bluuebunny/crossref_metadata_2025 huggingface dataset:
Differential Prognosis of Isolated Cortical Swelling and Hypoattenuation on CT in Acute Stroke
Authors: Butcher Kenneth S. , Lee Sang Bong , Parsons Mark W. , Allport Louise , Fink John , Tress Brian , Donnan Geoffrey , Davis Stephen M.
Published: February 2007

Background and Purpose—

The Alberta Stroke Program Early CT Score (ASPECTS) is a validated method of assessing parenchymal ischemic changes, including focal swelling and hypoattenuation. The hypothesis that these signs result from different pathophysiological processes was tested by comparing CT with diffusion and perfusion- weighted MRI.

Methods—

MRI and CT were performed, within 2 hours of each other, in 30 ischemic stroke patients <17 hours after symptom onset. Relative apparent diffusion coefficient, relative cerebral blood flow, and relative cerebral blood volume were calculated for individual cortical ASPECTS regions. Regional infarction was assessed on days 3 to 5.

Results—

Isolated focal swelling was seen in 25 ASPECTS cortical regions from 6 patients. Cortical hypoattenuation was observed in 25 regions from 11 patients. Median relative apparent diffusion coefficient was significantly lower in hypoattenuated regions (0.84; interquartile range, 0.66 to 0.91) relative to those with focal swelling (0.97; interquartile range, 0.91 to 1.01;
P
<0.001). Median relative cerebral blood flow in focal swelling regions (81.0%; interquartile range, 70.4 to 93.0) was similar to that of tissue that appeared normal on CT (71.8%; interquartile range, 47.1 to 94.5). In hypoattenuated regions, relative cerebral blood flow was significantly decreased (37.0%; interquartile range, 25.6 to 70.2;
P
=0.002). Median relative cerebral blood volume was increased (121.1%; interquartile range, 112.0 to 130.3) in focal swelling regions, relative to normal-appearing tissue (94.7%; interquartile range, 62.0 to 114.6;
P
<0.001), but decreased in hypoattenuated regions (58.9%; interquartile range, 47.5 to 92.7;
P
=0.012). Infarction occurred in all hypoattenuated regions, but only in 32% of those with focal swelling.

Conclusions—

Elevated relative cerebral blood volume and normal relative apparent diffusion coefficient in ASPECTS regions with focal swelling on CT is consistent with penumbral tissue. Isolated focal swelling is not always associated with infarction. These results support removal of focal swelling from the ASPECTS system.
Historicizing a Racialized Jesus: Case Studies in the "Black Christ," the "Mestizo Christ," and White Critique
Authors: Siker Jeffrey
Published: February 2007

This article examines the interaction between the quest for the historical Jesus in modern biblical scholarship and contemporary theologies in which race and ethnicity play a major role. While ideologies of race have certainly been formative of modern biblical scholarship, such scholarship has in turn had an important influence on the construction of various modern Jesuses, where race becomes the determinative contemporary marker for articulating the continuing reality of the historical Jesus. This essay looks at how modern biblical scholarship has contributed to the historicizing and retrojection of a racialized Jesus. In particular, two case studies of such historicizing racialization are presented: Jesus as the "black Christ," and Jesus as the "mestizo Christ." The focus here is on the important work of James Cone and Virgilio Elizondo, with attention to how the historical Jesus is idealized with a "black" or "mestizo" identity. The essentializing character of historical Jesus studies provides a springboard for Cone's parallel essentializing of Jesus as "black" while Elizondo's Hegelianesque portrait of Jesus as the "mestizo" bridge between the borderlands of Jewish and Gentile territory relies on modern biblical scholarship's construction of the historical Jesus as somehow the synthesis of both Galilean peasant and urban Greek sophisticate. Finally, attention is devoted to the role of white privilege and "white critique" when it comes to racializing the historical Jesus.
Seasonal Variability of the South Equatorial Current Bifurcation in the Atlantic Ocean: A Numerical Study
Authors: Rodrigues Regina R. , Rothstein Lewis M. , Wimbush Mark
Published: February 2007

In this study, a reduced-gravity, primitive equation OGCM is used to investigate the seasonal variability of the bifurcation of the South Equatorial Current (SEC) into the Brazil Current (BC) to the south and the North Brazil Undercurrent/Current (NBUC/NBC) system to the north. Annual mean meridional velocity averaged within a 2° longitude band off the South American coast shows that the SEC bifurcation occurs at about 10°–14°S near the surface, shifting poleward with increasing depth, reaching 27°S at 1000 m, in both observations and model. The bifurcation latitude reaches its southernmost position in July (∼17°S in the top 200 m) and its northernmost position in November (∼13°S in the top 200 m). The model results show that most of the seasonal variability of the bifurcation latitude in the upper thermocline is associated with changes in the local wind stress curl due to the annual north–south excursion of the marine ITCZ complex. As the SEC bifurcation latitude moves south (north) the NBUC transport increases (decreases) and the BC transport decreases (increases). The remote forcing (i.e., westward propagation of anomalies) appears to have a smaller impact on the seasonal variability of the bifurcation in the upper thermocline.
Long-term T-cell reconstitution after hematopoietic stem-cell transplantation in primary T-cell–immunodeficient patients is associated with myeloid chimerism and possibly the primary disease phenotype
Authors: Cavazzana-Calvo Marina , Carlier Frédérique , Le Deist Françoise , Morillon Estelle , Taupin Pierre , Gautier David , Radford-Weiss Isabelle , Caillat-Zucman Sophie , Neven Bénédicte , Blanche Stephane , Cheynier Rémi , Fischer Alain , Hacein-Bey-Abina Salima
Published: February 2007

