Site Defect Research Articles

Innovative use of radial artery retrograde forearm flap for oral and maxillofacial reconstruction

IntroductionThe purpose of this study is to present a novel method of reconstructing oral and maxillofacial defects using the Radial Artery Retrograde Proximal Forearm Flap (RARPFF) and to evaluate the efficacy and safety of the forearm flap for direct closure of the donor site and its effect on hand function in the donor area. MethodsA prospective study of 30 patients who underwent oral and maxillofacial reconstruction with RARPFF between June 2021 and April 2024 was conducted to evaluate the safety and efficacy of the flap and its influence on hand function in the donor area. ResultsFlap survival was 93.3 %. The donor site defect in 28 out of 30 patients healed primarily. All donor sites were directly closed without complications such as splitting, tendon exposure, or numbness in the thumb or thenar region. Statistically significant differences were observed in grip strength (MD = 4.56, p < 0.001) and elbow extension (MD = 2.78, p < 0.001) at 3 months, as well as in grip strength (MD = 2.20, p < 0.001) and elbow extension (MD = 1.67, p < 0.001) at 1 year, compared to the contralateral hand. Wrist flexion, extension, radial deviation, ulnar deviation, elbow flexion, pronation, and supination did not exhibit statistically significant differences from the contralateral hand at both 3 months and 1 year. The Michigan Hand Questionnaire (MHQ) revealed a statistically significant difference in aesthetics compared to the contralateral hand (p < 0.001), along with satisfactory overall hand function, activities of daily living (ADL), work performance, pain levels, and patient satisfaction with hand function. ConclusionsThe reverse radial artery proximal forearm flap is a dependable and secure technique for head and neck reconstruction. This method can effectively reduce donor site complications while preserving hand function.

Preparation of vascularized forearm dermal fat flap and repairing of donor site

Objective:This study prepared vascularized dermal fat flaps and introduced a local split-thickness skin graft from an in situ cutaneous area cutaneous area to manage forearm flap donor sites and evaluated the esthetic and functional outcomes post-operatively. From July 2020 to June 2023, 13 patients with soft tissue defects in Oral and Maxillary Area were repaired with tvascular forearm dermal fat flap. There were 8 males and 5 females, aged from 42-71 years. The flaps ranged from 8 cm×7 cm to 7 cm×5 cm in size. The donor site defects were covered by local split-thickness skin graft from the in situ skins. The color matching degree, surgical scars, ranges of wrist movement and hand sensations in donor forearms were assessed at 6 months after surgery. Results:The tvascular forearm dermal fat flaps for 15 cases all survived. All the local split-thickness skin grafts transplanted with this technique showed primary healing. The follow-up period for 6 months, Donor site exhibited suitabler color matching and there was not severe complications. Conclusion:The vascularized dermal fat flap provides an alternative to conventional forearm flap harvest, which enables primary donor site closure with reduced rates of delayed donor site healing. The vascularized dermal fat flap is a relatively reliable repair method for soft defects in Oral and Maxillary Area.

Clinical application of perforator-based propeller flaps in repair of hand wound

To investigate the effectiveness of the perforator-based propeller flaps (PPFs) based on digital artery (DA) and dorsal metacarpal artery (DMA) in repairing hand wounds. The clinical data of 45 patients with hand wounds between January 2018 and March 2023 were retrospectively analyzed. There were 27 males and 18 females with an average age of 41.2 years (range, 14-72 years). The causes of injury included twist injury in 15 cases, crush injury in 19 cases, and cut injury in 11 cases. The injured parts included 32 cases of digits, 10 cases of dorsal hand, and 3 cases of palmar hand, all of which had tendon, joint, and bone exposure. The time from injury to operation ranged from 2 to 8 hours (mean, 4.3 hours). The wound sizes after debridement ranged from 1.8 cm×1.0 cm to 5.0 cm×3.5 cm. Twenty-eight cases were repaired by the PPFs based on DA and 17 cases were repaired by the PPFs based on DMA. The flap size ranged from 2.5 cm×1.1 cm to 8.5 cm×4.0 cm. The defects of the donor sites in 14 patients were closed directly and the defects in the left 31 patients were resurfaced with free full-thickness skin graft from the proximal medial forearm. All the flaps survived after operation. Two cases of the PPF based on DA and 1 case of the PPF based on DMA underwent partially blisters at the distal end and healed after dressing change. The incisions in the donor site healed by first intention and the skin grafts survived. All patients were followed up 10-33 months, with a mean of 15.4 months. At last follow-up, the static two-point discrimination of the PPFs based on DA and DMA were 4-14 mm and 8-20 mm with the averages of 8.1 mm and 13.3 mm, respectively. According to the Michigan Hand Outcomes Questionnaire, 20 patients were very satisfied with the appearance of the PPF based on DA and 8 patients were satisfied; 8 patients were very satisfied with the appearance of the PPF based on DMA and 9 patients were satisfied. Based on the Vancouver Scar Scale (VSS), the appearance scores of the donor site of the PPFs based on DA and DMA were 2-7 and 4-9, with the averages of 4.2 and 6.1, respectively. The two kinds of PPFs are reliable in blood supply and easy to harvest, which provide a good method for emergency repair of small and medium area wounds in the hand.

