Influence of Flap Parameters on the Aerodynamic Performance of a Wind-Turbine Airfoil

A numerical method has been used to analyze the flow field related to a NACA 0015 airfoil with and without a flap and assess the influence of the flap height and angle on the surface pressure coefficient,lift coefficient,and drag coefficient.The numerical results demonstrate that the flap can effectively improve the lift coefficient of the airfoil;however,at small attack angles,its influence is significantly reduced.When the angle of attack exceeds the critical stall angle and the flap height is 1.5%of the chord length,the influence of the flap becomes very evident.As the flap height increases,the starting point of the separation vortex gradually moves forward and generates a larger wake vortex.Optimal aerodynamic characteristics are obtained for 1.5%(of the chord length)flap height and a 45°flap angle;in this case,the separation vortex is effectively reduced.

Quantitative analysis of the morphing wing mechanism of raptors:IMMU-based motion capture system and its application on gestures of a Falco peregrinus

This paper presented a novel tinny motion capture system for measuring bird posture based on inertial and magnetic measurement units that are made up of micromachined gyroscopes, accelerometers, and magnetometers. Multiple quaternion-based extended Kalman filters were implemented to estimate the absolute orientations to achieve high accuracy.Under the guidance of ornithology experts, the extending/contracting motions and flapping cycles were recorded using the developed motion capture system, and the orientation of each bone was also analyzed. The captured flapping gesture of the Falco peregrinus is crucial to the motion database of raptors as well as the bionic design.

Nasal flap preservation in endoscopic dacryocystorhinostomy for nasolacrimal duct obstruction

AIM:To compare surgical outcomes between the conventional endoscopic dacryocystorhinostomy(DCR)and a modified endoscopic DCR for the treatment of nasolacrimal duct obstruction(NLDO),and evaluate factors associated with the surgical success rate.METHODS:Medical records of patients who underwent primary DCR surgery between January 2016 and July 2020 at the Otorhinolaryngology Department of Eye and Ear International Hospital,Lebanon were reviewed.RESULTS:The study group consisted of 50 consecutive modified endoscopic DCR and the control group consisted of 138 consecutive conventional endoscopic DCR.The success rates at 1y were 98.0%(49 out of 50)for modified DCR,significantly higher compared to 84.8%(117/138)for the conventional DCR;there was no significant difference in the success rate throughout the years in terms of both surgical techniques.The modified surgery vs traditional[adjusted odds ratio(aOR)=14.96]and having an adjunctive septoplasty surgery vs not(aOR=3.99)were significantly associated with higher odds of success.CONCLUSION:Mucosal flap preservation and apposition shows significant improvement in the surgical success rate.Moreover,there is no statistically significant difference found in terms of complication rate and mean operative time between the conventional and the modified techniques.

Impact of Blade-Flapping Vibration on Aerodynamic Characteristics of Wind Turbines under Yaw Conditions

Although the aerodynamic loading of wind turbine blades under various conditions has been widely studied,the radial distribution of load along the blade under various yaw conditions and with blade flapping phenomena is poorly understood.This study aims to investigate the effects of second-order flapwise vibration on the mean and fluctuation characteristics of the torque and axial thrust of wind turbines under yaw conditions using computational fluid dynamics(CFD).In the CFD model,the blades are segmented radially to comprehensively analyze the distribution patterns of torque,axial load,and tangential load.The following results are obtained.(i)After applying flapwise vibration,the torque and axial thrust of wind turbines decrease in relation to those of the rigid model,with significantly increased fluctuations.(ii)Flapwise vibration causes the blades to reciprocate along the axial direction,altering the local angle of attack and velocity of the blades relative to the incoming wind flow.This results in the contraction of the torque region from a circular shape to a complex“gear”shape,which is accompanied by evident oscillations.(iii)Compared to the tangential load,the axial load on the blades is more sensitive to flapwise vibration although both exhibit significantly enhanced fluctuations.This study not only reveals the impact of flapwise vibration on wind turbine blade performance,including the reduction of torque and axial thrust and increased operational fluctuations,but also clarifies the radial distribution patterns of blade aerodynamic characteristics,which is of great significance for optimizing wind turbine blade design and reducing fatigue risks.

