Areas Of Low Intensity Research Articles

Characterization of plaque hemorrhage with optical coherence tomography imaging in statin-treated patients with coronary artery disease: comparison with noncontrast T1-weighted MRI

Abstract Background Plaque hemorrhage is a phenotypic feature of coronary lesions associated with future coronary events. Noncontrast T1-weighted MRI has a potential to non-invasively identify plaque hemorrhage. Plaque to myocardium ratio (PMR) evaluated by noncontrast T1-weighted MRI has been shown to pathohistologically correspond to plaque hemorrhage. In several case reports comparing OCT images with coronary specimens, low intensity area without its attenuation was observed at lesions presenting plaque hemorrhage. However, whether the association of this OCT-derived feature with PMR remains to be elucidated yet. Purpose To characterize plaque hemorrhage in vivo by comparing with OCT and noncontrast T1-weighted MRI. Methods The current study prospectively enrolled 80 statin-treated patients with coronary artery disease requiring elective PCI. A total of 103 target lesions were imaged by both noncontrast T1-weighted MRI and OCT prior to PCI. Plaque hemorrhage on noncontrast T1-weighted MRI was defined as PMR>1.0. On OCT imaging analysis, low intensity area without attenuation (LIA) was defined according to the following criteria; (1) area presenting homogeneous low intensity signals, (2) clear border and (3) no signal attenuation behind its area. The maximum arc of LIA was manually measured. OCT-derived plaque features were compared in lesions with and without PMR>1.0. Results PMR>1.0 was observed at 49.5% of analyzed lesions. Patients with PMR>1.0 were more likely older (72 vs. 66 years, p=0.02), whereas there was no significant difference in on-treatment LDL-C levels (median: 80 vs. 77 mg/dL, p=0.62) (Table). On lesion-based analysis, while fibrous cap thickness was similar between the two groups (80 vs. 100um, p=0.10), a larger lipid arc (270 vs. 230º, p=0.02) and a greater frequency of macrophage (90.2 vs. 53.9%, p<0.01), layered plaque (62.8 vs. 32.7%, p=0.003) and cholesterol crystal (70.6 vs. 30.8%, p<0.001) were observed at lesions with PMR>1.0. Furthermore, lesions with PMR>1.0 more frequently exhibited LIA (66.7 vs. 19.2%, p<0.001) and its greater maximum arc (33 vs. 0º, p<0.001) (Figure). Of note, PMR was significantly correlated to the maximum arc of LIA (r=0.51, p<0.001) (Figure). Multivariate analysis demonstrated LIA and cholesterol crystal as independent OCT-derived features associated with PMR>1.0 (Table). Conclusion In statin-treated patients, 49.5% of analyzed lesions presented PMR>1.0. Coronary lesions with PMR>1.0 more frequently harbored LIA and cholesterol crystals, in addition to other vulnerable OCT features. Our findings suggest OCT-derived LIA as a potential signature of plaque hemorrhage. Given that cholesterol crystal was another feature of PMR>1.0, plaque inflammation driven by cholesterol crystallization may exist at plaque hemorrhage despite statin use. Whether anti-inflammation agent could modulate plaque hemorrhage requires future investigation.

Does the distribution of light intensity within the barn impact broiler production and welfare?

ABSTRACT 1. The objective of this study was to determine if rearing broilers under variable light intensity (VLI) impacted their welfare or productivity. 2. Ross 308 broilers (n = 7,256) were reared until 35 d of age and exposed to a uniform intensity of 10 lux (CON) or VLI with low intensity areas of 2–5 lux proximal to the walls and high intensity areas of 84–133 lux proximal to feeders. 3. The data were analysed as a complete randomised design using an analysis of variance. Significance was declared when p ≤ 0.05. 4. Applying VLI resulted in increased feed intake early in life but had no impact on body weight. Overall efficiency was improved in the CON treatment. Mortality diagnoses of skeletal problems were reduced under VLI. Treatment had no impact on footpad, hock or gait score, heterophil to lymphocyte ratio or melatonin concentration. Birds performed certain behaviours in specific locations within the room, independent of light intensity treatment. 5. In conclusion, raising broilers under VLI had little impact on production or most welfare parameters assessed in this study. However, satisfying the bird’s preference for different light intensities may improve welfare.

