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Objective: To present a case of transorbital penetrating intracranial injury successfully managed using a stepwise multispecialty approach. Methods: This is a case report. Results: A 26-year-old male presented with a motorcycle side-mirror metal bar impaled into his right orbit. He had a Glasgow Coma Scale (GCS) score of 12. Computed tomography (CT) imaging revealed the metal bar’s trajectory from the right lateral canthus, traversing the superior orbital wall and frontal lobe, resulting in contusion, intracranial hemorrhages and multiple orbital and facial fractures. Despite the severity of the injury, the right globe was found to be intact during intraoperative exploration. The transorbital approach was employed for safe removal of the penetrating object, followed by repair of full-thickness eyelid laceration and transections of the lateral and medial canthi. Subsequently, the Neurosurgery service conducted a right pterional craniotomy, debridement, and duraplasty. Upon discharge, the visual acuity on the right eye was 20/50. Conclusion: Transorbital penetrating intracranial injuries are rare and result in vision loss and life-threatening complications. A transorbital approach in removing a penetrating foreign body can be adopted when injury to cerebral tissues is imminent. Individualizing the management and employing a multispecialty approach can lead to favorable outcomes.

Objective: To present a case of transorbital penetrating intracranial injury successfully managed using a stepwise multispecialty approach. Methods: This is a case report. Results: A 26-year-old male presented with a motorcycle side-mirror metal bar impaled into his right orbit. He had a Glasgow Coma Scale (GCS) score of 12. Computed tomography (CT) imaging revealed the metal bar's trajectory from the right lateral canthus, traversing the superior orbital wall and frontal lobe, resulting in contusion, intracranial hemorrhages and multiple orbital and facial fractures. Despite the severity of the injury, the right globe was found to be intact during intraoperative exploration. The transorbital approach was employed for safe removal of the penetrating object, followed by repair of full-thickness eyelid laceration and transections of the lateral and medial canthi. Subsequently, the Neurosurgery service conducted a right pterional craniotomy, debridement, and duraplasty. Upon discharge, the visual acuity on the right eye was 20/50. Conclusion: Transorbital penetrating intracranial injuries are rare and result in vision loss and life-threatening complications. A transorbital approach in removing a penetrating foreign body can be adopted when injury to cerebral tissues is imminent. Individualizing the management and employing a multispecialty approach can lead to favorable outcomes. [ABSTRACT FROM AUTHOR]

In this article, a 2 × 2 stacked patch antenna array with low profile (0.047 λ0) and compact size (the center to center distance of two subarrays is 0.5 λ0) is presented. To reduce mutual coupling, a metal bar is disposed between the two subarrays. By investigating the current density distribution on the metal bar, the decoupling effect of the metal bar is explained. The proposed design is also fabricated and tested. The results show that operating bandwidth of 1.71 to 1.88 GHz is covered, with voltage standing wave ratio (VSWR) <1.4. The isolations between the co‐polarized ports and orthogonally‐polarized ports are higher than 27.5 and 27 dB, respectively. Stable radiation patterns are obtained over the operating frequency band. Due to the low mutual coupling between the adjacent elements, the half‐power beamwidth of the antenna array well converges. [ABSTRACT FROM AUTHOR]

Extensive studies have shown that engineering materials, including metals and their oxides, will present different mechanical properties in tension or compression; however, this difference is generally neglected due to the complexity of the analysis. In this study, we theoretically analyze the thermal stress of a metal bar with a bimodular effect. First, the common strain suppression method is used to obtain a one-dimensional thermal stress expression. As a contrast with the one-dimensional solution, a two-dimensional thermoelasticity solution is also derived, based on the classical Duhamel theorem concerning body force analogy. Results indicate an important phenomenon that the linear temperature rise mode will produce thermal stress in a bimodular metal bar, whereas there is no thermal stress in the case of singular modulus. If the equilibrium relation is needed to be satisfied, the variation trend between different moduli and different thermal expansion coefficients in tension and compression should be opposite. In addition, the amplitude of stress variation, from the maximum tensile stress to the maximum compressive stress, increases dramatically. There exists an inevitable link between one- and two-dimensional solutions. These results are helpful to the refined analysis and measurements of the thermophysical properties of metals and their oxides.

