47 research outputs found

    Sheet metal plate design: a structured approach to product optimization in the presence of technological constraints

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    Geometrical optimization of structural components is a topic of high interest for engineers involved with design activities mainly related to mass reduction. The study described in these pages focuses on the optimization of plates subjected to bending for which stiffness is obtained by a pattern of ribs. Although stiffening by means of ribs is a well-known and old technique, the design of ribs for maximum stiffness is often based on practice and experience. Classical optimization methods such as topological, topographical and parametric optimization fail to give an efficient design with a reasonable programming effort, especially when dealing with many and complex constraints. These constraints are both technical and technological. A most promising technique to obtain optimal rib patterns was to define a set of feasible rib trajectories and then to select the subset with the most efficient combinations. The result is not unique and a method to select the optimal patterns is required. In fact, the stiffening effect increases with increasing rib length, but at a greater cost. A trade-off must be found between structural performance and cost: The tools to guide this selection process is the main objective of the paper, with particular attention in evaluating the stiffening due to the presence of beads on the plate with a close link with the production system and possible technological constraints which can occur during manufacturing processes, such as minimum rib distance or the presence of discontinuities or the presence of holes or other elements on the plate. A special tool with enforced rib cross section is considered, and optimal rib deployment has to be found. Numerical examples attached show the methodology and obtainable results. \ua9 2011 Springer-Verlag London Limited

    HIDRAdisk: validation of an innovative visual tool to assess the burden of hidradenitis suppurativa

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    Background Hidradenitis suppurativa (HS) is a chronic, relapsing, inflammatory skin disease characterized by painful inflamed nodules, recurrent abscesses and fistulas located in apocrine gland–bearing body sites. The negative impact of HS on patient's quality of life (QoL) has been reported to be greater than other dermatologic conditions as psoriasis and atopic eczema, and its improvement is an important goal in disease management. Nowadays, there are no specific validated QoL instruments available for HS and generic dermatologic questionnaires are used. Objective The objective of this study was to demonstrate the validity, reliability and responsiveness of HIDRAdisk, a new innovative tool designed for rapid assessment of HS burden and, at the same time, an intuitive graphic visualization of the measurement outcome. Methods A multicentre, longitudinal, observational study was conducted to validate the HIDRAdisk compared with other validated questionnaires [Skindex‐16, Dermatology Life Quality Index (DLQI), Work Productivity and Activity Impairment–General Health (WPAI:GH)] and to evaluate its correlation with disease severity in Italian patients with any degree of HS severity, as measured by Hurley stage and HS Physician Global Assessment (HS‐PGA). Results A total of 140 patients (59% women; mean age 34.9 ± 11.0 years) were enrolled in 27 dermatologic centres. HIDRAdisk showed a strong correlation with Skindex‐16 and DLQI, and a good one with WPAI:GH (correlation coefficient: 0.7568, 0.6651 and 0.5947, respectively) and a statistically significant correlation with both Hurley stage and HS‐PGA. Very good internal consistency (Cronbach coefficient >0.80; intraclass correlation coefficient >0.6), with correlation between the 10 items, good test–retest reliability (Spearman correlation coefficient, 0.8331; P < 0.0001) and responsiveness to changes were demonstrated. Conclusion Our study shows that HIDRAdisk, a short and innovative visual HS QoL instrument, has been psychometrically validated in Italian language and it may help improve the management of HS once implemented in routine clinical practice

    HIDRAdisk: validation of an innovative visual tool to assess the burden of hidradenitis suppurativa

    Get PDF
    Background Hidradenitis suppurativa (HS) is a chronic, relapsing, inflammatory skin disease characterized by painful inflamed nodules, recurrent abscesses and fistulas located in apocrine gland–bearing body sites. The negative impact of HS on patient's quality of life (QoL) has been reported to be greater than other dermatologic conditions as psoriasis and atopic eczema, and its improvement is an important goal in disease management. Nowadays, there are no specific validated QoL instruments available for HS and generic dermatologic questionnaires are used. Objective The objective of this study was to demonstrate the validity, reliability and responsiveness of HIDRAdisk, a new innovative tool designed for rapid assessment of HS burden and, at the same time, an intuitive graphic visualization of the measurement outcome. Methods A multicentre, longitudinal, observational study was conducted to validate the HIDRAdisk compared with other validated questionnaires [Skindex‐16, Dermatology Life Quality Index (DLQI), Work Productivity and Activity Impairment–General Health (WPAI:GH)] and to evaluate its correlation with disease severity in Italian patients with any degree of HS severity, as measured by Hurley stage and HS Physician Global Assessment (HS‐PGA). Results A total of 140 patients (59% women; mean age 34.9 ± 11.0 years) were enrolled in 27 dermatologic centres. HIDRAdisk showed a strong correlation with Skindex‐16 and DLQI, and a good one with WPAI:GH (correlation coefficient: 0.7568, 0.6651 and 0.5947, respectively) and a statistically significant correlation with both Hurley stage and HS‐PGA. Very good internal consistency (Cronbach coefficient >0.80; intraclass correlation coefficient >0.6), with correlation between the 10 items, good test–retest reliability (Spearman correlation coefficient, 0.8331; P < 0.0001) and responsiveness to changes were demonstrated. Conclusion Our study shows that HIDRAdisk, a short and innovative visual HS QoL instrument, has been psychometrically validated in Italian language and it may help improve the management of HS once implemented in routine clinical practice

