bluuebunny/crossref_metadata_2025 huggingface dataset:
Improvement of 2D cine image quality using 3D priors and cycle generative adversarial network for low field MRI‐guided radiation therapy
Authors: Dong Yuyan , Yang Fei , Wen Jie , Cai Jing , Zeng Feiyan , Liu Mengqiu , Li Shuang , Wang Jiangtao , Ford John Chetley , Portelance Lorraine , Yang Yidong
Published: December 2023

Background

Cine magnetic resonance (MR) images have been used for real‐time MR guided radiation therapy (MRgRT). However, the onboard MR systems with low‐field strength face the problem of limited image quality.

Purpose

To improve the quality of cine MR images in MRgRT using prior image information provided by the patient planning and positioning MR images.

Methods

This study employed MR images from 18 pancreatic cancer patients who received MR‐guided stereotactic body radiation therapy. Planning 3D MR images were acquired during the patient simulation, and positioning 3D MR images and 2D sagittal cine MR images were acquired before and during the beam delivery, respectively. A deep learning‐based framework consisting of two cycle generative adversarial networks (CycleGAN), Denoising CycleGAN and Enhancement CycleGAN, was developed to establish the mapping between the 3D and 2D MR images. The Denoising CycleGAN was trained to first denoise the cine images using the time domain cine image series, and the Enhancement CycleGAN was trained to enhance the spatial resolution and contrast by taking advantage of the prior image information from the planning and positioning images. The denoising performance was assessed by signal‐to‐noise ratio (SNR), structural similarity index measure, peak SNR, blind/reference‐less image spatial quality evaluator (BRISQUE), natural image quality evaluator, and perception‐based image quality evaluator scores. The quality enhancement performance was assessed by the BRISQUE and physician visual scores. In addition, the target contouring was evaluated on the original and processed images.

Results

Significant differences were found for all evaluation metrics after Denoising CycleGAN processing. The BRISQUE and visual scores were also significantly improved after sequential Denoising and Enhancement CycleGAN processing. In target contouring evaluation, Dice similarity coefficient, centroid distance, Hausdorff distance, and average surface distance values were significantly improved on the enhanced images. The whole processing time was within 20 ms for a typical input image size of 512 × 512.

Conclusion

Taking advantage of the prior high‐quality positioning and planning MR images, the deep learning‐based framework enhanced the cine MR image quality significantly, leading to improved accuracy in automatic target contouring. With the merits of both high computational efficiency and considerable image quality enhancement, the proposed method may hold important clinical implication for real‐time MRgRT.
Predictive stroke risk model with vision transformer‐based Doppler features
Authors: Lo Chung‐Ming , Hung Peng‐Hsiang
Published: December 2023

Background

Acute stroke is the leading cause of death and disability globally, with an estimated 16 million cases each year. The progression of carotid stenosis reduces blood flow to the intracranial vasculature, causing stroke. Early recognition of ischemic stroke is crucial for disease treatment and management.

Purpose

A computer‐aided diagnosis (CAD) system was proposed in this study to rapidly evaluate ischemic stroke in carotid color Doppler (CCD).

Methods

Based on the ground truth from the clinical examination report, the vision transformer (ViT) features extracted from all CCD images (513 stroke and 458 normal images) were combined in machine learning classifiers to generate the likelihood of ischemic stroke for each image. The pretrained weights from ImageNet reduced the time‐consuming training process. The accuracy, sensitivity, specificity, and area under the receiver operating characteristic curve were calculated to evaluate the stroke prediction model. The chi‐square test, DeLong test, and Bonferroni correction for multiple comparisons were applied to deal with the type‐I error. Only p values equal to or less than 0.00125 were considered to be statistically significant.

Results

The proposed CAD system achieved an accuracy of 89%, a sensitivity of 94%, a specificity of 84%, and an area under the receiver operating characteristic curve of 0.95, outperforming the convolutional neural networks AlexNet (82%, p < 0.001), Inception‐v3 (78%, p < 0.001), ResNet101 (84%, p < 0.001), and DenseNet201 (85%, p < 0.01). The computational time in model training was only 30 s, which would be efficient and practical in clinical use.

Conclusions

The experiment shows the promising use of CCD images in stroke estimation. Using the pretrained ViT architecture, the image features can be automatically and efficiently generated without human intervention. The proposed CAD system provides a rapid and reliable suggestion for diagnosing ischemic stroke.
Technical note: Determination of proton linear energy transfer from the integral depth dose
Authors: Yao Weiguang , Farr Jonathan B. , Mossahebi Sina , Yi Byongyong , Chen Shifeng
Published: December 2023

Background

Proton linear energy transfer (LET) is associated with the relative biological effectiveness of radiation on tissues. Monte Carlo (MC) simulations have been known to be the preferred method to calculate LET. Detectors have also been built to measure LET, but they need to be calibrated with MC simulations.

Purpose

To propose and test a MC‐free method for determining LET from the measured integral depth dose (LFI) of the protons of interest.

Method and materials

LFI consists of three steps: (1) IDD measurements, (2) extraction of energy spectrum (ES) from the IDD, and (3) LET determination from the extracted ES and the stopping power of each energy. To validate the accuracy of the extraction of ES, we use Gaussian ES to synthesize IDD, extract ES from the synthesized IDD, and then compare the original (ground truth) and extracted ES. LETs calculated from the original and extracted ES are also compared. To obtain the LET of protons of interest, we measure IDDs by a large‐area plane‐parallel ionization chamber in water. Finally, TOPAS MC is employed to simulate IDDs, ES, and LETs. From the simulated IDD, the extracted ES and LET are compared with the simulations from TOPAS MC.

