Areas Of High Intensity Research Articles

Evaluation of rocking seismic isolation performance of railway tall piers with different energy dissipation devices

Conventional pier top isolation measures cannot reduce the inertial force produced by railway gravity tall piers. This may damage the pier column and pile foundation during strong earthquakes. As an effective pier bottom seismic isolation structure, rocking piers have broad application prospects in railway tall pier bridges. This paper considers five energy dissipation devices (EDDs) to constrain the bottom of a free rocking pier (F-RP), namely buckling restrained braces (BRBs), yielding steel cables (YSCs), self-centering buckling restrained braces (SC-BRBs), superelastic shape memory alloy wires (SMAs), and viscous dampers (VDs). In particular, an additional “locking” structure is proposed to prevent excessive rocking of the piers and protect the EDDs. Parameter design methods are proposed for damage control and residual deformation control of piers. Nonlinear static and dynamic analyses are performed. The results show that the fixed base piers based on the ductility design suffered severe damage during strong earthquakes. The longitudinal rebar strain ratio is recommended as the damage index for the rocking pier due to large axial force fluctuations. Based on the design method proposed in this paper, the additional EDD constraints make the pier's expected damage level controllable and improve the post-earthquake predictability of the railway pier. BRBs and VDs are unfavorable to pier bottom shear forces. YSCs may produce irrecoverable residual deformation, while BRBs may have significant residual stresses. SC-BRBs and SMAs require no post-earthquake repair. SC-BRBs have more potential for application in rocking piers in high-intensity earthquake areas.

Analysis of the cancer occurrence related to natural radioactivity in the Rio Grande do Norte State, Brazil.

The state of Rio Grande do Norte, located in the Northeast region of Brazil, has areas of granites and pegmatites with minerals that have varying concentrations of uranium. Consequently, high concentrations of radon gas, a carcinogenic substance for humans, can occur. The present study aimed to assess the occurrence of cancer and its association with exposure to sources of natural radioactivity using geological and geophysical information in the aforementioned state. The spatial dependence of pulmonary, breast, stomach, leukemia, and skin cancer cases with the location of radioisotope sources were analyzed using geoprocessing tools. The geoprocessing analysis showed a differential pattern of uranium emission throughout the state, with the highest emission from areas with pegmatites outcrops. A spatial dependency of cancer cases was shown (Moran index: 0.43; p < 0.01). Moreover, a higher rate of natural radioactivity-cancer cases was associated with the high-intensity natural radioactivity areas: odds ratio:1.21 (95% CI 1.20; 1.23), following the same pattern when separately compared the different related types of cancer. These results highlight the importance of natural radioactivity as a public health problem in the Brazilian environmental scenario, confirming the need for further studies as the first toward understanding and implementing health management strategies mitigating the exposures, especially in areas of environmental risk.

Brain Magnetic Resonance Imaging (MRI) in Spinal Muscular Atrophy: A Scoping Review.

5q Spinal Muscular Atrophy (SMA) is a prototypical lower motor neuron disorder. However, the characteristic early motor impairment raises the question on the scope of brain involvement with implications for further investigations on the brain as a potential therapeutic target. To review changes across the SMA clinical spectrum reported on brain magnetic resonance imaging (MRI). We conducted a scoping review of existing literature on PubMed and EMBASE. Two reviewers searched and retrieved relevant articles on magnetic resonance brain imaging in individuals with SMA censoring to April 2022. Full-text articles published in peer-reviewed journals or abstracts accepted to conferences in English and French were included. Twelve articles were identified describing a total of 39 patients [age range: 11 days to 41 years old, type 0 (n = 5), type 1 (n = 4), type 2 (n = 2), type 3 (n = 22), type 4 (n = 6)]. All reported structural changes and did not explore other MRI modalities. In individuals with infantile onset SMA, cortical and subcortical brain abnormalities in white matter, basal ganglia, thalamus, hippocampus, and high intensity areas around lateral ventricles and thalami were reported over time. In individuals with later-onset SMA, reduced cerebellar and lobular volume were observed as well as increased grey matter density in motor areas. Limited data on brain imaging in SMA highlights both cortical and subcortical involvement in SMA, supporting the hypothesis that changes are not restricted to lower motor neuron pathways. Further studies are needed to determine the extent and prevalence of structural and functional brain changes across SMA types.

