bluuebunny/crossref_metadata_2025 huggingface dataset:
Small micromeres contribute to the germline in the sea urchin
Authors: Yajima Mamiko , Wessel Gary M.
Published: December 2010

Many indirect developing animals create specialized multipotent cells in early development to construct the adult body and perhaps to hold the fate of the primordial germ cells. In sea urchin embryos, small micromeres formed at the fifth division appear to be such multipotent cells: they are relatively quiescent in embryos, but contribute significantly to the coelomic sacs of the larvae, from which the major tissues of the adult rudiment are derived. These cells appear to be regulated by a conserved gene set that includes the classic germline lineage genes vasa, nanos and piwi. In vivo lineage mapping of the cells awaits genetic manipulation of the lineage, but previous research has demonstrated that the germline is not specified at the fourth division because animals are fertile even when micromeres, the parent blastomeres of small micromeres, are deleted. Here, we have deleted small micromeres at the fifth division and have raised the resultant larvae to maturity. These embryos developed normally and did not overexpress Vasa, as did embryos from a micromere deletion, implying the compensatory gene regulatory network was not activated in small micromere-deleted embryos. Adults from control and micromere-deleted embryos developed gonads and visible gametes, whereas small micromere-deleted animals formed small gonads that lacked gametes. Quantitative PCR results indicate that small micromere-deleted animals produce background levels of germ cell products, but not specifically eggs or sperm. These results suggest that germline specification depends on the small micromeres, either directly as lineage products, or indirectly by signaling mechanisms emanating from the small micromeres or their descendants.
Dishevelled-associated activator of morphogenesis 1 (Daam1) is required for heart morphogenesis
Authors: Li Deqiang , Hallett Mark A. , Zhu Wuqiang , Rubart Michael , Liu Ying , Yang Zhenyun , Chen Hanying , Haneline Laura S. , Chan Rebecca J. , Schwartz Robert J. , Field Loren J. , Atkinson Simon J. , Shou Weinian
Published: December 2010

Dishevelled-associated activator of morphogenesis 1 (Daam1), a member of the formin protein family, plays an important role in regulating the actin cytoskeleton via mediation of linear actin assembly. Previous functional studies of Daam1 in lower species suggest its essential role in Drosophila trachea formation and Xenopus gastrulation. However, its in vivo physiological function in mammalian systems is largely unknown. We have generated Daam1-deficient mice via gene-trap technology and found that Daam1 is highly expressed in developing murine organs, including the heart. Daam1-deficient mice exhibit embryonic and neonatal lethality and suffer multiple cardiac defects, including ventricular noncompaction, double outlet right ventricles and ventricular septal defects. In vivo genetic rescue experiments further confirm that the lethality of Daam1-deficient mice results from the inherent cardiac abnormalities. In-depth analyses have revealed that Daam1 is important for regulating filamentous actin assembly and organization, and consequently for cytoskeletal function in cardiomyocytes, which contributes to proper heart morphogenesis. Daam1 is also found to be important for proper cytoskeletal architecture and functionalities in embryonic fibroblasts. Biochemical analyses indicate that Daam1 does not regulate cytoskeletal organization through RhoA, Rac1 or Cdc42. Our study highlights a crucial role for Daam1 in regulating the actin cytoskeleton and tissue morphogenesis.
Bcl-2 proteins and autophagy regulate mitochondrial dynamics during programmed cell death in theDrosophilaovary
Authors: Tanner Elizabeth A. , Blute Todd A. , Brachmann Carrie Baker , McCall Kimberly
Published: December 2010

The Bcl-2 family has been shown to regulate mitochondrial dynamics during cell death in mammals and C. elegans, but evidence for this in Drosophila has been elusive. Here, we investigate the regulation of mitochondrial dynamics during germline cell death in the Drosophila melanogaster ovary. We find that mitochondria undergo a series of events during the progression of cell death, with remodeling, cluster formation and uptake of clusters by somatic follicle cells. These mitochondrial dynamics are dependent on caspases, the Bcl-2 family, the mitochondrial fission and fusion machinery, and the autophagy machinery. Furthermore, Bcl-2 family mutants show a striking defect in cell death in the ovary. These data indicate that a mitochondrial pathway is a major mechanism for activation of cell death in Drosophila oogenesis.
Aquaporin 0 enhances gap junction coupling via its cell adhesion function and interaction with connexin 50
Authors: Liu Jialu , Xu Ji , Gu Sumin , Nicholson Bruce J. , Jiang Jean X.
Published: December 2010

Both connexin 50 (Cx50) and aquaporin 0 (AQP0) have important roles in lens development and homeostasis, and their mutations are associated with human congenital cataracts. We have previously shown that Cx50 directly interacts with AQP0. Here, we demonstrate the importance of the Cx50 intracellular loop (IL) domain in mediating the interaction with AQP0 in the lens in vivo. AQP0 significantly increased (~20–30%) the intercellular coupling and conductance of Cx50 gap junctions. However, this increase was not observed when the IL domain was replaced with those from other lens connexins. The Cx50–AQP0 interaction had no effect on Cx50 hemichannel function. A fusion protein containing three extracellular loop domains of AQP0 efficiently blocked the cell-to-cell adhesion of AQP0 and attenuated the stimulatory effect of AQP0 on Cx50 gap junction conductance. These data suggest that the specific interaction between Cx50 and AQP0 enhances the coupling of Cx50 gap junctions, but not hemichannels, through the cell adhesion function of AQP0. This result establishes a physiological role of AQP0 in the functional regulation of gap junction channels.
PML isoforms I and II participate in PML-dependent restriction of HSV-1 replication
Authors: Cuchet Delphine , Sykes Amanda , Nicolas Armel , Orr Anne , Murray Jill , Sirma Hüseyin , Heeren Joerg , Bartelt Alexander , Everett Roger D.
Published: December 2010

