Numerical simulations and experimental results of the deployment of thin-walled bistable composite booms

For advanced space missions, meeting the concurrent requirements of increasing payload size while minimizing spacecraft volume can be achieved through the utilization of deployable structures. In a previous study, we conducted a characterization of a thin/walled boom in terms of its interaction between attitude and elastic dynamics when fully deployed. In this current work, we have developed a numerical model to analyze the critical phase of the deployment process. We compared the model's predictions with theoretical expectations and experimental data, and found a strong agreement between them. Additionally, we investigated the effects of bistability on the deployment process by conducting experiments on both a bistable and a monostable boom. Lastly, we performed deployment tests on a free-floating platform, which emulates a small satellite, to quantitatively measure the attitude perturbations caused by the rapid deployment of the boom

DNA wrapping around MWNTs and graphene: a SERS study

In recent years, carbon nanostructure as nanotubes (CNTs) and graphene are at the centre of a significant research effort due to the strong scientific and technological interest because of their unique physical and chemical properties: large surface area, excellent thermal and electric conductivity, high electron transfer kinetics and strong mechanical strength. Recently, a great attention has been paid to the interaction of DNA with carbon-based nanostructures such as C60, multiwalled-nanotubes (MWNTs), single-walled nanotubes (SWNTs) and graphene. The development of these studies is motivated by a wide spectrum of possible use of these materials e.g. as biosensors, drug delivery agents and diagnosis tools. In this work, we applied surface-enhanced Raman spectroscopy (SERS) to the study of DNA/MWNTs and DNA/graphene systems

HUBUNGAN ANTARA FAKTOR KONSTRUKSI DAN JARAK SUMUR GALI TERHADAP SUMBER PENCEMAR DENGAN TOTAL COLIFORM AIR SUMUR GALI DI KELURAHAN MOTTO KECAMATAN LEMBEH UTARA

Sumur gali merupakan sarana air bersih yang digunakan oleh masyarakat Kelurahan Motto Kecamatan Lembeh Utara. Untuk itu perlu diperhatikan bagian konstruksi dan jarak sumur gali terhadap sumber pencemar dikarenakan dapat mempengaruhi kualitas dari air sumur yang berpotensi menyebabkan penyakit. Penelitian ini menggunakan metode observasional – analitik dengan pendekatan cross sectional. Pengambilan data diperoleh melalui observasi, pengukuran dengan menggunakan instrument penelitian berupa meteran dan lembar checklist. Jumlah sampel dalam penelitian ini yaitu 42 sampel. Total Coliform air sumur diperiksa melalui laboratrium, total coliform sesuai persyaratan Permenkes 32 Tahun 2017. Tujuan penelitian yaitu mengetahui adanya hubungan antara faktor konstruksi dan jarak sumur gali terhadap sumber pencemar dengan total coliform air sumur gali. Berdasarkan 42 sumur gali yang diobservasi bagian konstruksi yang tidak memenuhi syarat diantaranya 37 sumur dan yang memenuhi syarat hanya 7 sumur. Jarak sumur gali terhadap sumber pencemar yang tidak memenuhi syarat sebanyak 25 sumur lainnya memenuhi syarat. Berdasarkan uji total coliform dari 42 sumur diantaraya 30 sumur tidak memenuhi syarat dan 12 lainnya memenuhi syarat. Juga terdapat hubungan konstruksi sumur gali dengan total coliform dengan p-value 0,014 dan terdapat hubungan jarak sumur gali terhadap sumber pencemar dengan total coliform p-value 0,000. Dari penelitian tersebut disimpulkan adanya hubungan antara faktor konstruksi dan jarak sumur gali terhadap sumber pencemar dengan total coliform air sumur gali.Kata Kunci : Konstruksi Sumur Gali, Jarak Sumber Pencemar, Total ColiformABSTRACTDig wells is the water supply used by the Village Motto Sub Lembeh North. To be noted that section construction and the distance of the well dig against polluters due to sources can affect the quality of the well water that could potentially cause disease. This research use analytic observational methods – with cross sectional approach. Retrieval of data obtained through observation, measurement by using either a research instrument and meter sheet checklist. The number of samples in this study is 42 samples. Total Coliform water well checked through laboratrium, total coliform according the requirements of the Permenkes 32 Year 2017. The aim of the research is determine the correlation between the construction factor and the distance of the well dig against sources of polluters with total coliform dig water wells. Based on the observed to dig wells 42 part construction that unqualified include 37 wells and qualified only 7 wells. The distance of the well dig toward the source of the polluters unqualified as many as 25 other well qualified. Based on the total coliform test of 42, 30 wells which were unqualified and the other 12 are qualified. There are also correlation of construction the well dig with total coliform with p-value 0.014 and dig wells distance correlation towards the source of the contaminant with total coliform p-value 0.000. Of this research concluded the existence of relationships between the factors of construction and distance of the well dig against sources of polluters with total coliform dig water wells.Keywords: Dig Wells Construction, Distance Source Polluters, Total Colifor

