bluuebunny/crossref_metadata_2025 huggingface dataset:
Small-artery-mimicking multi-layered 3D co-culture in a self-folding porous graphene-based film
Authors: Sakai Koji , Miura Shigenori , Teshima Tetsuhiko F. , Goto Toichiro , Takeuchi Shoji , Yamaguchi Masumi
Published: September 2023

We co-cultured endothelial and smooth muscle cells in a self-folding porous film to create a vessel-like in vitro model. The tunability of the geometries including curvature and pore size enables us to emulate the geometries of a small artery.
Multicomponent cyclization with azides to synthesize N-heterocycles
Authors: Guo Hong , Zhou Bei , Chang Jingjing , Chang Wenxu , Feng Jiyao , Zhang Zhenhua
Published: September 2023

The review focus on multicomponent reactions of azides for the construction of N-heterocycles in recent 10 years.
Functional characterization of two efficient glycosyltransferases catalysing the formation of rutin from Sophora japonica L.
Authors: Zou Jianlin , Li Hongye , Wang Zilong , Ye Min
Published: September 2023

Two efficient and selective glycosyltransferases were identified from Sophora japonica L.
Surface modulation for highly efficient and stable perovskite solar cells
Authors: Bai Dongliang , Zheng Dexu , Yang Shaoan , Yu Fengyang , Zhu Xuejie , Peng Lei , Wang Likun , Liu Jishuang , Yang Dong , Liu Shengzhong (Frank)
Published: September 2023

As halogen is found to affect both passivation and hydrophobicity ability, a series of ionic organic modulators are designed to contain the halide anions not only to prevent defect formation but also to improve surface tension of the perovskite absorber.
Exploration of nonlinear optical enhancement in acceptor–π–donor indacenodithiophene based derivatives via structural variations: a DFT approach
Authors: Abid Saba , Khalid Muhammad , Sagir Muhammad , Imran Muhammad , Braga Ataualpa A. C. , Chandra Ojha Suvash
Published: September 2023

Herein, a series of indacenodithiophene-based derivatives (TNPD1–TNPD6) were designed having D–π–A architecture via end capped acceptor modulation of a reference molecule (TNPR) to investigate nonlinear optical (NLO) behavior.
A fusion‐attention swin transformer for cardiac MRI image segmentation
Authors: Yang Ruiping , Liu Kun , Liang Yongquan
Published: September 2023

For semantic segmentation of cardiac magnetic resonance image (MRI) with low recognition and high background noise, a fusion‐attention Swin Transformer is proposed based on cognitive science and deep learning methods. It has a U‐shaped symmetric encoding–decoding structure with an attention‐based skip connection. The encoder realizes self‐attention for deep feature representation and the decoder up‐samples global features to the corresponding input resolution for pixel‐level segmentation. By introducing a skip connection between the encoder and decoder based on fusion attention, the remote interaction of global information is realized, and the attention to local features and specific channels is enhanced. A public ACDC cardiac MRI image dataset is used for experiments. The segmentation of the left ventricle, right ventricle, and myocardial layer is realized. The method performs well on a small sample dataset, for example, the pixel accuracy obtained by the proposed model is 93.68%, the Dice coefficient is 92.28%, and HD coefficient is 11.18. Compared with the state‐of‐the‐art models, the segmentation precision has been significantly improved, especially for the low recognition and heavily occluded targets.
Exploring the origins of mega radio halos
Authors: Beduzzi L. , Vazza F. , Brunetti G. , Cuciti V. , Wittor D. , Corsini E. M.
Published: September 2023

We present a first attempt to investigate the origin of radio-emitting electrons in the newly discovered class of mega radio halos in clusters of galaxies. We study the evolution of relativistic electrons accreted by the external regions of a simulated cluster of galaxies at high resolution, including the effect of radiative losses and turbulent reacceleration acting on relativistic electrons. We conclude that turbulent reacceleration induced by structure formation, if sufficiently prolonged, has the potential to produce a large reservoir of radio-emitting electrons in the large regions illuminated by mega radio halos observed by LOFAR.
DES J024008.08-551047.5: A new member of the polar ring galaxy family
Authors: Akhil Krishna R. , Kartha Sreeja S. , Mathew Blesson , Ujjwal Krishnan , Ezhikode Savithri H. , Robin Thomas
Published: September 2023

Aims. This study presents the discovery of a new polar ring galaxy (PRG) candidate and highlights its unique features and characteristics. We provide evidence from photometric analysis that supports the inclusion of galaxy DES J024008.08-551047.5 (DJ0240) in the PRG catalogue.

