bluuebunny/crossref_metadata_2025 huggingface dataset:
Asynchronous stimulus presentation in visual extinction: A psychophysical study
Authors: Geeraerts Sarah , Lafosse Christophe , Vandenbussche Erik , Verfaillie Karl
Published: February 2010

Patients showing visual extinction as a consequence of a unilateral brain lesion can correctly detect a single stimulus in either hemifield but fail to detect the contralesional stimulus (or at least process the stimulus less efficiently) when it is presented simultaneously with an ipsilesional stimulus. In an attempt to uncover the nature of the underlying deficit, some studies have manipulated the temporal characteristics of stimulus presentation. Contra‐ and ipsilesional stimuli with different stimulus onset asynchronies are typically used. In the present study, visual extinction was investigated in a group of left neglect patients (N=10) using a psychophysical paradigm with different stimulus onset asynchronies of target and distractor stimuli presented in different hemifields. Contrast thresholds for a target grating were determined with the target either in isolation or in the presence of an irrelevant distractor grating. When target and distractor gratings were presented simultaneously, neglect patients showed a significant extinction effect, i.e., a significant interference from the right hemifield distractor with left hemifield contrast sensitivity. When the right hemifield distractor preceded the left hemifield target stimulus by 250 ms, two different patterns of results were observed in the neglect patients. Five patients showed a significant improvement compared to the simultaneous presentation condition, five other patients showed a significant increase of the extinction effect. The results suggest that different underlying mechanisms, maybe due to different lesion locations, can cause extinction in neglect patients.
New Meconium Biomarkers of Prenatal Methamphetamine Exposure Increase Identification of Affected Neonates
Authors: Gray Teresa R , Kelly Tamsin , LaGasse Linda L , Smith Lynne M , Derauf Chris , Grant Penny , Shah Rizwan , Arria Amelia , Haning William , Della Grotta Sheri , Strauss Arthur , Lester Barry M , Huestis Marilyn A
Published: February 2010

Background: Prenatal methamphetamine (MAMP) exposure is poorly reflected in neonatal meconium. Often, maternal self-reported MAMP use is not corroborated by positive results in amphetamines immunoassays of meconium, and even if initial test results are positive, they frequently are not confirmed for MAMP or amphetamine (AMP) by chromatographic analysis. The presence of the MAMP metabolites p-hydroxymethamphetamine (pOHMAMP), p-hydroxyamphetamine (pOHAMP), and norephedrine (NOREPH) in meconium may improve the identification of MAMP- and AMP-exposed neonates.

Methods: Immunoassay-positive and -negative meconium samples were subjected to liquid chromatography– tandem mass spectrometric reanalysis for these recently identified metabolites.

Results: pOHAMP and NOREPH were detected only when MAMP and/or AMP were present and thus do not appear to be promising biomarkers of prenatal MAMP exposure. pOHMAMP, in contrast, identified 6 additional neonates whose mothers reported MAMP exposure, yet had a meconium sample screened as negative; pOHMAMP was more likely to be present if maternal MAMP use continued into the third trimester. Although the pOHMAMP results for meconium samples corroborated the maternal self-reports, the confirmation rate for positive meconium screening results did not improve with the inclusion of these new biomarkers.

Conclusions: pOHMAMP identified additional MAMP- exposed neonates; therefore, MAMP, AMP, and pOHMAMP should be included in meconium chromatographic analyses. Maximizing the identification of MAMP-exposed children requires improvement in immunoassay screening tests to reduce false-negative and false-positive results. Additional research will help clarify which AMP-related compounds, if any, contribute to unconfirmed positive results in screening tests. Furthermore, nonamphetamine compounds endogenous to the complex meconium matrix also may cross-react, making chromatographic confirmation of screening results essential.
Association of matrix metalloproteinase 9 genotypes and cardiovascular disease risk factors with serum matrix metalloproteinase 9 concentrations in Taiwanese individuals
Authors: Wu Semon , Hsu Lung-An , Teng Ming-Sheng , Lin Jeng Feng , Chang Hsien-Hsun , Chang Pi-Yueh , Hu Chiao-Feng , Ko Yu-Lin
Published: February 2010

Background: Circulating concentrations of matrix metalloproteinase 9 (MMP-9) are associated with cardiovascular disease mortality in patients with coronary artery disease. We investigated the determinants of MMP-9 concentrations by analyzing MMP-9 genotypes and risk factors for cardiovascular disease.

Methods: A total of 596 individuals were recruited for this study. Six single nucleotide polymorphisms (SNP) with coverage of the MMP-9 gene region were analyzed; and two genotypes, rs3918242-TT and rs2274756-AA, which were in nearly complete linkage disequilibrium, were associated with higher MMP-9 values (p=0.007 and p=0.008, respectively). In age- and gender-adjusted regression models, MMP-9 concentrations were positively associated with the homeostasis model assessment of insulin resistance (HOMA-IR) index and triglyceride concentrations, fasting serum insulin, fasting plasma glucose, C-reactive protein, fibrinogen, and serum amyloid A. By multivariate analysis, rs2274756 genotypes, age, smoking status, fibrinogen and fasting plasma glucose concentrations were all independently associated with MMP-9 (p=0.007, p=0.033, p=0.003, p=0.013, and p=0.012, respectively).

Conclusions: The rs2274756-AA and rs3918242-TT genotypes, younger age, current smoking status and increased fasting plasma glucose, and fibrinogen concentrations were independently associated with high serum MMP-9 concentrations in Taiwanese individuals.

