Oblique Configuration Research Articles

MP42-01 SCATTER RADIATION EXPOSURE TO THE SURGICAL TEAM DURING SUPINE AND PRONE PERCUTANEOUS NEPHROLITHOTRIPSY

You have accessJournal of UrologyImaging/Radiology: Uroradiology II (MP42)1 Apr 2020MP42-01 SCATTER RADIATION EXPOSURE TO THE SURGICAL TEAM DURING SUPINE AND PRONE PERCUTANEOUS NEPHROLITHOTRIPSY David Chapman*, Shubha De, and Devin Demitor David Chapman*David Chapman* More articles by this author , Shubha DeShubha De More articles by this author , and Devin DemitorDevin Demitor More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000000891.01AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Radiation is central to diagnostic and therapeutic procedures in Urology. Intraoperative exposure to patients and the care team continues to be a concern. Many strategies help reduce radiation exposure during percutaneous nephrolithotomy (PCNL), however, little has been studied in the contribution of patient positioning and C-arm orientation. The aim of this study was to compare the radiation exposure to the surgical team during supine and prone positions with common C-arm configurations. METHODS: A benchtop experiment was conducted using a Siemens C-arm, anthropomorphic model (80kg human torso) and a 180cc ionization chamber (RadCal Accu Gold Touch) to directly measure radiation scatter (mR/min) to the healthcare team during different configurations of the C-arm (AP, 150 oblique, lateral) for prone and supine (Bart’s free flank 150 decubitus) PCNL. Exposure was measured using regular and high dose fluoroscopy settings, for all personnel [radiation technologist (XRT), scrub nurse (SN), urologist (URO), and anesthesiologist (ANS)] for six c-arm orientations at eye and gonad level. RESULTS: Standard radiation dose was defined as detected scatter with the patient in traditional proned position, and c-arm in AP (eyes: URO 0.59, ANS 0.00, SN 0.00, XRT 0.00 mR/min; gonads URO 1.3, ANS 0.00, SN 0.22, XRT 0.00 mR/min). With the c-arm in lateral orientation and patient in supine, the average dose increased by 6.49 to 21.13 times compared to the oblique and AP configuration, respectively (see figure 1). When dose reduction methods were employed: positioning the surgical team opposite to the image intensifier, exposure was reduced by 3.14-3.58 times, whereas rotating the C-arm over the table (into lateral position) reduced exposure by 1.49-1.46 times (as compared to standard ‘under the table’ lateral positioning). CONCLUSIONS: Radiation is of increasing concern and current guidelines do not recommend physical strategies of dose reduction. This study highlights the ability for a surgical team to drastically alter radiation exposure by considering positioning as part of the contributing factors. Knowing relative exposure increases may empower surgeons to choose alternative orientations to accomplish tasks while minimizing scatter. Source of Funding: None © 2020 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 203Issue Supplement 4April 2020Page: e603-e603 Advertisement Copyright & Permissions© 2020 by American Urological Association Education and Research, Inc.MetricsAuthor Information David Chapman* More articles by this author Shubha De More articles by this author Devin Demitor More articles by this author Expand All Advertisement PDF downloadLoading ...

Management Of An Additional Trochanteric Fracture On Previously Femoral Shaft Fracture : An Atypical Case Report

Background. Ipsilateral hip and femoral shaft fractures are rare injuries and difficult to manage. Ipsilateral intertrochanteric and femoral shaft fractures occupy one fourth approximately of these injuries. Predominantly, male patients in the fourth decade of their life are suffering these fractures following polytraumatization. A high energy trauma known as the mechanism of these injury, in contrast to low energy trauma or pathological fractures. Method. We present a case of 37 years old male with an additional ipsilateral trochanteric fracture on previously femoral shaft fracture. The patient suffered an open fracture of right femoral shaft with oblique configuration and displacement of the fracture segment. Patient and family refused to go for surgery. Ten months after the initial injury, patient had a motor vehicle accident for the second time and later was brought immediately to our center. Patient underwent plate and screw fixation for the femoral shaft fracture. The surgery worked well and postoperative the patient routinely attend the rehabilitation center. Results. PFNA-long can stabilize and fix both fractures simultaneously compared with plate combinations. Operating time was shorter and perioperative blood loss less in the PFNA-long group Conclusion. In ipsilateral intertrochanteric and femoral shaft fracture, a combination between proximal femoral nail anti-rotation and conservative plate and screw is an option to consider. The benefit from this option include shorter operation time and less intraoperative blood loss.

