Estudio del desplazamiento de una interfase líquido-gas usando el método de elementos finitos. Caso plano y axisimétrico

En este trabajo se emplea el método de elementos finitos combinado con una adecuada parametrización de la superficie libre para analizar el desplazamiento en estado estacionario de una burbuja en un líquido contenido inicialmente entre dos placas planas paralelas o en un tubo capilar de paredes rectas. Los valores obtenidos para variables, tales como el espesor de la película formada entre la burbuja y la pared del tubo, coinciden muy bien con los resultados experimentales y teóricos de la bibliografía. La técnica permite obtener soluciones en un rango muy amplio del número Capilar que incluye y extiende el rango analizado previamente en la literatura. Los resultados muestran un tipo de recirculación de flujo que no había sido descrito previamente.Peer Reviewe

Estudio del desplazamiento de una interfase líquido-gas usando el método de elementos finitos. Caso plano y axisimétrico

En este trabajo se emplea el método de elementos finitos combinado con una adecuada parametrización de la superficie libre para analizar el desplazamiento en estado estacionario de una burbuja en un líquido contenido inicialmente entre dos placas planas paralelas o en un tubo capilar de paredes rectas. Los valores obtenidos para variables, tales como el espesor de la película formada entre la burbuja y la pared del tubo, coinciden muy bien con los resultados experimentales y teóricos de la bibliografía. La técnica permite obtener soluciones en un rango muy amplio del número Capilar que incluye y extiende el rango analizado previamente en la literatura. Los resultados muestran un tipo de recirculación de flujo que no había sido descrito previamente.Peer Reviewe

Pathogenicity markers of Clostridium spp. in commercial turkeys

Since growth promoters ban in Europe, enteritis of different aetiologies (virus, bacteria and protozoa) are increasingly becoming the main cause of economic loss in commercial turkeys production. This study is focused on typing of Clostridium spp. isolated from samples of jejunum and ileum of 82 birds out of 17 turkeys flocks. The birds were 6-day to 104-day old, both male and female, with enteric disorders. The presence of toxin NetB was investigated. Multiplex PCR to detect cpa, cpb1, cpetx, cp1, cpb2 and cpe toxin genes were used for Clostridium typing. No lesions of necrotic enteritis were observed. Clostridium perfringens type A was isolated from 25 enteric samples, Clostridium difficile was found in 4 cases and Clostridium sordelli in one case. Clostridium perfringens was present from 6 to 104 days of age indicating its possible role in the enteric disorders of commercial turkeys. NetB toxin was found in no sample. 3 out of 4 isolates of Clostridium difficile were characterized by the presence of toxin genes

Liquid film drag out in the presence of molecular forces

From a practical as well as a conceptual point of view, one of the most interesting problems of physicochemical hydrodynamics is the drag out of a liquid film by a moving solid out of a pool of liquid. The basic problem, sometimes denoted the Landau-Levich problem [L. Landau and B. Levich, “Dragging of a liquid by amoving plate,” Acta Physicochim. USSR 17, 42–54 (1942)], involves an interesting blend of capillary and viscous forces plus a matching of the static solution for capillary rise with a numerical solution of the film evolution equation, neglecting gravity, on the downstream region of the flow field. The original solution describes experimental data for a wide range of Capillary numbers but fails to match results for large and very small Capillary numbers. Molecular level forces are introduced to create an augmented version of the film evolution equation to show the effect of van derWaals forces at the lower range of Capillary numbers. A closed form solution for static capillary rise, including molecular forces, was matched with a numerical solution of the augmented film evolution equation in the dynamic meniscus region. Molecular forces do not sensibly modify the static capillary rise region, since film thicknesses are larger than the range of influence of van der Waals forces, but are determinant in shaping the downstream dynamic meniscus of the very thin liquid films. As expected, a quantitatively different level of disjoining pressure for different values of molecular constants remains in the very thin liquid film far downstream. Computational results for a wide range of Capillary numbers and Hamaker constants show a clear transition towards a region where the film thickness becomes independent of the coating speed.Fil: Schmidhalter, Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química (i); ArgentinaFil: Cerro, R. L.. University of Alabama in Huntsville; Estados UnidosFil: Giavedoni, Maria Delia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química (i); ArgentinaFil: Saita, Fernando Adolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química (i); Argentin

Paclitaxel, carboplatin and gemcitabine combination as induction chemotherapy for stage IIIA N2 bulky non-small cell lung cancer

Background: Induct ion chemotherapy followed by surgical resection or definitive radiotherapy for patients affected by stage IIIA N2 bulky non-small cell lung cancer (NSCLC) has been investigated in several trials. Patients and Methods: In this present study, 52 patients with stage IIIA N2 bulky NSCLC with cytologically or histologically confirmed mediastinal lymph node involvement received paclitaxel 175 mg/mq on day 1, carboplatin AUC 5 on day 1 and gemcitabine 1,000 mg/mq on day 1 and 8 every 3 weeks for three cycles as induction chemotherapy. Results: Objective response (4 complete remission and 36 partial remission) was achieved in 40/52 patients. No early or toxic deaths were observed. Twenty-two patients were surgically explored. Fifteen were excluded for resection for biopsy-proven residual tumour in mediastinal nodes. Complete surgical resection was performed in 15 patients with confirmed pathological downstaging. Pathological complete response was achieved in 4 patients. No surgery-related mortality or significant morbidity was reported. Adjuvant radiotherapy was delivered in 15 patients, and 30 patients received definitive radiotherapy. Conclusion: In the present study, the combination of paclitaxel, carboplatin and gemcitabine has been a safe and active regimen in poor-prognosis stage IIIA N2 bulky NSCLC