Results

From the synthesized IDDs, the LETs agreed excellently when the peak energies ≥10 and 1.25 MeV with depth resolutions 0.1 and 0.01 mm, respectively. For energy <1.25 MeV, even higher depth resolution than 0.01 mm is required. From the MC simulated IDDs, our track‐averaged LET excellently agreed with MC simulation, but not the LETd. Our LETd was smaller than MC simulated LETd in the shallow region but larger in the distal Bragg peak region.

Conclusion

LET can be accurately determined from the IDD. This method can be used in the clinic to commission or validate LETs from other measurement methods or a treatment planning system.
Extension of the cone‐beam CT field‐of‐view using two complementary short scans
Authors: Belotti Gabriele , Fattori Giovanni , Baroni Guido , Rit Simon
Published: December 2023

Background

Robotic C‐arm cone‐beam computed tomography (CBCT) scanners provide fast in‐room imaging in radiotherapy. Their mobility extends beyond performing a gantry rotation, but they might encounter obstructions to their motion which limit the gantry angle range. The axial field‐of‐view (FOV) of a reconstructed CBCT image depends on the acquisition geometry. When imaging a large anatomical location, such as the thorax, abdomen, or pelvis, a centered cone beam might be insufficient to acquire untruncated projection images. Some CBCT scanners can laterally displace their detector and collimate the beam to increase the FOV, but the gantry must then perform a rotation to provide complete data for reconstruction.

Purpose

To extend the FOV of a CBCT image with a single short scan (gantry angle range of fan angle) using two complementary short scans.

Methods

We defined an acquisition protocol using two short scans during which the source follows the same trajectory and where the detector has equal and opposite tilt and/or offset between the two scans, which we refer to as complementary scans. We created virtual acquisitions using a Monte Carlo simulator on a digital anthropomorphic phantom and on a computed tomography (CT) scan of a patient abdomen. For our proposed method, each simulation produced two complementary sets of projections, which were weighted for redundancies and used to reconstruct one CBCT image. We compared the resulting images to the ground truth phantoms and simulations of conventional scans.

Results

Reconstruction artifacts were slightly more prominent in the complementary scans w.r.t. a complete scan with untruncated projections but matched those in a single short scan without truncation. When analyzing reconstructed scans from simulated projections with scatter and corrected with prior CT information, we found a global agreement between complementary and conventional scan approaches.

Conclusions

When dealing with a limited range of motion of the gantry of a CBCT scanner, two complementary short scans are a technically valid alternative to a full 360 scan with equal FOV. This approach enables FOV extension without collisions or hardware upgrades.
PDFF‐CNN: An attention‐guided dynamic multi‐orientation feature fusion method for gestational age prediction on imbalanced fetal brain MRI dataset
Authors: Feng Ziteng , Zhou Ran , Xia Wei , Wang Siru , Liu Yang , Huang Zhongwei , Gan Haitao
Published: December 2023

Background

Fetal brain magnetic resonance imaging (MRI)‐based gestational age prediction has been widely used to characterize normal fetal brain development and diagnose congenital brain malformations.

Purpose

The uncertainty of fetal position and external interference leads to variable localization and direction of the fetal brain. In addition, pregnant women typically concentrate on receiving MRI scans during the fetal anomaly scanning week, leading to an imbalanced distribution of fetal brain MRI data. The above‐mentioned problems pose great challenges for deep learning‐based fetal brain MRI gestational age prediction.

Methods

In this study, a pyramid squeeze attention (PSA)‐guided dynamic feature fusion CNN (PDFF‐CNN) is proposed to robustly predict gestational ages from fetal brain MRI images on an imbalanced dataset. PDFF‐CNN contains four components: transformation module, feature extraction module, dynamic feature fusion module, and balanced mean square error (MSE) loss. The transformation and feature extraction modules are employed by using the PSA to learn multiscale and multi‐orientation feature representations in a parallel weight‐sharing Siamese network. The dynamic feature fusion module automatically learns the weights of feature vectors generated in the feature extraction module to dynamically fuse multiscale and multi‐orientation brain sulci and gyri features. Considering the fact of the imbalanced dataset, the balanced MSE loss is used to mitigate the negative impact of imbalanced data distribution on gestational age prediction performance.

Results

Evaluated on an imbalanced fetal brain MRI dataset of 1327 routine clinical T2‐weighted MRI images from 157 subjects, PDFF‐CNN achieved promising gestational age prediction performance with an overall mean absolute error of 0.848 weeks and an of 0.904. Furthermore, the attention activation maps of PDFF‐CNN were derived, which revealed regional features that contributed to gestational age prediction at each gestational stage.

Conclusions

These results suggest that the proposed PDFF‐CNN might have broad clinical applicability in guiding treatment interventions and delivery planning, which has the potential to be helpful with prenatal diagnosis.
Kinetic modeling and parametric imaging of 18F‐PSMA‐11: An evaluation based on total‐body dynamic positron emission tomography scans
Authors: Yuan Hui , Zhang Guojin , Sun Taotao , Ren Jingyun , Zhang Qing , Xiang Zeyin , Liu Entao , Jiang Lei
Published: December 2023

Background

The prostate‐specific membrane antigen (PSMA) targeted positron‐emitting tomography (PET) tracers are increasingly used in clinical practice, with novel tracers constantly being developed. Recently, 18F‐PSMA‐11 has been gaining growing interest for several merits; however, direct in vivo visualization of its kinetic features in humans remains lacking.