A Simple and Effective Approach to Defatting Large Surface Area Full-thickness Skin Grafts.

Skin grafting is a fundamental tool in plastic surgery for the resurfacing of wounds resulting from burns, necrotizing infections, trauma, oncologic resections, donor site defects, and other causes. Compared with split-thickness skin grafts, full-thickness skin grafts (FTSGs) undergo less secondary contracture and often result in better aesthetic outcomes. To assure graft take, FTSGs require thorough defatting and adequate contact between the graft and the underlying wound bed. Conventionally, during the defatting process, FTSGs are stabilized on the surgeon's fingers, whereas curved scissors are used to remove the subcutaneous tissue. This approach is effective for small grafts, but for large FTSGs, it is time-consuming and ergonomically challenging.

Utility of large V-Y advancement of the latissimus dorsi myocutaneous flap in the reconstruction of large thoracic defects: a case series and literature review

BackgroundTrunk reconstruction following sarcoma excision involves significant defects. Pedicled and free latissimus dorsi myocutaneous flap (LDMF) reconstruction is commonly employed for thoracic defects; however, skin paddle design is limited to 10-12 cm to achieve primary donor closure. Paucity of data exists regarding the utility of V-Y advancement of LDMF, previously described for moderately sized thoracic defects. Efficacy of the technique's application, axial reach, maximum skin paddle, and overall success or complications have not been defined in the literature. MethodsA retrospective review of records was conducted from 2015 to 2021 at our center to identify patients who underwent large, islanded V-Y LDMF reconstructions. Results were assessed by reviewing photographs and clinical notes. PubMed search of articles using the search terms “Latissimus Dorsi Flap Reconstruction” AND “V-Y” was conducted, abstracts were screened, and relevant articles were selected for review by the 2 author (NL/YS). We summarized the findings in our review and discussion. ResultsEleven patients underwent V-Y LDMF reconstruction with large skin paddles designed to close the donor site and oncological defect. Flaps were mobilized in superior (n = 7), anterior (n = 2), inferior (n = 1) and medial (n = 1) directions. Satisfactory coverage and patient recovery with few complications was achieved. Average length of hospital stay was 4.7 days and secondary surgery was not required. Discussion and conclusionV-Y advancement of LDMF is reliable up to 24 cm axially with a skin paddle width of 24 cm based superiorly, inferiorly, or anteriorly. The technique is safe and effective in comorbid patients following high-dose radiotherapy, without prolonged general anesthesia or microsurgery. It represents a versatile locoregional reconstructive option for large trunk defects.

Immediate Latissimus Dorsi Flap Reconstruction: Assessing Aesthetic Outcomes Following Mastectomy in Breast Cancer Patients.