Intrinsic antiviral resistance mediated by constitutively expressed cellular proteins is one arm of defence against virus infection. Promyelocytic leukaemia nuclear bodies (PML-NBs, also known as ND10) contribute to host restriction of herpes simplex virus type 1 (HSV-1) replication via mechanisms that are counteracted by viral regulatory protein ICP0. ND10 assembly is dependent on PML, which comprises several different isoforms, and depletion of all PML isoforms decreases cellular resistance to ICP0-null mutant HSV-1. We report that individual expression of PML isoforms I and II partially reverses the increase in ICP0-null mutant HSV-1 plaque formation that occurs in PML-depleted cells. This activity of PML isoform I is dependent on SUMO modification, its SUMO interaction motif (SIM), and each element of its TRIM domain. Detailed analysis revealed that the punctate foci formed by individual PML isoforms differ subtly from normal ND10 in terms of composition and/or Sp100 modification. Surprisingly, deletion of the SIM motif from PML isoform I resulted in increased colocalisation with other major ND10 components in cells lacking endogenous PML. Our observations suggest that complete functionality of PML is dependent on isoform-specific C-terminal sequences acting in concert.
Effect of Spark Assistance on Autoignition Combustion in a Small Two-Stroke Engine
Authors: Wijesinghe J S , Hong G
Published: December 2010

The local thermal energy of the in-cylinder mixture before combustion is critical to enable autoignition (AI) to occur in a gasoline engine. When the thermal energy is insufficient, AI combustion may become very unstable and misfire may occur. Spark assistance has been proposed as a cost-effective and convenient way to enhance the local thermal energy to reach the level required for AI. It also has the potential to make AI temporally controllable. In the work reported in this paper, spark-assisted AI was experimentally investigated on a 160 cm3 two-stroke engine. The spark assistance and internal exhaust gas recirculation were jointly applied to achieve and control AI. The results showed that, at higher engine loads, the spark timing had a significant effect on AI combustion. The timing of the AI was advanced with advanced spark timing. The peak cylinder pressure and heat release rate increased with advanced spark timing. However, the combustion duration was quite independent of the spark timing. At lower engine loads, the spark assistance significantly reduced the cyclic variation in AI combustion. At a fixed engine operating condition with a light load, the spark assistance was only effective when the spark timing is sufficiently advanced. The advancement of the spark timing required to make the spark assistance effective may vary with the engine load and the air-to-fuel ratio.
Effects of Transition Metal Ion Identity and π-Cation Interactions in Metal—Bis(Peptide) Complexes Containing Phenylalanine
Authors: Utley Brandon , Angel Laurence A.
Published: December 2010

Electrospray ionization–tandem mass spectrometry was used to study the effects of the metal ion identity and π-cation interactions on the dissociation pathways of metal–bis(peptide) complexes, where the metal is either Mn2+, Co2+, Ni2+, Cu2+ or Zn2+; and the peptide is either FGGF, GGGG, GF or GG, where G is glycine and F is phenylalanine. The [(FGGF)(FGGF – H) + M2+]+ and [(GGGG)(GGGG – H) + M2+]+ complexes dissociated by losing one FGGF or GGGG, respectively. Relative binding affinities were measured using the cross-over points, where the parent and product ions were equal in ion abundance and a normalized-collision energy scale. The results indicate the relative binding affinities for FGGF and GGGG follow the same order with respect to the transition metal ion identity: Cu2+ < Ni2+ < Mn2+ ≈ Zn2+ < Co2+ and the π-cation interactions in the FGGF complex have a measureable stabilizing effect. In contrast, the main fragmentation channels of [(GF)(GF – H) + M2+]+ and [(GG)(GG – H) + M2+]+ are loss of CO2 and 2CO2 with the [(GF)(GF – H) + M2+]+ complex also exhibiting cinnamic acid, GF, residual glycine, cinnamate and styrene loss.
Tracking Traces of Transition Metals Present in Concrete Mixtures by Inductively-Coupled Plasma Mass Spectrometry Studies
Authors: Bassioni Ghada , Pillay Avin E. , Kadi Mirella El , Fegali Fadi , Fok Sai Cheong , Stephen Sasi
Published: December 2010

Transition metals can have a significant impact in research related to the dosage optimization of superplasticizers. It is known that the presence of transition metals can influence such doses, and the application of a contemporary instrumental method to obtain the profiles of subsisting transition elements in concrete mixtures would be useful. In this work, inductively-coupled plasma mass spectrometry (ICP-MS) is investigated as a possible tool to track traces of transition metals in concrete mixtures. Depth profiling using ICP-MS on proofed and unproofed concrete shows the presence of Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn at trace intensities in the bulk of the samples under investigation. The study demonstrates that the transition metals present in the concrete sample are largely a part of the cement composition and, to a minor degree, a result of exposure to the seawater after curing. The coated concrete samples have a metal distribution pattern similar to the uncoated samples, but slight differences in intensity bear testimony to the very low levels that originate from the exposure to seawater. While X-ray diffraction fails to detect these traces of metals, ICP-MS is successful in detecting ultra-trace intensities to parts per trillion. This method is not only a useful application to track traces of transition metals in concrete, but also provides information to estimate the pore size distribution in a given sample by very simple means.
Bidentate RNA–magnesium clamps: On the origin of the special role of magnesium in RNA folding
Authors: Petrov Anton S. , Bowman Jessica C. , Harvey Stephen C. , Williams Loren Dean
Published: December 2010

