Lower Position Research Articles

Surgical Correction of Low-positioned Umbilicus after Mini-abdominoplasty.

The umbilicus detachment and reinsertion in umbilical float mini-abdominoplasty results in its lower position with or without shape distortion. This event creates a stigmatizing look, elongating the upper abdomen and creating variable grades of infra umbilical/pubis bulging. This lack of proportion causes an unpleasant, artificial look, and is very difficult to fix. The study aimed to describe a sequence of abdominoplasty and combined upper abdomen horizontal muscle plications to correct umbilicus malposition after a mini-abdominoplasty. Over a period of 24 months, 12 patients underwent a liposuction (suction-assisted liposuction) and abdominoplasty with horizontal supraumbilical muscle plication. All patients underwent objective measurements before and after the procedure, using digital image measurements by Mirror Image software, version 6.0 (Fairfield, N.J.). The follow-up evaluation was performed 12 months postoperatively. Statistical analysis was performed using IBM SPSS Statistics V26. Over 24 months, 12 patients (100%), who underwent abdominoplasty combined with horizontal plication in the upper abdominal wall, have shown adequate umbilicus elevation (2.98 ± 0.242 cm; 95% confidence level), restoring the abdominal muscle wall proportion at 12 months follow-up. One patient (8%) had a seroma, and one (8%) had a small muscular hernia (1.5 cm) in the lower abdomen. The combination of abdominoplasty and upper horizontal muscle plication can fix the malpositioned umbilicus, restoring the aesthetic and anatomic proportions in those patients who underwent an umbilical float mini-abdominoplasty.

Nonlinear storage–discharge dynamics of forested headwater catchment: A hysteresis index approach

AbstractThe relationship between catchment storage and discharge is nonlinear. The dynamicity of this relationship is dependent on the distance of the storage measurement from the stream, the depth of the soil moisture (SM) measurement, antecedent SM storage, and precipitation characteristics. Understanding the relative influence of these factors is critical for interpreting runoff generation processes and predicting discharge. In this study, we used a hysteresis index approach and analysed the nonlinear dynamics of catchment storage–discharge relationship across points, hillslope and catchment scales, and their controlling factors. A small headwater forested catchment located in the southern part of the Sierra Nevada region, California, was selected as a case study. In this Mediterranean catchment, the anticlockwise class IV hysteresis loop, indicating an earlier discharge peak than SM, was observed as a prevalent hysteresis class across all the scales, irrespective of seasons (i.e., dry vs. wet) and years (i.e., normal vs. drought). A few clockwise hysteresis loops were observed at the shallow depths (10 and 30 cm) of upslope and lower slope topographic positions. Further, we found a shorter lag time between SM peak to discharge peak at 60 and 90 cm soil depths during the wet season, and during the drought period. The shorter lag at the deeper depth was due to the presence of subsurface flow during high antecedent SM storage conditions and preferential flow through the soil pores during the drought periods. The variability in hysteresis at catchment and hillslope scales was controlled by peak rainfall intensity and antecedent SM storage. However, rainfall characteristics (intensity and depth) were major governing factors for most of the point scale locations. Overall, the current study highlighted the role of SM sensor's location in characterizing storage–discharge behaviour.

Pollution Accumulation Simulation of Composite Insulators in Western Inner Mongolia

To study the effect of pollution accumulation on flashover voltage for composite insulators in western Inner Mongolia, COMSOL software was used to simulate the impact of non-uniform pollution deposition, different particle sizes, varying pollution severity levels, and different wind directions on the amount of accumulated pollution and the flashover voltage of composite insulators. The results indicate that after passing through the composite insulator, pollution particles accumulate to varying degrees on the surface, mainly concentrated at the edges of the insulator shed and the ridges of the skirt. The larger the particle size, the more pollutants accumulate on the composite insulator, which leads to a higher degree of distortion in the surface electric field. The accumulation of pollutants under oblique wind conditions is higher than that under horizontal wind conditions, and the lower skirt position of composite insulators is more prone to accumulation. The non-uniform distribution of pollution on composite insulators leads to an uneven distribution of the surface electric field upon energization, thus reducing the flashover voltage of the composite insulator and making it more susceptible to flashover incidents.

