bluuebunny/crossref_metadata_2025 huggingface dataset:
The Isolation of Bifidobacteria from Occlusal Carious Lesions in Children and Adults
Authors: Mantzourani M. , Gilbert S.C. , Sulong H.N.H. , Sheehy E.C. , Tank S. , Fenlon M. , Beighton D.
Published: June 2009

The aim of this study was to enumerate and identify bifidobacteria from occlusal carious lesions in permanent and deciduous teeth. Samples of infected dentine were obtained from 24 active occlusal lesions in deciduous teeth and from 15 occlusal lesions in permanent teeth. Plaque samples from sound occlusal surfaces of 12 caries-free adults and 12 children were also obtained. The bifidobacterial strains were isolated in mupirocin-containing selective media, Gram-stained and subcultured for identification. Total bacterial counts were determined using fastidious anaerobic agar, and isolates were identified using genus-specific PCR primers and were confirmed by 16S rRNA sequencing. Bifidobacteria were isolated from 13 of the 15 occlusal lesions in the adults and formed 5.09 ± 2.11% of the total cultivable flora. In the children, bifidobacteria were isolated from 16 of the 24 occlusal lesions and formed 7.4 ± 2.6% of the total flora. No bifidobacteria were isolated from the occlusal surfaces of caries-free adults or children. A total of 424 bifidobacteria were identified and these were Bifidobacteriumdentium, Parascardovia denticolens, Scardoviainopicata, Bifidobacterium longum,Scardovia genomosp. C1 and Bifidobacterium breve. B. dentium was present in 14 out of the 16 bifidobacteria-positive samples from the lesions on the deciduous teeth and in 7 out of the 13 positive lesions in adults (p = 0.04). The present data suggest that bifidobacteria may play a role in the progression of occlusal caries lesions in both children and adults.
Acute Hyperglycemia and Early Hemorrhagic Transformation in Ischemic Stroke
Authors: Paciaroni Maurizio , Agnelli Giancarlo , Caso Valeria , Corea Francesco , Ageno Walter , Alberti Andrea , Lanari Alessia , Micheli Sara , Bertolani Luca , Venti Michele , Palmerini Francesco , Billeci Antonia M.R. , Comi Giancarlo , Previdi Paolo , Silvestrelli Giorgio
Published: June 2009

Background: Hyperglycemia has been claimed to be associated with hemorrhagic transformation (HT) in patients with acute ischemic stroke treated with thrombolysis. The aim of this study was to assess whether the admission blood glucose level is related to HT in a prospective study in consecutive patients with acute ischemic stroke. Methods: Consecutive patients admitted for ischemic stroke to 4 Italian hospitals were included in this prospective cohort study. Results: Among 1,125 consecutive patients included in the analysis, 98 (8.7%) had HT: 62 (5.5%) had hemorrhagic infarction (HI) and 36 (3.2%) parenchymal hematoma (PH). A blood glucose level >110 mg/dl was found in 42.4% of the patients, a level between 110 and 149 mg/dl in 25.2%, and a level >150 mg/dl in 17.2%. At 3 months, 7 patients were lost at follow-up, 326 patients (29.2%) were disabled (modified Rankin score ≥3) and 129 died (11.5%). PH was associated with an increased risk of death or disability (OR 15.29, 95% CI 2.35–99.35). However, this was not the case for HT overall and HI. At logistic regression analysis, PH was predicted by high levels of admission blood glucose (OR 1.01, 95% CI 1.00–1.01 for 1 added mg/dl). The rate of PH was 2.1% in patients with <110 mg/dl, 3.6% in patients with a level between 110 and 149 mg/dl and 6.4% in patients with a level >150 mg/dl. The curve estimation regression model showed a significant linear increase in the risk of PH related to an increase in blood glucose levels (R2 = 0.007, p = 0.007). Conclusions: Hyperglycemia during acute ischemic stroke predisposes to PH, which in turn determines a nonfavorable outcome at 3 months. This relationship seems to be linear.
Cardiac Muscle Ring Finger-1 Increases Susceptibility to Heart Failure In Vivo
Authors: Willis Monte S. , Schisler Jonathan C. , Li Luge , Rodríguez Jessica E. , Hilliard Eleanor G. , Charles Peter C. , Patterson Cam
Published: June 2009

Muscle ring finger (MuRF)1 is a muscle-specific protein implicated in the regulation of cardiac myocyte size and contractility. MuRF2, a closely related family member, redundantly interacts with protein substrates and heterodimerizes with MuRF1. Mice lacking either MuRF1 or MuRF2 are phenotypically normal, whereas mice lacking both proteins develop a spontaneous cardiac and skeletal muscle hypertrophy, indicating cooperative control of muscle mass by MuRF1 and MuRF2. To identify the unique role that MuRF1 plays in regulating cardiac hypertrophy in vivo, we created transgenic mice expressing increased amounts of cardiac MuRF1. Adult
MuRF1
transgenic (Tg
+
) hearts exhibited a nonprogressive thinning of the left ventricular wall and a concomitant decrease in cardiac function. Experimental induction of cardiac hypertrophy by transaortic constriction (TAC) induced rapid failure of
MuRF1 Tg
+
hearts. Microarray analysis identified that the levels of genes associated with metabolism (and in particular mitochondrial processes) were significantly altered in
MuRF1 Tg
+
hearts, both at baseline and during the development of cardiac hypertrophy. Surprisingly, ATP levels in
MuRF1 Tg
+
mice did not differ from wild-type mice despite the depressed contractility following TAC. In comparing the level and activity of creatine kinase (CK) between wild-type and
MuRF1 Tg
+
hearts, we found that mCK and CK-M/B protein levels were unaffected in
MuRF1 Tg
+
hearts; however, total CK activity was significantly inhibited. We conclude that increased expression of cardiac MuRF1 results in a broad disruption of primary metabolic functions, including alterations in CK activity that leads to increased susceptibility to heart failure following TAC. This study demonstrates for the first time a role for MuRF1 in the regulation of cardiac energetics in vivo.
High Risk of Early Neurological Recurrence in Symptomatic Carotid Stenosis
Authors: Ois Angel , Cuadrado-Godia Elisa , Rodríguez-Campello Ana , Jimenez-Conde Jordi , Roquer Jaume
Published: June 2009

Background and Purpose—

Few data are available on very early stroke recurrence evaluated within the first hours after onset of symptoms and outcome for unselected patients with first-ever mild stroke or TIA and symptomatic carotid stenosis ≥50%.