A Modification of the Fibular Osteotomy for Total Ankle Replacement Through the Lateral Transfibular Approach.

One disadvantage of lateral transfibular total ankle arthroplasty is the rate of symptoms related to the implant and wound issues requiring implant removal in association with the traditional fibular osteotomy. In the present study, lateral total ankle arthroplasty involving the traditional short oblique fibular osteotomy was compared with arthroplasty involving a long oblique osteotomy (the Foot & Ankle Reconstruction Group osteotomy). We retrospectively reviewed all primary lateral total ankle arthroplasties that had been performed by a single surgeon from May 2013 to October 2016 and had a minimum of 2 years of follow-up. Clinical assessment included patient demographics, wound complications, the need for implant removal, the pain score on a visual analog scale, the American Orthopaedic Foot & Ankle Society score, and the Short Form-12 Mental and Physical Component Summary scores. Weight-bearing radiographs were used to assess tibiotalar alignment, implant alignment, and fibular osteotomy healing. One hundred and fifty-nine total ankle arthroplasties were identified. The traditional short fibular osteotomy was used in 50 ankles, and the long oblique osteotomy was used in 109. The rate of survival of the tibial and talar components of the ankle replacements was 100%, and there were no osteotomy nonunions. There was improvement in all clinical parameters, with no significant difference between the 2 groups. Radiographs showed excellent arthroplasty alignment at all time points, with no significant difference between the groups. There was a significant difference in the rates of wound dehiscence (p = 0.011) and fibular implant removal (p < 0.0001), with the long oblique osteotomy having lower rates of both (2.8% and 2.8%, respectively) compared with the short oblique osteotomy (14% and 28%, respectively). In total ankle arthroplasty, modification of the traditional short oblique fibular osteotomy to a long oblique configuration provided excellent 2-year survival rates with good clinical and radiographic outcomes and decreased rates of wound complications and symptoms related to the fibular implant. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Sodium ion storage performance of magnetron sputtered WO3 thin films

WO3 thin film electrodes were successfully prepared by magnetron sputtering (MS) deposition under an oblique angle configuration (OAD). Intercalation of Na ions in the tungsten oxide layers has been studied using electrochemical techniques. Sample characterization before and after sodium intercalation has been carried out by Raman, XPS and XRD measurements. ToF-SIMS analysis has been also performed in order to analyze the element depth profiles along the electrode thickness. Electron microscopy evaluation of the cross section confirms the porous structure of the coatings. Batteries integrating these WO3 electrodes have a discharge capacity of 120 mA h g−1 at the initial cycles and show an adequate capacity retention upon 300 cycles. The WO3-OAD thin-films are proposed as promising electrodes for Na-ion batteries.

Monitoring and Computation of the Volumes of Stockpiles of Bulk Material by Means of UAV Photogrammetric Surveying

The monitoring and metric assessment of piles of natural or man-made materials plays a fundamental role in the production and management processes of multiple activities. Over time, the monitoring techniques have undergone an evolution linked to the progress of measure and data processing techniques; starting from classic topography to global navigation satellite system (GNSS) technologies up to the current survey systems like laser scanner and close-range photogrammetry. Last-generation 3D data management software allow for the processing of increasingly truer high-resolution 3D models. This study shows the results of a test for the monitoring and computing of stockpile volumes of material coming from the differentiated waste collection inserted in the recycling chain, performed by means of an unmanned aerial vehicle (UAV) photogrammetric survey and the generation of 3D models starting from point clouds. The test was carried out with two UAV flight sessions, with vertical and oblique camera configurations, and using a terrestrial laser scanner for measuring the ground control points and as ground truth for testing the two survey configurations. The computations of the volumes were carried out using two software and comparisons were made both with reference to the different survey configurations and to the computation software.