We studied T-cell reconstitution in 31 primary T-cell–immunodeficient patients who had undergone hematopoietic stem-cell transplantation (HSCT) over 10 years previously. In 19 patients, there was no evidence of myeloid chimerism because little or no myeloablation had been performed. Given this context, we sought factors associated with good long-term T-cell reconstitution. We found that all patients having undergone full myeloablation had donor myeloid cells and persistent thymopoiesis, as evidenced by the presence of naive T cells carrying T-cell receptor excision circles (TRECs). In 9 patients with host myeloid chimerism, sustained thymic output was also observed and appeared to be associated with γc deficiency. It is therefore possible that the complete absence of thymic progenitors characterizing this condition created a more favorable environment for thymic seeding by a population of early progenitor cells with the potential for self-renewal, thus enabling long-term (> 10 years) T-cell production.
PD-1 up-regulation is correlated with HIV-specific memory CD8+ T-cell exhaustion in typical progressors but not in long-term nonprogressors
Authors: Zhang Ji-Yuan , Zhang Zheng , Wang Xicheng , Fu Jun-Liang , Yao Jinxia , Jiao Yanmei , Chen Liangen , Zhang Hui , Wei Jianan , Jin Lei , Shi Ming , Gao George Fu , Wu Hao , Wang Fu-Sheng
Published: February 2007

The immunoreceptor PD-1 is significantly up-regulated on exhausted CD8+ T cells during chronic viral infections such as HIV-1. However, it remains unknown whether PD-1 expression on CD8+ T cells differs between typical progressors (TPs) and long-term nonprogressors (LTNPs). In this report, we examined PD-1 expression on HIV-specific CD8+ T cells from 63 adults with chronic HIV infection. We found that LTNPs exhibited functional HIV-specific memory CD8+ T cells with markedly lower PD-1 expression. TPs, in contrast, showed significantly up-regulated PD-1 expression that was closely correlated with a reduction in CD4 T-cell number and an elevation in plasma viral load. Importantly, PD-1 up-regulation was also associated with reduced perforin and IFN-γ production, as well as decreased HIV-specific effector memory CD8+ T-cell proliferation in TPs but not LTNPs. Blocking PD-1/PD-L1 interactions efficiently restored HIV-specific CD8+ T-cell effector function and proliferation. Taken together, these findings confirm the hypothesis that high PD-1 up-regulation mediates HIV-specific CD8+ T-cell exhaustion. Blocking the PD-1/PD-L1 pathway may represent a new therapeutic option for this disease and provide more insight into immune pathogenesis in LTNPs.
Regulation of Growth Hormone Signaling by Selective Estrogen Receptor Modulators Occurs through Suppression of Protein Tyrosine Phosphatases
Authors: Leung Kin-Chuen , Brce Jesena , Doyle Nathan , Lee Heather J. , Leong Gary M. , Sjögren Klara , Ho Ken K. Y.
Published: February 2007

Activation of the Janus kinase 2 (JAK2)/signal transducer and activator of transcription 5 (STAT5) pathway by GH is terminated by the suppressors of cytokine signaling (SOCSs) and protein tyrosine phosphatases, Src homology 2 domain-containing protein tyrosine phosphatase (SHP)-1 and SHP-2. Based on our recent report that estrogen inhibits GH signaling by stimulating SOCS-2 expression, we investigated the effects of selective estrogen receptor modulators (SERMs) on GH signaling in human embryonic kidney (HEK293) and breast cancer (MDA-MB-231) cells expressing human GH receptor and estrogen receptor-α. 17β-Estradiol (E2) suppressed GH activation of a STAT5-responsive luciferase reporter and JAK2 phosphorylation in both cell models. 4-Hydroxytamoxifen and raloxifene augmented these actions of GH in HEK293 cells but not breast cancer cells. SOCS-2 expression in both cell types was stimulated by E2 but unaffected by SERMs. In HEK293 cells, SHP-1 was inhibited by raloxifene and 4-hydroxytamoxifen, whereas the latter additionally inhibited SHP-2. The phosphatases were unaffected by E2. In breast cancer cells, phosphatase activity was not altered by SERMs or E2. In summary, estrogen inhibited the JAK2/STAT5 signaling of GH and stimulated SOCS-2 expression in both HEK293 and breast cancer cells. By contrast, SERMs augmented GH signaling by reducing SHP activities in HEK293 cells and had no effect on both in breast cancer cells. We provide the first evidence for a novel mechanism regulating GH signaling, in which SERMs enhance GH activation of the JAK2/STAT5 pathway in a cell-type-dependent manner by attenuating protein tyrosine phosphatase activities.
A Novel Inhibitory Protein in Adipose Tissue, the Aldo-Keto Reductase AKR1B7: Its Role in Adipogenesis
Authors: Tirard Julien , Gout Johann , Lefrançois-Martinez Anne Marie , Martinez Antoine , Begeot Martine , Naville Danielle
Published: February 2007

