Systematic solution for multi-model control approaches in nonlinear dynamic systems based on the s-gap metric.

This paper proposes a systematic approach for optimizing the distribution of local models in multi-model control systems (MMCS) to enhance overall robustness. While existing literature discusses this method for linear parameter varying (LPV) and uncertain linear time-invariant (LTI) systems, significant limitations persist in addressing nonlinear dynamic systems. Robust control tools like the gap metric and generalized stability margin (GSM) have limited effectiveness in analyzing the robustness of nonlinear feedback systems. To address these challenges, novel concepts of the gap metric and GSM are introduced to determine central operating points (COPs) within local operating areas (LOAs) across the total operating area (TOA). These COPs guide the extraction of affine disturbance local models (ADLMs). Additionally, an optimization problem based on the s-gap metric and GSM is presented to optimize COPs placement and LOAs boundaries. Challenges such as non-monotonic behavior of the cost function and complexity arising from the s-gap metric formulation necessitate novel solution methods. To address these, constraints are applied to the cost function, and a novel discrete optimization approach is introduced. Finally, theoretical findings are applied to the Duffing system, pH neutralization process, and continuous stirred tank reactor (CSTR) plant to evaluate the proposed method's effectiveness. This comprehensive validation across different systems underscores the versatility and practical utility of the proposed approach.

Bilateral Superior Gluteal Artery Perforator (SGAP) Flap: Modified Concept in Perineal Reconstruction.

Background/Objectives: Perineal reconstruction after abdominoperineal excision often requires complex closures and is fraught with wound healing complications. Flap-based approaches introduce non-irradiated vascularized tissue to the area of resection to fill a large soft-tissue defect and dead space, reduce the risk of infection, and facilitate wound healing. Employing perforator flaps with their beneficial donor site properties, the authors have developed a concept of bilateral superior gluteal artery perforator (SGAP) flaps to restore extensive perineal defects. Methods: This retrospective case series was conducted between September 2015 and December 2019. We included three patients who received bilateral SGAP flap reconstruction after oncological resection. One deepithelialized SGAP flap was used for obliteration of dead space, combined with the contralateral SGAP flap for superficial defect reconstruction and wound closure. Results: Within this patient population, two male and one female patient, with a median age of 62 years (range, 52-76 years), were included. Six pedicled SGAP flaps were performed with average flap dimensions of 9 × 20 cm (range 7-9 × 19 × 21). No flap loss or no local recurrence were documented. In one case, partial tip necrosis with prolonged serous drainage was observed, which was managed by surgical debridement. No further complications were detected. Conclusions: The combination of two SGAP flaps provides maximal soft tissue for defect reconstruction and obliteration of dead space, while maintaining a very inconspicuous donor site, even with bilateral harvesting. Given these advantages, the authors recommend this promising approach for successful reconstruction of perineal defects.

Microsurgical Breast Reconstruction: Maximizing Success.

Breast reconstruction is becoming increasingly recognized as a fundamental component in comprehensive breast cancer treatment. The primary goal for any reconstruction is to safely restore a natural appearing breast. When it comes to achieving the elements of size, shape, symmetry, and softness, the use of autologous tissue has many advantages. The approach to autologous breast reconstruction has changed substantially over the years as microsurgical free tissue transplants become more routine and accessible. While a variety of flap donor sites exist, careful flap selection based on surgical history and the availability of donor tissue is critical in achieving reliable results. This article reviews the clinical considerations in patient evaluation, donor site selection, and surgical approach taken at the Buncke Clinic.

Multidisciplinary Treatment of Persistent Nontuberculous Mycobacterial Spinal Hardware Infection with a Pedicled Superior Gluteal Artery Perforator Flap.

