bluuebunny/crossref_metadata_2025 huggingface dataset:
The role of traditional healers in tooth extractions in Lekie Division, Cameroon
Authors: Agbor Ashu M , Naidoo Sudeshni , Mbia Awono M
Published: May 2011

Background

The extraction of the teeth by traditional healers in Cameroon is an established cultural practice in the central region of the Cameroon. Traditional healers (TH) use herbs and crude un-sterilized instruments and tools for the tooth extraction procedure. The present study investigates the knowledge and practices of traditional healers regarding tooth extraction and the management of its complications.

Methods

A cross sectional design utilizing semi-structured questionnaires was used to collect the data from traditional healers and their patients.

Results

Sixteen traditional healers (TH) were interviewed. All were male and the majority were between 25-35 years old. The most important reason given for the removal of a tooth was "if it has a hole". All reported using herbs to control bleeding and pain after extractions. Only 20% used gloves between patients when extracting a tooth and just over a third (31.3%) gave post-operative instructions. Eighty seven percent managed complications with herbs and 62.5% reported that they would refer their patients to a dentist whenever there are complications. Only a third (31.3%) was familiar with the basic anatomy of a tooth and more than half (56.3%) reported that tooth extractions are the only treatment for dental problems.

One hundred and fifty patients were interviewed with a mean age of 29 years. More than two thirds were in the 21-30 year age group and just over half were male. Sixty six percent reported that they visited the TH because it is cheap, 93.3% were satisfied with the treatment they received while 95.3% reported said they never had a problem after an extraction.

Conclusions

Tooth extractions using medicinal plants is well established in Lekie division, Cameroon. Infection control during extraction is not the norm. Traditional healers are willing to co-operate with oral health workers in improving the oral health of their patients. Mutual cooperation, collaboration and integrating TH into primary oral health care services need to be increased.
Predicting outcome of rethoracotomy for suspected pericardial tamponade following cardio-thoracic surgery in the intensive care unit
Authors: ten Tusscher Birkitt L , Groeneveld Johan AB , Kamp Otto , Jansen Evert K , Beishuizen Albertus , Girbes Armand RJ
Published: May 2011

Objectives

Pericardial tamponade after cardiac surgery is difficult to diagnose, thereby rendering timing of rethoracotomy hard. We aimed at identifying factors predicting the outcome of surgery for suspected tamponade after cardio-thoracic surgery, in the intensive care unit (ICU).

Methods

Twenty-one consecutive patients undergoing rethoracotomy for suspected pericardial tamponade in the ICU, admitted after primary cardio-thoracic surgery, were identified for this retrospective study. We compared patients with or without a decrease in severe haemodynamic compromise after rethoracotomy, according to the cardiovascular component of the sequential organ failure assessment (SOFA) score.

Results

A favourable haemodynamic response to rethoracotomy was observed in 11 (52%) of patients and characterized by an increase in cardiac output, and less fluid and norepinephrine requirements. Prior to surgery, the absence of treatment by heparin, a minimum cardiac index < 1.0 L/min/m2 and a positive fluid balance (> 4,683 mL) were predictive of a beneficial haemodynamic response. During surgery, the evacuation of clots and > 500 mL of pericardial fluid was associated with a beneficial haemodynamic response. Echocardiographic parameters were of limited help in predicting the postoperative course, even though 9 of 13 pericardial clots found at surgery were detected preoperatively.

Conclusion

Clots and fluids in the pericardial space causing regional tamponade and responding to surgical evacuation after primary cardio-thoracic surgery, are difficult to diagnose preoperatively, by clinical, haemodynamic and even echocardiographic evaluation in the ICU. Only absence of heparin treatment, a large positive fluid balance and low cardiac index predicted a favourable haemodynamic response to rethoracotomy. These data might help in deciding and timing of reinterventions after primary cardio-thoracic surgery.
Systematic quantitative characterization of cellular responses induced by multiple signals
Authors: Al-Shyoukh Ibrahim , Yu Fuqu , Feng Jiaying , Yan Karen , Dubinett Steven , Ho Chih-Ming , Shamma Jeff S , Sun Ren
Published: May 2011

Background

Cells constantly sense many internal and environmental signals and respond through their complex signaling network, leading to particular biological outcomes. However, a systematic characterization and optimization of multi-signal responses remains a pressing challenge to traditional experimental approaches due to the arising complexity associated with the increasing number of signals and their intensities.

Results

We established and validated a data-driven mathematical approach to systematically characterize signal-response relationships. Our results demonstrate how mathematical learning algorithms can enable systematic characterization of multi-signal induced biological activities. The proposed approach enables identification of input combinations that can result in desired biological responses. In retrospect, the results show that, unlike a single drug, a properly chosen combination of drugs can lead to a significant difference in the responses of different cell types, increasing the differential targeting of certain combinations. The successful validation of identified combinations demonstrates the power of this approach. Moreover, the approach enables examining the efficacy of all lower order mixtures of the tested signals. The approach also enables identification of system-level signaling interactions between the applied signals. Many of the signaling interactions identified were consistent with the literature, and other unknown interactions emerged.