Introduction Penetrating brain injury (PBI) is uncommon among the civilian population. Here, we report two interesting cases of PBI. Case presentation The first patient was a 20-year-old male who sustained a penetrating head injury with a metal bar during an accident at work. The patient underwent early surgical intervention, and related meningitis was treated with antibiotics. The patient was discharged 45 days later with no deficit. The second patient was a 34-year-old male who was the victim of a violence attack and was admitted to hospital. He was struck by a knife to his right temporal bone. A brain computed tomography scan and magnetic resonance imaging (MRI) demonstrated the tract of the knife within the brain parenchyma. The patient underwent conservative treatment. After several weeks, the patient was discharged in good health. Conclusion Although severe PBI has a poorer prognosis than a blunt brain injury, in treating of these patients, aggressive and timely surgical intervention, proper wide-spectrum antibiotic administration, stringent and diligent care in the intensive-care unit and careful management of the associated complications are mandated. [ABSTRACT FROM AUTHOR]

In this article, a new controllable and near net low-stress bar fine-cropping system was proposed and developed by combined using the stress concentration effect of the prefabricated V-groove and the propagation crack. The bar finecropping experiments were successfully carried out using a new proposed cropping load control strategy. Although the level of the stress intensity factor range DK greatly influences the cropping time and the cross-section quality, the cropped-billets can be directly used for the precision forging industry without additional machining. [ABSTRACT FROM AUTHOR]

The horizontal bar, from its invention until the middle of the 19th century, underwent several phases of evolution; it remained however, wooden and fixed to the ground. The exercises were static, dynamic, close to the bar, and without amplitude and swing. In the middle of the 19th century, metal bars and then height-adjustable horizontal bars started to appear. From this new and more favourable apparatus more difficult exercises and combinations with swing and amplitude emerged, while the static and dynamic exercises continued. In the 80s, the stabilizers for the wooden pillars appeared, while in the last decade of the 19th century, the iron flexible horizontal bar was constructed with stabilizing chains and a height-adjusting mechanism. Such a horizontal bar was also used in the 1896 Olympics, where exercises with amplitude and swing but also static and dynamic exercises were performed. The aim of this work was to research and highlight the main features of the evolution of the horizontal bar (exercises, regulations and apparatus) in the second half of the 19th century. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate implant and prosthetic survival rates, complications, patient satisfaction, and biological outcomes of patients rehabilitated with a ball attachment system for implant retained- and supported-overdentures (IOV), which was in function for 3 to 5 years. Methods: This retrospective study evaluated data collected from patients treated between April 2001 and May 2018 with IOV on splinted and non-splinted implants and a ball attachment system. Patients were followed for 36 to 206 months (mean follow-up was 128.1 ± 51.9 months). Data were collected at the 3- and 5-year follow-up examination. Outcome measures were implant and prosthetic survival rates, technical complications, marginal bone loss (MBL), oral health impact profile (OHIP), and periodontal parameters (bleeding on probing and plaque index). Results: A total of 46 patients (16 males and 30 females) with 124 implants were included in this study. Twenty-five implant-retained overdentures were delivered on 53 unsplinted implants, while the other 21 patients received an implant-supported overdentures and the implants were splinted. At the five-year follow-up examination, one implant and one prosthesis failed in the unsplinted group, resulting in a cumulative survival rate of 97.8% at the patient level. Two minor technical complications were experienced. Conclusions: Implant overdenture retained or supported by ball attachment systems showed high implant and prosthetic survival and success rates. A low number of complications, high patient satisfaction, and successful biological parameters were experienced in the mid-term follow-up. Data need to be confirmed by further randomized trials.

