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Background: (131)I-metaiodobenzylguanidine (MIBG) is an active radiopharmaceutical in neuroblastoma. A previous study demonstrated that MIBG could be combined with vincristine and prolonged irinotecan, although 25% of first courses had grade 3 diarrhoea. The current phase I/II study evaluated MIBG with vincristine and 5 days of higher-dose irinotecan.Methods: Patients 1-30 years old with advanced neuroblastoma were eligible. Patients received cefixime on days -1 to +6, irinotecan (50 mg m(-2) per dose IV) on days 0-4, vincristine (2 mg m(-2)) on day 0, MIBG (555 or 666 MBq kg(-1)) on day 1, and peripheral blood stem cells on day 13. UGT1A1 genotyping was performed in consenting patients.Results: Thirty-two patients (12 phase I ; 20 phase II) received 42 courses. No dose-limiting toxicities were seen during dose escalation and the recommended administered activity was 666 MBq kg(-1). Myelosuppression and diarrhoea were the most common toxicities, with grade 3 diarrhoea in 6% of first courses. Patients homozygous for UGT1A1*28 had more grade 4 thrombocytopenia (80% vs 37%; P=0.14). Responses (five complete and four partial) occurred in 9 out of 32 (28%) patients.Conclusions: MIBG (666 MBq kg(-1)) with vincristine and this irinotecan schedule is tolerable and active, with less severe diarrhoea compared with a regimen using more protracted irinotecan. [ABSTRACT FROM AUTHOR]

Background:131I-metaiodobenzylguanidine (MIBG) is an active radiopharmaceutical in neuroblastoma. A previous study demonstrated that MIBG could be combined with vincristine and prolonged irinotecan, although 25% of first courses had grade 3 diarrhoea. The current phase I/II study evaluated MIBG with vincristine and 5 days of higher-dose irinotecan.Methods:Patients 1-30 years old with advanced neuroblastoma were eligible. Patients received cefixime on days −1 to +6, irinotecan (50 mg m−2 per dose IV) on days 0-4, vincristine (2 mg m−2) on day 0, MIBG (555 or 666 MBq kg−1) on day 1, and peripheral blood stem cells on day 13. UGT1A1 genotyping was performed in consenting patients.Results:Thirty-two patients (12 phase I ; 20 phase II) received 42 courses. No dose-limiting toxicities were seen during dose escalation and the recommended administered activity was 666 MBq kg−1. Myelosuppression and diarrhoea were the most common toxicities, with grade 3 diarrhoea in 6% of first courses. Patients homozygous for UGT1A1*28 had more grade 4 thrombocytopenia (80% vs 37%; P=0.14). Responses (five complete and four partial) occurred in 9 out of 32 (28%) patients.Conclusions:MIBG (666 MBq kg−1) with vincristine and this irinotecan schedule is tolerable and active, with less severe diarrhoea compared with a regimen using more protracted irinotecan. [ABSTRACT FROM AUTHOR]

The search for sustainability achievement in the building sector led to the use of crop-based insulation materials. Among these, raw products like plant straws bales can present elementary representative volumes in the size order of several square centimeters. Fibers orientation may play an important role on material thermal behavior. Measuring their thermal conductivities with standard steady-state equipment can thus lead to some inaccuracies due to the necessity of resetting lower thickness samples. This paper presents a guarded hot plate apparatus designed to test high thickness samples, up to 40 cm, with an accuracy of 2 %. The different parts of the machine are described in details along with design process and challenges encountered. Temperature and heat flux measurements in the device represent critical design stages where optimal accuracy is needed in order to optimize the resulting global error. Regarding this, necessary numerical and experimental analyzes were conducted emphasizing on intrinsic systematic error assessment. To complete the study, some validations tests are performed on a reference material and other widely-spread polystyrene slabs. These tests take into account the optimal computation parameters resulting from the numerical analysis and the apparatus proved to be in accordance with accuracy requirements. [ABSTRACT FROM AUTHOR]