Spatial and temporal distribution of HCHO and its pollution sources based on satellite remote sensing: a case study of the Yangtze River Economic Belt

Abstract In recent years, with the acceleration of industrialization and the expansion of urban scale, air pollution including formaldehyde (HCHO) becomes more and more serious. In order to study HCHO pollution in the Yangtze River Economic Belt (YEB), the temporal and spatial evolution of atmospheric HCHO and its influencing factors were analyzed by using the Ozone Monitoring Instrument (OMI) during 2012–2021. The results showed that the concentration of YEB HCHO column was unevenly distributed, with high values concentrated in Anhui, Jiangsu, Yunnan and Hubei provinces. During the past 10 years, the concentration of YEB HCHO column varied between 10.28 and 17.19 × 1015 molec cm−2, and the lowest concentration of HCHO column was 13.16 × 1015 molec cm−2 in 2015. However, it reached the peak value in 2018 (14.93 × 1015 molec cm−2). In natural sources, normalized vegetation index (NDVI) and leaf area index (LAI) had greater influence on YEB HCHO, and the correlation was −0.91 ∼ 0.97 and −0.9 ∼ 0.95, respectively. The positive correlation area between HCHO and Mean annual temperature (MAT) reached 93%. The contribution of high-intensity human activity areas to HCHO cannot be underestimated. Industrial and civil sources have great influence on HCHO. In addition, the potential source of HCHO in Shanghai is affected by local emission sources, trans-regional potential sources, northwest air mass and ocean airflow.

Effect of urbanization on gust wind speed in summer over an urban area in Eastern China

Previous studies have extensively examined effects of urbanization on mean wind speed, but few studies were aimed at gust wind speed, while large wind gust could cause safety and economic hazard to a variety of activities. In this study, the effect of urbanization on the gust wind speed in Nanjing, China is assessed using the Weather Research and Forecasting (WRF) model with a parameterization of the gust wind speed. The WRF simulations are run for the summer period of 2013 with the underlying surface before and after the urbanization. The results indicate that although the mean wind speed is reduced, the gust wind speed in the urban areas is increased significantly due to the enhanced friction velocity and less atmospheric stability induced by the urbanization, while the contribution of deep convection is relatively small. The gust wind speed increases more in the nighttime (0.6–0.9 m s−1) than in the daytime (less than 0.3 m s−1), since the turbulence is enhanced more in the nighttime than in the daytime after the urbanization. The probability distribution shows that the increase of gust wind speed is mainly between 0.0–0.5 m s−1 in the urban areas. In different urban land categories, the increase of the gust wind speed is larger in the commercial or industrial areas than in high-intensity and low-intensity residential urban areas. Averagely, the gust wind speed in the entire city after the urbanization increases by 0.02, 0.36 and 0.19 m s−1 for the daytime, nighttime and daily mean, respectively.

Shaking table test of fully assembled precast concrete shear wall substructure with tooth groove connection and vertical reinforcement lapping in reserved hole

In this paper, an innovative fully assembled precast concrete shear wall structural system with tooth groove connection and vertical reinforcement lapping in reserved hole was proposed, and the constructional requirements and joint assembly process were elaborated in detail. Based on the similarity theory, a 1/2 scaled fully assembled precast shear wall substructure was designed and manufactured. The damage mode, dynamic characteristics, acceleration response, displacement response, seismic action response, inter-storey shear response and strain response of the fully assembled precast concrete shear wall substructure with tooth groove connection and vertical reinforcement lapping in reserved hole under the different earthquake excitations were comprehensively analyzed by shaking table test, and the connection performance and seismic performance of the substructure in high intensity areas were investigated. The research results showed that the cracks at the horizontal joint of the 1st floor were completely penetrated, accompanied by slight concrete spalling, the 1st floor shear wall perpendicular to the input direction of seismic excitation was slightly uplifted, and there was no obvious damage in other parts. Overall, the tooth groove connection and vertical reinforcement lapping in reserved hole was reliable. Besides, the dynamic characteristics and seismic response of the substructure were consistent with the three-stage test phenomena. The acceleration amplification factor, storey displacement, seismic action increased with the increase of the height of the substructure and the excitation of PGA. When the excitation of PGA = 0.638 g, the maximum inter-storey drift was 1/213, which was in line with the plastic limit of 1/120. On the whole, the integrity of the substructure remained good and there was no danger of collapse. Finally, a comprehensive seismic performance evaluation method suitable for fully assembled precast concrete shear wall substructure with tooth groove connection and vertical reinforcement lapping in reserved hole was proposed with inter-storey drift and damage index as quantitative indicators.