Conclusions

This approach can facilitate development of systems biology and optimal drug combination therapies for cancer and other diseases and for understanding key interactions within the cellular network upon treatment with multiple signals.
Transcription variants of SLA-7, a swine non classical MHC class I gene
Authors: Hu Rui , Lemonnier Gaëtan , Bourneuf Emmanuelle , Vincent-Naulleau Silvia , Rogel-Gaillard Claire
Published: June 2011

In pig, very little information is available on the non classical class I (Ib) genes of the Major Histocompatibility Complex (MHC) i.e.SLA-6,-7and-8. Our aim was to focus on the transcription pattern of theSLA-7gene. RT-PCR experiments were carried out withSLA-7specific primers targeting either the full coding sequence (CDS) from exon 1 to the 3 prime untranslated region (3UTR) or a partial CDS from exon 4 to the 3UTR. We show that theSLA-7gene expresses a full length transcript not yet identified that refines annotation of the gene with eight exons instead of seven as initially described from the existing RefSeq RNA. These two RNAs encode molecules that differ in cytoplasmic tail length. In this study, anotherSLA-7transcript variant was characterized, which encodes a protein with a shorter alpha 3 domain, as a consequence of a splicing site within exon 4. Surprisingly, a cryptic non canonical GA-AG splicing site is used to generate this transcript variant. An additionalSLA-7variant was also identified in the 3UTR with a splicing site occurring 31 nucleotides downstream to the stop codon. In conclusion, the pigSLA-7MHC class Ib gene presents a complex transcription pattern with two transcripts encoding various molecules and transcripts that do not alter the CDS and may be subject to post-transcriptional regulation.
Gene expression pattern in swine neutrophils after lipopolysaccharide exposure: a time course comparison
Authors: Sanz-Santos Gema , Jiménez-Marín Ángeles , Bautista Rocío , Fernández Noé , Claros Gonzalo M , Garrido Juan J
Published: June 2011

Background

Experimental exposure of swine neutrophils to bacterial lipopolysaccharide (LPS) represents a model to study the innate immune response during bacterial infection. Neutrophils can effectively limit the infection by secreting lipid mediators, antimicrobial molecules and a combination of reactive oxygen species (ROS) without new synthesis of proteins. However, it is known that neutrophils can modify the gene expression after LPS exposure. We performed microarray gene expression analysis in order to elucidate the less known transcriptional response of neutrophils during infection.

Methods

Blood samples were collected from four healthy Iberian pigs and neutrophils were isolated and incubated during 6, 9 and 18 hrs in presence or absence of lipopolysaccharide (LPS) fromSalmonella entericaserovar Typhimurium. RNA was isolated and hybridized to Affymetrix Porcine GeneChip®. Microarray data were normalized using Robust Microarray Analysis (RMA) and then, differential expression was obtained by an analysis of variance (ANOVA).

Results

ANOVA data analysis showed that the number of differentially expressed genes (DEG) after LPS treatment vary with time. The highest transcriptional response occurred at 9 hr post LPS stimulation with 1494 DEG whereas at 6 and 18 hr showed 125 and 108 DEG, respectively. Three different gene expression tendencies were observed: genes in cluster 1 showed a tendency toward up-regulation; cluster 2 genes showing a tendency for down-regulation at 9 hr; and cluster 3 genes were up-regulated at 9 hr post LPS stimulation. Ingenuity Pathway Analysis revealed a delay of neutrophil apoptosis at 9 hr. Many genes controlling biological functions were altered with time including those controlling metabolism and cell organization, ubiquitination, adhesion, movement or inflammatory response.

Conclusions

LPS stimulation alters the transcriptional pattern in neutrophils and the present results show that the robust transcriptional potential of neutrophils under infection conditions, indicating that active regulation of gene expression plays a major role in the neutrophil-mediated- innate immune response.
Genomic study of the response of chicken to highly pathogenic avian influenza virus
Authors: Sironi Laura , Williams John L , Stella Alessandra , Minozzi Giulietta , Moreno Ana , Ramelli Paola , Han Jianlin , Weigend Steffen , Wan Junxing , Lombardi Guerino , Cordioli Paolo , Mariani Paola
Published: June 2011

Background

The host mounts an immune response to pathogens, but few data are currently available on the role of host genetics in variation in response to avian influenza (AI). The study presented here investigated the role of the host genetic background in response to in vivo infection with AI virus (AIV).

Methods

Experimental lines of chicken and commercial crosses were experimentally infected intratracheally with 103 EID50/bird of A/Chicken/Italy/13474/99 H7N1 highly pathogenic avian influenza virus (HPAIV). Chickens were genotyped for the Mx polymorphism causing the S631N mutation, and for the Major Histocompatibility Complex (MHC). Whole-genome genotyping was carried out using 60 k Single Nucleotide Polymorphism (SNP) array developed by the poultry Genome-Wide Marker-Assisted Selection Consortium (GWMASC).

Results

Variability in response of different chicken lines to the HPAIV infections and some degree of resistance to AI were observed: a statistically significant effect of chicken line on the response to infection was found. There was no association between survival in healthy conditions and polymorphisms at the Mx gene and the MHC-B region. The analysis based on the 60 k SNPs provided a good clustering of the chicken lines, but no specific genetic cluster associated with response to AIV was identified.

