Change In Direction Research Articles

Hydrodynamic characteristics of a ducted tidal turbine in yawed conditions

In marine environments, tidal currents exhibit periodic changes in both direction and velocity. Consequently, tidal turbines often operate under yawed conditions. While conventional horizontal-axis turbines show decreased performance and undergo periodic load fluctuations due to blade rotation when yawed, research on the effects of yaw on ducted turbines has been sparse, leaving the underlying impact mechanisms poorly understood. This paper presents a three-dimensional hydrodynamic model of a ducted turbine, developed using the computational fluid dynamics method and validated through flume experiments. The hydrodynamic characteristics of the ducted turbine when operating under yawed conditions are analyzed using large eddy simulation. The findings indicate that yaw does not alter the optimal rotational speed of the ducted turbine. The turbine performance remains superior to non-yawed conditions up to a yaw angle of approximately 7°, peaking with a 1% improvement at 5°, but deteriorates beyond this point, declining by 1.5% at a yaw angle of 10°. In addition, yaw causes a deflection in the wake of the ducted turbine. This deflection increases with the yaw angle, reaching its maximum at a yaw angle of 10° with an angle of about 3.4°, before diminishing. The duct structure significantly influences this deflection, while rotor rotation has a minimal impact on wake deflection.

Sea surface temperature budget in Indonesian seas: the role of vertical turbulent flux and its east–west variations

Abstract The vertical turbulent flux, which comprises heat flux and vertical mixing, is one of key processes governing seawater temperature changes in the vertical direction. In this study, the influence of vertical turbulent flux on sea surface temperature (represented by a layer between the free-surface and approximately 20 m depth) in Indonesian seas was diagnosed from an eddy-permitting ocean modeling experiment result. The heat flux, as the sum of the net heat flux at the surface and penetrative shortwave radiation at the base of the surface layer, induced a net cooling tendency in both eastern and western Indonesia (represented by the Java Sea and Banda Sea, respectively). The cooling tendency due to the heat flux was opposed by the warming tendency induced by vertical mixing at the base of the surface layer, preventing excessive heat loss in the surface layer. An exception occurred during the Boreal Autumn in the Banda Sea, when the heat flux and vertical mixing resulted in warming and cooling tendencies, respectively. It was further found that the effect of vertical mixing on the surface layer heat budget was sensitive to the selection of the base layer depth, highlighting the mixing-related dynamic variation within the water column. In summary, this study provides additional insights into the near-surface dynamics that govern sea surface temperature seasonality in Indonesian Seas.

Data-driven wind turbine sensor health validation

This paper presents a data-driven approach for detecting anomalies in wind turbine sensors, specifically anemometers and wind vanes, and the development of a smart alerting system. The study focuses on utilizing SCADA and reanalysis (ERA5) data for accurate anomaly detection and reducing false alarms through smart change point detection algorithms. The methodology involves modeling normal behavior, detecting change points, and comparing power curves before and after these points. For anemometer anomaly detection, a three-year SCADA dataset from an offshore wind farm and a synthetic dataset is used, employing an XGBoost model and the PELT algorithm for change point detection. Wind vane anomalies are identified using a nine month dataset from seven turbines, with synthetic alterations to simulate misalignments. Results show successful detection of sudden changes in wind speed and direction, with smart alarms assisting operators in decision-making. This research enhances wind turbine condition monitoring, improving reliability and efficiency.

Proteome profiling of Campylobacter jejuni 81–176 at 37 °C and 42 °C by label-free mass spectrometry

