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Hydrogen storage holds a crucial place for the future of the world in terms of green energy. Two-dimensional materials, in particular, are important in this regard. The aim of this study is to evaluate the performance of MoS 2 which is one of the most popular member of two-dimensional materials family. To do this, bulk and exfoliated MoS 2 were used. Firstly, the liquid phase exfoliation method was employed to obtain exfoliated MoS 2 layers. Then, the hydrogen storage potential of the bulk and exfoliated MoS 2 was addressed under 1, 3, 5, 7, and 9 bar hydrogen pressure. After the absorption process, all the samples were characterized using XRD, Raman Spectrometer, and BET ahead of evaluating their hydrogen storage potential. The XRD pattern showed that the peak positions of bulk and exfoliated MoS 2 were not affected critically by hydrogen storage. In the Raman spectra, the A 1g and E 2g 1 peaks of all hydrogenated materials shifted to low wavelengths. Moreover, the BET measurements revealed that the specific surface area and the pore size of the bulk MoS 2 were 12.31 m2/g and ≤67.46 nm respectively. Additionally, the specific surface area and the pore size of the exfoliated MoS 2 were 23.16 m2/g and ≤69.28 nm, respectively. The hydrogen storage potential of the bulk and the exfoliated MoS 2 was evaluated through an MFC in sccm unit. The bulk and exfoliated MoS 2 stored 220 and 450 sccm hydrogen, respectively. Besides, the weight percent hydrogen storage for H–MoS 2 and H-exfoliated MoS 2 was determined to be 1.2 and 2.4 wt%, respectively. In summary, this study has shown that exfoliated MoS 2, one of the two-dimensional materials, can play a critical role for hydrogen storage due to their high specific surface area. • Exploring MoS 2 for hydrogen storage, both in bulk and exfoliated forms, reveals promising 2D material capabilities. • Exfoliated MoS 2 layers were successfully produced by liquid phase exfoliation method. • AFM confirms formation of few-layer nanosheets with thicknesses ranging from 2 to 6 nm (2–5 layers). • Exfoliated MoS 2 , stores up to 450 sccm and 2.4 % wt of hydrogen, surpassing the hydrogen capacity of MoS 2 at 7 bar. [ABSTRACT FROM AUTHOR]

Background: Spinopelvic dissociation (SPD) is difficult to manage and is associated with high mortality and morbidity, including concomitant orthopaedic polytrauma, spine injuries, pelvic ring disruptions, neurological, soft-tissue, and vascular injuries. The purpose of this study is to evaluate the functional and radiological outcomes; health related quality of life and complication rates of patients with traumatic spinopelvic dissociation underwent bilateral triangular osteosynthesis (TOS).Methods: The study was approved by the medical school's institutional review board (IRB). Prospective data collection of nineteen consecutive cases of traumatic SPD were included in the study from October 2015 to August 2018. Bilateral TOS was performed to manage all patients with SPD. The clinical outcome for fractures was analyzed with Majeed function assessment. Health Related Quality of Life (HRQoL) was assessed with the EQ-6D questionnaire. The reduction quality was evaluated according to Matta criterion. CT scanning was used to verify the fracture union in patients at 24th weeks postoperatively.Results: There were 12 women and 7 men with an average age of 47.2±8.4 years (range, 17-62 years). The average follow-up time was 25.2±3.7 months (average, 22-45 months). The most common mechanism of injury was falling (57%). According to Majeed functional scoring, the results were excellent in 12 cases, good in 5 cases and fair in 2 cases. The median EQVAS score was 78.9±8.4. 15 patients (78.9%) turned back to their original occupation. Pain and mood disorders mainly influenced patients' present general health status. According to Matta criterion for fracture reduction, the results were excellent in 14 cases, good in 4 cases and fair in 1 case. Complications were noted as wound healing problems (26%), implant loosening (5%) and iatrogenic nerve injury (5%).Conclusion: Bilateral TOS demonstrates satisfactory functional and radiological outcomes with low complication rates except infection rate in patients with traumatic spinopelvic dissociation. HRQoL is mainly dominated by pain and mood disorders. 78.9% of the patients turned back to their original occupation. Surgeons should be aware of wound healing problems in case of increased muscle mobilization and degloving injuries.Implant removal is required to improve the lumbopelvic mobility. [ABSTRACT FROM AUTHOR]