The aldo-keto reductase 1B7 (AKR1B7) encodes an aldose-reductase that has been reported as a detoxification enzyme until now. We have demonstrated that AKR1B7 is differently expressed in various mouse white adipose tissues depending on their location. Its expression is associated with a higher ratio of preadipocytes vs. adipocytes. The cells that express AKR1B7 did not contain lipid droplets, and the expression level of akr1b7 was very low in mature adipocytes. We have defined the role of AKR1B7 in adipogenesis using either primary cultures of adipose stromal cells (containing adipocyte precursors) or the 3T3-L1 cell line. Under the same differentiation conditions, adipose stromal cells from tissues that expressed AKR1B7 had a decreased capacity to accumulate lipids compared with those that did not express it. Moreover, the overexpression of sense or antisense AKR1B7 in 3T3-L1 preadipocytes inhibited or accelerated, respectively, their rate of differentiation into adipocytes. In vivo experiments demonstrated that AKR1B7-encoding mRNA expression decreased in adipose tissues from mice where obesity was induced by a high-fat diet. All these results attributed for the first time a novel role to AKR1B7, which is the inhibition of adipogenesis in some adipose tissues.
Midgut epithelial endocrine cells are a rich source of the neuropeptides APSGFLGMRamide (Cancer borealis tachykinin-related peptide Ia) and GYRKPPFNGSIFamide (Gly1-SIFamide) in the crabs Cancer borealis, Cancer magister and Cancer productus
Authors: Christie Andrew E. , Kutz-Naber Kimberly K. , Stemmler Elizabeth A. , Klein Alexandra , Messinger Daniel I. , Goiney Christopher C. , Conterato Anna J. , Bruns Emily A. , Hsu Yun-Wei A. , Li Lingjun , Dickinson Patsy S.
Published: February 2007

Over a quarter of a century ago, Mykles described the presence of putative endocrine cells in the midgut epithelium of the crab Cancer magister(Mykles, 1979). In the years that have followed, these cells have been largely ignored and nothing is known about their hormone content or the functions they play in this species. Here,we used a combination of immunohistochemistry and mass spectrometric techniques to investigate these questions. Using immunohistochemistry, we identified both SIFamide- and tachykinin-related peptide (TRP)-like immunopositive cells in the midgut epithelium of C. magister, as well as in that of Cancer borealis and Cancer productus. In each species, the SIFamide-like labeling was restricted to the anterior portion of the midgut, including the paired anterior midgut caeca, whereas the TRP-like immunoreactivity predominated in the posterior midgut and the posterior midgut caecum. Regardless of location, label or species, the morphology of the immunopositive cells matched that of the putative endocrine cells characterized ultrastructurally by Mykles(Mykles, 1979). Matrix-assisted laser desorption/ionization-Fourier transform mass spectrometry identified the peptides responsible for the immunoreactivities as GYRKPPFNGSIFamide (Gly1-SIFamide) and APSGFLGMRamide [Cancer borealis tachykinin-related peptide Ia (CabTRP Ia)], respectively, both of which are known neuropeptides of Cancer species. Although the function of these midgut-derived peptides remains unknown, we found that both Gly1-SIFamide and CabTRP Ia were released when the midgut was exposed to high-potassium saline. In addition, CabTRP Ia was detectable in the hemolymph of crabs that had been held without food for several days, but not in that of fed animals, paralleling results that were attributed to TRP release from midgut endocrine cells in insects. Thus, one function that midgut-derived CabTRP Ia may play in Cancer species is paracrine/hormonal control of feeding-related behavior, as has been postulated for TRPs released from homologous cells in insects.
Empathy or Antipathy? The Impact of Diversity
Authors: Boisjoly Johanne , Duncan Greg J , Kremer Michael , Levy Dan M , Eccles Jacque
Published: February 2007

Mixing across racial and ethnic lines could spur understanding or inflame tensions between groups. We find that white students at a large state university randomly assigned African American roommates in their first year were more likely to endorse affirmative action and view a diverse student body as essential for a high-quality education. They were also more likely to say they have more personal contact with, and interact more comfortably with, members of minority groups. Although sample sizes are too small to provide definitive evidence, these results suggest students become more empathetic with the social groups to which their roommates belong.
The Homecoming of American College Women: The Reversal of the College Gender Gap
Authors: Goldin Claudia , Katz Lawrence F , Kuziemko Ilyana
Published: February 2007

Women are currently the majority of U.S. college students and of those receiving a bachelor's degree, but were 39 percent of undergraduates in 1960. We use three longitudinal data sets of high school graduates in 1957, 1972, and 1992 to understand the narrowing of the gender gap in college and its reversal. From 1972 to 1992 high school girls narrowed the gap with boys in math and science course taking and in achievement test scores. These variables, which we term the proximate determinants, can account for 30 to 60 percent of the relative increase in women's college completion rate. Behind these changes were several others: the future work expectations of young women increased greatly between 1968 and 1979 and the age at first marriage for college graduate women rose by 2.5 years in the 1970s, allowing them to be more serious students. The reversal of the college gender gap, rather than just its elimination, was due in part to the persistence of behavioral and developmental differences between males and females.
How Richard Nixon Pressured Arthur Burns: Evidence from the Nixon Tapes
Authors: Abrams Burton A
Published: February 2007