Purpose

To visualize the kinetic features of 18F‐PSMA‐11 in healthy subjects and patients with prostate cancer derived from the total‐body dynamic PET scans.

Methods

A total of 8 healthy volunteers (7 males; 1 female) and 3 patients with prostate cancer underwent total‐body PET/CT imaging at 1 and 2 h post injection (p.i.) of 18F‐PSMA‐11, of which 7 healthy subjects and 3 patients underwent total‐body dynamic PET scans lasting 30 min. Reversible two‐tissue compartments (2TC) and Patlak models were fitted based on the voxel‐based time activity curves (TACs), with the parametric images generated subsequently. Additionally, semi‐automated segmentation of multiple organs was performed in the dynamic images to measure the SUVmean at different time points and in the parametric images to estimate the mean value of the kinetic parameters of these organs.

Results

18F‐PSMA‐11 showed quick accumulation within prostate cancer, as early as 45 s after tracer injection. It was rapidly cleared from blood circulation and predominantly excreted through the urinary system. High and rapid radiotracer accumulation was observed in the liver, spleen, lacrimal glands, and salivary glands, whereas gradual accumulation was observed in the skeleton. Prostate cancer tissue is visualized in all parametric images, and best seen in DV and Patlak Ki images. Patlak Ki showed a good correlation with 2TC Ki values (r = 0.858, p < 0.05) but less noise than 2TC images. A scanning time point of 30–35 min p.i. was then suggested for satisfactory tumor to background ratio.

Conclusion

Prostate cancer tissue is visible in most parametric images, and is better shown by Patlak Ki and 2TC DV images. Patlak Ki is consistent with, and thus is preferred over, 2TC Ki images for substantially quicker calculation. Based on the dynamic imaging analysis, a shorter uptake time (30–35 min) might be preferred for a better balance of tumor to background ratio.
Dynamic parametric MRI and deep learning: Unveiling renal pathophysiology through accurate kidney size quantification
Authors: Klein Tobias , Gladytz Thomas , Millward Jason M. , Cantow Kathleen , Hummel Luis , Seeliger Erdmann , Waiczies Sonia , Lippert Christoph , Niendorf Thoralf
Published: December 2023

Renal pathologies often manifest as alterations in kidney size, providing a valuable avenue for employing dynamic parametric MRI as a means to derive kidney size measurements for the diagnosis, treatment, and monitoring of renal disease. Furthermore, this approach holds significant potential in supporting MRI data‐driven preclinical investigations into the intricate mechanisms underlying renal pathophysiology. The integration of deep learning algorithms is crucial in achieving rapid and precise segmentation of the kidney from temporally resolved parametric MRI, facilitating the use of kidney size as a meaningful (pre)clinical biomarker for renal disease. To explore this potential, we employed dynamic parametric T2 mapping of the kidney in rats in conjunction with a custom‐tailored deep dilated U‐Net (DDU‐Net) architecture. The architecture was trained, validated, and tested on manually segmented ground truth kidney data, with benchmarking against an analytical segmentation model and a self‐configuring no new U‐Net. Subsequently, we applied our approach to in vivo longitudinal MRI data, incorporating interventions that emulate clinically relevant scenarios in rats. Our approach achieved high performance metrics, including a Dice coefficient of 0.98, coefficient of determination of 0.92, and a mean absolute percentage error of 1.1% compared with ground truth. The DDU‐Net enabled automated and accurate quantification of acute changes in kidney size, such as aortic occlusion (−8% ± 1%), venous occlusion (5% ± 1%), furosemide administration (2% ± 1%), hypoxemia (−2% ± 1%), and contrast agent‐induced acute kidney injury (11% ± 1%). This approach can potentially be instrumental for the development of dynamic parametric MRI‐based tools for kidney disorders, offering unparalleled insights into renal pathophysiology.
Interest in and barriers to online ESOL instruction for adults during and beyond COVID‐19: Exploring relationships with sociodemographics and English proficiency
Authors: Cox Jessica G. , Chen Lauren Y. , Okatch Harriet
Published: December 2023

Digital divides mean that marginalized groups such as adults who speak English as a second or other language (ESOL) are less likely to have access to online instruction. Higher levels of English proficiency are associated with better health and employment; therefore, access to ESOL classes is essential. We investigated how sociodemographics and English proficiency relate to adult learners' preferences for, and barriers to, online instruction of ESOL during and beyond the COVID‐19 pandemic. Sixty‐one adults completed a survey on their pandemic experiences, demographics, and ESOL classes. Analyses showed nonsignificant relationships between interest in online instruction and internet access, education, income, and age. Respondents reported expecting more nondigital than digital barriers to online instruction overall. Expecting to encounter digital barriers did not constrain respondents' interest in future online instruction; however, beginner‐proficiency individuals had higher interest than those with intermediate or no proficiency. Of the five specific types of remote instruction included in the survey, learning to use new technologies interested most respondents the most. Results will inform ESOL practitioners and administrations as they continue to develop online or digital literacies components for their classes.
PLS3 Mutations in X-Linked Osteoporosis: Clinical and Genetic Features in Five New Families
Authors: Costa Adriana , Martins Andreia , Machado Catarina , Lundberg Elena , Nilsson Ola , Wang Fan , Costantini Alice , Tournis Symeon , Höppner Jakob , Grasemann Corinna , Mäkitie Outi
Published: December 2023