The role of primary healthcare amid the COVID-19 pandemic: Evidence from the Family Health Strategy in Brazil

This paper investigates the role of primary healthcare in mitigating the consequences of the COVID-19 pandemic, focusing on the Brazilian Family Health Strategy (ESF) as a case study. ESF is Brazil’s major primary care initiative, with prior evidence indicating its effectiveness in improving various health outcomes. The COVID-19 pandemic submitted the Brazilian healthcare system to a rigorous and unprecedented stress test, whose repercussions are still under study. Using comprehensive administrative microdata from 2016 to 2022 encompassing dimensions related to mortality, healthcare service, supply of family health teams, and vaccination coverage, our empirical strategy accounts for heterogeneous effects based on program intensity and pandemic evolution of the 5570 Brazilian municipalities. Our findings reveal that municipalities with high-intensity of ESF coverage (i.e. stronger primary care) experienced 347.93 (95% CI: 289.04, 406.81) fewer COVID-19 and cardiorespiratory deaths per million inhabitants throughout the pandemic period, compared to those in low-intensity ESF areas, despite sharing similar profiles of deaths from respiratory and cardiovascular causes. Among the channels contributing to this relative performance, high-intensity ESF municipalities were found to engage in more home-based primary care visits and health promotion activities while maintaining a similar supply of community health workers. Additionally, they achieved higher vaccination coverage, and these effects were more pronounced in areas with greater ESF presence, emphasising the importance of primary care coverage. In conclusion, our findings underscore the relevance of strong primary care in mitigating the consequences of the pandemic and addressing post-pandemic health challenges.

Comparisons of magnetic resonance imaging, histopathological and Ki-67 labeling index findings in a single myxofibrosarcoma: a case report

BackgroundMyxofibrosarcoma is a myxoid soft tissue sarcoma showing T2 high intensity on magnetic resonance imaging. However, myxofibrosarcoma is a heterogeneous sarcoma with both myxoid and cellular portions. Magnetic resonance imaging findings were obtained MRI findings for comparison with histological and Ki-67 immunohistochemical features, in different portions of one myxofibrosarcoma.Case presentationMagnetic resonance imaging observations were compared with gross pathological and microscopic findings of a myxofibrosarcoma from a 50-year-old Japanese female. The Ki-67 labeling indices of different portions of the tumor, that is, the myxoid, cellular, and histologically confirmed infiltrative margin portions (pathological tail sign), were compared. The T2 low intensity area was more cellular than the T2 high intensity area, while the cellular portion had a significantly higher Ki-67 index than the myxoid portion (p = 0.0313). The portions with the pathological tail sign had a significantly higher Ki-67 labeling index than those without this sign (p = 0.0313).ConclusionsMore cellular portions of a myxofibrosarcoma correspond to more areas of the tumor showing aggressive features. Furthermore, our data also support the hypothesis of high aggressiveness being associated with the pathological tail sign in myxofibrosarcoma. To our knowledge, this is the first case report to describe comparisons among the imaging findings, histological features, and Ki-67 immunohistochemistry results for different portions of one myxofibrosarcoma.

Accuracy of commercial ELISA and ICT for screening schistosomiasis infections at a low endemicity area in Brazil.

Control interventions recommended by the World Health Organization have successfully resulted in low-intensity schistosomiasis transmission areas. To achieve elimination of transmission, new diagnostic screening tools are needed to overcome less than adequate sensitivity of the currently used Kato-Katz faecal thick smear method. Ideally, in-house serological tests should be avoided due to not having a continuous supply of kits as would be necessary for large population studies. Quality assurance provided by manufacturers and proper performance evaluations are also needed. We evaluated the accuracy of two commercially available serology tests as screening methods for detecting light schistosomiasis infections. Serum samples were collected in 2015 from individuals living in a low-endemicity locality in northeastern Brazil and deposited in a biorepository. We evaluated immunoglobulin G (IgG) and IgM enzyme-linked immunosorbent assays (ELISAs) and an immunochromatographic test (ICT). The Helmintex method was used to define true-positive samples. Overall sensitivity was close to 90% for both the IgG ELISA and ICT, yet specificity was 28% and 18%, respectively. For the IgM ELISA, the values were estimated to be 55% and 43%, respectively. Poor specificity and positive predictive values prevent these tests from being recommended for screening populations in low-intensity schistosomiasis-endemic areas.

