Significant Asymmetry Research Articles

1316 Chronic Epidural Hematoma: A Systematic Review and Meta-Analysis

Abstract Background Epidural hematoma constitutes a common condition in neuro-traumatology. If its acute form is well known, the chronic one remains less described. In this study, we aimed to evaluate the epidemiology, presentations, management, and outcomes of chronic epidural hematoma (CEDH). Method Systematic searches of PubMed, Google Scholar, and ScienceDirect were performed from a database searching for all studies reporting CEDH. Pooled statistics were calculated using measures of central tendency and spread. Results Totally, 3009 studies were identified, of which 95 were included with 359 patients. CEDH was more common in intracranial than spinal (91.9% vs 8.1%). The average age of onset was 37.2 +/- 4.83 years. The common cause found was trauma (n = 279; 77,72%) with 271 (97.1%) cases for the head and 8 (2,9%) cases for the spine. The median delay between the trauma and the first symptoms was 13.31 +/- 3.43 days in intracranial level and 16.37 +/- 5.87 days in spinal level. CT-scan constituted the main diagnosis tool. The lesion was predominantly located in the temporal region at the intracranial level and lumbar region at the spinal level. Craniotomy and laminectomy constituted the most reported treatment option respectively at the intracranial and spinal level. The outcome was commonly uneventful. Correlation and Regression test for publication bias assessment show no significant Funnel plot asymmetry with high p-value (p = 0.8458 and p = 0.9596, respectively). Conclusions There was no clear risk factor found for CEDH. The treatment was mostly surgical.

Three-dimensional assessment of facial asymmetry in class III subjects, part 2: evaluating asymmetry index and asymmetry scores.

To evaluate the outcomes of corrective surgical treatment for craniofacial asymmetry using four different methods with the aim of developing the best technique for craniofacial asymmetry assessment. CBCT images of twenty-one class III subjects with surgically corrected craniofacial asymmetry and twenty-one matched controls were analyzed. Twenty-seven hard tissue landmarks were used to quantify asymmetry using the following methodologies: the asymmetry index (AI), asymmetry scores based on the clinically derived midline (CM), Procrustes analysis (PA), and modified Procrustes analysis (MPA). Modified Procrustes analysis successfully identified pre-operative asymmetry and revealed severe asymmetry at the mandibular regions compared to controls, which was comparable to the asymmetry index and clinically derived midline methods, while Procrustes analysis masked the asymmetric characteristics. Likewise, when comparing the post-surgical outcomes, modified Procrustes analysis not only efficiently determined the changes evidencing decrease in facial asymmetry but also revealed significant residual asymmetry in the mandible, which was congruent with the asymmetry index and clinically derived midline methods but contradictory to the results shown by Procrustes analysis. In terms of quantifying cranio-facial asymmetry, modified Procrustes analysis has evidenced to produce promising results that were comparable to the asymmetry index and the clinically derived midline, making it a more viable option for craniofacial asymmetry assessment. Modified Procrustes analysis is proficient in evaluating cranio-facial asymmetry with more valid clinical representation and has potential applications in assessing asymmetry in a wide spectrum of patients, including syndromic patients.

Advanced Biomaterials and Topical Medications for Treating Diabetic Foot Ulcers: A Systematic Review and Network Meta-Analysis.

Significance: With the increasing diabetic population worldwide, diabetic foot ulcers (DFUs) are a significant concern. This study aimed to compare the efficacy of skin substitutes, biomaterials, and topical agents with standard care. Recent Advances: A meta-analysis was conducted using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. PubMed, EMBASE, and Web of Science were searched using the following keywords: diabetes mellitus AND skin graft OR tissue replacement OR dressing OR drug. Two independent reviewers performed data collection and quality assessment of the eligible studies. The primary outcome was the 12- to 16-week healing rates and the secondary outcome was recurrence rates. Critical Issues: Thirty-eight randomized controlled trials, including 3,862 patients, were analyzed. The studies exhibited low heterogeneity (τ2 = 0.10) without significant asymmetry (Egger's test, p = 0.8852). After pooling direct and indirect estimates, placenta-based tissue products exhibited the best wound healing probability (p-score = 0.90), followed by skin substitutes with living cells (p-score = 0.70), acellular skin substitutes (p-score = 0.56), and advanced topical dressings (p-score = 0.34) compared with standard of care. The recurrence analysis showed significant improvement in the intervention group compared with the control group (11.21% vs. 15.15%). Future Directions: This network meta-analysis provides the relative effectiveness and rank of biomaterials and topical dressings in DFU healing. The results could help clinical decision making.

