Lateral Zone Research Articles

Improving image accuracy of ambient noise data by temporary seismic arrays at different observation periods

When using ambient noise data to invert velocity and anisotropic structures, the two-station inter-correlation method requires synchronous stations. If there are multiple temporary seismic arrays with different observation periods in the study area, the seismic arrays are usually used selectively. This paper takes the Sanjiang lateral collision zone as an example, and utilizes the ambient noise data of multiple temporary seismic arrays at different observation periods to improve the accuracy of regional velocity structure and anisotropy by anchoring permanent seismic stations. In this paper, notable enhancements in S-wave velocity and azimuthal anisotropy imaging accuracy are achieved by integrating data from three temporary seismic arrays (SJ-Array, SL-Array, and ChinArray-I) with the permanent seismic network. The imaging resolutions for the S-wave velocity and azimuthal anisotropy above 40 ​km are 0.4° ​× ​0.4° and 0.5° ​× ​0.5°, respectively. In the region of the most concentrated array coverage, the imaging resolution of S-wave velocity can reach 0.33° ​× ​0.33° at depths of less than 30 ​km. These findings underscore the significant improvement in deep structure imaging accuracy by the synergistic integration of ambient noise data from multiple temporary seismic arrays.

Heat transfer enhancement of water flow over a heating flat plate using 20 kHz ultrasonic waves irradiated from submerged horn-type transducer

The enhancement of heat transfer of water flow over a flat plate under 20 kHz ultrasound irradiated from a submerged horn-type transducer was investigated experimentally in a water tunnel. To examine the ultrasonic effects, the transducer emitted waves perpendicular to the mainstream direction, and the freestream velocity varied between 0.12 and 0.17 m/s. The transducer position was fixed at 0.45 m from the plate leading edge in a streamwise direction. This position was altered in a heightwise direction as dimensionless heightwise distances (Z) that were divided by the diameter of the horn-tip transducer (12 mm) at 1.5, 3.0, and 4.5 from the plate surface. A hot film sensor and thermochromic liquid crystals coated on the test surface were used to demonstrate the hydrodynamic and thermal characteristics, respectively. The maximum temperature reduction of 3.5 °C was observed in the case of Z = 1.5. By employing a horn-type transducer, the acoustic jet and cavitation phenomena played a key role in destabilizing the thermal and velocity boundary layers, which resulted in a decrease in surface temperature. The incident wave shape was triangular, with an enlarging lateral zone along the flow stream. When the waves were released at Z = 1.5, the local Nusselt number was increased up to 2.55 compared to without waves. Under ultrasonic effects, the near-wall flow velocity was detected to be decreasing upstream prior to the incident zone while increasing in the incident region. When waves existed, the highest turbulent intensity was up to 29 times more intense than it was in the absence of waves. Furthermore, a predictive formula for the Nusselt number with ultrasound was established depending on the local Reynolds number and the distance between the ultrasonic source and test surface.

The peptide GOLVEN10 alters root development and noduletaxis in Medicago truncatula.

The conservation of GOLVEN (GLV)/ROOT MERISTEM GROWTH FACTOR (RGF) peptide encoding genes across plant genomes capable of forming roots or root-like structures underscores their potential significance in the terrestrial adaptation of plants. This study investigates the function and role of GOLVEN peptide-coding genes in Medicago truncatula. Five out of fifteen GLV/RGF genes were notably upregulated during nodule organogenesis and were differentially responsive to nitrogen deficiency and auxin treatment. Specifically, the expression of MtGLV9 and MtGLV10 at nodule initiation sites was contingent upon the NODULE INCEPTION transcription factor. Overexpression of these five nodule-induced GLV genes in hairy roots of M. truncatula and application of their synthetic peptide analogues led to a decrease in nodule count by 25-50%. Uniquely, the GOLVEN10 peptide altered the positioning of the first formed lateral root and nodule on the primary root axis, an observation we term 'noduletaxis'; this decreased the length of the lateral organ formation zone on roots. Histological section of roots treated with synthetic GOLVEN10 peptide revealed an increased cell number within the root cortical cell layers without a corresponding increase in cell length, leading to an elongation of the root likely introducing a spatiotemporal delay in organ formation. At the transcription level, the GOLVEN10 peptide suppressed expression of microtubule-related genes and exerted its effects by changing expression of a large subset of Auxin responsive genes. These findings advance our understanding of the molecular mechanisms by which GOLVEN peptides modulate root morphology, nodule ontogeny, and interactions with key transcriptional pathways.

