25 research outputs found
Evaluation of glue line shear strength of laminated timber structures using block and core type specimens
Monitoring and evaluation of glued laminated timber structures in service is essential to warrant its integ rity, where non-destructive techniques play an important role. This paper describes the results obtained on glued
laminated timber beams of maritime pine, with and without preservative treatment, and of spruce, exposed to natural outdoor environment as well as to artificial weathering. The assessment of glue lines’ shear strength was investigated through the extraction and testing of cores parallel and per pendicular to the glued lines and block shear specimens with 50 mm×50 mm and 20 mm×20 mm shear area. The results highlight the different performances of the various types of specimens tested, showing that the measured shear
strength depends on the specimen size and that the size effect depends on the material strength giving a decreasing modification factor with the increase of strength in opposi tion to the constant factor suggested by standard EN 14080.
They also show that shear testing of cores drilled perpen dicular to the glued joints may be a promising tool in the assessment of glulam structures on site.info:eu-repo/semantics/publishedVersio
A Comparative Study of Students’ Motivation for Learning Social Studies According to Their Preferences for Instructional Strategies at The Escola Secundária Católica De São José Operário in Dili, Timor-Leste
This research was conducted at the Escola Secundária Católica de São José Operário in Dili, Timor-Leste in the school year 2014. The purposes were: 1) to determine the level of students’ motivation for learning social studies; 2) to determine the students’ preferences among five instructional strategies; 3) to compare the students’ motivation for learning social studies according to their preferences for instructional strategies. This study used a questionnaire, including 5 motivation subscales (intrinsic goal orientation, extrinsic goal orientation, task value, control of learning beliefs, and self-efficacy for learning & performance), and 5 instructional strategies subscales (direct instruction, indirect instruction, experiential learning, independent study, and interactive instruction). The sample was 178 students in grade 10 and grade 11. The findings indicated that motivation was high overall in both grade 10 and grade 11, and that the students’ most preferred instructional strategies were direct instruction, interactive instruction and independent study. There was no significant difference between students’ motivation for learning social studies and their preferences for instructional strategies. The article concludes with recommendations for both practice and future research.
NonDestructive Techniques for the Assessment and Preservation of Historic Structures
The preservation of the built heritage has long been a public concern, mainly due
to fears about the loss of identity, history and heritage of populations. The main
concerns are the conservation and restoration of monuments that usually represent
important events in the history of a city or a country. More recently, urban residents
and policymakers have become aware of the abandonment or degradation of old city
cores, leading to mischaracterisation of the buildings and ways of living.
To preserve history and promote building and urban renewal, considering the
basic principles of the preservation process, it is important to introduce the least possible
disturbance. To start with, the diagnostic process is a key aspect, especially to
investigate the construction characteristics and the damage to materials, and to find
structural and nonstructural problems.
To start any process, a visual inspection, a study and knowledge of the original
construction methods and materials and historical repair techniques can help but
may not be sufficient, and the use of conventional techniques to complement the
information needed can result in an insufficient understanding or in extensive and
unnecessary intrusions in the construction.
In recent years, the rapid growth of science and research, combined with the
industry and the need to gather more and accurate information, have led to the fast
development of nondestructive testing methodologies that allow the architectural
archaeology to be studied, the structural assessment to be supported and information
to be given about the material properties. Each technique can be used for a specific
purpose, but, in some cases, only a combination of techniques is reliable and gives
an accurate interpretation of the data acquired.
The fundamental contribution and aim of this book is to give a full overview of several
case studies where different nondestructive techniques have been applied, in several
cases using multidisciplinary approaches, which aim to highlight the importance
of the information acquired and encourage the use of these techniques in future studies.
The book brings together 16 chapters focused on nondestructive testing techniques
applied at the urban building level and also applied to monumental buildings,
archaeology and cultural heritage, bringing together more than 40 international
researchers and experts in the field, who are the source of practical case studies supported
by a theoretical background.info:eu-repo/semantics/publishedVersio
LEVANTAMENTO E CARACTERIZAÇÃO DAS PATOLOGIAS DA CAPELA DO FUNDADOR DO MOSTEIRO DA BATALHA.