Breast Cancer has now become the leading cause of cancer-related deaths among women. In a traditional radical mastectomy, there can be complications that may affect the physiological characteristics of the breast and subsequently cause profound psychological stress to the patients. Hence, latissimus dorsi (LD) flap reconstruction provides an aesthetic approach in patients undergoing mastectomy. The goal is to maximize the flap's soft tissue coverage while minimizing the magnitude of donor site defect and complication. A prospective observational study was conducted in the Department of General Surgery, Safdarjung Hospital, New Delhi, India, where 30 breast cancer patients were enrolled and had undergone mastectomy with immediate LD flap reconstruction. Cosmetic assessments using BREAST-Q questionnaires were conducted postoperatively at various intervals starting from postoperative day one, week two, and week six. The subjective evaluation was done by the patient, while a blinded nurse and surgeon did the objective assessment. The majority (n=23, 76.7%) were aged 31-50 years. Initial postoperative BREAST-Q scores declined but significantly improved by week six, attributed to gradual wound healing over time, resulting in improved breast shape and contour. The objective scoring done by the blinded surgeon and nurse improved at six weeks compared to two weeks postoperatively. Almost similar outcomes were observed between preoperative and six-week postoperative scores with a significant overall p-value of <0.001. No significant statistical differences were noted between blinded surgeons and nurses for objective scoring. The rising trend of breast cancer in younger demographics emphasizes the importance of balancing cosmetic satisfaction with oncological outcomes. Immediate LD flap breast reconstruction provides a reliable means for soft tissue coverage with acceptable perioperative morbidities for patients undergoing mastectomy. Complication rates were acceptable, with donor site seroma, surgical site infection (SSI), and shoulder weakness among them. They could be prevented or treated (prolonged drain in situ, quilting sutures, and seroma aspiration) or resolved with time (SSI and shoulder function).

Human Acellular Collagen Matrices-Clinical Opportunities in Tissue Replacement.

The field of regenerative medicine is increasingly in need of effective and biocompatible materials for tissue engineering. Human acellular dermal matrix (hADM)-derived collagen matrices stand out as a particularly promising candidate. Their ability to preserve structural integrity, coupled with exceptional biocompatibility, positions them as a viable choice for tissue replacement. However, their clinical application has been largely confined to serving as scaffolds. This study aims to expand the horizon of clinical uses for collagen sheets by exploring the diverse cutting-edge clinical demands. This review illustrates the clinical utilizations of collagen sheets beyond traditional roles, such as covering skin defects or acting solely as scaffolds. In particular, the potential of Epiflex®, a commercially available and immediately clinically usable allogeneic membrane, will be evaluated. Collagen sheets have demonstrated efficacy in bone reconstruction, where they can substitute the induced Masquelet membrane in a single-stage procedure, proving to be clinically effective and safe. The application of these membranes allow the reconstruction of substantial tissue defects, without requiring extensive plastic reconstructive surgery. Additionally, they are found to be apt for addressing osteochondritis dissecans lesions and for ligament reconstruction in the carpus. The compelling clinical examples showcased in this study affirm that the applications of human ADM extend significantly beyond its initial use for skin defect treatments. hADM has proven to be highly successful and well-tolerated in managing various etiologies of bone and soft tissue defects, enhancing patient care outcomes. In particular, the application from the shelf reduces the need for additional surgery or donor site defects.

A comparative prospective study between the outcomes of one-stage Pelnac reconstruction and full thickness skin graft on donor site healing in the radial forearm and fibula flaps

ObjectivesDermal substitutes are classically used in a 2-stage procedure followed by skin graft for wound healing. This study aims to evaluate the possibility to use an alternative technique for radial forearm and fibula donor sites coverage using one-stage Pelnac reconstruction. Materials and methods21 patients who underwent radial forearm and fibula flaps harvest for reconstruction of head and neck defects after oncological surgery were enroled in the study. 13 patients were treated by one-stage Pelnac reconstruction of the donor site defect, 8 patients underwent full thickness skin graft. The Vancouver Scar Scale was used to evaluate the scar quality. ResultsMost patients treated with one-stage Pelnac reconstruction showed good healing of the flap donor site, with minor complications, scar quality comparable to other treatment options and unimpaired function of the implicated limb. One patient had wound dehiscence at the radial forearm site, which was treated with secondary full thickness skin graft. In the group treated with FTSG we had three patients that developed complications, such as dehiscence of the graft and seroma. Overall, we reported comparable satisfaction with donor sites both for aesthetic and functional outcomes, in both groups of patients. ConclusionThe use of Pelnac without a following skin graft provides a viable method for the reconstruction of radial forearm and fibula flaps donor site. A longer postoperative care is needed, but the long-term aesthetic and functional results are satisfactory in comparison with full thickness skin graft.