Conclusions

Neither the genotype at the Mx gene or MHC-B locus, nor for SNP spanning the whole-genome identified loci involved in variations to response to AIV infection. These results point towards the possibility that either the genetic factors affecting the response of chickens to the H7N1 HPAIV are weak, or relevant alleles were not segregating in the studied populations.
Toll-Like Receptor 6 differential expression in two pig genetic groups vaccinated against Mycoplasma hyopneumoniae
Authors: Régia Silva Sousa Katiene , Mauric Frossard Ribeiro André , Roberto Nunes Goes Paulo , Eliza Facioni Guimarães Simone , Lopes Paulo Sávio , Veroneze Renata , Gasparino Eliane
Published: June 2011

Background

Mycoplasma hyopneumoniae is the etiologic agent of enzootic pneumonia, which causes important economic losses to swine industry. The Toll-like receptors (TLRs) are pattern-recognition receptors which detect microbial presence and initiate the innate as well as the adaptative immune defense. Toll-like receptor 6 is a type I transmembrane protein that recognizes bacterial components. The aim of this study was to compare mRNA expression pattern of TLR6 gene in two genetically distinct groups of pigs vaccinated against Mycoplasma hyopneumoniae.

Methods

For each genetic group, peripheral blood was collected just before and 10 days after vaccination from 10 Naturalized Brazilian Piau breed and 10 Commercial White Line serum-negative female piglets. RNA was extracted from peripheral blood mononuclear cells (PBMCs), reverse transcripted and the qRT-PCR performed using SYBR green fluorescence system, using GAPDH gene as endogenous control. Analyses were performed by UNIVARIATE (Shapiro-Wilk test) and MIXED procedures of SAS software (version 9.0).

Results

It was observed significant interaction between breed and vaccination, being the TLR6 mRNA expression higher in the Commercial White line than in the Piau breed after vaccination. Furthermore, there was differential expression before and after vaccination in the Commercial White line.

Conclusions

Analysis of in TLR6 gene expression showed difference between the two distinct genetic groups, however, other TLRs gene expression must be evaluated for a better understanding of innate resistance in the pig concerning Mycoplasma hyopneumoniae infection.
Aiming for the complete utilization of sugar-beet pulp: Examination of the effects of mild acid and hydrothermal pretreatment followed by enzymatic digestion
Authors: Kühnel Stefan , Schols Henk A , Gruppen Harry
Published: May 2011

Background

Biomass use for the production of bioethanol or platform chemicals requires efficient breakdown of biomass to fermentable monosaccharides. Lignocellulosic feedstocks often require physicochemical pretreatment before enzymatic hydrolysis can begin. The optimal pretreatment can be different for different feedstocks, and should not lead to biomass destruction or formation of toxic products.

Methods

We examined the influence of six mild sulfuric acid or water pretreatments at different temperatures on the enzymatic degradability of sugar-beet pulp (SBP).

Results

We found that optimal pretreatment at 140°C of 15 minutes in water was able to solubilize 60% w/w of the total carbohydrates present, mainly pectins. More severe treatments led to the destruction of the solubilized sugars, and the subsequent production of the sugar-degradation products furfural, hydroxymethylfurfural, acetic acid and formic acid. The pretreated samples were successfully degraded enzymatically with an experimental cellulase preparation.

Conclusions

In this study, we found that pretreatment of SBP greatly facilitated the subsequent enzymatic degradation within economically feasible time ranges and enzyme levels. In addition, pretreatment of SBP can be useful to fractionate functional ingredients such as arabinans and pectins from cellulose. We found that the optimal combined severity factor to enhance the enzymatic degradation of SBP was between log R'0 = -2.0 and log R'0 = -1.5. The optimal pretreatment and enzyme treatment solubilized up to 80% of all sugars present in the SBP, including ≥90% of the cellulose.
Promising cytotoxic activity profile of fermented wheat germ extract (Avemar®) in human cancer cell lines
Authors: Mueller Thomas , Jordan Karin , Voigt Wieland
Published: May 2011

Fermented wheat germ extract (FWGE) is currently used as nutrition supplement for cancer patients. Limited recent data suggest antiproliferative, antimetastatic and immunological effects which were at least in part exerted by two quinones, 2-methoxy benzoquinone and 2,6-dimethoxybenzquinone as ingredients of FWGE. These activity data prompted us to further evaluate the in vitro antiproliferative activity of FWGE alone or in combination with the commonly used cytotoxic drugs 5-FU, oxaliplatin or irinotecan in a broad spectrum of human tumor cell lines. We used the sulforhodamine B assay to determine dose response relationships and IC50-values were calculated using the Hill equation. Drug interaction of simultaneous and sequential drug exposure was estimated using the model of Drewinko and potential clinical activity was assessed by the model of relative antitumor activity (RAA). Apoptosis was detected by DNA gel electrophoresis.

