bluuebunny/crossref_metadata_2025 huggingface dataset:
A General Method for Detecting Interference Between Units in Randomized Experiments
Authors: Aronow Peter M.
Published: June 2012

Interference between units may pose a threat to unbiased causal inference in randomized controlled experiments. Although the assumption of no interference is often necessary for causal inference, few options are available for testing this assumption. This article presents an ex post method for detecting interference between units in randomized experiments. With a test statistic of the analyst’s choice, a conditional randomization test allows for the calculation of the exact significance level of the causal dependence of outcomes on the treatment status of other units. The robustness of the method is demonstrated through simulation studies. Moreover, using this method, interference between units is detected in a field experiment designed to assess the effect of mailings on voter turnout in a U.S. primary election.
Dealing With Incomplete Household Panel Data in Inequality Research
Authors: Frick Joachim R. , Grabka Markus M. , Groh-Samberg Olaf
Published: June 2012

In trying to capture complete within-household heterogeneity, household panel surveys typically try to interview all adult household members. Following from this, such surveys tend to suffer from partial unit nonresponse (PUNR), that is, the nonresponse of at least one member of an otherwise participating household, most likely yielding an underestimation of aggregate household income. Using data from the German Socio-Economic Panel (SOEP), the authors evaluate four different strategies to deal with this phenomenon: (a) ignorance, that is, assuming the missing individual’s income to be zero; (b) adjustment of the equivalence scale to account for differences in household size and composition; (c) elimination of all households observed to suffer PUNR and reweighting of households observed to be at risk of but not affected by PUNR; and (d) longitudinal imputation of the missing income components. The aim of this article is to show how the choice of technique affects substantive results in inequality research. The authors find indications of substantial bias on income inequality and poverty as well as on income mobility.
An Activity for Demonstrating the Concept of a Neural Circuit
Authors: Kreiner David S.
Published: June 2012

College students in two sections of a general psychology course participated in a demonstration of a simple neural circuit. The activity was based on a neural circuit that Jeffress proposed for localizing sounds. Students in one section responded to a questionnaire prior to participating in the activity, while students in the other section responded to the questionnaire after participating in the activity. Students who had participated in the activity reported greater understanding of the concept of a neural circuit and of how the brain can produce complex behavior. The activity may be a useful addition to previously published class simulations on neural functioning. Instructors may wish to use the activity in classes such as general psychology, sensation and perception, and physiological psychology.
“What Makes a Woman a Woman?” Versus “Our First Lady of Sport”
Authors: Cooky Cheryl , Dycus Ranissa , Dworkin Shari L.
Published: June 2012

Caster Semenya, a South African female track and field star from rural Limpopo South Africa, won the IAAF 2009 World Championships in the 800-meter event. She was then subjected to “gender-verification” testing. Media reports, especially in the United States, underscored that Semenya underwent gender-verification testing because of her “deep voice, muscular build, and rapid improvement in times.” Combining content and textual analysis, we conducted a comparative media analysis of the Caster Semenya controversy in the United States and the South African print news media. Results demonstrated that the United States print media coverage framed the controversy in terms of Semenya’s “true” sex, “medicalized” debates about sex testing, and discussed the limitations of medical assessment of male and female bodies in sport. In comparison, South African print media sources focused on human rights, nationalism, and “strategic essentialism” to frame Semenya as a “true” woman defending the nation against a perceived racist assault. We conclude the article with transformative visions of sport rooted in postcolonial feminism and critical feminist studies.
Functional Connectivity Networks in Nonbothersome Tinnitus
Authors: Wineland Andre M. , Burton Harold , Piccirillo Jay
Published: June 2012

Objective

To assess functional connectivity in cortical networks in patients with nonbothersome tinnitus compared with a normal healthy nontinnitus control group by measuring low‐frequency (<0.1 Hz) spontaneous blood oxygenation level–dependent (BOLD) signals at rest.

Design

Case‐control.

Setting

Academic medical center.

Participants

Nonbothersome, idiopathic subjective tinnitus for at least 6 months (n = 18) and a normal healthy nontinnitus control group (n = 23).

Main Outcome Measure

Functional connectivity differences in 58 a priori selected seed regions of interest encompassing cortical loci in the default mode, attention, auditory, visual, somatosensory, and cognitive networks.

Results

The median age of the 18 subjects was 54 years (interquartile range [IQR], 52‐57), 66% were male, 90% were white, median Tinnitus Handicap Inventory (THI) score was 8 (IQR, 4‐14), and a median Beck Depression Index score was 1 (IQR, 0‐5). The median age for the control group was 46 years (IQR, 39‐54), and 52% were male. Of the 58 seeds analyzed, no regions had significantly different functional connectivity among the nonbothersome tinnitus group when compared with the control group.

Conclusion

Among nonbothersome tinnitus patients, the tinnitus percept does not appear to alter the functional connectivity of the auditory cortex or other key cortical regions.

