Entry Location Research Articles

Study on the rockburst risk of alternate exterior entry under island coal pillar

The extraction of extremely thick coal seams through slicing mining requires leaving behind several island coal pillars in the top slicing, which could lead to rockburst in the bottom slicing. This article proposed a method of alternate exterior entry (AEE) for rockburst prevention based on the stress distribution of bottom slicing. The influences of coal pillar width [Formula: see text] and stress concentration factor [Formula: see text] on stress distribution were explored using two-dimensional stress imaging. The results indicated that K value had a greater effect on stress distribution comparing with B value. Both stress relaxed and stress rate angles increased linearly with an increase in K value. In order to get the optimized location of AEE in the coal mine stress rate angle was chosen as the stress extension angle, which was further verified by field data from 1210 coal faces. Finally, numerical simulation was used to explore the optimized location of special tail entry under dip island coal pillars for rockburst prevention. It was revealed that plan first was found to be most effective due to its presence in a stress-relaxed area, thus verifying the effectiveness of the AEE method for rockburst prevention.

Microplastic pollution in the surface water of Yele Mallappa Shetty Lake, Bengaluru: first report

Aim: This study was conducted to identify and characterize microplastics in Yele Mallappa Shetty (YMS) Lake, Bengaluru. Methodology: Water samples were collected from four distinct entry locations to the lake and analysed for microplastic as per the methods adopted by the National Oceanic and Atmospheric Administration (NOAA). Results: Samples of three different microplastic foams—polyester, polyurethane, and polypropylene—were analysed using scanning electron microscopy (SEM), visual analysis, hot needle testing and Raman spectroscopy. The diameters of various components ranged from 0.2-3 mm, with the majority of the samples consisting of fibres (26%), fragments (27%), films (25%) and foam (22%). The mean concentration of microplastic recorded in the water sample was 10±0.7 particles l-1. Interpretation: Protecting wetland ecosystems is essential because they provide countless services, such as food and building materials, biodiversity, flood control, and groundwater recharge. This study provideds valuable baseline data on microplastics in YMS lake for the first time. Key words: Bengaluru lake; Lake water, Microplastic pollution, Water pollution, Yele Mallappa Shetty Lake

Multilevel approximation of Gaussian random fields: Covariance compression, estimation, and spatial prediction

The distribution of centered Gaussian random fields (GRFs) indexed by compacta such as smooth, bounded Euclidean domains or smooth, compact and orientable manifolds is determined by their covariance operators. We consider centered GRFs given as variational solutions to coloring operator equations driven by spatial white noise, with an elliptic self-adjoint pseudodifferential coloring operator from the Hörmander class. This includes the Matérn class of GRFs as a special case. Using biorthogonal multiresolution analyses on the manifold, we prove that the precision and covariance operators, respectively, may be identified with bi-infinite matrices and finite sections may be diagonally preconditioned rendering the condition number independent of the dimension p of this section. We prove that a tapering strategy by thresholding applied on finite sections of the bi-infinite precision and covariance matrices results in optimally numerically sparse approximations. That is, asymptotically only linearly many nonzero matrix entries are sufficient to approximate the original section of the bi-infinite covariance or precision matrix using this tapering strategy to arbitrary precision. The locations of these nonzero matrix entries can be determined a priori. The tapered covariance or precision matrices may also be optimally diagonally preconditioned. Analysis of the relative size of the entries of the tapered covariance matrices motivates novel, multilevel Monte Carlo (MLMC) oracles for covariance estimation, in sample complexity that scales log-linearly with respect to the number p of parameters. In addition, we propose and analyze novel compressive algorithms for simulating and kriging of GRFs. The complexity (work and memory vs. accuracy) of these three algorithms scales near-optimally in terms of the number of parameters p of the sample-wise approximation of the GRF in Sobolev scales.

19F-NMR Probing of Ion-Induced Conformational Changes in Detergent-Solubilized and Nanodisc-Reconstituted NCX_Mj.