FWGE induced apoptosis and exerted significant antitumor activity in a broad spectrum of 32 human cancer cell lines. The highest activity was found in neuroblastoma cell lines with an average IC50 of 0.042 mg/ml. Furthermore, IC50-range was very narrow ranging from 0.3 mg/ml to 0.54 mg/ml in 8 colon cancer cell lines. At combination experiments in colon cancer cell lines when FWGE was simultaneously applied with either 5-FU, oxaliplatin or irinotecan we observed additive to synergistic drug interaction, particularly for 5-FU. At sequential drug exposure with 5-FU and FWGE the observed synergism was abolished.

Taken together, FWGE exerts significant antitumor activity in our tumor model. Simultaneous drug exposure with FWGE and 5-FU, oxaliplatin or irinotecan yielded in additive to synergistic drug interaction. However, sequential drug exposure of 5-FU and FWGE in colon cancer cell lines appeared to be schedule-dependent (5-FU may precede FWGE).

Further evaluation of FWGE as a candidate for clinical combination drug regimens appeared to be warranted.
An upper limit for macromolecular crowding effects
Authors: Miklos Andrew C , Li Conggang , Sorrell Courtney D , Lyon L Andrew , Pielak Gary J
Published: May 2011

Background

Solutions containing high macromolecule concentrations are predicted to affect a number of protein properties compared to those properties in dilute solution. In cells, these macromolecular crowders have a large range of sizes and can occupy 30% or more of the available volume. We chose to study the stability and ps-ns internal dynamics of a globular protein whose radius is ~2 nm when crowded by a synthetic microgel composed of poly(N-isopropylacrylamide-co-acrylic acid) with particle radii of ~300 nm.

Results

Our studies revealed no change in protein rotational or ps-ns backbone dynamics and only mild (~0.5 kcal/mol at 37°C, pH 5.4) stabilization at a volume occupancy of 70%, which approaches the occupancy of closely packing spheres. The lack of change in rotational dynamics indicates the absence of strong crowder-protein interactions.

Conclusions

Our observations are explained by the large size discrepancy between the protein and crowders and by the internal structure of the microgels, which provide interstitial spaces and internal pores where the protein can exist in a dilute solution-like environment. In summary, microgels that interact weakly with proteins do not strongly influence protein dynamics or stability because these large microgels constitute an upper size limit on crowding effects.
Development of butanol-tolerant Bacillus subtilis strain GRSW2-B1 as a potential bioproduction host
Authors: Kataoka Naoya , Tajima Takahisa , Kato Junichi , Rachadech Wanitcha , Vangnai Alisa S
Published: May 2011

As alternative microbial hosts for butanol production with organic-solvent tolerant trait are in high demands, a butanol-tolerant bacterium, Bacillus subtilis GRSW2-B1, was thus isolated. Its tolerance covered a range of organic solvents at high concentration (5%v/v), with remarkable tolerance in particular to butanol and alcohol groups. It was susceptible for butanol acclimatization, which resulted in significant tolerance improvement. It has versatility for application in a variety of fermentation process because it has superior tolerance when cells were exposed to butanol either as high-density, late-exponential grown cells (up to 5%v/v) or under growing conditions (up to 2.25%v/v). Genetic transformation procedure was optimized, yielding the highest efficiency at 5.17 × 103 colony forming unit (μg DNA)-1. Gene expression could be effectively driven by several promoters with different levels, where as the highest expression was observed with a xylose promoter. The constructed vector was stably maintained in the transformants, in the presence or absence of butanol stress. Adverse effect of efflux-mediated tetracycline resistance determinant (TetL) to bacterial organic-solvent tolerance property was unexpectedly observed and thus discussed. Overall results indicate that B. subtilis GRSW2-B1 has potential to be engineered and further established as a genetic host for bioproduction of butanol.
Cis-regulation of IRF5expression is unable to fully account for systemic lupus erythematosus association: analysis of multiple experiments with lymphoblastoid cell lines
Authors: Alonso-Perez Elisa , Suarez-Gestal Marian , Calaza Manuel , Kwan Tony , Majewski Jacek , Gomez-Reino Juan J , Gonzalez Antonio
Published: May 2011

Introduction

Interferon regulatory factor 5 gene (IRF5) polymorphisms are strongly associated with several diseases, including systemic lupus erythematosus (SLE). The association includes risk and protective components. They could be due to combinations of functional polymorphisms and related to cis-regulation of IRF5 expression, but their mechanisms are still uncertain. We hypothesised that thorough testing of the relationships between IRF5 polymorphisms, expression data from multiple experiments and SLE-associated haplotypes might provide useful new information.

Methods

Expression data from four published microarray hybridisation experiments with lymphoblastoid cell lines (57 to 181 cell lines) were retrieved. Genotypes of 109 IRF5 polymorphisms, including four known functional polymorphisms, were considered. The best linear regression models accounting for the IRF5 expression data were selected by using a forward entry procedure. SLE-associated IRF5 haplotypes were correlated with the expression data and with the best cis-regulatory models.