Flow around single and two tandem rectangular cylinders with various single-side fairings

The shape of single-side wind fairing, which is the longitudinal triangular prism that tailors the outer side of a bridge deck, is key to the aerodynamic performances of double streamlined box girders used in long-span bridges. Uniform flow past single and double 4:1 rectangular cylinders with various single-side fairings are investigated using large-eddy simulation at a Reynolds number of 1.1 × 104. Various fairing nose angles and heights are compared. The wind loading and flow characteristics of the cylinders are discussed. The upstream fairing shows a larger reduction of mean drag and fluctuating lift on double cylinders than on a single cylinder. The fairing nose angle has a stronger influence on the wind loading than the nose height. By adding the fairing, sharpening the fairing nose, or lifting the fairing nose, the lateral recirculation zones are shortened while the rear recirculation zone barely changes, leading to different influences on the surface pressure. The upstream fairing is effective in reducing the vertical range and complexity of vortex structures around single and double cylinders.

Histological alterations as a recommended biomarker in the mussel Mytilus platensis (Bivalvia, Mytilidae) to study anthropic impact on seaports

Toxic effects of trace metals on digestive gland and gill cytoarchitecture were studied in the mussel Mytilus platensis after metal detection in the environment. Mussels were collected from the Port of San Antonio Este and from a reference site called Isla Mejillón, both in Rio Negro province (Argentina). Histological techniques, morphometrical analysis and lipofuscin detection with Nile blue method were performed. Mussels from the seaport presented dilated hemolymphatic vessels with numerous hemocytes in the gill filaments and fused filaments in the frontal zone. Morphometric analysis of the gill filaments showed an increase in the epithelial thickness of the lateral zone that bears cilia, and we infer that water filtering might be affected. The sublateral zone was also thickened, probably interfering with gas exchange. A reduction in the abfrontal zone epithelial thickness was also noticed, so water pumping, lubrication and cleaning of the gills might be impaired. Digestive glands of seaport mussels accumulated lipofuscin granules within the digestive cells, accounting for lipid and protein peroxidation. The observed histological alterations in gill and digestive gland in mussels from North Patagonia seaport are relevant findings to be considered as biomarkers of effect after exposure to metals.

Assessment of the solitary wave attenuation through pervious concrete breakwater

Breakwaters are coastal structures typically used to protect shorelines from coastal erosion by providing wave energy attenuation and reflecting amounts of wave currents. Traditional breakwaters made of impervious materials can have a significant environmental impact, disrupting the coastal ecosystem and altering natural wave patterns. In general, permeability has become an acquainted characteristic since it directly influences the interaction between the structure, the coastal zone behind it, and the lateral zone without structural protection, which makes pervious concrete a sustainable alternative to traditional concrete. In this study, pervious concrete is utilised as a permeable breakwater considering the influence of permeability introduced to deliver ecological friendliness defence for shorelines. A physical experiment was used to evaluate four models of structures that varied in porosity in order to study the physical properties and then analyse the performance of the pervious concrete breakwater over the solitary wave impact. Subsequently, the hydrodynamic scattering coefficient is analysed by considering changes in physical parameters. The results indicated that pervious concrete breakwater (PCB) could effectively work in the case of emergence due to the increased interaction between wave and structure. PCBs can effectively reduce wave reflection and increase wave transmission, with the magnitude of these effects increasing with porosity. The result indicated the potentiality of PCB to serve as a feasible alternative to traditional breakwaters for a prospective coastal protection structure by reducing the environmental impact as PCBs allow for the passage of water and other marine organisms, which can help maintain the health of coastal ecosystems. Finally, the structure of PCBs, which can be prefabricated, could reduce the complexity and time of installation, making them a cost-effective solution for coastal protection.