Consecutive interactions of 3Na+ or 1Ca2+ with the Na+/Ca2+ exchanger (NCX) result in an alternative exposure (access) of the cytosolic and extracellular vestibules to opposite sides of the membrane, where ion-induced transitions between the outward-facing (OF) and inward-facing (IF) conformational states drive a transport cycle. Here, we investigate sub-state populations of apo and ion-bound species in the OF and IF states by analyzing detergent-solubilized and nanodisc-reconstituted preparations of NCX_Mj with 19F-NMR. The 19F probe was covalently attached to the cysteine residues at entry locations of the cytosolic and extracellular vestibules. Multiple sub-states of apo and ion-bound species were observed in nanodisc-reconstituted (but not in detergent-solubilized) NCX_Mj, meaning that the lipid-membrane environment preconditions multiple sub-state populations toward the OF/IF swapping. Most importantly, ion-induced sub-state redistributions occur within each major (OF or IF) state, where sub-state interconversions may precondition the OF/IF swapping. In contrast with large changes in population redistributions, the sum of sub-state populations within each inherent state (OF or IF) remains nearly unchanged upon ion addition. The present findings allow the further elucidation of structure-dynamic modules underlying ion-induced conformational changes that determine a functional asymmetry of ion access/translocation at opposite sides of the membrane and ion transport rates concurring physiological demands.

The timing and location of entry in growing markets: subgame perfection at work

AbstractWe develop and analyze a dynamic model in which firms decide when and where to enter a growing market. We do not pre‐specify the order of entry, allowing instead for the leader and follower to be determined endogenously. We characterize the subgame perfect equilibria of the dynamic game and show the times and locations of entry are governed by the threat of preemption, which leads to premature entry, less extreme locations, and the dissipation of rents. Using data on gas stations, restaurants, and hotels in isolated markets, we find results consistent with subgame perfection for gas stations and three‐star hotels.

Maze-solving in a plasma system based on functional analogies to reinforcement-learning model.

Maze-solving is a classical mathematical task, and is recently analogously achieved using various eccentric media and devices, such as living tissues, chemotaxis, and memristors. Plasma generated in a labyrinth of narrow channels can also play a role as a route finder to the exit. In this study, we experimentally observe the function of maze-route findings in a plasma system based on a mixed discharge scheme of direct-current (DC) volume mode and alternative-current (AC) surface dielectric-barrier discharge, and computationally generalize this function in a reinforcement-learning model. In our plasma system, we install two electrodes at the entry and the exit in a square lattice configuration of narrow channels whose cross section is 1×1 mm2 with the total length around ten centimeters. Visible emissions in low-pressure Ar gas are observed after plasma ignition, and the plasma starting from a given entry location reaches the exit as the discharge voltage increases, whose route converging level is quantified by Shannon entropy. A similar short-path route is reproduced in a reinforcement-learning model in which electric potentials through the discharge voltage is replaced by rewards with positive and negative sign or polarity. The model is not rigorous numerical representation of plasma simulation, but it shares common points with the experiments along with a rough sketch of underlying processes (charges in experiments and rewards in modelling). This finding indicates that a plasma-channel network works in an analog computing function similar to a reinforcement-learning algorithm slightly modified in this study.

Sources and paths of extreme cold surges over China and their associated atmospheric circulations

AbstractThe extreme cold surges (ECSs) are among the extreme weather events that affect China. Here, a total of 31 ECSs that occurred from 1962 to 2018 in China were identified using observed temperature data. In addition, we used the hybrid single‐particle Lagrangian integrated trajectory (HYSPLIT) model to trace their sources. And the atmospheric circulation of ECSs with different paths were investigated. The ECSs were classified to K‐type, B‐type and S‐type ECSs (which was subdivided into the S1‐type, S2‐type and S3‐type) according to their origins and entry locations into China. The S‐type ECSs occurred the most, accounting for 58.06%. The duration and temperature drop of the K‐type ECSs were higher than those of others. And K‐type and S1‐type ECSs mainly affected Northeast China, S2‐type ECSs mainly affected the regions east of 105° E. For decadal variation, Since the 1980s, ECSs frequency has decreased (especially only one ECS occurred in the 1980s), and K‐type and S2‐type ECSs disappeared. Different types of cold surges have different atmospheric circulation characteristics. The “positive–negative–positive” wave train structures of geopotential height anomalies at 500 hPa were very conducive to the formations of K‐type, B‐type and S3‐type ECSs. For K‐type and S1‐type ECSs, the cold high gradually moved south to Siberia, and combined with the cyclone anomalies, causing the cold air to enter China. Before the B‐type ECSs occurred, cold high appeared in the west of Xinjiang, which made the southeast cold air invade China. Regarding S1‐type and S2‐type ECSs, the negative anomalies over Eurasia from day −6 to day −4 and the subsequent cyclone anomalies at 850 hPa accompanied by the southeastward extension of cold high led to ECSs.