Three-dimensional visualization and detection of early bruise in apple based on near-infrared hyperspectral imaging coupled with geometrical influence correction

Visible-near-infrared (Vis-NIR) spectral imaging holds great promise for the automatic detection of fruit defects. However, uneven brightness resulting from fruit geometry and the limitations of one-directional imaging significantly restrict the current detection to a limited area. This study presents a rotation measurement system that combines a line-scan NIR-hyperspectral imaging (HSI) camera with a laser profile. A total of 72 apple samples with bruises in the central and edge regions were prepared. A 360° scanning approach was employed to collect HSI and shape data from the entire surface of the samples over a 6-h post-bruising period. Height and angle corrections were applied to eliminate the surface geometric influences on the HSI data, resulting in improved reflectance spectrum uniformity. A two-step principal component analysis method was employed for image enhancement, followed by a straightforward bruise detection technique using global segmentation and connected-domain selection. The results demonstrated an overall improvement in bruise detection over time. Moreover, the correction significantly enhanced the detection accuracy. After 6 h of bruising, the corrected data achieved a classification accuracy of 90.3% and an identification rate of 83.3% for central bruises and 61.1% for edge bruises, whereas the uncorrected data yielded 70.8%, 58.3%, and 31.9%, respectively. Thus, this study successfully detected early bruising across the entire surface of apples and improved the detection in low-intensity edge areas. The proposed method has the potential to contribute to the comprehensive evaluation of agricultural products with irregular geometries.

Burning and plume flow behaviors of annular pool fires: with and without air entrainment through the pool center.

Annular pool fires, frequently happened in chemical industries, have a significant influence on environmental pollution. Air pollution, greenhouse gas emissions, water pollution, and soil contamination are general ways of environmental hazards caused by the annular pool fires. This study built upon our previous study (Environ. Sci. Pollut. Res., 2023, 30(21): 59781-59792.), and extended to investigate the combustion and fire plume flow behaviors of annular pool fires, both with and without air entrainment through the hollow center of the annular pool. Results show that when there is no air entrainment through the hollow center, the low combustion intensity area at the plume's central axis gradually extends while the high combustion intensity area concentrates at higher places and the flame height increased by nearly 40% from a solid pool (Din/Dout = 0) to the annular pool (Din/Dout = 0.80). Additionally, the area with high combustion intensity is more concentrated at a higher position. The combustion of annular pool fires was found to be dominated by non-premixed diffusion combustion. The center of the annular pool fires is dominated by air prior to flame merging and by fuel vapor after the merging occurs. For annular pool fires with air entrainment through the center of the pool, the combustion intensity increases as Din/Dout at the plume base increases. And, the flame height decreased by nearly 25% as Din/Dout increases. Flame burning occurs both on the outside and inside of the plume, exhibiting a "double layer" combustion characteristic. It reveals that the combustion of the fire plume transitions to premixed diffusion combustion. The center of the annular pool fire is predominantly composed of air. Understanding and controlling annular pool fires can lead to new methods for remediating fuel spills, reducing pollution from combustion, and advancing research in fluid mechanics.

MR Imaging Findings of Uterine Adenomatoid Tumors.

Adenomatoid tumor is a rare benign genital tract neoplasm of mesothelial origin. Uterine adenomatoid tumors occur in the outer myometrium and may mimic leiomyomas. Because hormonal treatment is not applicable to adenomatoid tumors and laparoscopic enucleation is not easy as myomectomy, it is important to differentiate adenomatoid tumors from leiomyomas for the adequate treatment. The purpose of this study is to evaluate the MRI findings of adenomatoid tumor for the differentiation from leiomyoma. MRI findings of surgically proven 10 uterine adenomatoid tumors in 9 women were retrospectively evaluated with correlation to histopathological findings. All 10 tumors appeared as solid myometrial masses and showed heterogeneous signal intensity with admixture of partially ill-defined slight high-intensity areas containing abundant tubular tumor cells and well-defined myoma-like low-intensity areas reflecting smooth muscle hypertrophy on T2WI including 4 lesions with peripheral ring-like high intensity. High-intensity areas on T2WI tended to show high intensity on diffusion-weighted imaging (DWI) with relatively high apparent diffusion coefficient (ADC), suggesting T2 shine-through effect due to abundant tubules. Intra-tumoral hemorrhage revealed on MRI was rare. Early intense contrast-enhanced areas on dynamic contrast-enhanced study were observed dominantly within the high-intensity areas but rarely within the low-intensity areas on T2WI. The outer myometrial mass with the admixture of well-defined low- and ill-defined high-intensity areas on T2WI may be suggestive of adenomatoid tumor. Peripheral ring-like high intensity on T2WI and DWI may also be suggestive. Dynamic contrast-enhanced MR study may be helpful for the differentiation from leiomyoma.