Lateral Viewing Zone of Depth-Fused 3D (DFD) Display by Use of Aerial Image in Front

Lateral Viewing Zone of Depth-Fused 3D (DFD) Display by Use of Aerial Image in Front

Abstract 14117: Home Operated Ultrasound Exam for Detection of Worsening Heart Failure

Introduction: Acute Decompensated Heart Failure (ADHF) is associated with a high degree of morbidity and mortality. Dynamic lung ultrasound artifact called B-lines directly correlate with pulmonary vascular congestion (PVC) and can be seen on a limited lung ultrasound. Hypothesis: We assessed the ability of a recently hospitalized patient with ADHF to self-perform a lung ultrasound using a hand-held ultrasound and store images for physician interpretation. Methods: This was a prospective observational convenience sample of patients with known chronic heart failure admitted to an urban academic tertiary care center. The patient was educated on a 6 lung-zone image protocol, how to use the cloud archival system, and given a hand-held ultrasound transducer and iPad. The patients were asked to upload images three times a week, for 3 weeks. A B-line score for each interpretable lung zone was calculated. Results: Fifteen patients were enrolled, all of whom completed 7 or more scans. Average patient age was 60 years (range: 28- 86 years), 73% male, 60% white, and 47% obese. Five patients had ejection fraction >50%, and average length of hospital stay was 6.3 days. Of the 792 potential images, 784 were obtained (99%) and 637 (81%) were interpretable. The right upper zone was most often interpretable (97%), whereas the left lateral zone was least (70%). Median patient B line score when indexed to 6 interpretable scans was 3.00. Indexed B line scores are shown for all 15 patients (Figure 1). Patient survey data identified the left lateral zone as the most challenging to obtain. Conclusions: This pilot study shows that patients with ADHF can be taught how to use a hand-held portable ultrasound device and obtain and upload lung ultrasound images to a cloud. Compliance with the study protocol was excellent. Further studies are needed to determine if patient-performed lung ultrasound can be useful to clinicians to detect and manage PVC in this patient population.

Assessment of Gas Production from Complex Hydrate System in Qiongdongnan Basin of South China Sea

The China Geological Survey (CGS) has carried out a large number of surveys and core drilling over the deepwater area of Qiongdongnan Basin (QDNB) in the South China Sea and discovered the natural gas hydrate system controlled by the gas chimney with a high geothermal gradient. The complex hydrate system consists of a sandy hydrate reservoir distributed around a lateral transition gas-hydrate mixed zone and a free gas zone in the middle. The hydrate and gas are distributed in the same layer, which is thin but potentially valuable for commercial exploitation. In this paper, a geological model of the target hydrate system in QDNB was established based on the results of several rounds of drilling. The method of numerical simulation was utilized to assess the production capacity of the target hydrate system and clarify the evolution of hydrate and gas saturation distribution with different well positions. The simulation results indicate that the producer well built in the center of the highly-saturated hydrate zone has a limited gas production capacity, with a cumulative production of only 7.25 × 106 m3 in 9 years. The well built at the boundary of the hydrate zone can rapidly link up the gas in the transition zone through a large production pressure differential, but it lacks control over the hydrates and its dissociated gas in the transition zone—the cumulative gas production volume from hydrate accounts for only 12.3%. As for the wells built in the transition zone and gas zone, they can directly invoke the free gas production capacity. Free gas is produced as the formation pressure reduces and hydrate is induced to dissociate, making the gas from the hydrate the subsequent production capacity. The cumulative production can exceed 6 × 108 m3 in 9 years. The stable production duration can extend to 2645 days, and the cumulative proportion of gas at the wellhead from hydrate reaches close to 30%. It is necessary to avoid the free water layer. The bottom water coning would improve the water production by 40% and shorten the stable production duration. In summary, the complex hydrate system of this type in the QDNB has the potential for industrialized exploitation. In the future, the well group can be used for the further improvement of the hydrate utilization rate.