CP asymmetry from the resonance effect of the B meson decay process with π and K final states* *Supported by the Natural Science Foundation of Henan Province, China (232300420115), and the National Natural Science Foundation of China (12275024).

We present the novel resonance, which generates a strong phase associated with vector meson resonances, leading to significant CP asymmetry in the interference region. The , , and resonances arise from the mixing of the vector mesons ϕ, ρ, and ω. We calculate the CP asymmetry from the decay mode of . Meanwhile, the localized CP asymmetries are presented and a detailed analysis is performed. The CP asymmetry from the decay mode of is also presented in our framework, which is highly consisted with that of the LHC experiment. The introduced CP asymmetry can provide a favorable theoretical support for experimental exploration in the future.

Plastic deformation of single crystals of the equiatomic Cr-Fe-Co-Ni medium entropy alloy – A comparison with Cr-Mn-Fe-Co-Ni and Cr-Co-Ni alloys

The plastic deformation behavior of single crystals of the equiatomic Cr-Fe-Co-Ni medium-entropy alloy was investigated in compression and tension from 9 K to 1373 K. The critical resolved shear stress (CRSS) for {111}<11¯0> slip is 44–45 MPa at room temperature and does not exhibit significant tension-compression asymmetry. It increases rapidly with decreasing temperature but exhibits a dulling of the temperature dependence below 77 K due to the inertia effect. The 0 K CRSS was determined to be 200 MPa by extrapolating the temperature dependence of CRSS from above 77 K to lower temperatures. This CRSS value is higher than that of the equiatomic Cr-Mn-Fe-Co-Ni high-entropy alloy, 174 MPa, but lower than that of the equiatomic Cr-Co-Ni medium-entropy alloy, 225 MPa. The rank of CRSS at 0 K of the three equiatomic alloys is consistent with the prediction of some solid solution strengthening models. The stacking fault energy (SFE) of the Cr-Fe-Co-Ni is about 20 mJ/m2, which falls between those of the Cr-Mn-Fe-Co-Ni and Cr-Co-Ni alloys. Deformation twinning in the Cr-Fe-Co-Ni MEA occurs at a shear stress of 249 MPa on conjugate (1¯1¯1) planes in the form of Lüders deformation at 77 K. The relationship between twinning stress and SFE is not monotonic as previously believed, but displays a concave with a minimum twinning stress at an intermediate SFE value.

Active-feedback quantum control of an integrated low-frequency mechanical resonator

Preparing a massive mechanical resonator in a state with quantum limited motional energy provides a promising platform for studying fundamental physics with macroscopic systems and allows to realize a variety of applications, including precise sensing. While several demonstrations of such ground-state cooled systems have been achieved, in particular in sideband-resolved cavity optomechanics, for many systems overcoming the heating from the thermal bath remains a major challenge. In contrast, optomechanical systems in the sideband-unresolved limit are much easier to realize due to the relaxed requirements on their optical properties, and the possibility to use a feedback control schemes to reduce the motional energy. The achievable thermal occupation is ultimately limited by the correlation between the measurement precision and the back-action from the measurement. Here, we demonstrate measurement-based feedback cooling on a fully integrated optomechanical device fabricated using a pick-and-place method, operating in the deep sideband-unresolved limit. With the large optomechanical interaction and a low thermal decoherence rate, we achieve a minimal average phonon occupation of 0.76 when pre-cooled with liquid helium and 3.5 with liquid nitrogen. Significant sideband asymmetry for both bath temperatures verifies the quantum character of the mechanical motion. Our method and device are ideally suited for sensing applications directly operating at the quantum limit, greatly simplifying the operation of an optomechanical system in this regime.