Starting from a mixture of Al-Cu-Fe quasicrystalline (QC) particles and Al powder, a fully dense and almost Al-Cu-Fe ω single-phase alloy was produced by spark plasma sintering. This technique allows synthesising large samples with sizes suitable for mechanical spectroscopy experiments. Mechanical spectroscopy was selected because it is a relevant tool for detecting the presence of structural defects at both nano and microscopic scales. Young's moduli were measured in the 15 kHz range as a function of temperature by the resonant frequency method. Young's moduli behave similarly for typical metals and exhibit values that are comparable to those of the Al-Cu-Fe QC phase. The damping coefficient Q was determined at various temperatures between room temperature and 840 K over a large frequency range, i.e. between 10 and 10 Hz. The results suggest that solid friction effects do occur. In addition, a relaxation peak is observed in the intermediate temperature range. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) and graphene nanoribbons (GNRs) represent a novel class of low-dimensional materials. All these graphene-based nanostructures are expected to display the extraordinary electronic, thermal and mechanical properties of graphene and are thus promising candidates for a wide range of nanoscience and nanotechnology applications. In this paper, the electronic and quantum transport properties of these carbon nanomaterials are reviewed. Although these systems share the similar graphene electronic structure, confinement effects are playing a crucial role. Indeed, the lateral confinement of charge carriers could create an energy gap near the charge neutrality point, depending on the width of the ribbon, the nanotube diameter, the stacking of the carbon layers regarding the different crystallographic orientations involved. After reviewing the transport properties of defect-free systems, doping and topological defects (including edge disorder) are also proposed as tools to taylor the quantum conductance in these materials. Their unusual electronic and transport properties promote these carbon nanomaterials as promising candidates for new building blocks in a future carbon-based nanoelectronics, thus opening alternatives to present silicon-based electronics devices. [ABSTRACT FROM AUTHOR]

Objective:To determine whether the mRNA concentrations of inflammation response genes in isolated adipocytes and in cultured preadipocytes are related to adipocyte size and in vivo insulin action in obese individuals.Design:Cross-sectional inpatient study.Subjects:Obese Pima Indians with normal glucose tolerance.Measurements:Adipocyte diameter (by microscope technique; n=29), expression of candidate genes (by quantitative real-time PCR) in freshly isolated adipocytes (monocyte chemoattractant protein (MCP) 1 and MCP2, macrophage inflammatory protein (MIP) 1α, MIP1β and MIP2, macrophage migration inhibitory factor (MIF), tumor necrosis factor α, interleukin (IL) 6 and IL8; n=22) and cultured preadipocytes (MCP1, MIP1α, MIF, IL6 and matrix metalloproteinase 2; n=33) from subcutaneous abdominal adipose tissue (by aspiration biopsy, n=34), body fat by dual-energy X-ray absorptiometry, glucose tolerance by 75 g oral glucose tolerance test and insulin action by euglycemic-hyperinsulinemic clamp (insulin infusion rate 40 mU m−2 min−1) (all n=34).Results:MIF was the only gene whose expression in both freshly isolated adipocytes and cultured preadipocytes was positively associated with adipocytes diameter and negatively associated with peripheral and hepatic insulin action (all P<0.05). In multivariate analysis, the association between adipocyte MIF mRNA concentrations and adipocytes diameter was independent of the percentage of body fat (P=0.03), whereas adipocyte MIF mRNA concentrations, but not adipocyte diameter, independently predicted peripheral insulin action. The mRNA expression concentrations of the MIF gene in adipocytes were not associated with plasma concentrations of MIF, but were negatively associated with plasma adiponectin concentrations (P=0.004). In multivariate analysis, adipocyte MIF RNA concentrations (P=0.03) but not plasma adiponectin concentrations (P=0.4) remained a significant predictor of insulin action.Conclusions:Increased expression of MIF gene in adipose cells may be an important link between obesity characterized by enlarged adipocytes and insulin resistance in normal glucose tolerant people.International Journal of Obesity (2009) 33, 842–850; doi:10.1038/ijo.2009.106; published online 9 June 2009 [ABSTRACT FROM AUTHOR]