Methods—

One hundred sixty-three patients with symptomatic carotid stenosis and initial mild stroke (121) or TIA (42) were evaluated within 6 hours from onset of symptoms in a single tertiary hospital. Neurological recurrence (NR) was defined as a clearly defined new neurological event (TIA or stroke) or an increase of 4 points in the initial NIHSS. The NR rate was determined at 72 hours, 7 days, and 14 days. Disability was defined as a score of 3 to 6 on the modified Rankin scale at 14 days.

Results—

Forty-five patients (27.6%) had NR, including 6 patients with 2 episodes in different time periods: 34 (20.9%) within the first 72 hours; 11 (6.7%) between 72 hours and 7 days; and 6 (3.7%) at 14 days. Only carotid stenosis ≥70% was associated with NR; diabetes was marginally associated. At 2 weeks, 19 patients (11.7%) had disability; 14 of them experienced NR in the first 72 hours.

Conclusions—

Patients with first-ever mild stroke or TIA and symptomatic carotid stenosis are at high risk for NR, especially within the first 72 hours. Our results suggest the necessity of testing pharmacological or interventional strategies for use during the hyperacute stroke phase in these patients.
Promoting Reconciliation Through the Satisfaction of the Emotional Needs of Victimized and Perpetrating Group Members: The Needs-Based Model of Reconciliation
Authors: Shnabel Nurit , Nadler Arie , Ullrich Johannes , Dovidio John F. , Carmi Dganit
Published: June 2009

Guided by the Needs-Based Model of Reconciliation, we hypothesized that being a member of a victimized group would be associated with a threat to the status and power of one's ingroup, whereas being a member of a perpetrating group would threaten the image of the ingroup as moral and socially acceptable. A social exchange interaction through which victims feel empowered by their perpetrators and perpetrators feel accepted by their victims was thus predicted to enhance the parties' willingness to reconcile. Supporting the predictions across two experiments, members of the perpetrator group (Jews in Study 1 and Germans in Study 2) showed greater willingness to reconcile when they received a message of acceptance, rather than empowerment, from a member of the victimized group. Members of the victimized group (Arabs in Study 1 and Jews in Study 2) demonstrated the opposite effect. Applied and theoretical implications of these results are discussed.
More-than-human social geographies: posthuman and other possibilities
Authors: Panelli Ruth
Published: June 2009

While ‘the social’ is problematized in diverse ways in current geographical debates this report reflects on the ongoing relevance of social geographies, especially those that attend to the complexity and interconnectivity of life. This review outlines three ways in which society-nature relations are being interrogated via: poststructural, posthuman and Indigenous foci. It concludes that important questions of social difference and unequal power relations remain relevant for more-than-human geographies.
Landholding and Fertility in Korea: 1914-1925
Authors: Kim Kuentae , Park Hyunjoon
Published: June 2009

By matching the population registers with the land tax roster, the authors examine how a family's socioeconomic status, represented by the size of landholding, affected fertility behaviors among Korean women in a village of Jeju Island for the period from 1914 to 1925. Landholding is an important indicator of a family's socioeconomic condition, especially for this historical population, the majority of whom were engaged in agricultural work. The authors' discrete-time event history model shows that women in households with larger landholding sizes had a greater risk of birth than their counterparts in households with smaller landholding sizes. However, the relationship is not linear, showing no significant difference between the two highest groups of landholding. The authors interpret the nonlinear relationship in light of economic and agricultural conditions of the island. They highlight potential contributions of their findings for historical studies of population and families in East Asia.
Minimal Detectable Change Scores for the Wolf Motor Function Test
Authors: Fritz Stacy L. , Blanton Sarah , Uswatte Gitendra , Taub Edward , Wolf Steven L.
Published: June 2009

Background. The Wolf Motor Function Test (WMFT) is an impairment-based test whose psychometrics have been examined by previous reliability and validity studies. Standards for evaluating whether a given change is meaningful, however, have not yet been addressed. Objectives. To determine the standard error of measurement (SEM) and minimal detectable change (MDC) for the WMFT. Methods. Data were collected from 6 university laboratories that participated in the EXCITE national clinical trial and included 96 individuals with sub-acute stroke (3—9 months). Measurements were made by blinded evaluators who were trained and standardized to administer the WMFT, which was completed on 2 occasions 2 weeks apart. No intervention was given between testing sessions. Results. The WMFT Performance Time score has a SEM of 0.2 seconds and a MDC95 of 0.7 seconds. The individual task timed items MDC 95 ranged from 1.0 second (turn key in lock) to 3.4 seconds (reach and retrieve) with individual task items demonstrating notablly higher variability than the average WMFT Performance Time. The average WMFT Functional Ability Scale SEM and MDC95 is 0.1 points. Conclusions. When assessing the effect of a therapeutic intervention, if an individual experiences an amount of change equal to or greater than the MDC, then one may be 95% confident that this margin of change is truly larger than measurement error and not a chance result. Thus, the determination of SEM and MDC in outcome assessments allows researchers and clinicians to distinguish which results are actual differences versus which results are simply changes resulting from error or chance.
Treatment with anti-FasL antibody preserves memory lymphocytes and virus-specific cellular immunity in macaques challenged with simian immunodeficiency virus
Authors: Poonia Bhawna , Salvato Maria S. , Yagita Hideo , Maeda Toshihiro , Okumura Ko , Pauza C. David
Published: June 2009