Childhood-onset osteoporosis is a rare but clinically significant condition. Studies have shown pathogenic variants in more than 20 different genes as causative for childhood-onset primary osteoporosis. The X-chromosomal PLS3, encoding Plastin-3, is one of the more recently identified genes. In this study, we describe five new families from four different European countries with PLS3-related skeletal fragility. The index cases were all hemizygous males presenting with long bone and vertebral body compression fractures. All patients had low lumbar spine bone mineral density (BMD). The age at the first clinical fracture ranged from 1.5 to 13 years old. Three of the identified PLS3 variants were stop-gain variants and two were deletions involving either a part or all exons of the gene. In four families the variant was inherited from the mother. All heterozygous women reported here had normal BMD and no bone fractures. Four patients received bisphosphonate treatment with good results, showing a lumbar spine BMD increment and vertebral body reshaping after 10 months to 2 years of treatment. Our findings expand the genetic spectrum of PLS3-related osteoporosis. Our report also shows that early treatment with bisphosphonates may influence the disease course and reduce the progression of osteoporosis, highlighting the importance of early diagnosis for prompt intervention and appropriate genetic counseling.
Monetary policy frameworks since Bretton Woods, across the world and its regions
Authors: Cobham David
Published: December 2023

The Comprehensive Monetary Policy Framework (CMPF) project, which considers de jure and de facto, domestic (money, inflation) and external (exchange rate), monetary policy targets, has now classified 186 countries/currency areas from 1974 to 2017. This means that it is now possible to track the evolution of monetary policy frameworks across the world and its regions. This paper outlines the methodology of the classification and analyses the trends at global, regional and sub-regional levels.
Ammonium Perchlorate-Based Energetic Molecular Perovskite DAP-4 Deposited on CNTs: Catalytic Decomposition Behavior, Mechanisms, and Kinetics
Authors: Ismael Shukri , Yehia M. , Elbasuney Sherif
Published: December 2023

Energetic molecular perovskite with superior decomposition enthalpy and high oxidizing ability is the out coming potential oxidizer in advanced highly energetic systems. In this study, perovskite DAP-4 was fabricated by molecular assembly stagey; multi wall carbon nanotubes (MWCNTs) were employed as a potential catalyst for thermal decomposition of DAP-4. Encapsulation method was adopted to develop DAP-4@MWCNTs nanocomposite. MWCNTs experienced superior catalytic effect on DAP-4 decomposition. MWCNTs offered an increase in DAP-4 decomposition enthalpy by 37.5%, with decrease in its main decomposition temperature by 6 °C. Decomposition kinetics were investigated via isoconversional (model free) and model fitting including Kissinger, Kissinger–Akahira–Sunose (KAS), and integral isoconversional method of Ozawa, Flyn and Wall (FWO). DAP-4@MWCNTs demonstrated apparent activation energy of 135.3 ± 3.9 kJ/mol compared with 142.3 ± 4.15 kJ/mol for pure DAP-4 via KAS model. While DAP-4 demonstrated decomposition reaction of first order reaction model (F1); DAP-4@MWCNTs demonstrated decomposition reaction of third order model (F3). Moreover, a possible catalytic mechanism of MWCNTs via induced holes and electrons to enhance electron transfer ability. This work could promote the application of DAP-4 in the field of solid rocket propellant.
Resection margins, lymph node harvest and 3 year survival in open and laparoscopic colorectal cancer surgery; a prospective cohort study
Authors: De Zoysa M. I. M. , Lokuhetty M. D. S. , Seneviratne S. L.
Published: December 2023

Introduction

Laparoscopic colorectal cancer surgery has been gaining popularity in the last decade. However, there are concerns about adequate lymph node dissection and safe resection margins in laparoscopic colorectal cancer surgery. This study was aimed at comparing the lymph node (LN) clearance and surgical resection margins and 3-year survival for open and laparoscopic colorectal cancer surgery.

Method

A pre-tested interviewer administered questionnaire was used to assess the adoption of the laparoscopic approach by Sri Lankan surgeons. Data was collected prospectively from patients who underwent open or laparoscopic colorectal cancer surgery at the University Surgical Unit of the National Hospital of Sri Lanka from April 2016 to May 2019. The histopathology records were analysed to determine the longitudinal and circumferential resection margins(CRM) and the number of lymph nodes harvested. The resection margins were classified as positive or negative. The total number of LN examined was evaluated. Presence of local recurrence and liver metastasis was determined by contrast enhanced CT scan during 3-years of follow up. Chi square, T test and z test for proportions were used to compare CRM, LN harvest and survival rates between the groups.