BackgroundThe main natural reservoir for Campylobacter jejuni is the avian intestinal tract. There, C. jejuni multiplies optimally at 42 °C – the avian body temperature. After infecting humans through oral intake, the bacterium encounters the lower temperature of 37 °C in the human intestinal tract. Proteome profiling by label-free mass spectrometry (DIA-MS) was performed to examine the processes which enable C. jejuni 81–176 to thrive at 37 °C in comparison to 42 °C. In total, four states were compared with each other: incubation for 12 h at 37 °C, for 24 h at 37 °C, for 12 h at 42 °C and 24 h at 42 °C.ResultsIt was shown that the proteomic changes not only according to the different incubation temperature but also to the length of the incubation period were evident when comparing 37 °C and 42 °C as well as 12 h and 24 h of incubation. Altogether, the expression of 957 proteins was quantifiable. 37.1 − 47.3% of the proteins analyzed showed significant differential regulation, with at least a 1.5-fold change in either direction (i.e. log2 FC ≥ 0.585 or log2 FC ≤ -0.585) and an FDR-adjusted p-value of less than 0.05. The significantly differentially expressed proteins could be arranged in 4 different clusters and 16 functional categories.ConclusionsThe C. jejuni proteome at 42 °C is better adapted to high replication rates than that at 37 °C, which was in particular indicated by the up-regulation of proteins belonging to the functional categories “replication” (e.g. Obg, ParABS, and NapL), “DNA synthesis and repair factors” (e.g. DNA-polymerase III, DnaB, and DnaE), “lipid and carbohydrate biosynthesis” (e.g. capsular biosynthesis sugar kinase, PrsA, AccA, and AccP) and “vitamin synthesis, metabolism, cofactor biosynthesis” (e.g. MobB, BioA, and ThiE). The relative up-regulation of proteins with chaperone function (GroL, DnaK, ClpB, HslU, GroS, DnaJ, DnaJ-1, and NapD) at 37 °C in comparison to 42 °C after 12 h incubation indicates a temporary lower-temperature proteomic response. Additionally the up-regulation of factors for DNA uptake (ComEA and RecA) at 37 °C compared to 42 °C indicate a higher competence for the acquisition of extraneous DNA at human body temperature.

Adaptivity of a leaf-inspired wind energy harvester with respect to wind speed and direction

Environmental wind is a random phenomenon in both speed and direction, though it can be forecasted to some extent. An example of that is a gust which is an abrupt, but short-time change in wind speed and direction. Being a free and clean source for small-scale energy scavenging, attraction of wind is rapidly growing in the world of energy harvesters. In this paper, a leaf-like flapping wind energy harvester is introduced as the base structure in which a short-span airfoil is attached to the free end of a double-deck cantilever beam. A flap mechanism inspired by scales on sharks’ skin and a tail mechanism inspired by birds’ horizontal tail are proposed for integration to the base harvester to make it adaptive with respect to wind speed and direction, respectively. The use of the flap mechanism increases the leaf flapping frequency by +2.1 to +11.5 Hz at wind speeds of 1.5 to 6.0 m s−1. Therefore, since the output power of a vibrational harvester is a function of vibration frequency, a figure of merit or an efficiency parameter related to the output power will increase, as well. On the other hand, if there is a misalignment between the harvester’s heading and wind direction due to change of the latter one, the harvesting performance deteriorates. Although the base harvester can realign in certain ranges of sideslip angle at each wind speed, when the tail mechanism is integrated into that, it broadens the range of realignable sideslip angles at all the investigated wind speeds by up to 80 ∘ .