Excited Hydroxyl Outflow in the High-mass Star-forming Region G34.26 + 0.15

G34.26 + 0.15 is a region of high-mass star formation that contains a broad range of young stellar objects in different stages of evolution, including a hot molecular core, hypercompact H ii regions, and a prototypical cometary ultracompact H ii region. Previous high-sensitivity single-dish observations by our group resulted in the detection of broad 6035 MHz OH absorption in this region; the line showed a significant blueshifted asymmetry indicative of molecular gas expansion. We present high-sensitivity Karl G. Jansky Very Large Array (VLA) observations of the 6035 MHz OH line conducted to image the absorption and investigate its origin with respect to the different star formation sites in the region. In addition, we report detection of 6030 MHz OH absorption with the VLA and further observations of 4.7 GHz and 6.0 GHz OH lines obtained with the Arecibo Telescope. The 6030 MHz OH line shows a very similar absorption profile as the 6035 MHz OH line. We found that the 6035 MHz OH line absorption region is spatially unresolved at ∼2″ scales, and it is coincident with one of the bright ionized cores of the cometary H ii region that shows broad radio recombination line emission. We discuss a scenario where the OH absorption is tracing the remnants of a pole-on molecular outflow that is being ionized inside-out by the ultracompact H ii region.

Asymmetry in body composition parameters of the upper and lower extremity among healthy Austrian women.

Humans typically have bilateral symmetry, however, deviations from perfect symmetry can be observed. In the case of the upper extremities, mostly a right-biased asymmetry in the length or strength of the bones, but also lean body mass was reported. Regarding the lower extremities, the asymmetry patterns are weaker. The aim of this study is to analyze directional and cross-asymmetry in body composition parameters among healthy non-athletic women. In particular, it is hypothesized that body composition asymmetry patterns of the limbs change with increasing age. 584 Austrian women aged between 16 and 83 years were enrolled in the study. Data collection took place between 1995 and 2000 at the Menox outpatient department for the treatment of climacteric symptoms in Vienna. Bone mineral density (BMD), bone mineral content (BMC), lean mass, and fat mass was determined using dual-energy-x-ray absorptiometry (DEXA). Signed asymmetry was calculated for each body composition parameter of the upper and lower limbs. Right-sided symmetry dominated for lean mass, BMC, and BMD in the upper extremity. Asymmetry in the lower limbs was not as strong as in the arms, but a right-sided asymmetry was still observable. Fat mass showed the strong right-sided asymmetry of all measurements for the lower extremities in the whole sample. Contra lateral asymmetry of the extremities could be found in 37-45% of the sample for lean mass, BMD, and BMC. For fat mass, almost half of the sample displayed cross asymmetry. Significant associations between asymmetry patterns and age were observable for the fat mass of the upper extremities only. Participants younger than 30 years showed a significant left-sided asymmetry for fat mass in the upper extremities. However, this pattern changed around the age of 30 and shifted to a slight right-sided asymmetry. In general, the body composition of the upper and lower limbs showed distinct asymmetry patterns.

Asymmetric Ionospheric Fluctuations Over the Circum‐Pacific Regions Following the January 2022 Tonga Volcanic Eruption

AbstractThe Hunga Tonga‐Hunga Ha'apai volcanic eruption on 15 January 2022 had a significant impact on the ionosphere‐thermosphere system, resulting in large‐scale ionospheric irregularities with longitudinal and latitudinal asymmetries. Multiple instruments recorded these irregularities, indicating the propagation of a westward wave at an average velocity of 354 ± 8 m/s, which led to plasma irregularities of 0.2 TECu/min. Conversely, an eastward‐propagating wave was detected on the Pacific's east coast, traveling at a speed of 348 ± 6 m/s, with a corresponding decrease in plasma fluctuations to 0.1 TECu/min. In Asia, noticeable plasma irregularities appeared within a few hours after the eruption, and the maximum speed exceeded 1,100 m/s, which cannot be explained by the acoustic wave model. There was also a significant latitudinal asymmetry of ionospheric disturbances in the Asian‐Oceania sector, with the plasma density around Oceania depleted by 2–3 orders of magnitude within the altitudes of ∼150–575 km, while the ion density over Asia was enhanced by 1–2 orders of magnitude, and was uplifted ∼50 km. The plasma temperature was proportional to ion density, indicating the ion temperature reduced ∼500 K and increased 100–200 K around Oceania and Asia, respectively. The equatorial electric field, vertical E × B drifts and thermospheric O/N2 density ratio also fluctuated significantly following the eruption, indicating the redistribution of charged particles due to the magnetic field mapping effect, which was the main contributor to the asymmetries observed.