Clin Chem Lab Med 2010;48:543–9.
FOXL2 mutations in Taiwanese patients with blepharophimosis, ptosis, epicanthus inversus syndrome
Authors: Lin Wei-De , Chou I-Ching , Lee Ni-Chung , Wang Chung-Hsing , Hwu Wuh-Liang , Lin Shuan-Pei , Chao Mei-Chyn , Tsai Yushin , Tsai Fuu-Jen
Published: February 2010

Background: Blepharophimosis, ptosis, epicanthus inversus syndrome (BPES) is an autosomal dominant developmental disorder that includes an eyelid malformation associated with (type I) or without (type II) premature ovarian failure (POF). Mutations in the forkhead transcription factor 2 (FOXL2) gene, a member of winged/forkhead transcription factor family, are responsible for both types of BPES. The purpose of this study was to identify mutations in FOXL2 in Taiwanese patients with BPES.

Methods: The karyotype and genomic DNA was prepared from the leukocytes of peripheral venous blood samples. The coding and flanking region sequences of FOXL2 were analyzed by directed or cloning sequencing.

Results: The karyotypes of these patients did not show significant variation, especially on the 3q23 region. Two mutations in FOXL2 were identified in two familial cases. One was c.855-871dup (17-bp insertion) associated with POF. The other was c.384G>A (TGG>TGA), a novel mutation that resulted in non-sense changes of the encoded protein, i.e., p.W128X.

Conclusions: Our results expand the spectrum of FOXL2 mutations and confirm the mutation hotspot in FOXL2 in Taiwanese BPES patients.

Clin Chem Lab Med 2010;48:485–8.
C-reactive protein variants are not associated with susceptibility to stroke and stroke recurrence
Authors: Song Weihua , Yu Hui , Chen Jingzhou , Sun Kai , Hui Rutai
Published: February 2010

Background: C-reactive protein (CRP) has been shown to contribute to the risk of cardiovascular disease. Several single nucleotide polymorphisms (SNPs) at the CRP locus have been found to be associated with CRP concentrations. We hypothesized that genetic variants associated with high CRP may confer a greater risk of stroke and recurrence. The hypothesis was tested in a case-control study and during follow-up of the case population.

Methods: Two genetic variants associated with serum CRP in the CRP gene were genotyped in a Chinese case-control study comprised of 1572 stroke patients and 1485 controls. The case population was followed for a median of 4.5 years (range, 0.1–6.0 years).

Results: During a median 4.5-year follow-up for 1526 stroke patients, 299 recurrent strokes were identified. No association was found between the SNPs or haplotypes of the CRP gene and stroke and its recurrence.

Conclusions: Although these variants and corresponding haplotypes in the CRP gene are associated with serum CRP concentrations, our study does not support that variants and corresponding haplotypes studied here have a major influence on risk of stroke and stroke recurrence. Therefore, we speculate that CRP is not a causal factor for stroke.

Clin Chem Lab Med 2010;48:551–4.
Macro- and micro-mechanical properties of red oak wood (Quercus rubra L.) treated with hemicellulases
Authors: Konnerth Johannes , Eiser Martina , Jäger Andreas , Bader Thomas Karl , Hofstetter Karin , Follrich Jürgen , Ters Thomas , Hansmann Christian , Wimmer Rupert
Published: February 2010

Red oak wood (Quercus rubraL.) samples were submitted to an enzymatic treatment with a commercial mixture of hemicellulases aiming at the selective depolymerization and removal of the hemicelluloses. Mechanical properties of treated samples were characterized and compared with untreated samples at two hierarchical levels. At the macrolevel, tensile properties revealed to be less sensitive to degradation of the cell wall matrix compared to compression and hardness properties. Results obtained through indentation at the microlevel indicated that hardness and the so-called reduced modulus of treated wood were significantly lowered. Accordingly, hardness and reduced elastic modulus have proven to be most sensitive to modification of the cell wall matrix by reducing the content of hemicelluloses. It is proposed that transversal and shear stresses, which are mainly carried by the cell wall matrix, are additional parameters having strong effects on elastic modulus obtained by nanoindentation. Micromechanical modeling was employed to confirm the observed changes. There is consistency between the measured and the modeled properties, obtained at both the microlevel and the macrolevel of wood.
Activities and social interactions in captive Antillean manatees in Mexico
Authors: Hénaut Yann , Becerra Lopez Sylvia P. , Machkour-M'Rabet Salima , Morales-Vela Benjamín , Winterton Peter , Delfour Fabienne
Published: February 2010

Behavioural research in endangered manatees is essential for successful conservation management. We examined the activities and social interactions of a captive group of Antillean manatees located in the Dolphin Discovery Park in Mexico. The group studied was composed of two adults, one subadult and one calf. We determined activity patterns and space use of the manatees in a natural water pool over a daytime period and a night-time period. The behavioural strategies of the manatees included (1) during the day, mainly foraging, feeding, and remaining inactive, and (2) evening activities were divided among social interaction, environment exploration, and resting activities. All the behaviour patterns of the captive manatees seemed to be influenced by the feeding schedule during the day. The number of contacts between manatees increased strongly at night, each individual having a preferred partner for social interaction. The cow-calf dyad showed the highest intensity of contacts, whereas subadults showed the lowest. The relationships observed among individuals reveal a higher social activity than previously described in Antillean manatees.
Cross section measurements of (n, 2n), (n, p) and (n, α) reactions on gadolinium isotopes in the neutron energy range of 13.5 to 14.8 MeV
Authors: Luo Junhua , Liu Rong , Jiang Li , Sun Guihua , Liu Zhenlai , Zhou Fengqun
Published: February 2010