Seismic Active Earth Pressure of Infinite Width Backfilled Soil on Cantilever Retaining Wall with Long Relief Shelf under Translational Mode

In the area of high seismic intensity, there were few methods for calculating active earth pressure (Ea). Especially for the cantilever retaining wall with long relief shelf (CRW-LRS), the theoretical method lags behind the practical engineering. The seismic active earth pressure (ES) of the CRW-LRS subject to translational mode was researched. By finite element method (FEM), the failure mode of the active limit state under seismic load was evaluated. The results show that the backfill behind the wall generates the first sliding surface at the wall heel bottom, the second at the wall heel top, and the third at the relief shelf top. The calculation formula of ES under long relief shelf failure mode was proposed using the limit analysis method of a horizontal differential layer. The calculation results were compared with the FEM results to prove the rationality and reliability of the theoretical solution. The effects of relief shelf relative length (l) and position (m), wall heel length (n), internal frictional angle of the backfill (ϕ), seismic horizontal acceleration (ah), and seismic vertical acceleration (aV) on ES were studied.

Identification of bird conservation gaps of protected areas in high-intensity development area: A case study of Tianjin, China.

Due to the long-term disturbance of human activities, natural habitats in the high-intensity development areas have been seriously degraded, causing serious threat to local biodiversity. The conservation efficiency of natural reserves in these regions needs to be improved urgently. Scientific evaluation of conservation efficiency of nature reserves and identification of biodiversity conservation hotspots and conservation gaps in high-intensity development areas are of great significance to sustainable development of urbanization. With birds as the indicator group for biodiversity, we used MaxEnt and InVEST models to calculate the hot spots of bird diversity and habitat quality, and compared with current boundaries of protected areas in Tianjin to accurately identify the conservation gaps. The results showed that 228 bird species belonging to 54 families and 19 orders were recorded. All kinds of natural and artificial wetlands in the coastal area were the most suitable habitats for birds, accounting for 66.8% of bird diversity hotspots in Tianjin, and the artificial wetlands of reservoirs and fish ponds had high suitability as bird habitats due to sufficient food sources, which indicated that moderate anthropogenic interference would improve species diversity. The coverage rate of protected areas for bird diversity hotspots was only 37.7% in Tianjin, which indicated a serious conservation gap. The gaps mainly included wetlands in Dashentang and Lin'gang areas, the river junction and the estuary wetland, which should be planned as the key protected areas in the future. The method of collaborative analysis of the two models could improve the identification accuracy in detecting the conservation gaps and has certain universality for improving the efficiency of biodiversity conservation in high-intensity development areas.

Local intensity of artisanal gold mining drives mercury accumulation in neotropical oxbow lake fishes