Effects of cooling roofs on mitigating the urban heat island and human thermal stress in the Pearl River Delta, China

The Weather Research and Forecasting model was employed to simulate the effects of cooling roofs on the urban heat island effect and human thermal stress in the Pearl River Delta region, China, in summer (June–August) 2014. It was found that cooling roofs can reduce the 2-m air and ground-surface temperature, wind speed, and planetary boundary layer height, while increasing the specific and relative humidity, in urban areas. The effects can influence the entire urban boundary layer, especially in commercial/industrial areas in the daytime. Cooling roofs can effectively mitigate the urban heat island effect, and the mitigation of white roofs is more significant than that of green roofs. The mitigation of the urban heat island effect is stronger in commercial/industrial areas than in low-intensity residential areas. The city-wide 2-m and ground-surface urban heat island intensity induced by white roofs can reduce by 1.5 °C and 4.8 °C at noon, while the corresponding decreases induced by green roofs can reach 0.7 °C and 1.9 °C, respectively. White roofs improve human thermal comfort both in the daytime and at nighttime. With white roofs, three city-wide thermal-stress indices (wet-bulb globe temperature, apparent temperature, and humidity index) can be reduced at noon by 0.8 °C, 1.3 °C and 1.5 °C, respectively. Green roofs mostly improve human thermal comfort at nighttime but even deteriorate it in the daytime. The above three indices decrease by less than 0.5 °C in different urban categories at nighttime with green roofs.

Study of the Failure Mechanism of Soft Rock Mining Roadways Based on Limit Analysis Theory

To study the deformation and failure mechanisms of soft rock mining roadways, the 1506 return airway of Anyang Coal Mine is taken as the engineering background. Based on limit analysis theory, a failure model based on a rigid slider system is constructed to assess the failure of the soft rock surrounding a roadway. The formulas for calculating the self-weight power of the slider in the velocity discontinuity line of the rock surrounding the roadway, the work power of the surrounding rock pressure, and the energy dissipation rate of the velocity discontinuity line are derived, and the upper limit objective function of the velocity discontinuity line height is obtained. The failure characteristics and fracture evolution process of the surrounding rock under different mining stresses are analyzed by means of physical similarity simulations. The simulation results show that shear failure occurs first on the roadway side due to stress concentration. The fissures expand along the bottom angle of the roadway to the blind support area and the low-intensity support area. The cracks weaken the support strength of the angled anchor cable and bolt in the roadway shoulder. Under the action of roof pressure, the status of the rock mass inside and outside the shear slip zone changes from static to dynamic. This causes deformation and failure of the roadway roof, side, and floor.

Short-Term Effects of Prescribed Burn Seasonality on the Understory in a Pinus nigra Arnold subsp. salzmannii (Dunal) Franco Mediterranean Forest

Worsening climate change and increasing temperatures generate more sever and extended wildfires, raising concerns about ecosystem services. Prescribed burns (PB) are used to reduce forest fuel loads. Improving knowledge regarding the vegetation response after PB is essential for generating common points for monitoring ecological burning effects and generating a protocol or practice guide. We compared the PB seasonality of low-intensity (spring, summer, and autumn) and unburned areas in a total of 12 plots in Pinus nigra Arnold ssp. salzmannii Mediterranean forest. Our vegetation analysis was short term (one year after each PB). We analyzed vegetation coverage, α-diversity (Pielou, Simpson, and Shannon’s index), life forms, and fire-adapted traits using the Canfield transect method, followed by statistical analyses such as non-metric multidimensional scaling (NMDS) and two-way ANOVA. α-diversity was significantly decreased (>55% of dissimilarity) in the burned plots during each season, with the lowest values after summer PB (69% of dissimilarity) when comparing the burned and unburned plots. There was a significant increase in hemicryptophytes (15−20%) and geophyte coverage (from 6% to 14%, or from 4% to 8% in certain cases) in the burned plots after PB seasonality; however, the phanerophytes were reduced (from 13% to 5%). Resprouters were more dominant after PB (an increase of 15–20%), which indicates that resprouters have a faster recovery and generate a fuel load quickly for highly flammable species such as Bromus after low-intensity burning. This suggests that low-intensity prescribed burning may not be the best methodology for these resprouting species. This study helps to understand how burning in the early season can affect inflammable vegetation and the change in fuel that is available in semi-arid landscapes. This is key to achieving the basis for the development of a standardized system that allows for the efficient management of forest services in order to reduce wildfire risks. One objective of this line of research is to observe the effects of recurrent burning in different seasons on vegetation, as well as plant−soil interaction using the microbial and enzyme soil activity.