Biowelding 3D-Printed Biodigital Brick of Seashell-Based Biocomposite by Pleurotus ostreatus Mycelium.

Mycelium biocomposites are eco-friendly, cheap, easy to produce, and have competitive mechanical properties. However, their integration in the built environment as durable and long-lasting materials is not solved yet. Similarly, biocomposites from recycled food waste such as seashells have been gaining increasing interest recently, thanks to their sustainable impact and richness in calcium carbonate and chitin. The current study tests the mycelium binding effect to bioweld a seashell biocomposite 3D-printed brick. The novelty of this study is the combination of mycelium and a non-agro-based substrate, which is seashells. As well as testing the binding capacity of mycelium in welding the lattice curvilinear form of the V3 linear Brick model (V3-LBM). Thus, the V3-LBM is 3D printed in three separate profiles, each composed of five layers of 1 mm/layer thickness, using seashell biocomposite by paste extrusion and testing it for biowelding with Pleurotus ostreatus mycelium to offer a sustainable, ecofriendly, biomineralized brick. The biowelding process investigated the penetration and binding capacity of the mycelium between every two 3D-printed profiles. A cellulose-based culture medium was used to catalyse the mycelium growth. The mycelium biowelding capacity was investigated by SEM microscopy and EDX chemical analysis of three samples from the side corner (S), middle (M), and lateral (L) zones of the biowelded brick. The results revealed that the best biowelding effect was recorded at the corner and lateral zones of the brick. The SEM images exhibited the penetration and the bridging effect achieved by the dense mycelium. The EDX revealed the high concentrations of carbon, oxygen, and calcium at all the analyzed points on the SEM images from all three samples. An inverted relationship between carbon and oxygen as well as sodium and potassium concentrations were also detected, implying the active metabolic interaction between the fungal hyphae and the seashell-based biocomposite. Finally, the results of the SEM-EDX analysis were applied to design favorable tessellation and staking methods for the V3-LBM from the seashell-mycelium composite to deliver enhanced biowelding effect along the Z axis and the XY axis with <1 mm tessellation and staking tolerance.

Morphologic, Atmospheric, and Oceanic Drivers Cause Multi‐Temporal Saltwater Intrusion on a Remote, Sand Island

AbstractSmall‐island populations disproportionately rely on fresh groundwater resources, which are increasingly threatened by salinization from changing ocean and climate conditions. This study investigates island groundwater dynamics and salinization over multiple timescales in response to marine, atmospheric, and morphologic drivers. New geophysical and hydrological data sets were collected on a remote sand island in the Northwest Atlantic Ocean between 2020 and 2022 and compared to historical baseline data from the 1970s. Data reveal saltwater intrusion due to multi‐decadal erosion, seasonal climate patterns, tidal forcing, and episodic flooding from Atlantic hurricanes. Long‐term dune erosion has caused the freshwater lens to thin and become asymmetrical; however, a lagged groundwater response causes the freshwater lens to be in disequilibrium with present island morphology. The maximum vertical lens thickness is seasonally constant, but the lateral transition zone along the coast thickens and moves seaward in spring when the water table is high from precipitation and frequent beach flooding. Groundwater level and electrical conductivity along low‐lying beaches significantly increase following Atlantic hurricanes due to seawater flooding, and reach a maximum of 1.93 m above sea level and 38 mS/cm, respectively. While groundwater levels recover quickly, conductivity (salinity) remains elevated due to the short intervals between winter flood events that outpace freshening from meteoric recharge. Results emphasize the importance of multi‐temporal groundwater dynamics and feedbacks between coastal flooding, erosion, and salinization. Field‐based studies considering multiple drivers and timescales of saltwater intrusion are critical for understanding and managing coastal freshwater resources in an age of rapid environmental change.