Results

A large fraction of variability in IRF5 expression was accounted for by linear regression models with IRF5 polymorphisms, but at a different level in each expression data set. Also, the best models from each expression data set were different, although there was overlap between them. The SNP introducing an early polyadenylation signal, rs10954213, was included in the best models for two of the expression data sets and in good models for the other two data sets. The SLE risk haplotype was associated with high IRF5 expression in the four expression data sets. However, there was also a trend towards high IRF5 expression with some protective and neutral haplotypes, and the protective haplotypes were not associated with IRF5 expression. As a consequence, correlation between the cis-regulatory best models and SLE-associated haplotypes, regarding either the risk or protective component, was poor.

Conclusions

Our analysis indicates that although the SLE risk haplotype of IRF5 is associated with high expression of the gene, cis-regulation of IRF5 expression is not enough to fully account for IRF5 association with SLE susceptibility, which indicates the need to identify additional functional changes in this gene.
Infliximab in ankylosing spondylitis: alone or in combination with methotrexate? A pharmacokinetic comparative study
Authors: Mulleman Denis , Lauféron Francine , Wendling Daniel , Ternant David , Ducourau Emilie , Paintaud Gilles , Goupille Philippe
Published: June 2011

Introduction

Methotrexate (MTX) has been shown to modify infliximab pharmacokinetics in rheumatoid arthritis. However, its combination with infliximab in the treatment of ankylosing spondylitis (AS) is not recommended. The objective of this study was to examine the influence of MTX on infliximab exposure in patients with AS.

Methods

Patients with AS patients who had predominantly axial symptoms were randomised to receive infliximab alone (infusions of 5 mg/kg at weeks 0, 2, 6, 12 and 18) or infliximab combined with MTX (10 mg/week). Infliximab concentrations were measured before and 2 hours after each infusion and at 1, 3, 4, 5, 8, 10, 14 and 18 weeks. We estimated individual cumulative area under the concentration versus time curves (AUC) for infliximab concentration between baseline and week 18 (AUC0-18). Clinical and laboratory evaluations were performed at each visit. The Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) score was the primary end point for clinical response.

Results

Twenty-six patients were included (infliximab group: n = 12, infliximab + MTX group: n = 14), and 507 serum samples were available for measurement of infliximab concentration. The two groups did not differ with regard to AUC0-18 or evolution of BASDAI scores and biomarkers of inflammation.

Conclusions

The combination of MTX and infliximab does not increase the exposure to infliximab over infliximab alone in patients with AS.

Trial registration

ClinicalTrials.gov: NCT00507403
Moving pictures of the human microbiome
Authors: Caporaso J Gregory , Lauber Christian L , Costello Elizabeth K , Berg-Lyons Donna , Gonzalez Antonio , Stombaugh Jesse , Knights Dan , Gajer Pawel , Ravel Jacques , Fierer Noah , Gordon Jeffrey I , Knight Rob
Published: May 2011

Background

Understanding the normal temporal variation in the human microbiome is critical to developing treatments for putative microbiome-related afflictions such as obesity, Crohn's disease, inflammatory bowel disease and malnutrition. Sequencing and computational technologies, however, have been a limiting factor in performing dense time series analysis of the human microbiome. Here, we present the largest human microbiota time series analysis to date, covering two individuals at four body sites over 396 timepoints.

Results

We find that despite stable differences between body sites and individuals, there is pronounced variability in an individual's microbiota across months, weeks and even days. Additionally, only a small fraction of the total taxa found within a single body site appear to be present across all time points, suggesting that no core temporal microbiome exists at high abundance (although some microbes may be present but drop below the detection threshold). Many more taxa appear to be persistent but non-permanent community members.

Conclusions

DNA sequencing and computational advances described here provide the ability to go beyond infrequent snapshots of our human-associated microbial ecology to high-resolution assessments of temporal variations over protracted periods, within and between body habitats and individuals. This capacity will allow us to define normal variation and pathologic states, and assess responses to therapeutic interventions.
Editorial: Interfering with B cell immunity
Authors: Harris J E , Marshak-Rothstein A
Published: May 2011

The implications of interferon effects on B-cell responses may impact both antimicrobial and autoimmune disease.
2.5D reverse-time migration
Authors: da Silva Neto Francisco A. , Costa Jessé C. , Schleicher Jörg , Novais Amélia
Published: June 2011

Reverse-time migration (RTM) in 2.5D offers an alternative to improve resolution and amplitude when imaging 2D seismic data. Wave propagation in 2.5D assumes translational invariance of the velocity model. Under this assumption, we implement a finite-difference (FD) modeling algorithm in the mixed time-space/wavenumber domain to simulate the velocity and pressure fields for acoustic wave propagation and apply it in RTM. The 2.5D FD algorithm is truly parallel, allowing an efficient implementation in clusters. Storage and computing time requirements are strongly reduced compared to a full 3D FD simulation of the wave propagation. This feature makes 2.5D RTM much more efficient than 3D RTM, while achieving improved modeling of 3D geometrical spreading and phase properties of the seismic waveform in comparison to 2D RTM. Together with an imaging condition that compensates for uneven illumination and/or the obliquity factor, this allows recover of amplitudes proportional to the earth’s reflectivity. Numerical experiments using synthetic data demonstrate the better resolution and improved amplitude recovery of 2.5D RTM relative to 2D RTM.
From time to depth with CRS attributes
Authors: Baykulov Mikhail , Dümmong Stefan , Gajewski Dirk
Published: June 2011

