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Subtotal calvarial vault reconstruction utilizing a customized polyetheretherketone (PEEK) implant with chimeric microvascular soft tissue coverage in a patient with syndrome of the trephined: A case report

  • Wang, Jessica S.;Louw, Ryan P. Ter;DeFazio, Michael V.;McGrail, Kevin M.;Evans, Karen K.
    • Archives of Plastic Surgery
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    • v.46 no.4
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    • pp.365-370
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    • 2019
  • The syndrome of the trephined is a neurologic phenomenon that manifests as sudden decline in cognition, behavior, and sensorimotor function due to loss of intracranial domain. This scenario typically occurs in the setting of large craniectomy defects, resulting from trauma, infection, and/or oncologic extirpation. Cranioplasty has been shown to reverse these symptoms by normalizing cerebral hemodynamics and metabolism. However, successful reconstruction may be difficult in patients with complex and/or hostile calvarial defects. We present the case of a 48-year-old male with a large cranial bone defect, who failed autologous cranioplasty secondary to infection, and developed rapid neurologic deterioration leading to a near-vegetative state. Following debridement and antibiotic therapy, delayed cranioplasty was accomplished using a polyetheretherketone (PEEK) implant with free chimeric latissimus dorsi/serratus anterior myocutaneous flap transfer for vascularized resurfacing. Significant improvements in cognition and motor skill were noted in the early postoperative period. At 6-month follow-up, the patient had regained the ability to speak, ambulate and self-feed-correlating with evidence of cerebral/ventricular re-expansion on computed tomography. Based on our findings, we advocate delayed alloplastic implantation with total vascularized soft tissue coverage as a viable alternative for reconstructing extensive, hostile calvarial defects in patients with the syndrome of the trephined.

Static and dynamic characterization of a flexible scaled joined-wing flight test demonstrator

  • Carregado, Jose;Warwick, Stephen;Richards, Jenner;Engelsen, Frode;Suleman, Afzal
    • Advances in aircraft and spacecraft science
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    • v.6 no.2
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    • pp.117-144
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    • 2019
  • High Altitude and Long Endurance (HALE) aircraft are capable of providing intelligence, surveillance and reconnaissance (ISR) capabilities over vast geographic areas when equipped with advanced sensor packages. As their use becomes more widespread, the demand for additional range, endurance and payload capability will increase and designers are exploring non-conventional configurations to meet the increasing demands. One such configuration is the joined-wing concept. A joined-wing aircraft is one that typically connects a front and aft wings in a diamond shaped planform. One such example is the Boeing SensorCraft configuration. While the joined-wing configuration offers potential benefits regarding aerodynamic efficiency, structural weight, and sensing capabilities, structural design requires careful consideration of elastic buckling resulting from the aft wing supporting, in compression, part of the forward wing structural loading. It has been shown already that this is a nonlinear phenomenon, involving geometric nonlinearities and follower forces that tend to flatten the entire configuration, leading to structural overload due to the loss of the aft wing's ability to support the forward wing load. Severe gusts are likely to be the critical design condition, with flight control system interaction in the form of Gust Load Alleviation (GLA) playing a key role in minimizing the structural loads. The University of Victoria Center for Aerospace Research (UVic-CfAR) has built a 3-meter span scaled and flexible wing UAV based on the Boeing SensorCraft design. The goal is to validate the nonlinear structural behavior in flight. The main objective of this research work is to perform Ground Vibration Tests (GVT) to characterize the dynamic properties of the scaled flight vehicle. Results from the experimental tests are used to characterize the modal dynamics of the aircraft, and to validate the numerical models. The GVT results are an important step towards a safe flight test program.