Cross sections for (n, 2n), (n, p), and (n, α) reactions have been measured on gadolinium isotopes at the neutron energies from 13.5 to 14.8 MeV using the activation technique in combination with high-resolution gamma-ray spectroscopy. Neutrons were produced via the 3H(d, n) 4He reaction using solid TiT. The neutron fluences were determined using the monitor reactions 93Nb(n, 2n)92mNb and 27Al(n, α) 24Na. The neutron energy in this measurement was determined by cross section ratios for the 90Zr(n, 2n)89m+gZr and 93Nb(n, 2n)92mNb reactions. Data are reported for the following reactions: 152Gd(n, 2n) 151Gd, 154Gd(n, 2n) 153Gd, 160Gd(n, 2n) 159Gd, 156Gd(n, p) 156Eu, 157Gd(n, p) 157Eu, 158Gd(n, p) 158Eu, and 158Gd(n, α) 155Sm. The cross sections are discussed and compared with the experimental data found in the literature.
Low serum 25-hydroxyvitamin D levels are associated with increased all-cause mortality risk in a general population: the Tromsø study
Authors: Hutchinson Moira Strand , Grimnes Guri , Joakimsen Ragnar Martin , Figenschau Yngve , Jorde Rolf
Published: February 2010

Objective

Ecologic and observational studies have suggested an association between serum 25-hydroxyvitamin D (25(OH)D) levels and cardiovascular disease (CVD) risk factors, CVD mortality, and cancer mortality. Based on this, low serum 25(OH)D levels should be associated with higher all-cause mortality in a general population. This hypothesis was tested in the present study.

Design

The Tromsø study is a longitudinal population-based multipurpose study initiated in 1974 with focus on lifestyle-related diseases. Our data are based on the fourth Tromsø study carried out in 1994–1995.

Methods

Information about death and cause of death was registered by obtaining information from the National Directory of Residents and the Death Cause Registry. Serum 25(OH)D was measured in 7161 participants in the fourth Tromsø study. Results are presented for smokers (n=2410) and non-smokers (n=4751) separately as our immunoassay seems to overestimate 25(OH)D levels for smokers.

Results

During a mean 11.7 years of follow-up, 1359 (19.0%) participants died. In multivariate regression models, there was a significantly increased risk of all-cause mortality (hazard ratio (HR) 1.32, confidence interval (CI) 1.07–1.62) among non-smoking participants in the lowest 25(OH)D quartile when compared with participants in the highest quartile. Equivalent results for smokers were not significant (HR 1.06, CI 0.83–1.35).

Conclusions

Low serum 25(OH)D levels were associated with increased all-cause mortality for non-smokers, but the results did not reach statistical significance for smokers. However, low 25(OH)D levels are known to be associated with impaired general health, and randomized controlled studies are needed to address the question of causality.
Tissue tropism of highly pathogenic avian influenza virus subtype H5N1 in naturally infected mute swans ( Cygnus Olor ), domestic geese ( Anser Anser var. domestica ), pekin ducks ( Anas platyrhynchos ) and mulard ducks ( Cairina moschata × anas platyrhynchos )
Authors: Szeredi Levente , Dán Ádám , Pálmai Nimród , Ursu Krisztina , Bálint Ádám , Szeleczky Zsófia , Ivanics Éva , Erdélyi Károly , Rigó Dóra , Tekes Lajos , Glávits Róbert
Published: February 2010

The 2006 epidemic due to highly pathogenic avian influenza virus (HPAIV) subtype H5N1 in Hungary caused the most severe losses in waterfowl which were, according to the literature at the time, supposed to be the most resistant to this pathogen. The presence of pathological lesions and the amount of viral antigen were quantified by gross pathology, histopathology and immunohistochemistry (IHC) in the organs of four waterfowl species [mute swans (n = 10), domestic geese (n = 6), mulard ducks (n = 6) and Pekin ducks (n = 5)] collected during the epidemic. H5N1 subtype HPAIV was isolated from all birds examined. Quantitative real-time reverse transcriptase-polymerase chain reaction (qRRT-PCR) was also applied on a subset of samples [domestic geese (n = 3), mulard (n = 4) and Pekin duck (n = 4)] in order to compare its sensitivity with IHC. Viral antigen was detected by IHC in all cases. However, the overall presence of viral antigen in tissue samples was quite variable: virus antigen was present in 56/81 (69%) swan, 22/38 (58%) goose, 28/46 (61%) mulard duck and 5/43 (12%) Pekin duck tissue samples. HPAIV subtype H5N1 was detected by qRRT-PCR in all birds examined, in 19/19 (100%) goose, 7/28 (25%) mulard duck and 12/28 (43%) Pekin duck tissue samples. As compared to qRRTPCR, the IHC was less sensitive in geese and Pekin ducks but more sensitive in mulard ducks. The IHC was consistently positive above 4.31 log10 copies/reaction but it gave very variable results below that level. Neurotropism of the isolated virus strains was demonstrated by finding the largest amount of viral antigen and the highest average RNA load in the brain in all four waterfowl species examined.
Envitonmental epidemiological study on respiratory diseases in two Hungarian towns
Authors: Posgay Mária , Varró Mihály János , Szentmihályi Renáta , Lang Zsolt
Published: February 2010