Nontuberculous mycobacterial hardware infections are extremely challenging to treat. Multidisciplinary care involving removal of infected hardware, thorough debridement, and durable soft tissue coverage in conjunction with antibiotic therapy is essential for successful management. This case report presents a patient with chronic mycobacterial spinal hardware infection that underwent successful treatment with aggressive serial debridements and reconstruction with a large pedicled superior gluteal artery perforator flap coverage.

Safety and Efficacy of the Superior Gluteal Artery Perforator (SGAP) Flap in Autologous Breast Reconstruction: Systematic Review and Meta-Analysis.

(1) Background: The superior gluteal artery perforator (SGAP) flap is a prominent technique for autologous breast reconstruction. Unlike other commonly used techniques, current literature on the safety and efficacy of the SGAP flap is heterogenous and limited. The aim of this article was to perform a systematic literature review and meta-analysis of postoperative outcomes and complications associated with SGAP flap autologous breast reconstructions. (2) Methods: A systematic literature search of multiple databases was performed using the PRISMA guidelines. We included articles evaluating SGAP flaps in autologous breast reconstruction. Outcomes and complications were recorded and analyzed. Proportions and their 95% confidence intervals (CIs) were calculated in a random-effects meta-analysis. (3) Results: Fourteen studies meeting inclusion criteria, representing a total of 667 SGAP flaps, were included. The total flap loss rate was 1% (95% CI 0-3%), partial flap loss rate was 1% (95% CI 0-3%), hematoma rate was 3% (95% CI 1-6%), emergent surgical re-exploration rate was 5% (95% CI 2-9%), and overall donor-site complications were 12% (95% CI 4-23%). (4) Conclusions: This systematic review and meta-analysis provide comprehensive knowledge on the efficacy and safety of the SGAP flap in autologous breast reconstruction. It demonstrates its overall safety and low complication rate, validating its important role as an effective option in breast reconstruction.

Three Diverse Granule Preparation Methods for Proteomic Analysis of Mature Rice (Oryza sativa L.) Starch Grain.

Starch is the primary form of reserve carbohydrate storage in plants. Rice (Oryza sativa L.) is a monocot whose reserve starch is organized into compounded structures within the amyloplast, rather than a simple starch grain (SG). The mechanism governing the assembly of the compound SG from polyhedral granules in apposition, however, remains unknown. To further characterize the proteome associated with these compounded structures, three distinct methods of starch granule preparation (dispersion, microsieve, and flotation) were performed. Phase separation of peptides (aqueous trypsin-shaving and isopropanol solubilization of residual peptides) isolated starch granule-associated proteins (SGAPs) from the distal proteome of the amyloplast and the proximal 'amylome' (the amyloplastic proteome), respectively. The term 'distal proteome' refers to SGAPs loosely tethered to the amyloplast, ones that can be rapidly proteolyzed, while proximal SGAPs are those found closer to the remnant amyloplast membrane fragments, perhaps embedded therein-ones that need isopropanol solvent to be removed from the mature organelle surface. These two rice starch-associated peptide samples were analyzed using nano-liquid chromatography-tandem mass spectrometry (Nano-HPLC-MS/MS). Known and novel proteins, as well as septum-like structure (SLS) proteins, in the mature rice SG were found. Data mining and gene ontology software were used to categorize these putative plastoskeletal components as a variety of structural elements, including actins, tubulins, tubulin-like proteins, and cementitious elements such as reticulata related-like (RER) proteins, tegument proteins, and lectins. Delineating the plastoskeletal proteome begins by understanding how each starch granule isolation procedure affects observed cytoplasmic and plastid proteins. The three methods described herein show how the technique used to isolate SGs differentially impacts the subsequent proteomic analysis and results obtained. It can thus be concluded that future investigations must make judicious decisions regarding the methodology used in extracting proteomic information from the compound starch granules being assessed, since different methods are shown to yield contrasting results herein. Data are available via ProteomeXchange with identifier PXD032314.

Removal of starch granule associated proteins alters the physicochemical properties of annealed rice starches.