Plate impact investigation of the dynamic response of commercial tungsten carbide under shock-induced compression and combined compression-and-shear loading

This article presents results from a series of plate-impact experiments designed to study dynamic response of commercial purity (99.6%) tungsten carbide (WC) under shock-induced normal compression and simultaneous compression-and-shear stress wave loading. The normal shock compression experiments utilize a heated WC flyer plate which impacts a WC target at room temperature, enabling inelastic response of the WC target plate as well as the elevated temperature shock-impedance of the heated WC flyer plate to be probed simultaneously. The measured normal particle velocity profiles at the free surface of the WC target plate exhibit an elastic precursor, which corresponds to a longitudinal stress of ∼5.9–6.2 GPa, and decreasing particle velocity levels in the shocked state with increasing temperature of the WC flyer. The shock impedance of the heated WC flyer is estimated to decrease from 1.05 × 108 to 8.23 × 107 kg/m2s over the temperature range 23–600°C. The simultaneous compression-and-shear loading experiments are conducted using a symmetric oblique plate-impact experimental configuration with progressively increasing angles of inclination (5°, 10°, and 22°), resulting in increasing shear to longitudinal stress ratios upon impact in the WC flyer and target plates. The measured longitudinal and transverse components of the free surface particle velocity in experiments with inclination angles of up to 10° and impact velocities ∼100 m/s (corresponding to shear and longitudinal stress levels of 0.5 GPa and 4.5 GPa, respectively), coincide well with their corresponding elastic particle-velocity predictions. However, the free-surface normal particle velocity profiles for experiments conducted at an oblique impact angle of 22° (corresponding to shear stresses ∼1.3 GPa and longitudinal stress of ∼4.9 GPa) are remarkably different and exhibit a sudden increase in particle velocity from their plateau levels reminiscent of failure waves observed by other investigators in soda lime glass and silicon carbide (SIC-B). The new normal particle velocity level, after the arrival of the recompression/re-acceleration signal, exceeds the magnitude of the impact velocity, suggesting failure of the WC target plate during the stress wave loading process. The relatively large undulations present in the measured free-surface transverse particle velocity profiles provide further evidence for the heterogeneous brittle failure processes in WC under the resulting simple-shear state of stress, and is used to provide estimates for the critical range of simple-shear loading that can initiate catastrophic failure (fracture) in pure WC.

Light-sheet microscopy in the near-infrared II window.

Deep-tissue three-dimensional (3D) optical imaging of live mammals with high spatiotemporal resolution in non-invasive manners has been challenging due to light scattering. Here, we developed near-infrared II (NIR-II, 1000–1700 nm) light sheet microscopy (LSM) with excitation and emission up to ~ 1320 nm and ~ 1700 nm respectively for optical sectioning through live tissues at ~ 750-μm penetration depth without any invasive surgery. Suppressed light scattering allowed imaging at ~ 2 mm depth in glycerol-cleared brain tissues. NIR-II LSM in normal and oblique configurations enabled in vivo imaging of live mice through intact tissue, revealing abnormal blood flow and T cell motion in tumor microcirculation and mapping out programmed-death ligand 1 (PD-L1) and programmed cell death protein 1 (PD-1) in tumors with cellular resolution. 3D imaging through intact mouse head resolved vascular channels between skull and brain cortex, and monitored recruitment of macrophages/microglia to traumatic brain injury site post injury.

Use of Selective Laser Melting for Manufacturing the Porous Stack of a Thermoacoustic Engine

In this study the authors investigate the possibility of using Selective Laser Melting (SLM) to manufacture the porous element (stack) of a thermoacoustic engine. Two stacks, provided with different internal geometries but with the same hydraulic radii, have been produced: one with parallel plates and one with a new, oblique pin array configuration. The pin array stacks provide smaller amount of viscous losses during the thermal to acoustic power conversion when working fluids with Pr &lt; 1, e.g. air. Furthermore, the oblique configuration is designed to reduce the heat transmission from the hot to the cold surface of the stack, thus to achieve more easily the temperature gradient for the onset of the thermoacoustic phenomenon. In general, the pin array configurations are difficult to manufacture with conventional technologies. However, the SLM provides precise control of the features of the printed object, thus allowing to objectively compare the behavior of the two stacks. To this aim, the temperature gradient between the hot and cold faces of the stacks and the corresponding sound pressure levels measured at 15 cm from the open end of the engine are measured and compared.