Design of Automotive Collision Avoidance Lower Position Controller Based on GA Optimization

Abstract To improve the control stability of the lower controller in the vehicle collision avoidance system, and solve the problem of traditional fuzzy PID not providing good dynamic performance under large parameter changes, a lower controller for vehicle collision avoidance based on genetic algorithm optimized fuzzy proportional-integral-derivative (PID) control was studied. The vehicle collision avoidance system collects real-time motion information of the preceding vehicle through millimeter-wave radar and calculates the safety distance. The safety distance model and upper controller of the system calculate the required acceleration of the vehicle. Afterwards, the expected acceleration of the vehicle is controlled by the lower controller of fuzzy PID. At the same time, the improved GA is used to adjust the PID parameters, solving the problem of poor robustness of the lower controller. A simulation platform was built to simulate the longitudinal vehicle collision avoidance control system jointly. The simulation results show that the lower controller designed based on this control algorithm has better stability and meets the collision avoidance requirements, providing an important basis for the development of vehicle control systems.

Do textbooks reflect learners’ diversity? A case study of Grade 4 English and life skills textbooks

Textbooks socialise and legitimise cultural norms, and therefore, learners’ social worlds should find expression in their textbooks. In the study reported on here we examined how Grade 4 English First Additional Language and life skills textbooks reflected learner diversity in South African schools as manifested in their racial, gender, occupational, ability and geographical profiling in the textbooks. Content analysis was used to systematically identify instances of diversity representation in Grade 4 English First Additional Language and life skills textbooks. Quantitative content analysis accounted for the ubiquity of human characters’ reflection in textbooks on the diversity variables in question. Qualitative analysis focused on the depiction of characters’ gender roles. Quantitative data suggest that learners’ social worlds were generally represented in the selected textbooks. However, males enjoyed greater visibility than females, and the visibility of disabled people was low. The 2 life skills and 1 English textbook portrayed both urban and rural settings. The qualitative analysis uncovered some gender stereotyping, where, for example, women were depicted in lower positions compared to men’s high-paying vocations like judges, scientists, or doctors. Boys were depicted receiving prizes for their Matric achievements. Implications for publishers and writers commissioned to write textbooks include the need to consider representation of learner diversity in textbooks. The Department of Education should develop guidelines that promote such representation.

Effects of the low Fowler's sleep position and methazolamide treatment on sleep bruxism: A randomized controlled trial.

Intracranial pressure is one of the determinants of sympathetic activities, and sleep bruxism is associated with increased sympathetic activities. This study aimed to investigate effects of the low Fowler's sleep position and methazolamide treatment on the occurrence of rhythmic masticatory muscle activities/sleep bruxism episodes in patients with sleep bruxism in a randomized controlled trial. Polysomnographic recordings were performed on the patients with sleep bruxism sleeping in the low Fowler's (15°-30°) or supine position (n = 11), and with methazolamide or placebo treatment (100 mg, 3-4 hr before bedtime, P.O., n = 9), and changes in sleep variables and heart rate variance during sleep in the low Fowler's position or with methazolamide treatment were determined. Sleep bruxism index, number of masseter muscle electromyographic bursts per hour of sleep, ratio of rhythmic masticatory muscle activities/sleep bruxism duration to the total sleep duration, index of total limb movements, index of limb movements with rhythmic masticatory muscle activities, and number of sleep bruxism clusters per hour of sleep in the low Fowler's position and after methazolamide intake were significantly smaller (p < 0.05-0.001) than those in the supine position and after placebo intake, respectively. The low-frequency heart rate variance powers during non-rapid eye movement sleep stage 2 (N2) in the low Fowler's position and with methazolamide treatment were significantly lower (p < 0.05) than those during sleep in the supine position and with placebo treatment, respectively. In conclusion, sleep in the low Fowler's position and methazolamide treatment were associated with significant decreases in the occurrence of rhythmic masticatory muscle activities/sleep bruxism episodes, which might be due to a reduction in intracranial pressure and sympathetic activities mainly during non-rapid eye movement sleep stage 2.

