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Background and Aims: It has become clear that vein resection and reconstruction for pancreatic ductal adenocarcinoma (PDAC) is the standard of care as supported by multiple guidelines. However, resection of large peri-pancreatic arteries remains debatable.Materials and Methods: This review examines the current state of vascular resection with curative intent for PDAC in the last 5 years. Herein, we consider venous (superior mesenteric vein, portal vein), as well as arterial (superior mesenteric artery, celiac trunk, hepatic artery) resection or both with or without reconstruction.Results: Improvement of multidrug chemotherapy has revolutionized care for PDAC that should shift traditional surgical thinking from an anatomical classification of resectability to a prognostic and biological classification.Conclusion: The present review gives an overview on the results of pancreatectomy associated with vascular resection, with consideration of new perspectives offered by the availability of better systemic therapies.

Abstract:As the Francophone world continues to be explored by scholars and students at all levels, more and more people are discovering the diversity of Francophone cultures and linguistic varieties of French found within the borders of the United States today. The French immersion schools of Louisiana are one manifestation of the unique francophonie comtemporaine des États-Unis. This article addresses problems faced by educators teaching in the immersion context in Louisiana. Twelve French immersion teachers were interviewed; the data collected produced ten key issues. Participants’ and author’s suggestions are then shared on how to strengthen the already successful Louisiana immersion model.

We have previously demonstrated a relationship between dry matter (DM) intake and the degree of transfer of radiocaesium to the muscle of adult sheep. Here, we present the results of an experiment during which we examined the effect of lamb growth and protein turnover rates, brought about by controlling feed DM intakes, on radiocaesium transfer and turnover. Lambs with high DM intakes and, as a consequence, high rates of growth, had a lower mean radiocaesium transfer coefficient from the diet to muscle than lambs with lower intake and growth rates. Furthermore, high rates of dry matter intake decreased the biological half-life of radiocaesium from muscle. The administration of [35S]-methionine to the study lambs enables us to suggest that radiocaesium transfer may be related to protein turnover. When the results were compared with those of other studies using sheep, a consistent relationship between DM intake and radiocaesium transfer across all animals regardless of age or physiological status was observed. Extrapolation of the relationship to DM intake rates appropriate to cattle predict radiocaesium transfer coefficients in broad agreement with reported values.

An assessment of the natural radiation dose to wildlife in England and Wales was made to determine the contribution it may make to the total radiation dose estimated during environmental impact assessments. Significant use was made of systematic datasets for environmental media (stream sediments, stream waters and soils), in particular those produced by the Geochemical Baseline Survey of the Environment (G-BASE) project. This provided extensive, although variable, coverage for different elements and sample types after normalisation of data to account for changes in sampling and analysis over time. Almost complete coverage for K in stream sediments was achieved by merging G-BASE and Wolfson Atlas data. This required normalisation of the Wolfson data to the G-BASE results. Coverage was improved greatly for U and Th in sediments, and K, U and Th in soils, by using the strong relationship between soils and sediments and geology (both solid and superficial) to extrapolate the data. The total U, Th and K data were used to derive activity concentrations of 238U and 232Th series radionuclides and 40K. External dose rates to wildlife were then estimated from derived media concentrations; internal dose rates were estimated from measured activities in biota or activities predicted using recommended concentration ratios.

There is general international acceptance of the need to demonstrate that the environment is protected from ionising radiation. In some countries requirements and guidelines for the protection of non-human biota are already in place. As a consequence a number of models and approaches have been proposed for the estimation of the exposure of non-human biota to ionising radiation. The IAEA EMRAS programme's Biota Working Group has conducted the most comprehensive intercomparison of the predictions of these approaches to date. In this paper, we present an overview of the activities of the Biota Working Group concentrating on its conclusions and recommendations.

Assessments of radiation exposure of reptiles may be required in some countries as many species are protected. However, there are few data available for the transfer of radionuclides to them, especially in terrestrial ecosystems, and consequently, no specific peer reviewed reptile data have been used in the derivation of default transfer parameters in the ERICA Tool. Twenty samples of Lacerta agilis(sand lizard) and five of Natrix natrix(grass snake) were collected from two sites within the Chernobyl Exclusion Zone and analysed for Pu-isotopes, 137Cs and 90Sr. Corresponding activity concentrations for soil from the sampling sites were available. These data have been used to derive concentration ratios (CR) (i.e. reptile whole-body fresh weight activity concentration relative to the dry weight activity concentration in soil). CR values for N. natrixtended to be lower than those for L. agilis. The CR values derived in this paper will be used to improve the default values provided within the ERICA Tool. Whole-body activity concentrations determined in the reptile samples were broadly comparable with data available from the same sampling sites for small mammal species.