Comparing kinematic asymmetry and lateral step-down test scores in healthy, chronic ankle instability, and patellofemoral pain syndrome female basketball players: a cross-sectional study

We aimed to understand whether ankle dorsiflexion range of motion (ROM) and dynamic knee valgus (DKV) kinematic inter-limb asymmetries would be associated with the Lateral Step-Down Test (LSD) in basketball players with chronic ankle instability (CAI), patellofemoral pain (PFP) and healthy controls (HC). An observational cross-sectional study with a between-subject design was employed. Female basketball athletes with CAI (n = 20), PFP (n = 20) and HC (n = 20) were recruited. Ankle dorsiflexion-ROM, DKV angle during a single-limb squat, and LSD quality were measured bilaterally. The Asymmetry index (ASI) was calculated to identify between-limb percentage imbalances. The correlation matrix between the tasks was calculated. Ankle dorsiflexion-ROM was less in the CAI and PFP than in the HC group regardless of limb (p < 0.001). DKV angle was greater in the CAI and PFP than in the HC group bilaterally (p < 0.001). LSDs were similar between the PFP and CAI groups (p = 0.698) but worse than the HC group (p = 0.001). The ASI showed asymmetry across all tasks (p < 0.001), with the greatest asymmetry for the DKV angle. The correlation matrix between tasks on both limbs was significant (p < 0.05). Our findings suggest significant asymmetries in ankle dorsiflexion-ROM and frontal plane knee control are present in female basketball athletes with CAI and PFP, and thus, highlights need to evaluate and reduce limb asymmetries in these populations.

18F]-FDopa positron emission tomography imaging in corticobasal syndrome.

First, to investigate the patterns of [18F]-FDOPA positron emission tomography imaging in corticobasal syndrome using visual and semi-quantitative analysis and to compare them with patterns found in Parkinson's disease and progressive supranuclear palsy. Then, to search for correlations with clinical features and [18F]-FDG positron emission tomography imaging. 27 corticobasal syndrome patients who underwent [18F]-FDOPA positron emission tomography imaging were retrospectively studied. They were compared to 27 matched Parkinson's disease patients, 12 progressive supranuclear palsy patients and 53 normal controls. Scans were visually assigned to one of the following patterns: normal; unilateral homogeneous striatal uptake reduction; putamen uptake reduction with putamen-caudate gradient. A semi-quantitative analysis of striatal regional uptake and asymmetry was performed and correlated to clinical features and [18F]-FDG positron emission tomography patterns. [18F]-FDOPA positron emission tomography appeared visually abnormal in only 33.5% of corticobasal syndrome patients. However, semi-quantitative analysis found putaminal asymmetry in 63%. Striatal uptake was homogeneously reduced in both putamen and caudate nucleus in corticobasal syndrome patients unlike in Parkinson's disease and progressive supranuclear palsy. No correlation was found between [18F]-FDOPA positron emission tomography and clinical features. Half of corticobasal syndrome patients presented a corticobasal degeneration pattern on [18F]-FDG positron emission tomography. CONCLUSION: [18F]-FDOPA positron emission tomography can often be normal in corticobasal syndrome patients. Semi-quantitative analysis is useful to unmask a significant asymmetry in many of them. Homogeneous striatal uptake reduction contralateral to the clinical signs is highly suggestive of corticobasal syndrome. This finding can be helpful to better characterize this syndrome with respect to Parkinson's disease and progressive supranuclear palsy.