Heat Transfer and Pressure Drop in Plate Fin Heat Exchangers: A Numerical Approach

An apparatus for transferring thermal energy across an impermeable barrier between two or more fluids is a heat exchanger. The effective transmission of heat from a hot fluid to a cold fluid is its primary goal. The temperature differential between the two fluids directly affects this heat transfer. Using CFD study with FLUENT 2020 R1, the performance characteristics of the compact plate fin heat exchanger's improved surfaces are examined. The simulation of heat transfer and flow encompassed a variety of velocities including completely turbulent regions. The pressure, temperature, and velocity contours were taken from the Fluent simulations. To determine the heat exchanger's flow and heat transfer performance, numerical analysis has been done. Since boundary conditions are crucial to CFD, they have been carefully chosen. The flow field, heat transfer, thickness, and wavelength were all predicted using the software code for a range of air to water velocities. Three distinct wavelengths of numerical simulations for a plate-fin heat exchanger were used in the study (10, 20, and 30). There were changes to the fin thickness, entry locations, and air and water entry velocities. Solid Works and Ansys were used to create the geometry for the three-level fin models that were placed inside the heat exchanger, both with and without a cover. For determining the heat exchanger's geometry and fin isometry, three levels measuring 19.6 mm in height and 53.64 mm in width were constructed. The fins have a thickness of 0.2 to 0.4 mm. As the air and water velocities vary, so does the temperature inside the heat exchanger. Because the topmost layer is a warm stream's flow channel, the temperature rises there, whereas the opposite effect is seen close to the bottom layer. Convection heat transmission to the surroundings and conduction heat transfer through the heat exchanger's side plates are the causes of fluid temperature fluctuations in the depth direction.

UNDERSTANDING THE RELATIONSHIP BETWEEN AIR QUALITY AND FIVE-YEAR SURVIVAL OF PATIENTS IN THE AMERICAN FAMILY COHORT

Abstract Air pollution is an important social determinant of health and associated with cardiopulmonary disease, cancer, diabetes, and cognitive impairment. This study examined the impact of air pollution on the mortality of patients in the American Family Cohort (AFC), a national dataset of 6.6 million Americans, derived from the American Board of Family Medicine PRIME Registry electronic health record data. The AFC data were merged with the Environmental Protection Agency’s Air Quality Index (AQI) measures for the study period (2016-2022). Two Cox-Regression-Models were performed to determine how (1) baseline air quality and (2) air quality measures over time would affect patients’ five-year survival. Fixed covariates of interest--gender, race, age, location, and year of entry into the study--were studied as well. The adjusted hazard of death in the group with baseline AQI greater than 50 was 4.02 times higher than that of the group with AQI less than or equal to 50 (95% CI: 3.36, 4.82, p < 0.05). Compared to younger patients, the hazard of death was 6.73 times higher in persons older than 80 years of age (95% CI: 5.47, 8.28; p < 0.05). Black/African American patients had a 4.27 times higher hazard of death (95%CI: 3.47, 5.26; p < 0.05) compared to other races. Our study shows that vulnerable populations (older adults and persons from minority communities) are disproportionately burdened by poor air quality. Public health initiatives that focus on improving air quality for minority communities will improve their longevity.