Results

Of the surgeons interviewed only 11 (18.4%) performed laparoscopic colorectal cancer surgery. A total of 137 patients (83 males and 54 females) were studied. Eighty-one procedures were laparoscopic and 56 procedures were open. All patients had clear longitudinal resection margins. Seventy-eight patients in the laparoscopic group (96%) and 51 patients (91%) in the open group had clear CRM (p > 0.05). A total of 2188 LNs (mean 15.9) were resected in all procedures. Six-hundred-eighty-nine lymph nodes were removed during open procedures (mean 12.3, SD 0.4) and 1499 (mean 18.5, SD 0.6) were removed during laparoscopy (p < 0.05). At 3 years follow-up the disease-free survival in the laparoscopic and open colon cancer patients was 27/41 (65.8%) and 16/29 (55.1%) respectively (p = 0.35). Disease free survival in the laparoscopic and open rectal cancer patients was 23/38 (60.5%) and 13/25 (52.0%) respectively (p = 0.40). Four patients were lost during follow-up.

Discussion and conclusion

CRM was comparable in the two groups. Laparoscopic group had a significantly higher LN harvest. Three-year survival rates were similar in the two groups. Acceptable results can be obtained with laparoscopic colorectal cancer surgery.
Structural characterization of newly-developed Al79Ni5Fe5Y11 and Al79Ni11Fe5Y5 alloys with amorphous matrixes
Authors: Młynarek-Żak Katarzyna , Dhiman Indu , Matus Krzysztof , Kądziołka-Gaweł Mariola , Łoński Wojciech , Radoń Adrian , Czeppe Tomasz , Babilas Rafał
Published: December 2023

The low glass-forming ability of aluminium-based metallic glasses significantly limits their development and preparation. This paper updates the current state of knowledge by presenting the results of structural studies of two newly-developed Al79Ni5Fe5Y11 and Al79Ni11Fe5Y5 alloys with a reduced aluminium content (< 80 at.%). The alloys were produced by conventional casting (ingots) and melt-spinning (ribbons). Structural characterization was carried out for bulk ingots first, and then for the melt-spun ribbons. The ingots possessed a multiphase crystalline structure, as confirmed by X-ray diffraction and scanning electron microscopy observations. The amorphous structure of the melt-spun ribbons was determined by X-ray diffraction and transmission electron microscopy. SEM observations and EDX element maps of the cross-section of melt-spun ribbons indicated a homogeneous elemental composition. Neutron diffraction revealed the presence of nanocrystals in the amorphous matrix of the melt-spun ribbons. DSC data of the melt-spun ribbons showed exothermic events corresponding to the first crystallization at temperatures of 408 °C and 387 °C for Al79Ni5Fe5Y11 and Al79Ni11Fe5Y5, respectively.
Tumor infiltrating lymphocytes (TILs) are a prognosis biomarker in Colombian patients with triple negative breast cancer
Authors: Huertas-Caro Carlos A. , Ramírez Mayra A. , Rey-Vargas Laura , Bejarano-Rivera Lina María , Ballen Diego Felipe , Nuñez Marcela , Mejía Juan Carlos , Sua-Villegas Luz Fernanda , Cock-Rada Alicia , Zabaleta Jovanny , Fejerman Laura , Sanabria-Salas María Carolina , Serrano-Gomez Silvia J.
Published: December 2023

Triple negative breast cancer (TNBC) is highly immunogenic and high levels of tumor infiltrating lymphocytes (TILs) have been associated with a better prognosis and higher probability to achieve pathological complete response. Here, we explore the potential role of stromal TILs level and composition as a prognostic and predictive biomarker in TNBC. 195 Tumor biospecimens from patients diagnosed with TNBC were included. Stromal TILs (sTILs), positive CD4/CD8 cells were evaluated. Differences in clinic-pathological characteristics according to immune infiltration were assessed. The predictive and prognostic value of immune infiltration was analyzed by multivariate models. Higher immune infiltration was observed in patients with favorable clinical–pathological features. Survival analysis showed that longer overall survival times were observed in patients with a higher infiltration of sTILs (p = 0.00043), CD4 + (p = 0.0074) and CD8 + (p = 0.008). In the multivariate analysis, low levels of sTILs were found to be associated with a higher mortality hazard (HR: 1.59, 95% CI 1.01–2.48). CD4 and CD8 immune infiltration were associated with higher odds for pathological complete response (OR: 1.20, 95% CI 1.00–1.46, OR: 1.28, 1.02–1.65, respectively). Our results suggest that immune infiltration could be used as a prognostic marker for overall survival in TNBC patients.
Identification of CXCL16 as a diagnostic biomarker for obesity and intervertebral disc degeneration based on machine learning
Authors: Liu Jiahao , Zhang Jian , Zhao Xiaokun , Pan Chongzhi , Liu Yuchi , Luo Shengzhong , Miao Xinxin , Wu Tianlong , Cheng Xigao
Published: December 2023

Intervertebral disc degeneration (IDD) is the primary cause of neck and back pain. Obesity has been established as a significant risk factor for IDD. The objective of this study was to explore the molecular mechanisms affecting obesity and IDD by identifying the overlapping crosstalk genes associated with both conditions. The identification of specific diagnostic biomarkers for obesity and IDD would have crucial clinical implications. We obtained gene expression profiles of GSE70362 and GSE152991 from the Gene Expression Omnibus, followed by their analysis using two machine learning algorithms, least absolute shrinkage and selection operator and support vector machine-recursive feature elimination, which enabled the identification of C-X-C motif chemokine ligand 16 (CXCL16) as a shared diagnostic biomarker for obesity and IDD. Additionally, gene set variant analysis was used to explore the potential mechanism of CXCL16 in these diseases, and CXCL16 was found to affect IDD through its effect on fatty acid metabolism. Furthermore, correlation analysis between CXCL16 and immune cells demonstrated that CXCL16 negatively regulated T helper 17 cells to promote IDD. Finally, independent external datasets (GSE124272 and GSE59034) were used to verify the diagnostic efficacy of CXCL16. In conclusion, a common diagnostic biomarker for obesity and IDD, CXCL16, was identified using a machine learning algorithm. This study provides a new perspective for exploring the possible mechanisms by which obesity impacts the development of IDD.
Warming inhibits increases in vegetation net primary productivity despite greening in India
Authors: Das Ripan , Chaturvedi Rajiv Kumar , Roy Adrija , Karmakar Subhankar , Ghosh Subimal
Published: December 2023