Skin Cancer Segmentation using CNN

This groundbreaking research introduces a comprehensive strategy for advancing medical image segmentation, merging two pivotal concepts to significantly enhance both the accuracy and efficiency of the segmentation process. The first component of our approach involves the integration of polar transformations as a preprocessing step applied to the original dataset. This transformative technique is designed to address the challenges associated with segmenting single structures of elliptical shape in medical images, such as organs (e.g., heart and kidneys), skin lesions, polyps, and various abnormalities. By centering the polar transformation on the object's focal point, a reduction in dimensionality is achieved, coupled with a distinct separation of segmentation and localization tasks. Two distinct methodologies for selecting an optimal polar origin are proposed: one involving estimation through a segmentation neural network trained on non-polar images, and the other employing a dedicated neural network trained to pre dict the optimal origin. The second key element of our approach is around the integration of the DoubleU-Net architecture, a powerful encoder-decoder model specifically designed for the task of semantic image segmentation. DoubleU- Net is a group of two U-Net architectures, each with a specific purpose. The initial U-Net is pre-trained on VGG-19 as the encoder and uses features learned from ImageNet to provide efficient information transfer. In order to store more semantic information and content, a second U-Net was added to the base to enhance the capabilities of the network. Join Atrous Spatial Pyramid Pooling (ASPP) to develop network data extraction content. The combination of DoubleU-Net architecture and joint transformation as a step forward shows good segmentation performance in different clinical tasks, including liver segmentation, polyp detection vision, skin segmentation, and epicardial fat tissue segmentation. It shows that various medical projects, including various diagnostic methods such as colonoscopy, dermoscopy, microscopy, have a positive impact on the plan. More importantly, the method performs well in difficult cases, such as the segmentation of small and flat polyps in CVC-ClinicDB and the 2015 subset of the MICCAI Automated Polyp Detection dataset. The results demonstrate the accuracy and generality of the combination, making it the best way to evaluate medical images in context; Our study has revealed a new method of skin cancer diagnosis that combines the power of deep learning with innovation. Advanced technology. The combination of dual U-Net architecture and polar coordinate transformation not only improves the accuracy of classification of lesions but also improves the robustness of the model to changes in image features. This study contributes to the development of computer-aided diagnostic systems for early diagnosis. Experimental results show that our method provides good accuracy, sensitivity, and specificity in detecting malignant and benign tumors. Additionally, we are conducting ablation studies to determine the contribution of each presentation and treatment of skin cancer to ultimately benefit patients and determine these benefits. We also apply the transformation of the joint as the first step to improve the discrimination ability of the model. This mechanical change effectively reduces the impact caused by changes in wound size, shape, and direction by displaying the original image of the polar system. By standardizing the representation of skin diseases, polar transformation improves the model's ability to generalize across different data sets and improves overall performance.

Electronic transport properties in GaAs/AlGaAs finite superlattice of cylindrical quantum wires

In this paper, we have studied a theoretical and numerical investigation of the electronic properties of finite cylindrical quantum wires (CQWRs), constituted by the periodic alteration of two semiconductor materials of CQWRs GaAs/AlGaAs in the axial direction, the structure sandwiched between two substrates GaAs. The electronic band structure and the electronic transmission spectrum are obtained by means of Green’s function approach, taking into account the impact of connection barriers. Our results reveal that the electronic energy levels of CQWRs consist of alternating passbands and bandgaps. The coincidence of incoming electronic waves with these discrete electronic energy levels leads to electron transport during the CQWRs superlattice. We employed an effective mass model dependent on the cell position in the axial direction to solve the Schrodinger equation. This model was adjusted to reflect variations in the confining potentials while accounting for changes in the radial direction. When the radius of the structure is relatively small the electronic states tend towards higher energies due to geometrical confinement. On the other hand, as the radius increases, the passbands and bandgaps move to lower energies. Similarly, the pseudogaps turn into full gaps, and their width increases, and this feature is also observed when the number of cells increases. This property is due to the interaction between the neighboring electrons and the eigenstates of the CQWRs. In addition, the passbands and band gaps shift to high energy when the barrier concentration increases, and the width of band gaps increases also. Finally, we have demonstrated the theoretical design of an optoelectronic device for filtering electronic waves by geometrical and physical parameters, whose electronic band structure of this finite CQWRs superlattice can be controlled.

Design and Validation of the Trailing Edge of a Variable Camber Wing Based on a Two-Dimensional Airfoil.

