bluuebunny/crossref_metadata_2025 huggingface dataset:
“It’s called overamping”: experiences of overdose among people who use methamphetamine
Authors: Harding Robert W. , Wagner Katherine T. , Fiuty Phillip , Smith Krysti P. , Page Kimberly , Wagner Karla D.
Published: January 2022

Background

The USA is experiencing increases in methamphetamine use and methamphetamine-related or attributed deaths. In the current study, we explore qualitative narratives of methamphetamine overdose and strategies used by people who use drugs to reduce the undesirable effects associated with methamphetamine use.

Methods

We conducted 21 qualitative interviews with people over the age of 18 who reported using methamphetamine in the previous 3 months in Nevada and New Mexico. Interviews were recorded, transcribed, and analyzed using qualitative thematic analysis.

Results

Respondents described a constellation of psychological and physical symptoms that they characterized as “overamping,” experienced on a continuum from less to more severe. Reports of acute, fatal methamphetamine overdose were rare. Few reported seeking medical attention for undesirable effects (usually related to psychological effects). General self-care strategies such as sleeping and staying hydrated were discussed.

Conclusions

When asked directly, our respondents claimed that acute, fatal methamphetamine overdose is rare or even impossible. However, they described a number of undesirable symptoms associated with overconsumption of methamphetamine and had few clinical or harm reduction strategies at their disposal. Addressing this current wave of drug-related deaths will require attention to the multiple factors that structure experiences of methamphetamine “overdose,” and a collaborative effort with PWUDs to devise effective harm reduction and treatment strategies.
Reducing the stigma surrounding opioid use disorder: evaluating an opioid overdose prevention training program applied to a diverse population
Authors: Bascou Nicholas Alexander , Haslund-Gourley Benjamin , Amber-Monta Katrina , Samson Kyle , Goss Nathaniel , Meredith Dakota , Friedman Andrew , Needleman Andrew , Kumar Vishnu K. , Fischer Bradford D.
Published: January 2022

Background

The opioid epidemic is a rapidly growing public health concern in the USA, as the number of overdose deaths continues to increase each year. One strategy for combating the rising number of overdoses is through opioid overdose prevention programs (OOPPs).

Objective

To evaluate the effectiveness of an innovative OOPP, with changes in knowledge and attitudes serving as the primary outcome measures.

Methods

The OOPP was developed by a group of medical students under guidance from faculty advisors. Training sessions focused on understanding stigmatizing factors of opioid use disorder (OUD), as well as protocols for opioid overdose reversal through naloxone administration. Pre- and post-surveys were partially adapted from the opioid overdose attitudes and knowledge scales and administered to all participants. Paired t-tests were conducted to assess differences between pre- and post-surveys.

Results

A total of 440 individuals participated in the training; 381 completed all or the majority of the survey. Participants came from a diverse set of backgrounds, ages, and experiences. All three knowledge questions showed significant improvements. For attitude questions, significant improvements were found in all three questions evaluating confidence, two of three questions assessing attitudes towards overdose reversal, and four of five questions evaluating stigma and attitudes towards individuals with OUD.

Conclusions

Our innovative OOPP was effective not only in increasing knowledge but also in improving attitudes towards overdose reversal and reducing stigma towards individuals with OUD. Given the strong improvements in attitudes towards those with OUD, efforts should be made to incorporate the unique focus on biopsychosocial and sociohistorical components into future OOPPs.
Comparative effects of EMG-driven robot-assisted therapy versus task-oriented training on motor and daily function in patients with stroke: a randomized cross-over trial
Authors: Chen Yen-Wei , Chiang Wei-Chi , Chang Chia-Ling , Lo Shih-Ming , Wu Ching-Yi
Published: January 2022

Background

Robot-assisted hand training has shown positive effects on promoting neuromuscular control. Since both robot-assisted therapy and task-oriented training are often used in post-stroke rehabilitation, we raised the question of whether two interventions engender differential effects in different domains.

Methods

The study was conducted using a randomized, two-period crossover design. Twenty-four chronic stroke survivors received a 12-session robot-assisted intervention followed by a 12-session task-oriented intervention or vice versa. A 1-month washout period between each intervention was implemented. Outcome measures were evaluated before the intervention, after the first 12-session intervention, and after the second 12-session intervention. Clinical assessments included Fugl-Meyer Assessment for Upper Extremity, Wolf Motor Function Test, Action Research Arm Test and Motor Activity Log.

Results

Our findings suggested that EMG-driven robot-assisted therapy was as effective as task-oriented training in terms of improving upper limbs functional performance in activity domain, and robot-assisted therapy was more effective in improving movement duration during functional tasks. Task-oriented training showed better improvement in body function domain and activity and participation domain, especially in improving spontaneous use of affected arm during daily activities.

Conclusions

Both intervention protocol had their own advantages in different domains, and robot-assisted therapy may save manpower and be considered as an alternative intervention to task-oriented training. Combining the two approaches could yield results greater than either alone, which awaits further study.