Evidence from the Nixon tapes, now available to researchers, shows that President Richard Nixon pressured the chairman of the Federal Reserve, Arthur Burns, to engage in expansionary monetary policies in the run-up to the 1972 election. This paper quotes the relevant conversations from the Nixon tapes. Questions remain as to whether Burns followed an expansionary policy in an already-inflationary environment out of conviction or because of political pressure.
The Macroeconomist as Scientist and Engineer
Authors: Mankiw N. Gregory
Published: February 2007

The subfield of macroeconomics was born, not as a science, but more as a type of engineering. The problem that gave birth to our field was the Great Depression. God put macroeconomists on earth not to propose and test elegant theories but to solve practical problems. This essay offers a brief history of macroeconomics, together with an evaluation of what we have learned. My premise is that the field has evolved through the efforts of two types of macroeconomists—those who understand the field as a type of engineering and those who would like it to be more of a science. While the early macroeconomists were engineers trying to solve practical problems, the macroeconomists of the past several decades have been more interested in developing analytic tools and establishing theoretical principles. These tools and principles, however, have been slow to find their way into applications. As the field of macroeconomics has evolved, one recurrent theme has been the interaction—sometimes productive and sometimes not— between the scientists and the engineers. John Maynard Keynes (1931) famously opined, “If economists could manage to get themselves thought of as humble, competent people on a level with dentists, that would be splendid.” As we look ahead, “humble” and “competent” remain ideals toward which macroeconomists can aspire.
Interview with Robert A. Mundell
Authors: Vane Howard R , Mulhearn Chris
Published: February 2007

Robert A. Mundell has been Professor of Economics at Columbia University in New York City, New York, since 1974 and University Professor since 2001. In 1999, he was awarded the Nobel Memorial Prize in Economic Science “for his analysis of monetary and fiscal policy under different exchange rate regimes and his analysis of optimum currency areas.” We interviewed Professor Mundell at his hotel in Boston, Massachusetts, on January 7, 2006, while attending the annual meeting of the Allied Social Science Associations.
Trajectories of recovery of quality of life in women after an acute cardiac event
Authors: Worcester Marian Una Christine , Murphy Barbara Mary , Elliott Peter Clifford , Le Grande Michael Richard , Higgins Rosemary Olive , Goble Alan James , Roberts Susan Barbara
Published: February 2007

Objectives. Female cardiac patients' health‐related quality of life (HRQoL) during the first year after an acute cardiac event was compared with age‐weighted Australian population norms. The impact of age, event type and cardiac rehabilitation (CR) programme attendance on recovery was assessed.

Methods. The short form 36‐item health survey (SF‐36) was administered to 229 women aged from 36 to 84 years consecutively admitted to 4 hospitals after acute myocardial infarction (AMI) or to undergo coronary artery bypass graft surgery (CABGS). Data were collected at 4 time points over 12 months. SF‐36 subscale scores were compared with age‐weighted norms for Australian women. Mplus was used to analyse growth trajectories for SF‐36 subscales.

Results. Patients had impaired HRQoL at baseline (except in general health), with progressive improvement over time. Recovery to normative levels was fastest in the areas of bodily pain and mental health (by 2 months) and slowest in the area of physical functioning, and physical and emotional role limitations (by 12 months). By 4 months, general health scores had surpassed population norms. For all scales, most improvement occurred in the first 2 months, with little subsequent improvement. CABGS patients showed significantly more improvement than AMI patients in several areas, partly due to the poorer functioning of CABGS patients at baseline. Rate of improvement was not influenced by patients' age or frequency of CR attendance.

Conclusion. Impairment of HRQoL in female cardiac patients is most pronounced at the time of the event, with most recovery occurring during early convalescence and full recovery in all domains by 12 months post‐event.
Synthetic studies toward shellfish toxins containing spiroacetal units
Authors: Brimble Margaret A. , Halim Rosliana
Published: February 2007

The synthesis of the ABC spiroacetal-containing fragment of the marine biotoxins, the pectenotoxins (PTXs), is described. The synthetic strategy involves appendage of the highly substituted tetrahydofuran C ring to the AB spiroacetal unit via stereocontrolled cyclization of a γ-hydroxyepoxide. The bis-spiroacetal moiety of the spirolide family of shellfish toxins is also described, making use of an iterative radical oxidative cyclization strategy.
Higher Concentrations of Alanine Aminotransferase within the Reference Interval Predict Nonalcoholic Fatty Liver Disease
Authors: Chang Yoosoo , Ryu Seungho , Sung Eunju , Jang Yumi
Published: February 2007

Background: In nonalcoholic fatty liver disease (NAFLD), increased alanine aminotransferase (ALT) concentrations are considered to be a consequence of hepatocyte damage. We performed a prospective study to examine the association between ALT within its reference interval and risk for subsequent development of NAFLD.

Methods: The study cohort comprised 5237 healthy men without diagnosed NAFLD and without increases of either ALT (≥35 U/L) or γ-glutamyltransferase (GGT; ≥40 U/L) above the reference intervals. We assessed alcohol intake via self-reporting (questionnaire) and performed biochemical tests for liver and metabolic function and abdominal ultrasonography. We used the Cox proportional hazards model to calculate the adjusted hazard ratios (aHRs) in the model for NAFLD.

