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The aim of this work was to optimize the sintering process of Tm-doped calcium fluoride in order to maximize the thermoluminescent (TL) response and the optically stimulated luminescence response when stimulated by visible light in the infrared (IRSL) and blue (BSL) regions. The samples were prepared by liquid phase synthesis. X-ray diffraction confirmed the formation of the characteristic calcium fluoride phase. In order to optimize the sintering process, response surface methodology (RSM) was applied separately to the three luminescence responses (TL, IRSL, and BSL). The results showed that this technique is an invaluable tool for optimizing the sintering process and that it is possible to approximate a predictive mathematical model that can estimate the luminescent area as a function of sintering temperature and time.

ABSTRACTPlasma nitriding is a thermochemical treatment to improve the surface properties of metallic materials, such as mechanical and tribological properties. The aim of this study is to compare the nitriding performance of conventional plasma nitriding (CPN) and cathodic cage plasma nitriding (CCPN) for AISI M2 tool steel at various temperatures (400°C, 450°C and 500°C). The forming tool is also processed in identical conditions, and its productivity performance in the manufacturing of nails for civil construction is also evaluated. The highest hardness is achieved while processing samples at 400°C, and better productivity performance while treating samples at 500°C, both in CPN and CCPN. Notably, the hardness and productivity performance achieved in this study, particularly using CCPN is significantly higher than the forming tool provided by the factory in which conventional processing techniques were used, and thus it suggests the effectiveness of CCPN in wide-scale industrial applications in forming tools.

Plasma nitriding is a thermochemical treatment to improve the surface properties of metallic materials, such as mechanical and tribological properties. The aim of this study is to compare the nitriding performance of conventional plasma nitriding (CPN) and cathodic cage plasma nitriding (CCPN) for AISI M2 tool steel at various temperatures (400°C, 450°C and 500°C). The forming tool is also processed in identical conditions, and its productivity performance in the manufacturing of nails for civil construction is also evaluated. The highest hardness is achieved while processing samples at 400°C, and better productivity performance while treating samples at 500°C, both in CPN and CCPN. Notably, the hardness and productivity performance achieved in this study, particularly using CCPN is significantly higher than the forming tool provided by the factory in which conventional processing techniques were used, and thus it suggests the effectiveness of CCPN in wide-scale industrial applications in forming tools.

La acalasia es el trastorno motor primario más frecuente del esófago. El estándar de tratamiento actual es la miotomía de Heller laparoscópica. En los últimos años, el desarrollo de técnicas endoscópicas avanzadas ha permitido el posicionamiento de la técnica POEM (del inglés: per-oral endoscopic myotomy) como una nueva alternativa terapéutica con resultados promisorios.

In this paper we present thermoreflectance measurements on polycrystalline silicon conducting tracks for several wavelengths of the probe beam. Two distinct experimental setup were employed, namely, the CCD camera setup and the focused laser setup. It is shown that the thermoreflectance signal behavior is closely related to the derivative of the optical reflectance with respect to the wavelength.

•Infrared spectroscopy is applied for document dating and forgery identification•Artificial and natural aged documents were compared using multivariate analysis•Advanced preprocessing methods were employed to improve models for age estimation•Infrared captured many variations related to paper brands and storage conditions•Age estimation by infrared and chemometrics is still complex for forensic use

