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The Sky View Factor (SVF) is a critical parameter for studying the thermal environment of buildings theoretically. However, there are two main definitions of SVF, one based on the visible area ratio and the other based on the view factor. When utilizing fisheye images for SVF calculation, various issues often arise, such as conceptual confusion and algorithmic errors, significantly impeding the accurate scientific analysis of thermal environmental problems. Therefore, in this study, we employed methods such as theoretical model deduction, field analysis, and software simulation and validation to investigate the calculation methods for fisheye images with equidistant projection, equisolid angle projection, and stereographic projection. We proposed the Image Distance Ratio Transformation Method (IDRTM), a correction method for calculating the SVF of fisheye images with the three projection types and corresponding calculation formulas. Finally, two cases demonstrate the computational advantages of simplicity and high accuracy associated with the orthogonal transformation formulas applied to the three types of fisheye images. In this study, the error rates of SVF calculation using three non-orthographic fisheye images directly are all higher than 29 %. After applying IDRTM, the average error rates of the transformed IDRs of three types of fisheye images are all less than 0.58 %, and the error rates of the corrected SVF of three types of fisheye images are all less than 1 %. This study elucidates the scientific definition and algorithm of SVF and provides a scientific basis for the accurate selection of SVF calculation methods corresponding to fisheye image types. [Display omitted] • A selection method for SVF applicable to thermal environment analysis is proposed. • A correction method suitable to all types of fisheye images is provided for SVF. • The accuracy of the correction method for SVF is verified by two cases. [ABSTRACT FROM AUTHOR] more...

Die „Stammzelltherapie" ist in aller Munde; nicht nur im wissenschaftlichen Kontext, sondern auch im populärwissenschaftlichen, sodass das Interesse und auch die Hoffnungen auf Arzt- und Patientenseite groß sind. Potentiell besitzen Stammzellen ein großes Indikationsspektrum, das neben der Knorpel- auch die Meniskus- und Bandregeneration miteinschließt. Für letztere Indikationen liegen zwar präklinische und vereinzelte klinische Studien vor, jedoch werden hier einerseits sehr unterschiedliche Konzepte verfolgt und andererseits liegt eine große Heterogenität der applizierten Zellen und eine Unschärfe der Terminologie der Stammzelle vor, sodass die ersten Ergebnisse als vielversprechend eingestuft werden können, es aber noch kontrollierter Studien bedarf, bevor diese Therapien für die Meniskus- und Bandregeneration in den klinischen Alltag Einzug erhalten. Im Vergleich zu Anwendungen an den Menisken und dem Bandapparat ist die Anwendung von „Stammzellen" zur Behandlung von fokalen Knorpelschäden – wo im Vergleich zur etablierten ACT (Autologen Chondrozyten Transplantation) vergleichbare Ergebnisse gezeigt werden konnten – und der Arthrose besser untersucht und weiterverbreitet, weshalb im Folgenden auf die Injektionstherapie bei Arthrose im Detail eingegangen werden soll. Everyone is talking about "stem cell therapy"; not only in the scientific context, but also in popular science, so there is great interest and hope on the doctor and patient side. Potentially, stem cells have a wide range of indications that include not only cartilage-, but also meniscus and ligament regeneration. Although there are preclinical and isolated clinical studies for the latter indications, there are on the one hand very different concepts pursued and on the other hand there is a great heterogeneity of the applied cells and a lack of definition in the terminology of the stem cell, so that the first results can be classified as promising, but controlled studies are still required before these therapies for meniscus and ligament regeneration are introduced into everyday clinical practice. Compared to applications on the menisci and the ligamentous apparatus, the use of "stem cells" for the treatment of focal cartilage defects; where comparable results could be shown compared to the established ACI (autologous chondrocyte implantation); and osteoarthritis is better investigated and disseminated, which is why the injection therapy for osteoarthritis will be discussed in more detail below. [ABSTRACT FROM AUTHOR] more...