Asymmetric and time-frequency volatility connectedness between China and international crude oil markets with portfolio implications

This paper tries to examine asymmetric and time-frequency volatility connectedness between the Chinese crude oil futures market and international oil benchmarks. To this end, we separate the realized volatility as bad or good volatility and decompose the aggregate volatility connectedness among these oil markets into the short-, medium-, and long-term components. Our results first show that these crude oil markets are highly connected, whereas the Chinese crude oil futures market is a net receiver in the volatility system. Second, the spillover effect caused by bad volatility is significantly different from that of good volatility, revealing significant asymmetry in the volatility spillovers. Third, the volatility spillovers in the short-term frequency band account for the most of total volatility spillovers. Finally, our results prove that the volatility connectedness information among different oil markets helps design trading strategies and shed light on the arbitrage opportunities in the Chinese new crude oil futures market.

SPATIAL DIFFERENTIATION OF COMMODITY TRADE BETWEEN UKRAINE AND THE EU

At the current stage of the socio-economic development of Ukraine in the conditions of Russian aggression, the topical issue is the expansion of foreign economic relations with EU member countries. The purpose of the study is a spatial analysis of the features of regional differentiation of Ukraine’s commodity trade with the countries of the European Union in the context of expanding trade and economic relations after signing the Agreement on a free trade zone with the EU and granting Ukraine the status of a candidate for EU membership. Such research methods as structural and spatial analysis, statistical and correlation analysis, and typological analysis were used. The dynamics of commodity trade between Ukraine and the EU in 2001–2021 are analyzed and the main trends in interstate trade in goods were identified. It has been revealed that the general trend of bilateral trade relations with the countries of the European Union in the 21st century is generally similar to the trend of the turnover of foreign commodity trade between Ukraine and all countries of the world. It has been established that the spatial differentiation of Ukraine’s commodity trade with the EU clearly shows great variability and asymmetry of export and import indicators. The dependence between the level of economic development of Ukraine’s regions and the commodity trade volume with EU countries is traced. A characteristic feature is the spatial heterogeneity of the distribution of commodity trade in Ukraine’s regions according to the predominant directions of foreign commodity trade relations. The western regions of Ukraine have the highest level of connectivity of commodity trade with the countries of the European Union, which is explained by better transport accessibility to EU markets and the development of cross-border cooperation. According to the main directions of trade flows and on the basis of a comparison of the connectivity and balance coefficients of commodity trade with EU countries, six types of Ukraine’s regions are identified. The novelty of the research is the identification of the features of regional differentiation and significant asymmetry in the commodity trade of Ukraine’s regions with the countries of the European Union based on the criterion of connectivity and symmetry of trade flows using spatial analysis.

Hemispheric symmetry and asymmetry of poleward moving radar auroral forms (PMRAFs) and associated polar cap patches during a geomagnetic storm

Introduction: Magnetopause reconnection is known to impact the dayside ionosphere by driving fast ionospheric flows, auroral transients, and high-density plasma structures named polar cap patches. However, most of the observed reconnection impact is limited to one hemisphere, and a question arises as to how symmetric the impact is between hemispheres.Methods: We address the question using interhemispheric observations of poleward moving radar auroral forms (PMRAFs), which are a “fossil” signature of magnetopause reconnection, during a geomagnetic storm. We are particularly interested in the temporal repetition and spatial structure of PMRAFs, which are directly affected by the temporal and spatial variation of magnetopause reconnection. PMRAFs are detected and traced using SuperDARN complemented by DMSP, Swarm, and GPS TEC measurements.Results: The results show that PMRAFs occurred repetitively on time scales of about 10 min. They were one-to-one related to pulsed ionospheric flows, and were collocated with polar cap patches embedded in a Tongue of Ionization. The temporal repetition of PMRAFs exhibited a remarkably high degree of correlation between hemispheres, indicating that PMRAFs were produced at a similar rate, or even in close synchronization, in the two hemispheres. However, the spatial structure exhibited significant hemispherical asymmetry. In the Northern Hemisphere, PMRAFs/patches had a dawn-dusk elongated cigar shape that extended &amp;gt;1,000 km, at times reaching &amp;gt;2,000 km, whereas in the Southern Hemisphere, PMRAFs/patches were 2–3 times shorter.Conclusion: The interesting symmetry and asymmetry of PMRAFs suggests that both magnetopause reconnection and local ionospheric conditions play important roles in determining the degree of symmetry of PMRAFs/patches.

