bluuebunny/crossref_metadata_2025 huggingface dataset:
Diminished rostral anterior cingulate cortex activation during trauma-unrelated emotional interference in PTSD
Authors: Offringa Reid , Handwerger Brohawn Kathryn , Staples Lindsay K , Dubois Stacey J , Hughes Katherine C , Pfaff Danielle L , VanElzakker Michael B , Davis F Caroline , Shin Lisa M
Published: May 2013

Background

Previous research suggests that individuals with posttraumatic stress disorder (PTSD) preferentially attend to trauma-related emotional stimuli and have difficulty completing unrelated concurrent tasks. Compared to trauma-exposed control groups, individuals with PTSD also exhibit lower rostral anterior cingulate cortex (rACC) activation during tasks involving interference from trauma-related stimuli. However, it is not clear whether relatively diminished rACC activation in PTSD also occurs during interference tasks involving trauma-unrelated emotional stimuli. The present study employed functional magnetic resonance imaging (fMRI) and an interference task that involves emotional facial expressions and elicits rACC activation in healthy participants.

Findings

While performing a trauma-unrelated emotional interference task, participants with PTSD (n=17) showed less rACC activation than trauma-exposed non-PTSD (TENP; n=18) participants. In the PTSD group, rACC activation was negatively correlated with the severity of re-experiencing symptoms. The two groups did not significantly differ on behavioral measures (i.e., response times and error rates).

Conclusions

These findings suggest that relatively diminished rACC activation in PTSD can be observed in interference tasks involving trauma-unrelated emotional stimuli, indicating a more general functional brain abnormality in this disorder. Future neuroimaging studies need not employ trauma-related stimuli in order to detect rACC abnormalities in PTSD.
Forward modeling of gravity data using finite-volume and finite-element methods on unstructured grids
Authors: Jahandari Hormoz , Farquharson Colin G.
Published: May 2013

Minimum-structure inversion is one of the most effective tools for the inversion of gravity data. However, the standard Gauss-Newton algorithms that are commonly used for the minimization procedure and that employ forward solvers based on analytic formulas require large memory storage for the formation and inversion of the involved matrices. An alternative to the analytical solvers are numerical ones that result in sparse matrices. This sparsity suits gradient-based minimization methods that avoid the explicit formation of the inversion matrices and that solve the system of equations using memory-efficient iterative techniques. We have developed several numerical schemes for the forward modeling of gravity data using the finite-element and finite-volume methods on unstructured grids. In the finite-volume method, a Delaunay tetrahedral grid and its dual Voronoï grid are used to find the primary solution (i.e., gravitational potential) at the centers and vertices of the tetrahedra, respectively (cell-centered and vertex-centered schemes). In the finite-element method, Delaunay tetrahedral grids are used to develop linear and quadratic finite-element schemes. Different techniques are used to recover the vertical component of gravitational acceleration from the gravitational potential. In the finite-volume scheme, a differencing method is used; in the finite-element method, basis functions are used. The capabilities of the finite-volume and finite-element schemes were tested on simple and realistic synthetic examples. The results showed that the quadratic finite-element scheme is the most accurate but also the most computationally demanding scheme. The best trade-offs between accuracy and computational resource requirement were achieved by the linear finite-element and vertex-centered finite-volume schemes.
Detection of Circulating Tumor Cells Harboring a Unique ALK Rearrangement in ALK-Positive Non–Small-Cell Lung Cancer
Authors: Pailler Emma , Adam Julien , Barthélémy Amélie , Oulhen Marianne , Auger Nathalie , Valent Alexander , Borget Isabelle , Planchard David , Taylor Melissa , André Fabrice , Soria Jean Charles , Vielh Philippe , Besse Benjamin , Farace Françoise
Published: May 2013

Purpose

The diagnostic test for ALK rearrangement in non–small-cell lung cancer (NSCLC) for crizotinib treatment is currently done on tumor biopsies or fine-needle aspirations. We evaluated whether ALK rearrangement diagnosis could be performed by using circulating tumor cells (CTCs).

Patients and Methods

The presence of an ALK rearrangement was examined in CTCs of 18 ALK-positive and 14 ALK-negative patients by using a filtration enrichment technique and filter-adapted fluorescent in situ hybridization (FA-FISH), a FISH method optimized for filters. ALK-rearrangement patterns were determined in CTCs and compared with those present in tumor biopsies. ALK-rearranged CTCs and tumor specimens were characterized for epithelial (cytokeratins, E-cadherin) and mesenchymal (vimentin, N-cadherin) marker expression. ALK-rearranged CTCs were monitored in five patients treated with crizotinib.

Results

All ALK-positive patients had four or more ALK-rearranged CTCs per 1 mL of blood (median, nine CTCs per 1 mL; range, four to 34 CTCs per 1 mL). No or only one ALK-rearranged CTC (median, one per 1 mL; range, zero to one per 1 mL) was detected in ALK-negative patients. ALK-rearranged CTCs harbored a unique (3′5′) split pattern, and heterogeneous patterns (3′5′, only 3′) of splits were present in tumors. ALK-rearranged CTCs expressed a mesenchymal phenotype contrasting with heterogeneous epithelial and mesenchymal marker expressions in tumors. Variations in ALK-rearranged CTC levels were detected in patients being treated with crizotinib.