India is the second-highest contributor to the post-2000 global greening. However, with satellite data, here we show that this 18.51% increase in Leaf Area Index (LAI) during 2001–2019 fails to translate into increased carbon uptake due to warming constraints. Our analysis further shows 6.19% decrease in Net Primary Productivity (NPP) during 2001–2019 over the temporally consistent forests in India despite 6.75% increase in LAI. We identify hotspots of statistically significant decreasing trends in NPP over the key forested regions of Northeast India, Peninsular India, and the Western Ghats. Together, these areas contribute to more than 31% of the NPP of India (1274.8 TgC.year−1). These three regions are also the warming hotspots in India. Granger Causality analysis confirms that temperature causes the changes in net-photosynthesis of vegetation. Decreasing photosynthesis and stable respiration, above a threshold temperature, over these regions, as seen in observations, are the key reasons behind the declining NPP. Our analysis shows that warming has already started affecting carbon uptake in Indian forests and calls for improved climate resilient forest management practices in a warming world.
Sea level variability and modeling in the Gulf of Guinea using supervised machine learning
Authors: Ayinde Akeem Shola , Yu Huaming , Wu Kejian
Published: December 2023

The rising sea levels due to climate change are a significant concern, particularly for vulnerable, low-lying coastal regions like the Gulf of Guinea (GoG). To effectively address this issue, it is crucial to gain a comprehensive understanding of historical sea level variability, and the influencing factors, and develop a reliable modeling system for future projections. This knowledge is essential for informed planning and mitigation strategies aimed at protecting coastal communities and ecosystems. This study presents a comprehensive analysis of mean sea level anomaly (MSLA) trends in the GoG between 1993 and 2020, covering three distinct periods (1993–2002, 2003–2012, and 2013–2020). It investigates the connections between interannual sea level variability and large-scale oceanic and atmospheric forcings. Furthermore, the study evaluates the performance of supervised machine learning techniques to optimize sea level modeling. The findings reveal a consistent rise in MSLA linear trends across the basin, particularly pronounced in the northern region, with a total linear trend of 88 mm over the entire period. The highest decadal trend (38.7 mm) emerged during 2013–2020, with the most substantial percentage increment (100%) occurring in 2003–2012. Spatial variation in decadal sea-level trends was influenced by subbasin physical forcings. Strong interannual signals in the spatial sea level distribution were identified, linked to large-scale oceanic and atmospheric phenomena. Seasonal variations in sea level trends are attributed to seasonal changes in the forcing factors. The evaluation of supervised learning modeling methods indicates that Random Forest Regression and Gradient Boosting Machines are the most accurate, reproducing interannual sea level patterns in the GoG with 97% and 96% accuracy. These models could be used to derive regional sea level projections via downscaling of climate models. These findings provide essential insights for effective coastal management and climate adaptation strategies in the GoG.
The first use of a photogrammetry drone to estimate population abundance and predict age structure of threatened Sumatran elephants
Authors: Rahman Dede Aulia , Herliansyah Riki , Subhan Beginer , Hutasoit Donal , Imron Muhammad Ali , Kurniawan Didik Bangkit , Sriyanto Teguh , Wijayanto Raden Danang , Fikriansyah Muhammad Hilal , Siregar Ahmad Faisal , Santoso Nyoto
Published: December 2023

Wildlife monitoring in tropical rainforests poses additional challenges due to species often being elusive, cryptic, faintly colored, and preferring concealable, or difficult to access habitats. Unmanned aerial vehicles (UAVs) prove promising for wildlife surveys in different ecosystems in tropical forests and can be crucial in conserving inaccessible biodiverse areas and their associated species. Traditional surveys that involve infiltrating animal habitats could adversely affect the habits and behavior of elusive and cryptic species in response to human presence. Moreover, collecting data through traditional surveys to simultaneously estimate the abundance and demographic rates of communities of species is often prohibitively time-intensive and expensive. This study assesses the scope of drones to non-invasively access the Bukit Tigapuluh Landscape (BTL) in Riau-Jambi, Indonesia, and detect individual elephants of interest. A rotary-wing quadcopter with a vision-based sensor was tested to estimate the elephant population size and age structure. We developed hierarchical modeling and deep learning CNN to estimate elephant abundance and age structure. Drones successfully observed 96 distinct individuals at 8 locations out of 11 sampling areas. We obtained an estimate of the elephant population of 151 individuals (95% CI [124, 179]) within the study area and predicted more adult animals than subadults and juvenile individuals in the population. Our calculations may serve as a vital spark for innovation for future UAV survey designs in large areas with complex topographies while reducing operational effort.
Effects of environmental factors and intraspecific niche overlap on the body and ecological characteristics of red-tongued pit vipers (Gloydius ussuriensis)
Authors: Do Min Seock , Son Seok-Jun , Jung Ji-Hwa , Lee Sang-Cheol , Choi Green , Nam Hyung-Kyu
Published: December 2023

