Planning, creating and documenting a NASTRAN finite element model of a modern helicopter

Mathematical models based on the finite element method of structural analysis as embodied in the NASTRAN computer code are widely used by the helicopter industry to calculate static internal loads and vibration of airframe structure. The internal loads are routinely used for sizing structural members. The vibration predictions are not yet relied on during design. NASA's Langley Research Center sponsored a program to conduct an application of the finite element method with emphasis on predicting structural vibration. The Army/Boeing CH-47D helicopter was used as the modeling subject. The objective was to engender the needed trust in vibration predictions using these models and establish a body of modeling guides which would enable confident future prediction of airframe vibration as part of the regular design process

Modelatge de Pellets de Zeolita: Formulació i Procediments per Millorar les Propietats del Material com a Suport Catalític

Treballs Finals de Grau de Química, Facultat de Química, Universitat de Barcelona, Any: 2023, Tutors: Jordi Guilera Sala, Elena Martín MoralesThis study focuses on the shaping of zeolites for their application as catalyst supports for nickel-based catalysts in hydrocracking reactions. Zeolites are porous materials with high surface areas and unique structures that offer excellent catalytic properties. The shaping process involves forming zeolite particles into desired shapes to enable their application in industrial reactors and enhance their performance and stability in catalytic reactions. The effects of shaping parameters, including binder and plasticizer selection, shaping conditions, and post-treatment techniques, are investigated to achieve improved mechanical strength, porosity, and catalytic performance. A rheological study has been carried out which has shown to reduce the work of formulation. It was found that the use of a plasticizer, such as methylcellulose, is necessary to achieve good extrusion. An inorganic binder, specifically boehmite, accompanied by a peptizer like acetic acid, is used to achieve good mechanical strength. Additionally, the effects of the alkaline desilication technique and the dealumination caused by the use of acetic acid on the zeolite structure are investigated. These treatments aim to modify the zeolite framework by reducing the silica and alumina content, respectively, in order to improve diffusion properties by increasing the pore size. The resulting shaped zeolites exhibit improved mechanical strength and increased pore siz

Secretory Carcinoma of Male Breast: Case Report and Review of the Literature

Secretory carcinoma is a rare low-grade breast carcinoma, initially termed “juvenile breast cancer,” but it is now known to occur in adults of both sexes. It is the only epithelial tumor of the breast with a balanced translocation, t(12;15), that creates an ETV6-NTRK3 gene translocation. In this paper, a 19-year-old male patient has had a right breast mass for 9 years which suddenly increased in size with no evidence of palpable axillary lymph nodes. The mass was excised for frozen section and was diagnosed as malignant growth for simple mastectomy. Microscopic examination revealed the classical features of secretory carcinoma. The tumor cells were positive for EMA and S-100 protein and focally positive for cytokeratin and ER but negative for progesterone receptor, CD34, and CEA. Four months later the patient developed ipsilateral axillary lymph node enlargement, with lymph node metastases in five of the dissected 19 lymph nodes. The patient was treated with six courses of chemotherapy and radiotherapy. Conclusion. Though considered an indolent neoplasm, secretory carcinoma does metastasize to lymph nodes. Surgery in the form of mastectomy with axillary clearance is the treatment of choice. This paper includes a rare case report of secretory carcinoma in young male patient, with axillary lymph node metastasis in spite of the indolent nature that this tumor is known to display

Immunohistochemical Expression of Fibroblast Growth Factor Receptor 3 and Cyclooxygenase-2 in Urinary Bladder Carcinomas with Correlation of Schistosomiasis in Egyptian Patients