Conclusion

ALK rearrangement can be detected in CTCs of patients with ALK-positive NSCLC by using a filtration technique and FA-FISH, enabling both diagnostic testing and monitoring of crizotinib treatment. Our results suggest that CTCs harboring a unique ALK rearrangement and mesenchymal phenotype may arise from clonal selection of tumor cells that have acquired the potential to drive metastatic progression of ALK-positive NSCLC.
Normalizing Tumor Microenvironment to Treat Cancer: Bench to Bedside to Biomarkers
Authors: Jain Rakesh K.
Published: May 2013

For almost four decades, my work has focused on one challenge: improving the delivery and efficacy of anticancer therapeutics. Working on the hypothesis that the abnormal tumor microenvironment—characterized by hypoxia and high interstitial fluid pressure—fuels tumor progression and treatment resistance, we developed an array of sophisticated imaging technologies and animal models as well as mathematic models to unravel the complex biology of tumors. Using these tools, we demonstrated that the blood and lymphatic vasculature, fibroblasts, immune cells, and extracellular matrix associated with tumors are abnormal, which together create a hostile tumor microenvironment. We next hypothesized that agents that induce normalization of the microenvironment can improve treatment outcome. Indeed, we demonstrated that judicious use of antiangiogenic agents—originally designed to starve tumors—could transiently normalize tumor vasculature, alleviate hypoxia, increase delivery of drugs and antitumor immune cells, and improve the outcome of various therapies. Our trials of antiangiogenics in patients with newly diagnosed and recurrent glioblastoma supported this concept. They revealed that patients whose tumor blood perfusion increased in response to cediranib survived 6 to 9 months longer than those whose blood perfusion did not increase. The normalization hypothesis also opened doors to treating various nonmalignant diseases characterized by abnormal vasculature, such as neurofibromatosis type 2. More recently, we discovered that antifibrosis drugs capable of normalizing the tumor microenvironment can improve the delivery and efficacy of nano- and molecular medicines. Our current efforts are directed at identifying predictive biomarkers and more-effective strategies to normalize the tumor microenvironment for enhancing anticancer therapies.
Insulin and IGF-I Inhibit GH Synthesis and Release in Vitro and in Vivo by Separate Mechanisms
Authors: Gahete Manuel D. , Córdoba-Chacón José , Lin Qing , Brüning Jens C. , Kahn C. Ronald , Castaño Justo P. , Christian Helen , Luque Raúl M. , Kineman Rhonda D.
Published: May 2013

IGF-I is considered a primary inhibitor of GH secretion. Insulin may also play an important role in regulating GH levels because insulin, like IGF-I, can suppress GH synthesis and release in primary pituitary cell cultures and insulin is negatively correlated with GH levels in vivo. However, understanding the relative contribution insulin and IGF-I exert on controlling GH secretion has been hampered by the fact that circulating insulin and IGF-I are regulated in parallel and insulin (INSR) and IGF-I (IGFIR) receptors are structurally/functionally related and ubiquitously expressed. To evaluate the separate roles of insulin and IGF-I in directly regulating GH secretion, we used the Cre/loxP system to knock down the INSR and IGFIR in primary mouse pituitary cell cultures and found insulin-mediated suppression of GH is independent of the IGFIR. In addition, pharmacological blockade of intracellular signals in both mouse and baboon cultures revealed insulin requires different pathways from IGF-I to exert a maximal inhibitory effect on GH expression/release. In vivo, somatotrope-specific knockout of INSR (SIRKO) or IGFIR (SIGFRKO) increased GH levels. However, comparison of the pattern of GH release, GH expression, somatotrope morphometry, and pituitary explant sensitivity to acute GHRH challenge in lean SIRKO and SIGFRKO mice strongly suggests the primary role of insulin in vivo is to suppress GH release, whereas IGF-I serves to regulate GH synthesis. Finally, SIRKO and/or SIGFRKO could not prevent high-fat, diet-induced suppression of pituitary GH expression, indicating other factors/tissues are involved in the decline of GH observed with weight gain.
Behind the Scenes of the Patient Protection and Affordable Care Act: The Making of a Health Care Co-Op
Authors: Giaimo Susan
Published: May 2013

A primary goal of the Patient Protection and Affordable Care Act (PPACA) is to reduce the number of uninsured by making health insurance more affordable for small businesses and individuals. Toward that end, the PPACA encourages the creation of nonprofit, member-owned health insurance cooperatives to operate inside each state exchange. Co-ops face significant challenges in entering mature insurance markets, but they also possess unique characteristics that may help them survive and thrive. Using Common Ground Healthcare Cooperative in Wisconsin as a case study, this article traces the origins of co-ops in health care reform at national and state levels and analyzes the political and technical challenges and opportunities facing these organizations.
SRF selectively controls tip cell invasive behavior in angiogenesis
Authors: Franco Claudio A. , Blanc Jocelyne , Parlakian Ara , Blanco Raquel , Aspalter Irene M. , Kazakova Natalia , Diguet Nicolas , Mylonas Elena , Gao-Li Jacqueline , Vaahtokari Anne , Penard-Lacronique Virgine , Fruttiger Markus , Rosewell Ian , Mericskay Mathias , Gerhardt Holger , Li Zhenlin
Published: May 2013

Efficient angiogenic sprouting is essential for embryonic, postnatal and tumor development. Serum response factor (SRF) is known to be important for embryonic vascular development. Here, we studied the effect of inducible endothelial-specific deletion of Srf in postnatal and adult mice. We find that endothelial SRF activity is vital for postnatal growth and survival, and is equally required for developmental and pathological angiogenesis, including during tumor growth. Our results demonstrate that SRF is selectively required for endothelial filopodia formation and cell contractility during sprouting angiogenesis, but seems dispensable for vascular remodeling. At the molecular level, we observe that vascular endothelial growth factor A induces nuclear accumulation of myocardin-related transcription factors (MRTFs) and regulates MRTF/SRF-dependent target genes including Myl9, which is important for endothelial cell migration in vitro. We conclude that SRF has a unique function in regulating migratory tip cell behavior during sprouting angiogenesis. We hypothesize that targeting the SRF pathway could provide an opportunity to selectively target tip cell filopodia-driven angiogenesis to restrict tumor growth.
Tbx2/3 is an essential mediator within the Brachyury gene network during Ciona notochord development
Authors: José-Edwards Diana S. , Oda-Ishii Izumi , Nibu Yutaka , Di Gregorio Anna
Published: May 2013