The body condition of a snake species provides important physiological, morphological, and ecological information that elucidates its habits, life cycle, and competitive relationships. We measured the body size and condition of the wild Gloydius ussuriensis population in South Korea from 2018 to 2022, analyzed the degree of intraspecific niche overlap, and identified the geographic and climatic factors affecting their body condition. We found that the females were longer than the males. The body condition index (BCI) of G. ussuriensis differed depending on sex and season; the BCI of the females and males was highest in August and October, respectively. Environmental factors related to altitude and temperature affected the body condition of G. ussuriensis; BCI increased as the mean annual temperature and winter temperature increased; however, it increased when the annual temperature range decreased. The mean Pinaka index was 0.96, indicating a high degree of niche overlap; however, the niche overlap among the neonates was less than that among the adults and juveniles. To elucidate the causes of niche overlap and mechanisms behind the intraspecific competition among G. ussuriensis individuals, the habitat and utilization of food resources at different development stages of G. ussuriensis should be further investigated.
Effects of canagliflozin on cardiac remodeling and hemodynamic parameters in patients with type 2 diabetes mellitus
Authors: Kuo Hsiao-Huai , Lai Yau-Huei , Lin Po-Lin , Chen Hsin-Hao , Hung Chung-Lieh , Liu Lawrence Yu-Min , Yeh Chih-Kuang
Published: December 2023

Sodium-glucose cotransporter type 2 (SGLT2) inhibitors have demonstrated to reduce cardiovascular risk in patients with type 2 diabetes mellitus (T2DM) in large trials independent of glycemic control. The mechanisms of this cardioprotective property remain uncertain. Evidence suggests positive hemodynamic changes and favorable cardiac remodeling contributing to the clinical outcomes but results were conflicting. We aim to investigate the potential impact on hemodynamic parameters, cardiac structure and functions. This prospective observational study included T2DM patients receiving canagliflozin 100 mg per day in addition to their antidiabetic treatment. We analyzed hemodynamic parameters assessed by echocardiographic measurements and impedance cardiography (ICG) to evaluate systolic and diastolic functions from baseline to 24 weeks after treatment. A total of 47 patients (25 males and 22 females) averaging 64.6 ± 10.9 years had a significant reduction in HbA1c, body weight, and systolic blood pressure. Hematocrit increased significantly, while NT-proBNP remained unchanged. E/e′, left atrium (LA) volume, and LA stiffness were reduced, while left ventricle (LV) global longitudinal strain (GLS) and LA strain rates increased at 24 weeks by conventional and speckle tracking echocardiography. LV mass and ejection fraction showed no differences. ICG suggested significant improvement in hemodynamic parameters with increased stroke volume index and cardiac output index and decreased systemic vascular resistance index at 12 and 24 weeks. Canagliflozin improved hemodynamic parameters and had a favorable impact on LA and LV reverse remodeling. These changes may explain the beneficial effect on cardiovascular outcomes in large clinical trials.
Magnetic perovskite nanohybrid based on g-C3N4 nanosheets for photodegradation of toxic environmental pollutants under short-time visible irradiation
Authors: Sharafinia Soheila , Farrokhnia Abdolhadi , Lemraski Ensieh Ghasemian , Rashidi Alimorad
Published: December 2023

In this study, a magnetic perovskite nanohybrid based on g-C3N4 (gCN) nanosheets was synthesized and developed for the efficient photodegradation of toxic environmental pollutants under short-time visible irradiation. The synthesis of this nanohybrid involved the incorporation of SrTiO3:N (STO:N) and ZnFe2O4 (ZnF) onto the g-C3N4 nanosheets through a simple reflux method. Our investigation encompassed a comprehensive suite of analytical techniques, including BET, TGA, TEM, SEM, EDX, DRS, VSM, XRD, photocurrent, and FT-IR, to elucidate the physicochemical characteristics of this nanocomposite in the context of its application in photodegradation processes. The nanohybrid displayed significantly enhanced photocatalytic activity compared to its individual components, achieving a degradation efficiency of over 90% for various pollutants, including organic dyes like Rhodamine B (Rh-B), within a short irradiation time. This enhanced activity can be attributed to the synergistic effect between gCN, STO:N, and ZnF, which promotes the generation of reactive oxygen species and facilitates the degradation process. Notably, the nanocomposite containing 20 wt% STO:N perovskite and 20 wt% ZnF demonstrated the highest Rh-B degradation rate under visible light irradiation within just 30 min. Furthermore, the nanohybrid displayed excellent stability and reusability over seven consecutive runs, retaining its high photocatalytic activity even after multiple cycles of degradation. This remarkable performance can be attributed to the strong interaction between the gCN nanosheets and the magnetic perovskite components, which prevents their aggregation and ensures their efficient utilization. Additionally, the nanohybrid exhibited excellent visible light absorption, enabling the utilization of a wider range of light for degradation. This feature is particularly advantageous, as visible light is more abundant in sunlight compared to UV light, rendering the nanohybrid suitable for practical applications under natural sunlight. In conclusion, the ternary gCN-STO:N@ZnF nanocomposite represents a promising candidate for the treatment of organic pollutants in aqueous environments, offering a versatile and efficient solution.
High frequency oscillations in relation to interictal spikes in predicting postsurgical seizure freedom
Authors: Gerstl Jakob V. E. , Kiseleva Alina , Imbach Lukas , Sarnthein Johannes , Fedele Tommaso
Published: December 2023