Trial registration: ClinicalTrials.gov Identifier: NCT03624153. Registered on 9th August 2018,https://clinicaltrials.gov/ct2/show/NCT03624153.
Cortical reorganization to improve dynamic balance control with error amplification feedback
Authors: Chen Yi-Ching , Tsai Yi-Ying , Chang Gwo-Ching , Hwang Ing-Shiou
Published: January 2022

Background

Error amplification (EA), virtually magnify task errors in visual feedback, is a potential neurocognitive approach to facilitate motor performance. With regional activities and inter-regional connectivity of electroencephalography (EEG), this study investigated underlying cortical mechanisms associated with improvement of postural balance using EA.

Methods

Eighteen healthy young participants maintained postural stability on a stabilometer, guided by two visual feedbacks (error amplification (EA) vs. real error (RE)), while stabilometer plate movement and scalp EEG were recorded. Plate dynamics, including root mean square (RMS), sample entropy (SampEn), and mean frequency (MF) were used to characterize behavioral strategies. Regional cortical activity and inter-regional connectivity of EEG sub-bands were characterized to infer neural control with relative power and phase-lag index (PLI), respectively.

Results

In contrast to RE, EA magnified the errors in the visual feedback to twice its size during stabilometer stance. The results showed that EA led to smaller RMS of postural fluctuations with greater SampEn and MF than RE did. Compared with RE, EA altered cortical organizations with greater regional powers in the mid-frontal cluster (theta, 4–7 Hz), occipital cluster (alpha, 8–12 Hz), and left temporal cluster (beta, 13–35 Hz). In terms of the phase-lag index of EEG between electrode pairs, EA significantly reduced long-range prefrontal-parietal and prefrontal-occipital connectivity of the alpha/beta bands, and the right tempo-parietal connectivity of the theta/alpha bands. Alternatively, EA augmented the fronto-centro-parietal connectivity of the theta/alpha bands, along with the right temporo-frontal and temporo-parietal connectivity of the beta band.

Conclusion

EA alters postural strategies to improve stance stability on a stabilometer with visual feedback, attributable to enhanced error processing and attentional release for target localization. This study provides supporting neural correlates for the use of virtual reality with EA during balance training.
Deep learning approach to estimate foot pressure distribution in walking with application for a cost-effective insole system
Authors: Mun Frederick , Choi Ahnryul
Published: January 2022

Background

Foot pressure distribution can be used as a quantitative parameter for evaluating anatomical deformity of the foot and for diagnosing and treating pathological gait, falling, and pressure sores in diabetes. The objective of this study was to propose a deep learning model that could predict pressure distribution of the whole foot based on information obtained from a small number of pressure sensors in an insole.

Methods

Twenty young and twenty older adults walked a straight pathway at a preferred speed with a Pedar-X system in anti-skid socks. A long short-term memory (LSTM) model was used to predict foot pressure distribution. Pressure values of nine major sensors and the remaining 90 sensors in a Pedar-X system were used as input and output for the model, respectively. The performance of the proposed LSTM structure was compared with that of a traditionally used adaptive neuro-fuzzy interference system (ANFIS). A low-cost insole system consisting of a small number of pressure sensors was fabricated. A gait experiment was additionally performed with five young and five older adults, excluding subjects who were used to construct models. The Pedar-X system placed parallelly on top of the insole prototype developed in this study was in anti-skid socks. Sensor values from a low-cost insole prototype were used as input of the LSTM model. The accuracy of the model was evaluated by applying a leave-one-out cross-validation.

Results

Correlation coefficient and relative root mean square error (RMSE) of the LSTM model were 0.98 (0.92 ~ 0.99) and 7.9 ± 2.3%, respectively, higher than those of the ANFIS model. Additionally, the usefulness of the proposed LSTM model for fabricating a low-cost insole prototype with a small number of sensors was confirmed, showing a correlation coefficient of 0.63 to 0.97 and a relative RMSE of 12.7 ± 7.4%.

Conclusions

This model can be used as an algorithm to develop a low-cost portable smart insole system to monitor age-related physiological and anatomical alterations in foot. This model has the potential to evaluate clinical rehabilitation status of patients with pathological gait, falling, and various foot pathologies when more data of patients with various diseases are accumulated for training.
Initial experience of video-assisted thoracic surgery lobectomy after neoadjuvant chemotherapy plus toripalimab in a patient with locally advanced non-small cell lung cancer: a case report
Authors: Li Wei , Zhai Chunbo , Che Jianpeng , Wang Weiqian , Liu Bingchun
Published: January 2022

Background

Immune checkpoint inhibitors were used for patients with advanced non-small cell lung cancer (NSCLC) more and more frequently and the effects were thrilling. Toripalimab as a new immune checkpoint inhibitor has been shown to be effective in patients with advanced NSCLC. However, data regarding the safety and feasibility of surgical resection after treatment with toripalimab for NSCLC remain scarce. Here, we present a case with locally advanced NSCLC that received video-assisted thoracic surgery (VATS) lobectomy after treatment with toripalimab in combination with chemotherapy.