Pedicled abdominal flap using deep inferior epigastric artery perforators for forearm reconstruction: A case report

BACKGROUND Pedicled abdominal flaps are a widely used surgical technique for forearm reconstruction in patients with soft tissue defects.However,some drawbacks include restricted flap size,partial flap loss,and donor-site morbidity.To address these concerns,we present a case of a pedicled abdominal flap using the deep inferior epigastric artery perforators(DIEP)for forearm reconstruction in a patient with a large soft tissue defect.CASE SUMMARY A 46-year-old male patient was admitted to our hospital with forearm injury caused by a pressing machine.A 15 cm×10 cm soft tissue defect with complete rupture of the ulnar side structures of the forearm was found.One week after orthopedic management of the neurovascular injury and fractures using the first stage of Masquelet technique,the patient was referred to the plastic and recon-structive surgery department for wound coverage.Surgical debridement and negative-pressure wound therapy revealed a 20 cm×15 cm soft tissue defect.A pedicle abdominal flap with the DIEP was used to cover the defect.Three weeks later,the flap was detached from the abdomen,and the abdominal defect was directly closed.Subsequently,the second stage of Masquelet technique was performed at the fracture site at week 10.Finally,all donor and recipient sites healed without complications,such as flap dehiscence,infection,hematoma,or necrosis.Fracture site osteosynthesis was achieved without complications.CONCLUSION Pedicled abdominal flap using the DIEP provides a reliable option for forearm reconstruction in patients with large soft tissue defects.

Evaluation of the versatility of perforators-enhanced rhomboid flap technique for ischial sores reconstruction

Background: Prolonged pressure on the skin known as pressure sores, can cause frequent injuries to the skin and underlying tissues. However, several prevention approaches, including non-surgical and surgical management,are available. In flap surgery for pressure sores, a variety of flap types may be used;each offers certain benefits and some incidences of complications and recurrence. This study evaluated the versatility of the perforatorenhanced rhomboid flap technique for ischial sore construction.Methods: This prospective study was conducted in the Plastic Surgery Department of Fayoum University Hospital.The perforator-enhanced rhomboid flap technique was employed in 20 patients with ischial pressure sores who failed to respond to conservative treatment. A proper history was obtained and a preoperative arterial duplex was performed to determine the site of the prominent perforators for their preservation at the base of the flap.Postoperative follow-ups and evaluations were performed.Results: The mean age of the study group was 43.7 ± 13.1, ranging from 19 to 65 years. Moreover, 80% of the participants were males while 20% were female. The main etiology of the sores was paraplegia in 45% of cases.The mean surface area of sores was 24.8 ± 6.3 cm2. In 75% of cases, the color match of the flap was rated as excellent. Similarly, 70% of the patients rated flap thickness as excellent. In 55% of the cases, the scar appearance was deemed excellent. Overall satisfaction was reported as excellent by 40% of the patients, while only 5% reported poor satisfaction. Approximately, 10% of the cases were identified with seroma, and 30% had wound dehiscence of a mean size of 1.33 ± 0.98 cm and required around 6.8 ± 1.9 weeks to heal.Conclusion: The perforator-enhanced rhomboid flap technique is a versatile method for reconstructing ischial pressure sores owing to its technical ease, short operative time, reliable vascularity, aesthetic outcome, matching skin color, and short recovery time. The main limitations include large defects with large surface areas, lack of a nearby donor site for a rhomboid flap, and scarring from prior procedures around the sore.