Variable camber wing technology stands out as the most promising morphing technology currently available in green aviation. Despite the ongoing advancements in smart materials and compliant structures, they still fall short in terms of driving force, power, and speed, rendering mechanical structures based on kinematics the preferred choice for large long-range civilian aircraft. In line with this principle, this paper introduces a linkage-based variable camber trailing edge design approach. Covering coordinated design, internal skeleton design, flexible skin design, and drive structure design, the method leverages a two-dimensional supercritical airfoil to craft a seamless, continuous two-dimensional wing full-size variable camber trailing edge structure, boasting a 2.7 m span and 4.3 m chord. Given the significant changes in aerodynamic load direction, ground tests under cruise load utilize a tracking-loading system based on tape and lever. Results indicate that the designed single-degree-of-freedom Watt I mechanism and Stephenson III drive mechanism adeptly accommodate the slender trailing edge of the supercritical airfoil. Under a maximum cruise vertical aerodynamic load of 17,072 N, the structure meets strength requirements when deflected to 5°. The research in this paper can provide some insights into the engineering design of variable camber wings.

Influences of damping, perturbation and variable coefficient on an extended nonlinear Gardner model

Describing the nonlinear wave propagation in fluids has posed a challenging task. The nonlinear Gardner equation stands as a crucial model in fluid dynamics. An extended Gardner model incorporates variable coefficients, damping, and perturbation terms, offering a more comprehensive approach to understanding complex wave dynamics in fluids. In our study, we employ the symbolic computation tool, specifically the Darboux transformation, to derive new analytic solutions up to the Nth order for this extended Gardner equation. By assigning the spectrum parameters in these solutions into real values, we are able to obtain line-like solitons. Moreover, when N⩾2 and pairs of complex conjugate values are assigned to two of the spectrum parameters, breathers emerge. This enables a comprehensive analysis of the dynamics involving solitons, breathers, and their hybrid forms, shedding light on their interactions. Furthermore, our work introduces several noteworthy insights by investigating the influences of three key factors: the damping, perturbation, and variable coefficient. Through a few of specific examples, we can confirm the following facts: (i) The damping factor plays a crucial role in rendering solitons and breathers unstable, causing them to undergo exponential changes in both amplitudes and directions during propagation. (ii) The perturbation function creates non-zero background waves along the time axis, which interact with solitons and breathers. (iii) The variable coefficient can introduce disturbances to solitons and breathers. Our findings disclose that this equation exhibits a wealth of intricate propagation patterns. Various factors can exert varying degrees of influence on solitons and their dynamics. This observation just underscores the complexity inherent in the real world and should be useful in applications.

Not seeing the forest for the trees: combination of path integration and landmark cues in human virtual navigation.

In order to successfully move from place to place, our brain often combines sensory inputs from various sources by dynamically weighting spatial cues according to their reliability and relevance for a given task. Two of the most important cues in navigation are the spatial arrangement of landmarks in the environment, and the continuous path integration of travelled distances and changes in direction. Several studies have shown that Bayesian integration of cues provides a good explanation for navigation in environments dominated by small numbers of easily identifiable landmarks. However, it remains largely unclear how cues are combined in more complex environments. To investigate how humans process and combine landmarks and path integration in complex environments, we conducted a series of triangle completion experiments in virtual reality, in which we varied the number of landmarks from an open steppe to a dense forest, thus going beyond the spatially simple environments that have been studied in the past. We analysed spatial behaviour at both the population and individual level with linear regression models and developed a computational model, based on maximum likelihood estimation (MLE), to infer the underlying combination of cues. Overall homing performance was optimal in an environment containing three landmarks arranged around the goal location. With more than three landmarks, individual differences between participants in the use of cues are striking. For some, the addition of landmarks does not worsen their performance, whereas for others it seems to impair their use of landmark information. It appears that navigation success in complex environments depends on the ability to identify the correct clearing around the goal location, suggesting that some participants may not be able to see the forest for the trees.