Case presentation

A 62-year-old male patient with a history of coronary artery stenting operation for two times was found a 3.4 × 3.2 cm cavity mass in the upper lobe of the left lung and enlarged left hilar and mediastinal lymph nodes. Pathological results identified squamous cell carcinoma. The patient was diagnosed with a locally advanced NSCLC and received VATS left upper lobectomy and lymph node dissection after neoadjuvant chemotherapy plus toripalimab for 3 cycles. The postoperative pathological results showed complete tumor remission. Short-term follow-up results were excellent, and long-term results remain to be revealed.

Conclusions

Our preliminary results showed that the use of neoadjuvant toripalimab and chemotherapy for the locally advanced NSCLC before surgical resection is safe and feasible.
Effect of different storage solutions on oxidative stress in human saphenous vein grafts
Authors: Tekin Ilker , Demir Meltem , Özdem Sebahat
Published: January 2022

Background

Ischemia–reperfusion injury of saphenous vein grafts (SVG) during coronary artery bypass grafting surgery negatively impacts endothelial integrity and functionality and is associated with vein graft failure. The aim of this study was to evaluate the level of oxidative stress in human SVG segments following ischemic storage in three intraoperative graft storage solutions: saline (S), autologous heparinized blood (HB) and DuraGraft (DG).

Methods

3 mm tissue rings derived from surplus SVG segments from 50 patients were stored at room temperature for 30 min in DG, S or HB. Total oxidative status (TOS) and total antioxidant status (TAS) levels were determined from which the oxidative stress index (OSI: TOS/TAS ratio) was calculated. A p-value < 0.017 was considered significant implementing a Bonferroni correction.

Results

TOS values were significantly lower for DG stored samples in comparison to both S and HB; there was no difference between S and HB (DG: 32.6 ± 1.8, S: 39.6 ± 2.8 and HB: 40.6 ± 2.4 µmol H2O2 eqv.; DG vs. S and DG vs. HB p < 0.0001, S vs. HB p = 0.047). TAS was higher for both DG and HB in comparison to S (DG: 8.9 ± 0.9, S: 6.9 ± 1.0 and HB: 8.6 ± 0.9 mmol Trolox eqv.; DG vs S p < 0.0001, DG vs. HB p = 0.263, S vs. HB p < 0.0001). OSI differed between all groups with the lowest value for DG (DG: 3.7 ± 0.2, S: 5.8 ± 0.4 and HB: 4.7 ± 0.2 µmol H2O2 eqv./mmol Trolox eqv.; all p < 0.0001).

Conclusions

Saphenous veins grafts stored in DuraGraft had a lower oxidative level, higher antioxidant level and a lower oxidative stress index in comparison to saphenous vein grafts stored in saline or heparinized blood.

ClinicalTrials.gov Identifier NCT02922088.
Left ventricle reverse remodeling in chronic aortic regurgitation patients with dilated ventricle after aortic valve replacement
Authors: Zhang Ming-Kui , Li Li-Na , Xue Hui , Tang Xiu-Jie , Sun He , Wu Qing-Yu
Published: January 2022

Background

Aortic valve replacement (AVR) for chronic aortic regurgitation (AR) with a severe dilated left ventricle and dysfunction leads to left ventricle remodeling. But there are rarely reports on the left ventricle reverse remodeling (LVRR) after AVR. This study aimed to investigate the LVRR and outcomes in chronic AR patients with severe dilated left ventricle and dysfunction after AVR.

Methods

We retrospectively analyzed the clinical datum of chronic aortic regurgitation patients who underwent isolated AVR. The LVRR was defined as an increase in left ventricular ejection fraction (LVEF) at least 10 points or a follow-up LVEF ≥ 50%, and a decrease in the indexed left ventricular end-diastolic diameter of at least 10%, or an indexed left ventricular end-diastolic diameter ≤ 33 mm/m2. The changes in echocardiographic parameters after AVR, survival analysis, the predictors of major adverse cardiac events (MACE), the association between LVRR and MACE were analyzed.

Results

Sixty-nine patients with severe dilated left ventricle and dysfunction underwent isolated AVR. LV remodeling in 54 patients and no LV remodeling in 15 patients at 6–12 months follow-up. The preoperative left ventricular dimensions and volumes were larger, and the EF was lower in the LV no remodeling group than those in the LV remodeling group (all p < 0.05). The adverse LVRR was the predictor for MACE at follow-up. The mean follow-up period was 47.29 months (range 6 to 173 months). The rate of freedom from MACE was 94.44% at 5 years and 92.59% at 10 years in the remodeling group, 60% at 5 years, and 46.67% at 10 years in the no remodeling group.

