Spectral optimization for weighted anisotropic problems with Robin conditions

We study a weighted eigenvalue problem with anisotropic diffusion in bounded Lipschitz domains S2 c R-N, N >= 1, under Robin boundary conditions, proving the existence of two positive principal eigenvalues lambda(+/-) respectively associated with a positive and a negative eigenfunction. Next, we analyze the minimization of lambda(+/-) with respect to the sign-changing weight, showing that the optimal eigenvalues Lambda(+/-) are equal if the domain has a center of symmetry and the optimal weights are of bang-bang type, namely piece-wise constant functions, each one taking only two values. As a consequence, the problem is equivalent to the minimization with respect to the subsets of Omega satisfying a volume constraint. Then, we completely solve the optimization problem in one dimension, in the case of homogeneous Dirichlet or Neumann conditions, showing new phenomena induced by the presence of the anisotropic diffusion. The optimization problem for lambda(+/-) naturally arises in the study of the optimal spatial arrangement of resources for a species to survive in an heterogeneous habitat.(c) 2023 Elsevier Inc. All rights reserved

Extremely rare case of unilateral gigantomastia after hormonal stimulation treated with a modified wise pattern technique: A case report

Introduction: Gigantomastia, characterized by excessive breast size (usually heavier than 2.5 kg), can result from various causes and significantly affect patients’ lives. Surgical intervention is often required, and over time, several techniques have been developed for its treatment. These techniques aim to address the functional and aesthetic concerns associated with gigantomastia, providing relief to patients and improving their quality of life. Presentation of the case: A 40-year-old primiparous housewife developed unilateral gigantomastia as a conse- quence of hormone therapy. To address this, a modified reduction mammoplasty procedure was undertaken, incorporating NAC (Nipple-Areola Complex) grafting. The reduction involved removing 3450 g of tissue, resulting in restored breast symmetry and enabling the patient to reintegrate into normal daily life. Discussion: Compared to the traditional technique, the introduction of some modifications in the design allowed for the absence of complications such as dehiscence of the scar at the intersection of the T, the failure of the nipple graft attachment, and the maintenance of a conical shape over time, enabling complete symmetrization of the two breasts. Conclusion: The use of a modified version of the Thorek technique allowed for optimal functional and aesthetic restoration even in the case of a significantly disproportionate breast compared to the contralateral one, with no complications

Discussion of “Design Considerations for High-Speed Flow in Sewer Systems”

The discussers are happy to see that sewer hydraulics merits a state-of-the-art review in the Journal of Hydraulic Engineering; the discussers thank the authors for their initiative. Troubling phenomena, such as air pulsation, abrasion, abrupt pressurization, and even geyser flow, may characterize the operation of sewer structures with fast flows. The authors proposed a summary of the design criteria to prevent the occurrence of such incidents. Structural solutions, including the realization of specific manholes as a drop structure, were also reviewed. Among other issues, flow choking should be avoided in sewer conduits and manholes because it can strongly reduce their discharge capacity. Choking more likely occurs for supercritical flows in manholes than across sewer conduits because geometric and hydraulic changes provoke flow surface singularities (shock waves)

Renewable-based load shifting system for demand response to enhance energy-economic-environmental performance of industrial enterprises

A market characterized by economic uncertainty and increased competition has led industrial enterprises to find ways to improve operational efficiency and reduce energy costs. In this context, the Demand Response (DR) has drawn ever greater attention from industries, allowing the shift of the electricity usage from their normal consumption patterns in response to changes in the price of electricity over time. This study proposes an innovative control strategy for renewable-based Load Shifting (LS) system designed on, at the same time, energy, economic, and environmental performance to realize an effective DR for industrial enterprises. The proposed techno-economic model is based on power flow management, economic indicators, such as NPV, IRR, and DPP, and associated CO2 emissions, adopting both deterministic and stochastic approaches. A realistic government incentive program framed in a potential carbon-based market is also assessed and validated. The resulting solution is obtained through a sensitivity analysis of several parameters, including the operating conditions of 15%, 20%, 30%, 35%, and 45% LS. MATLAB-Simulink simulations provide the following sizes for both storage and photovoltaic systems of 38, 68, 87, 115, 153 kWh and 18, 18, 32, 43, 61 kWp, respectively. Results show the profitability of the proposed DR, with a payback period that ranges from 6 to 10 years and within 3 years when incentives are considered. NPV and IRR range from 34,261 to 101,428 € and from 7% to 15.9%, respectively. The amount of CO2 emissions is reduced up to 47.7% for the highest LS percentage. Finally, the investigated incentive program led to CO2 prices between 18.2 and 551.9 €/tonCO2. Finally, results from the stochastic analysis show a good consistence with deterministic results

Systemic sclerosis interstitial lung disease: unmet needs and potential solutions

: Systemic sclerosis (SSc), or scleroderma, is a rare, complex, systemic autoimmune disease of unknown aetiology, characterized by high morbidity and mortality often resulting from cardiopulmonary complications such as interstitial lung disease and pulmonary arterial hypertension. Despite substantial progress in unravelling the pathways involved in the pathogenesis of SSc and the increasing number of therapeutic targets tested in clinical trials, there is still no cure for this disease, although several proposed treatments might limit the involvement of specific organs, thereby slowing the natural history of the disease. A specific focus of recent research has been to address the plethora of unmet needs regarding the global management of SSc-related interstitial lung disease, including its pathogenesis, early diagnosis, risk stratification of patients, appropriate treatment regimens and monitoring of treatment response, as well as the definition of progression and predictors of progression and mortality. More refined stratification of patients on the basis of clinical features, molecular signatures, identification of subpopulations with distinct clinical trajectories and implementation of outcome measures for future clinical trials could also improve therapeutic management strategies, helping to avoid poor outcomes related to lung involvement