Arterial spin labeling (ASL) is a non-invasive MRI technique that allows the quantitative measurement of perfusion, (regional cerebral blood flow (rCBF)). The ASL techniques use the labeling of the blood, by inverting or saturating the spins of water molecules of the blood supplying the imaged region. When reaching the capillary bed, these will be exchanged with tissue water giving rise to a perfusion-weighted signal. The subtraction of control (without label) from labeled images yields a signal difference that directly reflects the local perfusion. Being a non-invasive method, it can be repeated as many times as needed allowing the brain perfusion variation quantification associated with endogenous and exogenous stimuli. In this study, the authors have evaluated the CBF variation induced by the neural activity during a common motor task. The study was conducted on a Siemens Verio 3T system using a 12-channel head coil and a pulsed ASL Q2TIPS-PICORE sequence with a GE-EPI readout. The sequences were driven in 3D PACE mode for prospective motion correction. Fifteen healthy volunteers were studied using a simple motor task consisting in sequential thumb-digit opposition. Two different functional ASL protocols were used: #1 one perfusion scan was obtained during rest and another one during an equal period of motor task (total scan time ~8 min) (TI1 = 700 ms, TI1s = 1600 ms, TI2 =1800 ms; 91 Interleaved tag and control volumes were acquired; TR/TE = 2500/25 ms and flip angle = 90°; nine contiguous axial slices of 8 mm thickness acquired in-line with the AC-PC axis, positioned from the vertex of the brain to the top of cerebellum; FOV = 256 × 256 mm2; matrix 64 × 64; gap between the labeling slab and the proximal 18.8 mm) and #2 a block design alternating five 25s periods of motor task with five 25s periods of rest (total scan time ~4 min) (TI1 = 700 ms, TI1s = 1600 ms, TI2 = 1800 ms; 101 interleaved tag and control volumes were acquired; TR/TE = 2500/11 ms and flip angle = 90°; nine contiguous axial slices of 6 mm thickness acquired in-line with the AC-PC axis, positioned from the vertex of the brain to the top of cerebellum; FOV = 256 × 256 mm2; matrix 64 × 64; gap between the labeling slab and the proximal 18.8 mm). The post-processing was performed using FSL (www.fmrib.ox.uk/fsl). The mean CBF values obtained for protocols #1 / #2 were: CBFrest = 61.0 / 69.4 ml/100g/min; CBFactivation = 104.8 / 109.9 ml/100g/min; and CBFvariation = CBFactivation - CBFrest = 43.7 / 40.5 ml/100g/min. The relative perfusion changes during activation [defined as CBFvariation / CBFrest (%)] were 73±6 % and 62±7 % (mean±SE) for protocols #1 and #2, respectively. These results show that both activation vs rest and block design functional protocols were capable to detect consistent variations in perfusion associated with a simple motor task. However, the block design has the advantages of requiring shorter acquisitions, directly comparing rest and activation conditions and allowing the acquisition of simultaneous Blood oxygenation level dependent (BOLD) contrast information, while still providing comparable results with the more conventional activation vs rest protocol. In conclusion, our results indicate that a block design ASL-BOLD protocol may be a preferable approach for the evaluation of perfusion changes to endogenous stimuli.

MicroRNAS (miRNAs) are a class of endogenously single-stranded non-coding RNA molecules that can negatively modulate the expression of target messenger RNAs by 3´ UTR base pairing. During the processing of a miRNA, a network of orchestrated molecular events provides a dynamic manner to posttranscriptionally modulate gene expression. Recent research has demonstrated that although these molecules are small, they are involved in several crucial biological functions, as well as, in a broad spectrum of human diseases. In this review, we highlighted the current knowledge on the miRNA pathway field, focusing on how the disruption of the miRNA-mediated silencing pathways could lead to the pathogenesis of neurological disorders. The potential use of miRNAs as diagnostic/prognostic markers and the possibility of reversing the effects of some miRNA polymorphisms/mutations by promising therapeutics procedures have brought new perspectives into the treatment of human pathologies.

Free machining steel, because of its high levels of sulfur, manganese, and lead, is known for its good machinability. These three residual elements, which act to guarantee easy chip formation, are not, however, acting alone to influence this steel's good machinability. It is their influence, certainly, that is best understood, but researchers have yet to adequately understand the influence of three other residual elements, chrome (Cr), nickel (Ni), and copper (Cu). The present study aimed to determine some measure of the impact of these elements on machinability. In particular their influence on the machinability of AISI 12L14 steel was investigated. Employing the design of experiment (DOE) technique, the tool life was measured for nine batches of steel, each containing, within the tolerable amount, different levels of chrome, nickel, and copper. By analysing the results with statistical tools, it was found that levels of their presence do indeed influence the machinability of AISI 12L14 steel. Therefore, even within the variability allowed by the standards, steel-makers should manage the levels of these residual elements.