Clinical Efficacy of Intra-Operative Cell Salvage System in Major Spinal Deformity Surgery

  • Choi, Ho Yong;Hyun, Seung-Jae;Kim, Ki-Jeong;Jahng, Tae-Ahn;Kim, Hyun-Jib
    • Journal of Korean Neurosurgical Society
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    • v.62 no.1
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    • pp.53-60
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    • 2019
  • Objective : The purpose of this study was to determine the efficacy of intra-operative cell salvage system (ICS) to decrease the need for allogeneic transfusions in patients undergoing major spinal deformity surgeries. Methods : A total of 113 consecutive patients undergoing long level posterior spinal segmental instrumented fusion (${\geq}5$ levels) for spinal deformity correction were enrolled. Data including the osteotomy status, the number of fused segments, estimated blood loss, intra-operative transfusion amount by ICS (Cell $Saver^{(R)}$, $Haemonetics^{(C)}$, Baltimore, MA, USA) or allogeneic blood, postoperative transfusion amount, and operative time were collected and analyzed. Results : The number of patients was 81 in ICS group and 32 in non-ICS group. There were no significant differences in demographic data and comorbidities between the groups. Autotransfusion by ICS system was performed in 53 patients out of 81 in the ICS group (65.4%) and the amount of transfused blood by ICS was 226.7 mL in ICS group. The mean intra-operative allogeneic blood transfusion requirement was significantly lower in the ICS group than non-ICS group (2.0 vs. 2.9 units, p=0.033). The regression coefficient of ICS use was -1.036. Conclusion : ICS use could decrease the need for intra-operative allogeneic blood transfusion. Specifically, the use of ICS may reduce about one unit amount of allogeneic transfusion in major spinal deformity surgery.

Cone-beam computed tomography-guided three-dimensional evaluation of treatment effectiveness of the Frog appliance

  • Li, Mujia;Su, Xiaoxia;Li, Yang;Li, Xianglin;Si, Xinqin
    • The korean journal of orthodontics
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    • v.49 no.3
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    • pp.161-169
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    • 2019
  • Objective: To evaluate the effectiveness of the Frog appliance in three dimensions by using cone-beam computed tomography (CBCT) images. Methods: Forty patients (21 boys and 19 girls), averaged 11.7 years old, with an Angle Class II division 1 malocclusion were included in our study. They had either late mixed dentition or early permanent dentition, and the maxillary second molars had not yet erupted. All patients underwent CBCT before and after the treatment for measuring changes in the maxillary first molars, second premolars, central incisors, and profile. Paired-samples t-test was used to compare the mean difference in each variable before treatment and after the first phase of treatment. Results: The maxillary first molars were effectively distalized by 4.25 mm (p < 0.001) and 3.53 mm (p < 0.05) in the dental crown and root apex, respectively. The tipping increased by $2.25^{\circ}$, but the difference was not significant. Moreover the teeth moved buccally by 0.84 mm (p < 0.05) and 2.87 mm (p < 0.01) in the mesiobuccal and distobuccal cusps, respectively, whereas no significant changes occurred in the root apex. Regarding the anchorage parts, the angle of the maxillary central incisor's long axis to the sella-nasion plane increased by $2.76^{\circ}$ (p < 0.05) and the distance from the upper lip to the esthetic plane decreased by 0.52 mm (p = 0.01). Conclusions: The Frog appliance effectively distalized the maxillary molars with an acceptable degree of tipping, distobuccal rotation, and buccal crown torque, with only slight anchorage loss. Furthermore, CBCT image demonstrated that it is a simple and reliable method for three-dimensional analysis.

Study on the Removal of the Cable Braid Inside the Missile (유도탄 탄내케이블 브레이드 제거에 따른 고찰)

  • Eun, Hee-hyun;Kim, Ji-min;Lee, Min-hyoung;Jung, Jae-won
    • Journal of Advanced Navigation Technology
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    • v.22 no.2
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    • pp.105-110
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    • 2018
  • The North Korea nuclear issue is now posing a serious security threat to the Korea and Northeast Asia. Accordingly, the South Korean military is pushing for the introduction of long-range air-to-surface flights and the development of domestic nuclear facilities that can precisely hit North Korea headquarters building and nuclear facility even hundreds of kilometers above the border. In this paper, we removed the cable braid for securing the weight of the missile among several design elements for long-range air-to-surface missile development and estimated and analyzed the resulting performance. The possibility of braid removal was analyzed in terms of crosstalk inside the cable and CS114, RE101 of MIL-STD-461F.