Adaptability of bipedicled scalp advancement flap for coverage of huge scalp defects after tumor resection

Background:Several reconstructive techniques have been used to reconstruct scalp defects.Numerous researchers have studied the utilization of bipedicled scalp advancement flaps for scalp defect coverage.In this study,we will assess the adaptability of a bipedicled scalp advancement flap for coverage of huge scalp defects after tumor resection.Methods:This study was performed at the Plastic Surgery Department,Fayoum University Hospital,on 20 patients with huge scalp tumors treated by adequate excision and reconstructed using a bipedicled scalp advancement flap from December 2021 to July 2023.Results:The study was conducted on 20 patients:16(80%)were men and 4(20%)were women presenting with large scalp tumors.The mean age was 57.4 years(33-68 years).The sites of the tumors were 10(50%)occipital,6(30%)parietal,and 4(20%)parieto-occipital.No major complications occurred postoperatively,and the bipedicled flaps survived well in all cases,with no necrosis.Conclusion:Huge scalp defects after tumor resection can be safely reconstructed with a large versatile bipedicled advancement scalp flap,either transversely or longitudinally oriented,with favorable functional results and accepted aesthetic results,apart from the alopecic area over the grafted donor site,which can be treated by tissue expansion if desired later.

Lateral circumflex femoral artery perforator flap for the reconstruction of head soft tissue defects:Cross-region venous anastomosis

Background:Owing to its unique characteristics,the lateral circumflex femoral artery perforator(LCFAP)flap is often preferred for repairing head wounds with exposed skulls.However,given the vascular distribution in the head,particularly the veins,can lead to postoperative complications such as venous congestion of the flap.The rates of vascular exploration and necrosis in these flaps are significantly higher than in other body regions.Therefore,it is crucial to identify a safe and effective method for venous anastomosis of free flaps in the head region.Methods:This retrospective case series study included 10 patients with large head soft tissue defects treated at the Burn and Plastic Surgery Department of the Affiliated Hospital of Zunyi Medical University from January 2020 to December 2022.The head defects were reconstructed using LCFAP flaps,with flap veins anastomosed to the external jugular vein in the neck,either directly or via a bridging technique.Results:Among the 10 adult patients with massive head wound defects,7(70%)were men.The patients’mean age was 53.0 years(48–59 years).The wound defects were caused by trauma in 6(60%)patients and by tumors in 4(40%)patients.Postoperatively,no significant complications occurred,and all LCFAP flap survived without necrosis.Conclusion:The descending branch of the LCFAP flap effectively repairs massive head wound defects.The venous anastomosis method for this flap is associated with a low incidence of venous complications and a high patency rate,making it a clinically valuable reference.

Non-Hodgkin's lymphoma involving chronic difficult-to-heal wounds:A case report

BACKGROUND Non-Hodgkin's lymphoma(NHL)is a malignant tumor that originates from the lymphoid tissues and can potentially affect numerous organs within the body.Among these,the skin stands out as one of the primary sites affected by NHL,often presenting with multiple extra-nodal manifestations.In this report,we present an unusual case of NHL involving chronic wounds in the lower extremities that were difficult to heal.The scars were successfully treated using radiotherapy in combination with extended excision debridement and peroneal artery perforator flap grafting,resulting in satisfactory outcomes.CASE SUMMARY A 19-year-old male patient presented with ulceration of the skin on the left calf near the ankle accompanied by purulent discharge.Subsequent pathologic biopsy confirmed a diagnosis of NHL(extranodal NK/T-cell lymphoma,nasal type).Initial treatment comprised local radiotherapy and wound care;however,the wound exhibited prolonged non-healing.Consequently,the patient underwent a series of interventions including radiotherapy,wound enlargement excision debridement,and peroneal artery perforator flap grafting.Ultimately,successful healing was achieved with favorable postoperative outcomes characterized by good texture of the flap without any signs of rupture or infection.CONCLUSION The combination of radiotherapy,wound enlargement excision debridement,and peroneal artery perforator flap grafting may present a favorable treatment modality for chronic non-healing lower leg wounds resulting from NHL.