On the optimal choice of fibre orientation angle in off-axis tensile test using oblique end-tabs: Theoretical and experimental studies

Shear strength evaluation in composite materials still remains a not fully solved problem. One of most promising proposals to characterise a material in shear by means of a simple tensile test is the off-axis tension test with oblique end-tabs whose inclination coincides with that of the longitudinal isodisplacement lines. This end-tab configuration presents an essential difficulty since the tab angle depends on the material properties including the shear modulus G12, which is one of the values to be obtained from off-axis tension tests.In the present work, the study of the most suitable fibre orientation for the performance of off-axis tests under an oblique tabs configuration has been addressed. An analytical study on the dependence of the tab angle ϕ on both the fibre orientation θ and the material properties E11, E22, ν12 and G12 has been carried out, the quotient G12/E11 being identified as the parameter that controls the evolution of the tab angle.The influence of deviations in the tab angle on the stress state near the corners of specimen has been analysed by means of a novel study of the nominal singular stress state at these points. The results of this study show that negative deviations in the angle of the tabs contribute to decrease the severity of the stress state at the corner, whereas positive deviations contribute to increase the order of the stress singularity. Additionally, the range of fibre orientations in which the evaluation of shear strength S is feasible has been determined, i.e., the effect of σ12 in the failure is clearly dominant versus the effect of the rest of the stress-state components.In the experimental part of this work, four different fibre orientation angles (5°, 10°, 15° and 20°) have been considered to perform the off-axis tension test under oblique end-tabs configuration. The experimental results of these tests show that only for 10° fibre orientation angle the majority of specimens fail at the central zone under a uniform stress state. Finally, for a fibre orientation angle θ = 10°, specimens with induced positive deviations in tab angle of +3° and +7° have been tested, it being observed that all the failures appears at the end of specimens.On the basis of both theoretic and experimental results, the optimal fibre orientation angle to use in the tests is θ = 10°. The tab angle must be evaluated on the basis of an estimation of the material properties (quotient G12/E11), it being recommendable, in case of ignoring the value of G12, to use a tab angle lesser than the theoretical value to avoid positive deviations.

CFD Study of Unsteady Flow Through Savonius Wind Turbine Clusters

The interaction between Savonius vertical axis wind turbine clusters installed in far or close proximity can devalue or enhance the output power of single Savonius vertical axis wind turbines. In this paper, the effect of spatial distribution is studied for the development of efficient Savonius vertical axis wind turbine farms. Numerical simulations are performed for a single Savonius wind turbine, sets of two rotating turbines in three different configurations (aligned, parallel and oblique configurations), and clusters of three rotating turbines, using five separation distances of 0.25D, 0.5D, 1D, 1.5D and 2D, making a total of twenty-two test scenarios. The commercial CFD software Fluent 15.0 is used for the numerical study. The torque and power coefficient results of single Savonius turbine are compared and validated against experimental and numerical data based on the literature review. The results showed that there was a combined effect related to the inter-turbine distance and the output power. This combined effect showed an efficient three Savonius turbine cluster having an average power coefficient 3 times higher than an isolated turbine. Best Savonius farm efficiency and high output power could be obtained by considering, at least, these two parameters.

Environmentally Tight TiO2–SiO2 Porous 1D‐Photonic Structures

AbstractAlthough thin film porosity is the basis of many optical sensors, it can be deleterious for a stable optical behavior of passive optical elements due to the condensation of water and other vapors in their pores. This paper proposes a new strategy for the magnetron sputtering (MS) fabrication of environmentally tight SiO2–TiO2 porous multilayers. Thin films of these two oxides deposited in an oblique angle configuration (MS‐OAD) present a nanocolumnar and highly porous nanostructure and, as a consequence, experience significant changes in their optical properties when exposed to water vapor. Similarly, the optical properties of Bragg reflectors and Bragg microcavities made of the stacking of porous and compact SiO2 and TiO2 thin films experience reversible changes when these 1D‐photonic structures are exposed to water pressure. A key finding of this work is that a very thin capping layer of SiO2 deposited on the surface of porous SiO2 films in the stack, at the interlayer between the two oxides, efficiently seals the pores making the photonic structures environmentally tight. This capping layer approach is a useful strategy to incorporate porosity as an additional parameter to design the optical behavior of planar photonic structures while preserving optical and environmental stability.