Investigating the link between frontal sinus morphology and craniofacial characteristics with sex: A 3D CBCT study on the South Indian population

Background: Measurement of craniofacial parameters plays an important role in sex determination in forensic science. The present study was done using cone beam computed tomography (CBCT) scans to evaluate the morphologic structure of the frontal sinuses and compare it with the width of nasal, cranial, maxillary and mandibular width which might help us in sex determination. Methods: A cross-sectional retrospective study was conducted using 142 full field of view (FOV) scans of patients archived from the department. The width of the nose, cranium, maxilla, and mandibular width was measured and compared with the frontal sinus between the two sexes. Results: A paired t-test was done to compare the linear measurements for both sexes' right and left frontal sinuses. The measurements were higher in males when compared to females. There was a statistically significant asymmetry (larger dimension on the left side) of the anterioposterior (p-value of 0.012) and superior-inferior dimensions in males (p-value of 0.135). Spearman's correlation showed that frontal sinus correlated with other craniofacial parameters like nasal, cranial, maxillary and mandibular width among both sexes. The frontal sinus, nasal, cranial, maxillary and mandibular widths were higher in males when compared to females (independent t-test). Discriminant function scores showed 66-68% accuracy to discriminate sex, using the anteroposterior dimension and mandibular width. Conclusions: The measurement of craniofacial parameters using CBCT can aid in determining the sex of unidentified and decomposed bodies.

Analysis of frequency chirping on the electron bunch acceleration during Laguerre–Gauss laser interaction

We intend to examine the impact of frequency chirping on the efficient vacuum acceleration of an electron bunch using a chirped Laguerre–Gauss (LG) laser pulse. The study demonstrates that achieving high-energy electron acceleration relies not only on significant pulse asymmetry but also on ensuring phase synchronization in the LG laser interaction. The findings highlight the feasibility of generating outgoing electron bunches with high energy and low divergence through the selection of an optimal chirping value. Furthermore, we establish that chirping the LG laser pulse facilitates the acceleration of electrons to high energy using a lower laser intensity compared to the scenario without chirping.

Drivers of WACR-Repo Rate Spread: An Empirical Analysis of India

The spread between the policy rate and operating target rate of the Reserve Bank of India (RBI) has consequences on the transmission of monetary policy signals. Using weekly data from 2011 to 2020 (504 observations), the study employs variants of General Auto Regressive Conditional Heteroskedastic model to comprehensively analyse the factors that drive this spread. Besides the factors retrieved from the literature, this study also gauges the impact of COVID-19 on the spread and its volatility. The results indicate that the spread is significantly impacted by its lag, volume of transactions in the counterpart markets, distribution pattern of the liquidity by the central bank, foreign market intervention, liquidity adjustment facility (LAF), currency in circulation and reserve requirement while market expectations and government cash balances are found to be non-significant. Besides, announcement effect of COVID and changes in key rates are found to be significant. The results of Exponential GARCH do not find significant asymmetry in response to positive and negative shocks on the spread. Volatility in the spread is comparatively more responsive to its lags than to the market shocks.

Unilateral Cleft Lip and Palate Has Asymmetry of Bony Orbits: A Retrospective Study.