Magnesium plays a special role in RNA function and folding. Although water is magnesium's most common first-shell ligand, the oxyanions of RNA have significant affinity for magnesium. Here we provide a quantum mechanical description of first-shell RNA–magnesium and DNA–magnesium interactions, demonstrating the unique features that characterize the energetics and geometry of magnesium complexes within large folded RNAs. Our work focuses on bidentate chelation of magnesium by RNA or DNA, where multiple phosphate oxyanions enter the first coordination shell of magnesium. These bidentate RNA clamps of magnesium occur frequently in large RNAs. The results here suggest that magnesium, compared to calcium and sodium, has an enhanced ability to form bidentate clamps with RNA. Bidentate RNA–sodium clamps, in particular, are unstable and spontaneously open. Due to magnesium's size and charge density it binds more intimately than other cations to the oxyanions of RNA, so that magnesium clamps are stabilized not only by electrostatic interactions, but also by charge transfer, polarization, and exchange interactions. These nonelectrostatic components of the binding are quite substantial with the high charge and small interatomic distances within the magnesium complexes, but are less pronounced for calcium due to its larger size, and for sodium due to its smaller charge. Additionally, bidentate RNA clamps of magnesium are more stable than those with DNA. The source of the additional stability of RNA complexes is twofold: there is a slightly attenuated energetic penalty for ring closure in the formation of RNA bidentate chelation complexes and elevated electrostatic interactions between the RNA and cations. In sum, it can be seen why sodium and calcium cannot replicate the structures or energetics of RNA–magnesium complexes.
Do the hairpin and VS ribozymes share a common catalytic mechanism based on general acid–base catalysis? A critical assessment of available experimental data
Authors: Wilson Timothy J. , Lilley David M.J.
Published: December 2010

The active centers of the hairpin and VS ribozymes are both generated by the interaction of two internal loops, and both ribozymes use guanine and adenine nucleobases to accelerate cleavage and ligation reactions. The centers are topologically equivalent and the relative positioning of key elements the same. There is good evidence that the cleavage reaction of the VS ribozyme is catalyzed by the guanine (G638) acting as general base and the adenine (A756) as general acid. We now critically evaluate the experimental mechanistic evidence for the hairpin ribozyme. We conclude that all the available data are fully consistent with a major contribution to catalysis by general acid–base catalysis involving the adenine (A38) and guanine (G8). It appears that the two ribozymes are mechanistically equivalent.
Train Schedule Coordination at an Interchange Station Through Agent Negotiation
Authors: Tsang Chi Wai , Ho Tin Kin , Ip Kwan Ho
Published: December 2010

In open railway markets, coordinating train schedules at an interchange station requires negotiation between two independent train-operating companies to resolve their operational conflicts. This paper models the stakeholders as software agents and proposes an agent negotiation model to study their interaction. Three negotiation strategies have been devised to represent the possible objectives of the stakeholders, and they determine the behavior of the stakeholders in proposing offers to other stakeholders. Empirical simulation results confirm that the use of the proposed negotiation strategies lead to outcomes that are consistent with the objectives of the stakeholders.
A New Resource-Constrained Multicommodity Flow Model for Conflict-Free Train Routing and Scheduling
Authors: Caimi G. , Chudak F. , Fuchsberger M. , Laumanns M. , Zenklusen R.
Published: December 2010

This paper addresses the problem of generating conflict-free train schedules on a microscopic model of the railway infrastructure. Conflicts arise if two or more trains are scheduled to block the same track section at the same time. A standard model for this problem is the so-called conflict graph, where each considered train path corresponds to a vertex, and edges represent pairwise conflicts so that a conflict-free schedule corresponds to a maximum independent set. Because the linear programming relaxation of the conflict graph formulation is typically very weak, we develop an alternative model using the sequence of resources that each train path passes, encoded in a resource tree. For each resource, we can efficiently determine the maximal conflict cliques by scanning through the blocking times of all train paths and use these cliques as strong cutting planes in an integer linear programming formulation. We show that the number of maximal conflict cliques is linear in the number of train paths, so the ILP formulation uses much fewer but stronger constraints compared to the conflict graph model. In tests with real-world data from the Swiss Federal Railways, the new Resource Tree Conflict Graph model generates for major stations within seconds, even though the underlying model contains about half a million binary variables. This corresponds to a reduction of the computation time of roughly two orders of magnitude when compared to previous approaches and thus allows us to tackle considerable larger problem instances.
Textgattungen und Musikgattungen beim Mönch von Salzburg und bei Oswald von Wolkenstein
Authors: Wachinger Burghart
Published: December 2010

The Mönch von Salzburg and Oswald von Wolkenstein were deeply rooted in German traditions of song poetry, the Mönch also in the Latin songs of the church, but both were also open for available elements of the more advanced French and Italian musical culture. The following study attempts a survey of typical relations between musical forms, metrical patterns and literary semantics in the monodic and polyphonic songs of both poets.
Differential trapping success for small mammals using pitfall and standard cage traps in a woodland savannah region of southwestern Brazil
Authors: Caceres Nilton C. , Nápoli Rodrigo P. , Hannibal Wellington
Published: December 2010