Thermite reactions in the NiO-Al system have been studied. In addition to the case when the stoichiometry is set up to produce metallic nickel and alumina, we studied the case when Al is added in excess in order to react with the Ni produced through the reduction of nickel monoxide with Al to produce various nickel aluminides. As thermite reactions are highly exothermic, in order to provide a better understanding of the reactions, alumina has been added to the green mixture to reduce the reaction rate and overall exothermicity, in amounts corresponding up to 50% of the overall heat capacity of the sample. [ABSTRACT FROM AUTHOR]

Neonatal umbilical anomalies usually represent remains of the vitelline duct or the allantois. We describe a case of an umbilical appendix in a neonate. The vermiform appendix was found to be positioned in the umbilical cord. In a brief literature review we found eight other reports concerning umbilical appendices. In this article we describe a possible embryological explanation for the development of an umbilical appendix, and discuss whether or not the appendiceal umbilical fistulae reported are congenital or iatrogenic. The possible association between an umbilical appendix and different forms of malpositioning and rotation of the gut is also discussed. Protrusion of the neonatal appendix into the umbilical cord represents a different entity of congenital anomalies. It is important to realize that, in the case of an unrecognized umbilical appendix, medical procedures (e.g., canulation or clamping of the umbilicus) may produce an iatrogenic appendico-umbilical fistula. Careful inspection and palpation of the umbilical cord prior to these procedures may prevent a fistula being created. Furthermore, because the possible association between umbilical appendices and different kinds of malpositioning of the gut is so far not wholly elucidated, we recommend further (radiological) investigation in each case of an umbilical appendix. Correct positioning of the bowel needs to be confirmed in order to rule out possible future complications. [ABSTRACT FROM AUTHOR]

: A simple method to calculate thermal diffusivity in situ after a combustion synthesis reaction is presented. The combustion reaction was analyzed via time-resolved X-ray diffraction analysis and infrared thermography. Thermal diffusivity was estimated and used to calculate temperature profiles based on temperature profiles one second earlier. For a sample of TiC formed from Ti and C, a value of 2.00×10-6±0.20×10-6 m2 s-1 was calculated for temperatures between 1000 and 1900 K. This method is rapid and can avoid some problems associated with furnace-based measurements of thermal diffusivity, such as recrystallization and destruction of non-equilibrium phases. [ABSTRACT FROM AUTHOR]

Titanium carbide was synthesized from self-propagating high temperature synthesis (SHS) performed under isostatic gas pressure ranging from 70 bars up to 700 bars. Propagation conditions of the combustion reaction have been studied as a function of gas pressure for C reactant of different diameters (20 μm and 7 μm). For coarse particles, the reaction stops upon increasing pressure, while for fine particles, reaction self-propagates up to 700 bars. It is shown that this change in propagation conditions can be explained by considering both thermal and kinetic effects. Finally, TiC formation mechanisms are discussed for SHS performed under high isostatic pressure. [ABSTRACT FROM AUTHOR]

Self-propagating high-temperature synthesis was performed on an equimolar mixture of titanium and graphite embedded in a copper tube of variable thickness. Such an experimental setup allows us to study the interaction between the reaction front and copper. Special attention was focused on copper melting, copper penetration within the sample, and quenching of the sample: it is shown that a minimum of 1 mm for the copper thickness is necessary to ensure the physical integrity of the surrounding metal. Nevertheless, reaction is not complete under these conditions. As a consequence, copper is not the most appropriate metal for field assisted combustion synthesis electrodes. As for thermal explosion and high isostatic pressing combustion synthesis, some valuable insights are provided, and a metal with slightly lower thermal diffusivity, lower electrical conductivity, and/or higher melting temperature would likely be a good candidate for such applications. [ABSTRACT FROM AUTHOR]