In this paper we present thermoreflectance measurements on polycrystalline silicon conducting tracks for several wavelengths of the probe beam. Two distinct experimental setup were employed, namely, the CCD camera setup and the focused laser setup. It is shown that the thermoreflectance signal behavior is closely related to the derivative of the optical reflectance with respect to the wavelength.

OBJECTIVE: To report a case of psoriasiform eruption induced by infliximab.CASE SUMMARY: A 46-year-old woman with enterocutaneous fistula secondary to Crohn's disease developed pruriginous, erythematous, desquamative plaques on her elbows, knees, hands, and buttocks after receiving the second and third doses of intravenous infliximab. Histologic examination showed a lichenoid pattern. No new cutaneous lesions appeared after cessation of infliximab therapy.DISCUSSION: Several cutaneous reactions secondary to infliximab, a monoclonal antibody against tumor necrosis factor-alfa, have been described. Psoriasiform dermatitis has not been reported as a cutaneous reaction to infliximab, but there have been several previous reports of psoriasiform dermatitis secondary to other drugs. An objective causality assessment revealed that the adverse event was probable.CONCLUSIONS: This is the first report of a clinico-pathologic dissociated pattern of cutaneous reaction showing a histopathologic picture of lichenoid dermatitis resulting from infliximab treatment.

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental pollutants. Due to its structural similarity with the potent carcinogen dibenzo[a,l]pyrene (DB[a,l]P) and because of its environmental presence, dibenzo[c,mno]chrysene (naphtho[1,2-a]pyrene, N[1,2-a]P) is of considerable research interest. We therefore developed an efficient synthesis of N[1,2-a]P, and examined its in vitro metabolism by male Sprague Dawley rat liver S9 fraction. Its mutagenic activity in S. typhimurium TA 100 and its morphological cell transforming ability in mouse embryo fibroblasts were evaluated. On the basis of spectral analyses, the in vitro major metabolites were identified as the fjord region dihydrodiol trans-9,10-dihydroxy-9,10-dihydro-N[1,2-a]P (N[1,2-a]P-9,10-dihydrodiol), the K-region diols N[1,2-a]P-4,5-dihydrodiol and N[1,2-a]P-7,8-dihydrodiol, and also the 1-, 3-, and 10-hydroxy-N[1,2-a]P; the structure of N[1,2-a]P-9,10-dihydrodiol was also confirmed by independent synthesis. In assays with S. typhimurium TA 100, N[1,2-a]P-9,10-dihydrodiol was half as mutagenic as (±)-trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene (B[a]P-7,8-dihydrodiol) at ≥4 nmol/plate. N[1,2-a]P-9,10-dihydrodiol was much more mutagenic than N[1,2-a]P at all dose levels, suggesting that the N[1,2-a]P-9,10-dihydrodiol is the likely proximate mutagen of N[1,2-a]P. Evaluation of morphological cell transformation in C3H10T1/2C18 mouse embryo fibroblasts revealed that N[1,2-a]P was comparable to B[a]P. We further examined the pattern of in vitro adduct formation between calf thymus DNA and (±)-anti-9,10-dihydroxy-9,10-dihydro-11,12-epoxy-9,10,11,12-tetrahydro-N[1,2-a]P (N[1,2-a]PDE) and found that dG-adduct formation is 2.9-fold greater than dA-adduct formation. On the basis of our results and those reported in the literature, our working hypothesis is that N[1,2-a]P may be added to the list of potent carcinogens that includes DB[a,l]P. This hypothesis is currently being tested in our laboratory.