    Ultrapulsed CO2 Resurfacing of Photodamaged Facial Skin in Vegan and Omnivore Patients: A\ua0Multicentric Study

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    Background and Objectives: Skin photoaging is related to extrinsic environmental exposures, mainly represented by ultraviolet radiation. One of the treatment options is laser resurfacing. As nutritional status is involved in cutaneous photodamage, we evaluated whether dietary patterns can also influence the response to facial resurfacing. Our prospective multicentric study involves three dermatologic centers specialized in laser therapy in northern Italy. The study aims to compare the outcome of a CO2 ablative laser therapy between omnivore and vegan patients. Study Design/Materials and Methods: Fifty-three omnivore and fifty-three vegan women undergoing ultrapulsed CO2 resurfacing for photodamaged facial skin were enrolled in this study. Clinical improvement was evaluated 3 and 6 months after the treatment using the modified Dover score. Results: After laser treatment, vegans showed slower complete re-epithelialization (P < 0.001*) and disappearance of the erythema (P < 0.001*). After 3 and 6 months, vegans showed worse outcomes in terms of fine lines (P < 0.001* and P < 0.001*, respectively) and tactile roughness (P = 0.003* and \u200b\u200b\u200b\u200bP = 0.002*, respectively) compared with omnivores, while they did not differ in mottled pigmentation. Conclusions: The present study suggests that diet influences the clinical outcome of fractioned CO2 laser treatment. Lasers Surg. Med. \ua9 2021 Wiley Periodicals LLC

    Fractional 1064 nm picosecond laser and skin photoaging: in vivo evaluation of treatment effects with reflectance confocal microscopy

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    Few studies showed the role of picosecond laser (PLS) in the treatment of skin photoaging signs. However, no studies have explored the microscopic effects of PSL in photoaging. The aim of this study is to preliminarily identify clinical variations induced by a 1,064 nm Nd:YAG PSL on the dĂ©colletĂ© area, then to apply the treatment protocol to treat facial photoaging and estimate the clinical and microscopic outcomes. A total of 10 consecutive patients with cutaneous photoaging were enrolled. Patients were treated 3 times at monthly intervals with the fractionated 1,064 nm Nd:YAG PSL. In a preliminary phase, PSL treatment was performed on the dĂ©colletĂ© to establish its efficacy and safety. Then, the same treatment protocol was applied to all the face and clinical and reflectance confocal microscopy (RCM) were analyzed, comparing baseline (T0) pictures and 4 months after the treatment (T1) ones. On the face, a reduction of dyschromia and wrinkles was observed at T1. Furthermore, the underlying RCM variations were revealed at different skin levels. Our results show the clinical and microscopic effectiveness and safety of the 1,064-nm Nd:YAG PSL in the treatment of skin photoaging signs

    The influence of social media on patients’ perception of aesthetic treatment outcome. Satisfaction with tattoo removal: A model

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    The level of patient satisfaction following tattoo removal often varies and frequently diverge from clinical objectivity. This study assesses how much social media can influence patient satisfaction after picosecond laser (PSL) tattoo removal, in light of the growing influence they have on consumers. Twenty-seven patients were treated with PSL for removal of professional black tattoo. Two groups of patients were identified: those who were already being treated at our institute or had been referred by other physicians (group 1) and those who found us through social media (group 2). Clinical improvement was evaluated 8 weeks after the final laser session and patients’ satisfaction was assessed. In both groups, clinical results were homogeneous; however, Group 2 patients’ subjective Global Aesthetic Improvement Scale scores were lower than those reported by clinicians (p=0.035), while Group 1 was globally more satisfied (p<0.001). We can affirm that the influence of social media on the perceptions and expectations of patients can affect their level of satisfaction. Particularly for people who are influenced by social media, it is essential to provide explanations prior to laser treatments, in order to clarify what may actually be expected from laser sources

    Picosecond Laser treatment of Striae Distensae: In vivo Evaluation of Results by 3D Analysis, Reflectance Confocal Microscopy, and Patient\u2032s Satisfaction

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    Background and Objectives: The efficacy of picosecond laser (PSL) in the treatment of striae distensae (SD) has been recently reported; otherwise, the base for this improvement has not been clarified yet. The aim of this study is to treat long-lasting SD with PLS and to describe their in vivo morphological variations after treatment using three-dimensional (3D) imaging and reflectance confocal microscopy (RCM). Study Design/Materials and Methods: A total of 27 patients asking for treatment for SD were treated with four monthly sessions of PLS. Clinical improvement was estimated through a blinded evaluation performed by two independent dermatologists, Global Assessment Improvement Scale (GAIS), patients\u2032 satisfaction, 3D imaging, and RCM assessments at baseline and 6 months after the last laser session. Results: Although a clinical improvement of SD was observed in 81.4% of patients according to physicians\u2032 GAIS, only 66.6% of patients reported subjective improvement and satisfaction after treatment (P = 0.04). 3D imaging revealed a significant improvement in terms of skin texture (P < 0.001) and mean SD depth (P < 0.001). Otherwise, RCM highlighted collagen remodeling and the appearance of new dermal papillae in all the treated SD compared with baseline. Conclusions: The present study confirms that PLS represents a safe treatment option for SD; herein, we report morphological documentation of skin variations after PLS treatment. Lasers Surg. Med. \ua9 2021 Wiley Periodicals LLC
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