When the Combination of a Chinese Flap and Dufourmentel Makes It Possible to Treat a Hopeless Case of Squamous Cell Carcinoma of the Upper Lip

Cancers of the lip are the leading cause of labial defects, and treatment is essentially surgical. The success of a repair is assessed by two essential criteria: The functional character of the lip (restoration of continence allowing feeding) and the aesthetic quality of the repair. However, for many patients from countries whose medical infrastructure does not allow them to undertake complex reconstructions locally, medical transfers represent their only chance of treatment. The aim of this article is to share with you an extreme clinical case of labial reconstruction, the management of which was a real challenge, using two major flaps: the free ante-brachial flap and the DUFOURMENTEL-type bi-pediculated scalp flap.

Management of Square Carcinoma of the Lower Lip Using Camille-Bernard Flap under Local Anesthesia: When Constraints Dictate Our Attitude

Introduction: Squamous cell carcinomas of the lip essentially pose a therapeutic management problem. In the West, their treatment is done under general anesthesia and follows the classic rules of oncology. In our context of exercise, we sometimes have a different attitude dictated by various constraints. Observation: 55-year-old patient with no notable history, seen in consultation for a very large ulcerative-budding lesion on the right 2/3 of the lower lip with mucocutaneous involvement without lymph node findings found on examination. Faced with this suspicious lesion and the patient’s financial difficulties, we decided to operate under local anesthesia to remove this tumor. The oncological excision was followed by immediate plasty using a Camille-Bernard flap with a good immediate aesthetic and functional result and postoperative day 7. The patient was unable to take his surgical specimen to anatomy-pathology and was lost to follow-up due to lack of financial resources. On anatomo-pathological analysis of the surgical specimen, the margins were healthy with confirmation of squamous cell carcinoma (anapathological reading made for scientific interest). Discussion: The particular mentality of certain patients and their difficult financial conditions push us to have an unconventional therapeutic attitude in oncology, but which nevertheless makes it possible to resolve certain problems that we often face. Local anesthesia is possible and realistic in cases like ours and the results can be acceptable and life-saving.

Using Mustardé Flap for Reconstruction of a Traumatic Facial Injury: Case Report

Flaps become the first option when primary closure is not possible, using them to reduce the tension in the closure, as well as improving the texture and color, which ends in having a better aesthetic outcome. The Mustardé flap is a flap used for the cheek and lower eye lid defects. We present a 26-year-old male with an avulsive wound in the right maxillary region, with no bone injuries, taken to the operative room performing a Mustardé Flap for reconstruction of the defect area. Patient completed a 7-day antibiotic regimen, using non-steroid anti-inflammatories for pain, wound cleaning and flap hydration with mineral oil, subsequently having an adequate clinical and aesthetic evolution. Conclusion: The Mustardé flap can be a useful pedicled flap for the reconstruction of full-thickness defects.

Thrust Optimization of Flapping Wing via Gradient Descent Technologies

The current work aims at employing a gradient descent algorithm for optimizing the thrust of a flapping wing. An in-house solver has been employed, along with mesh movement methodologies to capture the dynamics of flow around the airfoil. An efficient framework for implementing the coupled solver and optimization in a multicore environment has been implemented for the generation of optimized solutionsmaximizing thrust performance & computational speed.

Traumatic Lower Extremity Reconstruction in a Patient with Significant Vascular Comorbidities

Limb salvage after devastating traumatic injuries, cancer extirpation, and intrinsic disease is a complex decision-making process. Although several scoring and evaluation tools have been created to attempt to apply algorithmic decision-making to the process, thoughtful clinical decision-making remains the most important standard. When limb salvage is deemed appropriate, selection of a tissue flap for limb reconstruction is dependent on the size and location of the defect, patient comorbidities, nicotine dependence, mechanism of injury to the limb, patient lifestyle, occupation, and ambulatory status. This case involves a male trauma patient with significant comorbidities and a large lower extremity wound requiring multiple operations to attempt limb reconstruction with a rectus abdominis free flap. This patient’s complex injury and comorbidities made the risk of flap failure high, illustrating that the importance of patient- and case-specific factors cannot be overstated when planning for a limb reconstruction. This extreme resort of limb reconstruction, where limb loss is the only other option and a likely consequence of even heroic efforts, is aptly called “limb salvage”.