Conclusions

The left ventricle remodeling after AVR was the important predictor for MACE. LV no remodeling may not be associated with benefits from AVR for chronic aortic regurgitation patients with severe dilated LV and dysfunction.
The full cohort of 512 patients and the nested controlled trial in 93 patients in the Pulmonary Metastasectomy in Colorectal Cancer (PulMiCC) study raise doubts about the effective size at present claimed
Authors: Treasure Tom , Williams Norman R. , Macbeth Fergus
Published: January 2022

A comparison of the relative merits of video-assisted pulmonary metastasectomy versus thoracotomy is predicated on the assumption that removal of asymptomatic lung metastases favourably influences survival and that it does so by a large degree. Recently published but long-awaited evidence from a prospective cohort study and a randomised trial of Pulmonary Metastasectomy in Colorectal Cancer (PulMiCC) challenges that assumption.
Microbial colonization and persistence in deep fractured shales is guided by metabolic exchanges and viral predation
Authors: Amundson Kaela K. , Borton Mikayla A. , Daly Rebecca A. , Hoyt David W. , Wong Allison , Eder Elizabeth , Moore Joseph , Wunch Kenneth , Wrighton Kelly C. , Wilkins Michael J.
Published: January 2022

Background

Microbial colonization of subsurface shales following hydraulic fracturing offers the opportunity to study coupled biotic and abiotic factors that impact microbial persistence in engineered deep subsurface ecosystems. Shale formations underly much of the continental USA and display geographically distinct gradients in temperature and salinity. Complementing studies performed in eastern USA shales that contain brine-like fluids, here we coupled metagenomic and metabolomic approaches to develop the first genome-level insights into ecosystem colonization and microbial community interactions in a lower-salinity, but high-temperature western USA shale formation.

Results

We collected materials used during the hydraulic fracturing process (i.e., chemicals, drill muds) paired with temporal sampling of water produced from three different hydraulically fractured wells in the STACK (SoonerTrendAnadarko Basin,Canadian andKingfisher) shale play in OK, USA. Relative to other shale formations, our metagenomic and metabolomic analyses revealed an expanded taxonomic and metabolic diversity of microorganisms that colonize and persist in fractured shales. Importantly, temporal sampling across all three hydraulic fracturing wells traced the degradation of complex polymers from the hydraulic fracturing process to the production and consumption of organic acids that support sulfate- and thiosulfate-reducing bacteria. Furthermore, we identified 5587 viral genomes and linked many of these to the dominant, colonizing microorganisms, demonstrating the key role that viral predation plays in community dynamics within this closed, engineered system. Lastly, top-side audit sampling of different source materials enabled genome-resolved source tracking, revealing the likely sources of many key colonizing and persisting taxa in these ecosystems.

Conclusions

These findings highlight the importance of resource utilization and resistance to viral predation as key traits that enable specific microbial taxa to persist across fractured shale ecosystems. We also demonstrate the importance of materials used in the hydraulic fracturing process as both a source of persisting shale microorganisms and organic substrates that likely aid in sustaining the microbial community. Moreover, we showed that different physicochemical conditions (i.e., salinity, temperature) can influence the composition and functional potential of persisting microbial communities in shale ecosystems. Together, these results expand our knowledge of microbial life in deep subsurface shales and have important ramifications for management and treatment of microbial biomass in hydraulically fractured wells.
Inferring hydraulic connectivity of induced fractures in the near-wellbore region using distributed acoustic sensing-recorded tube waves excited by perforation shots
Authors: Schumann Harrison , Jin Ge
Published: January 2022

We have developed a novel use of tube waves excited by perforation (or “perf”) shots and recorded on distributed acoustic sensing (DAS) to infer and compare the hydraulic connectivity of induced fractures near the wellbore on a stage-by-stage basis. Evaluating the fracture connectivity near the wellbore is critical because it controls the flow of the hydrocarbons from the formation to the wellbore. Currently, there are no established methods used to assess this property. However, we discuss how tube-wave decay rates can be used to infer relative differences in fracture connectivity between stages and, through field observations on DAS, demonstrate the correlation between decay rates and frac effectiveness. In addition, we consider other potential uses of these data in unconventional wells such as assessing plug integrity and constraining fracture geometry with Krauklis waves. DAS data are commonly acquired during the perf shots but primarily for fiber depth calibration purposes and have not been well studied. Our work illustrates the untapped potential of these data and how it can be easily repurposed to bring new insights about fracture characteristics in the near-wellbore region.
Effective diffraction separation using the improved optimal rank-reduction method
Authors: Lin Peng , Peng Suping , Cui Xiaoqin , Du Wenfeng , Li Chuangjian
Published: January 2022