Trial Registration

ClinicalTrials.gov Identifier: NCT01049828
Understanding preprint sharing on Sciencepaper Online from the perspectives of motivation and trust
Authors: Zha Xianjin , Li Jing , Yan Yalan
Published: June 2012

The objective of this study is to explore preprint sharing in the context of quick sharing of scientific papers through the lens of knowledge sharing, which is largely overlooked by the previous literature. In this study, we developed a research model from the perspectives of motivation and trust basing on the Theory of Reasoned Action. We carried out an online survey of authors who had contributed their preprints to the Chinese preprint system, Sciencepaper Online. The results showed that trust is the key determinant of Attitude towards preprint sharing, while Anticipated Extrinsic Reward impacts both Image and Sense of Self-Worth which further impact Attitude. Attitude and Subjective Norm both impact Intention. These findings and their implications for theory and practice are discussed. We believe that the current research usefully contributes to the theoretical development of the structural model concerning quick sharing of preprints both in the specific context of Sciencepaper Online and other quick sharing platforms more generally, and also provide useful insights into and helpful suggestions for Chinese preprint sharing practice.
Effects of naltrexone on food intake and body weight gain in olanzapine-treated rats
Authors: Kurbanov Daniel B , Currie Paul J , Simonson Donald C , Borsook David , Elman Igor
Published: June 2012

Blockade of opioidergic neurotransmission contributes to reduction in body weight. However, how such blockade affects body weight gain (BWG) attributed to second generation antipsychotic agents (SGAs) has not yet been established. Here we examined the effects of an opioid receptor antagonist, naltrexone (NTX), on food intake and BWG associated with an SGA, olanzapine (OL). Four groups of Wistar Han IGS rats were treated for 28 days with either OL (2 mg/kg twice daily, intraperitoneal (IP)), a combination of OL (2 mg/kg twice daily, IP) + extended-release NTX (50 mg/kg, one-time, intramuscular (IM)), extended-release NTX (50 mg/kg, one-time, IM) or vehicle and their food intake and body weight were measured daily for the first nine days and every other day thereafter. Food intake and BWG that were increased by OL were decreased by the added NTX while NTX alone had no significant effects on food intake or on BWG. Plasma leptin concentrations were significantly elevated in the three groups receiving pharmacological agents, but did not differ among each other, suggesting that changes in leptin secretion and/or clearance alone would not explain the food intake and the body weight findings. Our results extend prior reports on anorexigenic effects of opioid antagonists by demonstrating that such effects may generalize to food intake increases and BWG arising in the context of OL pharmacotherapy.
Health Care Reform
Authors: Wald Richard M. , Patel Shailey S.
Published: June 2012

Health care reform is rather complicated and confusing, but it also represents an opportunity for employers to create competitive advantages. The CHRO dilemma, whether to “pay” or “play,” has a number of resulting Talent implications. The human resources function is at the epicenter of a major disruption that can go either way for an organization. Mishandling the question of health benefits can carry a big price tag in dollars, reputation, competitiveness or some combination of the three. Handled correctly, the opportunity to craft a new approach to health care can position a company as an employer of choice and make it more competitive in the market.
Birth-Cohort Effects in the Association Between Personality and Fertility
Authors: Jokela Markus
Published: June 2012

The present study investigated whether associations between individuals’ personality traits and whether they have children have been modified by birth-cohort effects in the 20th-century United States. Participants were from the Midlife Development in the United States study ( n = 6,259) and the Wisconsin Longitudinal Study ( n = 3,994) and were born between 1914 and 1974. Data on personality traits of the Five Factor model and fertility history were collected in adulthood. Higher levels of openness to experience in both sexes and higher levels of conscientiousness in women were associated with lower fertility, and these associations strengthened linearly as birth cohorts became younger. In the total sample, high extraversion, low neuroticism, and women’s high agreeableness were associated with high fertility rate, but there were no systematic cohort effects. The fertility decisions of people with certain personality traits may be influenced by prevailing societal and cultural circumstances.
Hermeneutics of continuity: Theorizing psychological understandings of ancient literature
Authors: Baydala Angelina , Smythe William E.
Published: June 2012

This paper theorizes how ancient literature can be used to inspire contemporary psychological understanding. We articulate a critical presentism that reads ancient literature symbolically without losing sight of important differences of meaning over time. Although ancient literature may inspire understanding of our present-day concerns, historical text cannot be used to explain contemporary understandings without charges of naïve presentism. A hermeneutics of archetypes is used to theorize a way of using ancient literature that remains critical of presentist claims to knowledge. Without losing sight of important socio-historical differences, the story of The Bacchae is used to illustrate how literature from the past can engender psychological understanding.
Squamous Metaplasia of the Peritoneum
Authors: Mrklić Ivana , Bendić Antonia , Pogorelić Zenon , Karaman Ivana , Glavina Durdov Merica , Družijanić Nikica , Tomić Snježana
Published: June 2012