Immune deficiency viruses such as SIV in macaques or HIV-1 in human beings have evolved mechanisms to defeat host immunity that also impact the efficacy of vaccines. A key factor for vaccine protection is whether immune responses elicited by prior immunization remain at levels sufficient to limit disease progression once a host is exposed to the pathogen. One potential mechanism for escaping pre-existing immunity is to trigger death among antigen-activated cells. We tested whether FasL/CD178 is involved in destroying preexisting immunity. Rhesus macaques were immunized with recombinant vesicular stomatitis virus vaccine expressing SIV Gag to elicit cellular immune responses, then treated with antibody that neutralizes FasL and challenged with intravenous SIVmac251. Compared with animals injected with control antibody, anti-FasL–treated macaques had superior preservation of central memory CD4+ and CD8+ cells and decreased regulatory T cells in the blood. The CD4+ and CD8+ lymphocytes from treated animals responded better to SIV Gag compared with controls, evidenced by higher cell-mediated immune responses to viral antigens for at least 17 weeks after SIV challenge. Anti-FasL treatment during the initial stages of acute SIV infection preserved the T-cell compartment and sustained cell-mediated immunity to SIV.
Insulin-Like Growth Factor Binding Protein-1 in the Ruminant Uterus: Potential Endometrial Marker and Regulator of Conceptus Elongation
Authors: Simmons Rebecca M. , Erikson David W. , Kim Jinyoung , Burghardt Robert C. , Bazer Fuller W. , Johnson Greg A. , Spencer Thomas E.
Published: June 2009

Establishment of pregnancy in ruminants requires conceptus elongation and production of interferon-τ (IFNT), the pregnancy recognition signal that maintains ovarian progesterone (P4) production. These studies determined temporal and spatial alterations in IGF binding protein (IGFBP)-1 and IGFBP3 in the ovine and bovine uterus; effects of P4 and IFNT on their expression in the ovine uterus; and effects of IGFBP1 on ovine trophectoderm cell proliferation, migration, and attachment. IGFBP1 and IGFBP3 were studied because they are the only IGFBPs specifically expressed by the endometrial luminal epithelia in sheep. In sheep, IGFBP1 and IGFBP3 expression was coordinate with the period of conceptus elongation, whereas only IGFBP1 expression was coordinate with conceptus elongation in cattle. IGFBP1 mRNA in the ovine endometria was between 5- and 29-fold more abundant between d 12 and 16 of pregnancy compared with the estrous cycle and greater on d 16 of pregnancy than nonpregnancy in the bovine uterus. In sheep, P4 induced and IFNT stimulated expression of IGFBP1 but not IGFBP3; however, the effect of IFNT did not mimic the abundant increase observed in pregnant ewes. Therefore, IGFBP1 expression in the endometrium is regulated by another factor from the conceptus. IGFBP1 did not affect the proliferation of ovine trophectoderm cells in vitro but did stimulate their migration and mediate their attachment. These studies reveal that IGFBP1 is a common endometrial marker of conceptus elongation in sheep and cattle and most likely regulates conceptus elongation by stimulating migration and attachment of the trophectoderm.
Carcinogenic Effects of Exogenous and Endogenous Glucagon-Like Peptide-2 in Azoxymethane-Treated Mice
Authors: Iakoubov Roman , Lauffer Lina M. , Trivedi Shivangi , Kim Young-In J. , Brubaker Patricia L.
Published: June 2009

Glucagon-like peptide-2 (GLP-2) is a nutrient-dependent intestinotropic hormone that promotes intestinal growth, via increased intestinal proliferation and decreased apoptosis, as well as increases in nutrient absorption and barrier function. The long-acting analog h(Gly2)GLP-2[1-33] is currently being tested for treatment of short bowel syndrome and Crohn’s disease. However, the role of GLP-2 in colon carcinogenesis is controversial. To assess the intestinotropic effects of exogenous and endogenous GLP-2, C57BL6/J mice were injected with 1μg h(Gly2)GLP-2[1-33]; 30 or 60 ng hGLP-2[3-33], a GLP-2 receptor antagonist; or PBS (4 wk, twice a day, sc). Chronic h(Gly2)GLP-2[1-33] increased small intestinal weight/body weight (P < 0.001), villus height (P < 0.001), crypt depth (P < 0.001), and crypt cell proliferation, as measured by expression of the proliferative marker Ki67 (P < 0.05–0.01). In contrast, chronic hGLP-2[3-33] decreased small intestinal weight/body weight (P < 0.05) and colon weight/body weight (P < 0.05). To assess the carcinogenic effects of endogenous and exogenous GLP-2, separate mice were injected with azoxymethane (10 mg/kg, 4 wk, every 7 d, ip), followed by 1.5 μg h(Gly2)GLP-2[1-33], 30 ng hGLP-2[3-33], or PBS (4 wk, twice a day, sc) 2 or 12 wk thereafter. At 10 or 46 wk after azoxymethane treatment, the numbers of aberrant crypt foci increased with h(Gly2)GLP-2[1-33] (P < 0.001) and decreased with hGLP-2[3-33] (P < 0.01–0.05) treatment. Furthermore, mucin-depleted aberrant foci, consistent with progressive dysplasia, were almost exclusively present in h(Gly2)GLP-2[1-33]-treated mice (P < 0.01–0.001). Additionally, adenocarcinomas developed in h(Gly2)GLP-2[1-33]-treated mice but not in those receiving hGLP-2[3-33] or PBS. Taken together, these studies indicate that chronic treatment with GLP-2 enhances colon carcinogenesis, whereas antagonism of the GLP-2 receptor decreases dysplasia, with possible implications for human therapy.
The p38 Mitogen-Activated Protein Kinase Regulates 11β-Hydroxysteroid Dehydrogenase Type 2 (11β-HSD2) Expression in Human Trophoblast Cells through Modulation of 11β-HSD2 Messenger Ribonucleic Acid Stability
Authors: Sharma Anju , Guan Haiyan , Yang Kaiping
Published: June 2009