T-box genes are potent regulators of mesoderm development in many metazoans. In chordate embryos, the T-box transcription factor Brachyury (Bra) is required for specification and differentiation of the notochord. In some chordates, including the ascidian Ciona, members of the Tbx2 subfamily of T-box genes are also expressed in this tissue; however, their regulatory relationships with Bra and their contributions to the development of the notochord remain uncharacterized. We determined that the notochord expression of Ciona Tbx2/3 (Ci-Tbx2/3) requires Ci-Bra, and identified a Ci-Tbx2/3 notochord CRM that necessitates multiple Ci-Bra binding sites for its activity. Expression of mutant forms of Ci-Tbx2/3 in the developing notochord revealed a role for this transcription factor primarily in convergent extension. Through microarray screens, we uncovered numerous Ci-Tbx2/3 targets, some of which overlap with known Ci-Bra-downstream notochord genes. Among the Ci-Tbx2/3 notochord targets are evolutionarily conserved genes, including caspases, lineage-specific genes, such as Noto4, and newly identified genes, such as MLKL. This work sheds light on a large section of the notochord regulatory circuitry controlled by T-box factors, and reveals new components of the complement of genes required for the proper formation of this structure.
Theoretical Model for the Carboxylic Group Acidity Constant Based on Connectivity Index 3χv
Authors: Milicevic Ante , Raos Nenad
Published: May 2013

We developed a regression model for prediction of COOH acidity constant on 19 amino and 16 aliphatic monocarboxylic acids. As variables we employed two subsummations of 3χv index terms, 3χv(chain) and 3χv(side). The calculation of 3χv(chain) includes only atoms constituting the main chain in a molecule, whereas the calculation of 3χv(side) includes atoms from the side chains. The model yielded r = 0.998, S.E. = 0.053 and r = 0.974, S.E. = 0.017, for amino and aliphatic monocarboxylic acids, respectively. As a test set we used three amino acids, valine, leucine, and isoleucine, predicting their pKa values with root-mean-square error, rms = 0.07 (I = 0) and 0.10 (I = 0.1 mol kg−1).
Formation of Au Nanostructure by Electrodeposition in a Mesoporous Silica Film with Interconnected Cage-Type Mesopores
Authors: Kanno Yosuke , Kuroda Kazuyuki
Published: May 2013

A mesoporous silica film with interconnected cage-type mesopores is found to work as a scaffold to construct a novel nanostructured Au by electrodeposition. The nanostructure consists of Au nanoparticles located in the mesopores and they are connected to each other, which induces a red shift in the visible absorption band.
Ab Initio QM/MM-MC Study on Hydrogen Transfer of Glycine Tautomerization in Aqueous Solution: Helmholtz Energy Changes along Water-mediated and Direct Processes
Authors: Miyamoto Hidenori , Aida Misako
Published: May 2013

Helmholtz free-energy changes in aqueous solution along two paths of glycine tautomerization were investigated by using an ab initio QM/MM-MC method with the thermodynamic perturbation theory. Glycine and one water molecule were treated at the quantum mechanics (QM) level of MP2/6-31G(d); these were surrounded by 100 water molecules at the molecular mechanics (MM) level of TIP3P. AIM (atoms-in-molecules) analysis showed that the transfer of two hydrogen atoms occurs simultaneously along the water-mediated path. The free-energy barrier height of this path in aqueous solution was higher than that of the direct path.
Dehydrative Esterification of Acetic Acid by Ethanol as a Model Reaction for Polyester Synthesis Catalyzed by Scandium Perfluoroalkanesulfonates and Bis(perfluoroalkanesulfonyl)imides
Authors: Nomura Naoki , Takasu Akinori
Published: May 2013

Scandium perfluoroalkanesulfonates and perfluoroalkanesulfonimides act as catalysts for the polyesterification of dicarboxylic acids by diols. We performed the model esterification between ethanol and acetic acid to measure the extent of the conversions and equilibrium constants for each scandium catalyst. According to the Arrhenius and Eyring constants, the activity of each scandium catalyst depends on its fluorine content and type of ligand, as reflected in the activation entropy values.
Clinical and functional impact of TARBP2 over-expression in adrenocortical carcinoma
Authors: Caramuta Stefano , Lee Linkiat , Özata Deniz M , Akçakaya Pinar , Xie Hong , Höög Anders , Zedenius Jan , Bäckdahl Martin , Larsson Catharina , Lui Weng-Onn
Published: May 2013