The ability of the peritoneum to undergo metaplasia, especially to Müllerian-type epithelium has been recognized for a long time. The ability of mesothelial cells to modulate cytoskeletal filaments and shape is provided through the distinct form of subserosal cells, called multipotential subserosal cells, that have the function of replicative cells that differentiate into surface epithelium when affected by various stimuli. Rare forms of peritoneal metaplasia include squamous and cartilaginous metaplasia. This report presents a case of fully developed, mature peritoneal squamous metaplasia in an 85-year-old woman who underwent surgery because of small bowel perforation leading to diffuse peritonitis. This rare incidental finding almost always occurs in the background of chronic peritoneal irritation as a response to mesothelial injury. Squamos peritoneal metaplasia should not be interpreted as metastatic squamous cell carcinoma. The most important distinguishing criteria are the lack of nuclear atypia, mitoses, necrosis, and desmoplastic stromal response.
Preclinical Safety, Pharmacokinetics, and Pharmacodynamics of Recombinant Human Interleukin-21 in Cynomolgus Macaques (Macaca fascicularis)
Authors: Waggie Kimberly S. , Holdren Matthew S. , Byrnes-Blake Kelly , Pedersen Susan , Ponce Rafael , Hughes Steven , Miller Dennis M.
Published: June 2012

Interleukin-21 (IL-21), a pleiotropic immunostimulatory type I cytokine, has anticancer effects in animal models. Preclinical studies designed to assess the safety of recombinant human IL-21 (rIL-21) for use in phase I oncology studies are described. The rIL-21 (≤3.0 mg/kg per dose) was given intravenously to cynomolgus monkeys ( Macaca fascicularis) once daily for 5 days, followed by 9 nondosing days (1 cycle) for ≤4 cycles. The rIL-21 pharmacokinetics was dose-dependent. Accumulation was not observed after repeated dosing, consistent with the short elimination half-life ( t1/2,λz; 0.4-0.8 hours). Safety findings included cyclical anemia and thrombocytopenia, clinical pathology changes consistent with acute-phase response, leukocyte infiltrates in hepatic sinusoids, and sporadic serum transaminase elevations (typically <3 times upper-limit of normal); all were reversible upon cessation of treatment. Decreased pharmacodynamic responses with time corresponded to the development of anti-rIL-21 antibodies; effects varied among individuals and were dose-dependent. These studies demonstrated rIL-21 to be generally well-tolerated when administered to cynomolgus monkeys, and all adverse effects were reversible upon treatment cessation. However, development of anti-rIL-21 antibodies may limit the use of this species in long-term studies.
Acute exacerbation of multiple sclerosis presenting with facial metamorphopsia and palinopsia
Authors: Anbarasan Deepti , Howard Jonathan
Published: June 2012

We discuss the case of a patient with a known history of relapsing–remitting multiple sclerosis (MS) who presented with the isolated complaint of altered visual perception in the absence of abnormalities on ophthalmological examination. To the best of the authors’ knowledge, this is the first documented case of both facial metamorphopsia and palinopsia occurring as the symptoms of demyelinating brain lesions consistent with an acute MS exacerbation. These symptoms appear to be related to active demyelination that either involved the optic radiations in the visual pathway or the visual association area in the temporo-occipital region of the left hemisphere.
Epistemological boot camp: The politics of science and what every qualitative researcher needs to know to survive in the academy
Authors: Staller Karen M.
Published: June 2012

Doctoral students and faculty members sometimes face unexpected barriers when engaging in qualitative research that can impede career advancement. In part, this can be because qualitative methodologies often conflict with objectivist epistemological assumptions that are deeply embedded in university cultures. Since ontology, epistemology, methodology, and methods are related, it is imperative for qualitative researchers to understand these differences and recognize the resulting tensions. Furthermore, when conducting qualitative research it is critical to design studies in which the epistemology, methodology, and methods are logically integrated for the best quality work. In this article, I seek to make transparent the link between everyday problems that arise (in dissertation defenses, funding and Institutional Review Board applications, peer review, tenure and promotion, etc.) and the underlying epistemological and methodological issues that produce them. I seek to educate beginning qualitative researchers about the importance of this integration in their own work and to arm them with some diagnostic skills. In doing so they will be better prepared to successfully negotiate the politics of science, the politics of evidence, and the politics of methods within their home institutions.
Pilot Study of a New Model for Managing Hypertension in an Uninsured Population
Authors: Sanders James , Guse Clare , Onuoha Berthrand C.
Published: June 2012

For millions of uninsured Americans who have hypertension, quality medical care is too expensive to access with any regularity. The Community-based Chronic Disease Management (CCDM) Clinic was created to deliver clinical care for medically uninsured patients in a setting of low resources and high need. CCDM’s model melds nurse-led teams with the chronic disease model and uses evidence-based clinical decision protocols. This new model of care differs from traditional models. CCDM conducted a nonrandomized prospective trial of the effectiveness of this new model of care. The intervention included free education, medications, and laboratory investigations. For hypertensives treated for 6 months and 1 year, national benchmark goals were reached for 45% (50/110, P < .00005) and 56% (43/77, P < .00005) of patients, respectively, compared with 18% and 22% being at goal at initial presentation. The CCDM model may have implications for health service delivery in insured populations as well. Further study is warranted.
Enforced expression of Lin28b leads to impaired T-cell development, release of inflammatory cytokines, and peripheral T-cell lymphoma
Authors: Beachy Sarah H. , Onozawa Masahiro , Chung Yang Jo , Slape Chris , Bilke Sven , Francis Princy , Pineda Marbin , Walker Robert L. , Meltzer Paul , Aplan Peter D.
Published: June 2012