OBJECTIVE: Autologous fat transfer (AFT) is commonly used to treat implant palpability and prevent fibrosis and thinning in mastectomy skin flaps. A major limit to this procedure is volume retention over time, leading to the introduction of fat enrichment with stromal vascular fraction (SVF+AFT). Oncological concerns have been raised over the injection of an increased concentration of progenitors cells (ASCs) in the SVF. The aim of the study is to evaluate the long-term cancer recurrence risk of SVF+AFT cases compared to AFT, in patients undergoing Nipple Sparing Mastectomy (NSM). PATIENTS AND METHODS: A prospective study was designed to compare three groups of patients undergoing NSM followed by SVF+AFT, AFT or none (control group), after a two-stage breast reconstruction. Patients were strictly followed-up for at least 5-years from the second stage reconstructive procedure. Loco-regional and systemic recurrence rate were evaluated over time as the primary outcome. Logistic regression was used to investigate which factors were associated with recurrence events and independent variables of interest were: surgical technique, age above 50 years old, lympho-vascular invasion, oncological stage, adjuvant or neoadjuvant chemotherapy, adjuvant radiotherapy and adjuvant hormone therapy. RESULTS: 41 women were included in G1 (SVF+AFT), 64 in G2 (AFT), and 64 in G3 (control group). Loco-regional recurrence rate was 2.4% for G1, 4.7% for G2, and 1.6% for G3. Systemic recurrence was 7.3%, 3.1%, and 3.1%, respectively. Among the variables included, there were no significant risk factors influencing a recurrence event, either loco-regional or systemic. In particular, SVF+AFT (G1) did not increase the oncological recurrence. CONCLUSIONS: Our data suggest that both centrifuged and SVF-enhanced fat transfer have a similar safety level in comparison to patients who did not undergo fat grafting in breast reconstruction after NSM. [ABSTRACT FROM AUTHOR] more...

Urban form is a key factor affecting the urban heat island (UHI) which leads to increased temperatures, air pollution, and energy consumption. One commonly utilized parameter to understand the urban form is the sky view factor (SVF), which represents the proportion of the sky visible from a given location. SVF is widely used to study the thermal environment near ground. However, SVF cannot fully describe the building arrangement. Also, a lot of aerial field measurements are needed to investigate the thermal environment in air. With the development of unmanned aerial vehicle (UAV) technologies, temperature and humidity information at different heights of typical samples can be collected, while aerial photos can be shot for further analysis such as calculation of ground view factor (GVF) which represents the proportion of the ground visible from a given location and may describe more site information. This paper presents a comparison between two methods for calculations of GVF, whose values are calculated with a photographic method and a vector-based method on rhino-grasshopper platform. Meanwhile, a case study of GVF and SVF distributions in continuous 3D space are shown for later research of exploring the relationship with temperature field. [ABSTRACT FROM AUTHOR] more...

Current vascularization strategies for Tissue Engineering constructs, in particular cell sheet-based, are limited by time-consuming and expensive endothelial cell isolation and/or by the complexity of using extrinsic growth factors. Herein, we propose an alternative strategy using angiogenic cell sheets (CS) obtained from the stromal vascular fraction (SVF) of adipose tissue that can be incorporated into more complex constructs. Cells from the SVF were cultured in normoxic and hypoxic conditions for up to 8 days in the absence of extrinsic growth factors. Immunocytochemistry against CD31 and CD146 revealed spontaneous organization in capillary-like structures, more complex after hypoxic conditioning. Inhibition of HIF-1α pathway hindered capillary-like structure formation in SVF cells cultured in hypoxia, suggesting a role of HIF-1α. Moreover, hypoxic SVF cells showed a trend for increased secretion of angiogenic factors, which was reflected in increased network formation by endothelial cells cultured on matrigel using that conditioned medium. In vivo implantation of SVF CS in a mouse hind limb ischemia model revealed that hypoxia-conditioned CS led to improved restoration of blood flow. Both in vitro and in vivo data suggest that SVF CS can be used as simple and cost-efficient tools to promote functional vascularization of TE constructs. Statement of Significance Neovascularization after implantation is a major obstacle for producing clinically viable cell sheet-based tissue engineered constructs. Strategies using endothelial cells and extrinsic angiogenic growth factors are expensive and time consuming and may raise concerns of tumorigenicity. In this manuscript, we describe a simplified approach using angiogenic cell sheets fabricated from the stromal vascular fraction of adipose tissue. The strong angiogenic behavior of these cell sheets, achieved without the use of external growth factors, was further stimulated by low oxygen culture. When implanted in an in vivo model of hind limb ischemia, the angiogenic cell sheets contributed to blood flux recovery. These cell sheets can therefore be used as a straightforward tool to increase the neovascularization of cell sheet-based thick constructs. [ABSTRACT FROM AUTHOR] more...