This study aimed to compare the efficacy of different trapping methodologies for sampling small mammals, consisting of trap type (pitfall, Sherman, and wire traps) and position (ground and understorey) in the Cerrado biome of Brazil. Five fragments of woodland savannah were selected for the study. We captured a total of 364 individuals of 14 species of small mammals. Pitfall traps sampled all 14 species (100%), whereas ground cage traps sampled 8 species (57%), and arboreal traps sampled 5 species (36%). The sampling methodologies gave significantly different results, particularly between pitfall and cage traps, and between ground and arboreal cage traps. However, the comparison between Sherman and wire traps indicated no significant difference, although abundance has been higher for wire cages. Our study confirms the high success rate for pitfall traps now in the Cerrado biome and suggests combinations of trapping methodologies for surveying mammalian diversity.
Accurate Determination of System Compliance and Young’s Modulus for Single Fibers
Authors: Ash J. T. , Cross W. M. , Kellar J. J. , Kjerengtroen L.
Published: December 2010

Single fiber testing was conducted utilizing the ASTM D3379-89e1 standard to measure the Young’s modulus for optical glass fibers. Upon analyzing the experimental data, it was discovered that procedural methods to account for system compliance resulted in a source of uncertainty due to the 12.6 % fiber diameter variability between different fibers tested. As a result, the 86.8 GPa Young’s modulus determined included a significant 43.9 % uncertainty. A new method of data analysis was devised to take into account this fiber diameter variability, which lowered the uncertainty to 7.5 % and provided a Young’s modulus of 61.4 GPa. Comparisons were made with the more recent ASTM C1557-03 standard that gave a similar 61.3 GPa Young’s modulus. A large bias error of 41.6 % exists between the Young’s modulus values determined by the two standard methods. The various analytical methods are discussed along with their estimates of uncertainty, the impact on micro-mechanics, and how to lower this uncertainty further.
Adrenomedullin increases ciliary beat frequency and decreases muscular contraction in the rat oviduct
Authors: Liao S B , Ho J C , Tang F , O W S
Published: December 2010

Our laboratory previously showed that oviduct produced the greatest amount of adrenomedullin (ADM) in the rat female reproductive tract. The aim of this study is to investigate the changes in ADM levels resulting from the contact between the sperm and the oviduct and the possible roles of ADM in ciliary beating and oviductal contractility. Oviducts from Sprague–Dawley rats removed at pre- and post-ovulatory stages were cut open longitudinally and treated with ADM and/or receptor blockers before ciliary beat frequency (CBF) was measured. The effects of sperm on ADM production and CBF in the oviduct were also determined. The contraction of the oviduct after treatment with ADM and receptor antagonists was measured using the organ-bath technique. The results showed that ADM increased the CBF in rat oviduct and this stimulating effect was blocked by the calcitonin-gene-related peptide (CGRP) receptor antagonist, hCGRP8–37. CBF was lower in post-ovulatory than pre-ovulatory oviducts. The presence of sperm in the oviduct increased both the ADM level and CBF. ADM treatment was shown to inhibit the contractility of the oviduct by lowering the basal tone and decreasing the contraction amplitude. The ADM receptor antagonist, hADM22–52, was effective in counteracting the relaxation effect of ADM in the oviduct. All in all, these results indicate that ADM may play a crucial role in transporting the gametes/embryos by regulating ciliary beating and muscular contraction.
Human ZP4 is not sufficient for taxon-specific sperm recognition of the zona pellucida in transgenic mice
Authors: Yauger Belinda , Boggs Nathan A , Dean Jurrien
Published: December 2010

The molecular basis of human fertilization remains enigmatic. Mouse models are often used to study sperm–egg recognition, but the mouse zona pellucida surrounding ovulated eggs contains three proteins (ZP1, ZP2, and ZP3) whereas the human zona contains four (ZP1, ZP2, ZP3, and ZP4). Human sperm are fastidious and recognize human but not mouse eggs. Transgenic mouse lines were established to ascertain whether human ZP4 is the sole determinant of human sperm binding. Human ZP4 expressed in transgenic mice had a molecular mass similar to the range of native protein isoforms and was incorporated into the extracellular zona matrix. Transgenic females were fertile with normal litter sizes. Mouse sperm readily recognized transgenic ovulated eggs, but human sperm did not. We conclude that human ZP4 is not sufficient to support human sperm binding to the zona pellucida in transgenic mice and that other zona proteins may be needed for human gamete recognition.
Excess Weight Loss in First-Born Breastfed Newborns Relates to Maternal Intrapartum Fluid Balance
Authors: Chantry Caroline J. , Nommsen-Rivers Laurie A. , Peerson Janet M. , Cohen Roberta J. , Dewey Kathryn G.
Published: December 2010

OBJECTIVES:

The objectives were to describe weight loss in a multiethnic population of first-born, predominantly breastfed, term infants and to identify potentially modifiable risk factors for excess weight loss (EWL).

METHODS:

Data on prenatal breastfeeding intentions, demographic characteristics, labor and delivery interventions and outcomes, breastfeeding behaviors, formula and pacifier use, onset of lactogenesis, and nipple type and pain were collected prospectively. Logistic regression analyses identified independent predictors of EWL (≥10% of birth weight) by using a preplanned theoretical model.