Deregulation of microRNA (miRNA) expression in adrenocortical carcinomas (ACCs) has been documented to have diagnostic, prognostic, as well as functional implications. Here, we evaluated the mRNA expression ofDROSHA,DGCR8,DICER(DICER1),TARBP2, andPRKRA, the core components in the miRNA biogenesis pathway, in a cohort of 73 adrenocortical tumors (including 43 adenomas and 30 carcinomas) and nine normal adrenal cortices using a RT-qPCR approach. Our results show a significant over-expression ofTARBP2,DICER, andDROSHAin the carcinomas compared with adenomas or adrenal cortices (P<0.001 for all comparisons). Using western blot and immunohistochemistry analyses, we confirmed the higher expression of TARBP2, DICER, and DROSHA at the protein level in carcinoma cases. Furthermore, we demonstrate that mRNA expression ofTARBP2, but notDICERorDROSHA, is a strong molecular predictor to discriminate between adenomas and carcinomas. Functionally, we showed that inhibition of TARBP2 expression in human NCI-H295R ACC cells resulted in a decreased cell proliferation and induction of apoptosis. TARBP2 over-expression was not related to gene mutations; however, copy number gain of theTARBP2gene was observed in 57% of the carcinomas analyzed. In addition, we identified thatmiR-195andmiR-497could directly regulate TARBP2 and DICER expression in ACC cells. This is the first study to demonstrate the deregulation of miRNA-processing factors in adrenocortical tumors and to show the clinical and biological impact of TARBP2 over-expression in this tumor type.
Genetic Bypass of Aspergillus nidulans crzA Function in Calcium Homeostasis
Authors: Almeida Ricardo S , Loss Omar , Colabardini Ana Cristina , Brown Neil Andrew , Bignell Elaine , Savoldi Marcela , Pantano Sergio , Goldman Maria Helena S , Arst Herbert N , Goldman Gustavo H
Published: May 2013

After dephosphorylation by the phosphatase calcineurin, the fungal transcription factor CrzA enters the nucleus and activates the transcription of genes responsible for calcium homeostasis and many other calcium-regulated activities. A lack of CrzA confers calcium-sensitivity to the filamentous fungus Aspergillus nidulans. To further understand calcium signaling in filamentous fungi and to identify genes that interact genetically with CrzA, we selected for mutations that were able to suppress crzAΔ calcium intolerance and identified three genes. Through genetic mapping, gene sequencing, and mutant rescue, we were able to identify these as cnaB (encoding the calcineurin regulatory subunit), folA (encoding an enzyme involved in folic acid biosynthesis, dihydroneopterin aldolase), and scrC (suppression of crzA-, encoding a hypothetical protein). By using a calcium indicator, Fluo-3, we were able to determine that the wild-type and the suppressor strains were either able to regulate intracellular calcium levels or were able to take up and or store calcium correctly. The increased expression of calcium transporters, pmcA and/or pmcB, in suppressor mutants possibly enabled tolerance to high levels of calcium. Our results suggest that a cnaB suppressor mutation confers calcium tolerance to crzAΔ strains through restoration of calcium homeostasis. These results stress that in A. nidulans there are calcineurin-dependent and CrzA-independent pathways. In addition, it is possible that CrzA is able to contribute to the modulation of folic acid biosynthesis.
Molecular Population Genetics of Inversion Breakpoint Regions inDrosophila pseudoobscura
Authors: Wallace Andre G , Detweiler Don , Schaeffer Stephen W
Published: May 2013

Paracentric inversions in populations can have a profound effect on the pattern and organization of nucleotide variability along a chromosome. Regions near inversion breakpoints are expected to have greater levels of differentiation because of reduced genetic exchange between different gene arrangements whereas central regions in the inverted segments are predicted to have lower levels of nucleotide differentiation due to greater levels of genetic flux among different karyotypes. We used the inversion polymorphism on the third chromosome of Drosophila pseudoobscura to test these predictions with an analysis of nucleotide diversity of 18 genetic markers near and away from inversion breakpoints. We tested hypotheses about how the presence of different chromosomal arrangements affects the pattern and organization of nucleotide variation. Overall, markers in the distal segment of the chromosome had greater levels of nucleotide heterozygosity than markers within the proximal segment of the chromosome. In addition, our results rejected the hypothesis that the breakpoints of derived inversions will have lower levels of nucleotide variability than breakpoints of ancestral inversions, even when strains with gene conversion events were removed. High levels of linkage disequilibrium were observed within all 11 breakpoint regions as well as between the ends of most proximal and distal breakpoints. The central region of the chromosome had the greatest levels of linkage disequilibrium compared with the proximal and distal regions because this is the region that experiences the highest level of recombination suppression. These data do not fully support the idea that genetic exchange is the sole force that influences genetic variation on inverted chromosomes.
Generalized Admixture Mapping for Complex Traits
Authors: Zhu Bin , Ashley-Koch Allison E , Dunson David B
Published: May 2013

Admixture mapping is a popular tool to identify regions of the genome associated with traits in a recently admixed population. Existing methods have been developed primarily for identification of a single locus influencing a dichotomous trait within a case-control study design. We propose a generalized admixture mapping (GLEAM) approach, a flexible and powerful regression method for both quantitative and qualitative traits, which is able to test for association between the trait and local ancestries in multiple loci simultaneously and adjust for covariates. The new method is based on the generalized linear model and uses a quadratic normal moment prior to incorporate admixture prior information. Through simulation, we demonstrate that GLEAM achieves lower type I error rate and higher power than ANCESTRYMAP both for qualitative traits and more significantly for quantitative traits. We applied GLEAM to genome-wide SNP data from the Illumina African American panel derived from a cohort of black women participating in the Healthy Pregnancy, Healthy Baby study and identified a locus on chromosome 2 associated with the averaged maternal mean arterial pressure during 24 to 28 weeks of pregnancy.
Lyme Chondritis Presenting as Painless Ear Erythema
Authors: Srinivasalu Hemalatha , Brescia AnneMarie C. , Rose Carlos D.
Published: May 2013

Erythema of the ear lobe in the context of Lyme disease is caused by either borrelial lymphocytoma or localized erythema migrans. Here we present a case of chondritis limited to the ear cartilage caused by Lyme disease. The patient was treated with ceftriaxone with complete resolution of symptoms.
Texting While Driving and Other Risky Motor Vehicle Behaviors Among US High School Students
Authors: Olsen Emily O’Malley , Shults Ruth A. , Eaton Danice K.
Published: May 2013

OBJECTIVE:

To assess the prevalence of texting/e-mailing while driving (TWD) and association of TWD with other risky motor vehicle (MV) behaviors among US high school students.