Methods. During the visual observations of optical imaging data obtained from the Dark Energy Camera Legacy Survey, a serendipitous discovery was made of a ringed galaxy, DJ0240. We conducted a one-dimensional isophotal analysis to determine the position angle of the ring component and its relative orientation to the host galaxy. A two-dimensional GALFIT analysis was performed to confirm the orthogonal nature of the ring galaxy and identify distinct components within the host galaxy. We compared the photometric properties of the host and ring components of DJ0240 with PRGs and other ring-type galaxies (RTGs), finding that DJ0240 shares similar properties with both of these galaxy types.

Results. We have discovered the galaxy DJ0240, a PRG candidate with a ring component positioned almost perpendicular to the host galaxy. The position angles of the ring and host components are ∼80° and ∼10°, respectively, indicating that they are nearly orthogonal to each other. The extension of the ring component is three times greater than that of the host galaxy and shows a distinct colour separation, being bluer than the host. The estimated g − r colour values of the host and ring components are 0.86 ± 0.02 and 0.59 ± 0.10 mag, respectively. The colour value of the ring component is similar to those of typical spiral galaxies. The host galaxy’s colour and the presence of a bulge and disc components indicate that the host galaxy may be lenticular. Our findings reveal a subtle yet noticeable colour difference between the host and ring components of PRGs and RTGs. We observe that both the host and ring components of DJ0240 align more closely with PRGs than with RTGs. Furthermore, we compared the Sersic index values of the ring component (nring) of galaxy DJ0240 with a selected sample of PRGs and Hoag-type galaxies. The results show that DJ0240 has a remarkably low nring value of 0.13, supporting the galaxy’s classification as a PRG. Hence, we suggest that the ring galaxy DJ0240 is a highly promising candidate for inclusion in the family of PRGs.
Use of Steroids in Diagnostic Confusion between Intestinal Tuberculosis and Crohn's Disease: A Brief Experience
Authors: Panigrahi Manas Kumar , Kumar Chandan
Published: September 2023

Background Differentiating intestinal tuberculosis (TB) from Crohn's disease (CD) is challenging. Even after complete workup, the underlying diagnosis can often remain unclear. Traditionally, trial of antitubercular therapy (ATT) is resorted to in such situations, but the use of ATT could increase stricturing complications in CD.

Methods We report findings from our cohort of patients with ileocecal ulcers. Among patients with a diagnostic confusion between intestinal TB and CD, steroids were started in an in-hospital setting under close observation. We report a brief series of patients with a close overlap in terms of disease presentation, behavior, laboratory, and histopathological findings. All the cases had skip lesions in the colon with inconclusive final diagnosis. We attempted to differentiate between the two by a short trial of steroids for 2 weeks.

Results Of the 30 patients with ileocecal ulceration, the diagnosis remained uncertain between intestinal TB and CD in three patients. All three patients received steroids for 2 weeks. Eventually, all were diagnosed to have TB. Administration of steroids helped increase microbiological yield with all three having a positive microbiological diagnosis at 2 weeks. However, one patient developed dissemination (pulmonary lesions).

Conclusion With a definitive risk of flare of TB with steroid, we encountered a positive diagnosis with repeat colonoscopy biopsy, positive result in bronchoalveolar lavage, and in third case positive report of cartridge-based nucleotide acid amplification test on repeat colonoscopy biopsy. In cases where differentiation of ileocecal TB from CD is not possible confidently, using a steroid-first approach increases the microbiological yield with a potential risk of dissemination.
Tuberculosis is a Common Cause of Post-Liver Transplant Ascites: An Observational Study
Authors: R. Sowmya T. , Kulkarni Anand V. , Sharma Mithun , Reddy Raghuram , Menon Balachandran P. , Reddy Nageshwar , Rao Padaki Nagaraja
Published: September 2023

Background Ascites is expected to resolve within 2 to 4 weeks following orthotopic liver transplantation. New-onset ascites after transplant is associated increased morbidity and affects quality of life. The risk of opportunistic infections is high in transplant recipients due to immunosuppressive drugs.