A szerzők korábban beszámoltak egyrészt a Nyergesújfalun, az azbesztcementgyár környezetében, másrészt az iparral jóval kevésbé terhelt Komáromban élő felnőtt lakosság körében végzett, alapvetően légzőszervi, standardizált kérdőíves keresztmetszeti epidemiológiai vizsgálat eredményeiről. Nyergesújfalun (a továbbiakban is: az azbeszttel foglalkozásilag nem exponáltak között) a légzőszervi tünetek, egyéb betegségek és daganatok nem voltak szignifikánsan gyakoribbak az azbesztcementgyár sem 500 m-es, sem 1 km-es körzetén belül az azon kívül élőkhöz viszonyítva, nyers összehasonlítás és logisztikus regressziós modellek szerint. A két várost összehasonlítva megállapítható, hogy krónikus aspecifikus (obstruktív) légzőszervi betegségre (KALB) jellemző tünetek Nyergesújfalun körülbelül másfélszer-két és félszer nagyobb eséllyel fordultak elő (p < 0,001), mint Komáromban. Az ezekkel összefüggő kockázati tényezők közül is több szignifikánsan gyakoribb volt Nyergesújfalun, mint Komáromban. A szerzők ezután a két város logisztikus regressziós modelljeiben alkalmazott korrekciós tényezőket csoportonként összevonták, és az összehasonlítást az összevont korrekciós tényezők alkalmazásával is elvégezték. A legtöbb KALB-tünet esélye ez esetben is szignifikánsan nagyobb volt Nyergesújfalun, mint Komáromban. Mindezekből következik, hogy a környezeti azbesztexpozíció szerepe továbbra sem zárható ki a foglalkozásilag azbeszttel nem exponáltak KALB-tüneteinek kialakulásában. (Megjegyzendő, hogy ez a tanulmány is támogatja a nem, kor, dohányzás, alkoholfogyasztás, elhízás, foglalkozási expozícó, a penészes lakás és az öröklődés etiológiai szerepét a vizsgált végpontok esetében.) Analitikus vizsgálatok igénye felvethető annak tisztázására, hogy mekkora és különbözik-e a két város levegőjében az aktuális azbesztrost-koncentráció (ez utalhat a korábbi koncentrációk alakulására), illetve hogy mekkora és különbözik-e a két városban vett autopsziás tüdőmintákban az akkumulálódott azbesztrost-koncentráció. Főként e kérdések tisztázása esetén átgondolandó, hogy javasolt-e döntéshozói szinten, akár most is, megfelelő intervenció. Ezenfelül, az azonosított egyéb kockázati tényezők eliminálása egészségnevelési lépéseket sürget.
A new ECG marker of anterior acute myocardial infarction
Authors: Tomcsányi János , Nényei Zoltán , Sármán Balázs , Arabadzisz Hrisula , Zsoldos András , Frész Tamás
Published: February 2010

A szerzők az akut anterior myocardialis infarctus egy új EKG-formáját ismertetik. Amíg proximalis LAD-occlusio esetén általában kiterjedt mellsőfali ST-eleváció látható, ezen új formában a hiperakut pozitív T-hullámokat J-pont-süllyedés és aszcendáló ST-depresszió vagy digoxinhatáshoz hasonló sajka-ST-depresszió kíséri. Ezért könnyen elnézhető, ami nagy szívizomvesztéssel járó infarctust vagy akár a beteg halálát is okozhatja. Ezért ezen esetekben a beteget – függetlenül attól, hogy nincs ST-elevációja – mielőbb reperfúziós terépiában kell részesíteni.
Epidemiology of hepatitis C and human immunodeficiency virus infections among injecting drug users in Hungary – what’s next?
Authors: Gyarmathy V. Anna , Rácz József
Published: February 2010

Jelenleg hazánkban az injektáló kábítószer-használók körében a hepatitis C (HCV) előfordulási aránya Budapesten 35% körüli, vidéken pedig 20% alatti, és verifikált emberi immunhiányt okozó vírus (HIV) -fertőzést nem regisztráltak körükben. Matematikai modellek szerint a HCV és a HIV járványtana ebben a kockázati csoportban egybefonódik: amíg a HCV előfordulása körülbelül 35% alatti, a HIV-járvány valószínűsége nagyon csekély, e határ átlépése után viszont egyre terjedő HIV-járványra számíthatunk. E modellek szerint a hazai, főleg a fővárosi, injektáló kábítószer-használók körében egyre nő egy átfogó HIV-járvány valószínűsége. Négy fő módon lehet egy ilyen HIV-járványt késleltetni, illetve minimalizálni: 1. helyettesítő kezelési programokkal; 2. injektáló eszközök legális hozzáférésével; 3. tanácsadással egybekötött, ingyenes, anonim HIV- és HCV-gyorsteszteléssel; és 4. higiénikus injektálási körülmények biztosításával. Az injektáló kábítószer-használók jelenlegi HCV-járványtani helyzete nemcsak mielőbbi széles körű és átfogó megelőzési választ kíván az előrejelzéseken alapuló HIV-járvány elkerülése érdekében, főleg a fővárosban, hanem a járványtani helyzet rendszeres monitorozását is. A megelőzési programok sikeressége két kulcstényezőn múlik: 1. széles körű hozzáférhetőség és 2. folyamatos állami finanszírozás.
Genetic and immunological processes in the pathomechanism of gluten-sensitive enteropathy and associated metabolic bone disorders
Authors: Vereckei Edit , Poór Gyula , Kiss Emese
Published: February 2010