Ultrafast X-ray Scattering from Molecules

We present a theoretical framework for the analysis of ultrafast X-ray scattering experiments using nonadiabatic quantum molecular dynamics simulations of photochemical dynamics. A detailed simulation of a pump-probe experiment in ethylene is used to examine the sensitivity of the scattering signal to simulation parameters. The results are robust with respect to the number of wavepackets included in the total expansion of the molecular wave function. Overall, the calculated scattering signals correlate closely with the dynamics of the molecule

Simulation of ultrafast photodynamics of pyrrole with a multiconfigurational Ehrenfest method

We report the first results of ab initio multiconfigurational Ehrenfest simulations of pyrrole photodynamics. We note that, in addition to the two intersections of 11A2 and 11B1 states with the ground state 11A1, which are known to be responsible for N–H bond fission, another intersection between the 12A2 and 12B1 states of the resulting molecular radical becomes important after the departure of the H atom. This intersection, which is effectively between the two lowest electronic states of the pyrrolyl radical, may play a significant role in explaining the branching ratio between the two states observed experimentally. The exchange of population between the two states of pyrrolyl occurs on a longer scale than that of N–H bond fission

Dyadic Profiles of Couples Coping with Body Image Concerns after Breast Cancer: Preliminary Results of a Cluster Analysis.

Breast cancer treatments have multiple adverse effects, including concerns about body appearance and function that are experienced by most patients. Altered body image negatively affects mental health, social, and relationship functioning. While the relationship with a partner is critical for patients’ psychological wellbeing and partners can promote positive body image, limited research has investigated individual and relational factors affecting the experience of both. This cross-sectional study aimed at (1) exploring rates of body image concerns among breast cancer patients, and (2) identifying dyadic profiles among participating dyads. Couples composed by patients who had undergone surgery and their romantic partners (n = 32) were recruited from the Breast Unit of a hospital in northern Italy. Both partners completed measures of personality characteristics (BFQ-2), psychological distress (HADS), coping flexibility (PACT), dyadic coping (DCQ), and closeness (IOS). Body image (BIS) and adjustment to cancer (Mini-MAC) measures were completed by patients only. K-mean cluster analyses identified 2-cluster solution among patients and partners, respectively. “Active patients” (cluster-1) reported low rates of body image concerns (p < 0.001), anxious preoccupation, negative dyadic coping, and self-oriented stress communication (p < 0.05), compared to “worried patients” (cluster-2). “Comfortable partners” (cluster-1) reported lower anxiety and depression (p < 0.001), self-oriented negative dyadic coping and closeness (p < 0.05) than “uncomfortable partners” (cluster-2). Three different dyadic profiles emerged: functional, dysfunctional, and ambivalent. Significant variations (p < 0.05) by anxiety, depression, and delegating dyadic coping existed. Results indicate there are groups of couples at greater risk for impaired psychological distress and body image concerns, which should be addressed in the context of dyadic psychosocial interventions

Oligomerization of ZFYVE27 (Protrudin) Is Necessary to Promote Neurite Extension

ZFYVE27 (Protrudin) was originally identified as an interacting partner of spastin, which is most frequently mutated in hereditary spastic paraplegia. ZFYVE27 is a novel member of FYVE family, which is implicated in the formation of neurite extensions by promoting directional membrane trafficking in neurons. Now, through a yeast two-hybrid screen, we have identified that ZFYVE27 interacts with itself and the core interaction region resides within the third hydrophobic region (HR3) of the protein. We confirmed the ZFYVE27's self-interaction in the mammalian cells by co-immunoprecipitation and co-localization studies. To decipher the oligomeric nature of ZFYVE27, we performed sucrose gradient centrifugation and showed that ZFYVE27 oligomerizes into dimer/tetramer forms. Sub-cellular fractionation and Triton X-114 membrane phase separation analysis indicated that ZFYVE27 is a peripheral membrane protein. Furthermore, ZFYVE27 also binds to phosphatidylinositol 3-phosphate lipid moiety. Interestingly, cells expressing ZFYVE27ΔHR3 failed to produce protrusions instead caused swelling of cell soma. When ZFYVE27ΔHR3 was co-expressed with wild-type ZFYVE27 (ZFYVE27WT), it exerted a dominant negative effect on ZFYVE27WT as the cells co-expressing both proteins were also unable to induce protrusions and showed cytoplasmic swelling. Altogether, it is evident that a functionally active form of oligomer is crucial for ZFYVE27 ability to promote neurite extensions