Results: During 13 276.6 person-years of follow-up over a 4-year period, 984 new incident cases of NAFLD developed. We adjusted for age, weight change, body mass index, glucose, blood pressure, triglycerides, HDL cholesterol, smoking, alcohol consumption, regular exercise, homeostasis model assessment of insulin resistance, C-reactive protein, and incident diabetes. Compared with an ALT concentration of <16 U/L, aHR values (95% confidence intervals) for ALT concentrations were 1.53 (1.18–1.98), 1.66 (1.29–2.13), 1.62 (1.26–2.08), and 2.21 (1.73–2.81) for ALT concentrations of 16–18, 19–21, 22–25, and 26–34 U/L, respectively. This relationship remained significant even among normal-weight participants who were still within the reference interval of ALT and GGT at all follow-up examinations.

Conclusions: In apparently healthy, nondiabetic Korean men, increased ALT concentration, even within the reference interval, was an independent predictor of incident NAFLD.
Hellhound on my trail: Crossroads and the Racist Ravishment
Authors: Fitzsimmons Lorna
Published: February 2007

This article analyses the ideological implications of Faustian figurations in Crossroads (1986) in the context of other post-World War Two American films featuring a musical demonic compact and the blackface economy within American culture. The essay demonstrates that the film's
narrative of a white Julliard musician's transgressive desire to play the blues transposes the minstrel form and the longstanding racial bias within Faustian discourses.
El proceso de la recuperacin de la memoria histrica en Espaa: Una aproximacin a los movimientos sociales por la memoria
Authors: Biesca Sergio Glvez
Published: February 2007

This article analyses the socio-political phenomenon of the recovery of historical memory in Spain. The way that the transition to democracy developed included what is now called the Spanish model of impunity, the main consequence of which is that the victims of the Francoist repression
received neither due recognition nor moral, juridical or economic reparations. The article studies the elements that have intervened in this process during the last five years: the normalization of the history of the Spanish Civil War and Francoist repression; the birth and consolidation of
the associative movement for Memory; and the adoption of institutional measures to compensate the victims. Lastly, from a historiographical perspective, the text raises the issue of the increasing political and media manipulation of the Memory phenomenon.
ADrosophilaModel of Mutant Human Parkin-Induced Toxicity Demonstrates Selective Loss of Dopaminergic Neurons and Dependence on Cellular Dopamine
Authors: Sang Tzu-Kang , Chang Hui-Yun , Lawless George M. , Ratnaparkhi Anuradha , Mee Lisa , Ackerson Larry C. , Maidment Nigel T. , Krantz David E. , Jackson George R.
Published: February 2007

Mutations in human parkin have been identified in familial Parkinson's disease and in some sporadic cases. Here, we report that expression of mutant but not wild-type human parkin inDrosophilacauses age-dependent, selective degeneration of dopaminergic (DA) neurons accompanied by a progressive motor impairment. Overexpression or knockdown of theDrosophilavesicular monoamine transporter, which regulates cytosolic DA homeostasis, partially rescues or exacerbates, respectively, the degenerative phenotypes caused by mutant human parkin. These results support a model in which the vulnerability of DA neurons to parkin-induced neurotoxicity results from the interaction of mutant parkin with cytoplasmic dopamine.
Transducin Translocation in Rods Is Triggered by Saturation of the GTPase-Activating Complex
Authors: Lobanova Ekaterina S. , Finkelstein Stella , Song Hongman , Tsang Stephen H. , Chen Ching-Kang , Sokolov Maxim , Skiba Nikolai P. , Arshavsky Vadim Y.
Published: February 2007

Light causes massive translocation of G-protein transducin from the light-sensitive outer segment compartment of the rod photoreceptor cell. Remarkably, significant translocation is observed only when the light intensity exceeds a critical threshold level. We addressed the nature of this threshold using a series of mutant mice and found that the threshold can be shifted to either a lower or higher light intensity, dependent on whether the ability of the GTPase-activating complex to inactivate GTP-bound transducin is decreased or increased. We also demonstrated that the threshold is not dependent on cellular signaling downstream from transducin. Finally, we showed that the extent of transducin α subunit translocation is affected by the hydrophobicity of its acyl modification. This implies that interactions with membranes impose a limitation on transducin translocation. Our data suggest that transducin translocation is triggered when the cell exhausts its capacity to activate transducin GTPase, and a portion of transducin remains active for a sufficient time to dissociate from membranes and to escape from the outer segment. Overall, the threshold marks the switch of the rod from the highly light-sensitive mode of operation required under limited lighting conditions to the less-sensitive energy-saving mode beneficial in bright light, when vision is dominated by cones.
Explaining Change in Quality of Life of Children and Adolescents With Anorectal Malformations or Hirschsprung Disease
Authors: Hartman Esther E. , Oort Frans J. , Aronson Daniel C. , Hanneman Marianne J.G. , van Heurn Ernest , de Langen Zacharias J. , Madern Gerard C. , Rieu Paul N.M.A. , van der Zee David C. , Looyaard Nic , van Silfhout-Bezemer Marina , Sprangers Mirjam A.G.
Published: February 2007

OBJECTIVES. The purpose of this work was to examine changes in quality of life, disease-specific functioning, and psychosocial competencies of children and adolescents (8–16 years of age) with anorectal malformations or Hirschsprung disease and to identify predictors of change in quality of life by testing an explanatory model in which background variables explained changes in quality of life via changes in disease-specific functioning and psychosocial competencies.

METHODS. Questionnaires were administered to 129 patients with anorectal malformations and 121 patients with Hirschsprung disease within a 3-year interval. Clinical and sociodemographic background variables were measured on the first occasion. Quality of life (physical and mental), disease-specific functioning (defecation-related), and psychosocial competencies (self-esteem, athletic competencies, and school attitude) were measured on both occasions.