A processing workflow was introduced for reflection seismic data that is based entirely on common-reflection-surface (CRS) stacking attributes. This workflow comprises the CRS stack, multiple attenuation, velocity model building, prestack data enhancement, trace interpolation, and data regularization. Like other methods, its limitation is the underlying hyperbolic assumption. The CRS workflow provides an alternative processing path in case conventional common midpoint (CMP) processing is unsatisfactory. Particularly for data with poor signal-to-noise ratio and low-fold acquisition, the CRS workflow is advantageous. The data regularization feature and the ability of prestack data enhancement provide quality control in velocity model building and improve prestack depth-migrated images.
A laboratory study of NMR relaxation times in unconsolidated heterogeneous sediments
Authors: Grunewald Elliot , Knight Rosemary
Published: June 2011

Nuclear magnetic resonance (NMR) relaxation-time measurements can provide critical information about the physiochemical properties of water-saturated media and are used often to characterize geologic materials. In unconsolidated sediments, the link between measured relaxation times and pore-scale properties can be complicated when diffusing water molecules couple the relaxation response of heterogeneous regions within a well-connected pore space. Controlled laboratory experiments have allowed us to investigate what factors control the extent of diffusional coupling in unconsolidated sediments and what information is conveyed by the relaxation-time distribution under varied conditions. A range of sediment samples exhibiting heterogeneity in the form of a bimodal mineralogy of quartz and hematite were mixed with varied mineral concentration and grain size. NMR relaxation measurements and geometric analysis of these mixtures demonstrate the importance of two critical length scales controlling the relaxation response: the diffusion length ℓD, describing the distance a water molecule diffuses during the NMR measurement, and the separation length ℓS, describing the scale at which heterogeneity occurs. For the condition of ℓS > ℓD, which prevails for samples with low hematite concentrations and coarser grain size, coupling is weak and the bimodal relaxation-time distribution independently reflects the relaxation properties of the two mineral constituents in the heterogeneous mixtures. For the condition of ℓS < ℓD, which prevails at higher hematite concentrations and finer grain size, the relaxation-time distribution no longer reflects the presence of a bimodal mineralogy but instead conveys a more complex averaging of the heterogeneous relaxation environments. This study has shown the potential extent and influence of diffusional coupling in unconsolidated heterogeneous sediments, and can serve to inform the interpretation of NMR measurements in near-surface environments where unconsolidated sediments are commonly encountered.
Prestack 2D parsimonious Kirchhoff depth migration of elastic seismic data
Authors: Sun Robert , McMechan George A.
Published: June 2011

We have extended prestack parsimonious Kirchhoff depth migration for 2D, two-component, reflected elastic seismic data for a P-wave source recorded at the earth’s surface. First, we separated the P-to-P reflected (PP-) waves and P-to-S converted (PS-) waves in an elastic common-source gather into P-wave and S-wave seismograms. Next, we estimated source-ray parameters (source p values) and receiver-ray parameters (receiver p values) for the peaks and troughs above a threshold amplitude in separated P- and S-wavefields. For each PP and PS reflection, we traced (1) a source ray in the P-velocity model in the direction of the emitted ray angle (determined by the source p value) and (2) a receiver ray in the P- or S-velocity model back in the direction of the emergent PP- or PS-wave ray angle (determined by the PP- or PS-wave receiver p value), respectively. The image-point position was adjusted from the intersection of the source and receiver rays to the point where the sum of the source time and receiver-ray time equaled the two-way traveltime. The orientation of the reflector surface was determined to satisfy Snell’s law at the intersection point. The amplitude of a P-wave (or an S-wave) was distributed over the first Fresnel zone along the reflector surface in the P- (or S-) image. Stacking over all P-images of the PP-wave common-source gathers gave the stacked P-image, and stacking over all S-images of the PS-wave common-source gathers gave the stacked S-image. Synthetic examples showed acceptable migration quality; however, the images were less complete than those produced by scalar reverse-time migration (RTM). The computing time for the 2D examples used was about 1/30 of that for scalar RTM of the same data.
Finite-difference modeling with adaptive variable-length spatial operators
Authors: Liu Yang , Sen Mrinal K.
Published: June 2011

Most finite-difference simulation algorithms use fixed-length spatial operators to compute spatial derivatives. The choice of length is dictated by computing cost, stability, and dispersion criteria that are satisfied globally. We propose finite-difference schemes with adaptive variable-length spatial operators to decrease computing costs significantly without reducing accuracy. These schemes adopt long operators in regions of low velocity and short operators in regions of high velocity. Two methods automatically determine variable operator lengths. Dispersion analysis, along with 1D and 2D modeling, demonstrates the validity and efficiency of our schemes. In addition, a hybrid absorbing boundary condition helps reduce unwanted reflections from model boundaries. Our scheme is more efficient than those based on variable-grid methods for modeling, migration, and inversion of models with complex velocity structures because the latter require local grid refinement, which usually increases memory requirements and computing costs.
Cannabis use before age 15 and subsequent executive
functioning
Authors: Fontes Maria Alice , Bolla Karen I. , Cunha Paulo Jannuzzi , Almeida Priscila Previato , Jungerman Flávia , Laranjeira Ronaldo Ramos , Bressan Rodrigo A. , Lacerda Acioly L. T.
Published: May 2011

Background

Many studies have suggested that adolescence is a period of particular
vulnerability to neurocognitive effects associated with substance misuse.
However, few large studies have measured differences in cognitive
performance between chronic cannabis users who started in early
adolescence (before age 15) with those who started later.