LIN28A and LIN28B, the mammalian homologs of lin-28, are implicated in malignant transformation in part because of their ability to promote degradation of the let-7 family of miRs. In the present study, we show that overexpression of Lin28b in vivo leads to an aggressive peripheral T-cell lymphoma (PTCL) characterized by widespread infiltration of parenchymal organs with malignant CD4+ cells. Similar to patients with PTCL, Lin28b-transgenic mice show signs of inflammation such as eosinophilia, increased C-reactive protein, release of inflammatory cytokines, and pleural effusion. The PTCLs that develop in Lin28b mice are derived from activated T cells and show decreased let-7 expression, increased Il6 expression, activation of NF-κB, and infiltration of B cells, all resulting in an inflammatory microenvironment. In addition, LIN28B is overexpressed 7.5-fold in PTCL patient samples compared with activated CD4+ cells. The results of the present study demonstrate for the first time that Lin28b can transform primary cells in vivo, identify a previously unsuspected link between Lin28b and PTCL, and provide a unique animal model for the study of PTCL biology and therapy.
Anti-CD3ε mAb improves thymic architecture and prevents autoimmune manifestations in a mouse model of Omenn syndrome: therapeutic implications
Authors: Marrella Veronica , Poliani Pietro L. , Fontana Elena , Casati Anna , Maina Virginia , Cassani Barbara , Ficara Francesca , Cominelli Manuela , Schena Francesca , Paulis Marianna , Traggiai Elisabetta , Vezzoni Paolo , Grassi Fabio , Villa Anna
Published: June 2012

Omenn syndrome (OS) is an atypical primary immunodeficiency characterized by severe autoimmunity because of activated T cells infiltrating target organs. The impaired recombinase activity in OS severely affects expression of the pre-T-cell receptor complex in immature thymocytes, which is crucial for an efficient development of the thymic epithelial component. Anti-CD3ε monoclonal antibody (mAb) treatment in RAG2−/− mice was previously shown to mimic pre-TCR signaling promoting thymic expansion. Here we show the effect of anti-CD3ε mAb administration in the RAG2R229Q mouse model, which closely recapitulates human OS. These animals, in spite of the inability to induce the autoimmune regulator, displayed a significant amelioration in thymic epithelial compartment and an important reduction of peripheral T-cell activation and tissue infiltration. Furthermore, by injecting a high number of RAG2R229Q progenitors into RAG2−/− animals previously conditioned with anti-CD3ε mAb, we detected autoimmune regulator expression together with the absence of peripheral immunopathology. These observations indicate that improving epithelial thymic function might ameliorate the detrimental behavior of the cell-autonomous RAG defect. Our data provide important therapeutic proof of concept for future clinical applications of anti-CD3ε mAb treatment in severe combined immunodeficiency forms characterized by poor thymus function and autoimmunity.
Stat3: linking inflammation to epithelial cancer - more than a "gut" feeling?
Authors: Jarnicki Andrew , Putoczki Tracy , Ernst Matthias
Published: June 2012

Inflammation is an important environmental factor that promotes tumourigenesis and the progression of established cancerous lesions, and recent studies have started to dissect the mechanisms linking the two pathologies. These inflammatory and infectious conditions trigger immune and stromal cell release of soluble mediators which facilitate survival and proliferation of tumour cells in a paracrine manner. In addition, (epi-)genetic mutations affecting oncogenes, tumour-suppressor genes, chromosomal rearrangements and amplifications trigger the release of inflammatory mediators within the tumour microenvironment to promote neoplastic growth in an autocrine manner. These two pathways converge in tumour cells and result in activation of the latent signal transducer and activator of transcription 3 (Stat3) which mediates a transcriptional response favouring survival, proliferation and angiogenesis. The abundance of cytokines that activate Stat3 within the tumour microenvironment, which comprises of members of the interleukin (IL) IL6, IL10 and IL17/23 families, underpins a signaling network that simultaneously promotes the growth of neoplastic epithelium, fuels inflammation and suppresses the host's anti-tumour immune response. Accordingly, aberrant and persistent Stat3 activation is a frequent observation in human cancers of epithelial origin and is often associated with poor outcome.

Here we summarize insights gained from mice harbouring mutations in components of the Stat3 signaling cascade and in particular of gp130, the shared receptor for the IL6 family of cytokines. We focus on the various feed-back and feed-forward loops in which Stat3 provides the signaling node in cells of the tumour and its microenvironment thereby functionally linking excessive inflammation to neoplastic growth. Although these observations are particularly pertinent to gastrointestinal tumours, we suggest that the tumour's addiction to persistent Stat3 activation is likely to also impact on other epithelial cell-derived cancers. These insights provide clues to the judicious interference of the gp130/Stat3 signaling cascade in therapeutically targeting cancer.
Inverting surface GPR data using FDTD simulation and automatic detection of reflections to estimate subsurface water content and geometry
Authors: Buchner Jens S. , Wollschläger Ute , Roth Kurt
Published: June 2012