Resistivity measurements have been performed on silicon powder beds with different thicknesses which were submitted to uniaxial pressure (0-640 MPa). For the smallest thicknesses of the Si pellets, the pressure dependence of conductivity may be described using models based on effective medium theory or strongest stresses network. For largest Si thicknesses, it exists an inhomogeneous distribution of pressure in the granular medium as a consequence of arching effects. It is shown that the conductivity variation with Si powder thickness may be understood using a distribution of conductivity induced by the distribution of pressure. Finally, it is shown that the conductivity of the sintered Si pellets is correlated with the uniaxial compression step. [ABSTRACT FROM AUTHOR]

Titanium carbide was synthesized from self-propagating high-temperature synthesis performed under isostatic gas pressure. Carbon and titanium particles of mean diameters of 7 or 20 μm and 17 μm, respectively, were used as reactants. The final product was analyzed by X-ray diffraction and scanning electron microscopy. Porosity was carefully determined by different methods. For a reactant mixture with coarse C particles, the large value of the closed porosity (22%) is shown to be compatible with the emptying core model. The origin of such a predominant mechanism in pure C and Ti mixture is tentatively discussed. [ABSTRACT FROM AUTHOR]

Macroscopic resistivity measurements have been performed on TiC/Al2O3 random mixtures submitted to uniaxial compression (0-95 kN). Such a random mixture exhibits an insulator-conductor transition which appears at increasing force while decreasing the conductive composition of the TiC/Al2O3 mixture. It is demonstrated that the conductivity behavior may be understood in the framework of a site percolation model. Finally, the rate of creation of the contacts between conductive grains is extracted from the macroscopic resistivity measurements. [ABSTRACT FROM AUTHOR]

The magnetic anisotropy and domain structure of electrodeposited cylindrical Co nanowires with length of 10 or 20 μm and diameters ranging from 30 to 450 nm are studied by means of magnetization and magnetic torque measurements, as well as magnetic force microscopy. Experimental results reveal that crystal anisotropy either concurs with shape anisotropy in maintaining the Co magnetization aligned along the wire or favours an orientation of the magnetization perpendicular to the wire, hence competing with shape anisotropy, depending on whether the diameter of the wires is smaller or larger than a critical diameter of 50 nm. This change of crystal anisotropy, originating in changes in the crystallographic structure of Co, is naturally found to strongly modify the zero (or small) field magnetic domain structure in the nanowires. Except for nanowires with parallel-to-wire crystal anisotropy (very small diameters) where single-domain behaviour may occur, the formation of magnetic domains is required to explain the experimental observations. The geometrical restriction imposed on the magnetization by the small lateral size of the wires proves to play an important role in the domain structures formed. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 25-year-old man who was admitted to the hospital with complaints of acute erythroblastic leukemia relapse. He underwent a consolidation chemotherapy consisting of clofarabine and cytarabine. After receiving valaciclovir antiviral prophylaxis, he developed symptoms of anterograde amnesia. His neuropsychological testing reported problems in the cognitive functioning.

A theory, based on earlier work by Valet and Fert, is first presented to describe the influence of temperature on the perpendicular giant magnetoresistance (GMR) in multilayers. Then we present GMR measurements performed at T=77 K and at room temperature on Co/Cu multilayered nanowires with layer thicknesses ranging from a few nm to 1 μm. We use our model to obtain a good quantitative fit to the experimental results in both the short spin diffusion length limit and out of this limit. We discuss the temperature dependence of the bulk parameters, the scattering spin asymmetry coefficient and spin diffusion length in the Co layers. [ABSTRACT FROM AUTHOR]

The frequencies of cell degeneration and mitosis were investigated in the rupturing buccopharyngeal membrane (BPM) and in the persistent first branchial membrane (BM). In the BPM, cell degeneration starts many hours before rupture is visible, but mitotic figures are absent. In the BM this situation is reversed: mitotic figures are regularly observed, but a degenerating cell only occasionally. It is concluded that the ratio between the numbers of degenerating and dividing cells regulates the fate of both the BPM and the BM. [ABSTRACT FROM AUTHOR]