Transorbital intracranial injury is uncommon, representing 0.04% of penetrating head trauma with a high mortality rate. Orbital penetrating injuries may cause severe brain injury if the cranium is entered, typically via the orbital roof, the superior orbital fissure, or the optic canal. A 13-year-old male sustained a severe brain injury due to penetration of the right orbit with an iron bar. The bar entered the inferiomedial aspect of the orbit and emerged from the left occipital bone. Neurological examination revealed deep coma (GCS: E1M2V1) with fixed, dilated, and non-reactive pupils. The bar followed an intracranial trajectory, through the third ventricle and suprasellar cistern. The patient underwent an immediate exploration with removal of the bar. Unfortunately, he died 10 days postoperatively due to severe diencephalic injury with brainstem herniation. In this case report, we discuss the radiologic diagnosis and surgical management of transorbital orbitocranial injury by foreign body penetration. [ABSTRACT FROM AUTHOR]

The straightening technics is one of important means to improve the straightness of metal bar. A novel way of predicting the straightening stroke is proposed based on mathematical methods and bending experimental and numerical simulation. The experimental and numerical simulation is conducted by following the mathematical load-stroke model of press straightening process under the elastic-plastic theory. For the linear guide rails, as an example, the stroke-deflection model focusing on the straightening stroke prediction can be achieved by contrasting and integrating the bending experimental results and finite element methods (FEM) simulation data. And then the formula for predicting the straightening stroke is presented based on the precise straightening stroke-deflection model. The stroke prediction formula with high precision can be applied to the straightening stroke prediction in the high straightness metal bar manufacturing process and automatic straightening machine conveniently. [ABSTRACT FROM AUTHOR]

Extensive studies have shown that engineering materials, including metals and their oxides, will present different mechanical properties in tension or compression; however, this difference is generally neglected due to the complexity of the analysis. In this study, we theoretically analyze the thermal stress of a metal bar with a bimodular effect. First, the common strain suppression method is used to obtain a one-dimensional thermal stress expression. As a contrast with the one-dimensional solution, a two-dimensional thermoelasticity solution is also derived, based on the classical Duhamel theorem concerning body force analogy. Results indicate an important phenomenon that the linear temperature rise mode will produce thermal stress in a bimodular metal bar, whereas there is no thermal stress in the case of singular modulus. If the equilibrium relation is needed to be satisfied, the variation trend between different moduli and different thermal expansion coefficients in tension and compression should be opposite. In addition, the amplitude of stress variation, from the maximum tensile stress to the maximum compressive stress, increases dramatically. There exists an inevitable link between one- and two-dimensional solutions. These results are helpful to the refined analysis and measurements of the thermophysical properties of metals and their oxides. [ABSTRACT FROM AUTHOR]

Trans-orbital orbitocranial penetrating injury (TOPI) by a foreign body is an extremely rare compound head injury having a potential to cause major morbidity and mortality. Preoperative radiological imaging by CT scan is very important for operative guidance, but in remote area where CT scan is not available, the patient is generally referred to tertiary level. Here we present a case which was dealt successfully without CT scan, only on the basis of stable clinical status and X-rays. We present a case of a 35-year-old man who had an accidental injury (fall from height) by rod. Immediate X-ray (anteroposterior and lateral views) revealed that the pointed end of the foreign body (rod) was inside the ipsilateral anterior fossa via basifrontal bone up to frontal vertex, not crossing the midline. CT scan was not available and his vitals with GCS were normal (15/15). He was operated with the help of an ophthalmic surgeon by right frontotemporal craniotomy. The patient was discharged on 10th day without any neurological deficit except restricted right eyeball movement to superolateral and ptosis. The restricted eyeball movements recovered after third month of follow up with remnant ptosis for 2 years. This case highlights an unusual case, direct visualization and repair of brain structures with higher antibiotics can save the life even in remote areas where CT scan is still not available only on the basis of stable GCS and X-rays. [ABSTRACT FROM AUTHOR]