Ginsenosides repair UVB-induced skin barrier damage in BALB/c hairless mice and HaCaT keratinocytes

  • Li, Zhenzhuo;Jiang, Rui;Wang, Manying;Zhai, Lu;Liu, Jianzeng;Xu, Xiaohao;Sun, Liwei;Zhao, Daqing
    • Journal of Ginseng Research
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    • v.46 no.1
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    • pp.115-125
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    • 2022
  • Background: Ginsenosides (GS) have potential value as cosmetic additives for prevention of skin photoaging. However, their protective mechanisms against skin barrier damage and their active monomeric constituents are unknown. Methods: GS monomer types and their relative proportions were identified. A UVB-irradiated BALB/c hairless mouse model was used to assess protective effects of GS components on skin epidermal thickness and transepidermal water loss (TEWL). Skin barrier function, reflected by filaggrin (FLG), involucrin (IVL), claudin-1 (Cldn-1), and aquaporin 3 (AQP3) levels and MAPK phosphorylation patterns, were analyzed in UVB-irradiated hairless mice or HaCaT cells. Results: Total GS monomeric content detected by UPLC was 85.45% and was largely attributed to 17 main monomers that included Re (16.73%), Rd (13.36%), and Rg1 (13.38%). In hairless mice, GS ameliorated UVB-induced epidermal barrier dysfunction manifesting as increased epidermal thickness, increased TEWL, and decreased stratum corneum water content without weight change. Furthermore, GS treatment of UVB-irradiated mice restored protein expression levels and epidermal tissue distributions of FLG, IVL, Cldn-1, and AQP3, with consistent mRNA and protein expression results obtained in UVB-irradiated HaCaT cells (except for unchanging Cldn-1 expression). Mechanistically, GS inhibited JNK, p38, and ERK phosphorylation in UVB-irradiated HaCaT cells, with a mixture of Rg2, Rg3, Rk3, F2, Rd, and Rb3 providing the same protective MAPK pathway inhibition-associated upregulation of IVL and AQP3 expression as provided by intact GS treatment. Conclusion: GS protection against UVB-irradiated skin barrier damage depends on activities of six ginsenoside monomeric constituents that inhibit the MAPK signaling pathway.

Application of sigmoidal optimization to reconstruct nuclear medicine image: Comparison with filtered back projection and iterative reconstruction method

  • Shin, Han-Back;Kim, Moo-Sub;Law, Martin;Djeng, Shih-Kien;Choi, Min-Geon;Choi, Byung Wook;Kang, Sungmin;Kim, Dong-Wook;Suh, Tae Suk;Yoon, Do-Kun
    • Nuclear Engineering and Technology
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    • v.53 no.1
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    • pp.258-265
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    • 2021
  • High levels for noise and a loss of true signal make the quantitative interpretation of nuclear medicine (NM) images difficult. An application of profile optimization using a sigmoidal function in this study was used to acquire the NM images with high quality. And the images were acquired by using three kinds of reconstruction method using each same sinogram: a standard filtered back-projection (FBP), an iterative reconstruction (IR) technique, and the sigmoidal function profile optimization (SFPO). Comparison of image according to reconstruction method was performed to show a superiority of the SFPO for imaging. The images reconstructed by using the SFPO showed an average of 1.49 times and of 1.17 times better in contrast than the results obtained using the standard FBP and the IR technique, respectively. Higher signal to noise ratios were obtained as an average of 12.30 times and of 3.77 times than results obtained using the standard FBP and the IR technique, respectively. This study confirms that reconstruction with SFPO (vs FBP and vs IR) can lead to better lesion detectability and characterization with noise reduction. It can be developed for future reconstruction technique for the NM imaging.