Silver Recovery from Crystalline Silicon Photovoltaic Solar Cells Using Continuous Stirred-Tank Reactors.

Silver can be recycled from the end-of-life crystalline silicon photovoltaic (PV), yet the recycling and its technology scale-up are still at an early stage especially in continuously operations e.g., continoursely stirred tank reactors (CSTR). Here, the silver recovery from the solar cells is technically understood and optimized in the CSTR system from the point of view of silver recovery efficiency, through integrating experimental and numerical investigations. Specifically, based on the experiments, a kinetics model is developed and scanning electron microscopy surface morphology is characterized; and a computational fluid dynamics-discrete element method (CFD-DEM) particle-scale model is integrated with the kinetics model and validated against the fluid-flow pattern and silver leaching performance results from lab measurements. The validated CFD-DEM model is then applied to understand the particle-scale behavior of silver leaching in the CSTR system in terms of hydrodynamics and AgNO3 distribution under different impeller speeds. The simulation results show that the silver leaching performance is improved in an improved CSTR design with a lower impeller position and doubled impeller layers. This work reveals the effectiveness and underlying hydrodynamics of silver leaching in CSTR systems and lays a foundation for improving silver recovery in PV recycling.

Racial and ethnic diversity in academic nursing leadership: A cross-sectional analysis

Background/PurposeTo characterize the representation of racial and ethnic minoritized faculty in leadership positions at the top 50 National Institutes of Health-ranked academic nursing institutions. MethodsWe conducted a cross-sectional observational study to characterize the racial/ethnic composition of academic leaders, including those in diversity, equity, and inclusion (DEI) positions from September 2020 to December 2020. DiscussionAmong the 409 leaders, the sample was predominantly composed of females (86.6%), White leaders (80.9%), affiliated with public institutions (75.1%), and in the southern region (42.1%). Exactly 13.6% were from minoritized groups. Minoritized leaders were less likely to hold dean and higher executive positions than their nonminoritized counterparts (p < .002). DEI leadership positions were mostly concentrated in lower executive positions (e.g., director) and primarily consisted of minoritized leaders (>60%). ConclusionUnderrepresentation of racial and ethnic minoritized individuals in academic nursing leadership persists, necessitating structural interventions within nursing academia to promote inclusivity. Achieving this goal requires a concerted investment in diversifying academic nursing leadership and ensuring positions that minoritized leaders are in, hold weight.

Subjektive Gesundheit in der Frühphase der COVID-19-Pandemie – ein Vergleich von soziodemografischen Gruppen und pandemiebezogenen Risikofaktoren

ZusammenfassungHintergrundIn der Frühphase der COVID-19-Pandemie im Jahr 2020 war der Alltag durch die Eindämmungsmaßnahmen des ersten Lockdowns vergleichsweise stark eingeschränkt, während die SARS-CoV-2-Inzidenzen noch gering ausfielen. Der vorliegende Beitrag analysiert soziodemografische und sozioökonomische Gruppen im Hinblick auf die Beeinträchtigung der subjektiven Gesundheit in dieser Phase.MethodenDaten der Hauptbefragung des Sozio-oekonomischen Panels (n = 14.856, März–Juli 2020) wurden verwendet, um die relative Häufigkeit selbstberichteter guter Gesundheit, großer Sorgen um die eigene Gesundheit und hoher Lebenszufriedenheit von Männern und Frauen stratifiziert nach Alter, Bildung, Einkommen, Migrationserfahrung, Vorerkrankungen und Risikoberufen zu schätzen. Die Ergebnisse wurden mittels logistischer Regressionen wechselseitig adjustiert und monatsweise dargestellt sowie mit der vorpandemischen Zeit verglichen.ErgebnissePersonen in höherem Alter, mit niedriger Bildung oder niedrigem Einkommen sowie mit Vorerkrankungen berichteten seltener positive Gesundheitsoutcomes und häufiger Sorgen. Die Unterschiede zwischen den Merkmalsgruppen blieben im Vergleich zur vorpandemischen Zeit weitgehend stabil. Personen mit niedriger Bildung oder niedrigem Einkommen berichteten im Vergleich zu Personen der mittleren und höheren Bildungs- beziehungsweise Einkommensgruppen zum Zeitpunkt der stärksten Einschränkungen durch Infektionsschutzmaßnahmen seltener eine gute Gesundheit.DiskussionDer Einfluss der Frühphase der Pandemie auf die subjektive Gesundheit und Lebenszufriedenheit ist für den Großteil der untersuchten Gruppen gering. Nur für Frauen in niedrigen sozioökonomischen Positionen konnten relative Verschlechterungen identifiziert werden.