Experimental investigation of photoelectrical performance and thermal characteristics of ventilated building-integrated photovoltaic system utilizing lightweight and flexible crystalline silicon module

The existing large-scale of industrial buildings with lightweight insulated roofing structures presents a challenge for traditional glass crystalline silicon photovoltaic (PV) systems due to insufficient load-bearing capacity. Meanwhile, traditional PV rooftop applications also face challenges due to limited rooftop resources. To address these issues, this study proposes a ventilated building-integrated lightweight photovoltaic (VL-BIPV) system. The VL-BIPV system incorporates lightweight and flexible crystalline silicon modules, which increase rooftop load by about 6 kg/m2. Additionally, the system features a ventilation channel design to enhance thermal management performance. To evaluate the PV performance and thermal characteristics of the proposed system, an experimental setup was implemented to compare the performances of the VL-BIPV system with a building-attached lightweight photovoltaic (L-BAPV) system that utilizes color steel sheet base plates. The results demonstrate the exceptional performance of VL-BIPV system, with a 100.56% higher ratio of the product of short-circuit current and open-circuit voltage compared to L-BAPV. Moreover, the VL-BIPV system achieved a 1.77% increase in PV efficiency and a 2.35% enhancement in daily electricity generation. In hot weather, the adoption of VL-BIPV reduced the extreme temperature of PV cells by 9.23 °C below 85 °C, surpassing the 6.29 °C reduction achieved by L-BAPV system. Furthermore, the ventilation channel exhibited a gradual temperature increase with slower changes in the flow direction, while the base plate temperature decreased by 13.41 °C, which indicates that VL-BIPV can effectively reduce solar heat gain in the building envelope and improve the indoor thermal environment. The research findings provide important guidance for promoting and applying VL-BIPV technology in large-scale industrial buildings with low rooftop load-bearing capacity, thereby promoting the production and utilization of clean electricity in industrial parks.

Numerical Modeling of Flow in the Cerebral Vasculature: Understanding Changes in Collateral Flow Directions in the Circle of Willis for a Cohort of Vasospasm Patients Through Image-Based Computational Fluid Dynamics.

The Circle of Willis (CoW) is a ring-like network of blood vessels that perfuses the brain. Flow in the collateral pathways that connect major arterial inputs in the CoW change dynamically in response to vessel narrowing or occlusion. Vasospasm is an involuntary constriction of blood vessels following subarachnoid hemorrhage (SAH), which can lead to stroke. This study investigated interactions between localization of vasospasm in the CoW, vasospasm severity, anatomical variations, and changes in collateral flow directions. Patient-specific computational fluid dynamics (CFD) simulations were created for 25 vasospasm patients. Computed tomographic angiography scans were segmented capturing the anatomical variation and stenosis due to vasospasm. Transcranial Doppler ultrasound measurements of velocity were used to define boundary conditions. Digital subtraction angiography was analyzed to determine the directions and magnitudes of collateral flows as well as vasospasm severity in each vessel. Percent changes in resistance and viscous dissipation were analyzed to quantify vasospasm severity and localization of vasospasm in a specific region of the CoW. Angiographic severity correlated well with percent changes in resistance and viscous dissipation across all cerebral vessels. Changes in flow direction were observed in collateral pathways of some patients with localized vasospasm, while no significant changes in flow direction were observed in others. CFD simulations can be leveraged to quantify the localization and severity of vasospasm in SAH patients. These factors as well as anatomical variation may lead to changes in collateral flow directions. Future work could relate localization and vasospasm severity to clinical outcomes like the development of infarct.

Brownfield modifications to convert existing gas production facilities for CCS operations

In recent years, traditional oil and gas operators have found novel means of extending the life of their assets and deferring onerous decommissioning costs by converting their facilities from gas production into carbon dioxide (CO2) injection. While the task of designing for CO2 may sound simple, CO2 injection works in counter-intuitive ways, with previously established heuristics derived from years of experience in gas condensate systems being quickly challenged as potentially dangerous. The world of designing CO2 systems is back-to-front compared with hydrocarbons; it isn’t simply a case of a change in flow direction. Some of the design challenges explored in this paper include: large density variability in CO2 systems where a small change in the ambient temperature can significantly impact the pressure of a shut-in system; optimal pressure ratings of the vents and drains systems and how previous safety margins may be unsafe; pipeline hydraulic modelling focussed on new areas outside of the traditional suite of analysis, such as assurance of the supercritical phase; understanding liquid water dropout being more of a concern than hydrate formation; injection wells counter-intuitively flowing from low pressure to high pressure; whether to vent CO2 above or below an offshore platform; and optimal liquefied CO2 storage vessel conditions and safeguarding.