Oil-Water Flowing Experiments and Water-Cut Range Classification Approach Using Distributed Acoustic Sensing

Summary The accurate measurement of dynamic water cut is of great interest for analyzing reservoir performance and optimizing oilwell production. Downhole water-cut measurement is a very challenging work. Moreover, the surface-measured water cut is a comprehensive indicator of commingled producing well and it is difficult to use this parameter to deduce the downhole water cut of each contributing layer. In this paper, we propose to use distributed fiber-optic acoustic sensing (DAS) technology for the classification of water-cut range. DAS can dynamically monitor the entire wellbore by “listening” to the acoustic signals during flow. A large number of laboratory experimental data from DAS have been collected and analyzed using wavelet time scattering transform and short-time Fourier transform (STFT). The extracted low-variance scattering feature, short time-frequency feature, and fusion feature (combination of two extracted features) were learned with backpropagation (BP) neural network, decision tree (DT), and random forest (RF) algorithm. Then, a classification method of water-cut range in oil-water flow was established with machine learning. Field DAS data were collected from two oil wells to verify the effectiveness of the proposed method. The classification accuracies for the vertical well (Well A) are 92.4% and 87.4% by DT and RF model, respectively. For the horizontal well (Well B), the average classification accuracy exceeds 90% for all three methods. Water shutoff measure was conducted in Well B, and an obvious water decrease was realized. The result shows that the fusion feature overweighs single feature in machine learning with DAS data. This study provides a novel way to identify downhole water-cut range and detect water entry location in horizontal, vertical, and deviated oil-producing wells.

Infrared spectroscopy as a tool for hydrothermal alteration mineral analysis to support geothermal reservoir characterization at The Geysers, California, USA

Infrared reflectance spectroscopy (IRS), an analytical method for characterizing geologic materials, is becoming more commonly applied to geothermal energy applications. However, few case studies are available in the literature and are restricted to relatively few volcanic/geologic environments. We present an interpretation of reservoir mineralogy using IRS on drill cuttings from an active magmatic-heat-sourced geothermal system hosted in metamorphic rocks known as “The Geysers”, located in northern California and operated by Calpine Corp. Wavelength ranges investigated include the Short Wave Infrared (SWIR; 1000–2500 nm) and the Long Wave Infrared (LWIR; 2.5–20 μm). We apply this technique to a 2848 m-deep geothermal production well in the northwest Geysers, inferred to overlie a Holocene intrusion and zone of partial melt as indicated by geophysics. We utilized this non-destructive technique to analyze every drill-cuttings sample (3000+ measurements collected at ∼3.3 m intervals). We identify a zonation in mineralogy that changes from illite + chlorite ± kaolinite ± smectite ± calcite at shallow depths (0–1000 m), to illite + chlorite ± calcite at intermediate depths (1000–2200 m), to actinolite + biotite + chlorite ± tourmaline at greatest depths (2200–2848 m). We find the change at 2200 m is proximal to the inferred transition from the “normal” temperature reservoir (∼240 °C vapor-dominated convective zone) to the high temperature reservoir (up to 400 °C, conduction-dominated). We identify a possible association between 1900 nm H2O absorptions and current steam entry locations. The results of the SWIR and LWIR analysis are consistent with some caveats with newly collected bulk rock X-Ray Diffraction (XRD) data, and support and compliment previous work at the Geysers utilizing XRD and petrographic analysis.

Prevalence and Characterization of External Cervical Resorption Using Cone Beam Computed Tomography

IntroductionThe aim of this study was to assess the prevalence of external cervical resorption (ECR) and characterize the cases of ECR using cone beam computed tomography (CBCT). MethodsHigh-resolution CBCT scans of 6216 patients (2280 males and 3936 females), consecutively acquired during the period July 2021 to March 2022, were analyzed. Identified cases of ECR were characterized by 3 evaluators regarding lesion height, circumferential spread, portal of entry proximity to root canal, stage, location, and width. ResultsIn a total of 38 patients and 40 teeth, ECR cases demonstrated an incidence of 0.61%. The median age of the patients was 39 years. Prevalence of ERC was 0.78% among males and 0.50% among females. The most affected teeth were the maxillary incisors and canines. The most frequent characteristics of the lesion were: extension up to the cervical third (47.5%), more than 270° circumferential spread (42.55%), probable pulpal involvement (57.5%), progressive stage (65%), supracrestal (52.1%) and mesial (34.7%) localization of >1 mm in size (52.1%) portals of entry. Cases with greater longitudinal involvement also showed greater circumferential progression (P = .008). There was no association between portal of entry location and bone crest or ECR reparative phase (P = .42). Inter-rater agreement ranged from good to very good. No association between portal of entry and ECR progression was observed. ConclusionsECR showed low prevalence in the Brazilian population, affecting mostly anterior maxillary teeth of patients within a wide age range. CBCT allowed characterization of ECR lesions with good interobserver agreement.