Flow-Induced Vibration Analysis by Simulating a High-Speed Train Pantograph

This paper investigates the aerodynamic behavior and dynamic characteristics of high-speed train pantographs under various operating conditions using advanced aerodynamic simulations and dynamic analyses. The simulations show significant fluctuations in aerodynamic loads during tunnel entry and exit, heavily influenced by train speed and pantograph position (raised/lowered). Modal simulations reveal distinct low-frequency vibrations in pantographs, significantly impacted by external aerodynamic forces. Importantly, the lowered position exposes the pantograph to upward aerodynamic forces, leading to increased bow-net contact force and off-line rate, ultimately compromising current collection stability. Both maximum contact force and off-line rate further increase with higher train speeds. To improve pantograph design, the paper proposes adjustments to the airbag’s equivalent spring stiffness and the bow head’s density. These modifications aim to mitigate contact force and enhance the stability and reliability of pantographs at high speeds. This research offers theoretical and practical insights, aiding in the design, optimization, and refinement of future pantograph systems.

Holocene vegetation and wildfire disturbance in boreal central Yukon, Canada

Sediment cores were collected from Wrong (WL) and Lenore (LL) lakes in boreal central Yukon Territory, Canada, spanning circa 6000 years. Analyses of pollen, charcoal, magnetic susceptibility, levoglucosan, and down-scaled paleoclimatic data reveal the vegetation history and character/drivers of Holocene fire disturbance. Boreal forest has persisted in the region for millennia, with a regional mid-Holocene expansion of Picea mariana followed by expansion of Pinus contorta in the latest Holocene. The shortest reconstructed fire return intervals (FRI; ca. 110-125 years) occurred in the mid-Holocene, coincident with the development of highly flammable Picea-dominated forest and warm, dry summers that were characterized by elevated JJA Z500 anomalies and associated with an eastward/intense Aleutian Low. In the late-Holocene, FRI increased to ca. 240 years at WL and 280 years LL. Drivers of this change include regional cooling and increased precipitation, with a westward/weaker Aleutian Low position delivering more moisture to interior Yukon. Longer FRIs allowed for greater fuel accumulation between fires, enhancing fire size/severity. While higher fire frequency is noted in the mid-Holocene and increased fire size/severity in the late-Holocene, recent changes in Yukon fire disturbance suggest that the fire regime may soon lie outside the natural range of mid- and late-Holocene variability.

Occurrence of the large aquatic snake Palaeophis cf. africanus (Serpentes, Palaeophiidae) in the middle Eocene of the Sabkha El Breij, southwestern Morocco

ABSTRACT We here report an anterior trunk vertebra of a large snake that we tentatively refer to Palaeophis africanus. The vertebra comes from lower middle Eocene deposits of the El Breij Depression, in the Sahara Desert of southern Morocco. It is principally characterised by weak lateral compression; horizontality of the cotyle-condyle axis; dorsoventrally thick zygosphene; lower pterapophyses with an upper edge that remains lower than that of the zygosphene in lateral view; a rather reduced neural canal; very distinct and prominent interzygapophyseal crests; low position of the diapophyses; and the presence of two hypapophyses. This occurrence adds to the geographic distribution of Palaeophis africanus, which has been formerly identified from Nigeria, Togo, Angola, and South America, and represents an additional Palaeophis species for the Moroccan fossil record.