A new inversion scheme for common-offset ground-penetrating radar measurements at multiple antenna separations was proposed, which is intermediate between inverting of picked reflectors using ray-tracing and full-waveform inversion. The measurements are modeled similarly to the real data using 2D finite-difference time-domain simulations. These simulations are obtained with a parameterized model of the subsurface that consists of several layers with constant dielectric permittivity and an explicit representation of the layers’ interfaces. Then, reflections in the modeled and in the real data are detected automatically, and the reflections of interest of the real data are selected manually. The sum of squared residuals of the reflections’ traveltime and amplitude is iteratively minimized to estimate subsurface water content and geometry, i.e., the position and shape of the layer interfaces. The method was first tested with a synthetic data set and then applied to a real data set. The comparison of the method’s result with ground-truth data showed an agreement with the subsurface geometry within [Formula: see text] and with the water content, a difference less than [Formula: see text] volume.
Bandwidth enhancement: Inverse Q filtering or time-varying Wiener deconvolution?
Authors: van der Baan Mirko
Published: June 2012

Dispersion and attenuation corrections can improve the resolution of seismic data. This significantly facilitates interpretation. In principle, inverse [Formula: see text] filtering and the time-varying Wiener deconvolution can achieve this. Inverse [Formula: see text] filtering is a deterministic process that requires knowledge of the quality factor [Formula: see text], whereas the time-varying Wiener deconvolution is a statistical approach based on the estimation of the nonstationary propagating wavelet. Dispersion corrections based on phase-only inverse [Formula: see text] filtering is an inherently stable method that is robust in the presence of noise. Attenuation corrections via amplitude-only inverse [Formula: see text] filtering, on the other hand, is likely to lead to noise amplification as well as bandwidth enhancement. Dispersion corrections via the time-varying Wiener deconvolution are challenging because these require estimation of a nonstationary, frequency-dependent, nonminimum-phase wavelet. Fortunately, attenuation corrections via the Wiener deconvolution need only estimation of a zero-phase time-varying wavelet for which robust methods exist. The most promising procedure for combined dispersion and attenuation correction is thus comprised of first applying dispersion corrections using phase-only inverse [Formula: see text] filtering, followed by zero-phase time-varying Wiener deconvolution.
Ovarian Function and Reproductive Hormone Levels in Girls with Prader-Willi Syndrome: A Longitudinal Study
Authors: Siemensma Elbrich P. C. , van Alfen-van der Velden A. A. E. M. (Janielle) , Otten Barto J. , Laven Joop S. E. , Hokken-Koelega Anita C. S.
Published: June 2012

Context:

The etiology of hypogonadism in girls with Prader-Willi syndrome (PWS) remains uncertain.

Objectives:

The aim of the study was to evaluate gonadal function longitudinally in girls and female adolescents with PWS.

Measurements:

We performed a longitudinal assessment of anti-Müllerian hormone (AMH), gonadotropins, estradiol (E2), inhibin B and A, and pubertal development in girls and female adolescents with PWS.

Patients and Methods:

Sixty-one girls participating in the Dutch PWS Cohort study participated in the study. Serum AMH, gonadotropins, E2, and inhibin B and A levels were compared with reference values.

Results:

AMH levels in girls and female adolescents with PWS were comparable to reference levels between 6 months and 22 yr of age. From 10 yr of age, FSH and LH levels increased to above the 5th percentile compared to reference levels. E2 and inhibin B levels were in the low normal range in the majority, and inhibin A levels were low but detectable in almost half the female adolescents with PWS. The median age at puberty onset was comparable, but the median ages at attaining Tanner M3 (P = 0.05) and M4 (P < 0.0001) were significantly higher in girls with PWS than in healthy references.

Conclusion:

Our study shows that the primordial follicle pool and number of small antral follicles are conserved in girls and female adolescents with PWS. We found no classical hypogonadotropic hypogonadism. However, maturation of follicles and progression of pubertal development are impaired, which might be due to dysregulation of LH secretion. Because these impairments are not absolute, ovulation and thus conception cannot be ruled out in individual female adolescents with PWS.
Regulatory role for a conserved motif adjacent to the homeodomain of Hox10 proteins
Authors: Guerreiro Isabel , Casaca Ana , Nunes Andreia , Monteiro Sara , Nóvoa Ana , Ferreira Ricardo B. , Bom Joana , Mallo Moisés
Published: June 2012

Development of the vertebrate axial skeleton requires the concerted activity of several Hox genes. Among them, Hox genes belonging to the paralog group 10 are essential for the formation of the lumbar region of the vertebral column, owing to their capacity to block rib formation. In this work, we explored the basis for the rib-repressing activity of Hox10 proteins. Because genetic experiments in mice demonstrated that Hox10 proteins are strongly redundant in this function, we first searched for common motifs among the group members. We identified the presence of two small sequences flanking the homeodomain that are phylogenetically conserved among Hox10 proteins and that seem to be specific for this group. We show here that one of these motifs is required but not sufficient for the rib-repressing activity of Hox10 proteins. This motif includes two potential phosphorylation sites, which are essential for protein activity as their mutation to alanines resulted in a total loss of rib-repressing properties. Our data indicates that this motif has a significant regulatory function, modulating interactions with more N-terminal parts of the Hox protein, eventually triggering the rib-repressing program. In addition, this motif might also regulate protein activity by alteration of the protein's DNA-binding affinity through changes in the phosphorylation state of two conserved tyrosine residues within the homeodomain.
Chemical Biology of Natural Products on the Basis of Identification of Target Proteins
Authors: Ueda Minoru
Published: June 2012