RESULTS. Patients improved in disease-specific functioning and mental quality of life. Changes in quality of life were indeed explained by the explanatory model. Among other things, the results indicated that patients with a severe form of the disease or with additional congenital diseases showed worsening of school attitude, which in turn affected change in mental quality of life negatively.

CONCLUSIONS. Children and adolescents with anorectal malformations or Hirschsprung disease reported better quality of life over time. To improve and maintain an optimal level of children's and adolescents' quality of life, it is important to direct treatment both to reducing symptoms and enhancing psychosocial competencies, in particular by paying attention to school attitude.
Sleepless in America: Inadequate Sleep and Relationships to Health and Well-being of Our Nation's Children
Authors: Smaldone Arlene , Honig Judy C. , Byrne Mary W.
Published: February 2007

OBJECTIVE. Our goal was to identify characteristics associated with inadequate sleep for a national random sample of elementary school–aged children (6–11 years) and adolescents (12–17 years).

METHODS. Data from 68418 participants in the 2003 National Survey of Children's Health were analyzed by using weighted bivariate and multivariate regression models. The dependent variable was report of not getting enough sleep for a child of his or her age ≥1 night of the past week. Independent variables included demographic characteristics, child health, school and other activities, and family life.

RESULTS. Parents of elementary school–aged children with inadequate sleep were more likely to report that their child was having problems at school or had a father with fair or poor health. Parents of adolescents with inadequate sleep were more likely to report that their child had an atopic condition, frequent or severe headaches, a parent with less-than-excellent emotional health, or experienced frequent parental anger. Inadequate sleep in both age groups was associated with parental report that their child usually or always displayed depressive symptomatology, family disagreements involved heated arguing, or parental concern that the child was not always safe at home, at school, or in their neighborhood.

CONCLUSIONS. Approximately 15 million American children are affected by inadequate sleep. Primary care providers should routinely identify and address inadequate sleep and its associated health, school, and family factors.
Lifetime Prevalence of Learning Disability Among US Children
Authors: Altarac Maja , Saroha Ekta
Published: February 2007

OBJECTIVE. Our goal was to examine the lifetime prevalence of learning disability by sociodemographic and family-functioning characteristics in US children, with particular attention paid to the children with special health care needs.

METHODS. By using data from the National Survey of Children's Health, we calculated lifetime prevalence of learning disability using a question that asked whether a doctor or other health care or school professional ever told the survey respondent that the child had a learning disability. Children with and those without special health care needs were classified on the basis of how many of 5 definitional criteria for children with special health care needs they met (0–5). Bivariate and multivariate statistical methods were used to assess independent associations of selected sociodemographic and family variables with learning disability.

RESULTS. The lifetime prevalence of learning disability in US children is 9.7%. Although prevalence of learning disability is lower among average developing children (5.4%), it still affected 2.7 million children compared with 3.3 million (27.8%) children with special health care needs. As the number of definitional criteria children with special health care needs met increased from 1 to 5, so did the prevalence of learning disability (15.0%, 27.1%, 41.6%, 69.3%, and 87.8%, respectively). In the adjusted logistic regression model, in addition to the number of definitional criteria the children met, variables associated with the increased odd ratios of learning disability were lower education, all categories of poverty <300% of the federal poverty level, being male, increasing age, having a 2-parent stepfamily or other family structure, being adopted, presence of a smoker, respondent's higher responses on aggravation in parenting scale, sharing ideas with the child less than very well, and never, rarely, or sometimes discussing serious disagreements calmly.

CONCLUSIONS. Although more than half of lifetime prevalence of learning disability occurred in children with special health care needs, it is a significant morbidity in average-developing children as well. Learning disabilities represent important comorbidities among children with special health care needs.
Percutaneous Device Closure of Atrial Septal Defect in a Premature Infant With Rapid Improvement in Pulmonary Status
Authors: Lim D. Scott , Matherne G. Paul
Published: February 2007

Atrial septal defects are a common congenital heart defect and may complicate the course of a premature infant by imposing volume overload to the lungs. Surgical closure requires cardiopulmonary bypass and, frequently, a midline sternotomy. Recently, percutaneous transcatheter devices were approved for atrial septal defect closure but have been limited to use in larger children. Here we present the first known report of a transcatheter device closure of an atrial septal defect in a premature infant, which resulted in rapid improvement of the patient's respiratory status.
Microstructure and mechanical properties of slowly cooled Cu47.5Zr47.5Al5
Authors: Das J. , Pauly S. , Duhamel C. , Wei B.C. , Eckert J.
Published: February 2007

Cu47.5Zr47.5Al5 was prepared by arc melting and solidified in situ by suction casting into 2–5-mm-diameter rods under various cooling rates (200–2000 K/s). The microstructure was investigated along the length of the rods by electron microscopy, differential scanning calorimetry and mechanical properties were investigated under compression. The microstructure of differently prepared specimens consists of macroscopic spherical shape chemically inhomogeneous regions together with a low volume fraction of randomly distributed CuZr B2 phase embedded in a 2–7 nm size clustered “glassy-martensite” matrix. The as-cast specimens show high yield strength (1721 MPa), pronounced work-hardening behavior up to 2116 MPa and large fracture strain up to 12.1–15.1%. The fracture strain decreases with increasing casting diameter. The presence of chemical inhomogenities and nanoscale “glassy-martensite” features are beneficial for improving the inherent ductility of the metallic glass.
Mechanical properties of iron-based bulk metallic glasses
Authors: Gu X.J. , Poon S. Joseph , Shiflet Gary J.
Published: February 2007