We evaluate whether interictal spikes, epileptiform HFOs and their co-occurrence (Spike + HFO) were included in the resection area with respect to seizure outcome. We also characterise the relationship between high frequency oscillations (HFOs) and propagating spikes. We analysed intracranial EEG of 20 patients that underwent resective epilepsy surgery. The co-occurrence of ripples and fast ripples was considered an HFO event; the co-occurrence of an interictal spike and HFO was considered a Spike + HFO event. HFO distribution and spike onset were compared in cases of spike propagation. Accuracy in predicting seizure outcome was 85% for HFO, 60% for Spikes, and 79% for Spike + HFO. Sensitivity was 57% for HFO, 71% for Spikes and 67% for Spikes + HFO. Specificity was 100% for HFO, 54% for Spikes and 85% for Spikes + HFO. In 2/2 patients with spike propagation, the spike onset included the HFO area. Combining interictal spikes with HFO had comparable accuracy to HFO. In patients with propagating spikes, HFO rate was maximal at the onset of spike propagation.
Asymmetric total synthesis of montanine-type amaryllidaceae alkaloids
Authors: Wang Fang , Xu Xiaohan , Yan Yangtian , Zhang Jiayang , Yang Yang
Published: December 2023

The first asymmetric total syntheses of (+)-pancratinines B and C and total syntheses of (−)-montanine, (−)-pancracine and (−)-brunsvigine were realized in a divergent fashion. Our synthetic strategy features a copper-catalyzed [3 + 2] annulation reaction and a Pictet–Spengler cyclization.
Ethanol-assisted room-temperature rapid self-healing polydimethylsiloxane-polyurea/carbon composite elastomers for energy harvesters and smart sensors
Authors: Du Yiming , Wang Hua , Li Xiaofei , Liu Jincheng , Liu Yanyan , Zhang Wei , Liu Qiang , Da Yunsheng , Li Hao , Sun Zhouping , Dong Yong , Tian Xingyou
Published: December 2023

Multiple H-bond networks and unique structures are designed in CCF/PDMS. This CCF/PDMS elastomer simultaneously exhibits excellent tensile, self-healing, and triboelectric properties, promising to be used in energy harvesters and motion sensors, etc.
Distinguishing anti-PEG antibodies by specificity for the PEG terminus using nanoarchitectonics-based antibiofouling cello-oligosaccharide platforms
Authors: Sugiura Kai , Sawada Toshiki , Hata Yuuki , Tanaka Hiroshi , Serizawa Takeshi
Published: December 2023

Anti-PEG antibodies were successfully distinguished by antibiofouling cello-oligosaccharide assemblies tethering specific one-terminal methoxy oligo(ethylene glycol) ligands based on a simple enzyme-linked immunosorbent assay method.
Visualization modality for augmented reality guidance of in‐depth tumour enucleation procedures
Authors: Cattari Nadia , Cutolo Fabrizio , Placa Luciana La , Ferrari Vincenzo
Published: December 2023

Recent research studies reported that the employment of wearable augmented reality (AR) systems such as head‐mounted displays for the in situ visualisation of ultrasound (US) images can improve the outcomes of US‐guided biopsies through reduced procedure completion times and improved accuracy. Here, the authors continue in the direction of recent developments and present the first AR system for guiding an in‐depth tumour enucleation procedure under US guidance. The system features an innovative visualisation modality with cutting trajectories that ‘sink’ into the tissue according to the depth reached by the electric scalpel, tracked in real‐time, and a virtual‐to‐virtual alignment between the scalpel's tip and the trajectory. The system has high accuracy in estimating the scalpel's tip position (mean depth error of 0.4 mm and mean radial error of 1.34 mm). Furthermore, we demonstrated with a preliminary user study that our system allowed us to successfully guide an in‐depth tumour enucleation procedure (i.e. preserving the safety margin around the lesion).
Nonpilot directional protection of a microgrid
Authors: Mohammadhassani Ardavan , Mehrizi‐Sani Ali
Published: December 2023

Protection of an islanded inverter‐based microgrid is challenging because of variable and small fault current contribution of inverter‐based resources (IBR) and the absence of sequence currents. This paper proposes a fast and robust nonpilot directional protection scheme to address this challenge. This scheme relies on support vector machines (SVM) and the harmonic current injection capability of IBRs. Examining the harmonic currents measured by a relay during a fault shows that harmonic currents have similar magnitudes but different orientation under forward and reverse faults. Additionally, harmonic currents have similar orientation but different magnitudes under forward faults at different locations along the protected line. Using this, six SVMs are trained for each relay, given that there are three main types of faults (three‐phase‐to‐ground, line‐to‐line, and line‐to‐ground): three as directional elements and three as zone detection elements. A fault is detected and classified by the undervoltage element of a relay. Then, the measured harmonic currents are routed to the appropriate directionality and zone detection SVMs to facilitate proper relay coordination. The performance of the proposed method is evaluated on the CIGRE North American MV distribution benchmark system under various types of contingency scenarios using PSCAD/EMTDC software.