High-Speed Maritime Object Detection Scheme for the Protection of the Aid to Navigation

  • Lee, Hyochan;Song, Hyunhak;Cho, Sungyoon;Kwon, Kiwon;Park, Sunghyun;Im, Taeho
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.16 no.2
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    • pp.692-712
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    • 2022
  • Buoys used for Aid to Navigation systems are widely used to guide the sea paths and are powered by batteries, requiring continuous battery replacement. However, since human labor is required to replace the batteries, humans can be exposed to dangerous situation, including even collision with shipping vessels. In addition, Maritime sensors are installed on the route signs, so that these are often damaged by collisions with small and medium-sized ships, resulting in significant financial loss. In order to prevent these accidents, maritime object detection technology is essential to alert ships approaching buoys. Existing studies apply a number of filters to eliminate noise and to detect objects within the sea image. For this process, most studies directly access the pixels and process the images. However, this approach typically takes a long time to process because of its complexity and the requirements of significant amounts of computational power. In an emergent situation, it is important to alarm the vessel's rapid approach to buoys in real time to avoid collisions between vessels and route signs, therefore minimizing computation and speeding up processes are critical operations. Therefore, we propose Fast Connected Component Labeling (FCCL) which can reduce computation to minimize the processing time of filter applications, while maintaining the detection performance of existing methods. The results show that the detection performance of the FCCL is close to 30 FPS - approximately 2-5 times faster, when compared to the existing methods - while the average throughput is the same as existing methods.

Establishment of a BaTiO3-based Computational Science Platform to Predict Multi-component Properties (다성분계 물성을 예측하기 위한 BaTiO3기반 계산과학 플랫폼 구축)

  • Lee, Dong Geon;Lee, Han Uk;Im, Won Bin;Ko, Hyunseok;Cho, Sung Beom
    • Journal of Sensor Science and Technology
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    • v.31 no.5
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    • pp.318-323
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    • 2022
  • Barium titanate (BaTiO3) is considered to be a beneficial ceramic material for multilayer ceramic capacitor (MLCC) applications because of its high dielectric constant and low dielectric loss. Numerous attempts have been made to improve the physical properties of BaTiO3 in response to recent market trends by employing multicomponent alloying strategies. However, owing to its significant number of atomic combinations and unpredictable physical properties, finding a traditional experimental approach to develop multicomponent systems is difficult; the development of such systems is also time-consuming. In this study, 168 new structures were fabricated using special quasi-random structures (SQSs) of Ba1-xCaxTi1-yZryO3, and 1680 physical properties were extracted from first-principles calculations. In addition, we built an integrated database to manage the computational results, and will provide big data solutions by performing data analysis combined with AI modeling. We believe that our research will enable the global materials market to realize digital transformation through datalization and intelligence of the material development process.

Se Incorporation in VTD-SnS by RTA and Its Influence on Performance of Thin Film Solar Cells

  • Yadav, Rahul Kumar;Kim, Yong Tae;Pawar, Pravin S.;Heo, Jaeyeong
    • Current Photovoltaic Research
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    • v.10 no.2
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    • pp.33-38
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    • 2022
  • Planner configuration thin film solar cells (TFSCs) with SnS/CdS heterojunction performed a lower short-circuit current (JSC). In this study, we have demonstrated a path to overcome deficiency in JSC by the incorporation of Se in the SnS absorber. We carried out the incorporation of Se in VTD grown SnS absorber by rapid thermal annealing (RTA). The diffusion of Se is mostly governed by RTA temperature (TRTA), also it is observed that film structure changes from cube-like to plate-like structure with TRTA. The maximum JSC of 23.1 mA cm-2 was observed for 400℃ with an open-circuit voltage (VOC) of 0.140 V for the same temperature. The highest performance of 2.21% with JSC of 18.6 mA cm-2, VOC of 0.290 V, and fill factor (FF) of 40.9% is observed for a TRTA of 300℃. In the end, we compare the device performance of Se- incorporated SnS absorber with pristine SnS absorber material, increment in JSC is approximately 80% while a loss in VOC of about 20% has been observed.