BACKGROUND: In Egypt, schistosomal infestation is a leading cause of bladder cancer. A mutation in the fibroblast growth factor receptor 3 (FGFR-3) gene is the most common and most specific genetic abnormality in bladder cancer. Similarly, cyclooxygenase-2 (COX-2) is an inducible, pro-inflammatory enzyme with previous studies showing higher expression in schistosomal-associated bladder cancer. AIM OF THE STUDY: The aim of the study was to evaluate the immunohistochemical expression of FGFR3 and COX2 in bladder carcinoma and correlates their expression to the associated schistosomal infestation to implicate possible therapeutic treatments. MATERIALS AND METHODS: This retrospective study included a total of 90 cases of archived, formalin fixed, paraffin-embedded tissue blocks that included variable subtypes and grades of urothelial carcinomas. Immunohistochemistry for expression of FGFR-3 and COX2 was performed using a standard avidin-biotin-peroxidase system. RESULTS: About 73.3% of the total cases (66 cases) showed variable positive reactivity for FGFR3, of which 33.3% (22 cases) were associated with bilharzia infection. A statistically significant correlation was detected between FGFR-3 and tumor size, grade, histologic subtype, LN status, lymphovascular invasion, and stage. About 83.3% of the total cases (75 cases) showed variable positive immunoreactivity for COX-2, of which 37.3% (28 cases) were bilharzial-associated. A positive correlation was established between COX-2 and grade, concomitant in situ changes and cases associated with bilharzia infection. CONCLUSION: FGFR-3 can be used as a prognostic marker for low-grade urothelial tumors. Results also portray that COX-2 has an inflammatory inciting role in bladder carcinoma development, especially in patients with a history of schistosomiasis (bilharziasis). Both COX-2 and FGFR-3 should be explored further for its use alone or in combination with conventional treatment, to reduce the recurrence rate and progression of superficial (low grade) tumors

“Clean” Liquid Helium

Liquid helium is the coldest fluid that exists in nature. By virtue of this fact, any unwanted substance present in liquid helium, that is, any impurity, will be “frozen” and will be in solid form. In practice, these solid impurities can be easily eliminated to obtain “optically clean” liquid. However, even “optically clean” filtered liquid helium may contain a non-negligible quantity of molecular hydrogen. These minute traces of molecular hydrogen are the causes of a known problem worldwide: the blockage of capillary tubes in helium evaporation cryostats. This problem seriously affects a wide range of cryogenic equipment used in low-temperature physics research at a considerable operational cost increase. In this chapter, we propose an underlying mechanism for this effect and provide a definitive solution by means of production of hydrogen-free liquid helium, that is, not only “optically clean” liquid helium but completely “clean” liquid helium. Moreover, basic superfluidity research studies could benefit from the availability of “clean” liquid helium

Design and intracellular trafficking of poly(L-lysine)-grafted-poly(ethylene glycol) fiberless adenoviral gene delivery vector

The first gene therapy clinical trials were started nearly 30 years ago, but the field only now seems to be on the verge of widespread adoption. Safe and efficient gene delivery, however, is still a major obstacle and is often described as "the Achilles' heel of gene therapy." Adenovirus (Ad) is the most common viral vector in gene therapy clinical trial. Adenovirus fiber and capsid proteins, however, mediate an immunogenic response and relies on interaction of the virus with the coxsackie adenovirus receptor (CAR), which limits the ability of the virus to deliver genes into CAR-negative cells such as cancer cells. Our goal was to develop a hybrid vector that overcomes Ad drawbacks as well as understand how our hybrid vector compare to the native virus in intracellular trafficking. A fiberless adenovirus (FlAd) was used with a replacement for the removed fiber protein by poly-L-lysine copolymer grafted polyethylene glycol (PLL-g-PEG). A copolymer library was synthesized using varying molecular weights of PLL and PEG with different degrees of grafting. Hybrid vectors were formed by electrostatically associating PLL-g-PEG with FlAd at different ratios, where "design of experiments" was used to optimize the approach. Hybrid vectors were evaluated by their ability to infect both CAR-positive (HEK 293) and CAR-negative (NIH 3T3) cells. To guide further development of the hybrid vector, we investigated the mechanisms of intracellular trafficking by measuring transduction efficiency and cellular uptake in the presence of a panel of drug inhibitors of various cellular pathways. PLL-g-PEG-FlAd hybrid vectors were able to transduce CAR-positive HEK 293 cells and CAR-negative NIH 3T3 cells with a 3.5- and 10.2-fold increase compared to unmodified FlAd. Addition of the PLL-g-PEG copolymer restored 85% of the infectivity of Ad in HEK 293 cells that was lost as a result of removing the fiber. In addition, hybrid vector was non-cytotoxic on both cell types and showed good serum stability up to 40%. The production of inflammatory cytokines IL-6 and TNFa was also reduced by 70% and 50%, respectively. The removal of the fibers besides the surface modification with PLL-g-PEG copolymer have modified the intracellular trafficking of the hybrid vector to affect the efficiency of the expression of the targeted gene. This stepwise transition from viral to non-viral vectors will lead to novel vectors that are both safe and highly efficient