Women who were sent home from hospital in the latent phase of labour were asked to keep a diary to reflect on their experiences. Twenty-one women consented to complete the diary but only six returned it. These six women were approached to participate in a one-to-one interview at home to further explore the effects of being discharged home. Five women agreed to be interviewed. Interviews were tape-recorded and transcribed verbatim. The data were analyzed using latent content analysis. Five themes were identified: influence of others, reassurance, coping/pain, sleep deprivation and undervaluing of the latent phase. Women were strongly influenced regarding when to go into hospital by the anxiety of family and partners. Most women sought reassurance but being sent home made them feel unsupported and this may have increased their anxiety. Further research is needed into how best to support women planning a hospital delivery who in the latent phase of labour at home.

The influence of peptide/protein size and hydrophobicity on the physical and chemical aspects of loading within porous silicon (pSi) wafer samples has been determined using Atomic Force Microscopy (AFM) and Time-of-Flight Secondary Ion Mass Spectroscopy (ToF-SIMS). Both Gramicidin A (a small hydrophobic peptide) and Papain (a larger hydrophilic protein) were observed (ToF-SIMS) to penetrate across the entire pSi layer, even at low loading levels. AFM surface imaging of pSi wafers during peptide/protein loading showed that surface roughness increased with Papain loading, but decreased with Gramicidin A loading. For Papain, the loading methodology was also found to influence loading efficiency. These differences indicate more pronounced surface adsorption of Papain. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Porous silicon (p-Si) has been investigated as a novel delivery system for protein therapeutics. The loading of a model hydrophilic protein, Papain into anodised and stain etched p-Si powders has been investigated using X-ray photoelectron spectroscopy (XPS) and infrared spectroscopy (FTIR) and correlations made with the release kinetics. Variation in specific Papain (Amide I/II) and p-Si (Si–Hx) functional group absorbances with Papain loading level was characterised using FTIR, while the surface chemical distribution was assessed using XPS. A combination of burst release and sustained release of Papain was observed from p-Si powders; this was dependent on p-Si type and the Papain loading level. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The article relates how the U.S. 3rd Battalion, 327th Infantry Regiment or the Battle Force had seen combat throughout Iraq prior to a successful mission that led to the death of Saddam Hussein's two sons, Uday and Qusay. The task force occupied the northeast sector of Mosul beginning in late May 2003 and conducted civil-military operations and offensive operations leading up to the raid that killed Saddam Hussein's two sons.

In this paper we use the FASSET framework to estimate absorbed dose rates for biota within the Chernobyl exclusion zone. The estimated doses are compared to observed biological effects within the Chernobyl exclusion zone and effects expected from summaries of existing knowledge and the extent of contamination. Although paucity of observations under conditions of chronic irradiation makes direct comparison difficult, the biological effects observed in the Chernobyl exclusion zone over the period considered here (1988-2003) are broadly in agreement with those which may have been expected.

A number of frameworks have been proposed to assess the protection of wildlife from ionising radiations. In this paper we compare the predictions of transfer parameters recommended by one of these frameworks (FASSET) with observed whole-body 90Sr and 137Cs activity concentrations in a range of mammal and invertebrate species sampled within the Chernobyl exclusion zone. Predicted activity concentrations are generally within the observed ranges and mean predictions for reference organisms are similar to, or circa one order of magnitude higher than, the observed means. However, some predictions are more than one order of magnitude lower than observed values. No data were available for animals to test predictions for the other radionuclides released by the Chernobyl accident. In a separate paper the outputs of this assessment will be used to estimate doses to reference organisms and compare these to observed radiation induced effects reported within the Chernobyl zone.

We review collated data and available models for estimating the transfer of radionuclides to terrestrial biota within the European Arctic. The most abundant data are for radiocaesium and radiostrontium although many data for natural radionuclides are available. For some radionuclides no data are available for describing transfer to Arctic biota. Allometric-kinetic models have been used to estimate transfer for radionuclide-biota combinations. Predicted values were in good agreement with observed data for some radionuclides although less so for others. There are no bespoke models to enable the dynamic prediction of radionuclide transfer to Arctic biota. A human Arctic foodchain model has been adapted to estimate 137Cs and 90Sr transfer to some Arctic biota. There are many factors of Arctic ecosystems which may influence radionuclide behaviour including short growing seasons, prolonged soil freezing, and effects of low temperatures on biological rates. If exposure to ionising radiation in Arctic ecosystems is to be robustly predicted such factors must be fully understood and incorporated into models.