The placental 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2; encoded by the HSD11B2 gene) has emerged as a key player in controlling fetal development, but its regulation is incompletely understood. Here we identified p38 MAPK as an important regulator of placental 11β-HSD2. We showed that inhibition of p38 MAPK with the pharmacological inhibitor SB202190 led to an approximately 50% reduction in 11β-HSD2 activity, protein, and mRNA in primary human placental trophoblast cells. Furthermore, the effect of SB202190 was confirmed by the use of two additional p38 inhibitors, SB203580 and SB220025. In addition, SB202190 decreased the half-life of 11β-HSD2 mRNA without altering the HSD11B2 promoter activity, indicating that p38 MAPK regulates placental 11β-HSD2 expression through modulation of 11β-HSD2 mRNA stability. Importantly, small interfering RNA-mediated knockdown of p38α caused a 50% reduction in 11β-HSD2 activity, suggesting that p38α is the primary p38 isoform involved. Taken together, these findings suggest a novel pathway controlling placental 11β-HSD2 expression resulting from the activation of p38 MAPK. Given that p38α is abundantly expressed in the human placenta in which its function is largely unknown, our present study also reveals 11β-HSD2 as an important target through which p38α may regulate human placental function and consequently fetal growth and development.
Somatic cAMP signaling regulates MSP-dependent oocyte growth and meiotic maturation inC. elegans
Authors: Govindan J. Amaranath , Nadarajan Saravanapriah , Kim Seongseop , Starich Todd A. , Greenstein David
Published: June 2009

Soma-germline interactions control fertility at many levels, including stem cell proliferation, meiosis and gametogenesis, yet the nature of these fundamental signaling mechanisms and their potential evolutionary conservation are incompletely understood. In C. elegans, a sperm-sensing mechanism regulates oocyte meiotic maturation and ovulation, tightly coordinating sperm availability and fertilization. Sperm release the major sperm protein (MSP)signal to trigger meiotic resumption (meiotic maturation) and to promote contraction of the follicle-like gonadal sheath cells that surround oocytes. Using genetic mosaic analysis, we show that all known MSP-dependent meiotic maturation events in the germline require Gαs-adenylate cyclase signaling in the gonadal sheath cells. We show that the MSP hormone promotes the sustained actomyosin-dependent cytoplasmic streaming that drives oocyte growth. Furthermore, we demonstrate that efficient oocyte production and cytoplasmic streaming require Gαs-adenylate cyclase signaling in the gonadal sheath cells, thereby providing a somatic mechanism that coordinates oocyte growth and meiotic maturation with sperm availability. We present genetic evidence that MSP and Gαs-adenylate cyclase signaling regulate oocyte growth and meiotic maturation in part by antagonizing gap-junctional communication between sheath cells and oocytes. In the absence of MSP or Gαs-adenylate cyclase signaling, MSP binding sites are enriched and appear clustered on sheath cells. We discuss these results in the context of a model in which the sheath cells function as the major initial sensor of MSP, potentially via multiple classes of G-protein-coupled receptors. Our findings highlight a remarkable similarity between the regulation of meiotic resumption by soma-germline interactions in C. elegans and mammals.
Adenomatous polyposis coliregulatesDrosophilaintestinal stem cell proliferation
Authors: Lee Wen-Chih , Beebe Katherine , Sudmeier Lisa , Micchelli Craig A.
Published: June 2009

Adult stem cells define a cellular reserve with the unique capacity to replenish differentiated cells of a tissue throughout an organism's lifetime. Previous analysis has demonstrated that the adult Drosophila midgut is maintained by a population of multipotent intestinal stem cells (ISCs) that resides in epithelial niches. Adenomatous polyposis coli(Apc), a tumor suppressor gene conserved in both invertebrates and vertebrates, is known to play a role in multiple developmental processes in Drosophila. Here, we examine the consequences of eliminating Apc function on adult midgut homeostasis. Our analysis shows that loss of Apc results in the disruption of midgut homeostasis and is associated with hyperplasia and multilayering of the midgut epithelium. A mosaic analysis of marked ISC cell lineages demonstrates that Apc is required specifically in ISCs to regulate proliferation, but is not required for ISC self-renewal or the specification of cell fate within the lineage. Cell autonomous activation of Wnt signaling in the ISC lineage phenocopied Apc loss and Apc mutants were suppressed in an allele-specific manner by abrogating Wnt signaling, suggesting that the effects of Apc are mediated in part by the Wnt pathway. Together,these data underscore the essential requirement of Apc in exerting regulatory control over stem cell activity, as well as the consequences that disrupting this regulation can have on tissue homeostasis.
Enhancement of Mechanical Properties Upon Hydration in Copolymers of PEG and Iodinated Tyrosine-derived Poycarbonates
Authors: Bedoui F. , Widjaja L. K. , Luk A. , Bolikal D. , Murthy N. S. , Kohn J.
Published: June 2009