The effect of removal of starch granule associated proteins (SGAPs), annealing and dual-treatment on physicochemical properties of three rice starches with different amylose content (AC) was investigated. SGAPs removal reduced stability of starch granules, thus increasing amylose leaching, swelling power, solubility, and pseudoplasticity of Qiuguang (15.6% AC) and Luhui (22.1% AC) rice starches, decreasing pseudoplasticity of Yangfunuo (1.56% AC) starch, and decreasing To, Tp, and Tc, pasting viscosity and storage modulus of all three rice starches. Annealing decreased amylose leaching of the three starches, and pasting properties, pseudoplastic and storage modulus of Yangfunuo starch, but increased swelling power of the three starches, ΔH and To of Qiuguang starch, and pasting properties and pseudoplasticity of Qiuguang and Luhui starches. The effect of dual-treatment was generally the sum of effect of SGAPs removal and annealing treatment. But an interaction effect of the dual-treatment was observed for some parameters. The effect of annealing was closely related to the variety and composition of the starch.

The evolution of autologous breast reconstruction.

With breast cancer (BC) becoming more treatable, breast reconstruction has become an integral part of BC treatment. Nowadays, implant-based breast reconstruction is more common. However, there is a growing interest in autologous breast reconstruction due to the increasing awareness of implant-related complications. This work provides a comprehensive overview of the evolution of autologous reconstruction techniques of the breast and the nipple-areolar complex (NAC).

Microsurgical Tissue Transfer in Breast Reconstruction.

Autologous breast reconstructions have grown in popularity because of their durability, aesthetic outcomes, symmetry, increase in external beam radiotherapy use, and potential aesthetic enhancement at the donor site. Increasing patient expectations for predictable high aesthetic outcomes with minimal complications or need for further procedures has been met by refinement in the use of flaps. The authors' microsurgical breast reconstruction center aims to provide this while delivering efficient service. The deep inferior epigastric flaps form 85% and transverse upper gracilis and profunda artery perforator flaps account for 10%; lumbar artery perforator flaps are a new addition to the authors' armamentarium.

Breast reconstruction with Superior Gluteal Artery Perforator free flap: 8 years of experience.

INTRODUCTION: The SGAP flap represents an alternative for autologous breast reconstruction when DIEP is not available. In this article, we report eight years of experience in breast reconstruction using SGAP free flap and discuss our results, how our procedures have evolved, the outcomes and complications rates and how to perform this procedure efficiently while managing the challenges inherent to this type of flap. MATERIALS AND METHODS: A retrospective study was conducted from June 2009 and June 2017. Patients requiring SGAP flap breast reconstruction were enrolled. Donor site availability was categorised into 4 classes according to the availability of tissue. An ad hoc outcome scale was created to standardise the results and ensure data comparability. RESULTS: A total of 119 patients were enrolled in the study. We recorded 18 cases of excellent results, 57 good, 30 moderate and 14 poor. Our results show that donor site class impacts complications and patient outcome. The odds ratio analysis demonstrated that the third class donor site has a protective impact on complications and has a direct correlation with good patient outcomes. CONCLUSIONS: SGAP flap can provide very good outcomes, and it should be considered as another option when DIEP is not available. Patient selection and efficiency are the keys to achieve optimal results and minimise complications. Although this flap is available for patients with a low BMI, the donor site has to provide enough tissue to achieve symmetry with the contralateral breast and allow a tension-free closure without contour deformity.

[A giant sacral chordoma resection and reconstruction with a gluteal perforator flap, a case report and literature review]. / Chordome géant du sacrum et reconstruction par lambeau perforant glutéal supérieur, à propos d'un cas clinique et revue de la littérature.