Objectives: An increase of intraepithelial lymphocytes (IEL) is commonly found in lymphocytic colitis (LC) and collagenous colitis (CC), and has also been observed in the colonic mucosa of some patients with celiac disease or celiac-like disease. Thus, a similar mechanism could play a role in these apparently different entities. The aim of this work was to determine the phenotype of IEL and of lamina propria lymphocytes in the setting of LC and CC. Methods: Biopsies were taken from all segments of the large bowel and from the ileon of eight patients with CC, four patients with LC, and 10 controls. An immunohistochemical study using monoclonal antibodies directed against IEL, T-cells, helper T-cells, suppressor/ cytotoxic T-cells, HLA DR antigens, T-cell-bearing T-cell receptor (TcR) αβ, and TcR γδ was carried out. Results: There was an increase in mean numbers of IELs in both LC and CC, with significantly more CD 8 IELs than CD 4 IELs. Most IELs were bearing TcR alpha;β; TcR γδ-bearing cells were not increased in CC or LC. CD 4+ helper T-cells predominated in the lamina propria. Epithelial cells of colonic mucosa abnormally expressed HLA DR antigens. There were no significant differences between findings in LC and CC. Conclusion: This study suggests that the immune abnormalities are similar in LC and CC and that a MHC-restricted immune mechanism could be involved in both diseases. Evidence for this includes: I) the accumulation of CD 4+ T-cells within the lamina propria, 2) epithelial damage closely related to the increase of CD 8 TcR αβ IELs, and 3) abnormal class II MHC molecule expression on epithelial cells of colonic mucosa. Furthermore, the results suggest that the putative immune mechanisms underlying LC or CC are probably different from those that are incriminated in celiac disease. [ABSTRACT FROM AUTHOR]

We have synthesized microspheres from aqueous solutions of simple molecules submitted to sonolysis at 20 kHz and 800 kHz in an argon atmosphere. Photochemical reaction under room light or UV-irradiation yielded the same microstructures, whose formation has been studied with optical and electronic microscopes. [ABSTRACT FROM AUTHOR]

Microvascular dysfunction may have an early onset in type 1 diabetes (T1D) and can precede major complications. Our objectives were to assess the endothelial-dependent (acetylcholine, ACh; and post-occlusive hyperemia, PORH), non-endothelial-dependent (sodium nitroprusside, SNP) and neurovascular-dependent (local heating, LH and current induced vasodilation, CIV) microcirculatory vasodilation in T1D patients compared with matched control subjects using a laser speckle contrast imager. Seventeen T1D patients - matched with 17 subjects according to age, gender, Body-Mass-Index, and smoking status - underwent macro- and microvascular investigations. The LH early peak assessed the transient receptor potential vanilloid type 1 channels (TRPV1) mediated vasodilation, whereas the plateau assessed the Nitirc-Oxyde (NO) and endothelium-derived hyperpolarizing factor (EDHF) pathways. PORH explored sensory nerves and (EDHF), while CIV assessed sensory nerves (C-fibers) and prostaglandin-mediated vasodilation. Using neurological investigations, we observed that C-fiber and A-delta fiber functions in T1D patients were similar to control subjects. PORH, CIV, LH peak and plateau vasodilations were significantly decreased in T1D patients compared to controls, whereas there was no difference between the two groups for ACh and SNP vasodilations. Neurovascular microcirculatory vasodilations (C-fibers and TRPV 1-mediated vasodilations) are impaired in TD1 patients whereas no abnormalities were found using clinical neurological investigations. Clinicaltrials: No. NCT02538120. [ABSTRACT FROM AUTHOR]

Metal-matrix composites are produced from Al powder and 30 vol% of icosahedral Al-Cu-Fe quasi-crystalline particles using a hot isostatic pressing technique. It is demonstrated that the initial icosahedral phase is transformed into the ?-Al70Cu20Fe10 tetragonal phase during the hot isostatic pressing (HIP) process. The mechanical properties of the composite were evaluated over the temperature range 293 to 773 K by performing compression tests at constant strain rate. The temperature dependence of the yield stress gives evidence of two temperature regimes with a transition temperature at approximately 423 K. Strain-rate sensitivity measurements support the change in rate-controlling deformation mechanisms at this temperature. It is proposed that cross-slip and/or climb mechanism control plastic flow. Finally, it is suggested that the phase transformation of the particle contributes positively to the improvement of the mechanical properties. [ABSTRACT FROM AUTHOR]

