Modelling corneal transparency with reference to stromal architecture

The arrangement of corneal collagen fibrils within lamellae was investigated by comparing fibril positions obtained from electron microscopy with distorted hexagonal, quasi-random and aperiodic arrays. By calculating the wavelength dependence and Fourier transforms of these various arrays it was determined that an aperiodic array based on the sunflower seed head is the most compatible with corneal ultrastructure. An investigation of corneal light scattering away from the central axis was undertaken for the first time. Experimentally it was shown that corneal transmission decreases peripherally, particularly in the far periphery near the limbus. This was shown to be theoretically compatible with calculated positional changes in refractive index and fibril radius, by calculating transmission using the direct summation of scattered fields method. In swollen human corneas, it was determined that there was a notable change in wavelength dependence in the peripheral regions, possibly suggesting an increase in the size and relative number fibril free voids. . Corneal infrared transmission is poorly studied. In this part of the spectrum, the cornea acts as an absorber of incident radiation. It was hypothesised that there should be a systematic variation between corneal hydration and infrared light transmission. Experimentally, by Fourier transform infrared spectroscopy a convenient linear relationship between hydration and transmission was found. Riboflavin-UVA crosslinking is used to treat keratoconus, a degenerative corneal disorder. A swelling experiment was performed on porcine corneas in order to elucidate whether the crosslinking mechanism is intra- or inter-fibrillar. Swelling rates for the treated and untreated tissue were not statistically significant, excluding interfibrillar crosslinking. The penetration depth of the riboflavin molecule into corneal stroma was also examined by visible spectroscopy of thin segments of tissue. It was demonstrated that when riboflavin infiltrates a full thickness cornea, the highest concentration of riboflavin is present in the anterior tissue segment.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Closing-in Behavior in Mild Cognitive Impairment: An Executive Deficit

This study explored Closing-in behavior (CIB), the tendency in figure copying to draw very close to or on top of the model, in mild cognitive impairment (MCI). The files of 154 people diagnosed with MCI were reviewed and CIB was identified in 21% of cases. Two approaches were used to explore CIB. First, we capitalized on the diverse cognitive profiles within MCI, subdividing the overall sample into people with and without memory deficits. The frequency of CIB was significantly higher in multidomain non-amnestic MCI than in multidomain amnestic MCI, suggesting that CIB is not associated with specific memory impairment. Second, we assessed the cognitive correlates of CIB, by selecting patients with MCI who completed a battery of executive, visuo-constructional and memory tasks. Sub-groups of patients with and without CIB showed a similar overall severity of cognitive decline and comparable performance in visuo-constructional and memory tasks, but those with CIB were slightly but significantly more impaired on executive function tasks. The study provides evidence against memory-based accounts of CIB, and supports recent suggestions that executive impairments are the dominant cognitive correlate of this clinical sign

Theorizing entrepreneurship: whither the context? A bibliometric analysis

Objectives In an ideal continuum between agency and structure, entrepreneurship research has largely focused on the first, while treating contexts as backdrops for venture creation. The paper aims at assessing the state of the art of the field in theorizing the co-evolution of agency and contexts in entrepreneurship processes. We do so by illustrating the results of a bibliographic analysis of the development of the literature on the interplay between entrepreneurship and contexts, and by isolating both the intellectual base of the scholarly debate and the research front –that is the recent developments of the investigation– in order to identify promising areas for empirical and theoretical analyses. In the first part of the paper we aim at uncovering the structure of the scholarly debate tackling processes and phenomena at the intersection between entrepreneurship in general and contexts. In the second part of the paper we narrow down the scope of our analysis by focusing on literature that sits at the intersection between the creation of new ventures –thus we concentrate on the emergence of new firms–, social networks and social embeddedness. The paper presents the exploratory results of a bibliometric analysis considering literature in the period 1985-2014. Prior work Recent articles by Zahra (2007) and Zahra and Wright (2011) exhort the field to factor in contexts in theory development. Zahra and Wright point to the need to develop a coherent framework on what is meant by context, the lack of which determined both the marginality of contexts in extant analyses and the heterogeneity in methods and in the operationalization of the core concepts in the current debate. Welter (2011) departs from a preoccupation with the status of contexts in recent entrepreneurship literature and provides with a systematic analysis of how contexts have been treated and analysed in major journals in the field. Welter’s exhaustive review of contexts in entrepreneurial literature shows that contexts have been often introduced as variables in empirical studies on entrepreneurship (single, discrete variables whose impact on venturing processes can be measured somehow) vis-à-vis a treatment of contexts as a lens (a broader perspective drawing attention to who, what, how and why of entrepreneurial processes). Approach The paper provides an exploratory analysis of the bibliometric structure of the debate on new venture emergence and contexts and will identify the emerging bibliometric structure of the scholarly debate. Results The article provides evidence the “empirical” nature of the current debate, wherein a majority of studies leveraged upon theories matured in other fields –sociology in particular. Moreover, it allows to appreciate how 1 the debate crossed field boundaries and became a lively conversation among diverse communities of scholars, involving researchers in organization studies, innovation, regional studies and many more. Finally, the analysis provides a preliminary overview on the structure of the debate and on the most prominent scholars animating it in the last decade. Implications The paper aims at supporting the development of overarching theoretical frameworks to increase our understanding of the interaction between contexts and new ventures in theories of entrepreneurship. It hopefully will trigger further analyses and theoretical developments. Value The value of the paper lies in the systematization of an on-going debate that is currently characterized by the multiplicity of research lines, epistemological and ontological stances, and theoretical frameworks being mobilized