Reconstructing dynamics of the Baltic Ice Stream Complex during deglaciation of the Last Scandinavian Ice Sheet

Abstract. Landforms left behind by the last Scandinavian Ice Sheet (SIS) offer an opportunity to investigate controls governing ice sheet dynamics. Terrestrial sectors of the ice sheet have received considerable attention from landform and stratigraphic investigations. In contrast, despite its geographical importance, the Baltic Sea remains poorly constrained due to limitations in bathymetric data. Both ice-sheet-scale investigations and regional studies at the southern periphery of the SIS have considered the Baltic depression to be a preferential route for ice flux towards the southern ice margin throughout the last glaciation. During the deglaciation the Baltic depression hosted the extensive Baltic Ice Lake, which likely exerted a considerable control on ice dynamics. Here we investigate the Baltic depression using newly available bathymetric data and peripheral topographic data. These data reveal an extensive landform suite stretching from Denmark in the west to Estonia in the east and from the southern European coast to the Åland Sea, comprising an area of 0.3 million km2. We use these landforms to reconstruct aspects of the ice dynamic history of the Baltic sector of the ice sheet. Landform evidence indicates a complex retreat pattern that changes from lobate ice margins with splaying lineations to parallel mega-scale glacial lineations (MSGLs) in the deeper depressions of the Baltic Basin. Ice margin still-stands on underlying geological structures indicate the likely importance of pinning points during deglaciation, resulting in a stepped retreat signal. Over the span of the study area we identify broad changes in the ice flow direction, ranging from SE–NW to N–S and then to NW–SE. MSGLs reveal distinct corridors of fast ice flow (ice streams) with widths of 30 km and up to 95 km in places, rather than the often-interpreted Baltic-wide (300 km) accelerated ice flow zone. These smaller ice streams are interpreted as having operated close behind the ice margin during late stages of deglaciation. Where previous ice-sheet-scale investigations inferred a single ice source, our mapping identifies flow and ice margin geometries from both Swedish and northern Bothnian sources. We anticipate that our landform mapping and interpretations may be used as a framework for more detailed empirical studies by identifying targets to acquire high-resolution bathymetry and sediment cores and also for comparison with numerical ice sheet modelling.

Geometrical multiscale tortuosity of desert ant walking trajectories.

Desert ants stand out as some of the most intriguing insect navigators, having captured the attention of scientists for decades. This includes the structure of walking trajectories during goal approach and search behaviour for the nest and familiar feeding sites. In the present study, we analysed such trajectories with regard to changes in walking direction. The directional change of the ants was quantified, i.e. an angle θ between trajectory increments of a given arclength λ was computed. This was done for different length scales λ, according to our goal of analysing desert ant path characteristics with respect to length scale. First, varying λ through more than two orders of magnitude demonstrated Brownian motion characteristics typical of the random walk component of search behaviour. Unexpectedly, this random walk component was also present in - supposedly rather linear - approach trajectories. Second, there were small but notable deviations from a uniform angle distribution that is characteristic of random walks. This was true for specific search situations, mostly close to the (virtual) goal position. And third, experience with a feeder position resulted in straighter approaches and more focused searches, which was also true for nest searches, albeit to a lesser extent. Taken together, these results both verify and extend previous studies on desert ant path characteristics. Of particular interest are the ubiquitous Brownian motion signatures and specific deviations thereof close to the goal position, indicative of unexpectedly structured search behaviour.