PCR analysis was used to detect Fusariumspecies generically, as well as the mycotoxin-producing species F.␣subglutinans, F. proliferatum, and F. verticillioidesin leaf axil and other maize tissues during ear fill in a multiyear study in central Illinois. The frequency of Fusariumdetected varied from site to site and year to year. Fusariumwas generically detected more frequently in leaf axil material than in leaf/husk lesions. In two growing seasons, the leaf axil samples were also tested for the presence of the mycotoxin producing species F. proliferatum, F. subglutinans, and F. verticillioides. Overall, F. proliferatumand F. verticillioideswere detected less often than F. subglutinans. Fusariumwas generically and specifically detected most commonly where visible fungal growth was present in leaf axil material.

Assessment of the transfer of radionuclides to wild species is an important component in the estimation of predicted doses to biota. Reviews of available data for the many potential radionuclide-biota combinations which may be required for environmental assessments highlight many data gaps for terrestrial species. Here, we discuss different approaches which have been suggested to compensate for these data gaps. All of the reviewed approaches have merit; however, there is a requirement for transparency in methodology and data provenance which in some instances is currently missing. Furthermore, there is a need to validate the various methodologies to enable their use with confidence. The requirements of improving our ability to predict radionuclide transfer to wild species are discussed and recommendations made.

Ambient concentrations of C₆–C₈ aromatic hydrocarbons and n-heptane, determined by gas chromatography with flame ionisation detection, are presented from a winter campaign during January 1999 at a rural site near Leeds. Absolute concentrations are significantly lower than those obtained from the only designated UK rural site (Harwell) in the automated UK hydrocarbon network. Both absolute and relative concentrations of hydrocarbons measured at the site have been interpreted in terms of the arriving back-trajectories. The site is subject to two main airflows during the winter months; relatively polluted air from the southwest and much cleaner air from the northwest. Ratios of hydrocarbon concentrations show evidence of significant chemical processing consistent with chemical removal by OH. Uncertainties in the ages of the trajectories prevent a reliable estimation of the average OH concentration over the trajectory. The dependence of the variance of the hydrocarbon concentrations with their lifetime with respect to removal by OH does not show the expected behaviour.

Abstract: Chromium-doped CdSe is one of the host materials being considered for solid-state tunable mid-infrared (IR) lasers. Alloying CdSe with CdS allows the increase of the thermal conductivity of the crystal (for CdS the thermal conductivity is a factor of 4 larger than CdSe), which is a favorable parameter as a laser host. In this study, we have grown CdSxSe1−x (x≅0.8) single crystals by the physical vapor transport (PVT) method. Crystals with dimensions of 1.2 cm in diameter and 5 cm in length, free of precipitates and inclusions, have been grown. Chromium ions were diffused into the crystal by a postgrowth-diffusion technique at 900C. Incorporation of Cr ion gives rise to a broad absorption peak at 1.87 m.

Abstract: A recently developed semi-mechanistic temporal model is used to predict food product radiocaesium activity concentrations using soil characteristics available from spatial soil databases (exchangeable K, pH, percentage clay and percentage organic matter content). A raster database of soil characteristics, radiocaesium deposition, and crop production data has been developed for England and Wales and used to predict the spatial and temporal pattern of food product radiocaesium activity concentrations (Bq/kg). By combining these predictions with spatial data for agricultural production, an area’s output of radiocaesium can also be estimated, we term this flux (Bq/year per unit area). Model predictions have been compared to observed data for radiocaesium contamination of cow milk in regions of England and Wales which received relatively high levels of fallout from the 1986 Chernobyl accident (Gwynedd and Cumbria). The model accounts for 56% and 80% of the observed variation in cow milk activity concentration for Gwynedd and Cumbria, respectively. Illustrative spatial results are presented and suggest that in terms of food product contamination areas in the North and West of England and Wales are those most vulnerable to radiocaesium deposition. When vulnerability is assessed using flux the spatial pattern is more complex and depends upon food product.