Aims

To examine the executive functioning of individuals who started chronic
cannabis use before age 15 compared with those who started chronic
cannabis use after 15 and controls.

Method

We evaluated the performance of 104 chronic cannabis users (49
early-onset users and 55 late-onset users) and 44 controls who undertook
neuropsychological tasks, with a focus on executive functioning.
Comparisons involving neuropsychological measures were performed using
generalised linear model analysis of variance (ANOVA).

Results

The early-onset group showed significantly poorer performance compared
with the controls and the late-onset group on tasks assessing sustained
attention, impulse control and executive functioning.

Conclusions

Early-onset chronic cannabis users exhibited poorer cognitive performance
than controls and late-onset users in executive functioning. Chronic
cannabis use, when started before age 15, may have more deleterious
effects on neurocognitive functioning.
Age and birth cohort differences in the prevalence of common
mental disorder in England: National Psychiatric Morbidity Surveys
1993–2007
Authors: Spiers Nicola , Bebbington Paul , McManus Sally , Brugha Traolach S. , Jenkins Rachel , Meltzer Howard
Published: May 2011

Background

There are concerns that the prevalence of mental disorder is
increasing.

Aims

To determine whether the prevalence of common adult mental disorders has
increased over time, using age–period–cohort analysis.

Method

The study consisted of a pseudocohort analysis of a sequence of three
cross-sectional surveys of the English household population. The main
outcome was common mental disorder, indicated by a score of 12 or above
on the Revised Clinical Interview Schedule (CIS-R). Secondary outcomes
were neurotic symptoms likely to require treatment, indicated by a CIS-R
score of 18 or over, and individual subscale scores for fatigue, sleep
problems, irritability and worry.

Results

There were 8670 participants in the 1993 survey, 6977 in the 2000 survey
and 6815 in the 2007 survey. In men a significant increase in common
mental disorder occurred between the cohort born in 1943–9 and that born
in 1950–6 (odds ratio 1.4, 95% CI 1.1–1.9) but prevalence in subsequent
cohorts remained largely stable. More extended increases in prevalence of
sleep problems and mental disorders were observed in women, but not
consistently across cohorts or measures.

Conclusions

We found little evidence that the prevalence of common mental disorder is
increasing.
Psychological treatments in intellectual disability: the
challenges of building a good evidence base
Authors: Bhaumik Sabyasachi , Gangadharan Satheesh , Hiremath Avinash , Russell Paul Swamidhas Sudhakar
Published: May 2011

Psychological treatments are widely used for the management of mental health
and behavioural problems in people with intellectual disabilities. The
evidence base, including the cost-effectiveness of such interventions, is
limited. This editorial explores the current evidence base and analyses its
strengths and limitations. The editorial also highlights current problems in
conducting randomised controlled trials in this area and suggests a way
forward.
The truth about genetic variation in the serotonin transporter
gene and response to stress and medication
Authors: McGuffin Peter , Alsabban Shaza , Uher Rudolf
Published: May 2011

The question of whether a functional variant in the promoter of the
serotonin transporter gene (5-HTTLPR) influences response to adversity
and/or antidepressants has generated great interest and controversy. A
review of the literature suggests that the issue is complicated by
differences in methodology and sample ethnicity. When these confounders are
accounted for, there probably is a real, if small, effect of 5-HTTLPR on
response to both serotonin reuptake inhibitors and environmental
adversity.
MAOA, abuse exposure and antisocial behaviour: 30-year
longitudinal study
Authors: Fergusson David M. , Boden Joseph M. , Horwood L. John , Miller Allison L. , Kennedy Martin A.
Published: May 2011

Background

Recent studies have raised issues concerning the replicability of gene ×
environment (G × E) interactions involving the monoamine oxidase A
(MAOA) gene in moderating the associations between
abuse or maltreatment exposure and antisocial behaviour. This study
attempted to replicate the findings in this area using a 30-year
longitudinal study that has strong resemblance to the original research
cohort.

Aims

To test the hypothesis that the presence of the low-activity
MAOA genotype was associated with an increased
response to abuse exposure.

Method

Participants were 398 males from the Christchurch Health and Development
Study who had complete data on: MAOA promoter region
variable number tandem repeat genotype; antisocial behaviour to age 30;
and exposure to childhood sexual and physical abuse.

Results

Regression models were fitted to five antisocial behaviour outcomes
(self-reported property offending; self-reported violent offending;
convictions for property/violent offending; conduct problems; hostility)
observed from age 16 to 30, using measures of childhood exposure to
sexual and physical abuse. The analyses revealed consistent evidence of G
× E interactions, with those having the low-activity
MAOA variant and who were exposed to abuse in
childhood being significantly more likely to report later offending,
conduct problems and hostility. These interactions remained statistically
significant after control for a range of potentially confounding factors.
Findings for convictions data were somewhat weaker.