Seismic diffractions encoding subsurface small-scale geologic structures have great potential for high-resolution imaging of subwavelength information. Diffraction separation from the dominant reflected wavefields still plays a vital role because of the weak energy characteristics of the diffractions. Traditional rank-reduction (RR) methods based on the low-rank assumption of reflection events have been commonly used for diffraction separation. However, these methods using truncated singular-value decomposition (TSVD) suffer from the problem of reflection-rank selection by singular-value spectrum analysis, especially for complicated seismic data. In addition, the separation problem for the tangent wavefields of reflections and diffractions is challenging. To alleviate these limitations, we have developed an effective diffraction separation strategy using an improved optimal RR (ORR) method to remove the dependence on the reflection rank and improve the quality of separation results. The improved RR method adaptively determines the optimal singular values from the input signals by directly solving an optimization problem that minimizes the Frobenius-norm difference between the estimated and exact reflections instead of the TSVD operation. This improved method can effectively overcome the problem of reflection-rank estimation in the global and local RR methods and adjusts to the diversity and complexity of seismic data. The adaptive data-driven algorithms indicate good performance in terms of the trade-off between high-quality diffraction separation and reflection suppression for the ORR operation. Applications of our strategy to synthetic and field examples demonstrate the superiority of diffraction separation in detecting and revealing subsurface small-scale geologic discontinuities and inhomogeneities.
Inversion of low- to medium-frequency velocities and densities from AVO data using invertible neural networks
Authors: Sun Yuhang , Liu Yang , Zhang Mi , Zhang Haoran
Published: January 2022

Amplitude-variation-with-offset (AVO) inversion and neural networks (NN) are widely used to invert elastic parameters. With more constraints from well-log data, neural network-based inversion may estimate elastic parameters with greater precision and resolution than traditional AVO inversion; however, neural network approaches necessitate a massive number of reliable training samples. Furthermore, because the lack of low-frequency information in seismic gathers leads to multiple solutions of the inverse problem, both inversions rely heavily on proper low-frequency initial models. To mitigate the dependence of inversions on accurate training samples and initial models, we have adopted solving inverse problems with the recently developed invertible neural networks (INNs). Unlike conventional neural networks, which address the ambiguous inverse issues directly, INNs learn definite forward modeling and use additional latent variables to increase the uniqueness of solutions. Motivated by the newly developed neural networks, we adopt an INN-based AVO inversion method, which can reliably invert low- to medium-frequency velocities and densities with randomly generated easy-to-access data sets rather than trustworthy training samples or well-prepared initial models. Tests on synthetic and field data indicate that our method is feasible, antinoise capable, and practicable.
Anisotropic modeling with geometric multigrid preconditioned finite-element method
Authors: Sun Qingtao , Zhang Runren , Chen Ke , Feng Naixing , Hu Yunyun
Published: January 2022

Formation anisotropy in complicated geophysical environments can have a significant impact on data interpretation of electromagnetic surveys. To facilitate full 3D modeling of arbitrary anisotropy, we have adopted an [Formula: see text]-version geometric multigrid preconditioned finite-element method (FEM) based on vector basis functions. By using a structured mesh, instead of an unstructured one, our method can conveniently construct the restriction and prolongation operators for multigrid implementation, and then recursively coarsen the grid with the F-cycle coarsening scheme. The geometric multigrid method is used as a preconditioner for the biconjugate-gradient stabilized method to efficiently solve the linear system resulting from the FEM. Our method avoids the need of interpolation for arbitrary anisotropy modeling as in Yee’s grid-based finite-difference method, and it is also more capable of large-scale modeling with respect to the [Formula: see text]-version geometric multigrid preconditioned finite-element method. A numerical example in geophysical well logging is included to demonstrate its numerical performance. Our [Formula: see text]-version geometric multigrid preconditioned FEM is expected to help formation anisotropy characterization with electromagnetic surveys in complicated geophysical environments.
Comparisons of pyrolysis parameters between source rocks and their clay-sized fractions: Implication for source material of hydrocarbon generation
Authors: Zhu Xiaojun , Cai Jingong , Liu Feng , Zhou Qisheng , Zhao Yue , Dong Zhe , Liu Qing , Li Zheng
Published: January 2022

In natural environments, organic-clay interactions are strong and cause organo-clay composites (a combination between organic matter [OM] and clay minerals) to be one of the predominant forms for OM occurrence, and their interactions greatly influence the hydrocarbon (HC) generation of OM within source rocks. However, despite occurring in nature, dominating the OM occurrence, and having unique HC generation ways, organo-clay composites have rarely been investigated as stand-alone petroleum precursors. To improve this understanding, we have compared the Rock-Eval pyrolysis parameters derived from more than 100 source rocks and their corresponding <2 μm clay-sized fractions (representing organo-clay composites). The results show that all of the Rock-Eval pyrolysis parameters in bulk rocks are closely positively correlated with those in their clay-sized fractions, but in clay-sized fractions the quality of OM for HC generation is poorer, in that the pyrolysable organic carbon levels and hydrogen index values are lower, whereas the residual organic carbon levels are higher than those in bulk rocks. Being integrated with the effects of organic-clay interactions on OM occurrence and HC generation, our results suggest that organo-clay composites are stand-alone petroleum precursors for HC generation occurring in source rocks, even if the source rocks exist in great varieties in their attributes. Our source material for HC generation comprehensively integrates the original OM occurrence and HC generation behavior in natural environments, which differs from kerogen and is much closer to the actual source material of HC generation in source rocks, and it calls for further focus on organic-mineral interactions in studies of petroleum systems.
Quantifying the sensitivity of seismic facies classification to seismic attribute selection: An explainable machine-learning study
Authors: Lubo-Robles David , Devegowda Deepak , Jayaram Vikram , Bedle Heather , Marfurt Kurt J. , Pranter Matthew J.
Published: January 2022