Perceived quality of peer relationships and position in peer network from late childhood to early adolescence: A three-wave longitudinal study with cross-lagged panel model

Objective: The main aim of this study was to investigate the mutual relationship between perceptions of peer relationship quality and position in positive and negative peer networks among young people from late childhood to early adolescence. Method: A cross-lagged panel model of three waves of data was conducted using a large representative sample of Polish students from third grade to sixth grade ( N = 4 673). Results: The results proved a reciprocal relationship between position in positive (Like) and negative (DisLike) peer networks and the perceived quality of peer relationships (PPI). The effect found of position on the perceived quality of peer relationships is in line with the existing state of knowledge. Since previous research has yielded divergent results, this demonstration of the prospective impact of perceived relationship quality on peer network position fills an important cognitive gap. The study also revealed the following: (1) in the first (W1→W2) and second period (W2→W3) the strength of the prospective effects of position in the peer network on its perceived quality (Like→PPI and DisLike→PPI), and the strength of the prospective effects of perceived quality on position (PPI→Like and PPI→DisLike), were not statistically significantly different; (2) the effect size of the cross-lagged coefficients ranged from small to medium; (3) all constructs showed greater stability in the second period than in the first; (4) in both periods stability of PPI was lower than the stability of sociometric indicators. Conclusion: This research confirms the presence of a self-reinforcing loop: a low position in peer networks→poor perceived quality of relations→decrease of position in peer networks. The findings are discussed in relation to the evolutionary theory of loneliness (ETL), which assumes a potentially active role of the perception of peer relationships in forming a position in a peer network. Practical implications of the results are discussed.

Exploring the mechanisms underlying increased risk of depressive disorder in ethnic minority populations in Europe: A causal loop diagram

BackgroundMultiple ethnic minority populations in Europe show high risk of major depressive disorder (MDD), with ethnic discrimination and low socioeconomic position (SEP) as established risk factors. How this risk is shaped by the interactions between these, and other social factors, remains to be elucidated. We aimed to develop a causal-loop diagram (CLD) to gain a better understanding of how factors at the intersection of ethnic discrimination and SEP dynamically interact to drive MDD risk. MethodsWe iteratively mapped the interactions and feedback loops between factors at the intersection of ethnic discrimination and SEP, drawing input from (i) a series of two interviews with a range of MDD domain experts, (ii) an existing CLD mapping the onset of MDD across psychological, biological, and social dimensions at the level of the individual, and (iii) other relevant literature. ResultsThrough tracing the feedback loops in the resulting CLD, we identified ten driving mechanisms for MDD onset in ethnic minorities (two related to ethnic discrimination, SEP, social network and support, and acculturation, as well as one relating to the living environment and self-stigma towards MDD); and four factors that modulate these mechanisms (recent migration, religious affiliation, neighborhood social environment, and public stigma towards MDD). The intersecting nature of ethnic discrimination and SEP, combined with the reinforcing dynamics of the identified driving mechanisms across time- and spatial scales, underscores the excess exposure to circumstances that increase MDD risk in ethnic minorities. ConclusionsWhile this CLD requires validation through future studies, the intersecting and reinforcing nature of the identified driving mechanisms highlights that tackling the high risk of MDD in ethnic minorities may require intervening at multiple targets, from the individual (e.g., psychological interventions targeting negative beliefs or reducing stress) to the societal level (e.g., addressing labor market discrimination).

Insights into temporal and spatial evolutions of air saturation and its effects on nitrobenzene removal during air sparging remediation

Air saturation (Sa) can significantly influence the removal effect during air sparging (AS). However, there have been few studies focused on the temporal and spatial distribution of the Sa, which is adverse to precise remediation of AS technology. In this study, temporal and spatial evolutions of the Sa and its effects on nitrobenzene removal were investigated by the one-dimensional column experiments during AS. Experimental results demonstrated that the variation of Sa at different positions of the aquifer was significantly different with the increase of sparging time under the same air injection rate (Qinj), and the variation of middle and lower position was 0.3%-11.0%, however, the variation of Sa at the upper position was 21.0%-40.0%. When the Qinj was small, the number of airflow channels was little, and the nitrobenzene removal rates at the middle and upper position were low. With the increase of Qinj, the number of airflow channels was many, and the main region of airflow (Trapezium distribution) began to appear at the lower position, and the nitrobenzene removal rate at the upper position was low, which showed that the nitrobenzene removal rate was mainly affected by the spatial and temporal distribution of Sa in AS process. Based on the above, the mathematical model of relationship between nitrobenzene removal rate, sparging time and Sa was established, which was conducive to the accurate design of AS technology in the site application.