Recent progress in chemical biology research has accelerated the target protein identification of biologically active small molecules, including naturally occurring ligands. It is widely recognized that a biologically active natural product functions as a “key” that fits a specific protein “lock.” However, recent studies have revealed multiligandable nature of natural products that works as “multiple keys” (or a “master key”) fitting multiple “locks” in a biological event. Biological experiments using natural products as ligands have often provided puzzling results, which can likely be attributed to their multiligandability. Thus, a novel research direction dealing with multiliganbale natural product ligand based on their target identification is strongly desired. This review focuses on the current status of natural products chemistry based on their target identification, and suggest the future direction, named chemical biological chemistry (Chem-Bio-Chem).
Synthesis of Triple-ringed [14]Arene via Dynamic Covalent Chemistry Mechanism in Condensation Reaction of Phenols with m-Benzenedicarbaldehyde
Authors: Seki Hiroyuki , Kuwabara Shingo , Kudo Hiroto , Nishikubo Tadatomi
Published: June 2012

Condensation reaction of 2-methylresorcinol with m-benzenedicarbaldehyde in the presence of HCl as a catalyst in n-propanol at 90 °C for 48 h proceeded via a dynamic covalent chemistry (DCC) mechanism to afford a triple-ringed [14]arene in 52% yield.
Epidemiology of end-stage renal disease in the countries of the Gulf Cooperation Council: a systematic review
Authors: Hassanien Amal A. , Al-Shaikh Fahdah , Vamos Eszter P. , Yadegarfar Ghasem , Majeed Azeem
Published: June 2012

Objectives

To describe the epidemiology of end stage renal disease (ESRD).

Design

Mixed-methods systematic review.

Setting

The countries of the Gulf Cooperation Council (GCC) which consist of Saudi Arabia, the United Arab Emirates, Kuwait, Qatar, Bahrain, and Oman.

Participants

Defined to have ESRD or patients on regular dialysis for a minimum dialysis period of at least three months. Since many outcomes were reviewed, studies that estimated the incidence and prevalence of ESRD as outcomes should not have defined the study population as ESRD population or patients on regular dialysis. Studies where the study population mainly comprised children or pregnant woman were excluded.

Main outcome measures

The trends of the incidence, prevalence, and mortality rate of ESRD; also, causes of mortality, primary causes and co-morbid conditions associated with ESRD.

Results

44 studies included in this review show that the incidence of ESRD has increased while the prevalence and mortality rate of ESRD in the GCC has not been reported sufficiently. The leading primary causes of ESRD recorded in the countries of the GCC is diabetes with the most prevalent co-morbid conditions being Hypertension and Hepatitis C Virus infection; the most common cause of death was cardiovascular disease and sepsis.

Conclusions

This review highlights that the lack of national renal registries data is a critical issue in the countries of the GCC. The available data also do not provide an accurate and updated estimate for relevant outcomes. Additionally, considering the increasing burden of chronic kidney disease (CKD), these results stressed the needs and the importance of preventative strategies for leading causes of ESRD. Furthermore, more studies are needed to describe the epidemiology of ESRD and for assessing the overall quality of renal care.
Thrombus load and acute right ventricular failure in pulmonary embolism: correlation and demonstration of a “tipping point” on CT pulmonary angiography
Authors: Wong L F , Akram A R , Mcgurk S , Van Beek E J R , Reid J H , Murchison J T
Published: June 2012

Objectives

The aim of this study was to determine the correlation between increasing pulmonary embolism thrombus load and right ventricular (RV) dilatation as demonstrated by CT pulmonary angiography (CTPA) and to assess the thrombus load threshold which indicates impending RV decompensation.

Methods

2425 consecutive CTPAs were retrospectively analysed. Thrombus load using a modified Miller score (MMS), RV to left ventricular (RV:LV) ratio, presence of septal shift, and pulmonary artery and aorta size were analysed in 504 positive CTPA scans and a representative cohort of 100 negative scans. Results were correlated using non-parametric analysis (two-tailed t-test or χ  2 test) and Pearson’s rank correlation.

Results

Increasing thrombus load correlated with a higher RV:LV ratio, with a statistically significant difference in RV:LV ratios between the negative and positive pulmonary embolism (PE) cohorts. Larger thrombus loads (MMS ≥12 vs MMS <12) were strongly correlated with RV strain (mean RV:LV ratio, 1.323 vs 0.930; p<0.0001). Smaller thrombus loads had no significant influence on RV strain. Septal shift was also more likely with an MMS of ≥12, as was an increase in pulmonary artery diameter (r=0.221, p<0.001).