METHODS:

Data were used from the Centers for Disease Control and Prevention’s 2011 national Youth Risk Behavior Survey, which assessed TWD during the 30 days before the survey among 8505 students aged ≥16 years from a nationally representative sample of US high school students. TWD frequency was coded into dichotomous and polychotomous variables. Logistic regression assessed the relationship between TWD and other risky driving behaviors, controlling for age, race/ethnicity, and sex.

RESULTS:

The prevalence of TWD on ≥1 days during the 30 days before the survey was 44.5% (95% confidence interval: 40.8%–48.2%). Students who engaged in TWD were more likely than their non-TWD counterparts to not always wear their seatbelt (prevalence ratio; 95% confidence interval: 1.16; 1.07–1.26), ride with a driver who had been drinking alcohol (1.74; 1.57–1.93), and drink alcohol and drive (5.33; 4.32–6.59). These other risky MV behaviors were most likely to occur among students who frequently engaged in TWD.

CONCLUSIONS:

Nearly half of US high school students aged ≥16 years report TWD during the past 30 days; these students are more likely to engage in additional risky MV behaviors. This suggests there is a subgroup of students who may place themselves, their passengers, and others on the road at elevated risk for a crash-related injury or fatality by engaging in multiple risky MV behaviors.
Short-Term Gestation, Long-Term Risk: Prematurity and Chronic Kidney Disease
Authors: Carmody J. Bryan , Charlton Jennifer R.
Published: May 2013

Thanks to remarkable advances in neonatal intensive care, infants who once had little chance for survival can now enter adulthood. Yet the consequences of premature birth or low birth weight (LBW) on nephrogenesis, final nephron number, and long-term kidney function are unclear. This review focuses on the theory, experimental evidence, and observational data that suggest an increased risk of chronic kidney disease (CKD) for infants born prematurely. Many premature and LBW infants begin life with an incomplete complement of immature nephrons. They are then exposed to a variety of external stressors that can hinder ongoing kidney development or cause additional nephron loss such as hemodynamic alterations, nephrotoxic medications, infections, and suboptimal nutrition. Acute kidney injury, in particular, may be a significant risk factor for the development of CKD. According to Brenner’s hypothesis, patients with decreased nephron number develop hyperfiltration that results in sodium retention, hypertension, nephron loss, and CKD due to secondary focal segmental glomerulosclerosis. Because the risk of CKD in premature and LBW infants has not been accurately determined, there are no evidence-based recommendations for screening or management. Yet with the first generation of infants from the surfactant era only now reaching adulthood, it is possible that there is already an unrecognized epidemic of CKD. We suggest individualized, risk-based assessments of premature and LBW infants due to the increased risk of CKD and call for additional research into the long-term risk for CKD these infants face.
Luminescence enhancement of colloidal quantum dots by strain compensation
Authors: Lu Y. , Zhang Y.Q. , Cao X. A.
Published: May 2013

We have investigated the effects of two different strain-relief bilayer shell structures on the luminescent properties of colloidal CdSe quantum dots (QDs). CdSe QDs with a strain-compensated ZnS/ZnCdS bilayer shell were synthesized using the successive ion layer adsorption and reaction technique and their crystallinity of was examined by X-ray diffraction. The QDs enjoyed the benefits of excellent exciton confinement by the ZnS intermediate shell and strain compensation by the ZnCdS outer shell. The resulting CdSe/ZnS/ZnCdS QDs exhibited 40% stronger photoluminescence and a smaller peak redshift upon shell growth compared to conventional CdSe/ZnCdS/ZnS core/shell/shell QDs with an intermediate lattice adaptor. CdSe/ZnS/ZnCdS QD light-emitting diodes (LEDs) had a luminance of 558 cd/m2 at 20 mA/cm2, 28% higher than that of CdSe/ZnCdS/ZnS QD-LEDs. The former also had better spectral purity. These results suggest that nanocrystal shells may be strain-engineered in a different way to achieve QDs of high crystalline and optical quality well suited for full-color display applications.
Strong light emission from stress-activated perovskite-related oxides
Authors: Kamimura Sunao , Yamada Hiroshi , Xu Chao-Nan
Published: May 2013

We report mechanoluminescence (ML) in Sm3+-doped Sr3Sn2O7 phosphors with perovskite-related structure. The ML from Sr3Sn2O7:Sm3+, emitted strong reddish-orange light upon compression, is clearly observable by naked eyes. Based on the comparison between ML spectrum and photoluminescence spectrum, the ML emission was identified to be due to electron transition from an excited state 4G5/2 to the ground state 6HJ (J = 5/2, 7/2, 9/2) in Sm3+ ions. Although the ML emission was gradually decayed as compressive load was applied repeatedly, it recovered completely upon irradiation with UV light (254 nm). This behavior indicating that ML of Sr3Sn2O7:Sm3+ is intimately related to the charge traps. The charge transfer state (CTS) band in the PL excitation spectra was observed for Sr3Sn2O7:Sm3+, indicating that the efficient energy transfer from the host to the Sm3+ ions. The formation of CTS and the charge traps may be responsible for this ML performance.
Plant metabolomics: A new frontier in phytochemical analysis
Authors: Tugizimana Fidele , Piater Lizelle , Dubery Ian
Published: May 2013