During the past two decades, geoscientists have used machine learning (ML) to produce a more quantitative reservoir characterization and discover hidden patterns in their data. However, as the complexity of these models increases, the sensitivity of their results to the choice of the input data becomes more challenging. Measuring how the model uses the input data to perform either a classification or regression task provides an understanding of the data-to-geology relationships which indicates how confident we are in the prediction. To provide such insight, the ML community has developed local interpretable model-agnostic explanations (LIME) and Shapley additive explanations (SHAP) tools. In this study, we train a random forest architecture using a suite of seismic attributes as input to differentiate among mass transport deposits (MTDs), salt, and conformal siliciclastic sediments in a Gulf of Mexico data set. We apply SHAP to understand how the model uses the input seismic attributes to identify target seismic facies and examine in what manner variations in the input, such as adding band-limited random noise or applying a Kuwahara filter, impact the model predictions. During our global analysis, we find that the attribute importance is dynamic, and it changes based on the quality of the seismic attributes and the seismic facies analyzed. For our data volume and target facies, attributes measuring changes in dip and energy show the largest importance for all cases in our sensitivity analysis. We note that to discriminate between the seismic facies, the ML architecture learns a “set of rules” in multiattribute space, and overlap among MTDs, salt, and conformal sediments might exist based on the seismic attribute analyzed. Finally, using SHAP at a voxel scale, we understand why certain areas of interest were misclassified by the algorithm and perform an in-context interpretation to analyze how changes in the geology impacted the model predictions.
Semisupervised salt segmentation using mean teacher
Authors: Geng Zhicheng , Hu Zhanxuan , Wu Xinming , Liang Luming , Fomel Sergey
Published: January 2022

Detecting subsurface salt structures from seismic images is important for seismic structural analysis and subsurface modeling. Recently, deep learning has been successfully applied in solving salt segmentation problems. However, most of the studies focus on supervised salt segmentation and require numerous accurately labeled data, which are usually laborious and time-consuming to collect, especially for the geophysics community. We have adopted a semisupervised framework for salt segmentation, which requires only a small amount of labeled data. In our method, adopting the mean teacher method, we train two models sharing the same network architecture. The student model is optimized using a combination of supervised loss and unsupervised consistency loss, whereas the teacher model is the exponential moving average of the student model. We introduce the unsupervised consistency loss to better extract information from unlabeled data by constraining the network to give consistent predictions for the input data and its perturbed version. We train and test our novel semisupervised method on synthetic and real data sets. Results demonstrate that our semisupervised salt segmentation method outperforms the supervised baseline when there is a lack of labeled training data.
Thoracic Splenosis - A necessary differential diagnosis for pleural based nodules with history of thoracoabdominal trauma
Authors: Mehmood Faisal , Murtaza Muhammad Murad , Ali Shehrbano , Ashraf Amna
Published: January 2022

Thoracic Splenosis (TS) is a rare medical condition, where there is auto-transplantation of the splenic tissue in the thoracic cavity, often leading to pleural based nodules. Our patient is the first ever case of this condition in Pakistan, and underwent extensive diagnostic procedures as well as medical treatments, before receiving the diagnosis of TS. He underwent HRCT for chronic cough that revealed pleural and mediastinal nodules. This coupled with a vague mass in the testes led to the provisional diagnosis of metastasized testicular tumour, and later a diagnosis of pulmonary tuberculosis was made. However, eventually a 99mTc denatured red blood cell scan confirmed the diagnosis of TS. TS is a benign condition, whereas other causes of pleural nodules are relatively malignant, hence its diagnosis is essential in ruling out malignancies. Among the multiple invasive and non-invasive diagnostic modalities, the gold standard remains 99mTc denatured red blood cell scan, which is a sensitive test that provides an accurate diagnosis and bars the need of multiple invasive procedures.

doi: https://doi.org/10.12669/pjms.38.3.4563

How to cite this:Mehmood F, Murtaza MM, Ali S, Ashraf A. Thoracic Splenosis - A necessary differential diagnosis for pleural based nodules with history of thoracoabdominal trauma. Pak J Med Sci. 2022;38(3):---------.  doi: https://doi.org/10.12669/pjms.38.3.4563

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Evaluation of major coronary artery Bifurcation angles with digital angiography: A detailed study of prevalence in the Upper Euphrates Basin
Authors: Deniz Gülnihal , Kavakli Ahmet , Kucukukur Murat , Kose Evren , Karaca Ilgin
Published: January 2022

Objectives: To investigate the diversity and average values of bifurcation angles in a large population to help develop new methods.

Methods: One thousand five individuals (504 females, 501 male) who visited the Cardiology Polyclinic of Fırat University Hospital with the complaint of chest pain between 2010 and 2015 were evaluated retrospectively. Bifurcation angle measurements between LMCA-CX, CX-LAD, LMCA-LAD, CX-OM1, CX-OM2, LAD-D1, LAD-D2, RCA-RMD, RCA-RVD and PDA-PL were evaluated in all cases.