Abstract: Background context: Multilevel lumbar disc disease (MLDD) is a common finding in many patients. Surgical solutions for MLDD include fusion or disc replacement. The hybrid model, combining fusion and disc replacement, is a potential alternative for patients who require surgical intervention at both L5–S1 and L4–L5. The indications for this hybrid model could be posterior element insufficiency, severe facet pathology, calcified ligamentum flavum, and subarticular disease confirming spinal stenosis at L5–S1 level, or previous fusion surgery at L5–S1 and new symptomatic pathology at L4–L5. Biomechanical data of the hybrid model with the Maverick disc and anterior fusion are not available in the literature. Purpose: To compare the biomechanical properties of a two-level Maverick disc replacement at L4–L5, L5–S1, and a hybrid model consisting of an L4–L5 Maverick disc replacement with an L5–S1 anterior lumbar interbody fusion using multidirectional flexibility test. Study design: An in vitro human cadaveric biomechanical study. Methods: Six fresh human cadaveric lumbar specimens (L4–S1) were subjected to unconstrained load in axial torsion (AT), lateral bending (LB), flexion (F), extension (E), and flexion-extension (FE) using multidirectional flexibility test. Four surgical treatments—intact, one-level Maverick at L5–S1, two-level Maverick between L4 and S1, and the hybrid model (anterior fusion at L5–S1 and Maverick at L4–L5) were tested in sequential order. The range of motion of each treatment was calculated. Results: The Maverick disc replacement slightly reduced intact motion in AT and LB at both levels. The total FE motion was similar to the intact motion. However, the E motion is significantly increased (approximately 50% higher) and F motion is significantly decreased (30%–50% lower). The anterior fusion using a cage and anterior plate significantly reduced spinal motion compared with the condition (p<.05). No significant differences were found between two-level Maverick disc prosthesis and the hybrid model in terms of all motion types at L4–L5 level (p>.05). Conclusion: The Maverick disc preserved total motion but altered the motion pattern of the intact condition. This result is similar to unconstrained devices such as Charité. The motion at L4–L5 of the hybrid model is similar to that of two-level Maverick disc replacement. The fusion procedure using an anterior plate significantly reduced intact motion. Clinical studies are recommended to validate the efficacy of the hybrid model. [Copyright &y& Elsevier]

This study draws on our experiences with graphene to perform a hybrid TCO structure composed of AZO and graphene. We first set out to enhance the electrical and optical properties of AZO to enable its use especially in the field of solar cell. Hence, in our study, we deposited various thicknesses of AZO thin films on glass substrates and transferred single layer graphene on them to realize the formation of hybrid TCO structure. Among the various AZO film thicknesses, the optimum one, 300 nm, was determined and then the graphene film was added on top of the AZO film. This hybrid structure was applied to the silicon-based heterojunction solar cell with the idea of improving the cell performance. The cell performance fabricated using AZO film and AZO + graphene structure was analyzed using solar simulator. Our findings highlight the fact that the presence of graphene improved the cell efficiency by about 7%. Our research was further extended using ITO and ITO + graphene hybrid structure as TCO for silicon-based solar cell. We discovered that graphene incorporation increased the cell efficiency by almost 12% based on our results with ITO + graphene hybrid TCO structure on a similar cell. • Al doped-ZnO film thickness was optimized based on structural and physical properties. • A hybrid transparent conductive oxide structure was formed using graphene and AZO films. • The efficiency of the silicon-based solar cells with the hybrid structure increased by about 7%. • Graphene incorporated hybrid structures can be employed in many optoelectronic applications. [ABSTRACT FROM AUTHOR]