An MRI study of lateral vascular safety zones in oblique lumbar interbody fusion surgery

To study the anatomical characteristics of blood vessels in the lateral segment of the vertebral body through the surgical approach of oblique lumbar interbody fusion (OLIF) using MRI imaging, and evaluate its potential vascular safety zone. The lumbar MRI data of 107 patients with low back and leg pain who met the selection criteria between October 2019 and November 2022 were retrospectively analyzed. The vascular emanation angles, vascular travel angles, and the length of vessels in the lateral segments of the left vertebral body of L 1-L 5, as well as the distance between the segmental vessels in different Moro junctions of the vertebral body and their distances from the edges of the vertebrae in the same sequence (bottom marked as I, top as S) were measured. The gap between the large abdominal vessels and the lateral vessels of the vertebral body was set as the lateral vascular safe zones of the lumbar spine, and the extent of the safe zones (namely the area between the vessels) was measured. The anterior 1/3 of the lumbar intervertebral disc was taken as the simulated puncture center, and the area with a diameter of 22 mm around it as the simulated channel area. The proportion of vessels in the channel was further counted. In addition, the proportions of segmental vessels at L 5 without a clear travel and with an emanation angel less than 90° were calculated. Except for the differences in the vascular emanation angles between L 4 and L 5, the vascular travel angles between L 1, L 2 and L 4, L 5, and the length of vessels in the lateral segments of the vertebral body among L 1-L 4 were not significant ( P>0.05), the differences in the vascular emanation angles, vascular travel angles, and the length of vessels between the rest segments were all significant ( P<0.05). There was no significant difference in the distance between vessels of L 1, L 2 and L 2, L 3 at Moro Ⅰ-Ⅳ junctions ( P>0.05), in L 3, L 4 and L 4, L 5 at Ⅱ and Ⅲ junction ( P>0.05). There was no significant difference in the vascular distance of L 2, L 3 between Ⅱ, Ⅲ junction and Ⅲ, Ⅳ junction, and the vascular distance of L 3, L 4 between Ⅰ, Ⅱ junction and Ⅲ, Ⅳ junction ( P>0.05). The vascular distance of the other adjacent vertebral bodies was significant different between different Moro junctions ( P<0.05). Except that there was no significant difference in the distance between L 2I and L 3S at Ⅰ, Ⅱ junction, L 3I and L 4S at Ⅱ, Ⅲ junction, and L 2I and L 3S at Ⅲ, Ⅳ junction ( P>0.05), there was significant difference of the vascular distance between the bottom of one segment and the top of the next in the other segments ( P<0.05). Comparison between junctions: Except for the L 3S between Ⅰ, Ⅱ junction and Ⅱ, Ⅲ junction, and L 5S between Ⅰ, Ⅱ junction and Ⅱ, Ⅲ and Ⅲ, Ⅳ junctions had no significant difference ( P>0.05), there were significant differences in the distance between the other segmental vessels and the vertebral edge of the same sequence in different Moro junctions ( P<0.05). The overall proportion of vessels in the simulated channels was 40.19% (43/107), and the proportion of vessels in L 1 (41.12%, 44/107) and L 5 (18.69%, 20/107) was higher than that in the other segments. The proportion of vessels in the channel of Moro zone Ⅰ (46.73%, 50/107) and zone Ⅱ (32.71%, 35/107) was higher than that in the zone Ⅲ, while no segmental vessels in L 1 and L 2 were found in the channel of zone Ⅲ ( χ 2=74.950, P<0.001). Moreover, 26.17% (28/107) of the segmental vessels of lateral L 5 showed no movement, and 27.10% (29/107) vascular emanation angles of lateral L 5 were less than 90°. L 1 and L 5 segmental vessels are most likely to be injured in Moro zones Ⅰ and Ⅱ, and the placement of OLIF channels in L 4, 5 at Ⅲ, Ⅳ junction should be avoided. It is usually safe to place fixation pins at the vertebral body edge on the cephalic side of the intervertebral space, but it is safer to place them on the caudal side in L 1, 2 (Ⅰ, Ⅱ junction), L 3, 4 (Ⅲ, Ⅳ junction), and L 4, 5 (Ⅱ, Ⅲ, Ⅳ junctions).