High certainty evidence is stable and trustworthy, whereas evidence of moderate or lower certainty may be equally prone to being unstable

ObjectivesTo assess to what extent the overall quality of evidence indicates changes to observe intervention effect estimates when new data become available. MethodsWe conducted a meta-epidemiological study. We obtained evidence from meta-analyses of randomized trials of Cochrane reviews addressing the same health-care question that was updated with inclusion of additional data between January 2016 and May 2021. We extracted the reported effect estimates with 95% confidence intervals (CIs) from meta-analyses and corresponding GRADE (Grading of Recommendations Assessment, Development, and Evaluation) assessments of any intervention comparison for the primary outcome in the first and the last updated review version. We considered the reported overall quality (certainty) of evidence (CoE) and specific evidence limitations (no, serious or very serious for risk of bias, imprecision, inconsistency, and/or indirectness). We assessed the change in pooled effect estimates between the original and updated evidence using the ratio of odds ratio (ROR), absolute ratio of odds ratio (aROR), ratio of standard errors (RoSE), direction of effects, and level of statistical significance. ResultsHigh CoE without limitations characterized 19.3% (n = 29) out of 150 included original Cochrane reviews. The update with additional data did not systematically change the effect estimates (mean ROR 1.00; 95% CI 0.99–1.02), which deviated 1.06-fold from the older estimates (median aROR; interquartile range [IQR]: 1.01–1.15), gained precision (median RoSE 0.87; IQR 0.76–1.00), and maintained the same direction with the same level of statistical significance in 93% (27 of 29) of cases. Lower CoE with limitations characterized 121 original reviews and graded as moderate CoE in 30.0% (45 of 150), low CoE in 32.0% (48 of 150), and very low CoE in 18.7% (28 of 150) reviews. Their update had larger absolute deviations (median aROR 1.12 to 1.33) and larger gains in precision (median RoSE 0.78–0.86) without clear and consistent differences between these categories of CoE. Changes in effect direction or statistical significance were also more common in the lower quality evidence, again with a similar extent across categories (without change in 75.6%, 64.6%, and 75.0% for moderate, low, very low CoE). As limitations increased, effect estimates deviated more (aROR 1.05 with zero, 1.11 with one, 1.25 with two, 1.24 with three limitations) and changes in direction or significance became more frequent (93.2% stable with no limitations, 74.5% with one, 68.2% with two, and 61.5% with three limitations). ConclusionHigh-quality evidence without methodological deficiencies is trustworthy and stable, providing reliable intervention effect estimates when updated with new data. Evidence of moderate and lower quality may be equally prone to being unstable and cannot indicate if available effect estimates are true, exaggerated, or underestimated.

Midcrustal moderate-size earthquake occurrence in paleovolcanic structures off Jeju Island, South Korea

A series of midcrustal moderate-size earthquakes occurred in the Korean Peninsula recently. A midcrustal ML4.9 strike-slip earthquake with a fault-plane strike in N-S occurred on December 14, 2021 at the southwestern offshore region of Jeju Island, South Korea. The fault plane orientation and slip sense (faulting mechanism) hardly conform with the regional stress field. The deep focal depth and N-S directional strike-slip motion require transient changes in the medium properties and stress field. Strong ground motions of the midcrustal earthquake induce preferential dynamic stress changes in NE-SW direction, triggering subsequent aftershocks in NE-SW-directional adjacent faults. Both the static and dynamic stress changes caused by the mainshock contribute to the aftershock sequence. The number and focal depths of aftershocks decrease with distance from the mainshock. The different fault-plane orientations between the mainshock and aftershocks suggest earthquake nucleations in independent fault structures. The mainshock occurred in aseismic midcrustal paleovolcanic structure on the outskirt of a high seismicity region. The ML4.9 earthquake suggests possible nucleation of earthquake in seismically-inactive paleotectonic structures, successively incurring aftershocks conforming to the ambient stress. The mainshock and aftershocks suggest that paleotectonic structures may behave as source structures to spawn earthquakes.