Introduction Burst fractures of the low lumbar spine constitute approximately one percent of all lumbar fractures. There is still no consensus on the optimal treatment of low lumbar burst factures. We aimed to evaluate the functional and radiographic outcomes of conservative treatment in patients with low lumbar burst fracture. Methods 15 patients (11 males, 4 females; mean age 32 ± 8) who had low lumbar spine burst fracture treated with a custom-moulded thoracolumbosacral orthosis (TLSO) with a thigh extension were enrolled. The mean follow-up period was 22 ± 6 months. 14 patients were neurologically intact and one had isolated nerve root injury. There were 24% type A fractures and 76% type B fractures according to the Denis classification system. Functional outcomes were evaluated by using Oswestry Disability Index (ODI), Short-Form 36 (SF-36) and Visual Analogue Scale (VAS). Radiographic outcome was analyzed by measuring anterior vertebral height loss, kyphosis angle, amount of canal retropulsion. Functional and radiographic outcomes were reviewed initially and at 1, 3, 6, 12 months, and at the latest follow-up. Functional and radiographic improvements were analyzed statistically. Results The mean bracing period was 11.9 ± 1.7 weeks. The mean initial ODI, SF-36, and VAS score of the patients was 78.3 ± 9.6, 23.7 ± 8.9, and 8.7 ± 0.7, respectively. The mean ODI, SF-36, and VAS score of the patients at the final follow-up was 26.4 ± 6.5, 68.1 ± 11.2, and 2.8 ± 1.7, respectively. The improvement in functional outcomes was measured to be significant ( p < 0.05 for ODI, SF-36 and VAS). The mean initial anterior vertebral height loss, kyphosis angle, amount of canal retropulsion was found to be 27.2% ± 9.6%, −6.8° ± 3.2°, 37.4% ± 10.2%, respectively. The mean anterior vertebral height loss, kyphosis angle, and amount of canal retropulsion at the final follow-up was 23.1% ± .6.7%, −4.2° ± 2.4°, 19.6% ± 7.7%, respectively. Among the radiographic outcomes, only the amount of canal retropulsion improved statistically ( p = 0.042). Conclusion Conservative treatment using a custom-moulded thoracolumbosacral orthosis with a thigh extension is a safe and effective method in patients with low lumbar spine burst fractures and can improve functional and radiographic outcomes. [ABSTRACT FROM AUTHOR]

Abstract: Background context: Euler and projection methods have been used to describe relative spinal motion. In the Eulerian formulation, the exiting method used vector form of Euler angles and only provides an approximation. In the projection method, local coordinate systems constructed with digitization can affect the accuracy of kinematical results. A more consistent data reduction method is desired to calculate relative spinal motion (range of motion) from raw marker data. Purpose: To develop a new data reduction method to calculate relative spinal motion based on arbitrarily oriented local coordinate systems of individual vertebrae, and to simplify experimental procedures in multidirectional testing of spines. Study design/setting: The relative spinal motion was determined from raw marker data using transformation matrices. Methods: In the Eulerian formulation, the relative motion of a vertebra to its subjacent level was determined using transformation matrices rather than vector operation on Euler angles. In the projection method, the projection axes were determined by tranforming local coordinate systems. Both approaches can be used to analyze raw marker data. Results: The new data reduction method was successfully implemented to analyze the raw data acquired on an intact L1–L2 motion segment. There was little difference between the Euler method and projection methods. Conclusions: In conclusion, an alternative data reduction method in both Euler and projection angles to calculate range of motion for in vitro spine biomechanical studies was presented. The method was validated on a human cadaveric lumbar motion segment under axial torsion, lateral bending, and flexion extension. Because the relative spinal motion does not depend on how local coordinate systems are oriented, the digitization process can be eliminated in most multidirectional flexibility tests. Compared with previous methods, this new method provides more consistent kinematical results and significantly simplifies experimental procedures. [Copyright &y& Elsevier]