Postpartum and lactating crossbred cows containing a percentage of Bos indicusbreeding at three locations were studied to determine the efficacy of GnRH + PGF2αcombinations for synchronization of estrus and(or) ovulation. Cows were equally distributed to each of three treatments by body condition score at the start of the experiment (d 0). All cows received 100 μg of GnRH on d 0 and 25 mg of PGF2α7 d later. The three insemination protocols included 1) AI 12 h after exhibiting estrus during d 7 to 12 of the experiment (Select-Synch; n = 197); 2) timed-AI + 100 μg of GnRH on d 9 of the experiment (CO-Synch; n = 193); 3) AI 12 h after exhibiting estrus during d 7 to 10 of the experiment. Cows not exhibiting estrus by d 10 were timed-AI and injected with 100 μg of GnRH on d 10 of the experiment (Hybrid-Synch; n = 200). The percentage of cows exhibiting estrus during d 7 to 12 of the experiment was lower (P< 0.05) for CO-Synch (17.6%) cows than for Select-Synch or Hybrid-Synch (45.2 and 33.0%, respectively) cows, which did not differ (P> 0.05). For the Select-Synch and Hybrid-Synch cows that exhibited estrus during d 7 to 10 of the experiment and were artificially inseminated, conception rates were similar across treatments (50.5%). Pregnancy rates were greater (P< 0.01) for CO-Synch and Hybrid-Synch (31.0 and 35.5%, respectively) cows than for Select-Synch (20.8%) cows. A greater (P< 0.01) percentage of cycling cows became pregnant (34.5%) than noncycling cows (25.9%) across all treatments. The CO-Synch and Hybrid-Synch synchronization protocols resulted in greater pregnancy rates compared with the Select-Synch protocol in postpartum and lactating crossbred cows containing a percentage of Bos indicusbreeding.

Abstract: A study is described in which 137Cs intake by free-ranging sheep was estimated at two farms in the area of west Cumbria (northwest England) which received some of the highest amounts of fallout from the Chernobyl accident within the United Kingdom. The faecal excretion of 137Cs was estimated from faecal 137Cs activity concentrations and the use of intraruminal controlled release devices containing Cr2O3 to determine faecal dry matter output. The intake of 137Cs was estimated by assuming an apparent absorption coefficient appropriate to the herbage grazed. The methodology has the advantage that sampling of herbage representative of that ingested by study animals is not required. Caesium-137 dietary intake explained >60% of the observed variability in the 137Cs activity concentration determined in the muscle of sheep. Resultant transfer coefficient (F f ) values to describe the transfer of 137Cs from the diet to muscle were in agreement with previously reported values. At one farm, there was a positive correlation between the 137Cs activity concentration in muscle and F f whilst at the other farm there was a negative correlation between F f and 137Cs dietary intake. Potential reasons for these observations are discussed.

Objectives: The aim of this study was to characterize the motor events responsible for gastroesophageal reflux (GER) and esophageal acid clearance in a cohort of healthy preterm infants. Study design: Esophageal motility was recorded for 2 to 3 hours after a feeding in 24 preterm infants, 31 to 38 weeks' postmenstrual age, by using a sleeve-side hole micromanometric assembly incorporating a pH probe. Results: Sixty acid GER episodes were recorded by pH probe, and 133 non-acid GER episodes were recorded manometrically by the presence of esophageal common cavities. Of the 193 GER episodes, 159 (82%) were associated with transient lower esophageal sphincter relaxation (TLESR). TLESRs were significantly longer in duration than single swallows (15.1 seconds vs 5.6 seconds, P < .001) and had lower nadir pressures (0.8 mm Hg vs 2.3 mm Hg, P < .001). A total of 3216 esophageal body pressure waves were analyzed; 70% of swallow-induced pressure waves were peristaltic in sequence compared with 5% of swallow-unrelated pressure waves. During periods of esophageal acidification (pH below 4), peristaltic esophageal body pressure wave sequences cleared acid refluxate more effectively than nonperistaltic pressure wave sequences. Conclusions: In healthy preterm infants, TLESRs are the predominant mechanism underlying GER, and esophageal clearance mechanisms are well developed by at least 31 weeks' postmenstrual age. (J Pediatr 1998;133:650-4)