Fresh Water and Atmospheric Cooling Control on Density-Compensated Overturning in the Labrador Sea

Abstract As they rim the basin from the southern tip of Greenland to the southern Labrador coast, the waters in the Labrador Sea boundary current undergo a significant transformation in salinity and temperature, but much less so in density. Motivated by these observations, a previously developed simple three-layer model is adapted to understand the processes responsible for this density-compensated overturning in the Labrador Sea. From our model simulations, we find that the density-compensating water mass transformation in the boundary current can be largely attributed to the combined effect of 1) direct atmospheric cooling of the relatively warm boundary current and 2) freshening due to mixing with the shallower and fresh waters derived from Greenland meltwater discharge and Arctic Ocean inflow. Freshening of the boundary current waters due to the excess of precipitation over evaporation in the basin has an important, but less impactful, role in the density compensation. Studies examining the sensitivity of the density compensation to the freshwater entry location reveal a larger impact when the freshwater enters the boundary current on the Greenland side of the basin, compared to the Labrador side. These results yield insights into how increasing meltwater in the subpolar North Atlantic will affect the overturning.

Tetanus patient profiles and factors affecting clinical outcomes at Dr. Soedono general hospital, Madiun in 2019-2020

Link of Video Abstract: https://youtu.be/VC3Gcd7oS5Y Introduction: Tetanus is a disease that can be diagnosed clinically. However, there is a lack of research data on tetanus patients and their clinical outcomes, especially in adult tetanus patients in Indonesia. This study aims to determine the factors that influence the outcome of tetanus patients. Method: A cross-sectional study was performed from May to June 2021 at Dr. Soedono Madiun General Hospital. Subjects were recruited by total sampling. The data that will be taken in this study are gender, age, immunization history, incubation period, onset, port of entry, Philips score, and clinical outcomes of patients. Result: Were 112 patients diagnosed with tetanus at Dr. Soedono General Hospital from January 2019 to December 2020. The male subjects outnumbered female subjects by 81.3%. The youngest subject was 19 years old, and the oldest was 81 years old. The tetanus immunization status showed that 2 patients were known to be fully immunized, 21 were not fully immunized, and 89 (79.5%) had unknown immunization status. This study showed that the port of entry of the wound is most often the entry point for tetanus in the inferior extremity of 72 patients (64.3%). Most onset occurred in 1-7 days, with a mean onset for generalized tetanus was 2.3 ± 1.8 days. The mean incubation period for the appearance of tetanus symptoms in this study was 9.4 ± 5.6 days. The most common comorbid disease in this study was diabetes mellitus (11.6%). This study's clinical outcome of tetanus showed that 74 patients (66.1%) had improved, while 38 patients (33.9%) died during treatment. Discussion: This study's most common port of entry was on the inferior extremities. This lower limb predominance as the port of entry could be explained by the fact that C. tetani exists in soil; hence, any lower limb injury would be open to contamination and infection by this organism. Based on the Dakar and Phillips score system, tetanus has a worse prognosis when there is a faster incubation period, faster onset, more proximal port of entry location, immunization status, comorbidities and signs of muscle spasm, fever, and tachycardia are obtained. Conclusion: In this study, tetanus still has a high mortality rate. Male gender, age over 45, a moderate to severe disease degree (considering a relatively short incubation time, short onset period, and unknown immunization status) are a few factors that may affect this high mortality rate.

Clinical characteristics and therapeutic strategy for patients with spontaneous isolated abdominal aortic dissection.