A laser-assisted high-speed shearing (LAHSS) method has been proposed for metal bars, which prefabricates equally spaced fracture-start kerfs by Nd:Yag laser to make stress concentration, and applies a high-speed load to complete fracture separation. Comparative tests were conducted for Q235, 40Cr, and 304 steel bars, and the effects of fracture-start kerfs and axial clearance were investigated on the fracture section. Moreover, the fracture behavior was demonstrated by numerical simulation, and the micro-fracture mechanism was revealed by fractographic analysis. The numerical simulation results show that the material damage concentrates along with the kerf tips with peak equivalent plastic strain, and the corresponding stress triaxiality drops to almost zero at the kerf tip, which reveals that the material is subjected to pure shearing at kerf tip; the Max. loading force is reduced by 15.2%–29.6%, and the impact energy is decreased by 29.8%–46.9% for the three types of bar material. The experimental results showed that the fracture-start kerfs effectively inhibited the plastic deformation stage, and higher precision blanks were obtained in the LAHSS test: roundness error improved from 2.7%–10.9% to 1.1%–2.6%, Max. bending deflection decreased from 1.3–3.4 mm to 0.4–1.0 mm, and flatness error dropped from 0.9–3.3 mm to 0.3–0.7 mm. The fractographic analysis reveals that the crack initiation is related to alternative V-shape micro-notches at the laser-affected zone; the predominant fracture mechanism involves mode II microvoid coalescence at the main fracture plane; smaller and less elongated dimples were formed in 40Cr steels due to higher number density of grains and pinning effect of second-phase particles compared to Q235 and 304 steel bars. [ABSTRACT FROM AUTHOR]

A notch-induced high-speed splitting method was developed for high-quality cropping of metal bars using a new type of electric-pneumatic counter hammer. Theoretical equations and FE models were established to reveal the crack initiation and fracture mode. Comparative tests were conducted for notched and unnotched bars of four types of steels, i.e., AISI 1020, 1045, 52100, and 304, and the section quality and microfracture mechanism were further investigated. The results show that damage initiates at the bilateral notch tips with peak equivalent plastic strain, and propagates through the plane induced by the notch tip; the stress triaxiality varies as a quasi-sine curve, revealing that the material is subjected to pure shearing at the notch tip, and under compression at the adjacent region. High precision chamfered billets were obtained with roundness errors of 1.1–2.8%, bending deflections of 0.5–1.5mm, and angles of inclination of 0.7°–3.4°. Additionally, the notch effectively reduced the maximum impact force by 21.6–23.9%, splitting displacement by 7.6–18.6%, and impact energy by 27.8–39.1%. The crack initiation zone displayed quasi-parabolic shallow dimples due to shear stress, and the pinning effect was larger in AISI 52100 and 1045 steel; the final rupture zone was characterized by less elongated and quasi-equiaxial deeper dimples due to the combination of shear and normal stress. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate implant and prosthetic survival rates, complications, patient satisfaction, and biological outcomes of patients rehabilitated with a ball attachment system for implant retained- and supported-overdentures (IOV), which was in function for 3 to 5 years. Methods: This retrospective study evaluated data collected from patients treated between April 2001 and May 2018 with IOV on splinted and non-splinted implants and a ball attachment system. Patients were followed for 36 to 206 months (mean follow-up was 128.1 ± 51.9 months). Data were collected at the 3- and 5-year follow-up examination. Outcome measures were implant and prosthetic survival rates, technical complications, marginal bone loss (MBL), oral health impact profile (OHIP), and periodontal parameters (bleeding on probing and plaque index). Results: A total of 46 patients (16 males and 30 females) with 124 implants were included in this study. Twenty-five implant-retained overdentures were delivered on 53 unsplinted implants, while the other 21 patients received an implant-supported overdentures and the implants were splinted. At the five-year follow-up examination, one implant and one prosthesis failed in the unsplinted group, resulting in a cumulative survival rate of 97.8% at the patient level. Two minor technical complications were experienced. Conclusions: Implant overdenture retained or supported by ball attachment systems showed high implant and prosthetic survival and success rates. A low number of complications, high patient satisfaction, and successful biological parameters were experienced in the mid-term follow-up. Data need to be confirmed by further randomized trials. [ABSTRACT FROM AUTHOR]