BACKGROUND: Sacral chordomas are rare primary bone tumors and represent more than half of all primary malignant sacral tumors. Surgical resection is the only treatment with close to 50% of remission at 10 years, with or without radiotherapy. This tissue removal can be very extensive and morbid, particularly for evolved tumors. The reconstruction mostly uses myocutaneous flaps, notably the gluteus maximus flap and the latissimus dorsi flap, increasing morbidity of the surgical procedure. To avoid a muscular sacrifice and reduce the post-surgical morbidity, we describe the case of a patient who underwent a giant sacral chordoma resection and a reconstruction with a superior gluteal artery perforator flap. CASE REPORT: A 57-y.o. patient with a voluminous sacral chordoma had undergone a partial sacrectomy and abdomino-perineal resection. Firstly, a laparoscopy was realized to create a colostomy, to dissect an omental flap and to prepare the monobloc resection. In a prone position, the resection of the tumor was achieved and a de-epithelialized superior gluteal artery perforator flap was performed to fill the space and to support pelvic organs. CONCLUSION: For resections of sacral chordomas, coelioscopy has considerably reduced the surgical morbidity. However, the majority of reconstructions use myocutaneous flaps, specifically gluteus maximus and latissimus dorsi, which their postural function is considerable. Muscular sacrifice can lead to functional impotence with difficulty walking and standing up and run contrary to the diminution morbidity initiated by oncologic surgeons.

Salvage mastectomy for local recurrence and second ipsilateral autologous breast reconstruction using a perforator flap from a different donor site.

Only one case of second ipsilateral autologous reconstruction for the same breast that had previously undergone reconstruction has been reported. Here we present a patient who underwent breast reconstruction twice using free flap from different donor sites, using a buttock after a local recurrence following the previous reconstruction with a lower abdomen.

Microsurgical Tissue Transfer in Breast Reconstruction.

Autologous breast reconstructions have grown in popularity because of their durability, aesthetic outcomes, symmetry, increase in external beam radiotherapy use, and potential aesthetic enhancement at the donor site. Increasing patient expectations for predictable high aesthetic outcomes with minimal complications or need for further procedures has been met by refinement in the use of flaps. The authors' microsurgical breast reconstruction center aims to provide this while delivering efficient service. The deep inferior epigastric flaps form 85% and transverse upper gracilis and profunda artery perforator flaps account for 10%; lumbar artery perforator flaps are a new addition to the authors' armamentarium.

Long-term follow-up of superior gluteal artery perforator flap closure of large myelomeningoceles.

OBJECTIVE Large myelomeningocele defects and poor surrounding tissue quality make some defects particularly difficult to close primarily. This paper describes the superior gluteal artery perforator (SGAP) flap technique for defect closure and long-term clinical outcomes. METHODS The technique for closing a myelomeningocele with an SGAP flap is described. A retrospective chart review was performed on a cohort of 11 patients who underwent closure in this manner. RESULTS Between 1999 and 2015, 271 myelomeningoceles were closed, 11 of which were SGAP flap closures. The mean defect size was 5.5 × 7.2 cm. All patients underwent ventriculoperitoneal shunting. There were no cases of CSF infection. Five patients had minor wound issues (small dehiscence or eschar formation) that healed satisfactorily. Two patients had soft-tissue wound infections and required multiple revisions; one patient had multiple severe developmental abnormalities, and the other patient's flap had healed with a thick underlying fat pad 4 months postoperatively. No patients had significant surgical site pain on long-term follow-up. CONCLUSIONS The SGAP flap technique achieves tension-free closure with vascularized, fat-bearing full-thickness skin. It is useful for closure of large, complex defects, is not associated with chronic pain, and carries a morbidity risk that is comparable to other complex myelomeningocele closure techniques.

Autologous flap breast reconstruction: Surgical algorithm and patient selection.

Whole breast reconstruction using autologous tissue is the gold standard in many regions of the world. Reasons include breast replacement with native skin and fat, ability to shape and mold the tissue into a breast, no foreign materials are necessary, and it lasts forever when successful. There are now many options for autologous breast reconstruction and the decision making process regarding which flap to choose will depend on ones experience and comfort, ability to perform microvascular surgery, and the milieu in which one operates. This chapter will review many of the options for autologous breast reconstruction and provide an algorithmic approach for flap and patient selection. J. Surg. Oncol. 2016;113:865-874. © 2016 Wiley Periodicals, Inc.