A coeliakia, lisztérzékenység a vékonybél leggyakoribb malabszorpcióhoz vezető immunmediált bélbetegsége, amelyet a gabonafélék gluténfrakciója indít el genetikailag arra hajlamos egyénekben. A gluténexpozíciót követően T-sejt-mediált immunológiai folyamatok indulnak el, amelyek jellemző intestinalis és extraintestinalis tünetekhez vezetnek. Diagnosztikája jelenleg is a jejunalis biopsziára, endomysium és szöveti transzglutaminázellenes antitestek meglétére épül. Genetikai szempontból HLA DQ2/DQ8 asszociáció ismert a bélbetegség hátterében. Gluténmentes étrend szigorú betartása mellett, a klinikai tünetek terén, szövettanilag és szerológiailag is javulás következik be, kedvezően változik a társuló betegségek lefolyása. Az alapbetegség etiopatogenezisében, a genetikai és immunológiai tényezők tekintetében számos új információ vált ismertté az elmúlt években. A társbetegségek körében a mozgásszervi megnyilvánulások közül a csontmetabolikus eltérésekről több, a gyulladásos kórformákkal kapcsolatban kevesebb közlemény jelent meg. Az összefoglaló tanulmány fő célja a genetikai és immunológiai szempontból közös háttér áttekintése az elmúlt évek irodalmi adatainak segítségével.
Psychometric Evaluation of the Stress Scale for Parents with Cleft Lip and/or Palate Children—A Preliminary Study
Authors: Lei Ruoh-Lih , Wang Shiaw-Ling , Cheng Chung-Ping , Chen Philip Kuo-Ting , Chin Chi-Chun
Published: February 2010

Objective

To develop the Stress Scale for Parents With Cleft Lip and/or Palate Children in Taiwan and to evaluate the psychometric properties of the scale with a group of parents who have children with cleft lip and/or palate.

Design

In phase 1, qualitative procedures were conducted in constructing the item pool for the Stress Scale for Parents With Cleft Lip and/or Palate Children. Psychometric properties of the scale were assessed in phase 2.

Setting

Outpatient department of a children's hospital in northern Taiwan.

Participants

Phase 1 included 21 parents of children with cleft lip and/or palate. Phase 2 included 184 parents of children with cleft lip and/or palate.

Interventions

The item pool was developed by interview, content analysis, and literature review. Problematic items were identified by item analysis.

Main Outcome Measures

Exploratory factor analysis was used to examine the construct validity. Reliabilities were evaluated by Cronbach alpha and intraclass correlation coefficients.

Results

Thirty-three items with a content validity index greater than .80 were recognized. They were grouped into four categories by exploratory factor analysis and accounted for 42.34% of the total variance. Internal consistency reliability was high for the total scale (Cronbach a = .90) and ranged from .71 to .84 on the subscales. Test-retest reliability with intraclass correlation coefficient was .94 on the total scale (p < .0001, 95% confidence interval) and from .90 to .96 for the subscales.

Conclusions

The Stress Scale for Parents With Cleft Lip and/or Palate Children appears to be a reliable tool with strong evidence of content and construct validity that may be useful in assessing parental stress in the caretakers of children with cleft lip and/or palate.
Fixed-Dose-Rate Gemcitabine: A Viable First-Line Treatment Option for Advanced Pancreatic and Biliary Tract Cancer
Authors: Milella Michele , Gelibter Alain J. , Pino Maria Simona , Bossone Giandominik , Marolla Paolo , Sperduti Isabella , Cognetti Francesco
Published: February 2010

Background.

We have already reported on fixed-dose-rate gemcitabine (FDR-Gem) in advanced, inoperable pancreatic ductal adenocarcinoma (PDAC) and biliary tract cancer (BTC) in the context of a formal phase II study; building on that experience, we have now expanded the study to reach a cumulative accrual of 106 patients.

Methods.

One hundred six patients (PDAC/BTC, 75/31) were treated with weekly FDR-Gem (1,000 mg/m2 infused at 10 mg/m2 per minute). Patient characteristics included: male-to-female ratio, 0.83; median age, 63 years (range, 28–82); metastatic disease in 66% of patients; and an Eastern Cooperative Oncology Group performance status (ECOG PS) score of 0–1 in 81% of patients.

Results.

The median and total number of treatment weeks delivered were 8 (range, 2–22) and 1,154, respectively. Thirteen percent of patients achieved an objective response, 42% experienced a positive clinical benefit response, and 54% achieved a >50% reduction in serum cancer antigen (CA)19.9 levels. The median progression-free survival (PFS) and overall survival (OS) times for the entire population were 4.4 months (95% confidence interval [CI], 3.5–5.1 months) and 7.7 months (95% CI, 6.3–8.8 months), respectively, with 20% of patients alive at 1 year. On multivariate analysis, a CA19.9 reduction >50% and baseline ECOG PS score of 0 were the only independent predictors of PFS and OS, respectively. Treatment was well tolerated, with grade 3–4 neutropenia in 47 of 1,154 treatment weeks (4.1%), and grade 3 anemia and thrombocytopenia in 8 of 1,154 (0.7%) and 16 of 1,154 (1.4%) treatment weeks, respectively.

Conclusions.