RIFT process analysis for the production of green composites in flax fibers and bio-based epoxy resin

In this work, a dual objective is carried out on composite materials in flax fiber and bio-based epoxy resin: to determine the process parameters and to develop a numerical model for highlighting the potential of and the limits in the production of “green” laminates through a RIFT process (Resin Infusion under Flexible Tool). For these reasons, compressibility tests were performed in order to evaluate the behavior of commercial flax woven under the vacuum bag. Subsequently, permeability tests were performed in order to evaluate the permeability curves necessary for the numerical study of the infusion process. For the numerical analyses, the commercial software PAM-RTM was adopted and validated. In this work, vaseline oil was used as the injected resin for the validation, and a bio-based epoxy commercial system was used for the study of the infusion process in a simple case study. The results were compared with a petroleum-based epoxy system typically used for infusion processes, showing the potentiality and the critical use of bio-based resins for infusion processes

Modeling of Moisture Diffusion in Carbon Braided Composites

In this study, we develop a methodology based on finite element analysis to predict the weight gain of carbon braided composite materials exposed to moisture. The analysis was based on the analogy between thermal conduction and diffusion processes, which allowed for a commercial code for finite element analysis to be used. A detailed finite element model using a repetitive unit cell (RUC) was developed both for bundle and carbon braided composites. Conditioning tests were performed to estimate the diffusivity of both the resin and composite. When comparing numerical and experimental results, it was observed that the procedure introduces an average error of 20% and a maximum error of 31% if the RUC is assumed to be isotropic. On the other hand, the average error does not exceed 10% and the maximum error is less than 20% when the material is considered as orthotropic. The procedure is independent of the particular fiber architecture and can be extended to other composites

A NEW BRANCH of the ANIO NOVUS AQUEDUCT (ROME, ITALY) REVEALED by ARCHAEOLOGY and GEOPHYSICS

The area south-east of Rome is characterised by the presence of several roman aqueducts which brought water to the eternal city from the Apennine and Alban Hills springs. In the last 40 years, several pieces of evidence about these aqueducts were acquired during the realisation of archaeological test trenches before building activities. In 2019, a small branch of a subterranean aqueduct unknown to the Latin sources was unearthed in Via dei Sette Metri. Here we show that this aqueduct is a lateral branch of the Anio Novus, a major imperial aqueduct built between 38 and 52 CE. To achieve this result, we employed detailed photogrammetric restitution of the new aqueduct and an integrated geophysical survey focused in the area where the Anio Novus was supposed to pass. Electrical Resistivity Tomography (ERT) and Ground Penetrating Radar (GPR) methods were used to reconstruct aqueduct paths and their relative heights. Different light conditions were tested during the picture acquisition step to determine the best practice in the photogrammetric restitution. The results obtained in this study confirmed the great effectiveness of the integration between geophysical investigation methods and the modern archaeology approach in detecting buried ancient structures