Exploring Gender-Based Disparities in Speed, Agility, and Quickness Attributes Among Kho-Kho Players in Mumbai: A Comparative Study

This study aims to investigate the gender-based differences in speed, agility, and quickness (SAQ) attributes among Kho-Kho players in Mumbai, India. Kho-Kho, a traditional Indian sport, requires rapid changes in direction, acceleration, and deceleration, making SAQ crucial for performance. Despite the sport's popularity, there is limited research on gender-specific SAQ characteristics among Kho-Kho players. The study recruited 100 Kho-Kho players (50 males and 50 females) from various clubs and institutions in Mumbai. Participants underwent a series of SAQ tests, including the 40-yard dash, T-test, and Illinois agility test, to assess their speed, agility, and quickness. Results revealed significant gender-based differences in SAQ attributes among Kho-Kho players. Male participants exhibited superior performance in speed-related tests, such as the 40-yard dash, demonstrating faster sprint times compared to females. Conversely, females demonstrated greater agility and quickness in tests like the T-test and Illinois agility test, indicating superior multidirectional movement capabilities. These findings suggest that while male Kho-Kho players excel in straight-line speed, female players possess advantages in agility and quickness, possibly due to differences in biomechanical and physiological factors. Understanding these gender-specific differences can inform training programs tailored to enhance specific SAQ attributes in male and female Kho-Kho players, potentially optimizing their performance and reducing the gender gap in sports. Further research is warranted to explore the underlying mechanisms contributing to these disparities and develop targeted interventions to address them.

Three-dimensional assessment of the maxilla after modified surgically assisted rapid expansion: a retrospective study.

This retrospective study aims to assess the three-dimensional dentoskeletal effects and median palatal suture opening pattern in patients undergoing modified surgically assisted maxillary rapid expansion (SARME) without pterygoid plate detachment. Twenty-eight patients submitted to modified SARME between 2009 and 2016 were retrospectively evaluated through cone-beam computed tomography (CBCT). Dental and skeletal measurements were taken at three different operative periods (before the expansion - T0; at the end of the activation of the Hyrax device - T1; and six months after the immobilization of the device - T2). Statistical analyses, including ANOVA and Pearson's correlation coefficient, were performed using SPSS software. SARME demonstrated significant transverse maxillary expansion (with an average of 6.05mm) with a greater impact in the anterior region. Dental measurements, including canine and molar distances, exhibited significant changes over the operative periods. Bone measurements (ANS and PNS) presented small but significant alterations, including a slight inferior displacement of ANS during device activation. The nasal floor width increased, followed by a width reduction after immobilization. The median palatal suture predominantly exhibited a Type II (V-shaped) opening. The modified SARME presented a transversal direction increase and a super-lower skeletal displacement, with the anterior region being more affected than the posterior region. There was no change in the anteroposterior direction of the maxilla. Additionally, there was an increase in the linear dental measurements and a decrease in the angular measurement, with a positive correlation between the amount of posterior bone expansion and molar expansion as a result of the treatment in the analyzed period.

Unveiling asymmetry impacts of economic policy uncertainty on climate change: fresh insights into African Countries.

This study investigates the influence of economic policy uncertainty on climate change in selected African countries within asymmetric settings. Although previous research has examined the impact of various economic factors on climate change, the asymmetric effects of economic policy uncertainty have not been thoroughly explored, particularly in African countries. We analyze annual data spanning from 1980 to 2017 by utilizing three models: Panel Pooled Mean Group-Autoregressive distributed lag model (ARDL-PMG), Panel Pooled Mean Group-non-linear autoregressive distributed lag model (NARDL-PMG), and Dumitrescu-Hurlin asymmetric causality tests. According to the results of ARDL-PMG estimation, economic policy uncertainty has a detrimental impact on climate change in the long run. However, the NARDL-PMG estimation suggests that a positive shock in economic policy uncertainty negatively affects long-term climate change mitigation. However, a negative shock has a beneficial effect on climate change in the long term. In African nations, positive and negative changes in economic policy uncertainty failed to generate any significant climate change effects in the short run. The results also reveal that both positive and negative shocks in economic policy may cause climate change in a one-way direction. Based on the findings of our study, we recommend that African policymakers implement programs aimed at reducing economic policy uncertainties to help mitigate the effects of climate change.