Driven by surges in global gold prices and additional socio-economic factors, artisanal small-scale gold mining (ASGM) in the Global South is increasing and driving emissions of significant quantities of mercury (Hg) into the air and freshwater. Hg can be toxic to animal and human populations and exacerbate the degradation of neotropical freshwater ecosystems. We examined drivers of Hg accumulation in fish that inhabit oxbow lakes of Peru's Madre de Dios, a region with high biodiversity value and increasing human populations that depend on ASGM. We hypothesized that fish Hg levels would be driven by local ASGM activities, by environmental Hg exposure, by water quality, and by fish trophic level. We sampled fish in 20 oxbow lakes spanning protected areas and areas subject to ASGM during the dry season. Consistent with previous findings, Hg levels were positively associated with ASGM activities, and were higher in larger, carnivorous fish and where water had lower dissolved oxygen levels. In addition, we found a negative relationship between fish mercury levels associated with ASGM and the occurrence of the piscivorous giant otter. The link between fine-scale quantification of spatial ASGM activity and Hg accumulation, as indicated by the result that in the lotic environment, localized effects of gold mining activities are stronger drivers (77 % model support) of Hg accumulation than environmental exposure (23 %) constitutes a novel contribution to a growing body of literature on Hg contamination. Our findings provide additional evidence of high Hg exposure risks to neotropical human and top carnivore populations subject to the impacts of ASGM, which depend on freshwater ecosystems undergoing gradual degradation. The documented spatial variation in Hg accumulation and increased Hg levels in carnivorous fish should serve as a warning to human communities in Madre de Dios to avoid the proximity of high-intensity gold mining areas and minimize local carnivorous fish consumption.

Comparative study on seismic performance of prefabricated and cast-in-place underground structures under different site conditions

Since the seismic performance of prefabricated underground structures is not yet clear, they not have been constructed in high seismic intensity areas or poor sites. This paper aims to study the applicability of rectangular prefabricated (semi-rigid prefabricated, ASF, and rigid prefabricated, AMT) underground structures in soft soil sites located in high seismic intensity areas. The structures were compared with cast-in-place (CIP) underground structures. Three-dimensional soil-structure interaction advanced finite element models were established to simulate the seismic behavior of the three types of underground structures (ASF, AMT and CIP) constructed in two different sites (soft rock site and soft soil site). The pre-earthquake stress states, dynamic responses, and post-earthquake performance states of the three underground structures were systematically analyzed, considering various static and dynamic conditions. Additionally, the results of dynamic time history were compared with those of the standard procedures available in the literature. The results demonstrated that: i) site conditions have a significant effect on the structures’ static and dynamic responses, ii) the seismic response in soft soil site is much larger than that in soft rock site, but the ratio of response of prefabricated underground structures to that of CIP is almost the same for both soft soil and soft rock sites. Furthermore, as the peak ground acceleration increases, the percentage difference of inter-story displacement ratio (IDR) between ASF, AMT and CIP underground structures in soft soil site decreases, and iii) prefabricated underground structures can be used in both soft rock and soft soil sites. In addition, the seismic performance of ASF is better than that of the AMT structure, which is better than that of the CIP structure. However, when the ASF structure is built in a site with high seismic intensity and poor soil conditions, special consideration must be given to waterproofing measures for wall-slab joints or setting up tongue and groove to improve the connection stiffness and reduce the deformation.

MRI characteristics of lumbosacral dural arteriovenous fistulas.

Spinal dural arteriovenous fistulas located in the lumbosacral region are rare and present with nonspecific clinical signs. The purpose of this study was to find out the specific radiologic features of these fistulas. We retrospectively reviewed the clinical and radiological data of 38 patients diagnosed with lumbosacral spinal dural arteriovenous fistulas in our institution from September 2016 to September 2021. All patients underwent time-resolved contrast-enhanced three-dimensional MRA and DSA examinations, and were treated with either endovascular or neurosurgical strategies. Most of the patients (89.5%) had motor or sensory disorders in both lower limbs as the first symptoms. On MRA, the dilated filum terminale vein or radicular vein was seen in 23/30 (76.7%) patients with lumbar spinal dural arteriovenous fistulas and 8/8 (100%) patients with sacral spinal dural arteriovenous fistulas. T2W intramedullary abnormally high signal intensity areas were found in all lumbosacral spinal dural arteriovenous fistula patients, with involvement of the conus present in 35/38 (92.1%) patients. The "missing piece sign" in the intramedullary enhancement area was seen in 29/38 (76.3%) patients. Dilatation of the filum terminale vein or radicular vein is powerful evidence for diagnosis of lumbosacral spinal dural arteriovenous fistulas, especially for sacral spinal dural arteriovenous fistulas. T2W intramedullary hyperintensity in the thoracic spinal cord and conus, and the missing-piece sign could be indicative of lumbosacral spinal dural arteriovenous fistula.