Objective The objective was to assess the incidence of new-onset ascites in the transplant recipients and describe the cause and course of the same.

Methods We retrospectively collected data of all the patients who underwent liver transplantation at our center from April 1, 2020 to April 1, 2021. The details of patients developing ascites post-liver transplantation were retrieved. The patients were followed up for 1 year after transplant.

Results A total of 95 patients underwent living donor liver transplantation at our center. The incidence of new-onset ascites was 8.42% (8/95). Six out eight patients were diagnosed with tubercular ascites of whom one had disseminated tuberculosis. None of the patients had concomitant pulmonary tuberculosis. Ascites secondary to hypoalbuminemia was reported in two patients. Immunoglobulin A nephropathy and tacrolimus therapy were the underlying causes of proteinuria.

Conclusion Tuberculosis was the leading cause of ascites in post-transplant period in our study. Tuberculosis should be considered as a differential diagnosis while evaluating these patients especially in the Asia-Pacific region. Being a potentially curable cause, timely diagnosis and treatment significantly improves graft survival.
Sofosbuvir-Velpatasvir Full Dose in Chronic Hepatitis C in End-Stage Renal Disease: An Observational Study from a Himalayan Region
Authors: Ashraf Aadil , Shah Altaf , Wani Muzafar , Khan Mushtaq , Gulzar G.M. , Parveen Shaheena , Singh Jaswinder , Dar Hilal , Ahmad Nadeem
Published: September 2023

Background Treatment of chronic hepatitis C (CHC) in the setting of chronic kidney disease and end-stage renal disease (ESRD) is challenging.

Objectives We planned to evaluate the efficacy and safety of full dose of combination of sofosbuvir-velpatasvir in the treatment of CHC in patients with ESRD or those on maintenance hemodialysis.

Methods The prospective observational study was conducted in a tertiary care center in North India where all patients with chronic kidney disease (CKD) were assessed. Those with hepatitis C virus (HCV) antibody positivity underwent testing for HCV ribonucleic acid and were treated if eligible. Full dose of sofosbuvir-velpatasvir was administered daily for 12 weeks (or 24 weeks for decompensated liver disease).

Results Of the 162 patients (mean age: 43.08 ± 12.08 years, 114 males), 125 were on regular hemodialysis. Twenty-four (15%) had evidence of liver cirrhosis, out of which four patients had evidence of decompensation. One hundred forty-two patients (87.6%) had an early virological response. Most patients, 160 (98.7%), obtained end of therapy viral clearance and sustained virological response at 12 weeks after therapy. Two patients died, and rest of the patients completed therapy. The adverse effects noticed were nausea (20%), vomiting (18%), headache (10%), and weakness (7%).

Conclusion A combination of sofosbuvir and velpatasvir is effective and safe in treating CHC in the setting of CKD.
Review: Modern Management of Liver Abscess
Authors: Wadhera Sarthak , Arora Navneet , Dhibar Deba Prasad
Published: September 2023

An encapsulated collection of suppurated material within the liver is termed a liver abscess, which may be caused due to bacterial, parasitic, or fungal infection. Liver abscesses can be divided into infectious, iatrogenic, and malignant. Infection spreading through the biliary tract is the most common cause now. Escherichia coli, the most common organism causing liver abscess two decades ago, is replaced by Klebsiella pneumonia, accounting for 50 to 70% of cases in the Asian subcontinent; however, liver abscesses due to Entameba histolytica are also found quiet often in day to day clinical practice. Risk factors associated with the development of liver abscess are increasing age, male sex, presence of underlying diabetes mellitus, liver cirrhosis, continuous use of proton pump inhibitors, and immunocompromised state. Fever and abdominal pain are the typical clinical symptoms of a liver abscess. Other common symptoms include nausea, vomiting, malaise, and chills. Tachycardia, right upper quadrant tenderness, and hepatomegaly are common examination findings. USG of the abdomen is performed in all suspected cases of liver abscess and has a sensitivity of 85%. Small abscesses, less than 3 to 4 cm, can be managed with antibiotics. Percutaneous drainage can be done either by single-time needle aspiration or catheter drainage.
Computational Fluid Dynamics Analysis of Trigeminal Neuralgia Associated with the Vertebral Artery: A Report of Two Cases
Authors: Patil Kapil , Komatsu Fuminari , Tanaka Riki , Sasaki Kento , Yamada Yasuhiro , Okubo Mai , Katayama Tomoka , Miyatani Kyosuke , Chemate Sachin , Satoh Toru , Kato Yoko
Published: September 2023