Increase in modulus upon hydration in copolymers of desaminotyrosyl-tyrosine ethyl ester (DTE) and poly(ethylene glycol) (PEG) with iodinated tyrosines, poly(I2DTE-co-PEG carbonate)s, was investigated by varying the fraction and the molecular weight of the hydrophilic PEG component. Water, as expected, acts as plasticizer in polymer with PEG content < 15 wt% and > 30 wt%. But, water has the opposite effect in iodinated polymers with moderate PEG contents, between 15 to 20 wt%: it enhances the Young's modulus. The strength and modulus of hydrated poly(I2DTE-co-15%PEG2K carbonate)s increased by as much as fifteen fold upon hydration. While the decrease in the mechanical properties in most polymeric materials with diluents such water is due to the solvent-induced swelling, the increase in strength and modulus that is observed is most likely due to the reinforcing effect of the increased cross-linking efficiency of the hydrated PEG domains in the iodinated polymer.
Thermodynamics and Kinetics for Suppression of GeO Desorption by High Pressure Oxidation of Ge
Authors: Nagashio Kosuke , Lee C. H. , Nishimura T. , Kita K. , Toriumi A.
Published: June 2009

We analyze a main scheme for the suppression of GeO desorption by the high pressure oxidation which drastically improve the electrical quality of Ge/GeO2 capacitors. The inherent driving force for GeO to form at the Ge/GeO2 interface and to diffuse toward the GeO2 surface was realized by the concentration gradient in the GeO2 film, which was obtained from the thermodynamic calculation. Kinetic consideration based on the comparison with Si/SiO2 stacks suggests that GeO desorption at the GeO2 surface is the rate-limiting process under passive oxidation conditions. When O2 pressure is increased by high pressure oxidation, the vapor pressure of GeO at the GeO2 surface is reduced, restricting GeO desorption at the GeO2 surface.
Studies of Non-Proportionality in Alkali Halide and Strontium Iodide Scintillators Using SLYNCI
Authors: Ahle Larry , Bizarri Gregory , Cherepy Nerine , Choong Woon-Seng , Moses William W. , Payne S A , Sheets Steven , Sturm Benjamin W.
Published: June 2009

Recently a collaboration of LLNL and LBNL has constructed a second generation Compton coincidence instrument to study the non-proportionality of scintillators [1]. This device, known as SLYNCI (Scintillator Light-Yield Non-proportionality Characterization Instrument), has an over 30 time higher data collection rate than previous devices enabling complete characterization of a sample with less 24 hours of running time. Thus, SLYNCI enables a number of systematic studies of scintillators as many samples can be processed in a reasonable length of time. The studies include difference in non-proportionality between different types of scintillators, different members of the same family of scintillators, and impact of different doping levels. The results of such recent studies are presented here, including a study on of various alkali halides, and the impact of europium doping level in strontium iodide. Directions of future work will also be discussed.
Electroluminescence imaging of Cu(In,Ga)Se2 thin film modules
Authors: Rau Uwe , Kirchartz Thomas , Helbig Anke , Pieters Bart Elger
Published: June 2009

Electroluminescence images gained from Cu(In,Ga)Se2 mini-modules under different voltage bias conditions are investigated. The mini-modules of area 20 × 20 cm2 with 42 cells exhibit typically 10-20 localized shunts. The consequences of these shunts on the performance of the individual cells and of the entire module are analyzed quantitatively by evaluating the electroluminescence images. Our evaluation method uses the fact that the electroluminescence intensity at each position in each cell within the module depends on the actual voltage drop over the junction at this specific location. Thus, the analysis of the electroluminescence intensity allows us to reconstruct the current/voltage characteristics of all individual cells in the module. In addition, we provide first simulations using a distributed diode network model to quantitatively explain the experimental results.
Chemical Composition and Electronic Properties of CuInS2/Zn(S,O) Interfaces
Authors: Sáez-Araoz Rodrigo , Lauermann Iver , Neisser Axel , Lux-Steiner Martha Ch , Ennaoui Ahmed
Published: June 2009

We report on the chemical deposition and electronic properties of CuInS2/Zn(S,O) interfaces. The Zn(S,O) buffer was grown by a new chemical bath deposition (CBD) process that allows the tailoring of the S/O ratio in the films. Resulting Zn(S,O) films exhibit transparencies above 80% (for λ>390 nm) and an optical energy band gap of 3.9 eV which decreases to 3.6 eV after annealing in air at 200°C. Production line CuInS2 (CIS) absorbers provided by Sulfurcell Solartechnik GmbH are used as substrates for the investigation of the CIS/Zn(S,O) interface and the chemical composition of Zn(S,O). A ZnS/(ZnS+ZnO) ratio of 0.5 is found by X-ray photoelectron spectroscopy and X-ray excited Auger electron spectroscopy (XPS and XAES). The valence band offset between the heterojunction partners (ΔEV = 1.8 ± 0.2 eV) has been determined by means of XPS and ultraviolet photoelectron spectroscopy (UPS). Considering the energy band gap of the CIS absorber and the measured band gap of Zn(S,O), the conduction band offset (ΔEC) is calculated as: resulting in a spike of 0.5±0.3 eV in the conduction band at the heterojunction before annealing. After the heat treatment, the valence band offset is reduced to 1.5±0.2 eV and the calculated conduction band offset remains at 0.5±0.3 eV.
A Rapid Screening Method for Investigating the Effect of Processing Parameters on CdTe/CdS Solar Cell Performance
Authors: Al Turkestani Mohammed , Durose Ken , Wakeling Ben , Lane David , Irvine Stuart , Barrioz Vincent
Published: June 2009

A rapid screening method is reported in which material processing parameters are investigated as a function of the CdTe absorber thickness in CdTe/CdS solar cells. It has been used to investigate i) the optimum absorber thickness for CdCl2 processing at 380°C for 10 mins, and ii) the effect on device performance of post-growth annealing of CdS layer with H2, N2, and O2. It was found that the optimum thickness of CdTe compatible with the processing was ∼3μm. The device results were independent of the post-growth treatment of the CdS for the conditions investigated here. The bevel method allowed for ∼30 data points to be obtained from each sample, this giving a significant advantage over conventional experimental methods.
Recent Advances in the STM-based Luminescence Microscopy of Cu(In,Ga)Se2 thin films
Authors: Romero Manuel J. , Contreras Miguel A. , Repins Ingrid , Jiang Chun-Sheng , Al-Jassim Mowafak
Published: June 2009