Currently available evidence, including this updated analysis, supports the use of FDR-Gem as a first-line option in advanced PDAC, and possibly in BTC, patients and prompts the continued evaluation of this approach in combination regimens.
Numerical modelling of discrete pile rows for slope stability and generic guidance for design
Authors: ELLIS E.A. , DURRANI I.K. , REDDISH D.J.
Published: February 2010

Discrete (spaced) pile rows are an established method of improving slope stability, or ‘dowelling' an existing slip. The piles predominantly provide horizontal restraint to the potentially unstable mass of the slope. The method becomes more cost effective as the pile spacing increases, but there is also increasing risk that the soil will ‘flow' through the gap between piles, rather than arching across it. Two- and three-dimensional numerical analyses of a generic slope with piles at various locations are undertaken. A simple model of the stabilising force required for a given increase in factor of safety of the slope is then combined with a model of limiting pile row interaction to allow direct estimation of the effect of piles at a particular spacing ratio in improving the factor of safety.
Deep-penetrating spudcan foundations on layered clays: numerical analysis
Authors: HOSSAIN M.S. , RANDOLPH M.F.
Published: February 2010

This paper presents results of large deformation finite element (LDFE) analyses that investigate the penetration response of deep-penetrating spudcan foundations in stratified soil comprising a strong clay layer overlying weaker clay. Such strength profiles give rise to potential punch-through failure, with a local maximum penetration resistance followed by some reduction. The paper is a companion paper to one that presents results from centrifuge model tests of the same problem, with the overall aim being to investigate the potential for punch-through failure and its severity, as a basis for improving design methods for evaluating spudcan penetration. The LDFE analyses have simulated continuous penetration of smooth and rough spudcan foundations from the sea-bed surface. A detailed parametric study has been undertaken, exploring the relevant range of layer thickness (relative to the spudcan diameter), strength ratios and spudcan base roughness. The results have been validated against previously published results and the centrifuge test data presented in a companion paper. Excellent agreement was obtained between the results from LDFE analyses and centrifuge tests. As the ratio of the shear strength of the bottom layer to that of the top layer decreased, upwards soil flow around the spudcan shoulder became less pronounced and the failure mechanism was dominated by a steep-sided plug of soil from the top layer being forced deep into the lower layer. The potential for severe punch-through was demonstrated by a significant reduction in the resistance profile as the spudcan approached the interface between the two layers. A preliminary design chart is proposed to estimate the cavity depth above the penetrating spudcan, which was significantly greater than that for a single layer clay. The penetration responses have been presented in terms of profiles of normalised net bearing pressure for a range of layer geometries and soil properties. Potential punch-through occurred for all cases where the strength ratio was less than or equal to 0·6, with the reduction in resistance being greater the lower the strength ratio of the underlying layer to the upper layer, and the thicker the upper layer, but reducing as the strength gradient in the lower layer increased. The current approach suggested in offshore design guidelines is shown to underestimate the penetration resistance significantly, in most cases, and give poor estimates of the likelihood and severity of spudcan punch-through.
Kinematics and rheology of a major landslide based on signal analysis
Authors: PYTHAROULI S.I. , STIROS S.C.
Published: February 2010

A detailed geodetic record, which is over 23 years old and describes the kinematics of the Mandria (or Left Bank Upstream) landslide – a major deep-seated landslide close to the Polyphyton dam, Greece – was analysed on the basis of advanced signal analysis techniques without any geotechnical constraints. It was found that all points share the same pattern of displacement, which characterises both short and longer records. The overall behaviour of the landslide can be described as viscoelastic and viscous or elastoviscous, with multi-annual periodic effects superimposed on the creep, as the results of spectral analysis indicate. The landslide seems insensitive to seasonal variations of precipitation and to annual fluctuations of the reservoir level, although the first filling of the reservoir is likely to have had an important role in its movement. There is a lack of subsurface information, but the available data indicate that the landslide corresponds to a rigid mass dominated by brittle behaviour and internal shearing, with its kinematics controlled by thin mylonitic layers along low- and high-angle faults.
Creep, strength and other characteristics of Hawaiian volcanic soils
Authors: BRANDES H.G. , NAKAYAMA D.D.
Published: February 2010

Strength, creep and other properties of four volcanic soils from Hawaii were investigated under reconstituted triaxial conditions. The selected soils are of different geological origin and have contrasting index properties. Results from triaxial tests suggest that as clayey volcanic soils weather toward a siltier texture, their response to loading changes accordingly, with dilation at larger strains leading to an increase in strength. The frictional strength of two of these soils, a high-plasticity clay from Manoa Valley in Honolulu and a young ash soil from the Hilo area, does not correlate well with conventional empirical relations. In terms of creep behaviour, the response under constant stress conditions can be described, at least to a first order, with a simple rate process equation. A constant that is a measure of strain rate attenuation with time is observed to be stress level dependent at lower deviatoric stresses, but relatively constant at higher stress levels. This constant may be related to plasticity index, although such a correspondence is tenuous at best. Strength gain is observed in post-creep undrained tests, and is attributed in part to prior volume changes and in part to ageing. In terms of changes to the short-term failure envelope, the effect of a sustained creep phase of 100 days or longer is to shift the failure line upward, albeit at a constant angle.
Stress–dilatancy relation for Mohr–Coulomb soils following a non-associated flow rule
Authors: ZHANG J. , SALGADO R.
Published: February 2010