Spontaneous isolated abdominal aortic dissection (SIAAD) is a rare aortic emergency and not yet fully understood. This study aims to report the characteristics and treatments of 31 patients with SIAAD in the past 12 years. A total of 31 consecutive patients with SIAAD between 2010 and 2022 were included. The clinical manifestations, treatment strategies, and outcomes were reviewed. Following the SVS/STS reporting standard, we compared the clinical characteristics with different locations of primary entry, or different numbers of dissected zones. Furthermore, we compared the effects of surgical and conservative therapies on the outcome during the follow-up. Among the 31 patients with SIAAD, 16 (51.6%) were in the acute phase on admission. The primary entry of SIAAD was mainly located in Zone 9 (67.7%). Most patient presented with dissection involving 1 or 2 aortic zones (61.3%). In addition, 35.5% and 64.5% of SIAADs involved the visceral and iliac arteries, respectively. Compared with asymptomatic SIAADs, the symptomatic ones had longer dissection lengths (P = 0.008) and tended to involve iliac artery more frequently (P = 0.098). There were differences in the number of dissected aortic zones (P = 0.005) among patients with primary entry located in Zone 5 (Supraceliac aorta), Zone 6-8 (Paravisceral aorta) and Zone 9 (Infrarenal aorta). The involvement of visceral artery (P = 0.039) and iliac artery (P = 0.006) was significantly different between the subgroups of SIAAD involving one, two, and three or more aortic zones. The cumulative incidence of adverse false lumen progression events was significantly lower (P = 0.000) and the rate of false lumen thrombogenesis or disappearance was higher in patients receiving surgery (P = 0.001). The cumulative all-cause mortality was 9.7% at 1-year, and 19.7% at 5-year, with no significant difference between surgical and conservative therapies. Clinical features of SIAAD vary depending on the location of the primary entry and the number of dissected aortic zones. Although surgery was not associated with a lower all-cause mortality compared with conservative therapy, it was associated with a lower incidence of adverse false lumen progression and a higher rate of aortic remodeling.

Stepwise osteotomy protocol for zygomatic implant placement under navigation in patients with extra-sinus trajectory

This technical note describes a stepwise osteotomy for zygomatic implant placement with an extra-sinus trajectory under navigation using virtual markers for registration. The stepwise osteotomy protocol divides the trajectory of the zygomatic implant osteotomy into three consecutive co-axial components. The aim is to achieve better control of the osteotomy under navigation and to minimize or eliminate any intermittent free-hand drilling. The stepwise osteotomy protocol facilitates the use of shorter drills to finish the zygomatic implant osteotomy at the entry location before switching back to the long drill to complete the whole osteotomy. This protocol has been applied in a patient and the preliminary result is promising. However, the clinical effectiveness of this approach requires further investigation in prospective clinical studies.

Atmospheric pressure plasma treatment of skin: penetration into hair follicles

Sterilization of skin prior to surgery is challenged by the reservoir of bacteria that resides in hair follicles. Atmospheric pressure plasma jets (APPJs) have been proposed as a method to treat and deactivate these bacteria as atmospheric plasmas are able to penetrate into structures and crevices with dimensions similar to those found in hair follicles. In this paper, we discuss results from a computational investigation of an APPJ sustained in helium flowing into ambient air, and incident onto a layered dielectric similar to human skin in which there are idealized hair follicles. We found that, depending on the location of the follicle, the bulk ionization wave (IW) incident onto the skin, or the surface IW on the skin, are able to launch IWs into the follicle. The uniformity of treatment of the follicle depends on the location of the first entry of the plasma into the follicle on the top of the skin. Typically, only one side of the follicle is treated on for a given plasma pulse, with uniform treatment resulting from rastering the plasma jet across the follicle over many pulses. Plasma treatment of the follicle is sensitive to the angle of the follicle with respect to the skin, width of the follicle pocket, conductivity of the dermis and thickness of the underlying subcutaneous fat layer, the latter due to the change in capacitance of the tissue.

Freehand vs. Medial Portal Offset Aimer Technique for Accurate Femoral Tunnel Placement in Arthroscopic ACL Reconstruction.