Three-dimensional kinematic corridors of the head, spine, and pelvis for small female driver seat occupants in near- and far-side oblique frontal impacts

Objectives: Analyses of recent automotive accident data indicate an increased risk of injury for small female occupants compared to males in similar accidents. Females have been shown to be more susceptible to spinal injuries than males. To protect this more vulnerable population, advanced anthropomorphic test devices (ATDs) and computer human body models are being developed and require biofidelity curves for validation. The aim of this study is to generate female-specific 3D kinematic corridors in near- and far-side oblique frontal impacts for the head, spine, and pelvis.Methods: Eight specimens were procured and prescreened for mass, stature, and quantitative computed tomography bone mineral density and preexisting injuries to minimize biologic variability. Sets of 4 noncolinear retroreflective targets were placed on the back of the head; dorsal spine at T1, T8, and L2; and posterior sacrum. Instrumented computed tomography scans were obtained to measure the orientation and position of the markers relative to anatomic fiducials. The specimens were placed on a buck representative of a generic automotive driver’s seat environment designed to minimize lower-extremity and pelvic motion. The buck was oriented such that the buck centerline was seated 30° from the impact vector in either a near- or far-side oblique frontal configuration. Preposition of the occupant was specified to the 50th percentile male H-point location, thigh and tibial angles, and torso angle. Impact was delivered via a servo-acceleration sled to the base of the buck with a 30 km/h 9 g trapezoidal pulse. Occupants were restrained by a standard 3-point belt that had a custom load-limiter device set to 2 kN at the D-ring side of the shoulder belt. Target motion was recorded at 1 kHz using a 3D optical motion capture system. Anatomic motion of the head, spine, and pelvis was calculated relative to the seat, and the average response was determined from 4 near-side and 4 far-side tests. The borders of the corridor were determined by calculating a standard deviational ellipse in the x, y, and z planes at each time step.Results: Plots of the biofidelity corridors for near- and far-side tests are shown in planes parallel to the seat from the lateral, rear, and overhead directions. Averaged peak excursions in the fore/aft and lateral directions are compared for the near- and far-side corridors. Near-side female and male tests are similarly compared.Conclusions: In general, average peak excursions were greater in the far-side configuration than in the near-side configuration. Peak excursion results compared well with similar tests conducted on male postmortem human subjects (PMHS). The kinematic corridors developed in the current study serve as a set of biofidelity corridors for the development of current and future physical and computational surrogates.

Sliding mode control design for oblique wing aircraft in wing skewing process

When the wing of Oblique Wing Aircraft (OWA) is skewed, the center of gravity, inertia and aerodynamic characteristics of the aircraft all significantly change, causing an undesirable flight dynamic response, affecting the flying qualities, and even endangering the flight safety. In this study, the dynamic response of an OWA in the wing skewing process is simulated, showing that the three-axis movements of the OWA are highly coupled and present nonlinear characteristics during the wing skewing. As the roll control efficiency of the aileron decreases due to the shortened control arm in an oblique configuration, the all-moving horizontal tail is used for additional roll and the control allocation is performed based on minimum control energy. Given the properties of pitch-roll-yaw coupling and control input and state coupling, and the difficulty of establishing an accurate aerodynamic model in the wing skewing process due to unsteady aerodynamic force, a multi-loop sliding mode controller is formulated by the time-scale separation method. The closed-loop simulation results show that the asymmetric aerodynamics can be balanced and that the velocity and altitude of the aircraft maintain stable, which means that a smooth transition is obtained during the OWA’s wing skewing.

Importance of electrode position for the distribution of tumor treating fields (TTFields) in a human brain. Identification of effective layouts through systematic analysis of array positions for multiple tumor locations.

Tumor treating fields (TTFields) is a new modality used for the treatment of glioblastoma. It is based on antineoplastic low-intensity electric fields induced by two pairs of electrode arrays placed on the patient’s scalp. The layout of the arrays greatly impacts the intensity (dose) of TTFields in the pathology. The present study systematically characterizes the impact of array position on the TTFields distribution calculated in a realistic human head model using finite element methods. We investigate systematic rotations of arrays around a central craniocaudal axis of the head and identify optimal layouts for a large range of (nineteen) different frontoparietal tumor positions. In addition, we present comprehensive graphical representations and animations to support the users’ understanding of TTFields. For most tumors, we identified two optimal array positions. These positions varied with the translation of the tumor in the anterior-posterior direction but not in the left-right direction. The two optimal directions were oriented approximately orthogonally and when combining two pairs of orthogonal arrays, equivalent to clinical TTFields therapy, we correspondingly found a single optimum position. In most cases, an oblique layout with the fields oriented at forty-five degrees to the sagittal plane was superior to the commonly used anterior-posterior and left-right combinations of arrays. The oblique configuration may be used as an effective and viable configuration for most frontoparietal tumors. Our results may be applied to assist clinical decision-making in various challenging situations associated with TTFields. This includes situations in which circumstances, such as therapy-induced skin rash, scar tissue or shunt therapy, etc., require layouts alternative to the prescribed. More accurate distributions should, however, be based on patient-specific models. Future work is needed to assess the robustness of the presented results towards variations in conductivity.