Iron-based bulk metallic glasses (BMGs) are characterized by high fracture strengths and elastic moduli, with some exhibiting fracture strengths near 4 GPa, 2–3 times those of conventional high-strength steels. Among the Fe-based BMGs, the non-ferromagnetic ones, designated “non-ferromagnetic amorphous steel alloys” by two of the present authors [S.J. Poon et al.: Appl. Phys. Lett.83, 1131 (2003)], have glass-forming ability high enough to form single-phase glassy rods with diameters reaching 16 mm. Fe-based BMGs designed for structural applications must exhibit some plasticity under compression. However, the role of alloy composition on plastic and brittle failures in metallic glasses is largely unknown. In view of a recently observed correlation that exists between plasticity and Poisson’s ratio for BMGs, compositional effects on plasticity and elastic properties in amorphous steels were investigated. For the new amorphous steels, fracture strengths as high as 4.4 GPa and plastic strains reaching ∼0.8% were measured. Plastic failure instead of brittle failure was observed as the Poisson’s ratio approached 0.32 from below. Investigation of the relationship between the elastic moduli of the alloys and those of the alloying elements revealed that interatomic interactions in addition to the elastic moduli of the alloying elements must be considered in designing ductile Fe-based BMGs. The prospects for attaining high fracture toughness in Fe-based BMGs are discussed in this article.
Strain rate dependence of plastic flow in Ce-based bulk metallic glass during nanoindentation
Authors: Wei B.C. , Zhang L.C. , Zhang T.H. , Xing D.M. , Das J. , Eckert J.
Published: February 2007

The strain rate dependence of plastic deformation of Ce60Al15Cu10Ni15 bulk metallic glass was studied by nanoindentation. Even though the ratio of room temperature to the glass transition temperature was very high (0.72) for this alloy, the plastic deformation was dominated by shear banding under nanoindentation. The alloy exhibited a critical loading rate dependent serrated flow feature. That is, with increasing loading rate, the alloy exhibited a transition from less prominent serrated flow to pronounced serrated flow during continuous loading but from serrated to smoother flow during stepped loading.
Compressive properties of bulk metallic glass with small aspect ratio
Authors: Wu F.F. , Zhang Z.F. , Mao S.X.
Published: February 2007

The quasi-static compressive deformation behavior of a Vitreloy 1 bulk metallic glass (BMG) with an aspect ratio of 0.25 was investigated. It is found that the friction and the confinement at the specimen–loading platen interface will cause the dramatic increase in the compressive load, leading to higher compressive strength. In particular, the BMG specimens show great plastic-deformation ability, and plenty of interacted, deflected, wavy, or branched shear bands were observed on the surfaces after plastic deformation. The formation of the strongly interacted, deflected, wavy, or branched shear bands can be attributed to the triaxial stress state in the glassy specimens with a very small aspect ratio.
Students' Stories: Adolescents Constructing Multiple Literacies Through Nature Journaling
Authors: McMillan Sally , Wilhelm Jennifer
Published: February 2007

The integration of nature studies within language arts instruction offers multiple possibilities for guiding students toward close readings of literature, their changing selves, natural phenomena, and the world around them. The authors document their own rediscovery of nature study and what happened when environmental observations were incorporated into the lives of 67 seventh‐grade students as an alternative mode of literacy instruction.
Story Characters, Problems, and Settings Are Elemental
Authors: Kurkjian Catherine , Livingston Nancy
Published: February 2007

The authors review numerous books with memorable characters, settings, and situations that create engaging plots.
Gator's Adventures: A Lesson in Literacy and Community
Authors: Hall Katrina
Published: February 2007

This article describes a take‐home literacy project in which kindergartners took home books, a stuffed animal, a camera, and a shared writing activity to complete with their families. The children later shared their writing and experiences in school. The resulting written responses and photographs depicted a level of involvement with the families that was not expected.

At the end of the year, the writings and photographs were collected and each child was given a book that included all of children's writings and photographs. These books became treasured keepsakes of their year in kindergarten and a wonderful artifact not only of reading and writing for relevant purposes but also of a meaningful home activity that became a community‐building project as well.
Evaluation of Two Different Resonance Frequency Devices to Detect Implant Stability: A Clinical Trial
Authors: Valderrama Pilar , Oates Thomas W. , Jones Archie A. , Simpson James , Schoolfield John D. , Cochran David L.
Published: February 2007

Background: Resonance frequency analysis (RFA) provides a non‐invasive assessment of implant stability. The established RFA device uses electronic technology, whereas a recently developed device uses magnetic technology. The goal of this clinical trial was to evaluate the ability of the magnetic RFA device to detect changes in stability during early healing following implant placement and to determine whether the implant stability quatient (ISQ) values obtained correlated with those made with the electronic device.

Methods: RFA assessments were performed using electronic‐ and magnetic‐based devices on 34 non‐submerged titanium dental implants in 17 patients. Each patient received two implants in the posterior maxilla or mandible. Implant stability was measured at placement and weekly until week 6, when implants received provisional crowns, and at 12 weeks, when definitive crowns were cemented. During each visit, measurements were taken three times and averaged to obtain a single representative ISQ for each device.