Sternocleidomastoid flap for reconstruction of tongue small cell carcinoma: A case report

BACKGROUND The management of tongue carcinoma is excision and radical neck dissection followed with reconstruction.This is a case report of a patient with tongue squamous cell carcinoma(SCC)who underwent the procedure with sternocleidomastoid(SCM)flap reconstruction.CASE SUMMARY A 52-year-old woman without smoking history complained tongue ulcer since 3 years ago.Based on the histopathological examination,the patient was diagnosed with T2N2M0 right tongue SCC and underwent wide excision of tumor;right mandibular;neck dissection and were reconstructed with SCM flap.CONCLUSION SCC of the tongue requires wide excision and dissection of the neck and mandible if infiltration into the surrounding lymph nodes has been found.The SCM flap reconstruction could be used post-surgery.

Surgical Reconstruction of a Large Defect after Excision of Infiltrative Squamous Cell Carcinoma in the Scalp and Occipital Region: A Case Report

Squamous cell carcinoma(SCC)of the scalp is the second most prevalent skin cancer,following basal cell carcinoma.Notably,it has the capability to infiltrate the skull,dura mater,and even brain tissue.The cornerstone of treatment is the surgical removal of the lesion,with a particular focus on the depth of invasion,which is directly correlated with recurrence rates.Post-surgical strategies may involve immediate or delayed cranial bone reconstruction and repair of scalp defects using either artificial dermis or skin grafts.In the case presented,a substantial defect necessitated more than a single flap for primary repair.Hence,a single pedicle double-island flap was designed for reconstructing the occipital area.Due to increased tension on the flap following cranial bone repair,the bone repair was temporarily deferred.Postoperative care included adjuvant chemotherapy and radiotherapy to mitigate the risk of SCC recurrence.

Unusual Anterolateral Fascio Cutaneous Tight Flap for Extremity Soft Tissue Reconstruction

Soft tissue sarcoma is rare neoplasms that affect mainly the extremities. Surgery is the mean treatment and the resection results in extensive muscle and skin loss. The anterolateral tight flap is a good option for sarcomas arising in knees, superior third of legs and the medial face of thigh. The anatomy knowledge and the multidisciplinary approach is very important for a successful reconstruction. The authors report a successful case treated with the anterolateral tight flap and a literature review.

Utility of Preoperative Positron Emission Tomography (PET) in Localizing Perforator Vessels of Anterolateral Thigh Free Flap

Objectives: The anterolateral thigh (ALT) flap is often considered the workhorse in soft tissue reconstruction of head and neck defects secondary to trauma, infection, or tumor resection. Despite its many advantages, ALT flaps have been criticized due to variability in vasculature, which may result in inadequate or non-existent perforators. This retrospective study aims to investigate the utility and validity of positron emission tomography (PET) scan to identify the location and characteristics of perforators to the ALT flap. Methods: We performed a 10-year retrospective review of ALT flaps at our institution to identify patients with preoperative PET scans available for analysis. Three reviewers (attending physician, fellow, and resident) were asked to identify the number, location, and characteristics (myocutaneous versus septocutaneous) of ALT perforators on imaging, and reviewer agreement was assessed. Results were then compared to available operative data. Results: One hundred twenty-one patients were identified who underwent ALT free flap surgery. Thirty-eight preoperative PET scans were identified for review. At least one perforator was identified in 92.1% of scans. Agreement percentages regarding the number of perforators ranged from 53% - 61% whereas agreement regarding the location of a single perforator ranged from 79% - 90%. However, reviewers did not agree regarding the type of perforator, with agreement ranging from 34% - 53%. Poor agreement was observed when compared to intraoperative data, with the number of perforators ranging from 26% - 34% and the type of perforator 11% - 24%. These findings are likely due to insufficient data available in operative reports. Conclusion: Although initial studies suggest that PET scan shows promising evidence to support the capacity to preoperatively identify ALT perforators, future prospective studies are warranted to fully validate these findings.