Sensing and biosensing with screen printed electrodes modified with nanostructured nickel oxide thin films prepared by magnetron sputtering at oblique angles

This work reports about the sensing and biosensing applications of a novel screen printed electrode (SPE) modified by nanostructured nickel oxide thin films obtained by reactive magnetron sputtering under an oblique angle configuration. Using these films as electrodes we demonstrate their ability to detect hydrogen peroxide under neutral pH conditions. Furthermore, as a proof-of-concept, NiO-modified SPEs have been developed and their cholesterol biosensing properties determined by cyclic voltammetry and chronoamperometry.

Influence of lateral dimensions, obliquity, and target thickness toward the efficiency of unconfined ceramic tiles for the defeat of rod penetrators

In a recent study, the authors have shown that unconfined finite-thickness ceramic tiles can be used for a mass-efficient defeat of long-rod high-density projectiles under perpendicular impact conditions [Int. J. Impact Engineering 95, 54–60; 2016]. The present paper extends this work in several directions. Firstly, the influence of the lateral tile dimensions is investigated. Secondly, the effects of target obliquity at constant target design are taken into account. Thirdly, the effects of target obliquity at constant line-of-sight thickness are considered. All three aspects are related to the total target weight necessary for a full defeat of the projectile. Based on a separate investigation of those three aspects, the combined effect of tile dimensions, buffer thickness, and obliquity on the protective properties is analyzed. As a starting point, prior data is reviewed and further data supporting earlier published results is presented. It is concluded, that the basic defeat mechanisms persist for smaller lateral dimensions and partly also for oblique targets. However, they gradually diminish and it does not appear promising to compensate reduced ceramic tile thickness by obliquity. Rather, the mass efficiency is reduced for oblique impact configurations.

Experiments on wake structures behind a microparticle in a magnetized plasma flow

The wake behind a spherical microparticle in a magnetized ion flow is studied experimentally by analyzing the arrangement of a pair of particles. It is shown that there are two stable particle arrangements at intermediate magnetic inductions, whereas only oblique (horizontal) particle configurations are found at the highest magnetic field. Self-consistent collisional molecular dynamics simulations of the particle system show that the underlying mechanism of these arrangements is the weakening of attractive wake forces by the increasing magnetic field. Plasma instabilities provide a trigger for the onset of the transition between the two different arrangements. Furthermore, the course of the transition is qualitatively explained by the charge variation of the downstream particle in the wake of the upstream particle. In addition, a thorough analysis of the sheath by means of particle-in-cell simulations in combination with particle resonance measurements yields consistent values of the particle mass and charge, as well as the levitating electric field and ion flow velocity.

Improving the fabrication uniformity of ZnO nanowire UV sensor by step-corner growth mode

Uniformity in mass-fabrication of nanostructured device is important for its practical application. In this paper, we developed a step-corner growth mode to on-chip fabricate uniform oblique-bridged ZnO nanowire UV sensor. By strictly controlling the microelectronic processing including photolithography and magnetron sputtering procedures during the seed layer deposition and electrode fabrication, ZnO NW array could nucleate at the upper step-corner of the seed layer due to the high catalytic activities at the surface steps and kinks, and then grow in a distribution of circular sector to form an oblique bridging configuration, which guaranteed the device performance and uniformity at the same time. For the within-chip uniformity, in a 4 × 4 sensor array that randomly chosen under the 365 nm UV light of 2.5 mW/cm2 and at the bias voltage of 1 V, the light-to-dark current ratio all kept in the level of 106 with the average value of 1.84 × 106. There were 75% of them in the range of 1.1 × 106 ~ 3 × 106. The detectivity all kept in the level of 1015Jones with the average value of 3.53 × 1015Jones. There were 75% of them in the range of 2 × 1015 ~4 × 1015Jones. For the chip-to-chip uniformity, in 12 packaged devices that randomly chosen from three fabrication lots, the light-to-dark current ratio all kept in the level of 106 with the average value of 2.70 × 106. There were 75% of them in the range of 1 × 106~ 3 × 106. The detectivity all kept in the level of 1015Jones with average value of 3.69 × 1015Jones. There were 75% of them in the range of 1 × 1015 ~ 4 × 1015Jones. The uniformity would deteriorate if the step height of seed layer was short, because NW would nucleate at the lower corner of the step and difficult to form the oblique bridge. Fabrication uniformity was also influenced by the step exposure degree, the compactness of the seed layer and the flatness of the substrate.