Spatial and Temporal Patterns of Hydropower Development on the Qinghai–Tibet Plateau

The Qinghai–Tibet Plateau is rich in hydropower resources for China, and the development of these has an important impact on the sustainable development of the plateau. However, the research on the pattern and processes of hydropower development on the plateau is still lacking. Using both field investigation and collected data, we evaluated the density and intensity of hydropower development on the Tibetan Plateau over the past 40 years. The spatial and temporal patterns of hydropower development were analyzed by applying exploratory spatial data analysis methods to study the spatial aggregation of hydropower development on the Qinghai–Tibet Plateau since 1980. The results show that: (1) Hydropower development on the Qinghai–Tibet Plateau can be divided into four stages—(i) pre-1980, at the beginning of development, with a small number of power stations and a small installed capacity; (ii) the period from 1980 to 2005, which was dominated by small hydropower developments, and the number of hydropower stations increased seven-fold; (iii) the 2005–2014 period, which saw large-scale cascade development; and (iv) post-2014, when hydropower development mode changed from quantity-led to scale-led. (2) Significant differences in hydropower development areas on the Qinghai–Tibet Plateau regarding the density and intensity of development from east to west are constantly decreasing. (3) The increase in hydropower development density in the past 40 years is mainly due to the increasing aggregation effect of hydropower development absorption in the eastern region (the aggregation effect of western counties has not been shown). (4) While low hydropower development intensity is found in most areas of the Qinghai–Tibet Plateau, attention must be given to river protection problems in the eastern high-intensity areas; failure to do so will increase the aggregation effect of hydropower development aggregation and, ultimately, affect the sustainable development of the regional development of the Qinghai–Tibet Plateau.

Adaptive, multi-paddock, rotational grazing management alters foraging behavior and spatial grazing distribution of free-ranging cattle

Sustainable management of grazinglands depends upon understanding how management practices influence livestock movements in space and time. We conducted a ranch-scale (2,600-ha) social-ecological experiment to examine how foraging behavior of cattle differs between a single large herd rotated adaptively among paddocks (collaborative, adaptive rangeland management; CARM) versus continuous, season-long grazing of paddocks by small non-rotational herds (traditional rangeland management; TRM). We analyzed how differences in cattle movement patterns may be linked to reductions in cattle growth rates and diet quality in the CARM treatment, relative to TRM. Cattle in the CARM treatment exhibited more linear grazing pathways, moved at lower velocity while grazing, and exhibited longer grazing bouts early in the growing season compared to TRM cattle. Grazing time within any given 10 × 10 m area was distributed more unevenly across TRM vs. CARM paddocks in years with average or above-average precipitation, but not in dry years. In all years, areas of high and low grazing intensity were more spatially clustered in TRM than CARM paddocks. Movement patterns of cattle managed using adaptive, multi-paddock rotations at high stock density (CARM) are consistent with less selective foraging. Such cattle form a “grazing front” that moves across the paddock and distributes grazing pressure in a more spatially homogeneous fashion. In years with substantial forage production, TRM cattle spent more time than CARM cattle in preferred areas of the paddock and foraged in more circular patches. In dry years, however, both treatments resulted in similarly even grazing distribution, likely due to limited intra-paddock variation in forage quality and quantity. At the ranch scale, these different intra-paddock movement patterns led to reductions in animal growth rates and no overall effect of grazing management on forage production.

Pediococcus acidilactici pA1c® Improves the Beneficial Effects of Metformin Treatment in Type 2 Diabetes by Controlling Glycaemia and Modulating Intestinal Microbiota.