RETRACTION: Biphasic β-TCP mixed with silicon increases bone formation in critical site defects in rabbit calvaria.

J. L. Calvo-Guirado, M. Garces, R. A. Delgado-Ruiz, M. P. Ramirez Fernandez, E. Ferres-Amat, G. E. Romanos, "Biphasic β-TCP mixed with silicon increases bone formation in critical site defects in rabbit calvaria", Clinical Oral Implants Research 26, no. 8 (2015): 891-897, https://doi.org/10.1111/clr.12413 The above article, published online on 26 May 2014 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the journal's Editor in Chief, Lisa J. A. Heitz-Mayfield; and John Wiley & Sons Ltd. The retraction has been agreed due to concerns raised by third parties on the data presented in the article. Several flaws and inconsistencies between results presented and experimental methods described were found. Specifically, Figure2b has been used in a different context in another publication authored by the same group. Additionally, Figure3 and Figure5e appear to derive from the same histological sections depicted in another publication authored by the same group where it is used in a different context. Accordingly, the editors consider the findings of this article unreliable and the conclusions to be invalid. The authors have been informed of the decision to retract the article. The corresponding author J. L. Calvo-Guirado and co-authors M. Garces and R. A. Delgado-Ruiz disagree with the decision of retraction. The remaining co-authors were not available for a final confirmation of the retraction.

Medial sural artery perforator free flap versus radial forearm free flap in oral cavity reconstruction and donor site morbidity.

Radial Forearm Free flap (RFFF) is widely used in head and neck reconstruction, yet its donor site defect remains a significant drawback. The Medial Sural Artery Perforator Free Flap (MSAPFF) is considered an alternative flap to RFFF. This study aims to comprehensively analyze their characteristics, outcomes, and their impact on patient quality of life. All patients who underwent oral cavity reconstruction using RFFF and MSAPFF between February 2017 and April 2023 were included in this study. Flap characteristics, outcomes and post-operative complications were recorded and compared. Subjective donor site morbidity, aesthetic and functional results, and quality of life were also analyzed. The study included 76 patients: 37 underwent reconstruction with RFFF, and 39 with MSAPFF. There was no significance difference between the RFFF and MSAPFF regarding the success rate (97.2% vs 97.4%), flap size (4.8 × 8.8 cm2 vs 5 × 9.8 cm2), hospital of stay (15.5 days vs 13.5 days) and recipient site complications (P > 0.05). However, MSAPFF showed larger flap thickness (P = 0.001), smaller arterial caliber (P = 0.008), shorter pedicle length (P = 0.001), and longer harvesting time (P < 0.001). No significant difference was observed between the pre-and postoperative ranges of wrist and ankle movements or in recipient site complications. MSAPFF showed a significant difference in donor site morbidity (P < 0.05). The MSAPFF is an excellent alternative to the RFFF for repairing oral cavity defects, with additional advantage of a well-hidden scar on the posterior calf, a larger flap thickness, accepted pedicle length and arterial caliber. However, one should consider the harvesting time and surgical skills required in comparison to the RFFF. The study highlights the importance of the MSAPFF as an alternative option for RFFF with less donor site morbidity and high success rate in oral cavity reconstruction and improved patient Quality of life after ablative surgery.

Chemical Composition Modulation Realizing Remarkable Improvement of Thermoelectric Performance in CuInTe2-Based Alloy.

CuInTe2 (CIT) is one of the typical ternary chalcogenides known for its characteristic mixed polyanionic/polycationic site defects, making it a subject of continuous interest in the field of thermoelectrics. In this work, we propose a chemical composition modulation strategy for CIT by alloying GeTe and then introducing a copper deficiency (denoted by VCu). This strategy aims to unpin its Fermi level (Fr) and shift Fr into the valence band (VB) while simultaneously enabling coupling between the optical and acoustic phonon, thereby providing an extra phonon scattering path at low frequencies. The simultaneous composition regulations not only enhance the carrier concentration (nH) to 1019-1020 cm-3 but also significantly reduce the lattice thermal conductivity (κL) to ∼0.48 W m-1 K-1, thus effectively realizing electro-acoustic coordination in the present material. As a consequence, the thermoelectric (TE) performance is remarkably improved with the highest TE figure of merit (ZT) of 1.51 at ∼838 K. This value ranks at a higher level among CIT-based materials, which showcases the great significance of chemical composition modulation.