Results: Bifurcation angles between LMCA-LAD, LMCA-Cx and LAD-Cx branches with “> 90 wide angle bifurcations”, and Cx-OM1, Cx-OM2, LAD-D1, LAD-D2, RCA-RMD and PDA-PL with “<70 Y type bifurcation angle” were found to be high in male and female individuals. The RCA-RVD in female individuals was “<70 Y-type bifurcation” in 14 (2.8%) people, “> 70-90 T-type bifurcation” in 209 (41.5%) people, and “> 90 wide angle bifurcation” in 281 (55.8%) people. Results for male subjects were compatible with this. The correlations of all angles were examined. Robust positive correlations (p≤0.001) were found for the angular measurements between the main branches and the side branches (Cx-OM1, Cx-OM2, LAD-D1, LAD-D2 and RCA-RMD, PDA-PL).

Conclusion: With the help of developing technology, we believe that all this coronary angiography data will guide bifurcation stent techniques, which are essential alternatives to bypass.

doi: https://doi.org/10.12669/pjms.38.3.4782

How to cite this:Deniz G, Kavakli A, Kucukukur M, Kose E, Karaca I. Evaluation of major coronary artery Bifurcation angles with digital angiography: A detailed study of prevalence in the Upper Euphrates Basin. Pak J Med Sci. 2022;38(3):---------.  doi: https://doi.org/10.12669/pjms.38.3.4782

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Isolated pericardial cystic Echinococcosis: A rare clinical presentation
Authors: Thapaliya Pratikshya , Ali Taimur Asif , Bhutta Mahwish Mahboob
Published: January 2022

Isolated pericardial Hydatid cyst without involvement of other viscera is a rare condition with reported incidence of 0.5-2% of all cases of cystic echinococcosis even in the countries endemic for the disease. Hydatid disease is a major public health concern in the animal raising regions worldwide. Pericardial hydatid disease can be asymptomatic or present with varying symptoms from atypical chest pain, arrhythmias, rupture and tamponade to anaphylaxis. Early diagnosis and surgical treatment is necessary to prevent fatal complications. Here we report a case of symptomatic isolated pericardial hydatid cyst who presented with epigastric pain.

doi: https://doi.org/10.12669/pjms.38.3.4965

How to cite this:Thapaliya P, Ali TA, Bhutta MM. Isolated pericardial cystic Echinococcosis: A rare clinical presentation. Pak J Med Sci. 2022;38(3):---------. doi: https://doi.org/10.12669/pjms.38.3.4965

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Efficacy of local anaesthetic and steroid combination in prevention of post-herpetic neuralgia: A meta-analysis
Authors: Zhang Xiaolu , Wang Zhiwei , Xian Yiyuan
Published: January 2022

Objective: The objective was to provide synthesized evidence on the efficacy of local anaesthetics and steroid injections for prevention and management of PHN, compared to the standard treatment using anti-viral and analgesic medications. The primary outcomes of interest were incidence of PHN and duration of neuralgic pain.

Methods: Comprehensive searches were done systematically through PubMed, Scopus, Cochrane Central Register of Controlled Trials and Google scholar databases. Randomized controlled trials that compared the efficacy of local anaesthetics and steroid injections for preventing and managing PHN were included for this meta-analysis. A comprehensive search was done for papers published until 15th July 2021.

Results: A total of 10 RCTs were included in the meta-analysis. In the overall pooled analyses, compared to standard care/placebo, those receiving a combination of local anaesthetic and steroid injection had 55% lower risk of PHN at 3 months from onset of rash (RR 0.45; 95% CI, 0.29; 0.70). Out of the different modes of intervention delivery i.e., intravenous, subcutaneous and nerve block, maximum beneficial effect in reducing the incidence of PHN was noted in nerve block (RR 0.55; 95% CI, 0.34, 0.89).

Conclusions: The meta-analysis provides some evidence to support the use of combined local anaesthetic and steroids in reducing risk of post-herpetic neuralgia and duration of neuralgic pain in patients with herpes zoster rash.

doi: https://doi.org/10.12669/pjms.38.3.5140

How to cite this:Zhang X, Wang Z, Xian Y. Efficacy of local anaesthetic and steroid combination in prevention of post-herpetic neuralgia: A meta-analysis. Pak J Med Sci. 2022;38(3):---------. doi: https://doi.org/10.12669/pjms.38.3.5140

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Accuracy of Non-Contrast MRI for the Detection of Hepatocellular Carcinoma: A systematic review and meta-analysis
Authors: Lu Liping , Pan Xuming
Published: January 2022