In this study, our aim was to reveal the effect of the medial femoral offset aimer usage through the femoral tunnel entry and exit points and the tunnel length during femoral tunnel drilling in arthroscopic anterior cruciate ligament (ACL) reconstruction. One hundred patients who underwent arthroscopic single-bundle ACL reconstruction were included in the study. Group 1 consisted of 50 patients who underwent femoral tunnel drilling using a medial portal offset aimer device, while Group 2 consisted of 50 patients who were operated on using the freehand technique. Both groups were compared in terms of femoral tunnel and graft tunnel lengths, femoral tunnel angle in the coronal plane, and the location of the femoral tunnel entry and exit points. The mean femoral tunnel and graft tunnel lengths were significantly longer in Group 2 (p = 0.000). There was no significant difference in terms of localization of the femoral tunnel entry point in both the axial and sagittal planes. The tunnel exit point was located significantly more posterior in Group 1 in the axial plane (p = 0.028). There was no significant difference in terms of the coronal plane femoral tunnel angle between the two groups. In arthroscopic ACL reconstructions, more successful results may be obtained with the freehand technique compared to drilling with a femoral offset aimer. For an experienced orthopedic surgeon, using a medial portal offset aimer device during femoral tunnel drilling does not seem necessary. The online version contains supplementary material available at 10.1007/s43465-023-00929-z.

A three-dimensional perspective of phosphorus retention across a field-buffer strip transition

Vegetated filter strips (VFS) act as buffer zones between fields and water bodies that are supposed to retain incoming runoff, sediment, and nutrients. The factors that govern nutrient retention and cycling in VFS are complex and act in all three dimensions. A key element that determines VFS effectivity is flow type, e.g., sheet vs. concentrated flow. These aspects are, however, often insufficiently accounted for in VFS research and design recommendations. In this study, we attempt to tackle these shortcomings by examining the nutrient distribution in detail at two field-VFS transitions, applying a three-dimensional sampling array together with extensive laboratory analyses. Concentrated runoff was the dominant type we found and we argue that flow convergence is the norm rather than the exception. Further complicating this issue is that entry locations of runoff may vary, calling for more sophisticated sampling designs. Overall trends were similar across the analyzed nutrient fractions (different K- and P-pools) and there were distinct trends of decreasing nutrients along the longitudinal (from the field to the VFS) and vertical planes. The horizontal plane (from outside to inside the area of concentrated flow) showed mostly inconclusive or U-shaped gradients. Both sites were similar and close to each other, nevertheless, there were significant differences that affected nutrient retention in the VFS which were linked to site-specific factors. The spatial extent (i.e., width) is often considered the main variable in VFS designs. However, other VFS traits such as vegetation type and structure, as well as external factors such as field topography and the severity of erosive events are equally important and should be attributed more significance.

Anatomical analysis of the motor endplate zones of the suprascapular nerve to the infraspinatus muscle and its clinical significance in managing pain disorder.

Myofascial pain syndrome caused by myofascial trigger points is a musculoskeletal disorder commonly encountered in clinical practice. The infraspinatus muscle is the region most frequently involved in the myofascial pain syndrome in the scapular region. The characteristics of the myofascial trigger points are that they can be found constantly in the motor endplate zone. However, localizing myofascial trigger points within the motor endplate zone and establishing an accurate injection site of the infraspinatus muscle has been challenging because the anatomical position of the motor endplate zone of the infraspinatus muscle is yet to be described. Therefore, this cadaveric study aimed to scrutinize the motor endplate zone of the infraspinatus muscle, propose potential myofascial trigger points within the muscle, and recommend therapeutic injection sites. Twenty specimens of the infraspinatus muscle for nerve staining and 10 fresh frozen cadavers for evaluation of the injection were used in this study. The number of nerve branches penetrating the infraspinatus muscle and their entry locations were analyzed and photographed. Modified Sihler's staining was performed to examine the motor endplate regions of the infraspinatus muscle. The nerve entry points were mostly observed in the center of the muscle belly. The motor endplate was distributed equally throughout the infraspinatus muscle, but the motor endplate zone was primarily identified in the B area, which is approximately 20-40% proximal to the infraspinatus muscle. The second-most common occurrence of the motor endplate zone was observed in the center of the muscle. These detailed anatomical data would be very helpful in predicting potential pain sites and establishing safe and effective injection treatment using botulinum neurotoxin, steroids, or lidocaine to alleviate the pain disorder of the infraspinatus muscle.