Pliocene seismic stratigraphy and deep‐water sedimentation in the Qiongdongnan Basin, South China Sea: Source‐to‐sink systems and hydrocarbon accumulation significance

This study uses high‐quality two‐dimensional (2‐D) seismic and well data to analyse seismic stratigraphy and deep‐water Pliocene sediments in the Qiongdongnan Basin (QDNB), South China Sea. Eight major seismic facies were identified based on the amplitude, continuity, configuration, and external geometry of seismic reflections. Among them, sigmoid progradational configurations, oblique progradational configurations, mound‐shaped chaotic configurations, and mound‐shaped hummocky configurations are newly identified seismic facies indicative of provenance and water system significance. They were interpreted as a Pliocene‐aged eastern shelf‐edge delta, a western shelf‐edge delta, and eastern and western submarine fans in QDNB. Consequently, two sets of Pliocene shelf‐edge delta‐continental slope canyon‐submarine fan systems were established in the QDNB. From the approximately NNW–SSE progradation of the shelf‐edge delta, the characteristics of the approximately ENE–WSW distributed continental slope system, and the definition of a source‐to‐sink system, as well as previous heavy mineral research, we conclude the existence of two Pliocene sources from Hainan Island in the northern QDNB, corresponding to the Lingshui River and Wanquan River. Two independent and complete source‐to‐sink systems (S2S‐2, S2S‐3) were distinguished from the northern Hainan Island to the basin area. S2S‐2 is located in the western QDNB, which includes the Lingshui River‐western shelf‐edge delta‐continental slope canyon‐submarine fan. This source‐to‐sink system has more sand‐rich material and better reservoir conditions than S2S‐3 in the eastern basin, predominantly due to a higher quality granite parent rock, abundant provenance, and a large‐scale delta and submarine fan.

Frontal and oblique crash tests of HIII 6-year-old child ATD using real-world, observed child passenger postures

ABSTRACTObjective: The aim of this study was to evaluate the consequences of frontal and oblique crashes when positioning a Hybrid III (HIII) 6-year-old child anthropometric test device (ATD) using observed child passenger postures from a naturalistic driving study (NDS).Methods: Five positions for booster-seated children aged 4–7 years were selected, including one reference position according to the FMVSS 213 ATD seating protocol and 4 based on real-world observed child passenger postures from an NDS including 2 user positions with forward tilting torso and 2 that combined both forward and lateral inboard tilting of the torso. Seventeen sled tests were conducted in a mid-sized vehicle body at 64 km/h (European New Car Assessment Programme [Euro NCAP] Offset Deformable Barrier [ODB] pulse), in full frontal and oblique (15°) crash directions. The rear-seated HIII 6-year-old child ATD was restrained on a high-back booster seat. In 10 tests, the booster seat was also attached with a top tether. In the oblique tests, the ATD was positioned on the far side. Three camera views and ATD responses (head, neck, and chest) were analyzed.Results: The shoulder belt slipped off the shoulder in all ATD positions in the oblique test configuration. In full frontal tests, the shoulder belt stayed on the shoulder in 3 out of 9 tests. Head acceleration and neck tension were decreased in the forward leaning positions; however, the total head excursion increased up to 210 mm compared to te reference position, due to belt slip-off and initial forward leaning position.Conclusions: These results suggest that real-world child passenger postures may contribute to shoulder belt slip-off and increased head excursion, thus increasing the risk of head injury. Restraint system development needs to include a wider range of sitting postures that children may choose, in addition to the specified postures of ATDs in seating test protocols, to ensure robust performance across diverse use cases. In addition, these tests revealed that the child ATD is limited in its ability to mimic real-world child passenger postures. There is a need to develop child human body models that may offer greater flexibility for these types of crash evaluations.