Updated dendrochronology and axial variation of climatic sensitivity in Sequoiadendron giganteum

Key messageDendroclimatic sensitivity varies by axial position for Sequoiadendron giganteum: negative correlations with June temperature strengthen with height, while positive correlations with snow water are strongest in the lower trunk.Increment cores collected along trunks of mature Sequoiadendron giganteum provide new and updated ring-width chronologies ideal for assessing how height above ground affects sensitivity of radial growth to climatic variation. Chronologies from 61 living trees at nine locations across the geographic distribution span 1973 yr. Analyses of subsets of 18–44 trees reveal that correlations between radial increments and climate (temperature, water availability) vary with axial position. Negative correlations with maximum and minimum June temperature intensify with height and are strongest at the highest position analyzed (60 m above ground). Sensitivity to the hydroclimate variable of April-1 snow water equivalent is stronger at lower trunk positions (10 m) compared to breast height or the upper trunk, and a similar relationship is identified for the standardized precipitation evapotranspiration index using a 12-month window ending in September. Drought-induced low-growth years computed as radial increment relative to the mean of 10 yr before and after are more weakly expressed at breast height compared to higher on the trunk (10–60 m). Analysis of regional upper (maximum core height = 87 m) versus lower trunk (above buttress) chronologies corroborate differing inter-annual correlations with climate depending on height above ground. Accounting for axial variation in dendroclimatic sensitivity can maximize the quality of environmental reconstructions using tree rings and improve biophysical understanding of Sequoiadendron, especially in the context of an increasingly arid climate.

MR defecography in assessing stress urinary incontinence with or without symptomatic pelvic organ prolapse.

Utilize magnetic resonance defecography (MRD) to analyze the primary pelvic floor dysfunctions in patients with stress urinary incontinence (SUI) associated with pelvic organ prolapse (POP), and in SUI patients with asymptomatic POP. We performed MRD in both SUI and POP subjects. As a primary analysis, the functional MR parameters were compared between the isolated POP and POP combined SUI groups. As a secondary analysis, the functional MR data were compared between the POP combined SUI and the SUI with asymptomatic POP (isolated SUI) groups. MRD noted the main characteristics of SUI combined moderate or severe POP, including the shorter closed urethra length (1.87cm vs. 2.50cm, p < 0.001), more prevalent urethral hypermobility (112.31° vs. 85.67°, p = 0.003), bladder neck funneling (48.28% vs. 20.51%, p = 0.020), lower position of vesicourethral junction (2.11cm vs. 1.67cm, p = 0.030), and more severe prolapse of the posterior bladder wall (6.26cm vs. 4.35cm, p = 0.008). The isolated SUI patients showed the shortest length of the closed urethra (1.56cm vs. 1.87cm, p = 0.029), a larger vesicourethral angle (153.80° vs. 107.58°, p < 0.001), the more positive bladder funneling (84.85% vs. 48.28%, p = 0.002) and a special urethral opening sign (45.45% vs. 3.45%, p < 0.001). Patients with SUI accompanying POP primarily exhibit excessive urethral mobility and a shortened urethral closure. SUI patients with asymptomatic POP mainly show dysfunction of the urethra and bladder neck, characterized by the opening of the urethra and bladder neck and a shortened urethral closure.