RESULTS:

EWL occurred for 18% of infants who received no or minimal (≤60 mL total since birth) formula (n = 229), including 19% of exclusively breastfed infants (n = 134) and 16% of infants who received minimal formula (n = 95). In bivariate analyses, EWL was associated (P < .05) with higher maternal age, education, and income levels, hourly intrapartum fluid balance, postpartum edema, delayed lactogenesis (>72 hours), fewer infant stools, and infant birth weight. In multivariate logistic regression analysis, only 2 variables predicted EWL significantly, namely, intrapartum fluid balance (adjusted relative risk for EWL of 3.18 [95% confidence interval [CI]: 1.35–13.29] and 2.80 [95% CI: 1.17–11.68] with net intrapartum fluid balance of >200 and 100–200 mL/hour, respectively, compared with <100 mL/hour) and delayed lactogenesis (adjusted relative risk: 3.35 [95% CI: 1.74–8.10]).

CONCLUSIONS:

EWL was more common in this population than reported previously and was independently related to intrapartum fluid balance. This suggests that intrapartum fluid administration can cause fetal volume expansion and greater fluid loss after birth, although other mechanisms are possible.
Approaches to the Difficult Patient/Parent Encounter
Authors: Breuner Cora Collette , Moreno Megan A.
Published: December 2010

Most pediatricians have experienced uneasy interactions involving patients and/or their parents. The majority of literature on this topic reflects encounters in adult medicine, without providing much information for pediatricians who also face this challenge. Unique to the pediatric approach is the added quotient of the parent/family dynamic. Patients or their parents may have personality disorders or subclinical mental health issues, physicians may be overworked or have a lack of experience, and the health care system may be overburdened, fragmented, and inundated with poor communication. Recognizing the physical or emotional responses triggered by challenging patients/families may allow the provider to effectively partner with, instead of confront, the patient or the family. In this article we review existing literature on this subject and describe possible strategies for the pediatrician to use during a difficult encounter.
Geographic Maldistribution of Primary Care for Children
Authors: Shipman Scott A. , Lan Jia , Chang Chiang-hua , Goodman David C.
Published: December 2010

OBJECTIVES:

This study examines growth in the primary care physician workforce for children and examines the geographic distribution of the workforce.

METHODS:

National data were used to calculate the local per-capita supply of clinically active general pediatricians and family physicians, measured at the level of primary care service areas.

RESULTS:

Between 1996 and 2006, the general pediatrician and family physician workforces expanded by 51% and 35%, respectively, whereas the child population increased by only 9%. The 2006 per-capita supply varied by >600% across local primary care markets. Nearly 15 million children (20% of the US child population) lived in local markets with <710 children per child physician (average of 141 child physicians per 100 000 children), whereas another 15 million lived in areas with >4400 children per child physician (average of 22 child physicians per 100 000 children). In addition, almost 1 million children lived in areas with no local child physician. Nearly all 50 states had evidence of similar extremes of physician maldistribution.

CONCLUSIONS:

Undirected growth of the aggregate child physician workforce has resulted in profound maldistribution of physician resources. Accountability for public funding of physician training should include efforts to develop, to use, and to evaluate policies aimed at reducing disparities in geographic access to primary care physicians for children.
Adverse Events After the Use of Benznidazole in Infants and Children With Chagas Disease
Authors: Altcheh Jaime , Moscatelli Guillermo , Moroni Samanta , Garcia-Bournissen Facundo , Freilij Hector
Published: December 2010

BACKGROUND:

Chagas disease is caused by infection with Trypanosoma cruzi. In adults, treatment with benznidazole is associated with a high incidence of adverse drug reactions (ADRs). However, in infants and children, treatment with benznidazole seems associated with a lower incidence and decreased severity of ADRs, but these effects have not been clearly characterized.

OBJECTIVE:

We aimed to describe ADRs observed in infants and children treated with benznidazole.

PATIENTS AND METHODS:

We conducted a prospective cohort study of infants and children in Argentina with Chagas disease treated with benznidazole.

RESULTS:

A total of 107 infants and children diagnosed with asymptomatic Chagas disease (mean age: 6.9 years) were enrolled in the study. Sixty-two events (in 44 children) were considered benznidazole related. Mean ADR duration was 8.2 days. ADRs were mild (80.6%), moderate (16%), or severe (3.2%). Most (77.3%) ADRs were in children older than 7 years. Skin was the organ with the highest incidence of ADRs (21%), followed by the central nervous system (9%) and the gastrointestinal tract (8.5%). Also, the ADR rate was lower in infants and toddlers compared with older children (18% vs 53%) (P < .001).