<b>Trophic partitioning among three meso-predator shark species inhabiting the Northern Adriatic Sea</b>

While the general diet of Mediterranean elasmobranchs is well studied, little is known on food partitioning and competition among sympatric species, despite these being important forces structuring marine communities. Using stomach content and stable isotope analyses, we investigated diet and trophic level and evaluated diet overlap and partitioning of Scyliorhinus canicula, Mustelus mustelus, and M. punctulatus in the northern Adriatic Sea.</p

Kaposi’s Sarcoma: Evaluation of Clinical Features, Treatment Outcomes, and Prognosis in a Single-Center Retrospective Case Series

Kaposi’s sarcoma (KS) is a rare angioproliferative tumor classified in four different clinical–epidemiological forms. The diagnosis is based on histopathological and immunohistochemical analyses. The treatment is heterogeneous and includes several local and systemic therapeutic strategies. Methods: This is a retrospective cohort study including 86 KS patients treated between 1993 and 2022 at the University Hospital of Padua (AOPD) and at the Veneto Institute of Oncology (IOV). The data were extracted from an electronic database. Survival curves were generated using the Kaplan–Meier method, and Cox regression models were employed to explore associations with overall and disease-free survival. The male sex (89.53%), classical variant (43.02%), and cutaneous involvement (77.9%) were predominant. More than 61.6% of patients received a single treatment. Surgery, antiretroviral therapy, and chemotherapy were the mostly adopted approaches. A persistent response was observed in approximately 65% of patients, with a 22% relapse rate (at least 2 years). The overall survival ranges from 90 to 70% at 2 to 10 years after the diagnosis. Iatrogenic KS demonstrated a higher mortality (52.9%). This study reflects our experience in the management of KS. Comorbidities are very frequent, and treatments are heterogeneous. A multidisciplinary approach involving multiple referral specialists is essential for the appropriate management of this disease during diagnosis, treatment, and follow-up

Simultaneous Care in Oncology: A 7-Year Experience at ESMO Designated Centre at Veneto Institute of Oncology, Italy

Benefits of early palliative care referral in oncology are well-validated. At the Veneto Institute of Oncology-IRCCS, a simultaneous-care outpatient clinic (SCOC) has been active since 2014, where patients with advanced cancer are evaluated by an oncologist together with a palliative care team. We prospectively assessed SCOC patients’ characteristics and SCOC outcomes through internal procedure indicators. Data were retrieved from the SCOC prospectively maintained database. There were 753 eligible patients. The median age was 68 years; primary tumor sites were gastrointestinal (75.2%), genitourinary (15.0%) and other sites (9.8%). Predominant symptoms were psychological issues (69.4%), appetite loss (67.5%) and pain (65.9%). Dyspnea was reported in 53 patients (7%) in the referral form, while it was detected in 226 patients (34.2%) during SCOC visits (p < 0.0001). Median survival of patients after the SCOC visit was 7.3 months. Survival estimates by the referring oncologist were significantly different from the actual survival. Psychological intervention was deemed necessary and undertaken in 34.6% of patients, and nutritional support was undertaken in 37.9% of patients. Activation of palliative care services was prompted for 77.7% of patients. Out of 357 patients whose place of death is known, 69.2% died at home, in hospice or residential care. With regard to indicators’ assessment, the threshold was reached for 9 out of 11 parameters (81.8%) requested by the procedure. This study confirmed the importance of close collaboration between oncologists and palliative care teams in responding properly to cancer patients’ needs. The introduction of a procedure with indicators allowed punctual assessment of a team’s performance