Two-step strategy—conjunctival flap covering surgery combined with secondary deep anterior lamellar keratoplasty for the treatment of high-risk fungal keratitis

AIM:To investigate whether the two-step strategy[conjunctival flap covering surgery(CFCS)combined with secondary deep anterior lamellar keratoplasty(DALK)]is effective for patients with high-risk fungal keratitis(FK).METHODS:In this noncomparative,retrospective case series,10 subjects(6 males,4 females)with a mean age of 56.5±7.1(range 47-72)y with high-risk FK undergone the two-step strategy were included.Reported outcome measures were healing of the corneal ulcer,recurrence of FK,reject reaction,improvement in best corrected visual acuity(BCVA)and relevant complications.RESULTS:The average diameter of corneal infiltrates was 7.50±0.39 mm,ranging from 6.94 to 8.13 mm.The mean depth of corneal infiltrates was 422.4±77.1μm,ranging from 350 to 535μm.The mean corneal thickness was 597.4±117.3μm,ranging from 458 to 851μm.Hypopyon and endothelial plaques were presented in all patients.The period between the two steps was 3.65±0.9(ranging from 3 to 5)mo.The graft diameter was 7.75±0.39 mm.At the last follow-up(average 9.25±3.39,ranging from 5.5 to 17mo),no fungal recurrence or graft rejection appeared,and all patients showed improvement of BCVA.One patient suffered from liver function impairment due to oral voriconazole for 4wk and recovered spontaneously after 1wk of drug withdrawal.CONCLUSION:The two-step strategy is safe and effective in the treatment of high-risk FK by transforming intentional therapeutic penetrating keratoplasty during acute infection to later optical DALK.It is a practical strategy,especially in areas lacking fresh donor corneas and eye bank services.

“In situ bone flap” combined with vascular pedicled mucous flap to reconstruction of skull base defect

BACKGROUND At present,neuroendoscopy technology has made rapid development,and great progress has been made in the operation of lesions in the saddle area of the skull base.However,the complications of cerebrospinal fluid and intracranial infection after the operation are still important and life-threatening complications,which may lead to poor prognosis.AIM To investigate the method of in situ bone flap combined with nasal septum mucosal flap for reconstruction of enlarged skull base defect by endonasal sphenoidal approach and to discuss its application effect.METHODS Clinical data of 24 patients undergoing transnasal sphenoidal endoscopic approach in the Department of Neurosurgery,Affiliated 2 Hospital of Nantong University from January 2019 to December 2022 were retrospectively analyzed.All patients underwent multi-layer reconstruction of skull base using in situ bone flap combined with nasal septum mucosa flap.The incidence of intraoperative and postoperative cerebrospinal fluid leakage and intracranial infection were analyzed,and the application effect and technical key points of in situ bone flap combined with nasal septum mucosa flap for skull base bone reconstruction were analyzed.RESULTS There were 5 cases of high flow cerebrospinal fluid(CSF)leakage and 7 cases of low flow CSF leakage.Postoperative cerebrospinal fluid leakage occurred in 2 patients(8.3%)and intracranial infection in 2 patients(8.3%),which were cured after strict bed rest,continuous drainage of lumbar cistern combined with antibiotic treatment,and no secondary surgical repair was required.The patients were followed up for 8 to 36 months after the operation,and no delayed cerebrospinal fluid leakage or intracranial infection occurred during the follow-up.Computed tomography reconstruction of skull base showed satisfactory reconstruction after surgery.CONCLUSION The use of in situ bone flap combined with vascular pedicled mucous flap to reconstruction of skull base defect after endonasal sphenoidal approach under neuroendoscopy has a lower incidence of cerebrospinal fluid leakage and lower complications,which has certain advantages and is worthy of clinical promotion.