CONCLUSIONS:

Treatment with benznidazole was well tolerated in children. Most ADRs were mild and did not require treatment suspension. A strong association was observed between ADR incidence and patient age, and most ADRs occurred in children older than 7 years. We believe that anxiety over potential severe ADRs in children with Chagas disease is not justified and should not be an obstacle to using benznidazole.
Acidentes ocupacionais por exposição a material biológico entre a equipe multiprofissional do atendimento pré-hospitalar
Authors: Oliveira Adriana Cristina , Lopes Aline Cristine Souza , Paiva Maria Henriqueta Rocha Siqueira
Published: December 2010

Estudo transversal, tipo survey, realizado com a equipe multiprofissional de Atendimento Pré-hospitalar (APh) de Belo Horizonte, entre junho e dezembro de 2006. Objetivou-se determinar a incidência dos acidentes ocupacionais por exposição a material biológico, condutas pós-acidente, e fatores demográficos determinantes. Utilizou-se questionário estruturado, análise descritiva, cálculo de incidências e regressão logística. A incidência de acidentes com material biológico foi de 20,6%: 40,8% por pérfuro-cortantes e 49,0% por fluidos corporais; 35,3% entre médicos e 24,0% entre enfermeiros. Condutas pós-acidente: sem avaliação médica, 63,3%; subnotificação, 81,6%; nenhuma conduta, 55,0%; e, sem acompanhamento sorológico, 61,2%. Estiveram associados ao acidente: tempo na instituição (Odds ratio-OR 2,84; Intervalo de confiança-IC 95% 1,22-6,62), lotação na Unidade de Suporte Avançado (OR 4,18; IC 95% 1,64-10,64); interação: tempo na instituição e lotação na Unidade de Suporte Básico (OR 0,27; IC 95% 0,07-1,00). Sugere-se a implantação de protocolos pós-acidentes, visando a sua redução; a subnotificação e o aumento do acompanhamento pós-acidente.
Development of the Belridge Field's Diatomite Reservoirs with Hydraulically Fractured Horizontal Wells: From First Attempts to Current Ultra-Tight Spacing
Authors: Allan Malcolm E. , Gold David K. , Reese Dyke W.
Published: December 2010

The diatomite reservoirs in the Belridge giant oil field in the southern San Joaquin Valley of California provide an ideal location for following the growth in understanding and application of horizontal wells through time. Details are presented that cover geology, drilling, completion, and production from four projects totaling 230 of the field's 246 hydraulically stimulated horizontal wells drilled transverse, longitudinal, and oblique to the azimuth of the preferred natural fracture plane.

The diatomite reservoirs are layered biogenic silica deposited in the Miocene Monterey and Reef Ridge formations. They have continuous vertical oil columns ranging up to 1,300 ft (400 m) along the crest of the anticline. However, the permeability is 0.1 to 10 millidarcies which requires all producers to have multiple sand-propped hydraulic fractures to produce at economic rates. Tight spacing and accurate fracture placement are essential to recovering reserves in this massive reservoir. Normal field development is via closely-spaced vertical producers with vertical water injectors for pressure support. However, when pay zones thin-out on the flanks or become less vertically continuous, horizontal wells become the preferred method of development.

Each of the four projects targeted different areas of the field, and had wells drilled in different geomechanical stress regimes. The largest project has 188 horizontal wells completed with multiple longitudinal hydraulic fractures: after an initial pilot study of four wells, Phase 1 consisted of 75 ft (23 m) spacing between the horizontal sections of the wellbores; Phase 2 evaluated and developed 50 ft (15 m) spacing in a less prospective area; and Phase 3 consisted of infill drilling at 37.5 ft (11.5 m) spacing in the Phase 1 area while at the same time converting every fourth horizontal producer to a water injector.

The unconventional petrophysical properties of the diatomite and the variety of stress regimes allow an almost textbook-like look into knowledge capture plus the utilization of successes and learnings for subsequent projects. From first attempts in 1995 to the current ultra-tight spacing, the learnings from this case study are readily applicable to many other fields, especially to shale reservoirs in resource plays, where tight spacing of the hydraulic fractures and a manufacturing assembly-line approach to development may be needed to get hydrocarbons efficiently out of the matrix.
Pilot Scale Testing of A New Configuration of The Membrane Aerated Biofilm Reactor (MABR) to Treat High‐Strength Industrial Sewage
Authors: Stricker Anne‐Emmanuelle , Lossing Heather , Gibson John H. , Hong Youngseck , Urbanic Jane Challen
Published: December 2010

An alternative design of the membrane aerated biofilm reactor (MABR) was developed to overcome some of the current technical and economical limitations preventing full scale applications of the process. The ZeeLung™ system uses a new dense hollow‐fibre membrane with an unprecedented thin diameter. Two pilot units treating a synthetic high‐strength industrial wastewater (4700 mgCOD/L, 145 mgTKN/L) operated successfully for 16 months. They performed simultaneous COD removal, nitrification and denitrification. The very high specific surface area (810 m2/m3) allowed the surface loading rate to be kept low enough (3.6 gCOD/(m2.d)) to maintain a relatively thin biofilm (200 to 350 µm) and use low‐pressure air (41 kPa) instead of high‐pressure pure oxygen. Intermittent air and liquid mixing at high frequency and low shear were compared: they were equally effective in enhancing substrate transfer, but failed to stabilize biofilm accumulation. Air sparging additionally prevented the acidification of the bulk by stripping CO2.
The Effect of Degree of Recycle on the Nitrifier Growth Rate
Authors: Jimenez Jose , Melcer Henryk , Parker Denny , Bratby John
Published: December 2010