Partial loss of desmin expression due to a leaky splice site variant in the human DES gene is associated with neuromuscular transmission defects

Recessive desminopathies are rare and often present as severe early-onset myopathy. Here we report a milder phenotype in three unrelated patients from southern India (2 M, 1F) aged 16, 21, and 22 years, who presented with childhood-onset, gradually progressive, fatigable limb-girdle weakness, ptosis, speech and swallowing difficulties, without cardiac involvement. Serum creatine kinase was elevated, and repetitive nerve stimulation showed decrement in all. Clinical improvement was noted with pyridostigmine and salbutamol in two patients. All three patients had a homozygous substitution in intron 5: DES(NM_001927.4):c.1023+5G>A, predicted to cause a donor splice site defect. Muscle biopsy with ultrastructural analysis suggested myopathy with myofibrillar disarray, and immunohistochemistry showed partial loss of desmin with some residual staining, while western blot analysis showed reduced desmin. RT-PCR of patient muscle RNA revealed two transcripts: a reduced normal desmin transcript and a larger abnormal transcript suggesting leaky splicing at the intron 5 donor site. Sequencing of the PCR products confirmed the inclusion of intron 5 in the longer transcript, predicted to cause a premature stop codon. Thus, we provide evidence for a leaky splice site causing partial loss of desmin associated with a unique phenotypic presentation of a milder form of desmin-related recessive myopathy overlapping with congenital myasthenic syndrome.

Salvage of the cochlear implant in cases of skin breakdown over the receiver/stimulator in children

Objective and method: Skin breakdown over receiver/stimulator (RS) after cochlear implantation poses a serious challenge. We report our experience using a one-stage reconstruction and implant salvage approach. Results: Between the years 2005 and 2017 five children, all females, with congenital- bilateral sensorineural hearing loss were identified. In all cases, a temporoparietal fascia flap (TPFF) and a large scalp flap were used to provide a two-layer coverage to the exposed RS. In the first three cases, a split-thickness skin graft was used to cover the donor site defect. In the latter two cases, a larger rotation flap was used, and a skin graft was not required. One case required revision due to the dehiscence of the wound and exposure of the RS. In another case, an accidental electrode array explantation occurred and the patient underwent a revision cochlear implantation. All patients had achieved complete healing and no change in hearing thresholds with the implants. Conclusions: We demonstrate our one-stage salvage technique with TPFF that saves the implant and prevents a two-stage procedure. The success rate can be improved with special care at reconstruction and with better protection of the implant during the procedure.

Latissimus Dorsi Flap Revisited: Coverage of Large Chest Wall Defects Following Mastectomy for Locally Advanced Breast Carcinoma and Angiosarcoma.

The latissimus dorsi myocutaneous flap (LDMF) remains a significant tool in the armamentarium of the oncoplastic breast surgeon. Despite declining popularity for reconstruction, owing to the increasing use of implants and free flaps, it still has an important role in certain salvage situations and as a flap to cover large defects. We report our experience with the use of LDMF for immediate coverage of large mastectomy defects when options are limited. Retrospective series of prospectively collected patient records. Patient and tumour characteristics, length of stay, and post-operative and oncologic outcomes are reported. Patients with angiosarcoma were discussed at tertiary sarcoma centres as per national guidelines. Operations were carried out by oncoplastic breast surgeons. The case series was approved by the institutional information governance department in line with institutional requirements for patient data sharing. All patients provided written consent for photography. Descriptive statistics were used to report findings.Median (IQR) was used for continuous variables. Six women were included, with a median age of 62.5 years, from December 2019 to October 2022. Follow-up ranged from 15 to 49 months. Median tumour size was 72.5 (16.25) mm. Four patients had locally advanced breast carcinoma (LABC), and two had breast angiosarcoma. The donor site and chest wall defects were closed primarily in all cases. Median length of stay was three nights. All mastectomy wounds healed without issues and any delay to their adjuvant treatment. One patient had a minor latissimus dorsi (LD) donor site wound breakdown managed conservatively. Three patients had adjuvant radiotherapy after surgery. Four patients, one after high-grade angiosarcoma and three after aggressive breast carcinoma, had a locoregional recurrence or distant metastases and succumbed within 20 months of surgery. The LDMF can be a reliable option for the primary closure of large post-mastectomy wounds. Its use can lead to timely wound healing, allowing patients to undergo adjuvant treatment without delay. However, the overall oncologic outcomes in patients with LABC and angiosarcoma are poor due to the underlying aggressive tumour biology. Long-term outcomes are to be interpreted with caution due to the small number of patients with diverse pathologic features.