Facial asymmetry is common in unilateral clefts. Since virtual surgical planning (VSP) is becoming more common and automated segmentation is utilized more often, the position and asymmetry of the orbits can affect the design outcome. The aim of this study is to evaluate whether non-syndromic unilateral cleft lip and palate (UCLP) patients requiring orthognathic surgery have asymmetry of the bony orbits. Retrospectively, we analyzed the preoperative cone-beam computed tomography (CBCT) or computed tomography (CT) data of UCLP (n = 15) patients scheduled for a Le Fort 1 (n = 10) or bimaxillary osteotomy (n = 5) with VSP at the Cleft Palate and Craniofacial Center, Helsinki University Hospital. The width, height, and depth of the bony orbit and the distance between the sella turcica and infraorbital canal were measured. A volumetric analysis of the orbits was also performed. The measurements were tested for distribution, and the cleft side and the contralateral side were compared statistically with a two-sided paired t-test. To assess asymmetry in the non-cleft population, we performed the same measurements of skeletal class III patients undergoing orthognathic surgery at Päijät-Häme Central Hospital (n = 16). The volume of bony orbit was statistically significantly smaller (p = 0.014), the distance from the infraorbital canal to sella turcica was shorter (p = 0.019), and the anatomical location of the orbit was more medio-posterior on the cleft side than on the contralateral side. The non-cleft group showed no statistically significant asymmetry in any measurements. According to these preliminary results, UCLP patients undergoing orthognathic surgery show asymmetry of the bony orbit not seen in skeletal class III patients without a cleft. This should be considered in VSP for the correction of maxillary hypoplasia and facial asymmetry in patients with UCLP.

Study of the relationship between onset lateralization and hemispheric white matter asymmetry in Parkinson's disease.

Parkinson's disease (PD) is characterized by a lateralized onset, but its cause and mechanism are still unclear. Obtaining diffusion tensor imaging (DTI) data from the Parkinson's Progression Markers Initiative (PPMI). Tract-based spatial statistics analysis and region-of-interest-based analysis were performed to evaluate the white matter (WM) asymmetry using original DTI parameters, Z Score normalized parameters, or the asymmetry index (AI). Hierarchical cluster analysis and least absolute shrinkage and selection operator regression were performed to construct predictive models for predicting the PD onset side. DTI data from The Second Affiliated Hospital of Chongqing Medical University were obtained for external validation of the prediction model. 118 PD patients and 69 healthy controls (HC) from PPMI were included. Right-onset PD patients presented more asymmetric areas than left-onset PD patients. The inferior cerebellar peduncle (ICP), superior cerebellar peduncle (SCP), external capsule (EC), cingulate gyrus (CG), superior fronto-occipital fasciculus (SFO), uncinate fasciculus (UNC), and tapetum (TAP) showed significant asymmetry inleft-onset and right-onset PD patients. An onset-side-specific pattern of WM alterations exists in PD patients, and a prediction model was constructed. The predicting models based on AI and ΔZ Score presented favorable efficacy in predicting PD onset side by external validation in 26 PD patients and 16 HCs from our hospital. Right-onset PD patients may have more severe WM damage than left-onset PD patients. WM asymmetry in ICP, SCP, EC, CG, SFO, UNC, and TAP may predict PD onset side. Imbalances in the WM network may underlie the mechanism of lateralized onset in PD.

Effects of Multi-Directional Seismic Input on Non-Linear Static Analysis of Existing Reinforced Concrete Structures

Recent studies have shown the importance of including the seismic input directionality in nonlinear analyses for an accurate prediction of the structural demand on frame structures. This paper proposes a new method that includes the multi-directionality of the input seismic forces in Nonlinear Static Analyses (NSAs). Conventionally, the pushover (PO) analyses apply monotonically increasing lateral loads in two directions that typically correspond with the building X and Y directions, that in the case of a rectangular plan are parallel to the building sides. Since in general the direction of the seismic input is a priori unknown, the effects of applying the PO load patterns along varying angles are studied in this paper. Two non-code-conforming reinforced concrete buildings are used as a case study. They have identical structural design but the first one is doubly symmetric while the second one has a significant plan asymmetry due to the translation of the center of mass. PO loads are applied to both structures at angles between 0° and 360° with 15° increments. The results of the NSAs are compared with those of multi-directional NHAs applied at the same angles. The structural demands show that the multi-directional NSAs are more conservative than the conventional NSAs, especially at the corners of the asymmetric- plan building where they can yield significantly higher demands. The base shear capacities in the X and Y directions decrease for intermediate angles due to the interaction between the responses in the X and Y directions that can be captured thanks to the columns’ fiber section discretization. On average the results of the multi-directional NSAs are closer to those of the NHAs, even though they are generally lower.