Conclusion

With increasing thrombus load in PE, there is CTPA evidence of RV decompensation with an MMS threshold of 12. This suggests a “tipping point” beyond which RV decompensation is more likely to occur. This is the first study to describe this tipping point between a thrombus load of MMS >12 and an increase in RV:LV ratio. This finding may help to improve risk stratification in patients with acute PE diagnosed by CTPA.
Transient Stability Constrained Line-Flow-Based Optimal Power Flow Analysis
Authors: Uzoechi Lazarus O. , Mahajan Satish M. , Radman Ghadir
Published: June 2012

This paper establishes a new method that adopts the line-flow-based (LFB) approach to develop a transient stability constrained optimal power flow (OPF) analysis called LFB-TSCOPF. The transient energy function (TEF) serves as a direct means of carrying out the stability analysis. The reduction technique was adopted in which the classical machine model was reduced to the internal node model. The proposed method was tested on the WECC 9-bus, three-machine, IEEE 14-bus, five-machine, and the New England 39-bus, ten-machine test systems. The results were compared with other known results from different methods in literature. The results of the active power and total optimal costs are quite promising and consistent with other known methods. The LFB-TSCOPF re-dispatches real power by applying the energy margin performance index as an indication of the generator unit(s) to be rescheduled. The LFB-TSCOPF provides a more comprehensive linear model, reduces computation time and can be useful for online stability studies.
New Method for Assessment of Distributed Generation Impact on Distribution System Reliability: Islanded Operation
Authors: Abdullah Ahmad
Published: June 2012

Distributed Generation “DG” is an emerging technology which is receiving mush attention and studies. One of the most important aspects of DG is reliability. Reliability is defined as the ability of the system to deliver electrical power to the customers within various limits. These limits include limits on continuity of supply, voltage drop, sag, regulation and other limits which are mentioned in various standards. This paper focuses on solving some problems with the reliability modeling of DGs [1]. Existing algorithms which deal with DG are very complex due to the nature of the model of the DG itself [1]. Some of the protection algorithms have to be complex so that they do not to count the DG twice [2]. In this paper protection algorithms and set of equations are proposed to accurately model the DG and calculate its effect on Load point indices. Then the method is applied to a study case to illustrate the steps needed to calculate the load point indices [3]. A load flow result will be used to determine the size of the DG needed. The system which will be studied is a system where the DG serves an island or what is known as islanded operation of DG [4]. The method only applies to islanded operation and cannot be used for other modes of operation of the DG. The results show that a very accurate method could be used to model the DG without the need for complex, time consuming algorithms which a characteristic of the existing algorithms. This paper presents the role of the DG in improving the system reliability by proposing a new method for calculation of load point indices in the case of DG presence in the system. The method is then applied to a study case.
Nano- and microstructures in stretched and non-stretched blend gels of cellulose and hemicelluloses
Authors: Roubroeks Johannes P. , Kondo Tetsuo
Published: June 2012

Molecular interactions between cellulose and hemicelluloses, such as xyloglucan and xylan, play an important role in the formation of ordered layers in the cell wall of higher plants. This study attempts to characterize an ordered state of a matrix consisting of cellulose and hemicellulose induced by stretching never-dried binary blended films. In non-stretched films, the xylan component easily adapted into the semicrystalline state, while the xyloglucan component remained amorphous. Once both blended films were stretched, each component tended to be close enough to the adherent macromolecule, and the interaction resulted in typical morphological orders at the nano- and microscale levels. These studies could be useful in constructing new bio-derived materials, as well as understanding the molecular interactions between the polymers.
Pretreatment of softwood dissolving pulp with ionic liquids
Authors: Li Dongfang , Sevastyanova Olena , Ek Monica
Published: June 2012

Few Scandinavian pulp mills produce dissolving pulps; however, the demand on textile fibers is increasing. This study investigates the chemical interaction of dissolving pulp with ionic liquids (ILs), where softwood and hardwood industrial dissolving pulps were pretreated with ILs 1-butyl-3-methy-limidazolium acetate ([C4mim+]CH3COO-) and 1-butyl-3-methyl-imdazolium chloride ([C4mim+]Cl-). Time and temperature dependence of the dissolution process as well as the impact of the pretreatment on the molecular weight properties, thermal stability, morphology, and crystallinity of the cellulose were evaluated by means of size exclusion chromatography (SEC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), X-ray diffraction (XRD), and solid state nuclear magnetic resonance (NMR). It was shown that the dissolution of cellulosic material in ILs is a temperature-dependent process; however, the viscosity of ILs affected the efficiency of dissolution at a given temperature. Molecular weight properties were affected negatively by increased dissolution temperature, while the type of antisolvent for the regeneration had no major impact on the degree of polymerization of cellulose. Water was more efficient than ethanol for the regeneration of cellulose when performed at an elevated temperature. The pretreatment decreased the crystallinity of cellulosic material. This might lead to the increased accessibility and reactivity of cellulose.
A posteriori error analysis for unstable models
Authors: Bakushinsky Anatoly B. , Smirnova Alexandra , Liu Hui
Published: June 2012