The nitrifier maximum specific growth rate, μA,max, is a critical parameter for the design and performance of nitrifying activated sludge systems. Although many investigations studied μA,max, only a few have dealt with the effect of the reactor configuration on this important kinetic parameter. Bench‐ and full‐scale trials were devised to study the effect of the internal mixed‐liquor recycle (IMLR) on the nitrifier growth rate constant. The nitrifier growth rate constant for an existing activated sludge plant was determined at different operational conditions using the high food‐to‐microorganism ratio (F/M) test and by process model calibration. Overall, the results obtained during this study indicate that high IMLR values have a negative effect on μA,max. Based on the results obtained during this investigation, a 15% decrease in μA,max was observed at an IMLR of 4Q or higher. It is surmised that, at high IMLRs, the reactor behavior shifts from a plug‐flow configuration to a “quasi” complete‐mix configuration, influencing either the species selection in activated sludge population or at least the adaptation of specific species. These results have a tremendous effect on the design of activated sludge processes that incorporate IMLR for denitrification, such as the Bardenpho, Modified Ludzack‐Ettinger (MLE), University of Cape Town (UCT), and Phoredox or anaerobic‐anoxic‐aerobic (A2/O) processes.
Treatment of Distillery Wastewater by the Nano‐Scale Zero‐Valent Iron and the Supported Nano‐Scale Zero‐Valent Iron
Authors: Homhoul Phatkanok , Pengpanich Sitthiphong , Hunsom Mali
Published: December 2010

The treatment of wastewater from the distillery industry was carried out by using nano‐scale‐ and supported nano‐scale zero‐valent iron at a laboratory scale and ambient temperature. Effects of dilution, pH, mixing rate, zero‐valent iron dosage, and amount of support for the zero‐valent iron were investigated. All parameters had a significant effect on the removal efficiency of all investigated pollutants. Increasing the number of dilutions and the nano‐scale zero‐valent iron dosage led to the increase of removal efficiency of pollutants. Higher removal efficiency was achieved in an acidic initial pH of wastewater. The reduction of all pollutants was limited by the kinetics of the pollutant destruction/reduction by nano‐scale zero‐valent iron particles at a mixing rate greater than 170 rpm. At optimum condition, greater than 95, 94, and 64% of color, chemical oxygen demand, and biochemical oxygen demand were removed, respectively, within 6 hours. Additionally, the presence of a support had a significant effect on pollutant removal.
CSR as a Political Arena: The Struggle for a European Framework
Authors: Ungericht Bernhard , Hirt Christian
Published: December 2010

This contribution is a reaction to the striking fact that the political aspect of CSR has remained largely hidden in most of the scientific and practice-oriented management literature. This work intends to illuminate the political dimension of CSR in that the changing stance of the European Commission toward CSR between 2001 and 2006 is analyzed and interpreted as a result of political processes within an “issue arena”. For this case study written documents from the most important actors are used (EU Commission, EU Parliament, the Council, advocacy groups and lobbies for industry and civil society CSR platforms) as well as interviews with high ranking representatives of these institutions (conducted in the spring of 2008).
Policy Agendas, Party Control, and PAC Contributions in the American States
Authors: Kirkland Justin H. , Gray Virginia , Lowery David
Published: December 2010

In this research we hypothesize that aggregate PAC behavior is conditional in nature. PACs in a specific issue sector donate more to a certain political party's candidates the more that political party controls the legislature. However, the more active the legislature is on a specific set of issues the more people/groups/PACs are mobilized in response to the issue. Thus, a conditional relationship emerges where aggregate PAC donations to a political party are a function of party control, agenda activity, and an interaction of the two. We test this conditional theory using data from the Institute on Money in State Politics database on PAC donations to state legislative candidates divided into issue sectors. Our results provide support for our hypotheses that aggregate PAC donations to a political party's candidates are conditional on the level of agenda activity on the issues that concern the PACs.
Growth Alliances: Insights from Egypt
Authors: Abdel-Latif Abla , Schmitz Hubert
Published: December 2010

Recent research has shown that alliances between policy makers and investors can be very effective in enhancing investment and growth. Drawing on the case of Egypt, this paper asks where such growth alliances come from, how they evolve over time, what their key features are, how they work, in what circumstances they do good rather than harm, and whether they can be constructed for policy purposes.
The Impact of Regional Trade Integration on Firm Organization and Strategy: British American Tobacco in the Andean Pact
Authors: Holden Chris , Lee Kelley , Fooks Gary Jonas , Wander Nathaniel
Published: December 2010

Processes of regional trade integration may have an important impact on firms' strategies and forms of organization. This article provides an empirical case study of the impact of regional trade integration in the Andean Pact in the 1990s on the strategies and organization of British American Tobacco (BAT), using internal tobacco industry documents. BAT conducted an integrated strategy by lobbying on tax and tariff rates and intellectual property regulations, whilst simultaneously adapting its market strategies and attempting to modify its internal organization. The company incorporated substantial sales in illicit markets into its strategy, and launched new legal export operations within the region, in part to assert ownership over contested trademarks. It attempted to significantly modify its internal organization by better integrating its national operating companies on a regional basis, but was only partially successful in this due to resistance from its powerful Brazilian subsidiary. Changes in intellectual property rules also intensified competition between BAT and its main competitor, Philip Morris, culminating in a legal dispute between the two firms and leading BAT to develop a more coherent strategy on trademark ownership. These findings raise implications for understanding, and regulating, tobacco industry activities worldwide.
Customs Unions and Special Protection
Authors: Tabakis Chrysostomos
Published: December 2010