Defected twisted ring topology for autonomous periodic flip-spin-orbit soft robot.

Periodic spin-orbit motion is ubiquitous in nature, observed from electrons orbiting nuclei to spinning planets orbiting the Sun. Achieving autonomous periodic orbiting motions, along circular and noncircular paths, in soft mobile robotics is crucial for adaptive and intelligent exploration of unknown environments-a grand challenge yet to be accomplished. Here, we report leveraging a closed-loop twisted ring topology with a defect for an autonomous soft robot capable of achieving periodic spin-orbiting motions with programmed circular and re-programmed irregular-shaped trajectories. Constructed by bonding a twisted liquid crystal elastomer ribbon into a closed-loop ring topology, the robot exhibits three coupled periodic self-motions in response to constant temperature or constant light sources: inside-out flipping, self-spinning around the ring center, and self-orbiting around a point outside the ring. The coupled spinning and orbiting motions share the same direction and period. The spinning or orbiting direction depends on the twisting chirality, while the orbital radius and period are determined by the twisted ring geometry and thermal actuation. The flip-spin and orbiting motions arise from the twisted ring topology and a bonding site defect that breaks the force symmetry, respectively. By utilizing the twisting-encoded autonomous flip-spin-orbit motions, we showcase the robot's potential for intelligently mapping the geometric boundaries of unknown confined spaces, including convex shapes like circles, squares, triangles, and pentagons and concaves shapes with multi-robots, as well as health monitoring of unknown confined spaces with boundary damages.

A combined AIMD and DFT study of the low-energy radiation responses of GaN.

Although GaN is a promising candidate for semiconductor devices, degradation of GaN-based device performance may occur when the device is bombarded by high-energy charged particles during its application in aerospace, astronomy, and nuclear-related areas. It is thus of great significance to explore the influence of irradiation on the microstructure and electronic properties of GaN and to reveal the internal relationship between the damage mechanisms and physical characteristics. Using a combined density functional theory (DFT) and ab initio molecular dynamics (AIMD) study, we explored the low-energy recoil events in GaN and the effects of point defects on GaN. The threshold displacement energies (Eds) significantly depend on the recoil directions and the primary knock-on atoms. Moreover, the Ed values for nitrogen atoms are smaller than those for gallium atoms, indicating that the displacement of nitrogen dominates under electron irradiation and the created defects are mainly nitrogen vacancies and interstitials. The formation energy of nitrogen vacancies and interstitials is smaller than that for gallium vacancies and interstitials, which is consistent with the AIMD results. Although the created defects improve the elastic compliance of GaN, these radiation damage states deteriorate its ability to resist external compression. Meanwhile, these point defects lead the Debye temperature to decrease and thus increase the thermal expansion coefficients of GaN. As for the electronic properties of defective GaN, the point defects have various effects, i.e., VN (N vacancy), Gaint (Ga interstitial), Nint (N interstitial), and GaN (Ga occupying the N lattice site) defects induce the metallicity, and NGa (N occupying the Ga lattice site) defects decrease the band gap. The presented results provide underlying mechanisms for defect generation in GaN, and advance the fundamental understanding of the radiation resistances of semiconductor materials.

Double right triangular shape full-thickness skin grafts technique for short rectangular or square shape donor site defect - original method with a case report.

Full-thickness skin grafts are essential tools for reconstructive surgery. Rectangular or square secondary defect usually occurs after performing a cross-finger flap or homodigital island flap. With the traditional fusiform ellipse design, trimming out excess graft tissue is necessary. Double right triangular shape full-thickness skin grafts are designed to correct the problem.