Abstract: Considerable variability has been recorded in the radiocaesium activity concentration of muscle between individual sheep in the same flocks in upland areas that received fallout from the Chernobyl accident. In a previous paper we demonstrated that there is a propensity for certain sheep within a flock to be always amongst the most contaminated and others to be consistently the least contaminated. Here we report a study to determine the extent to which variation in the metabolism of radiocaesium by individual sheep may contribute to the observed variability within sheep flocks. The transfer coefficient and biological half-life of orally administered ionic radiocaesium in muscle were determined under controlled conditions in 22 ewes from an upland farm in an area of the UK which received comparatively high levels of Chernobyl fallout. There was considerable variation between individuals in both the transfer coefficient (0.19–0.56 day⋅kg–1; mean 0.34 day⋅kg–1) and biological half-life in muscle (5.2– 18.7 days; mean 9.8 days). Changes in liveweight during the study and feed intake together accounted for 72% of the variation in the derived transfer coefficients; liveweight change also accounted for 56% of the observed variation in biological half-life. In a subsequent study, the true absorption coefficient of radiocaesium was determined in 12 of the ewes. There was a positive correlation between transfer and true absorption coefficients (R=0.57). We conclude that differences in the metabolism of radiocaesium will contribute to the observed variability in radiocaesium activity concentrations within sheep flocks in areas which were contaminated by Chernobyl fallout. We also suggest that for growing animals, the influence of liveweight change and feed intake on radiocaesium transfer may be greater than observed here. Similarly, in dairy cattle, for which feed intake changes considerably during the course of a lactation, large temporal variation in radiocaesium transfer to milk could be expected.

A concise and scalable synthesis of LY231514 (1), a new pyrrolo[2,3-d]pyrimidine-based antitumor agent, is presented. Reaction of 2-bromo-4-arylbutanal 9 with 2,4-diamino-6-hydroxypyrimidine (10) regioselectively provided pyrrolo[2,3-d]pyrimidine 11, representing the core structure of the drug, in good yield. Assimilation of the glutamic acid residue by conventional means completed the synthesis. Development of the optimized synthetic route emphasized avoiding isolation of the relatively unstable aldehyde and bromoaldehyde intermediates.

The vibrational circular dichroism of (S)-(+)-9,10-dihydrodibenzo[c,g]-phenanthrene has been obtained over the frequency region of the C-H stretching mode fundamentals. A major contribution to the vibrational optical activity of the CH2 groups is found to originate in the dynamic polarization of the naphthalene ring systems of the enantiomer by the transition dipole of the localized symmetric or antisymmetric C-H stretching mode of each group. An analogous mechanism accounts for the optical activity observed in the frequency region of the aromatic C-H stretching fundamentals.

The effect of magnesium-aluminum hydroxide antacid tablets or liquid on food-stimulated gastric acidity was evaluatedin vivo in eight duodenal ulcer patients. Experiments were performed alsoin vitro. Althoughin vitro neutralizing capabilities of the two preparations were the same (28.3±0.1 mmol/liter), the duration of effect of tablets was longerin vivo. For example, at 33/4 hr after an eaten meal, mean hydrogen ion concentration with three tablets was 29.8±9.9 mmol/liter while with 15 ml liquid it was 59.6±10.3 mmol/liter (P <0.05). Additional studies were performedin vitro to explain the longer duration of effect of tablets compared with liquidin vivo. These experiments suggested that tablets reacted more slowly with acid than did liquid and that saliva, which was mixed with tablets during chewing, also contributed to the prolonged duration of effect.

The effect of insulin-dependent diabetes on the hepatic microsomal activity of cytochrome P450III and P450IV family proteins was investigated in rats pretreated with streptozotocin. In order to discern between the effects of the diabetogen per se and those of the ensuing diabetes, streptozotocin-treated rats received in addition either nicotinamide to prevent the onset of diabetes or daily treatment with insulin to antagonize the effects of diabetes. Streptozotocin-treated rats displayed higher ethylmorphine and erythromycin N-demethylase activities and lauric acid hydroxylase activity. Increases were also detected immunologically by using monospecific polyclonal antibodies against the P450III and P450IV families. All effects were prevented by nicotinamide and effectively antagonized by insulin. In order to evaluate the role of the ketone bodies in the diabetes-induced increases in the above activities, rats were rendered hyperketonaemic by dietary administration of medium-chain triacylglycerols. These hyperketonaemic animals displayed high laurate hydroxylase activity and P450IV apoprotein levels, similar to those seen in the diabetic animals. Hyperketonaemia induced by dietary means caused a modest increase in the demethylation of erythromycin and had no significant effect on the N-demethylation of ethylmorphine. Furthermore, no marked increases were evident in the P450III apoprotein levels in the hyperketonaemic animals. It is concluded that insulin-dependent diabetes induces proteins of the P450III and P450IV families, and that the hyperketonaemia that accompanies diabetes is largely responsible for the changes in the latter family.