Trigeminal neuralgia is a nerve disorder that causes unilateral severe facial pain. The clinical features of trigeminal neuralgia are agonizing, paroxysmal, anticipated in one or more divisions of the trigeminal nerve, with repetitive bursts of a few seconds, exacerbated by cutaneous stimuli. Microvascular decompression is proven effective, resulting in a positive outcome. Here, we report two cases of trigeminal neuralgia associated with the vertebral artery, who underwent endoscopic microvascular decompression. This case report aims to show the benefit of computational fluid dynamics evaluation of the neurovascular contact and its effect on change in wall shear stress magnitude of the offending vertebral artery after surgical management with microvascular decompression.
Systemic Review: Neurological Deficits following Ventriculoperitoneal Shunt (VPS) Insertion
Authors: Moshref Rana , Algethmi Rafaa Ahmed
Published: September 2023

A reduction in fluid absorption or an obstruction of normal outflow is a common cause of hydrocephalus. It typically requires medical attention, which frequently entails the placement of a ventriculoperitoneal shunt (VPS) to lower intracranial pressure. We intend to list the few, documented examples of neurological impairments resulting from the installation of a VPS in this systematic study. Two search engines (PubMed and Cochrane) were used to conduct a systematic review from 1975 to December 12, 2021. The following search terms were employed: neurological deficits or neurological injury or palsies or thalamus or tract or longitudinal fasciculus or somatotropy or fasciculus or hearing loss or hemisensory or cortico AND ventriculoperitoneal shunt or VPS AND hydrocephalus. The inclusion criteria included VPS, neurological deficits, and human participants. The exclusion criteria included ventriculoarterial shunt, lumboperitoneal shunt, nonhuman subjects, and infection. Twenty trials in total, including a total of 25 patients, were included. There were 17 case report studies. A total of 35/785 patients (4.46%) experienced neurological impairments. In 9/25 (36%) of shunt cases had one of the three recognized causes: trapped fourth ventricle, dandy walker, or syringomyelia. Most of the patients developed VI, VII nerve palsies 11/25 (44%) followed by weakness, cerebellar symptoms, and VI nerve palsy. The brainstem was seen to be the most often injured structure (15/25; 60%), followed by deep brain structures (thalamus, basal ganglia, and white matter tracts; 20%). Even though ventriculoperitoneal shunting is a routine and straightforward treatment, issues can still arise. Although rare, there have been reports of cranial nerve impairments, therefore care should be taken.
Treatment of Idiopathic Normal Pressure Hydrocephalus with a Novel Programmable Valve: Prospective Evaluation of Costs, Efficacy, and Safety
Authors: Reis Rodolfo Casimiro , Yamashita Renata Harumi Gobbato , Solla Davi Jorge Fontoura , Ramin Laís Fajardo , Teixeira Manoel Jacobsen , Pinto Fernando Campos Gomes
Published: September 2023

Objective Programmable valves provide an equal or superior neurological outcome when compared with fixed pressure ones, with fewer complications, in treating idiopathic normal pressure hydrocephalus (iNPH) patients. Long-term costs of these treatments have not been properly compared in literature. We sought to compare costs, efficacy, and safety of 1-year treatment of iNPH patients with programmable valve Sphera Pro and a fixed pressure valve.

Materials and Methods A prospective cohort of iNPH patients treated with programmable valve was compared with a historical cohort of iNPH patients treated with fixed pressure valve. Our primary outcome was mean direct cost of treating iNPH up to 1 year. Efficacy in treating iNPH and safety were assessed as secondary outcomes.