Increased alpha-synuclein and neuroinflammation in the substantia nigra triggered by systemic inflammation are reversed by targeted inhibition of the receptor for advanced glycation end products (RAGE).

The receptor for advanced glycation end products (RAGE) is a protein of the immunoglobulin superfamily capable of regulating inflammation. Considering the role of this receptor in the initiation and establishment of neuroinflammation, and the limited understanding of the function of RAGE in the maintenance of this condition, this study describes the effects of RAGE inhibition in the brain, through an intranasal treatment with the antagonist FPS-ZM1, in an animal model of chronic neuroinflammation induced by acute intraperitoneal injection of lipopolysaccharide (LPS). Seventy days after LPS administration (2 mg/kg, i.p.), Wistar rats received, intranasally, 1.2 mg of FPS-ZM1 over 14 days. On days 88 and 89, the animals were submitted to the open-field test and were killed on day 90 after the intraperitoneal injection of LPS. Our results indicate that blockade of encephalic RAGE attenuates LPS-induced chronic neuroinflammation in different brain regions. Furthermore, we found that intranasal FPS-ZM1 administration reduced levels of gliosis markers, RAGE ligands, and α-synuclein in the substantia nigra pars compacta. Additionally, the treatment also reversed the increase in S100 calcium-binding protein B (RAGE ligand) in the cerebrospinal fluid and the cognitive-behavioral deficits promoted by LPS-less time spent in the central zone of the open-field arena (more time in the lateral zones), decreased total distance traveled, and increased number of freezing episodes. In summary, our study demonstrates the prominent role of RAGE in the maintenance of a chronic neuroinflammatory state triggered by a single episode of systemic inflammation and also points to possible future RAGE-based therapeutic approaches to treat conditions in which chronic neuroinflammation and increased α-synuclein levels could play a relevant role, such as in Parkinson's disease.

Application of towed TEM to geothermal areas of New Zealand

There is an increasing need to image the shallow (top 100 m) subsurface using geophysical techniques to inform resource use, resource protection, regulatory and policy development, community resilience, and, in general, how humans can live and interact with their environment. Geothermal systems are one such natural resource whose shallow hydrological structures are generally poorly understood, yet extensively utilised. Understanding the geothermal hydrology will inform potential environmental effects and the hydrothermal risk.The towed transient electromagnetic (tTEM) geophysical technique has been successfully applied to map permeability structures associated with current and/or historical near-surface geothermal flow and/or hydrothermal alteration in parts of the Rotorua and Wairakei-Tauhara Geothermal Fields, New Zealand. High-density tTEM measurements have enabled distinctive near-surface (top 100 m) resistivity anomalies to be identified and be interpreted. Large-scale resistivity anomalies that have been interpreted in this study include geothermal alteration associated with ascending boiling geothermal fluids, lateral near-surface permeable zones, and potential locations of aquifers that feed geothermal springs. Additional information is generally needed to differentiate between these potential causes of low resistivity anomalies.Contrasts in the modelled resistivities are stronger over “up-flow” areas (areas where near-boiling chloride-type water is rising close to the ground surface) compared to steam-heated geothermal areas. This is likely caused by vigorous processes (such as might be expected at the fluid-boiling interface) acting on the capping rock in the up-flow areas making the tTEM technique valuable in identifying potential fluid pathways from depth to the surface in these areas. New insights into the shallow permeability structure with possible near-surface boiling zones are located at 50 m below the ground at one of the study sites. Identification of these areas not only help understand how geothermal fluid moves from depth to the surface but can also contribute to managing the hydrothermal explosion hazard in these areas.