This paper investigates the impact of customs unions (CUs) on the ability of countries to multilaterally cooperate within an economic environment characterized by trade-flow volatility. We find that the initiation of CU talks results in an easing of multilateral trade tensions, especially with regard to the employment of special-protection instruments, such as anti-dumping duties or safeguards. However, once the CU agreements come into force, a retreat to a more protectionist trading environment becomes necessary so that multilateral cooperation does not break down. Interestingly, in comparison with the pre-CU world, the utilization of special-protection tools in the post-CU world is more severe for high import volumes, but is less frequent overall. Moreover, normal protection remains low, largely unchanged from the pre-CU era.
Znacaj hirurskog lecenja povreda pankreasa u teskoj abdominalnoj traumi
Authors: Radenkovic Dejan , Bajec Djordje , Gregoric Pavle , Jeremic Vasilije , Bumbasirevic Vesna , Djukic Vladimir , Ivancevic Nenad , Karadzic Borivoje , Pandurovic Milena , Lazic Branko , Doklestic Kristina , Sijacki Ana , Lausevic Zeljko , Ilic Nela , Arsenijevic V. , Karamarkovic Aleksandar
Published: December 2010

In spite of its low incidence, pancreatic injuries hold important place in
abdominal trauma because of diagnostic difficulties, severe potential
complications, therapeutic challenges, and high mortality rates. These
injuries are related with specific morbidity and are very often accompanied
with injuries of other organs. This retrospective study included 31 patients
treated at The Clinic for Emergency Surgery of Clinical Center of Serbia
during the period of 2004-2009 with intraoperativelly confirmed diagnosis of
pancreatic trauma. The most common mechanism of injury was blunt trauma
(83,9%). Among available diagnostic methods, abdominal ultrasound was
characterized with high incidence of false-negative findings (33,3%) while
for CT it was at 16,6%. The type of surgical procedure was related to degree
and severity of injury. Specific complications occurred in 22,6% of patients,
while mortality rate was 25,8%. The creation of unambiguous algorithms for
optimal treatment of patients with pancreatic trauma require multi-centric
prospective studies.
Znacaj laparoskopije u proceni tupe abdominalne traume
Authors: Gregoric Pavle , Bajec Djordje , Radenkovic Dejan , Sijacki Ana , Karamarkovic Aleksandar , Jeremic Vasilije , Ivancevic Nenad , Bumbasirevic Vesna , Pandurovic Milena , Karadzic Borivoje , Ilic Nela , Djukic Vladimir
Published: December 2010

Laparoscopic diagnostics provides fast, reliable, clear, and obvious
information on extent and depth of abdominal organs injury with minimizing
additional trauma to the patient. It is performed without any specific
preparations and, if needed, it may be promptly converted into conventional
laparotomy. Through use of optical equipment with various refraction angles
and through variable patient positioning, laparoscopic technique enables
visualization of whole abdominal cavity. In approximately 20% of cases of
unclear findings, and after other performed diagnostic procedures,
laparoscopy provides definitive diagnosis. Abdominal surgeons are familiar
with this method, making interpretation of the results very fast and reliable
and, what is the most important, this method avoids additional trauma caused
by conventional laparotomy.
Surgical treatment of injuries of the stomach and duodenum in abdominal trauma
Authors: Jeremic Vasilije , Milic Ljiljana , Radenkovic Dejan , Bumbasirevic Vesna , Djukic Vladimir , Gregoric Pavle , Ivancevic Nenad , Jovanovic Bojan , Pandurovic Milena , Sijacki Ana , Karadzic Borivoje , Ilic Nela , Bajec Djordje
Published: December 2010

Injuries of the stomach and duodenum have an important place in abdominal
trauma, even though that the isolated injuries are rare. This kind of
injuries is most commonly associated with injuries of other abdominal
organs1. This retrospective study has been done at the Department of
Emergency Surgery, Clinical Centre of Serbia, during the period from January
2004. until January 2009. The study included 36 patients diagnosed
intraoperatively with the injury of the stomach and duodenum. The most common
mechanism of harming were injuries due to blunt trauma (41.7%), the ones
followed by gunshot wounds (30.5%), and the least were stab injuries (27.8%).
With the majority of patients has been conducted sutures (46.3%) and
serosation (30.6%) of the stomach and duodenum. In 24 (66.7%) patients on
admission have been done ultrasound of the abdomen, in 6 (16.7%) abdominal CT
was done, in 4 (11.1%) peritoneal lavage have been done and the x-ray of the
abdomen was performed in 3 (8 , 3%) patients. Specific complications had 1
(2.8%) patient, while 14 (29.9%) patients have had non-specific
complications. Total mortality has been 33.3%.
Damage control surgery: Our experience
Authors: Lausevic Zeljko , Resanovic Vladimir , Vukovic Goran , Karamarkovic Aleksandar , Radenkovic Dejan , Djukic Vladimir , Bajec Djordje
Published: December 2010

Damage control surgery represents widely implemented technique of treatment
of seriously injured patients all over the world. In medical facilities with
large number of seriously injured patients, type of injuries often imposes
method of damage control surgery as ultimate way in treating such patients.
In Emergency center from 2005-2009. 895 patients had been operated because of
the trauma to the abdomen and thorax. Method of damage control surgery had
been implanted on 41 patients (4.6% of all operated patients). 18 patients
died, and 30 seriously injured patients that hadn?t been treated according to
this method had died in operating room. Likewise, 11 non-trauma patients were
treated according to the principles of damage control surgery because of
uncontrolled bleeding. The greatest challenge today is defining criteria for
choosing right patients for damage control surgery.