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.

Metabolic Anomaly Appearance Aware U-Net for Automatic Lymphoma Segmentation in Whole-Body PET/CT Scans.

Positron emission tomography-computed tomography (PET/CT) is an essential imaging instrument for lymphoma diagnosis and prognosis. PET/CT image based automatic lymphoma segmentation is increasingly used in the clinical community. U-Net-like deep learning methods have been widely used for PET/CT in this task. However, their performance is limited by the lack of sufficient annotated data, due to the existence of tumor heterogeneity. To address this issue, we propose an unsupervised image generation scheme to improve the performance of another independent supervised U-Net for lymphoma segmentation by capturing metabolic anomaly appearance (MAA). Firstly, we propose an anatomical-metabolic consistency generative adversarial network (AMC-GAN) as an auxiliary branch of U-Net. Specifically, AMC-GAN learns normal anatomical and metabolic information representations using co-aligned whole-body PET/CT scans. In the generator of AMC-GAN, we propose a complementary attention block to enhance the feature representation of low-intensity areas. Then, the trained AMC-GAN is used to reconstruct the corresponding pseudo-normal PET scans to capture MAAs. Finally, combined with the original PET/CT images, MAAs are used as the prior information for improving the performance of lymphoma segmentation. Experiments are conducted on a clinical dataset containing 191 normal subjects and 53 patients with lymphomas. The results demonstrate that the anatomical-metabolic consistency representations obtained from unlabeled paired PET/CT scans can be helpful for more accurate lymphoma segmentation, which suggest the potential of our approach to support physician diagnosis in practical clinical applications.

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.

How does exposure to climate risk contribute to gentrification?

The growing frequency and intensity of extreme weather events are influencing people's decision-making about the cities in which they will live in the future. The subsequent societal impacts of greater exposure to climate hazards require transformative action in coastal cities. However, few studies have considered the aggregate impacts of risk-induced household migration behaviour. In this study, we employ a difference-in-differences framework to examine hurricane-prone coastal cities across the US to explore the cumulative consequences of residential migration in response to climate risk exposure. Our results indicate that the cumulative in-migration due to climate risks may cause demographic shifts in areas where climate risk is relatively low, increasing climate gentrification. Climate-risk-induced migration to low storm intensity areas is associated with a 13.8 % increase in median income, while in-migration to lower flood-risk areas decreases non-Hispanic African American residents by 18.9 %. These results suggest that state and local governments should promote effective local-level climate adaptations to address climate risks, not only to ensure urban sustainability in hazard-prone areas but also to curb potential social inequality in low-risk areas.

C3DBed: Facial micro-expression recognition with three-dimensional convolutional neural network embedding in transformer model

Facial micro-expression is often used for emotional recognition of people in a high-risk or pressure scene, which may reflect genuine emotions due to the low intensity of facial action units. Current methods focus on locating regions with emotional changes and cropping these regions for local feature extraction. However, these methods may lead to the problem of information redundancy caused by overlapping cropped regions. This paper proposes a novel three-dimensional convolutional neural network embedding in the transformer model (C3DBed). This model learns the attention weight of each local region of the micro-expression image, thereby perceiving the detail changes of the facial image and extracting robust local detail features. Solve the problem of model complexity and information redundancy caused by low-intensity local area positioning of facial muscle movement. The experiment results demonstrated that the proposed C3DBed model achieved competitive performance with accuracy rates of 78.04%, 77.64%, and 75.73% on SMIC, CASME II, and SAMM datasets, respectively.