Results: At placement, the mean ISQ obtained with the electronic device was 61.9 (95% confidence interval [CI], 59.4 to 64.3); it increased to 63.2 (95% CI, 61.2 to 65.2) at 12 weeks. With the magnetic device, the mean ISQs were 70.6 (95% CI, 68.4 to 72.8) and 75.9 (95% CI, 74.2 to 77.7), respectively. Both devices indicated a pattern of decreased mean stability from 1 to 3 weeks post‐placement, small fluctuations in mean ISQ from 3 to 6 weeks, and significantly increased mean stability from 6 to 12 weeks. For the complete set of implant measures across all weeks, the paired electronic and magnetic ISQ values correlated significantly (r = 0.52; P <0.001).

Conclusions: This study demonstrates that changes in implant stability measured with the newer magnetic device correlate well with those found with the electronic device. Both devices confirmed the initial decreases in implant stability that occur following placement and identified an increase in stability during the first 6 weeks of functional loading.
Randomized, Controlled Histologic and Histomorphometric Evaluation of Implants With Nanometer‐Scale Calcium Phosphate Added to the Dual Acid‐Etched Surface in the Human Posterior Maxilla
Authors: Orsini Giovanna , Piattelli Maurizio , Scarano Antonio , Petrone Giovanna , Kenealy James , Piattelli Adriano , Caputi Sergio
Published: February 2007

Background: Placement of dental implants in the posterior maxilla has been associated with higher rates of failure that are due, in part, to the poor bone quality of this region. The purpose of the present study was the histologic and histomorphometric evaluation of the bone around a new implant surface treatment created by a deposition of nanometer‐sized calcium phosphate particles added to the dual acid‐etched surface.

Methods: One custom‐made 2 × 10‐mm site evaluation implant (SEI) with this novel treatment surface (test) and one SEI with the dual acid‐etched surface without treatment (control) were placed in the posterior maxilla of 15 patients. All SEIs were retrieved after 2 months and evaluated under confocal laser scanning microscopy (CLSM) and by light microscopy for histomorphometric analysis of the bone–implant contact (BIC).

Results: Histologic observations in control SEIs showed formation of new bone around the implant surface; however, it was not always in direct contact with the entire perimeter of the threads. The mean BIC was 19% ± 14.2%. Test SEIs showed peri‐implant bone tightly contacting the implant surface and better adapted to the threads. Three‐dimensional reconstruction of sections obtained using CLSM showed the intimacy of the contact between bone and test SEI surface through the entire thickness of the specimens. The mean BIC was 32.2% ± 18.5%.

Conclusions: After 2 months of healing, comparison of the BIC values showed a statistically significant greater mean BIC for test SEIs than for controls. The clinical implications of these results included shortening of the implant healing period and earlier loading protocols.
The Role of Perceived Personal Barriers to Engagement in Leisure-Time Physical Activity
Authors: Reichert Felipe F. , Barros Aluísio J.D. , Domingues Marlos R. , Hallal Pedro C.
Published: February 2007

Objectives. We sought to identify perceived personal barriers to physical activity and examine the potential association between these barriers and sociodemographic and behavioral variables, including participation in leisure-time physical activity.

Methods. In 2003, we conducted a population-based study in Pelotas, Brazil. Participants aged 20 years and older were selected according to a multistage sampling strategy. Participants responded to both the International Physical Activity Questionnaire and a standardized questionnaire investigating 8 perceived personal barriers.

Results. Only 26.8% of participants achieved 150 minutes per week of leisure-time physical activity. Lack of money (40.3%) and feeling too tired (38.1%) were the most frequently reported barriers to physical activity. A dose–response group association was observed between number of perceived barriers and level of physical activity. In the multivariable analysis, lack of time, dislike of exercising, feeling too tired, lack of company, and lack of money were associated with physical inactivity.

Conclusion. Detection of the determinants of physical inactivity, a growing epidemic, should be a public health priority. Brazil is a middle-income (developing) country. The prevalence of most of the personal barriers studied was higher in this population than those levels observed in high-income (developed) countries. Perceiving 5 of the 8 barriers investigated was inversely associated with leisure-time physical activity level.
Bringing Safe Water to Remote Populations: An Evaluation of a Portable Point-of-Use Intervention in Rural Madagascar
Authors: Ram Pavani Kalluri , Kelsey Elaine , Rasoatiana  , Miarintsoa Rabeantoandro Rado , Rakotomalala Oliver , Dunston Chris , Quick Robert E.
Published: February 2007

Rural populations disproportionately lack access to improved water supplies. We evaluated a novel scheme that employed community-based sales agents to disseminate the Safe Water System (SWS)—a household-level water chlorination and safe storage intervention—in rural Madagascar.

Respondents from 242 households in 4 villages were interviewed; all used surface water for drinking water. Respondents from 239 households (99%) had heard of Sûr’Eau, the SWS disinfectant; 226 (95%) reported having ever used Sûr’Eau, and 166 (73%) reported current use. Current Sûr’Eau use was confirmed in 54% of households. Community sales agents effectively motivated their neighbors to adopt a new health behavior that prevents diarrhea.

Future work should focus on strategies for sustaining SWS use, factors that motivate community-based sales agents to promote SWS, and the feasibility of scaling up this approach.