Rowe's stress–dilatancy relation for frictional (cohesionless) materials has been a cornerstone of soil mechanics. The original derivation of this relationship was based on incorrect energy minimisation considerations, but the relationship was proven later by De Josselin de Jong using friction laws, and has been confirmed by a large body of experimental results. In contrast, the validity of Rowe's stress–dilatancy relation for cohesive-frictional materials, which has also been used, although not as extensively, was never verified. This paper shows that Rowe's stress–dilatancy relation for Mohr–Coulomb soils (cohesive-frictional materials) is in fact incorrect. The paper also provides a correct stress–dilatancy relationship for non-associated Mohr–Coulomb soils that have both cohesive and frictional strength components. The derivation of the relationship for cohesive-frictional soils presented in this paper relies on use of the sawtooth model together with the application of the laws of friction.
Modelling realistic shape and particle inertia in DEM
Authors: FERELLEC J. , McDOWELL G.
Published: February 2010

The use of clumps of overlapping spheres in DEM can be used to represent realistic particle shapes. This Technical Note discusses a method that is simple and fast, and highlights the key parameters influencing particle resolution. However, the problem with overlapping mass is that the density is non-uniform, which leads to incorrect moments of inertia and therefore rotational resistance. This Technical Note addresses this issue, and proposes a simple method to reduce the error in the principal moments of inertia. The effect on a falling heap of ballast particles is shown; the method improves not only behaviour, but also computational time.
Sustainable soil improvement via vacuum preloading
Authors: Indraratna B. , Rujikiatkamjorn C. , Kelly R. , Buys H.
Published: February 2010

The application of prefabricated vertical drains combined with vacuum and surcharge preloading is considered to be one of the most environmentally friendly ground improvement techniques. The natural atmospheric pressure is used to generate suction via a vacuum pump. In comparison with other ground improvement methods such as deep piling and deep mixing, this method will not only save a substantial cost in road and rail embankment maintenance and construction but will also enhance the speed of construction of coastal highways and rail tracks and their capacity to carry a greater traffic load. Moreover, as drains with vacuum pressure do not involve chemicals, the soil and groundwater chemistry will not change, unlike cement and lime treatment. Vacuum preloading will also reduce the impact on the environment by minimising the greenhouse gas emissions and the need for quarrying natural sand and gravel. The performances of three full-scale test embankments constructed in Thailand, China and Australia are discussed collectively, demonstrating the advantages and environmental benefits of vacuum consolidation in relation to a standard surcharge-only system.
Sustainable binders for soil stabilisation
Authors: Jegandan S. , Liska M. , Osman A. A-M. , Al-Tabbaa A.
Published: February 2010

Portland cement is the most commonly and widely used binder in ground improvement soil stabilisation applications. However, many changes are now affecting the selection and application of stabilisation additives. These include the significant environmental impacts of Portland cement, increased use of industrial by-products and their variability, increased range of application of binders and the development of alternative cements and novel additives with enhanced environmental and technical performance. This paper presents results from a number of research projects on the application of a number of Portland cement-blended binders, which offer sustainability advantages over Portland cement alone, in soil stabilisation. The blend materials included ground granulated blastfurnace slag, pulverised fuel ash, cement kiln dust, zeolite and reactive magnesia and stabilised soils, ranging from sand and gravel to clay, and were assessed based on their mechanical performance and durability. The results are presented in terms of strength and durability enhancements offered by those blended binders.
Demonstrating environmental benefits of ground improvement
Authors: Egan D. , Slocombe B. C.
Published: February 2010

Many ground improvement methods generate much less environmental impact than other deep foundation methods, for example concrete piling. Creative use of various ground improvement methods has already generated tangible benefits to completed projects, such as the Dartford Park project in the UK. The experience gained in these ground improvement projects highlights where further use of proven and emerging technology can provide still greater opportunity to reduce the environmental impact of deep foundation systems. The present study compared the environmental impact of common methods of ground improvement against more traditional deep foundation methods to show that, using a like-for-like comparison, ground improvement methods can offer sustainability advantages. Case studies illustrate how sustainable principles have been implemented in practical ways on routine projects. Perceived barriers and constraints that may hinder realisation of greater sustainability advances are identified and some suggestions as to how these may be overcome are presented.
Emissions assessment related to vibro stone columns
Authors: Jefferson I. , Gaterell M. , Thomas A. M. , Serridge C. J.
Published: February 2010

This paper investigates a number of issues significant to the evaluation of the sustainability of vibro stone columns and, in so doing, discusses how a carbon dioxide emissions estimation tool could be developed for this area of ground improvement. It involves consideration of the use of recycled/secondary aggregates and how this choice affects the column design process, in terms of the durability of constructed works and the amounts of aggregates required. The paper concludes that assessing the sustainability of vibro stone column construction, in carbon dioxide emissions terms, is a complex process not based simply on whether recycled/secondary aggregates themselves are more ‘environmentally friendly' than primary aggregates. Instead, it requires care on the part of ground improvement engineers, who must balance geographical variation of aggregate sources against the amount of aggregate used in the vibro stone column construction. However, it is noted that the use of carbon dioxide provides a limited view of sustainable performance, and that the continued development of emerging assessment tools could help capture some of the true complexity of the decision-making process.
Fracture parameters of high-strength concrete – mode II testing
Authors: Kumar C.Naga Satish , Rao T.D.Gunneswara
Published: February 2010