Colgajo de perforantes de la arteria glútea superior para reconstrucción de defecto en región lumbosacra: reporte de un caso / Superior gluteal artery perforator (SGAP) flap for lumbosacral reconstruction

Los defectos de tejidos blandos a nivel de región lumbosacra son comunes en la cirugía reconstructiva. El colgajo de perforantes de la arteria glútea superior (SGAP) es una herramienta muy útil para el cubrimiento de este tipo de defectos y se asocia con un menor porcentaje de efectos funcionales secundarios al respetar el músculo glúteo mayor y su inervación. El objetivo de este artículo es realizar el reporte de un caso describiendo las indicaciones, la técnica quirúrgica y el resultado postoperatorio de esta intervención en un paciente con un defecto de cubrimiento a nivel lumbosacro secundario a una resección oncológica.

The soft tissue defects at the level of lumbosacral region are common in reconstructive surgery. Superior gluteal artery (SGAP) perforator flap is a very useful tool for covering such defects and is associated with a lower percentage of secondary functional effects as regards the gluteus maximus muscle and its innervation. The objective of this paper is report a case, describing the indications, surgical technique, and postoperative outcome of this intervention in a patient with a soft tissue defect in lumbosacral region secondary to an oncological resection.

Risk reducing mastectomy, breast reconstruction and patient satisfaction in Norwegian BRCA1/2 mutation carriers.

The aim of this study was to evaluate the outcome of risk-reducing mastectomy in BRCA1/2 mutation carriers with and without breast cancer. Uptake, methods of operation and reconstruction, complications, patient satisfaction and histopathological findings were registered at all five departments of genetics in Norway. Data from 267 affected and unaffected BRCA1/2 mutation carriers were analyzed, including a study-specific questionnaire returned by 178 mutation carriers. There was a steady increase in the uptake of risk-reducing mastectomies during the study period. Complications were observed in 106/266 (39.7%) women. Patient satisfaction was high. The majority of women expressed great relief after risk-reducing mastectomy and would have chosen the same option again.

[Preoperative computed tomographic angiography and perforator flaps: a standardization of the protocol]. / Angiotomodensitométrie préopératoire dans les lambeaux perforants: standardisation du protocole.

INTRODUCTION: Perforator flaps have an increasing role in reconstructive surgery. The preoperative analysis of perforator arteries enables the precise identification of their caliber and course, and so to select the optimal one(s), in order to improve the flap's design therefore reducing operating time. This study aims to propose a standardized protocol of computed tomographic angiography (CTA) before DIEAP flap, ALT flap, TAP flap and SGAP flap. MATERIALS AND METHODS: This study focuses on CTA before conducting a perforator flap. Together with radiologists, a CTA protocol has been developed. It specifies the patient's positioning, the intravenous contrast's concentration, flow rate, acquisition start and slice thickness as well as techniques used for mapping and 3D reconstruction. RESULTS: Patient positioning must be the same as the operating positioning during acquisition. His skin should be free of any cloth, clothing or bandages. The intravenous contrast must have a concentration between 350 and 400mg/ml for a flow rate of 4 ml/sec and its injection followed by a rinçure with 30 ml of saline water. The region of interest (ROI) should be defined for each flap. Its definition makes it to follow the contrast's progression through it. Acquisition begins when the contrast bolus arrives at the ROI. Slice thickness should be of 0.625 mm. CONCLUSION: CTA gives information on the caliber and the septal or intramuscular course of perforator as well as on its source vessel. By making a mapping of perforators, it prepares surgical procedure and dissection. The CTA protocol enhances reliability of perforator flaps.