TiCx-Al2O3 composites have been synthesized by pressure-assisted combustion synthesis of (Ti + C + Al2O3) reactant powder. Different alumina contents (10-40 vol%) have been investigated to study the dilution effect on TiC microstructure. A mechanical method and a mixed chemical/mechanical method have been used to obtain (Ti + C + Al2O3) powder mixtures with different alumina distributions. Scanning electron microscopy (SEM) observations of these mixtures show that alumina is distributed inside micrometric (Ti + C) aggregates for the first method whereas alumina is located around (Ti + C) aggregates for the second one. X-ray diffraction (XRD) and SEM analyses of the composites indicate that TiCx is substoichiometric in carbon and mainly consists of submicrometric grains. A distribution of Al2O3 inside (Ti + C) aggregates is more efficient to reduce TiC grain size. For the 40 vol% Al2O3 diluted (Ti + C) mixture prepared from the mechanical route, TiCx nanocrystallites have been successfully stabilized, which demonstrates that the addition of Al2O3 diluent in a (Ti + C) mixture can be efficiently used to inhibit grain growth. [ABSTRACT FROM AUTHOR]

Objectives: To examine the relationship between the combination of alcohol and benzodiazepines and the risk of committing an unsafe driver action., Methods: We used data from the Fatality Analysis Reporting System (1993-2006) on drivers aged 20 or older who were tested for both alcohol and drugs. Using a case-control design, we compared drivers who had at least one unsafe driver action (UDA; e.g., weaving) recorded in relation to the crash (cases) to drivers who did not (controls)., Results: Drivers who tested positive for intermediate- and long-acting benzodiazepines in combination with alcohol had significantly greater odds of a UDA compared to those under the influence of alcohol alone, up to blood alcohol concentrations (BACs) of 0.08 and 0.05 g/100 ml, respectively. The odds of a UDA with short-acting benzodiazepines combined with alcohol were no different than for alcohol alone., Conclusions: This study demonstrates that the combination of alcohol and benzodiazepines can have detrimental effects on driving beyond those of alcohol alone. By describing these combined effects in terms of BAC equivalencies, this study also allows for the extrapolation of simple, concrete concepts that communicate risk to the average benzodiazepine user.

Background: Cannabis is known to have detrimental effects on human performance and may also affect driving adversely. However, studies designed to examine this issue have provided equivocal findings. We set up this study to further determine the effect of cannabis on driving., Methods: We used a cross-sectional, case-control design with drivers aged 20-49 who were involved in a fatal crash in the United States from 1993 to 2003; drivers were included if they had been tested for the presence of cannabis and had a confirmed blood alcohol concentration of zero. Cases were drivers who had at least one potentially unsafe driving action recorded in relation to the crash (e.g., speeding); controls were drivers who had no such driving action recorded. We calculated the crude and adjusted odds ratios (ORs) of any potentially unsafe driving action in drivers who tested positive for cannabis but negative for alcohol consumption. In computing for the adjusted OR, we controlled for age, sex, and prior driving record., Results: Five percent of drivers tested positive for cannabis. The crude OR of a potentially unsafe action was 1.39 (99% CI = 1.21-1.59) for drivers who tested positive for cannabis. Even after controlling for age, sex, and prior driving record, the presence of cannabis remained associated with a higher risk of a potentially unsafe driving action (1.29, 99% CI = 1.11-1.50)., Conclusion: Cannabis had a negative effect on driving, as would be predicted from human performance studies. This finding supports the need for interventions to decrease the prevalence of driving under the influence of cannabis, and indicates that further studies should be conducted to investigate the dose-response relationship between cannabis and safe driving.