The primary and secondary metabolites found in plant cells are the final recipients of biological information flow. In turn, their levels can influence gene expression and protein stability. Qualitative and quantitative measurements of these metabolites reflect the cellular state under defined conditions, and yield critical insights into the cellular processes that control the biochemical phenotype of the cell, tissue or whole organism. Metabolomics differs from traditional targeted phytochemical analysis in various fundamental aspects; for example, it is a data-driven approach with predictive power that aims to assess all measurable metabolites without any pre-conception or pre-selection. As such, metabolomics is providing new dimensions in the study of systems biology, enabling the in-depth understanding of the intra- and extracellular interactions of plant cells. Metabolomics is also developing into a valuable tool that can be used to monitor and assess gene function, and to characterise post-genomic processes from a broad perspective. Here, we give an overview of the fundamental analytical technologies and subsequent multivariate data analyses involved in plant metabolomics as a research tool to study various aspects of plant biology.
first report on meteor-generated seismic signals as detected by the SANSN
Authors: Roelofse Frederick , Saunders Ian
Published: May 2013

A bright meteor with an apparent magnitude of -18 was seen over large parts of southern Africa at ~23:00 South African Standard Time on 21 November 2009. Here we discuss the eye-witness accounts related to the meteor as well as the seismic signals generated by the meteor’s passage through the atmosphere as detected by the Mussina seismograph station forming part of the South African National Seismograph Network. Two signals were identified on the seismogram; the first arrival is interpreted as a precursor coupled seismic wave and the second, which arrived ~138 s after the first, as a directly coupled airwave. The meteor is thought to have entered the atmosphere close to Mussina shortly before 22:55.06 local time, from where it proceeded in a westerly to northwesterly direction with an elevation angle not exceeding 43°. Our results presented here dispel the beliefs of many observers who thought that the meteor must have made landfall very close to their localities. In addition, this contribution documents the first instance of meteor-related seismic signals recorded by the South African National Seismograph Network.
Effects of a Prenatal Care Intervention for Adolescent Mothers on Birth Weight, Repeat Pregnancy, and Educational Outcomes at One Year Postpartum
Authors: Ford Kathleen , Weglicki Linda , Kershaw Trace , Schram Cheryl , Hoyer Paulette J. , Jacobson Mary L.
Published: May 2013

About one-third of adolescent mothers receive inadequate prenatal care, and babies born to young mothers are more likely to be of low birth weight. The objective of this study is to evaluate a peer-centered prenatal care program for adolescent mothers. Pregnant adolescents were randomly assigned to an experimental or control group in a mastery modeling peer-support intervention designed to improve long- and short-term perinatal outcomes. A sample of 282 urban pregnant adolescents (94% African American, 4% Caucasian, 2% other) participated in the study. Participants were recruited from five clinics located mainly in Detroit, Michigan. Participants in the experimental group received care in a small group setting and learned to perform critical measurements with a peer partner during prenatal visits. Participants in the control group received individual prenatal care in the same clinics. Outcome measures included birth weight, years of schooling completed at one year postpartum, planned and unplanned pregnancy at one year postpartum, and employment and school attendance at one year postpartum. Mothers in the experimental group had a lower rate of low birth weight (6.6% vs. 12.5%, p=0.08). The rate of unplanned pregnancy was also lower for adolescents in the experimental group (13.4% vs. 15.9%), although this difference was not statistically significant. Adolescents who participated in the intervention were more likely to have continued their education during the pregnancy and the postpartum year. The mastery modeling, peer-centered, prenatal care program produced some positive pregnancy outcomes for adolescent mothers.
Research Update: Complementary and Alternative Therapies
Authors: Moore Mary Lou
Published: May 2013

Complementary and alternative therapies are increasingly used by many pregnant women in the United States; however, limited research is available on many therapies. The number of studies should increase with the establishment of the National Center for Complementary and Alternative Medicine by the National Institutes of Health. This column reviews recent studies of both herbal medicines and alternative therapies used in pregnancy.
Ask a Lawyer: Making Professional Referrals
Authors: Philipsen Nayna Campbell
Published: May 2013

Lamaze Certified Childbirth Educators have a duty to their clients to make referrals to qualified professionals=min this case, to an expert in nutrition, a dietician. A reasonable way to assure a quality referral is to contact the appropriate professional organization.
Concise Drug Review: Azacitidine and Decitabine
Authors: Derissen Ellen J.B. , Beijnen Jos H. , Schellens Jan H.M.
Published: May 2013

The introduction of the hypomethylating agents azacitidine and decitabine has been a major advancement in the treatment of patients with higher-risk myelodysplastic syndromes, chronic myelomonocytic leukemia, and acute myeloid leukemia who are ineligible for more intensive treatments. This concise drug review summarizes the current state of treatment with azacitidine and decitabine.
Highway routine maintenance carbon dioxide emissions assessment
Authors: Itoya Emioshor , Ison Steve G. , Frost Matthew W. , El-Hamalawi Ashraf , Hazell Katrina
Published: May 2013