The Cretaceous-Paleocene (K-T) transition has been recorded in sedimentary carbonate rocks in northwestern Argentina and southern Chile. In the Yacoraite Basin, Argentina, this transition has been preserved in a 2 m thick marly layer, at the base of the Tunal Formation, which overlies lacustrine/marine carbonates of the Yacoraite Formation (Cabra Corral dam). The K-T transition is also preserved at Maimara, where Tertiary sandstones overlie a 50 m thick limestone bed of the Yacoraite Formation. In the Magellan Basin, Chile, glauconitic sandstones with calcitic cement and limestone concretions of the Maastrichtian Punta Rocallosa Formation are overlain by sandstones, claystones, and limestones of the Chorillo Chico Formation. The K-T transition is preserved in the lower portion of the Chorillo Chico Formation.Carbonates of the Yacoraite Formation display bulk-rock δ13C values from +1 to +2‰ PDB, with a negative incursion (-4‰ PDB) at the K-T transition. δ13C values in the Tunal Formation marls vary from -3 to -1‰ PDB. At Rocallosa Point, δ13C values in limestone strata, calcite cement, and limestone concretions vary from -4 to -33 ‰ PDB, and the lowest value in the Chorillo Chico Formation apparently marks the K-T transition. The δ18O fluctuations in the Yacoraite and Magellan carbonate rocks suggest a temperature drop at the K-T transition, followed by a temperature rise.High 87Sr/86Sr ratios (0.7140-0.7156) characterize the studied profiles of the Yacoraite Formation, documenting an important 87Sr-enriched source of Sr to the water from which these carbonates precipitated. At the Magellan basin, 87Sr/86Sr ratios are closer to the expected values for the global Late Cretaceous-Paleocene ocean.

Upper Precambrian-Lower Cambrian sequences in the Tucuman, Salta and Jujuy provinces, NW Argentina, comprise sandstone, slate, conglomerate and black limestone (Las Tienditas/Volcan Fms.) with abundant Vendian/Tommotian trace fossils in the clastic facies rocks. The Precordillera basin, San Juan province, represents a continuous carbonate sequence belonging to the Lower to Middle Cambrian La Laja Fm. The Pie-de-Palo Range, Pampean Range, characterized by carbonates intercalated with greenschist/amphibolite facies metaclastic rocks, forms a part of the Precordillera basement. The δ13C values in carbonates of the Las Tienditas Fm. show a gradual decrease from the base (+3.4 ‰PDB) to the top with a minimum of −1.6‰ observed at ∼15m from the top, the latter having a higher clay content. Carbonates in a 700m thick section within La Laja Fm. is marked by a slightly positive δ13C values at the base (marly) with a negative anomaly (−2.0‰) at ∼20 m above, followed by a small positive anomaly (+0.5‰) ∼100 m from the base. All the values above this point are around −0.5‰ with a negative anomaly (−2.0‰) recorded at ∼240m above the base.

The Web is used for many purposes in education, such as the publication of course management information, centralized distribution of course materials, and supporting on-line discussions between instructors and students or among the students themselves. Leveraging off the Web for educational activities both inside and outside the classroom produces a dynamic educational repository. In this paper, we present work that explicitly attempts to connect in-class activity, in the form of multimedia, Web-accessible captured lectures, with collaborative discussion spaces. Flexible and dynamic interfaces for the captured lectures and the discussion spaces are presented, as well as specialized interfaces that connect the two. We discuss our experience in a recent course taught using this integrated and dynamic educational repository and explain how our experience has lead to some solutions for visualizing the changes that occur over this rich space.

AbstractStudies of defined mixtures of carcinogenic polycyclic aromatic hydrocarbons (PAH) have identified three major categories of interactions: antagonism; synergism; and additivity depending on the biological model, tissue, route of exposure, and specific PAH. To understand the bases of these interactions we studied binary mixtures of benzo[a]pyrene (B[a]P) and dibenz[a,h]anthracene (DBA) in transformable C3H10T1/2C18 (C3H10T1/2) mouse embryo fibroblast cells in culture. C3H10T1/2 cells treated with binary mixtures of B[a]P and DBA gave less than additive morphological cell transformation based on response additivity. These results were consistent with those reported in mice and rats on the antagonistic effects of B[a]P and DBA on tumorigenesis. 32P-Postlabeling DNA adduct studies revealed that DBA reduced B[a]P-DNA adduct levels by 47% with no effect on DBA-DNA adduct levels. This suggests that one mechanism for the inhibition of morphological cell transformation of binary mixtures of B[a]P and DBA is due to alterations in the metabolic activation of B[a]P.