We report on recent advances in the development of a luminescence spectroscopy based on scanning tunneling microscopy (STM) and its application to fundamental aspects of Cu(In,Ga)Se2 (CIGS) thin films. Relevant to our discussion is the specifics of the surface electronics. The CIGS shows pronounced stoichiometric deviations at the surface and, consequently, distinct surface electronics that has been shown to be critical in achieving high efficiency. Cathodoluminescence (CL), a luminescence spectrum imaging mode in scanning electron microscopy (SEM), provides a direct correlation between the microstructure of the CIGS and its electronic properties. As such, cathodoluminescence can resolve the emission spectrum between grain boundaries and grain interiors or be used to investigate the influence of local orientation and stoichiometry on the electronic properties of the CIGS at the microscale. Cathodoluminescence is not a surface microscopy, however, and resolving the electronic structure of the CIGS surface remains elusive to all luminescence microscopies. With this motivation, we have developed a luminescence microscopy based on STM, in which tunneling electrons are responsible for the excitation of luminescence (scanning tunneling luminescence or STL). The hot-tunneling-electron excitation is confined to the surface and, consequently, the tunneling luminescence spectrum reveals the electronic states near the surface. The STM is integrated inside the SEM and, therefore, both CL and STL can be measured over the same location and compared. Using this setup, the transition from the grain interior to the surface can be investigated. We have improved the collection of our optics to a level in which tunneling luminescence spectrum imaging can be performed. Here we present a detailed account on our investigation of the surface electronics in CIGS deposited in the regime of selenium deficiency as defined by /( +  + < Ga >) = 1.
Intrinsic Localized Lattice Modes and Thermal Transport: Potential Application in a Thermal Rectifier
Authors: Manley Michael E
Published: June 2009

Recent experiments provide evidence of intrinsic localized modes (ILMs) in the lattice dynamics of conventional 3D materials. Here evidence that ILMs in uranium metal enhance the thermal conductivity is presented along with speculation on how thermal transport by ILMs might be used to improve a reported design for a solid-state thermal rectifier.
Application of Simple Cycloalkylsilanetriols as Surface Modifier for Inorganic Particles
Authors: Yoo Bok Ryul , Jung Dong Euy , Han Joon Soo
Published: June 2009

Simple cycloalkylsilanetriols RSi(OH)3 [R =c- pentyl (1) and c-hexenyl (2b)] were synthesized as white powders in 70% and 90% isolated yields, respectively, from the hydrolysis of the corresponding trialkoxysilanes with mild acidic water. Silanetriols 1,2 are soluble in water and polar organic solvents such as alcohol, acetone, THF, DMSO, and etc. They can be applied as surface modifiers for inorganic materials such as silica and titania through simple two step processes: 1) organosilanetriol interact with hydroxyl groups on inorganic materials through hydrogen bonding to make molecular layered thin coating on the inorganic surface, 2) then can undergo condensation by heating about 110 ℃ above to form M-O-Si covalent bond to give hydrophobic silica. With the treatment of ca. 50 nm spherical silica with 5 wt % alkylsilaneol 1, no precipitation of silica particles in water was observed, indicating good surface modifiers for silica particle. In this presentation we will discuss the application of silanetriols as surface modifier for inorganic materials such as silica and titania particles.
Experimental Evidence of the Hyperfine Interaction between Hole and Nuclear Spins in InAs/GaAs Quantum Dots
Authors: Eble Benoit , Testelin Christophe , Desfonds Pascal , Bernardot Frederic , Balocchi Andrea , Amand Thierry , Miard Anne , Lemaître Aristide , Marie Xavier , Chamarro Maria
Published: June 2009

The spin dynamics of resident holes in singly p-doped InAs/GaAs quantum dots is studied by pump-probe photo-induced circular dichroism experiments. We show that the hole spin dephasing is controlled by the hyperfine interaction between the hole spin and nuclear spins. We find a characteristic hole spin dephasing time of 12 ns, in close agreement with our calculations based on a dipole-dipole coupling between the hole and the quantum dot nuclei. Finally we demonstrate that a small external magnetic field, typically 10 mT, quenches the hyperfine hole spin dephasing.
Topological Interlocking in Design of Structures and Materials
Authors: Estrin Yuri , Dyskin Arcady , Pasternak Elena , Schaare Stephan
Published: June 2009

Since its introduction in 2001 [1], the concept of topological interlocking has advanced to reasonable maturity, and various research groups have now adopted it as a promising avenue for developing novel structures and materials with unusual mechanical properties. In this paper, we review the known geometries of building blocks and their arrangements that permit topological interlocking. Their properties relating to stiffness, fracture resistance and damping are discussed on the basis of experimental evidence and modeling results. An outlook to prospective engineering applications is also given.
Next Generation Phase Change Materials as Multifunctional Watery Suspension for Heat Transport and Heat Storage
Authors: Hadjieva Milka Markova , Bozukov Metodi , Gutzov Ivan
Published: June 2009