In this paper, we consider the possibility of a posteriori error estimates for linear and nonlinear ill-posed operator equations.
Given an auxiliary finite-dimensional problem ,
that approximates the original infinite model , with a certain level of accuracy,
we try to estimate the distance between z, an approximate solution to , and , the exact solution to . The problem
is assumed to accumulate different sources of error (discretization, measurements, etc.), and the computed solution z is assumed to satisfy the equation
within a nonzero tolerance .
We conduct both a theoretical and numerical study of a posteriori error analysis.
The ontogeny of the endocrine pancreas in the fetal/newborn baboon
Authors: Quinn Amy R , Blanco Cynthia L , Perego Carla , Finzi Giovanna , La Rosa Stefano , Capella Carlo , Guardado-Mendoza Rodolfo , Casiraghi Francesca , Gastaldelli Amalia , Johnson Marney , Dick Edward J , Folli Franco
Published: June 2012

Erratic regulation of glucose metabolism including hyperglycemia is a common condition in premature infants and is associated with increased morbidity and mortality. The objective of this study was to examine histological and ultrastructural differences in the endocrine pancreas in fetal (throughout gestation) and neonatal baboons. Twelve fetal baboons were delivered at 125 days (d) gestational age (GA), 140d GA, or 175d GA. Eight animals were delivered at term (185d GA); half were fed for 5 days. Seventy-three nondiabetic adult baboons were used for comparison. Pancreatic tissue was studied using light microscopy, confocal imaging, and electron microscopy. The fetal and neonatal endocrine pancreas islet architecture became more organized as GA advanced. The percent areas of α-β-δ-cell type were similar within each fetal and newborn GA (NS) but were higher than the adults (P<0.05) regardless of GA. The ratio of β cells within the islet (whole and core) increased with gestation (P<0.01). Neonatal baboons, which survived for 5 days (feeding), had a 2.5-fold increase in pancreas weight compared with their counterparts killed at birth (P=0.01). Endocrine cells were also found in exocrine ductal and acinar cells in 125, 140 and 175d GA fetuses. Subpopulation of tissue that coexpressed trypsin and glucagon/insulin shows the presence of cells with mixed endo–exocrine lineage in fetuses. In summary, the fetal endocrine pancreas has no prevalence of a α-β-δ-cell type with larger endocrine cell percent areas than adults. Cells with mixed endocrine/exocrine phenotype occur during fetal development. Developmental differences may play a role in glucose homeostasis during the neonatal period and may have long-term implications.
Safety of Intra-Articular Use of Atelocollagen for Enhanced Tissue Repair
Authors: Magarian Elise M , Vavken Patrick , Connolly Susan A , Mastrangelo Ashley N , Murray Martha M
Published: June 2012

Collagen is an important biomaterial in intra-articular tissue engineering, but there are unanswered questions about its safety. We hypothesize that the addition of type-I-collagen for primary repair of the Anterior Cruciate Ligament (ACL) might result in a local and systemic reaction in a porcine model after 15 weeks as demonstrated by joint effusion, synovial thickening, elevated intraarticular and systemic leukocyte counts. Further, this reaction might be aggravated by the addition of a platelet concentrate. Eighteen porcine ACLs were transected and repaired with either sutures (n=6), a collagen sponge (n=6), or a collagen-platelet-composite (CPC; n=6). Twelve intact contralateral knees served as controls (n=12). No significant synovial thickening or joint effusion was seen in the collagen-treated knees. Synovial fluid leukocyte counts showed no significant differences between surgically treated and intact knees, and no differences were seen in leukocyte counts of the peripheral blood. The addition of a platelet concentrate to the knee joint resulted in lower serum levels of IL-1β, but serum levels of TNF-α were not significantly different between groups. In conclusion, the presence of collagen, with or without added platelets, did not increase the local or systemic inflammatory reactions following surgery, suggesting that Type I collagen is safe to use in the knee joint.
A Pragmatic Approach to More Efficient Corporate Disclosure
Authors: Bloomfield Robert J.
Published: June 2012

SYNOPSIS

This paper uses a Pragmatic theory of language (drawn from philosophy and linguistics) to diagnose the causes of excessive financial disclosure and propose a regulatory solution. The diagnosis is that existing disclosure regulations are one sided, effectively encouraging firms to disclose any information that might be relevant, but failing to discourage disclosure of information that adds little to what investors already know. This one-sidedness limits investors' ability to draw inferences that items the firm chooses not to disclose are not newsworthy (an inference Pragmatic theorists call “implicature”). The solution is to encourage or require firms to supplement comprehensive disclosures with an “elevated” disclosure that is brief enough to force firms to be selective in choosing what information to include. Regulations can enhance implicature through rules that prohibit firms from elevating disclosures that are less newsworthy than disclosures that are not elevated.
The Role of Accounting in the Financial Crisis: Lessons for the Future
Authors: Kothari S. P. , Lester Rebecca
Published: June 2012

SYNOPSIS

The advent of the Great Recession in 2008 was the culmination of a perfect storm of lax regulation, a growing housing bubble, rising popularity of derivatives instruments, and questionable banking practices. In addition to these causes, management incentives as well as certain U.S. accounting standards contributed to the financial crisis. We outline the significant effects of these incentive structures and the role of fair value accounting standards during the crisis, and discuss implications and relevance of these rules to practitioners, standard-setters, and academics.