Non-contrast MRI is used for identifying patients with hepatocellular carcinoma (HCC), especially among high-risk patients with cirrhosis or chronic viral hepatitis. The accuracy of non-contrast MRI has been investigated with varying results. We performed this meta-analysis to consolidate the evidence on the accuracy of non-contrast MRI for the detection of HCC. We conducted a systematic search in the databases of PubMed Central, SCOPUS, MEDLINE, EMBASE and Cochrane from inception till November 2020. We used the STATA software “Midas” package for meta-analysis. We included 15 studies with 3,756 patients. The pooled sensitivity and specificity of non-contrast MRI for HCC detection were 84% (95%CI, 78%-88%) and 94% (95%CI, 91%-97%). The positive likelihood ratio was 14.9 (95% CI, 9.0-24.7) and the negative one 0.17 (0.12-0.23). The overall quality of the studies was high. We found significant heterogeneity based on chi-square test results and I2 statistic > 75%. Deek’s test showed the absence of publication bias. We found that non-contrast MRI has high sensitivity and specificity as a tool for detecting HCC. Studies exploring its accuracy in different ethnic populations are required to strengthen the evidence.

doi: https://doi.org/10.12669/pjms.38.3.5142

How to cite this:Lu L, Pan X. Accuracy of Non-Contrast MRI for the Detection of Hepatocellular Carcinoma: A systematic review and meta-analysis. Pak J Med Sci. 2022;38(3):---------. doi: https://doi.org/10.12669/pjms.38.3.5142

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Ileosigmoid knotting: A review of 923 cases
Authors: Atamanalp Sabri Selcuk , Disci Esra , Peksoz Rifat , Atamanalp Refik Selim , Tatar Atamanalp Cansu
Published: January 2022

Objectives: Ileosigmoid knotting (ISK) is a rare intestinal obstruction form worldwide. The aim of this study was to investigate changing trends in ISK.

Methods: The Web of Science and PubMed databases were electronically searched to find all publications to evaluate all epidemiological, etiological, clinical, laboratory, radiological, therapeutic, and prognostic factors in ISK.

Results: Most of the cases were reported from Asian and African countries. Mean age was 43.9 years with a 79.9%/20.1% of male/female ratio. Main symptom period was 48.1 hours, while the most common clinical features were abdominal pain/tenderness (99.1%), distention (88.3%), and obstipation/constipation (58.8%). Abdominal X-ray radiography, computerized tomography (CT), and magnetic resonance imaging (MRI) were diagnostic in 8.2%, 96.2%, and 100.0%, respectively, while the total diagnostic accuracy rate was 20.8%. Bowels were gangrenous in 85.6% of the patients. Ileum resection was applied in 14.0% of the cases, while sigmoid colon resection in 7.6%, and both segment resection in 67.1%. The mortality rate was 22.7%, while the morbidity rate was also 22.7%.

Conclusion: ISK is a rare disease, but it is still catastrophic despite its two-century recognised past. As an exception, diagnostic convenience arising from CT or MRI looks like the most important change over the last half-century.

doi: https://doi.org/10.12669/pjms.38.3.5320

How to cite this:Atamanalp SS, Disci E, Peksoz R, Atamanalp RS, Tatar Atamanalp C. Ileosigmoid knotting: A review of 923 cases. Pak J Med Sci. 2022;38(3):---------. doi: https://doi.org/10.12669/pjms.38.3.5320

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Attitudes Towards Science: A Study of Gender Differences and Grade Level
Authors: Susilawati Susilawati , Aznam Nurfina , Paidi Paidi
Published: January 2022

It should be noted that learning outcomes are not students’ only achievement; attitude is also the main output in learning. This research explores students’ attitudes toward science learning based on gender and the grade level of schools in Aceh, Indonesia. The participants are 1,023 students from the sixth grade of primary schools and the eighth grade of secondary schools. The total sample includes 16 schools spread across the province. The data have been collected using TOSRA. By using the Likert scale, this questionnaire is useful for obtaining descriptions of the students’ attitudes and assigning scores for a certain group of participants. Based on gender, the results show females reflect more positive attitudes toward science than male students do. According to the grade level of the schools, the data reflect the equality of students’ attitudes toward science between primary and secondary schools. Nevertheless, when primary school students enter secondary school, the majority of students enjoy learning science less. This fact is meaningful feedback for science teachers. This result supports the scholars seeking ways to avoid the gender gap in learning activities. Pedagogical implications are also discussed.
The Development of Historical Thinking Assessment to Examine Students’ Skills in Analyzing the Causality of Historical Events
Authors: Ofianto Ofianto , Aman Aman , Ningsih Tri Zahra , Abidin Nur Fatah
Published: January 2022

This research aimed to develop a historical thinking assessment for students' skills in analyzing the causality of historical events. The development process of Gall and colleagues and Rasch analysis models were used to develop an assessment instrument consisting of two processes, including the analysis of the framework of cause and consequence, the validity, reliability, and difficultness test. This research involved 150 senior high school students, with data collected using the validation sheet, tests, and scoring rubric. The results were in the form of an essay test consisting of six indicators of analyzing cause and consequence. The instruments were valid, reliable, and suitable for assessing students’ skills in analyzing the causality of historical events. The developed instruments were paired with a historical thinking skills assessment to improve the accuracy of the information about students' level of historical thinking skills in the learning history.