It is very obvious that urban areas should be more liveable and well equipped for different seasons to provide sustainable urban environment for the inhabitants. SVF and RayMan Pro 2.1 model are used for the determination of comfortable conditions. Measurements were also taken from north and south side and from the middle of the pedestrian ways. Time of the measurements was decided as September 2015 and January 2016 between 12:00 and 14:00. When the measurements were made, Fish-eye photos were also taken for the calculation of SVF. This study found that the relationship between temperature and SVF is more important during the winter. [ABSTRACT FROM AUTHOR] more...

The sub-grid model, sub-grid town energy budget (STEB), is developed in order to reproduce the surface energy budget over large urban areas. The STEB evaluates the energy budget of each building belonging to a built area by employing an accurate description of the canyon geometry. The STEB is coupled with the limited area model RAMS to simulate the urban heat island over the city of Rome, Italy. The model is initialised with a suitable urban digital elevation model, accounting for nearly 360,000 buildings. The results show that the coupled system RAMS-STEB reproduces adequately the behaviour of the main meteorological quantities. [ABSTRACT FROM AUTHOR] more...

The sub-grid model, sub-grid town energy budget (STEB), is developed in order to reproduce the surface energy budget over large urban areas. The STEB evaluates the energy budget of each building belonging to a built area by employing an accurate description of the canyon geometry. The STEB is coupled with the limited area model RAMS to simulate the urban heat island over the city of Rome, Italy. The model is initialised with a suitable urban digital elevation model, accounting for nearly 360,000 buildings. The results show that the coupled system RAMS-STEB reproduces adequately the behaviour of the main meteorological quantities. [ABSTRACT FROM AUTHOR] more...

Abstract: Purpose: Changes in body composition in rheumatoid arthritis (RA), including a reduction in skeletal muscle mass and the accumulation of visceral fat, have been identified, and the interaction between immune abnormality and metabolic disorders has received much attention. The effect of a high-fat (HF) diet and the role of adipose tissue in an arthritis model were investigated. Methods: The effect of an HF diet on the histopathology of joints in murine type II collagen-induced arthritis (CIA) was evaluated. The morphology and adipokine production of adipose tissues were analyzed, and macrophages in the stromal vascular fraction (SVF) were counted by flow cytometry. Serum adipokine levels were measured by ELISA. Results: Significant exacerbation of joint destruction and aggravated pathological conditions were observed in CIA mice that were fed an HF diet. However, the boundary length of adipose tissue tended to decrease and the levels of adipokines (leptin and adiponectin) were lowered by the induction of arthritis. In HF/CIA mice, nevertheless, the production of MCP-1 in adipose tissues and the accumulation of macrophages in the SVF were significantly higher than CON/CIA group. The serum leptin/adiponectin (L/A) ratio was positively correlated with the number of macrophages in the SVF and MCP-1 production by adipose tissue, particularly in the CIA group. Conclusion: Functional alterations of adipose tissues could be originated from HF diet during developing arthritis. An abnormal activation of macrophages and an increased production of MCP-1 in adipose tissues might be both involved in joint destruction and inflammation. [Copyright &y& Elsevier] more...