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.

Peculiarities of spinal epidural abscess in COVID-19 patients: a literature review

During the SARS-CoV-2 pandemic, some authors described an increased incidence of primary Spinal Epidural Abscess (SEA) in COVID-19 patients with clinical and radiological peculiarities. Early recognition of this disease remains challenging, resulting in delayed diagnosis and significant morbidity and mortality. The authors performed a systematic review of the literature in PubMed, Cochrane, and Scopus about the traditional form of SEA comparing the main features related to COVID-19 SEA. The search was performed from 1990 to 2020. Magnetic Resonance Imaging with contrast is mandatory to recognize this kind of lesion in order to obtain a differential diagnosis. COVID-19 SEAs are generally active abscesses, with a large cystic component. Gadolinium-enhanced MR images can aid in the definition of the age and consistency of the abscess. A rim of tissue that enhances after the injection of gadolinium represents granulation tissue; liquid pus is associated with an area of low signal intensity on T1-weighted images. This new type of SEA in COVID-19 patients showed several differences also in clinical features. No evidence of an external infective source was found (spondylodiscitis, surgery, or percutaneous treatment). None of the patients was a drug abuser and MSSA was the only responsible pathogen. The cervicothoracic spine was the most involved site. Further studies are needed to confirm these preliminary findings.

Resuscitated sudden cardiac arrest related to intraplaque haemorrhage and coronary artery spasm.

A 72-year-old man with a history of chronic kidney disease, dyslipidaemia, and hypertension felt chest tightness after walking uphill and sat down to rest. Shortly thereafter, he suddenly collapsed, and cardiopulmonary resuscitation was started by a nearby family member. The initial electrocardiogram waveform was ventricular fibrillation, which was restored to sinus rhythm with an automated external defibrillator. He was transported to our hospital. No significant electrocardiographic changes, but positive serum troponin was observed on arrival. Emergency coronary angiography was performed, revealing a moderate stenosis in the proximal left anterior descending coronary artery (Panel A) which was functionally significant (Panel B). Optical coherence tomography showed a large eccentric plaque with a confined low-intensity plaque with strong signal attenuation (Panel C) and some areas of low intensity and low attenuation (Panel D), highly suggestive of intraplaque haemorrhage (IPH) (see Supplementary data online, Video S1).1 A stent implantation was subsequently performed (Panel E). On the ninth day of hospitalization, an acetylcholine provocation test was performed for the right coronary artery and severe diffuse coronary spasm was induced (Panels F and G) accompanied by chest tightness and ST elevation on electrocardiogram, leading to a diagnosis of coronary spastic angina.

Benefits of high-dielectric pad for neuroimaging study in 7-Tesla MRI

This study aimed to evaluate whether the use of a high-dielectric pad is effective in increasing transmit and receive sensitivity in areas of low signal intensity in the human brain at high magnetic fields and assess its usefulness in neuroimaging studies. The novelty of this study lies in the first reported use of diffusion tensor imaging (DTI) results to evaluate the effect of the pad on neuroimaging. Six volunteers underwent MR scanning using a 7 T MR system. T1-weighted images (T1w) and diffusion-weighted images (DWI) were acquired to demonstrate the benefits of a high-dielectric pad made of barium titanate (BaTiO3). For all imaging experiments, two datasets were acquired per person, one with and one without a high-dielectric pad. Enhancement of signal sensitivity in neuroimaging has been analyzed by DTI study. Higher signal intensities and spatial contrast were demonstrated in the in T1w images acquired using high-dielectric pad than in those acquired without high-dielectric pad. Especially in DTI studies, increased quantitative anisotropy (QA) signals were observed in the corticospinal tract (CST), frontopontine tract (FPT), splenium of corpus callosum (SCC), fornix (FX), inferior fronto-occipital fasciculus (IFOF), cerebellum (CB), middle cerebellar peduncle (MCP), and body of corpus callosum (BCC) (FDR < 0.05). The signal differences accounted for an overall 20% increase. A high-dielectric pad is effective in enhancing signal intensity in human brain images acquired using 7 T MRI. Our results show that the use of such pad can increase the spatial resolution, tissue contrast, and signal intensity in neuroimaging studies. These findings suggest that high-dielectric pads may provide a relatively simple and low-cost method for spatiotemporal brain imaging studies.