents high average velocity response level. On the other hand, although 11.5% lighter, the variable thickness plate integrated with both ABH and DVA features results in the lowest response level. Results in this study demonstrate the potential of combing DVAs and ABHs together as an effective lightweight noise and vibration control approach.
System-Level Vibration Testing of Physical Hardware Components Using Real-Time Hybrid Substructuring
Authors: Botelho Rui M. , Franco Joseph A. , Christenson Richard E.
Published: September 2015

Real-time hybrid substructuring (RTHS) is a relatively new method of vibration testing for characterizing the system-level performance of physical hardware components. With RTHS, a dynamic system is partitioned into physical and numerical substructures and interfaced together in real-time similar to hardware-in-the-loop testing. This paper presents an overview of RTHS including the challenges posed by its real-time constraints and the application to system-level testing of physical vibration control devices and mechanical equipment. Two laboratory RTHS experiments performed at the University of Connecticut Structures Research Laboratory are used to demonstrate the benefit of RTHS. The first test examines the connected control method using viscous damper hardware as the physical substructure coupled to adjacent base isolation systems as the numerical substructure. The second test involves a multi-stage isolation system comprised of an operating mechanical component on isolators as the physical substructure coupled to an intermediate mass on similar isolators as the numerical substructure. In these RTHS tests, feedforward inverse compensation combined with feedback is used to compensate the frequency-dependent dynamics of the multi-actuator system. Experimental results demonstrate that RTHS accurately captures the system-level behavior of the coupled system and allows for repeatable tests of various conditions and potential system improvements to be efficiently examined.
Density functional theory studies on Cs activation mechanism between GaN (0001) and Al0.25Ga0.75N (0001) surface
Authors: Shen Yang , Chen Liang , Dong Yanyan , Zhang Shuqin , Xu Sunan , Qian Yunsheng
Published: September 2015

In order to study the influence of Al fraction at the AlxGa1−xN photocathode, models of GaN (0001) and Al0.25Ga0.75N (0001) surfaces are built and compared. Plane wave with ultrasoft pseudopotential method based on first-principle density functional theory is used to calculate and compare the Cs activation mechanism for Al0.25Ga0.75N (0001) surface and GaN (0001) surface. In this work, seven possible Cs adsorption sites are chosen for the Al0.25Ga0.75N (0001) surface while five high-symmetry sites are considered in the calculation model of GaN (0001) surface. Adsorption energy, work function, surface dipole moment, and photocurrent curves are obtained. Results show that Cs adsorption lowers the surface work function and benefits to get the most stable adsorption sites. To verify the result of our calculations, an activation experiment is performed on p-type Mg-doped GaN and AlGaN substrate grown by metal organic chemical vapor deposition. The photocurrent curves show that the overall photocurrent value of GaN photocathode is greater than that of Al0.25Ga0.75N photocathode. Spectral response curves of two photocathodes are also investigated and used to explain the difference of photocurrent. This works gives a reference for the further experimental research on the AlxGa1−xN and GaN photocathodes.
Monte Carlo reference data sets for imaging research: Executive summary of the report of AAPM Research Committee Task Group 195
Authors: Sechopoulos Ioannis , Ali Elsayed S. M. , Badal Andreu , Badano Aldo , Boone John M. , Kyprianou Iacovos S. , Mainegra‐Hing Ernesto , McMillan Kyle L. , McNitt‐Gray Michael F. , Rogers D. W. O. , Samei Ehsan , Turner Adam C.
Published: September 2015

The use of Monte Carlo simulations in diagnostic medical imaging research is widespread due to its flexibility and ability to estimate quantities that are challenging to measure empirically. However, any new Monte Carlo simulation code needs to be validated before it can be used reliably. The type and degree of validation required depends on the goals of the research project, but, typically, such validation involves either comparison of simulation results to physical measurements or to previously published results obtained with established Monte Carlo codes. The former is complicated due to nuances of experimental conditions and uncertainty, while the latter is challenging due to typical graphical presentation and lack of simulation details in previous publications. In addition, entering the field of Monte Carlo simulations in general involves a steep learning curve. It is not a simple task to learn how to program and interpret a Monte Carlo simulation, even when using one of the publicly available code packages. This Task Group report provides a common reference for benchmarking Monte Carlo simulations across a range of Monte Carlo codes and simulation scenarios. In the report, all simulation conditions are provided for six different Monte Carlo simulation cases that involve common x‐ray based imaging research areas. The results obtained for the six cases using four publicly available Monte Carlo software packages are included in tabular form. In addition to a full description of all simulation conditions and results, a discussion and comparison of results among the Monte Carlo packages and the lessons learned during the compilation of these results are included. This abridged version of the report includes only an introductory description of the six cases and a brief example of the results of one of the cases. This work provides an investigator the necessary information to benchmark his/her Monte Carlo simulation software against the reference cases included here before performing his/her own novel research. In addition, an investigator entering the field of Monte Carlo simulations can use these descriptions and results as a self‐teaching tool to ensure that he/she is able to perform a specific simulation correctly. Finally, educators can assign these cases as learning projects as part of course objectives or training programs.
Monte Carlo simulations of the dose from imaging with GE eXplore 120 micro‐CT using gate
Authors: Bretin Florian , Bahri Mohamed Ali , Luxen André , Phillips Christophe , Plenevaux Alain , Seret Alain
Published: September 2015

Purpose:

Small animals are increasingly used as translational models in preclinical imaging studies involving microCT, during which the subjects can be exposed to large amounts of radiation. While the radiation levels are generally sublethal, studies have shown that low‐level radiation can change physiological parameters in mice. In order to rule out any influence of radiation on the outcome of such experiments, or resulting deterministic effects in the subjects, the levels of radiation involved need to be addressed. The aim of this study was to investigate the radiation dose delivered by the GE eXplore 120 microCT non‐invasively using Monte Carlo simulations in gate and to compare results to previously obtained experimental values.

Methods:

Tungsten X‐ray spectra were simulated at 70, 80, and 97 kVp using an analytical tool and their half‐value layers were simulated for spectra validation against experimentally measured values of the physical X‐ray tube. A Monte Carlo model of the microCT system was set up and four protocols that are regularly applied to live animal scanning were implemented. The computed tomography dose index (CTDI) inside a PMMA phantom was derived and multiple field of view acquisitions were simulated using the PMMA phantom, a representative mouse and rat.

Results:

Simulated half‐value layers agreed with experimentally obtained results within a 7% error window. The CTDI ranged from 20 to 56 mGy and closely matched experimental values. Derived organ doses in mice reached 459 mGy in bones and up to 200 mGy in soft tissue organs using the highest energy protocol. Dose levels in rats were lower due to the increased mass of the animal compared to mice. The uncertainty of all dose simulations was below 14%.

Conclusions:

Monte Carlo simulations proved a valuable tool to investigate the 3D dose distribution in animals from microCT. Small animals, especially mice (due to their small volume), receive large amounts of radiation from the GE eXplore 120 microCT, which might alter physiological parameters in a longitudinal study setup.