This paper presents an experimental investigation on fracture parameters (fracture energy and brittleness number) of double-edge-notched, high-strength concrete specimens of different sizes with varying notch depth ratios under mode II testing. Fracture energy and brittleness number are the important parameters for modelling the fracture behaviour of concrete. The fracture parameters are calculated by using size effect law. The size effect indicates that the failure stress of geometrically similar structures decreases with increasing size. From the experimental results it is observed that shear fracture energy (GII) is about 23 times more than that of mode I fracture energy (G1). It is also observed that the cracks do not propagate from the notches in the direction normal to the maximum principal stress but in a direction in which shear stresses dominate as reported by Bazant. The crack propagation direction seems to be governed by maximum energy release rate.
Determination of the transport properties of a blended concrete from its electrical properties measured during a migration test
Authors: Lizarazo-Marriaga J. , Claisse P.
Published: February 2010

The Nernst–Planck equation describes ionic movements in saturated porous materials subject to chemical concentration gradients in the pore fluid and applied electric fields. When applied to a macroscopic system the equation supposes that the flux of each ion is independent of every other one. However, owing to the ionic exchange among different or similar species, there are ionic potentials that affect the final flux. These will distort the applied electric field and thus keep the electroneutrality of the sum of all the ionic species involved. The applied potential will fall linearly across the sample but an additional ‘membrane' potential will change with position and time. This paper summarises a theoretical and experimental investigation into the application of the non-linear electric membrane potential to the simulation of the migration of chlorides in concrete. A new electrochemical test has been developed and carried out with different samples of concrete blended with pulverised fuel ash (PFA) and ground granulated blastfurnace slag (GGBS). During the tests the transient current and the electrical membrane potential were measured. A numerical model developed previously using the classical equations, but including changes in the concrete membrane potential, was optimised using an artificial neural network (ANN). Based on the experimental results and the simulations, the intrinsic diffusion coefficients of chloride, hydroxide, sodium and potassium were obtained. Also, the initial hydroxide composition of the pore solution, the porosity, and the chloride binding capacity were determined. The results showed good agreement with the theory and can help to explain the complex phenomena that occur during a concrete migration test.
Penetrability of lightweight aggregate concrete
Authors: Emiko L. , Wee T.H. , Tamilselvan T.
Published: February 2010

In this paper, a study was conducted on the parameters affecting the sorption of water, chloride ingress and permeability of water into lightweight aggregate concrete. The parameters being studied are the effects of the water-to-cement (w/c) ratio, aggregate type, initial moisture content of the lightweight aggregate, size of the lightweight aggregate, density of the lightweight aggregate, cement paste volume and volume of the lightweight aggregate. Experimental programmes were designed to look into the effects of these parameters on the penetration of water and free chloride ions into lightweight aggregate concrete by water sorption under capillary action in unsaturated concrete, chloride diffusion under a constant concentration gradient, and water permeability under a constant pressure gradient. From this research, it was found that variations in the w/c ratio, cement paste volume, as well as size, density and volume of the lightweight aggregate, have reasonable effects on penetrability properties of lightweight aggregate concrete. The effect of initial moisture content in the lightweight aggregate on properties of lightweight aggregate concrete is not obvious from this research.
Shear behaviour of RC beams strengthened with NSM and EB CFRP strips
Authors: Lim D.H.
Published: February 2010

The purpose of this study is to investigate the shear strengthening effectiveness of beams reinforced with near-surface-mounted (NSM) carbon-fibre-reinforced plastic (CFRP) strips and externally bonded reinforcing (EBR) CFRP strips. To accomplish this objective, a total of nine concrete beams were tested. From this study, it is found that the shear stiffness and strength of the beams reinforced by combined NSM and EBR strips were significantly improved compared to the control beam. Failure of the beam reinforced with NSM and EBR strips was initiated by shear cracks, propagated diagonally to the adjacent epoxy grooves without crossing the epoxy, and finally a sudden diagonal crack occurred connecting the point of application of load and the flexural crack. At failure, it was observed that the NSM strips appeared to be well bonded to the concrete. The tensile strains measured in the CFRP strip at the ultimate stage for the beam series strengthened with EBR strips were within the range 700–1200 με, with an average value of 1000 με. For the beam strengthened with combined NSM and EBR CFRP strips, however, the tensile strains in the NSM CFRP strips were found to be in the range 3500–4500 με and strains with EBR strips were measured at around 3000 με. This result shows that the NSM and EBR strips form a good combination to resist applied load and the combined reinforcement of NSM and EBR strips can redistribute the total stress to which the concrete beam is subjected on to the EBR and NSM strips.
Briefing: Making massive small change
Authors: Campbell Kelvin
Published: February 2010

‘The old delivery models are broken’ according to Sir Bob Kerslake of the UK Homes and Communities Agency. But are these models dead or just sleeping? Some would be inclined to blame the current recession for breaking the models. ‘It will all get better,’ they say, ‘when confidence returns.’ Others would say the models were broken long before the recession. Did society really get it right before or was it just flogging a dead horse? Like many recently failed UK high-street chains, they would say that the recession did not kill the business, it merely buried it. So is this a time to reflect and change approaches or is a paradigm shift upon us, whether welcome or not?
Gated communities: definitions, causes and consequences
Authors: Roitman S.
Published: February 2010

Gated communities became an ‘object of study’ in the 1990s as social scientists observed their growth in several cities; they are now a feature of the urban landscape in most cities around the world. The expansion of gated communities has led to prolific research, examining different aspects of this type of residential development and providing evidence from case studies worldwide. This paper reviews how gated communities are conceptualised according to the literature and identifies the main factors influencing their development. It also considers spatial, economic, political and social consequences of the development of gated communities. These elements should be taken into account by planners and policy-makers to minimise their negative impacts and maximise the positive consequences of a residential option that is likely to be part of the urban landscape for a long time.