O Mosteiro de Santa Maria da Vitória, conhecido como Mosteiro da Batalha, é um dos mais belos exemplos de arquitetura em Portugal e na Europa, fazendo parte da lista do Património Mundial da UNESCO. A sua construção desenvolveu-se durante 150 anos, ao longo de diversas fases e composto por vários estilos: gótico, manuelino e renascentista. Foram feitas algumas alterações ao projeto inicial, resultando num grandioso e complexo Monástico que hoje inclui uma igreja, dois claustros com divisões anexas e dois panteões reais, a capela do fundador e as capelas imperfeitas.O património construído reúne patologias e defeitos derivados da deterioração dos materiais, cargas repetidas, falta de manutenção e eventos excecionais. Dentro deste processo, as técnicas de inspeção e diagnóstico desempenham um papel importante, fornecendo informações e permitindo a definição de medidas de reparação adequadas.Para iniciar este levantamento e caracterização das patologias foi realizado um estudo piloto sobre a Capela do Fundador, onde foi realizada uma inspeção visual detalhada e um conjunto de ensaios não destrutivos, recorrendo a termografia, ultrassons, esclerómetro e varrimento laser scanning
John Dunning’s influence in International business/strategy research: a bibliometric study in the Strategic Management Journal
In this paper we undertake a literature review analyzing John Dunning’s contribution for international business and strategy research. We examine Dunning’s articles and other works and carry out a bibliometric study in the Strategic Management Journal, in the period from 1980 to 2009, a thirty years period. We conclude that beyond the more obvious contribution to the international business discipline with the Eclectic paradigm (OLI – Ownership, Location, Internalization), Dunning’s influence extends to other theories and concepts. Specifically, we observe connections to the resource-based view, transaction costs theory, the evolutionary theory and more broadly to the theory of the multinational enterprise.info:eu-repo/semantics/publishedVersio
Acquired Vitamin B12 Deficiency in Newborns: Positive Impact on Newborn Health through Early Detection
The early diagnosis of and intervention in vitamin B12 deficiency in exclusively breastfed infants by mothers with low vitamin B12 is crucial in preventing possible irreversible neurologic damage, megaloblastic anemia, and failure to thrive. We assess the usefulness of the early detection of asymptomatic B12 deficiency related to acquired conditions and highlight the importance of monitoring serum vitamin B12 levels during pregnancy. We describe demographic, clinical, dietary, and biochemical data, including the evolution of a vitamin B12 deficiency's functional biomarkers. We enrolled 12 newborns (5 males) with an age range of 1-2 months old that were exclusively breastfed and asymptomatic. These cases were referred to our metabolic unit due to alterations in expanded newborn screening: high levels of methylmalonic acid and/or total homocysteine (tHcy). All mothers were under a vegetarian diet except three who had abnormal B12 absorption, and all presented low or borderline serum B12 level and high plasma levels of tHcy. Supplementation with oral vitB12 re-established the metabolic homeostasis of the mothers. In infants, therapy with an intramuscular injection of 1.0 mg hydroxocobalamin led to the rapid normalization of the metabolic pattern, and a healthy outcome was observed. Acquired B12 deficiency should be ruled out before proceeding in a differential diagnosis of cobalamin metabolism deficits, methylmalonic acidemia, and homocystinuria.info:eu-repo/semantics/publishedVersio
Cancer immunotherapy: nanodelivery approaches for immune cell targeting and tracking.
Cancer is one of the most common diseases afflicting people globally. New therapeutic approaches are needed due to the complexity of cancer as a disease. Many current treatments are very toxic and have modest efficacy at best. Increased understanding of tumor biology and immunology has allowed the development of specific immunotherapies with minimal toxicity. It is important to highlight the performance of monoclonal antibodies, immune adjuvants, vaccines and cell-based treatments. Although these approaches have shown varying degrees of clinical efficacy, they illustrate the potential to develop new strategies. Targeted immunotherapy is being explored to overcome the heterogeneity of malignant cells and the immune suppression induced by both the tumor and its microenvironment. Nanodelivery strategies seek to minimize systemic exposure to target therapy to malignant tissue and cells. Intracellular penetration has been examined through the use of functionalized particulates. These nano-particulate associated medicines are being developed for use in imaging, diagnostics and cancer targeting. Although nano-particulates are inherently complex medicines, the ability to confer, at least in principle, different types of functionality allows for the plausible consideration these nanodelivery strategies can be exploited for use as combination medicines. The development of targeted nanodelivery systems in which therapeutic and imaging agents are merged into a single platform is an attractive strategy. Currently, several nanoplatform-based formulations, such as polymeric nanoparticles, micelles, liposomes and dendrimers are in preclinical and clinical stages of development. Herein, nanodelivery strategies presently investigated for cancer immunotherapy, cancer targeting mechanisms and nanocarrier functionalization methods will be described. We also intend to discuss the emerging nano-based approaches suitable to be used as imaging techniques and as cancer treatment options
α-Galactosylceramide and peptide-based nano-vaccine synergistically induced a strong tumor suppressive effect in melanoma
α-Galactosylceramide (GalCer) is a glycolipid widely known as an activator of Natural killer T (NKT) cells, constituting a promising adjuvant against cancer, including melanoma. However, limited clinical outcomes have been obtained so far. This study evaluated the synergy between GalCer and major histocompatibility complex (MHC) class I and MHC class II melanoma-associated peptide antigens and the Toll-Like Receptor (TLR) ligands CpG and monophosphoryl lipid A (MPLA), which we intended to maximize following their co-delivery by a nanoparticle (NP). This is expected to improve GalCer capture by dendritic cells (DCs) and subsequent presentation to NKT cells, and simultaneously induce an anti-tumor specific T-cell mediated immunity. The combination of GalCer with melanoma peptides and TLR ligands successfully restrained tumor growth. The tumor volume in these animals was 5-fold lower than the ones presented by mice immunized with NPs not containing GalCer. However, tumor growth was controlled at similar levels by GalCer entrapped or in its soluble form, when mixed with antigens and TLR ligands. Those two groups showed an improved infiltration of T lymphocytes into the tumor, but only GalCer-loaded nano-vaccine induced a prominent and enhanced infiltration of NKT and NK cells. In addition, splenocytes of these animals secreted levels of IFN-γ and IL-4 at least 1.5-fold and 2-fold higher, respectively, than those treated with the mixture of antigens and adjuvants in solution. Overall, the combined delivery of the NKT agonist with TLR ligands and melanoma antigens via this multivalent nano-vaccine displayed a synergistic anti-tumor immune-mediated efficacy in B16F10 melanoma mouse model. STATEMENT OF SIGNIFICANCE: Combination of α-galactosylceramide (GalCer), a Natural Killer T (NKT) cell agonist, with melanoma-associated antigens presented by MHC class I (Melan-A:26) and MHC class II (gp100:44) molecules, and Toll-like Receptor (TLR) ligands (MPLA and CpG), within nanoparticle matrix induced a prominent anti-tumor immune response able to restrict melanoma growth. An enhanced infiltration of NKT and NK cells into tumor site was only achieved when the combination GalCer, antigens and TLR ligands were co-delivered by nanovaccine