Civil infrastructure, including the highway maintenance sector, is under increasing pressure to deliver ‘low-carbon’ services. Reducing this sector's ‘carbon footprint’ can help to meet targets set under the Kyoto Protocol. Carbon dioxide emissions reduction is now a legal requirement under the UK's Climate Change Act; infrastructure clients therefore require their supply chains to provide carbon footprint information. A new, more holistic, project-specific carbon footprinting approach is urgently needed to account for carbon in an integrated manner, identifying areas of carbon hot spots and developing a reduction hierarchy to support business decision making. In this paper a process-based carbon footprinting framework based on the PAS2050:2011 protocol is adopted. Results of case studies (focusing on the carbon footprint) of ‘typical’ UK highway maintenance processes are provided, namely pavement resurfacing, pavement marking, bulk lamp changing and grass cutting. These processes were selected across urban, semi-urban and rural site locations to investigate the significance of these locations on the carbon footprint. The results indicate the robustness of the PAS2050-compliant framework for highway maintenance carbon footprinting; areas of carbon hotspots and related reduction opportunities can be identified to inform the reduction hierarchy across the processes value chain. The research presented can be used as a framework to plan, evaluate and manage highway maintenance programmes and carbon budgets over the maintenance processes value chain.
A constitutive model for compacted expansive and bonded marls
Authors: CARDOSO R. , ALONSO E.E. , MARANHA DAS NEVES E.
Published: May 2013

This paper focuses on understanding the mechanical response of non-saturated compacted marls used to build some motorway embankments in Portugal. The compacted material consists of crushed marls, which can be assumed to be a set of fragments with relatively large dimensions. Experimental studies on the hydromechanical behaviour of this compacted, evolving material show that it behaves as a material in the transition between rockfill (when the fragments can be considered approximately intact) and a clayey soil (when a large number of fragments show strong physical disaggregation). Existing models for compacted rockfill and compacted clayey materials are not adequate to reproduce this complex behaviour. Constitutive models able to reproduce this behaviour are required for predicting the behaviour of earth structures such as these embankments. A model is proposed for the prediction of volumetric deformations for stress and strain boundary conditions corresponding to the oedometric test. It consists of an elasto-plastic unsaturated, double-structure, constitutive model in which the compacted material is assumed to be the macrostructure, and the microstructure is the fragment itself. Owing to the fundamental role of the loss of structure of the marl fragments in global behaviour, a constitutive equation for soft rocks is given, which includes a rule for bond loss depending on suction. Good results are obtained when the model is used to reproduce experimental tests performed on samples of compacted marls to which stress and suction cycles are applied. Other than the model proposed in this paper, attempts to reproduce the behaviour of compacted soft rocks are unknown.
Chloride penetration in concrete subject to wet/dry cycling: influence of moisture content
Authors: Arya Chanakya , Bioubakhsh Samira , Vassie Perry
Published: May 2013

Concrete structures suffer from corrosion if chloride ions in the environment penetrate to the depth of reinforcing steel; surfaces periodically wetted with chloride solution are at most risk, when chloride ions can enter concrete by combined diffusion and absorption. BS8500-1 recommended minimum cover requirements primarily assume that chloride ingress is diffusion controlled, and absorption is only partly accounted for, so cover values may be inadequate. This paper investigates factors that influence absorption of chloride ions into concrete and how this affects distribution of chloride at different depths from the surface. Concrete cubes (CEM I cement; water/cement ratio 0·45) are subjected to repeated wetting (with 50% saturated salt solution) and drying cycles, during which their mass is monitored. The effective porosity, weight and distance sorptivity and chloride penetration depths are calculated for a number of curing, conditioning and drying conditions. Samples are extracted from the cubes at a range of depths and analysed for chloride content. Results show that the quantity of chloride entering the concrete, and in particular surface chloride content, is very sensitive to effective porosity/drying conditions immediately before wetting; also as much as 31% of the protection provided by concrete cover can be lost after exposure to just one wet/dry cycle, thereby significantly reducing time to corrosion of concrete structures.
Adrenaline Autoinjector Needle Interlocking in the Thumb Due to Improper Injection
Authors: M Schmid , I Weidenhoffer , A Udvardi , K Lomoschitz , B Volc-Platzer , S Wöhrl
Published: May 2013

Herein, a case of improper epinephrine autoinjector injection into the thumb involving deep connective tissue
and bone is reported. We additionally review knowledge, skills and habits of a cohort of autoinjector users of a hospitalbased
dermatologic outpatient clinic.
Strengthening Tpack: A Broader Notion of Context and the Use of Teacher's Narratives to Reveal Knowledge Construction
Authors: Porras-Hernández Laura Helena , Salinas-Amescua Bertha
Published: May 2013

Technological Pedagogical Content Knowledge (TPACK) as a framework to understand and foster teachers' knowledge for efficient technology integration has the value of unveiling new types of knowledge and departing from technocentric approaches. In this article, we consider two approaches to advance this framework. One of these opens the discussion on a more complex conception of context, along two dimensions: scope and actor. The second is an example of how TPACK can be useful in the phenomenological approaches of teachers reflecting on their practice using narratives in the tradition of European and Latin-American bodies of knowledge on systematization.
Interleukin-18 Activates Skeletal Muscle AMPK and Reduces Weight Gain and Insulin Resistance in Mice
Authors: Lindegaard Birgitte , Matthews Vance B. , Brandt Claus , Hojman Pernille , Allen Tamara L. , Estevez Emma , Watt Matthew J. , Bruce Clinton R. , Mortensen Ole H. , Syberg Susanne , Rudnicka Caroline , Abildgaard Julie , Pilegaard Henriette , Hidalgo Juan , Ditlevsen Susanne , Alsted Thomas J. , Madsen Andreas N. , Pedersen Bente K. , Febbraio Mark A.
Published: May 2013