Self-adaptive turbulence eddy simulation of a premixed jet combustor

The self-adaptive turbulence eddy simulation (SATES) is employed to investigate the lean premixed methane/air turbulent flame in a single-nozzle model gas turbine combustor, in which the high axial momentum jet issuing from an off-center nozzle facilitates the development of a large-scale, dominant lateral recirculation zone that stabilizes the flame. For turbulence modeling, the SATES method can dynamically adjust the proportion of resolving and modeling of turbulent scales according to the local grid scale and turbulence length scales, thus depressing the gird-sensitivity in large eddy simulation (LES) calculation. For combustion modeling, the thickened flame model with a reduced chemistry mechanism is integrated into the SATES turbulence modeling framework to capture the unsteady flame dynamics. The accuracy of SATES results is assessed against experimental data, as well as the ones from LES and the detached eddy simulation (DES) of this burner with the same combustion model and grids. The predicted length of large-scale recirculation of the flow field by SATES is significantly better than that by LES and DES with low mesh resolution. Detailed comparisons show that the SATES adaptively improves the modeling degree of near-wall turbulence to improve the prediction accuracy with the low grid resolution. Similar to LES, the SATES method does not cause serious delay of shear layer instability and weakening of flame wrinkle observed in DES. The study demonstrates the suitability and accuracy of the hybrid turbulence modeling methods of SATES for complex turbulent flame simulations coupled with suitable combustion model.

Portal Selection for Suture Anchor Placement During Hip Arthroscopic Labral Repair: A Study Based on 3-Dimensional Model Reconstruction.

Arthroscopic suture repair is the main treatment option for hip labral tears; however, anchor insertion and placement from arthroscopic portals is difficult. To quantitatively evaluate the safety of various arthroscopic portals for suture anchor placement during hip labral repair. Descriptive laboratory study. The computed tomography scans of 20 patients with normally developed hip joints were used to create 3-dimensional models. The distances from the anchor to the articular cartilage (DAC) and from the acetabular insertion point to the cortical bone (DCB) were measured in the anterolateral portal (AL), posterolateral portal (PL), midanterior portal (MAP), medial MAP, and 3 distal anterolateral accessory portals (DALAs): DALA-proximal, DALA-middle, and DALA-distal. Labral tears were divided into anterior (4, 3, and 2 o'clock), lateral (1, 12, and 11 o'clock), and posterior (10, 9, and 8 o'clock) acetabular zones, and the Kruskal-Wallis and Mann-Whitney U test were used to compare DAC and DCB in the zones. The success rate was defined as anchors placed with DAC ≥1 mm and DCB ≥15 mm. The DAC was significantly smaller in the AL at 1 o'clock (0.68 ± 0.32 mm; P < .001) and 12 o'clock (0.37 ± 0.30 mm; P < .001), and in the PL at 12 o'clock (-0.35 ± 0.38 mm; P < .001) and 11 o'clock (0.60 ± 0.24 mm; P < .001). The DCB was significantly smaller in the DALA-P at 3 o'clock (8.93 ± 2.12 mm; P < .001) and 11 o'clock (9.59 ± 2.84 mm; P < .001), the MAP at 12 o'clock (13.76 ± 3.89 mm; P < .001) and 11 o'clock (0.27 ± 0.27 mm; P < .001), and the MMA at 12 o'clock (5.96 ± 2.31 mm; P < .001) and 11 o'clock (0 mm; P < .001). Success rates were high for MAP and MMA between 4 o'clock and 1 o'clock, for DALA-proximal at 12 o'clock, for AL at 11 o'clock, and for PL between 10 o'clock and 8-o'clock. There were significant differences in the success rate of anchor placement using different portals during hip arthroscopic labral repair. MAP is recommended for labral repair between 4 o'clock and 1 o'clock, DALA-P is recommended between 2 o'clock and 12 o'clock, AL is suitable at 11 o'clock, and PL is suitable between 10 o'clock and 8 o'clock.

Scaling thermal and mechanical characteristics of woven honeycombs: A novel endeavor of simultaneous ridges and picking sequence variation

This study provides structural versatility to textile fabrics, honeycombs woven structures, for tuning their thermal and mechanical properties. Six different honeycomb structures, single ridge, double ridge, and brighton honeycomb with two different picking sequences were engineered their thermal and mechanical characterizations i.e., dry fluids transmission, wet fluids management capabilities, heat retention properties, tensile strength, and puncture resistance, were evaluated. Increasing the number of axial and lateral yarn interlacement zones compromised dry fluid mobility, and heat retention capability by increasing material bulk and also the increase in bulk worked for about 15% enhancement in wet fluids management. Changing the picking sequence, from single pick to double pick, improved wet fluid management up to 20%. Honeycomb structures with higher interlacement and areal densities showed higher tensile properties and puncture resistance. The relevance of the analyzed experimental variables was also visualized using statistical analysis, with p-values less than 0.05 being considered significant.