Type 2 diabetes (T2D) is a complex metabolic disease, which involves maintained hyperglycemia, mainly due to the development of an insulin resistance process. Metformin administration is the most prescribed treatment for diabetic patients. In a previously published study, we demonstrated that Pediococcus acidilactici pA1c® (pA1c) protects from insulin resistance and body weight gain in HFD-induced diabetic mice. The present work aimed to evaluate the possible beneficial impact of a 16-week administration of pA1c, metformin, or the combination of pA1c and metformin in a T2D HFD-induced mice model. We found that the simultaneous administration of both products attenuated hyperglycemia, increased high-intensity insulin-positive areas in the pancreas and HOMA-β, decreased HOMA-IR and also provided more beneficial effects than metformin treatment (regarding HOMA-IR, serum C-peptide level, liver steatosis or hepatic Fasn expression), and pA1c treatment (regarding body weight or hepatic G6pase expression). The three treatments had a significant impact on fecal microbiota and led to differential composition of commensal bacterial populations. In conclusion, our findings suggest that P. acidilactici pA1c® administration improved metformin beneficial effects as a T2D treatment, and it would be a valuable therapeutic strategy to treat T2D.

Seismic performance of precast double-column pier with UHPC-filled socket connections

Precast piers have been extensively investigated and applied in low seismic intensity areas, owing to the faster construction speed, limited traffic interruption, and environmental friendliness. However, few studies and engineering practices of the precast double-column piers (PDPs) located in high-intensity seismic areas have been reported. Therefore, in this study, a novel socket connection filled with ultra-high-performance concrete (UHPC) was proposed for the PDPs. The socket connections with concrete filled steel tube (CFST) are used to enhance the strength of the column-cap beam joints, at the same time the socket connections with the tooth-shaped shear keys are adopted at the column-footing joints to reduce the required anchorage length. The PDP with a scale ratio of 1:3 was constructed and then tested under the quasi-static load to investigate its seismic performance. Finally, a simplified analytical model of the socket connections was proposed based on the concept of the elastic foundation beam. The test results demonstrate that the damage of the specimen PDP was mainly concentrated at the bottom of the columns, and the damage at the damage ends of the PDP specimen was severer than that of the cast-in-place (CIP) specimen. The load-bearing capacity of the PDP is slightly higher than that of the corresponding CIP specimen, while the energy dissipation and displacement ductility of PDP are slightly smaller than those of the CIP specimen. The proposed model could accurately and efficiently capture the hysteretic behavior of the proposed PDP with socket connections.

Research on Bearing and Seismic Isolation Design of Extrodosed Cable-stayed Bridge With Ultra-wide A-type Tower in High-intensity Areas

In order to improve the support and isolation performance of the escape cable-stayed bridge with super wide A-type tower in high-intensity areas, the paper takes Jingyuan Jinshatan Yellow River Bridge as the background, based on the finite element method, and takes the design of 20000 ton isolation bearing as the case, optimizes the design parameters, structural composition and friction pair settings of the bearing, and develops the actual bearing to meet the needs of the project by combining simulation analysis and experimental testing. The results of time history analysis show that the displacement of the strength support seat at the bottom of the pier and the expansion joint at the beam end can meet the design requirements.

Seismic Design Optimization of Frame-multi-ribbed Composite Wall Structure

To explore the optimization seismic design of frame-multi-ribbed composite wall structure, firstly the finite element model of a six story frame-multi-ribbed composite wall structure is established based on the software of SAP2000. Secondly the critical design parameters of multi story frame-multi-ribbed composite wall structure under seismic action are analysised using finite element analysis software. Finally the seismic response of the structure under different rib combinations and the optimal arrangement rule of the structure are studied. The results reveals that the lateral stiffness of the structure cannot be effectively improved by increasing the number of rib grids of the multi ribbed composite wall. The results can provide a theoretical basis for the design of the multi story frame-multi-ribbed composite wall structure in the medium and high earthquake intensity area.