Circulating interleukin (IL)-18 is elevated in obesity, but paradoxically causes hypophagia. We hypothesized that IL-18 may attenuate high-fat diet (HFD)-induced insulin resistance by activating AMP-activated protein kinase (AMPK). We studied mice with a global deletion of the α-isoform of the IL-18 receptor (IL-18R−/−) fed a standard chow or HFD. We next performed gain-of-function experiments in skeletal muscle, in vitro, ex vivo, and in vivo. We show that IL-18 is implicated in metabolic homeostasis, inflammation, and insulin resistance via mechanisms involving the activation of AMPK in skeletal muscle. IL-18R−/− mice display increased weight gain, ectopic lipid deposition, inflammation, and reduced AMPK signaling in skeletal muscle. Treating myotubes or skeletal muscle strips with IL-18 activated AMPK and increased fat oxidation. Moreover, in vivo electroporation of IL-18 into skeletal muscle activated AMPK and concomitantly inhibited HFD-induced weight gain. In summary, IL-18 enhances AMPK signaling and lipid oxidation in skeletal muscle implicating IL-18 in metabolic homeostasis.
Changes in Body Fat Distribution and Fitness Are Associated With Changes in Hemoglobin A1c After 9 Months of Exercise Training
Authors: Sénéchal Martin , Swift Damon L. , Johannsen Neil M. , Blair Steven N. , Earnest Conrad P. , Lavie Carl J. , Church Timothy S.
Published: May 2013

OBJECTIVE

To investigate the associations between changes in body composition and fitness after exercise training and changes in hemoglobin A1c (HbA1c) in individuals with type 2 diabetes.

RESEARCH DESIGN AND METHODS

Participants (n = 201) were randomized to aerobic, resistance, or combined training for 9 months. HbA1c, waist circumference, total and trunk fat mass, appendicular fat mass, lean body mass, isokinetic leg muscle strength, peak O2 uptake, and estimated METs were assessed at baseline and follow-up. Change in HbA1c was evaluated across quartiles of change in body composition and fitness.

RESULTS

Change in HbA1c was associated with changes in body weight (r = 0.13, P = 0.052), waist circumference (r = 0.17, P = 0.013), trunk fat mass (r = 0.19, P = 0.005), and estimated METs (r = −0.16, P = 0.023). There was a trend in change in HbA1c across quartiles of waist circumference (P = 0.011), trunk fat mass (P = 0.020), and estimated METs (P = 0.011). Participants with increased estimated METs and reduced trunk fat mass had greater odds of having reduced HbA1c after training (3.48, 1.46–8.31). Finally, participants with increased estimated METs and reduced waist circumference were 2.81 (1.13–6.98) times more likely to have reduced HbA1c and type 2 diabetes medication use than those without improved fitness and central adiposity.

CONCLUSIONS

In patients with type 2 diabetes, a reduction in central adiposity and increase in fitness were the most prominent predictors of the change in HbA1c in response to exercise training.
Effects of Low-Dose Prednisolone on Hepatic and Peripheral Insulin Sensitivity, Insulin Secretion, and Abdominal Adiposity in Patients With Inflammatory Rheumatologic Disease
Authors: Petersons Carolyn J. , Mangelsdorf Brenda L. , Jenkins Arthur B. , Poljak Anne , Smith Malcolm D. , Greenfield Jerry R. , Thompson Campbell H. , Burt Morton G.
Published: May 2013

OBJECTIVE

The metabolic effects of low-dose prednisolone and optimal management of glucocorticoid-induced diabetes are poorly characterized. The aims were to investigate the acute effects of low-dose prednisolone on carbohydrate metabolism and whether long-term low-dose prednisolone administration increases visceral adiposity, amplifying metabolic perturbations.

RESEARCH DESIGN AND METHODS

Subjects with inflammatory rheumatologic disease without diabetes mellitus were recruited. Nine subjects (age, 59 ± 11 years) not using oral glucocorticoids were studied before and after a 7- to 10-day course of oral prednisolone 6 mg daily. Baseline data were compared with 12 subjects (age, 61 ± 8 years) using continuous long-term prednisolone (6.3 ± 2.2 mg/day). Basal endogenous glucose production (EGP) was estimated by 6,6-2H2 glucose infusion, insulin sensitivity was estimated by two-step hyperinsulinemic-euglycemic clamp, insulin secretion was estimated by intravenous glucose tolerance test, and adipose tissue areas were estimated by computed tomography.

RESULTS

Prednisolone acutely increased basal EGP (2.44 ± 0.46 to 2.65 ± 0.35 mg/min/kg; P = 0.05) and reduced insulin suppression of EGP (79 ± 7 to 67 ± 14%; P = 0.03), peripheral glucose disposal (8.2 ± 2.4 to 7.0 ± 1.6 mg/kg/min; P = 0.01), and first-phase (5.9 ± 2.0 to 3.9 ± 1.6 mU/mmol; P = 0.01) and second-phase (4.6 ± 1.7 to 3.6 ± 1.4 mU/mmol; P = 0.02) insulin secretion. Long-term prednisolone users had attenuated insulin suppression of EGP (66 ± 14 vs. 79 ± 7%; P = 0.03) and nonoxidative glucose disposal (44 ± 24 vs. 62 ± 8%; P = 0.02) compared with nonglucocorticoid users, whereas basal EGP, insulin secretion, and adipose tissue areas were not significantly different.

CONCLUSIONS

Low-dose prednisolone acutely perturbs all aspects of carbohydrate metabolism. Long-term low-dose prednisolone induces hepatic insulin resistance and reduces peripheral nonoxidative glucose disposal. We conclude that hepatic and peripheral insulin sensitivity should be targeted by glucose-lowering therapy for glucocorticoid-induced diabetes.