Poster 256: Pediatric Meniscus Repair: Safety Profile based on &gt; 2000 Arthroscopic Meniscus Repairs

Objectives: Pediatric meniscus tear prevalence is increasing, and meniscus preservation methods are essential for long term knee function in this at risk group. In this patient population meniscus anatomy and vascularity may support higher rates of healing after repair, but safety of meniscus repair has not been studied in a large prospective cohort group. The purpose of this study is to establish the incidence of complications associated with pediatric meniscus repairs in a multi-center prospective quality improvement registry, and to identify the characteristics of meniscus repair that are associated with complications. Methods: A prospective multi-center quality improvement registry (16 institutions, 26 surgeons) monitoring the safety of meniscus repairs was reviewed. Audit processes using CPT codes were designed to ensure that all consecutive cases were prospectively entered on patients &lt;19 years old into a HIPAA- compliant electronic platform. Each meniscus repair case with a complication form was secondarily reviewed to ensure consistency of identification and grading according to the modified Clavien Dindo classification. Demographics, tear type, repair technique, and implant type, when applicable, were included, and a common cause analysis was performed to evaluate risk factors for early repair failures. Results: 2375 meniscus repair cases were identified, with a mean age of 15.1 years (2-19) and 44.1% females. These consisted of (25%) isolated repair, (5.4%) discoid meniscus repair, and (66.9%) concomitant ACL and meniscus repair. Overall complication rate was 12.64%, with 5.67% grade III complications. The most common complications were motion loss/stiffness (3.96%), failed repair (2.3%) and continued pain/mechanical symptoms (2.09%). Failed repair was identified in all repair groups but had the highest prevalence in isolated meniscus repair (6.38%), in which grade III complications were more common overall. Stiffness was more common when a meniscus repair was performed during an ACL reconstruction (2.1% Grade II and 1.27% Grade III). There was no statistical difference in complications associated with age, gender, or technique, medial or lateral meniscus, displacement, or zone of repair. However, posterior horn and posterior horn + body repairs of the medial meniscus sustained more complications (p=0.003) as did longitudinal/complex tears of the lateral meniscus (p=0.02). Conclusions: Pediatric meniscus repairs performed arthroscopically have a complication rate of 12.64%, with 1 and 20 meniscus repairs leading to a grade III complication. Although there is no difference in complications based on technique, posterior horn medial meniscus and longitudinal tears of lateral meniscus may be at higher risk of complications.

Paper 45: Which Osteochondritis Dissecans Subjects Will Heal Non-Operatively? An Application of Machine Learning Methods to the ROCK Cohort

Paper 45: Which Osteochondritis Dissecans Subjects Will Heal Non-Operatively? An Application of Machine Learning Methods to the ROCK Cohort

Cortical regulation of neurogenesis and cell proliferation in the ventral subventricular zone

Neurogenesis and differentiation of neural stem cells (NSCs) are controlled by cell-intrinsic molecular pathways that interact with extrinsic signaling cues. In this study, we identify a circuit that regulates neurogenesis and cell proliferation in the lateral ventricle-subventricular zone (LV-SVZ). Our results demonstrate that direct glutamatergic projections from the anterior cingulate cortex (ACC), as well as inhibitory projections from calretinin+ local interneurons, modulate the activity of cholinergic neurons in the subependymal zone (subep-ChAT+). Furthermore, invivo optogenetic stimulation and inhibition of the ACC-subep-ChAT+ circuit are sufficient to control neurogenesis in the ventral SVZ. Both subep-ChAT+ and local calretinin+ neurons play critical roles in regulating ventral SVZ neurogenesis and LV-SVZ cell proliferation.