Abstract: Urban parks have complex surface structure that produces an environment with specific microclimatic qualities. These qualities affect the balance of energy of the human body and are applicable to an individual’s thermal perception. They have impacts on using outdoor spaces especially in hot and arid regions. This study investigates users’ thermal comfort in an urban park in Cairo, Egypt. The investigation was carried out during the hot and cold months using subjective surveys and field measurements. The campaign consisted of a subjective survey using questions on the perception of the thermal environmental applying seven-point ASHRAE 55 thermal sensation votes (TSV) in nine different zones in the urban park. At each zone, the thermal environment parameters – air temperature, solar radiation, air relative humidity and wind speed were measured. Through these data, the values of the Physiologically Equivalent Temperature (PET) were calculated in each zone using the RayMan model. The current people clothing and metabolic rate were recorded. The results of the field measurements were compared with judgements about the thermal environment. Results demonstrate that differences in the PET index among these zones due to different sky view factors (SVF) and wind speed. Results revealed an alteration in human comfort sensation between different landscape zones. This paper suggests that the thermal requirements of visitors and qualities of the local climate should be carefully considered when designing landscapes for the future urban parks in the hot and arid regions. [Copyright &y& Elsevier] more...

This study provides a review on methods of Sky View Factor (SVF) determination and intra-urban surface geometry-air temperature relationship. Then, a software-based method of SVF estimation from a 3D database, describing urban surface elements, is applied. Finally, related investigations in Szeged and importance of the results obtained are discussed. Previous investigations were limited to only specific urban parts or some canyons and used small numbers of sites and few occasions of measurements. This study utilises a large number of areal means of SVF and temperature related to a large sample area and based on numerous measurements. Our investigation reveals a strong relationship between these variables. Thus, surface geometry is a significant determining factor of the temperature distribution if the selected scale is appropriate. Therefore, investigations of sufficient number of appropriate-sized areas, covering large parts of a city, are needed to draw well-established conclusions on the studied relationship. [ABSTRACT FROM AUTHOR] more...

Osteoarthritis is a debilitating chronic degenerative disease of cartilage joint surfaces and the knee is the weight-bearing joint most frequently plagued. Intra-articular cell therapies have recently emerged as a method to manage knee osteoarthritis. A literature search identifying all articles involving use of SVF to treat knee osteoarthritis was performed, consulting several databases. In conclusion, 24 clinical trials analysed report good to excellent clinical and radiographic results for the treatment of knee OA with the use of intraarticular administration of SVF. [ABSTRACT FROM AUTHOR] more...

Increasing air temperature in urban areas has been a global concern and is mostly attributed to the urban environment's physical changes. As a result, increased urban heat island phenomenon is often observed in cities impacting outdoor spaces' quality of life. This study investigates the factors influencing a street canyon's outdoor thermal comfort. User-perception surveys and empirical measurements using Testo 480 and Testo 870 thermal imager were carried out at selected six grid-points along 600 m long and 12 m wide Besant road, a semi-motorized commercial street in Vijayawada, Andhra Pradesh, India. Based on the thermal sensation questionnaire survey, Physiologically Equivalent Temperature (PET) for all the observation points were computed using RayMan pro. The correlation between the design control parameters identified and observed PET shows that the sky view factor (SVF) and mean radiant temperature (MRT) are major influencing factors determining the street's thermal conditions. Unlike aspect ratio, SVF showed a strong correlation with PET. The results indicate that by modifying physical parameters, significant improvement in overall outdoor comfort can be attained. Further, it was observed that the respondents' comfort sensitivity is higher in range than that of comfort standards, as the respondents showed increased tolerance to high temperatures. • Outdoor thermal comfort assessment of a street in the warm and humid climate is presented. • User-perception surveys and empirical measurements using Testo 480 and Testo 870 thermal imager were carried out. • SVF and MRT are major influencing factors in street's thermal conditions. • Comfort sensitivity exhibited by the respondents are higher. • Observed neutral temperature was in the range of 29-35οC [ABSTRACT FROM AUTHOR] more...