Summary We report a case of a 57-year-old woman who presented simultaneously cutaneous polyarteritis nodosa and Crohn's disease of the colon. Although similar pathogenic hypotheses have been reported, the association of both diseases is exceptional.

Sucrose phosphorylase fromLeuconostoc mesenteroideswas immobilbilized by covalent linkage to several supports, and the specific activity recovery was 2-11%. The enzyme adsorbed onto DEAE-cellulose re tained about 18% specific activity and was stable over eight months. The optimum pH (7.0) and temperature (30°C) did not change after immobilization. Also there was no improvement of thermal stability, and Km for sucrose and phosphate was lower compared to the soluble enzyme.

A Flow Injection Analysis (FIA) for sucrose using invertase (E.C. 3.2.1.26), mutarotase (E.C.5.1.3.3) and glucose oxidase (E.C.1.1.3.4) was developed. The enzymes were immobilised on glass beads using glutaraldehyde. The sucrose concentration was related to oxygen saturation. Fall in O2concentration, as a result of sucrose oxidation, was detected by a low cost, home-made O2electrode. The system was able to measure sucrose from 0.025 to 100mM with a response time of 6min using 200 μl of sample, with an apparent Km of 42mM of sucrose. The system has been operated satisfactorily for 50 days without loss any initial activity.

A lipases (glycerol ester hydrolases E. C. 3.1.1.3) from a brazilian strain ofPenicillium citrinumhas been investigated. When the microorganism was cultured in the simple medium (1.0% olive oil and 0.5% yeast extract), using olive oil in as carbon source in the inocula, the enzyme extracted showed maximum activity (409 IU/mL). In addition, decrease of yeast extract concentration also reduces the lipase activity. Nevertheless, when yeast extract was replaced by ammonium sulfate, no activity was detected. Purification by precipitation with ammonium sulfate showed best activity in the 40–60% fraction. The optimum temperature for enzyme activity was found in the range of 34–37°C. However, after 30 min at 60°C, the enzyme was completely inactivated. The enzyme showed optimum at pH 8.0. The dried concentrated fraction (after dialysis and lyophilization) maintained its lipase activity at room temperature (28°C) for 8 mo. This result in lipase stability suggests an application of lipases fromP. citrinumin detergents and other products that require a high stability at room temperature.

Summary.Nine Friesian dairy cows were treated with 2·5 μg GnRH i.v. at 2-h intervals for 48 h commencing between Days 3 and 8 post partum. Hormone concentrations were measured in jugular venous plasma. An episodic pattern of LH release was induced in all animals and there was no significant change in amplitude during treatment. However, cows treated between Days 7 and 8 ('late') showed higher LH episode peaks than did those treated between Days 3 and 6 ('early'). Plasma FSH concentrations showed a less clear episodic pattern in response to GnRH injection. The mean height of FSH responses to GnRH tended to be higher in the 'early' group than in the 'late' group, as did mean FSH concentrations during the pretreatment sampling period. Although clear episodic changes were not observed, GnRH treatment induced a rapid sustained rise in plasma oestradiol-17β concentrations, indicating the responsiveness of ovarian follicles to gonadotrophin stimulation early in the post-partum period. There was no difference in oestradiol-17β concentrations between the 'early' and 'late' groups during the treatment period. Only one cow exhibited preovulatory-type LH, FSH and oestradiol-17β surges during the 96-h post-treatment sampling period.It is concluded that: (1) responsiveness to GnRH pulses increases significantly and FSH responsiveness tends to decrease with time post partum, (2) ovarian follicles are able to secrete oestradiol-17β in response to GnRH-induced LH and FSH release during the early post-partum period and there is no time-dependent change in responsiveness; and (3) the lack of preovulatory surges, except in one cow, may reflect a temporary defect in the positive-feedback mechanism by which high concentrations of oestradiol-17β induce preovulatory gonadotrophin release.