SLC6A14, a Pivotal Actor on Cancer Stage: When Function Meets Structure

SLC6A14 (ATB0,+) is a sodium- and chloride-dependent neutral and dibasic amino acid transporter that regulates the distribution of amino acids across cell membranes. The transporter is overexpressed in many human cancers characterized by an increased demand for amino acids; as such, it was recently acknowledged as a novel target for cancer therapy. The knowledge on the molecular mechanism of SLC6A14 transport is still limited, but some elegant studies on related transporters report the involvement of the 12 transmembrane \u3b1-helices in the transport mechanism, and describe structural rearrangements mediated by electrostatic interactions with some pivotal gating residues. In the present work, we constructed a SLC6A14 model in outward-facing conformation via homology modeling and used molecular dynamics simulations to predict amino acid residues critical for substrate recognition and translocation. We docked the proteinogenic amino acids and other known substrates in the SLC6A14 binding site to study both gating regions and the exposed residues involved in transport. Interestingly, some of these residues correspond to those previously identified in other LeuT-fold transporters; however, we could also identify a novel relevant residue with such function. For the first time, by combined approaches of molecular docking and molecular dynamics simulations, we highlight the potential role of these residues in neutral amino acid transport. This novel information unravels new aspects of the human SLC6A14 structure-function relationship and may have important outcomes for cancer treatment through the design of novel inhibitors of SLC6A14-mediated transport

p63 isoforms regulate metabolism of cancer stem cells

p63 is an important regulator of epithelial development expressed in different variants containing (TA) or lacking (\u394N) the N-terminal transactivation domain. The different isoforms regulate stem-cell renewal and differentiation as well as cell senescence. Several studies indicate that p63 isoforms also play a role in cancer development; however, very little is known about the role played by p63 in regulating the cancer stem phenotype. Here we investigate the cellular signals regulated by TAp63 and \u394Np63 in a model of epithelial cancer stem cells. To this end, we used colon cancer stem cells, overexpressing either TAp63 or \u394Np63 isoforms, to carry out a proteomic study by chemical-labeling approach coupled to network analysis. Our results indicate that p63 is implicated in a wide range of biological processes, including metabolism. This was further investigated by a targeted strategy at both protein and metabolite levels. The overall data show that TAp63 overexpressing cells are more glycolytic-active than \u394Np63 cells, indicating that the two isoforms may regulate the key steps of glycolysis in an opposite manner. The mass-spectrometry proteomics data of the study have been deposited to the ProteomeXchange Consortium (http://proteomecentral. proteomexchange.org) via the PRIDE partner repository with data set identifiers PXD000769 and PXD000768

Point-of-care vaccinators' perceptions of vaccine hesitancy drivers: A qualitative study from the cape metropolitan district, South Africa.

BACKGROUND: Vaccination coverage remains suboptimal in many parts of the world, especially in low-and middle-income countries (LMICs), including South Africa. Vaccine hesitancy, a recognized factor contributing to low vaccination uptake in many parts of the world, is suspect in the suboptimal vaccination coverage level in South Africa, particularly in the Western Cape Province. We aimed to investigate vaccine hesitancy and to describe point-of-care vaccinators' perceptions of the drivers of vaccine hesitancy in the Cape Metropolitan District, South Africa (Cape Metro). We conducted in-depth interviews with 19 point-of-care vaccinators in 16 purposively selected healthcare facilities in the Cape Metro between September and November 2019. Participants were sampled purposively as 'rich cases' who had been delivering vaccination services for at least five years post-qualification. We organized the data thematically in ATLAS.ti and report findings thematically by the types of reasons participants reported for vaccine hesitancy amongst clients. FINDINGS: Of the 19 interviewees, 11 (59%) reported having encountered vaccine-hesitant clients at some point in their careers. Reasons reported for vaccine hesitancy by clients included: (a) religion, (b) internet misinformation, (c) concern over causing the child pain, (d) natural immunity development, and (e) concern about possible adverse effect following immunization. Vaccine hesitancy in the Cape Metro cuts across all socio-economic classes. Also, some communities perceived to be vaccine-hesitant were mentioned by the participants in this study. CONCLUSIONS: Attitude towards vaccination are generally positive in the Cape Metro. However, vaccine hesitancy is present. The issues of vaccine hesitancy at the reported levels can still be mitigated by continuous health education in the clinics and communities, as well as stakeholder engagement as suggested by the point-of-care vaccinators in the Cape Metro