The phase change materials (PCM) are known since years with high thermal storage capacity but with limited applications. The modified PCM mainly paraffin watery suspensions, so called PCM slurry, improve some PCM drawbacks (thermal conductivity) and as paraffin multifunctional fluids can work in both, heat transport and heat storage for cooling technology applications. The structural and thermophysical properties of two types PCM slurry were good basis for comparison of their efficiency: paraffin microcapsule slurry (A) and paraffin emulsion slurry (B), both working in temperature range of phase transition from 2-12 degreesC. The equipments as differential scanning calorimetry (DSC), model NETZSCH DSC 200 PC; scanning electron microscopy (SEM), JOEL model JSM-5510; hot stage optical microscopy, LINKAM model TMS 94 and hand made thermal cycling system operational with Danfoss cooling machine that ensured 2 kW cooling capacity at 40oC; gave accurate results, characterizing completely, from structural and thermal point of view both types of PCM multifunctional structured fluids. Structural stability of the advanced phase change multifunctional fluids was discussed on sample imaging in variable magnifications made by method of Hot Stage microscopy and precise SEM study. Systematization of the DSC results obtained, including temperature range of phase transition and thermal storage capacity, measured before and after repeatable thermal cycling of the PCM multifunctional fluids, allowed selection of the PCM slurry working samples with relatively high thermal capacity applicable to further development in prototypes. Heat absorbed/released, calculated by NETZSCH DSC software, was for PCM slurry A in the range of 80 to 82 kJ/kg, while PCM slurry B showed thermal storage capacity from 56 to 53 kJ/kg. Correlation between the structural properties and thermal storage capacity of the phase change multifunctional fluids led to practical conclusions concerning: homogeneity; crystal growth/conditions; structural compatibility between components; prediction of the heat flow behavior of multifunctional PCM slurries in cooling technology for storage and transport of heat.
Determinação do volume, do fator de forma e da porcentagem de casca de árvores individuais em uma Floresta Ombrófila Aberta na região noroeste de Mato Grosso
Authors: Colpini Chirle , Travagin Danielle Parra , Soares Thelma Shirlen , Moraes e Silva Versides Sebastião
Published: June 2009

O objetivo deste estudo foi testar e selecionar modelos que expressam o volume com e sem casca e determinar o fator de forma e a porcentagem de casca para uma área de floresta ombrófila aberta na região noroeste de Mato Grosso. Foi realizada a cubagem rigorosa de 91 árvores para a obtenção do diâmetro, espessura de casca, altura total do fuste e volume sólido. Dez modelos volumétricos foram testados, sendo que para a seleção do melhor modelo foram usadas as estatísticas do coeficiente de determinação ajustado, erro padrão da estimativa, seguida da análise de resíduos e distribuição gráfica dos resíduos. Os modelos selecionados foram validados pela aplicação do teste L&O. O fator de forma médio obtido foi de 0,7424 e 0,7297 com e sem casca, respectivamente. O volume médio de casca foi de 0,4292 m³ (7,45% do volume total). O modelo de Schumacher-Hall foi o que melhor se ajustou aos dados de volumes com e sem casca.
Sobrevida em cinco anos e fatores prognósticos em mulheres com câncer de mama em Santa Catarina, Brasil
Authors: Schneider Ione Jayce Ceola , d'Orsi Eleonora
Published: June 2009

Este estudo tem o objetivo de descrever a sobrevida em câncer de mama e os fatores associados à mesma. Caracteriza-se como uma coorte histórica de mulheres com diagnóstico de câncer de mama no período de 2000 a 2002, que foram catalogadas nos registros hospitalares de câncer do Centro de Pesquisas Oncológicas de Santa Catarina e Hospital de Caridade - Irmandade Nosso Senhor dos Passos, os dois localizados em Florianópolis, Santa Catarina, Brasil. Para a análise estatística foram utilizados o estimador de Kaplan-Meier e o modelo de Cox. A taxa de sobrevida geral em cinco anos foi de 76,2% (IC95%: 73,6-78,9). Os fatores independentes associados ao maior risco de óbito foram faixa etária menor de 30 anos (hazard ratio- HR = 3,09; IC95%: 1,25-7,67); as mulheres analfabetas (HR = 3,70; IC95%: 1,44-9,55); as com estadiamento III (HR = 5,27; IC95%: 2,56-10,82) e IV (HR = 14,07; IC95%: 6,81-29,06). Mulheres jovens são aquelas com piores taxas de sobrevida. Também existem muitas mulheres sendo diagnosticadas em estádios avançados, tendo uma sobrevida pior, demonstrando a necessidade de ações de diagnóstico precoce.
Início da terapia anti-retroviral em estágio avançado de imunodeficiência entre indivíduos portadores de HIV/AIDS em Belo Horizonte, Minas Gerais, Brasil
Authors: Fernandes José Roberto Maggi , Acurcio Francisco de Assis , Campos Lorenza Nogueira , Guimarães Mark Drew Crosland
Published: June 2009

O objetivo deste trabalho foi verificar a proporção de início tardio da terapia anti-retroviral (TARV) e seus fatores associados. Estudo de corte transversal com pacientes de dois serviços públicos de referência (n = 310) em Belo Horizonte, Minas Gerais, Brasil. Atraso no início da TARV foi definido como ter contagem de linfócitos T CD4+ < 200 células/mm³ ou manifestação clínica de imunodepressão grave. A maioria era do sexo masculino (63,9%) e não possuía plano de saúde (76,1%). A proporção de início tardio da TARV foi 68,4%. Grande parte (75,2%) iniciou TARV < 120 dias após a primeira consulta médica. Estar desempregado, realizar anti-HIV por indicação de profissional de saúde, < 2 consultas no serviço até seis meses antes do início da TARV e tempo entre primeira consulta para o HIV e início da TARV < 120 dias estiveram associados de forma independente com início tardio da TARV. São necessários estudos que avaliem o custo-efetividade da realização do anti-HIV como teste de rastreamento da população geral. Facilitar o acesso dos pacientes com resultado positivo aos serviços de referência pode contribuir para a redução do número de pacientes que iniciam tardiamente a TARV.
Role of the vitamin C in diethylnitrosamine-induced esophageal cancer in Wistar rats
Authors: Ramos Almino Cardoso , Araujo Marina Rachel , Lopes Luiz Roberto , Andreollo Nelson Adami
Published: June 2009