Conclusions

The present findings add to the evidence suggesting that there is a
stable G × E interaction involving MAOA, abuse exposure
and antisocial behaviour across the life course.
Older psychiatric in-patients' knowledge about psychotropic and non-psychotropic medications
Authors: Perecherla Sri , Macdonald Alastair J. D.
Published: May 2011

Aims and method

We hypothesised that, because of stigma associated with mental illness, patients' knowledge of psychotropic medication would be less than that of non-psychotropic medication. We set out to establish the extent of knowledge about these medications using a cross-sectional survey of in-patients over 65 years of age in south London.

Results

Of the study population (n = 86), 42% demonstrated an understanding of the purpose of taking both psychotropic and non-psychotropic medication, 15% understood only their psychotropic medication, 16% understood only their non-psychotropic medication and 27% understood neither medication. A surprising finding was that more than 20% of these patients with cognitive impairment were not able to recount their legal status; this factor was independently related to whether or not they knew the purpose of their psychotropic medication, and also whether or not they knew the purpose of neither type of medication.

Clinical implications

Poor knowledge of medication has been associated with non-adherence and relapse. Older adults are likely to receive multiple medications because of their increased susceptibility to physical and psychiatric disorders with increasing age, so even more emphasis has to be placed on increasing knowledge of medication.
Violence and aggression at a substance misuse treatment clinic in Ireland
Authors: Iro Chinedu J. , Nkire Nnamdi , O'Connor John
Published: May 2011

Aims and method

To report the rates of violent and aggressive incidents at a drug treatment clinic using a newly introduced incident reporting tool (STARSWeb) and to describe the management strategies currently employed in the management of incidents at the centre. This involved the review of all completed incident reports for the year 2008 and the examination of relevant patient factors.

Results

There were 276 documented incidents at the centre in 2008. The majority of incidents (72.4%) involved verbal abuse and threatening behaviours. Males were responsible for the majority of incidents. Two-thirds of the clients' urine samples were positive for illicit substances at the time of the incidents.

Clinical implications

Violent and aggressive incidents in healthcare settings continue to pose a real challenge to both service providers and service users. An accurate system of reporting of such incidents is indispensable in guiding policy development and management strategies. The STARSWeb system offers a significant improvement in incident reporting towards the attainment of these goals.
Beyond equivalence: prisoners' right to health
Authors: Exworthy Tim , Wilson Simon , Forrester Andrew
Published: May 2011

Prisons have high levels of psychiatric morbidity and function as mental illness recognition centres. Their healthcare wings are not hospitals and timely transfers to hospital are often unavailable. The United Nations' right to the highest attainable standard of health is assessed according to whether healthcare services are available, accessible, acceptable and of good quality (AAAQ). It is proposed that the AAAQ framework goes beyond the principle of equivalence of care and provides a more sophisticated measure for exploring prison healthcare.
A clear step in the right direction
Authors: Anzia Joan M.
Published: May 2011

This is a commentary on the recent online survey by the Royal College of Psychiatrists about case-based discussion as a method of revalidation of psychiatrists in practice in the UK. The overall quality and impact of this pilot study are discussed, as well as some comparisons with revalidation processes in the USA and Canada. Some recommendations for future research are suggested.
Considering single-vendor and multiple-buyers integrated supply chain inventory model with lead time reduction
Authors: Yang M-F , Lo M-C
Published: May 2011

Enterprises within a supply chain can cut their expected inventory costs, raise service level, reduce losses caused by shortages, gain quick-response capability, and improve competitiveness by lead time reduction. However, the extra crashing cost spent within a supply chain partnership will inevitably increase with the shortening of the lead time. On the other hand, the longer the lead time, the larger the amount of safety stock that must be held. The problem of determining a suitable policy of inventory and purchasing management is investigated in this study, with the objective of minimizing total expected inventory costs with multiple partners. This paper presents a single-vendor multiple-buyer integrated inventory model with controllable lead time in which the distribution of lead time demand is normal.
Wood pellet manufacturing improvements through product-driven process value analysis
Authors: Borgianni Y , Cascini G , Rotini F
Published: May 2011

The paper reports an exemplary application in the field of wood pellets production of an original methodology to support business process re-engineering by mapping product requirements to product development phases in order to analyse their contribution to value creation. The methodology has been already published and validated by the authors in different industrial sectors through real case studies, all characterized by well-established business processes, needing improvements to preserve their competitiveness on the marketplace. In this paper the effectiveness of the methodology in identifying process criticalities is tested with regards to industrial processes experiencing under capacities in satisfying the market demand as well as concerning not yet established business ideas. According to this perspective, the wood pellet production process is a suitable case study. In fact, this industrial sector presents high business opportunities in Italy, since the market demand of such kind of energy sources has grown dramatically in the last five years. However, the poor performance of current industrial processes not yet at a mature stage does not allow the complete exploitation of the biomass resources, thus the market demand of woody fuels remains unsatisfied. The paper first positions the work of the authors with respect to already established business process re-engineering techniques; then summarizes the original methodology and details its application in the biofuel field.