Combined different luminescence dating approaches on fluvial gravel deposits from the southern upper Rhine graben

In recent years, luminescence dating has witnessed significant advancements to overcome its traditional boundaries. However, methodological challenges persist when dating high-energy fluvial gravel deposits in proglacial settings, because partial bleaching and the scarcity of sand lenses complicate luminescence age estimation through conventional approaches. To address these issues, using rock surfaces of large clasts may overcome the limited availability of sand layers in some deposits and allow clast specific assessment of luminescence signal resetting at the time of deposition through the analyses of bleaching profiles. The Hartheim gravel pit in the southern Upper Rhine Graben of southwest Germany features a sedimentary succession deposited by distal braided river meltwater streams reworked during the late Pleistocene. Different luminescence approaches have been applied to sand lenses, the sandy matrix of gravel deposits and crystalline cobbles. Quartz optically stimulated luminescence (OSL) ages range between ∼19 and 22 ka, which represents the time just after the last glaciation maximum in the region. The OSL ages of the sandy matrix of ∼24–27 ka are in an agreement with the previous estimates, as these are from a stratigraphic lower position. However, post-IR infrared stimulated luminescence (pIRIR) ages of sand layer and sandy matrix both are some 3–6 ka older than the OSL ages, despite being internally very consistent. Luminescence depth profiles show that the signal was deeply reset in some cobbles, whereas in others only the IRSL signal in the surface layer appears to have been reset. The cobble IRSL ages show a relatively large spread, and it remains uncertain, if this is caused by incomplete bleaching or it reflects dosimetric issues. Nevertheless, overall, our results underscore the potential of rock surface luminescence dating to date fluvial deposits from the Upper Rhine Graben and similar settings.

Ultrasound-based horizontal ranging in the localization of fetal conus medullaris.

Currently, there are a variety of methods for ultrasound to localize the conus medullaris. A concern is that measured values can be influenced by variations in spinal flexion and extension. To overcome this limitation, the present study measures the horizontal distance (HD) between the end of the conus medullaris and the caudal edge of last vertebral body ossification in normal fetus at different gestational weeks, and analyzes the relationship between the measured value and fetal growth, as well as the utility of these measurements in assessing the position of the conus medullaris. A total of 655 fetuses at gestational weeks 18-40, who underwent routine prenatal ultrasound, were selected in the study. We measured the distance between the end of the cone of the fetal spinal cord and the caudal end of the final vertebral ossification center (Distance1, D1), the distance between the end of the spinal cord cone and the intersection of the extension of D1 with the caudal skin (Distance2, D2), and HD. We analyzed the correlation between the measurements and gestational weeks, established normal reference values, the ratio of D1, D2 and HD to the commonly used growth parameters was calculated. The ratios of D1, D2, HD and the application value of each ratio phase were analyzed, and the reliability analysis of repeated measurement results among physicians was performed. D1, D2 and HD exhibited strong linear correlations with gestational weeks. Among the ratios of D1, D2 and HD to common growth parameters, D2/FL stabilized after 20 weeks of gestation and consistently exceeded 1. Repeatability tests between D1, D2 and HD showed good reliability (P> 0.05). D1, D2 and HD are significantly correlated with gestational age. Horizontal distance measurement can effectively determine the position of fetal conus medullaris, enabling rapid prenatal evaluation of low position of conus medullaris and excluding the possibility of tethered cord.

Serial Change in Patellar Height after Tension Band Wiring of Patellar Fractures.

Background and Objectives: Patella baja is a common complication after operative treatment for patellar fracture. This study aimed to investigate (1) the serial changes in patellar height and (2) the potential predictive factors for patellar height changes after tension band wiring (TBW) for patellar fractures. Materials and Methods: Forty-one patients who underwent TBW for patellar fracture between March 2019 and September 2022 were enrolled. To identify serial changes in patellar height, modified Blackburne-Peel index (mBPI) was assessed at just after surgery, at 3 months, at 6 months, at 1 year and at the final follow-up. Multiple regression analysis was conducted to identify factors correlated with mBPI difference between the contralateral side (considered as preoperative status) and injured side. Results: The postoperative mBPI exhibited a decline over time (mean mBPI immediately post operation/3 months/6 months/1 year/final follow-up: 0.69/0.63/0.63/0.62/0.61) Specifically, mBPI showed a significant reduction immediately post operation to 3 months (p < 0.001), although comparisons at other time points did not reveal significant differences. A lower position of the fracture was associated with a decrease in patellar height after surgery. Conclusions: Patellar height was mainly decreased from immediately post operation to 3 months. A fracture in a lower position of associated with decreased patellar height after the TBW of the transverse patellar fracture.