319 research outputs found

    Printability study by selective laser sintering of bio-based samples obtained by using PBS as polymeric matrix

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    The emerging request to reduce the environmental impact of plastics encourages scientists to use novel sustainable polymeric materials for many applications fields. The present paper aims to use for the first-time poly (butylene succinate) (PBS), a biodegradable and compostable polymer, for Selective Laser Sintering (SLS) applications. PBS is a flexible semicrystalline aliphatic polyester, which can represent a very good alternative to the traditional thermoplastic polymers obtained by fossil sources. The present work started from a lab-scale production of PBS powders by means of an emulsion solvent evaporation/precipitation method, with the purpose to increase the number of polymeric powders available for SLS. The obtained PBS powders were first characterized by morphological and thermal point of view, and then employed as innovative polymeric material in SLS to realized 3D printed parts with increasing geometrical complexity. To confirm PBS cytocompatibility, cell proliferation and cell viability assays (MTT and Live&Dead) were measured using a lung adenocarcinoma epithelial cell line (H1299). The in vitro cytotoxicity of the 3D printed material was also investigated, showing no harm on cells

    Nb‐UVB and PUVA therapy in treating early stages of Mycosis Fungoides: A single‐center cross‐sectional study

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    IntroductionMycosis fungoides (MF) and Sezary Syndrome are the most common forms of cutaneous T-cell lymphoma. Early-stage MF is known to have an indolent behavior, and the EORTC guidelines recommend treating patients with skin-directed therapies, such as phototherapy, instead of systemic therapies. Phototherapy is a popular therapeutic option, with two commonly used light sources-PUVA and narrow band-nb UVB. PUVA is less commonly used due to its potential carcinogenic role, but it has systemic effects, while nb-UVB has mostly skin-limited effects. There is ongoing debate regarding the role of UVB light, and in 2021, the Cutaneous Lymphoma Italian Study Group reached a consensus on technical schedules for NB-UVB and PUVA for MF. This study aims to analyze and compare the efficacy of the two phototherapy options in treating early-MF patients. Materials and methodsThe study included patients diagnosed with stage IA/B MF in the last 10 years, who had at least 12 months of follow-up data and a minimum of 24 phototherapy sessions (PUVA or nb UVB) and treated with topical steroids apart from phototherapy. ResultsResults showed that the two phototherapy options were similarly effective in treating early MF, with no significant differences in clinical response, although PUVA was associated with more adverse effects. ConclusionsThe study provides valuable insights into the use of phototherapy in early MF, and the results can be used to guide treatment decisions and improve patient outcomes

    Human talar ontogeny: Insights from morphological and trabecular changes during postnatal growth

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    The study of the development of human bipedalism can provide a unique perspective on the evolution of morphology and behavior across species. To generate new knowledge of these mechanisms, we analyze changes in both internal and external morphology of the growing human talus in a sample of modern human juveniles using an innovative approach. The sample consists of high‐resolution microCT scans of 70 modern juvenile tali, aged between 8 postnatal weeks and 10 years old, from a broad chronological range from Middle/Late Neolithic, that is, between 4800 and 4500 BCE, to the 20th century. We applied geometric morphometric and whole‐bone trabecular analysis (bone volume fraction, degree of anisotropy, trabecular number, thickness, and spacing) to all specimens to identify changes in the external and internal morphology during growth. Morphometric maps were also generated. During the first year of life, the talus has an immature and globular shape, with a dense, compact, and rather isotropic trabecular architecture, with numerous trabeculae packed closely together. This pattern changes while children acquire a more mature gait, and the talus tends to have a lower bone volume fraction, a higher anisotropy, and a more mature shape. The changes in talar internal and external morphologies reflect the different loading patterns experienced during growth, gradually shifting from an “unspecialized” morphology to a more complex one, following the development of bipedal gait. Our research shows that talar plasticity, even though genetically driven, may show mechanical influences and contribute to tracking the main locomotor milestones

    An infant burial from Arma Veirana in northwestern Italy provides insights into funerary practices and female personhood in early Mesolithic Europe

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    The evolution and development of human mortuary behaviors is of enormous cultural significance. Here we report a richly-decorated young infant burial (AVH-1) from Arma Veirana (Liguria, northwestern Italy) that is directly dated to 10,211–9910 cal BP (95.4% probability), placing it within the early Holocene and therefore attributable to the early Mesolithic, a cultural period from which well-documented burials are exceedingly rare. Virtual dental histology, proteomics, and aDNA indicate that the infant was a 40–50 days old female. Associated artifacts indicate significant material and emotional investment in the child’s interment. The detailed biological profile of AVH-1 establishes the child as the earliest European near-neonate documented to be female. The Arma Veirana burial thus provides insight into sex/gender-based social status, funerary treatment, and the attribution of personhood to the youngest individuals among prehistoric hunter-gatherer groups and adds substantially to the scant data on mortuary practices from an important period in prehistory shortly following the end of the last Ice Age

    Metodi Matematici per il Recupero dei Nessi Concettuali in Uno o più Testi: Entropia e Analisi della Semantica Latente.

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    Nella prima parte si analizza il metodo dell'entropia delle parole in un testo per recuperare quelle più rilevanti in base alla distribuzione delle stesse all'interno dell'opera. Nella seconda parte viene studiata l'analisi della semantica latente e le sue basi statistiche, algebriche e analitiche. Infine vengono effettuati degli esperimenti con l'utilizzo del software InfomapNLP sulla Divina Commedia

    Morphologies in-between: The impact of the first steps on the human talus

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    Objective: The development of bipedalism is a very complex activity that contributes to shaping the anatomy of the foot. The talus, which starts ossifying in utero, may account for the developing stages from the late gestational phase onwards. Here, we explore the early development of the talus in both its internal and external morphology to broaden the knowledge of the anatomical changes that occur during early development. Materials and Methods: The sample consists of high-resolution microCT scans of 28 modern juvenile tali (from 36 prenatal weeks to 2 years), from a broad chronological range from the Late Roman period to the 20th century. We applied geometric morphometric and whole-bone trabecular analysis to investigate the early talar morphological changes. Results: In the youngest group (\u3c6 postnatal months), the immature external shell is accompanied by an isotropic internal structure, with thin and densely packed trabeculae. After the initial attempts of locomotion, bone volume fraction decreases, while anisotropy and trabecular thickness increase. These internal changes correspond to the maturation of the external shell, which is now more defined and shows the development of the articular surfaces. Discussion: The internal and external morphology of the human talus reflects the diverse load on the foot during the initial phases of the bipedal locomotion, with the youngest group potentially reflecting the lack of readiness of the human talus to bear forces and perform bipedal walking. These results highlight the link between mechanical loading and bone development in the human talus during the acquisition of bipedalism, providing new insight into the early phases of talar development
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