Ossification of the anterior longitudinal ligament affects the severity and distribution of neurological deficits following spinal cord injury without radiological abnormality

BackgroundThe incidence of spinal cord injury without radiological abnormality (SCIWORA) is increasing among older adults in developed countries. SCIWORA is commonly associated with ossification of the spinal ligament, specifically the ossification of the posterior longitudinal ligament (OPLL) and ossification of the anterior longitudinal ligament (OALL). OALL induces segmental spinal fusion and alters the biomechanical properties of the cervical spine; however, whether OALL modulates the severity of SCIWORA remains unknown. This study aimed to investigate the influence of OALL on the severity and distribution of neurological deficits following SCIWORA. MethodsThis retrospective study included 122 patients with SCIWORA who were admitted to our hospital from April 2008 to March 2022. The neurological function of all the included patients was assessed via the American Spinal Injury Association (ASIA) Impairment Scale (AIS) at admission. Magnetic resonance imaging (MRI) and computed tomography were performed within 48 h of trauma. Central cord syndrome (CCS) was defined as the upper-extremity ASIA motor score being at least 10 points lesser than the lower-extremity motor score. ResultsThe study included 122 patients with a mean age of 65.1 years. Comparing mild (AIS grades C or D) and severe (AIS grades A or B) neurological deficits revealed that the former was independently associated with ground-level falls, OALL, and absence of prevertebral T2 high-intensity area on MRI. Although 39% of patients with SCIWORA exhibited OPLL as an etiology of cervical stenosis, OPLL demonstrated no significant effect on the severity of neurological deficits. CCS occurrence was independently associated with OALL and a larger cross-sectional cord area on MRI. Patients with OALL had significantly higher lower-extremity ASIA motor scores than those without OALL. ConclusionsOALL was significantly associated with mild neurological deficits in the lower extremities and with the occurrence of CCS after SCIWORA.

Integration of multiple prognostic predictors in a porcine spinal cord injury model: A further step closer to reality.

Spinal cord injury (SCI) is a devastating neurological disorder with an enormous impact on individual's life and society. A reliable and reproducible animal model of SCI is crucial to have a deeper understanding of SCI. We have developed a large-animal model of spinal cord compression injury (SCI) with integration of multiple prognostic factors that would have applications in humans. Fourteen human-like sized pigs underwent compression at T8 by implantation of an inflatable balloon catheter. In addition to basic neurophysiological recording of somatosensory and motor evoked potentials, we introduced spine-to-spine evoked spinal cord potentials (SP-EPs) by direct stimulation and measured them just above and below the affected segment. A novel intraspinal pressure monitoring technique was utilized to measure the actual pressure on the cord. The gait and spinal MRI findings were assessed in each animal postoperatively to quantify the severity of injury. We found a strong negative correlation between the intensity of pressure applied to the spinal cord and the functional outcome (P < 0.0001). SP-EPs showed high sensitivity for real time monitoring of intraoperative cord damage. On MRI, the ratio of the high-intensity area to the cross-sectional of the cord was a good predictor of recovery (P < 0.0001). Our balloon compression SCI model is reliable, predictable, and easy to implement. By integrating SP-EPs, cord pressure, and findings on MRI, we can build a real-time warning and prediction system for early detection of impending or iatrogenic SCI and improve outcomes.

Primary synovial sarcoma of the shoulder: Case report of the “triple sign” on proton density magnetic resonance imaging

The first case of synovial sarcoma was published in 1893. The disease is a type of primary malignancy of the soft tissues. It is a rare and aggressive neoplasm of unknown tissue origin, characterized by strong metastatic potential and poor prognosis. The present case of a 64-year-old male patient with pain and swelling in his right shoulder and progressive loss of movement demonstrates an uncommon location for the neoplasm. Magnetic resonance proton-density fat-suppressed turbo spin-echo sequences show a heterogeneous mass in the right shoulder. The lack of homogeneity in the signal has been described in medical literature as the "triple sign" and is represented by low, intermediate, and high signal intensity areas through the neoplasm. Visible serpentine vessels spread through the tumor. There was a visible metastatic disease in the regional lymph nodes and metastatic foci in the adjacent bones. Pathological analysis of the tumor confirmed the diagnosis of biphasic synovial sarcoma. An oncological committee advised chemotherapy and radiotherapy. More prominent magnetic resonance imaging findings in synovial sarcoma that may facilitate the diagnostic process are the inhomogeneity and "triple sign" in proton density and T2 sequences, multilobulated tumors, septa, irregular borders, serpentine vascular channels, engagement of the adjacent bones and bone marrow, and involvement of the joint synovia.