Immunohistochemical Study of Androgen Receptor Expression in Estrogen Receptor-Negative Invasive Breast Carcinoma and its Relation with Clinicopathologic Factors

BACKGROUND: Estrogen receptor (ER)-negative breast carcinomas lack the expression of ER and they have no targeted hormone therapies. The androgen receptor (AR) is a newly emerge biomarker. Detecting AR in these tumors may provide a target for future therapies. AIM: The aim of the study is to examine the immunohistochemical expression profiles of AR protein in ER-negative invasive breast carcinomas and to assess the relation between AR expression and the clinicopathologic factors such as age, tumor size, tumor grade, tumor type, immunohistochemical type, lymph node status, and Ki67 expression. METHODS: Sixty paraffin blocks of ER-negative invasive breast carcinoma cases were stained immunohistochemically by AR. Positive expression was defined as ≥1% nuclear staining. RESULTS: AR positivity was detected in 55% of the studied cases. The positive cases were scored by H-score with a median=117, and a range of 3–285 and by Allred score with a median=7, and a range of 3-8. AR is expressed in 60.9% of triple-negative breast carcinoma cases. AR expression was higher in older age, and there were significant positive correlations between the degree of AR expression (AR%, AR intensity, and H-score) and age (p=0.050, 0.007, 0.033, respectively). There was non-significant negative correlation between Ki67% and the degree of AR expression (AR%, AR intensity, H-score, and Allred score). Regarding different histological types, tumor grade, tumor size, lymph node status, and immunohistochemical types, there was no significant difference between AR positive and AR negative cases. CONCLUSION: AR is frequently expressed in ER-negative invasive breast carcinoma; especially in older age, and in a large number of triple-negative subtypes. This may give chance to benefit from future AR target therapy. We recommend further research work on AR expression in the special histologic subtypes of ER-negative breast carcinoma and in the triple negative group

Accesibilidad y movilidad en el municipio de Aínsa-Sobrarbe. Perspectiva social y de comunicación con la Administración Local

La Administración como gestor de servicios públicos no siempre tiene la perspectiva real de las problemáticas del ciudadano. La accesibilidad y libre desplazamiento son dos elementos fundamentales para aquellos con diversidad funcional por razones de movilidad. Aínsa es uno de los municipios más bonitos de España, reconocido internacionalmente. Los gestores públicos de este pueblo deberían de adelantarse a los problemas no solo de los ciudadanos del municipio sino de aquellos turistas que deciden que Aínsa sea su lugar de vacaciones. El presente estudio tiene como finalidad valorar la percepción social, de residentes y turistas, sobre la accesibilidad y movilidad en Aínsa. Para la erradicación de las barreras existentes, las vías alternativas para solucionar el problema, la oferta de un turismo accesible, así como la propuesta de un plan de sensibilización y formación sobre el tema a la población habitante de dicha localidad. Todo ello desde una perspectiva integradora y una triangulación metodológica.<br /