Introduction Operative treatment consisting of fracture reduction and fixation, or arthroplasty to permit early patient mobilization, continues to be the treatment of choice for most femoral neck fractures. Options for internal fixation have included a variety of implants; however most recent reports and textbooks cite parallel multiple cancellous screws as the surgical technique of choice. Methods The study was prospective, randomized and IRB approved. Inclusion criteria included skeletal maturity, closed femoral neck fracture without concomitant fractures or injuries with complete charts and adequate radiographs obtained from the initial injury till the last follow-up. Forty-four patients were enrolled in this study during one-year period at two university centers. 22 were randomized to be treated with full threaded, cannulated compression screws (Acutrak 6/7, ACUMED) (Group 1) and the other 22 with 16 mm partial threaded, 6.5 mm or 7.3 mm cannulated screws (SYNTHES) (Group 2). Three or four screws were used in both groups according to fracture type and surgeon's preference. Data evaluated included surgical time, fluoroscopy time, fracture type, radiological outcome, complications and functional status using the Harris Hip Score. Results Both groups were comparable in terms of age and gender. There was not a significant difference in terms of surgical time, follow-up period, fracture type, or fluoroscopy time. There were eight complications in Group 1 and two in Group 2 ( P = 0.049) Time to union was significantly longer in Group 1 ( P = 0.001). However, Hip Scores were not significantly different in both groups ( P = 0.20). Conclusion When compared with full threaded compression screws, partial-threaded cannulated screws provides a shorter union time and less complication rate while providing equivalent functional results in adult femoral neck fractures. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To evaluate the biomechanics of lumbar motion segments instrumented with stand-alone OptiMesh system augmented with posterior fixation using facet or pedicle screws and the efficacy of discectomy and disc distraction. Background context: OptiMesh bone graft containment system has been used for vertebral compression fractures and percutaneous lumbar interbody fusion. The filled mesh bag serves as the interbody device providing structural support to the motion segment being fused. No biomechanical data of this new device are available in the literature. Methods: Twenty-four fresh human cadaveric lumbar motion segments were divided into two groups. In the control group, multidirectional flexibility testing was conducted after an intact condition and standard transforaminal lumbar interbody fusion (TLIF) procedure. In the OptiMesh group, testing was performed following intact, stand-alone OptiMesh procedure, OptiMesh with facet screws (placed using the transfacet approach), and OptiMesh with pedicle screws and rods. Range of motion (ROM) was calculated for each surgical treatment. The lordosis and disc height change of intact and instrumented specimens were measured in the lateral radiographs to evaluate the disc space distraction. In the OptiMesh group, cyclic loading in flexion extension (FE) was applied to measure cage subsidence or collapse (10,000 cycles at 6 Nm). After biomechanical testing, all the specimens were dissected to inspect the discectomy and end plate preparation. The area of discectomy was measured. Results: The mean ROM of the intact specimens was 2.7°, 7.4°, and 7.2° in axial torsion (AT), lateral bending (LB), and FE, respectively. There was no difference between the control group and OptiMesh group. The mean ROM of the stand-alone OptiMesh system decreased to 2.4°, 5.1°, and 4.3° in AT, LB, and FE. The ROM decreased to 0.9° in AT, 2.2° in LB, and 0.9° in FE with OptiMesh system and facet screws. On average, OptiMesh system with pedicle screws and rods reduced the ROM to 1.3° in AT, 1.6° in LB, and 1.1° in FE. Compared with the intact condition and stand-alone OptiMesh system, both posterior fixation options had significant statistical difference (p<.001). In AT, ROM of facet screws was lower than that of pedicle screws (p<.05). There was no statistical difference between the facet and pedicle screws in LB and FE (p>.05). The mean volume of bone graft packed into each bag was 8.3±1.5 cc. The average increase of lordosis was 0.6°±1.0° after meshed bag was deployed. The average distraction achieved by the OptiMesh system was 1.0±0.6 mm. The average prepared area of discectomy was 42% of the total disc. The disc height change after cyclic loading was 0.2 mm. No subsidence or collapse was noticed. Conclusions: The OptiMesh system offers large volume of bone graft in the disc space with small access portals. The OptiMesh system had similar construct stability to that of standard TLIF procedure when posterior fixation was applied. However, the amount of distraction was limited without additional distraction tools. With the anterior support provided by the expandable meshed bag, facet screws had comparable construct stability to that of pedicle screws. Slightly higher stability was observed in facet screws in AT. [Copyright &y& Elsevier]

Introduction The main aim of this retrospective study was to present our experience on scaphoid nonunion treated with vascularised bone graft. Methods Between 2006 and 2012, 58 patients presenting with symptomatic scaphoid nonunion were eligible to participate in this study. Topography of the nonunion included 29 proximal, 25 waist and 4 distal scaphoid nonunions. Vascularised bone graft from distal dorsal radius was used in all cases which were stabilised with the headless cannulated compression screws. Scapholunate angles, Natrass carpal height ratio were evaluated pre and postoperatively. Range of motion of the affected side was compared to that of the contralateral side after the surgery. Results Radiographic union was achieved in 50, out of 58 cases with an average time of 9.9 weeks (range, 6–18 weeks). Out of all the non-united cases, four of them were in proximal, three in the waist and one was in distal scaphoid. In nine proximal nonunions treated by 4 + 5 ECA graft all but one were united. The mean follow up was 21.7 months (12–62 months). The flexion was 91.6%, the extension was 91.5%, the radial deviation was 81.2%, and the ulnar deviation was 89.5% compared to the other side. The grip strength was 93%. Preoperative DASH score was 61.5 diminishing to 28.7 postoperatively. There was no significant change in Natrass carpal height ratio but a slight improvement occurred in scapholunate angles both pre and postoperatively. Conclusion Vascularised bone graft is a good solution for scaphoid nonunion to enhance the healing rate especially in the presence of avascular necrosis. Proximal pole nonunions, humpback deformity and smoking are important negative factors for scaphoid nonunion despite the use of a vascularised bone graft. A trapezoidal wedge graft is necessary for the volar type nonunions with humpback deformity. 1,2 ICSRA offer an advantage with its proximity to scaphoid in all nonunion locations. Nonetheless, 4 + 5 ECA graft is also a good solution for proximal nonunions. [ABSTRACT FROM AUTHOR]