PURPOSE: To evaluate the inhibitory effect of vitamin C on the experimental esophageal carcinogenesis induced by diethylnitrosamine (NDEA). METHODS: Sixty Wistar male rats aged three months, with mean weight of 210 g were employed in the study and were divided into four different groups according to the drinking drugs: group I - controls: only water, seven days a week; group II - only vitamin C, seven days a week; group III - NDEA, three days a week and water during the other four days; group IV - NDEA, three days a week and vitamin C during the other four days; group V - NDEA together with vitamin C three days a week, and only water during the other four days and group VI - NDEA together with vitamin C three days a week and vitamin C during the other four days. The dosages of NDEA were: - 10 mg. / Kg / day and vitamin C - 200 mg / animal / day, dissolved in drinking water. The animals were observed during 180 days and after that each one was sacrificed and its esophagus and the stomach were removed together and macro and microscopically analyzed to identify any tumors. RESULTS: The largest number of tumors was observed in the group III: 48 macroscopic lesions (4.8 lesions per animal) and 23 microscopic lesions (2.3 lesions per animal). The groups that received vitamin C (groups IV, V and VI) showed smaller number of tumors: group V - 0.5 macroscopic lesions and 0.3 microscopic lesions per animal and group VI - 0.1 macroscopic lesions and 0.1 microscopic lesions per animal. The incidence of tumors in the groups V and VI showed statistical significance (p<0.05), when compared to the other groups. CONCLUSION: The vitamin C administered together with diethylnitrosamine showed an inhibitory effect on the experimental esophageal carcinogenesis in Wistar rats.
Chemoprevention by celecoxib in reflux-induced gastric adenocarcinoma in Wistar rats that underwent gastrojejunostomy
Authors: Rocha Frederico Theobaldo Ramos , Lourenço Laercio Gomes , Jucá Mário Jorge , Costa Valéria , Leal Antenor Teixeira
Published: June 2009

PURPOSE: To evaluate chemoprevention by celecoxib in cases of reflux-induced gastric adenocarcinoma, in Wistar rats that underwent gastrojejunostomy. METHODS: Sixty male Wistar rats of average age three months underwent surgery and were distributed into three groups: group 1, exploratory laparotomy; group 2, gastrojejunostomy; and group 3, gastrojejunostomy and daily celecoxib administration. After 53 weeks, the animals were sacrificed. Changes in the mucosa of the gastric body of group 1 and in the gastrojejunal anastomosis of groups 2 and 3, observed in histopathological and immunohistochemical examinations, were compared. All statistical analyses were performed using Epi-Info®, version 3.4.3. RESULTS: Comparison between groups 2 and 3 relative to the presence of adenocarcinoma showed a statistically significant difference (p=0.0023). Analysis of the association between groups 2 and 3 relative to COX-2 expression also showed a statistically significant difference (p=0.0018). CONCLUSION: Celecoxib had an inhibiting effect on gastric carcinogenesis induced by enterogastric reflux in an animal model.
Effect of titanium surface roughness on human bone marrow cell proliferation and differentiation: an experimental study
Authors: Silva Taís Somacal Novaes , Machado Denise Cantarelli , Viezzer Christian , Silva Júnior Aurelício Novaes , Oliveira Marília Gerhardt de
Published: June 2009

PURPOSE: To assess the proliferation and differentiation of human bone marrow-derived cells cultured on titanium surfaces with different roughness characteristics. METHODS: Cells obtained from the iliac crest of an adult human donor were routinely processed and cultured on titanium surfaces of varying roughness, according to their preparation method: polishing only (smooth surface) and polishing followed by etching with HF/HNO3 for 15 and 30 minutes (rough surfaces). Surfaces were assessed using scanning electronic microscopy and profilometry. RESULTS: Titanium disks etched with acid for 15 minutes allowed greater cell proliferation in all culture periods. The level of osteopontin and osteocalcin expression was increased in both acid-etched groups, which indicates an advanced stage of differentiation of cells into osteoblasts. CONCLUSIONS: Increased surface roughness accelerates the differentiation of undifferentiated mesenchymal cells into osteogenic lineage cells, but does not necessarily favor cell proliferation. An intermediate surface roughness of 0.5µm (acid etching for 15 minutes) favors both initial and final cell responses.
Simplified correction of a meningomyelocele-like defect in the ovine fetus
Authors: Abou-Jamra Rogério Chaccur , Valente Paulo Roberto , Araújo Andrezza , Oliveira Rita de Cássia Sanchez e , Saldiva Paulo Hilário , Pedreira Denise Araújo Lapa
Published: June 2009

PURPOSE: To develop a simplified technique for antenatal correction of a meningomyelocele -like defect in fetal sheep to allow direct skin closure. METHODS: A spinal defect was surgically created at 75 days of gestation in the fetuses of 36 pregnant sheep, 23 survived the surgery. At 102 days gestation, the defect was corrected in 14 cases (9 were left untreated). Skin surrounding the defect was dissected below the dermis to permit its edges to be approximated and sutured, without interposing any material to its edges. An interface material intended to protect the neural tissue from skin adhesion was used and the skin defect was completely closed over it. Pregnancy was allowed to continue up to 138 days gestation, the fetuses were submitted to macroscopic and microscopic analysis. RESULTS: The defect was successfully corrected in 90.9% in the experimental group, and spontaneous closure occurred in 22.3% in the control group (p < 0.05). The survival rate after the creation and correction of the defect was 63.4% and 78% respectively. CONCLUSION: This simplified technique was successful in the correction a meningomyelocele-like defect, in the fetal sheep.