Isovalent co-alloying contributes to considerable improvement in thermoelectric performance of BiSe bulks with weak anisotropy

BiSe with intrinsic low thermal conductivity has considered as a promising thermoelectric (TE) material at nearly room temperature. To improve its low thermoelectric figure of merit (zT), in this work, Sb and Te isovalent co-alloying was performed and significantly optimized its TE property with weakly anisotropic characteristic. After substituting Sb on Bi sites, the carrier concentration is suppressed by introduction of Sb Se site defects, which contributes to the increased absolute value of Seebeck coefficient (|S|). Further co-alloying Te on Se of the optimized composition Bi0.7Sb0.3Se, the carrier concentration increased without affecting the |S| due to the enhanced effective mass, which leads to a highest power factor of 12.8 μW/(cm·K2) at 423 K. As a result, a maximum zT of ∼0.54 is achieved for Bi0.7Sb0.3Se0.7Te0.3 along the pressing direction and the average zT (zTave) (from 300 K to 623 K) are drastically improved from 0.24 for pristine BiSe sample to 0.45. Moreover, an energy conversion efficiency ∼4.0% is achieved for a single leg TE device of Bi0.7Sb0.3Se0.7Te0.3when applied the temperature difference of 339 K, indicating the potential TE application.

Risk factor analysis for adverse prognosis of the fetal ventricular septal defect (VSD)

BackgroundVentricular septal defect (VSD) is the most common subtype of congenital heart disease. In the present study, we aimed to determine whether chromosome aberration was associated with the occurrence of VSD and evaluate the association of VSD size, location and chromosome aberration with adverse outcomes in the Chinese fetuses.MethodsFetuses with VSD and comprehensive follow-up data were included and evaluated retrospectively. Medical records were used to collect epidemiological data and foetal outcomes. For VSD fetuses, conventional karyotype and microarray analysis were conducted. After adjusting confounding factors by using multivariable logistic regression analyses, the association between chromosome variations and VSD occurrence was explored. The association between defect size, location and chromosome aberrations and adverse foetal outcomes was also investigated.ResultsChromosome aberration was the risk factor for VSD occurrence, raising 6.5-fold chance of developing VSD. Chromosome aberration, peri-membranous site and large defect size of VSD were significant risk factors of adverse fetal outcome. Chromosome aberrations, including pathogenic copy number variations (CNVs) and variations of uncertain significance (VUS), were both risk factors, increasing the risk of the adverse fetal outcome by 55.9 times and 6.7 times, respectively. The peri-membranous site would increase 5.3-fold risk and defects larger than 5 mm would increase the 7.1-fold risk for poor fetal outcome.ConclusionsThe current investigation revealed that chromosomal abnormalities, large defects, and the peri-membranous site were all risk factors for poor fetal outcomes. Our study also indicated that chromosome aberration was one of risk factors for the VSD occurrence.

Radially Pedicled In-Situ Split-Thickness Skin Grafts, an Alternative to Distal Split-Thickness Skin Grafts.

This study aimed to introduce a novel radially pedicled in-situ split-thickness skin graft (STSG). The morbidity, esthetic, and functional outcomes of the radially pedicled in-situ STSG were in comparison with those of the distal STSG. Retrospective analysis. A single-institution review. Seventy patients with oral cancer who underwent radical surgical resection and simultaneous radial forearm free flap (RFFF) reconstruction from July 2021 to March 2022 were included. De-epithelialized RFFFs and traditional RFFFs were used to repair oral defects of 35 patients in Group A and Group B, respectively, while radially pedicled in-situ STSGs and distal STSGs taken from abdomens were used to repair donor site defects in the above groups, respectively. Patient demographics, wound healing complications, and esthetic and functional outcomes of the forearms were compared between the 2 groups. No significant difference between Group A and Group B was observed in terms of donor site and recipient site complications. The esthetic outcome was superior in Group A compared to Group B (P = .011). The extension range, sensation, and pinch strength of operated forearms were significantly reduced in both groups after surgery (P < .05), however, intergroup differences were not observed. Taken together, our results suggest that radially pedicled in-situ STSG is an applicable technique for direct closure and better esthetic outcomes in the forearm donor site.