Statistical Analysis Proportions were compared using chi-square or Fisher's exact tests. Normally distributed variables were compared using the Student's t-test or the Mann–Whitney's U test. Differences in the evolution of the variables over time were assessed using generalized estimating equations. All tests were two-sided, with an α of 0.05.

Results A total of 19 patients were analyzed in each group (mean age 75 years, the majority male). Comorbidities and clinical presentation were similar between groups. Both fixed pressure and programmable valve patients had neurological improvement over time (p < 0.001), but no difference was seen between groups (p = 0.104). The fixed pressure valve group had more complications than the programmable valve group (52.6% vs. 10.5%, respectively, p = 0.013). Annual treatment cost per patient was US$ 3,820 ± 2,231 in the fixed pressure valve group and US$ 3,108 ± 553 in the programmable valve group. Mean difference was US$712 (95% confidence interval, 393–1,805) in favor of the programmable valve group.

Conclusion The Sphera Pro valve with gravitational unit had 1 year treatment cost not higher than that of fixed pressure valve, and resulted in similar efficacy and fewer complications.
Evaluation of cyclooxygenase-2, P53, vascular endothelial growth factor, and nitric oxide synthase-2 in angiogenesis and growth of tobacco-related malignancies
Authors: Gautam Shruti , Sangma Manisha , Rana Safia , Khetrapal Shaan , Kapur Sujala , Jairajpuri Zeeba S.
Published: September 2023

Objectives:

In India, tobacco consumption is responsible for half of all the cancers in men and a quarter in women. The present study focuses on the expression of cyclooxygenase-2 (COX-2), P53, vascular endothelial growth factor (VEGF), and nitric oxide synthase (NOS) and their relationship with the growth and angiogenesis of tobacco-related malignancies of the oral cavity, esophagus, lungs, and stomach. It further evaluates the carcinogenic action of nicotine and examines whether COX-2 and NOS-2 overexpression is responsible for tumor growth and associated angiogenic VEGF expression via its receptor.

Materials and Methods:

A cross-sectional study on 140 biopsies, resected specimens of cancer of oral cavity, esophagus, stomach, and lungs, was done. Immunohistochemical evaluation for p53, COX-2, VEGF, and inducible NOS was done. Relevant statistical analysis was applied for the significance of the findings.

Statistical Analysis:

Relevant statistical analysis was done using SPSS, chi-square and Fisher's exact tests were applied for the significance of the findings. A p-value of < 0.05 was considered as significant value.

Results:

Immunohistochemical evaluation of pattern of expression of COX-2, NOS-2, VEGF, and p53 was done in both tobacco- and nontobacco-associated cases. The results of the present study revealed an upregulation of COX-2, NOS-2, VEGF, and p53 in all the malignancies.

Conclusion:

The present results indicated that p53 protein accumulation and increased expression of COX-2, NOS-2, and VEGF might be responsible for carcinogenesis and tumor aggressiveness by enhancing angiogenesis. A possible significant effect of nicotine on COX-2 and P53 expression in tumorigenesis is revealed. These data might have important implications for the therapeutic use of COX-2, NOS-2, and VEGF inhibitors as well as of p53 gene therapy in future anticancer therapeutic strategies in tobacco-related malignancies.
A Case Report and Review of Literature: Epithelioid Hemangioendothelioma—An Uncommon Challenging Case
Authors: Soni Sweta , Devnani Bharti , Elhence Poonam , Soni Kapil , Vedant Deepak , Gupta Palak , Pareek Puneet , Vyas Rakesh Kumar
Published: September 2023

Introduction Epithelioid hemangioendothelioma (EHE) is a rare vascular tumor of soft tissue and bone that may uncommonly occur in the liver, lung, and head and neck region. EHEs have a higher predilection for recurrence at the local site as well as distant metastasis. Surgical excision is important and is the treatment in localized diseases. A decision to give adjuvant radiotherapy should be subjective and may differ on case-to-case basis. Limited studies are available exploring the role of targeted or systemic therapy.

Case Presentation A 56-year-old lady represented with right-sided submandibular region EHE with bilateral lung metastasis. The patient underwent surgery and radiotherapy followed by targeted therapy tab pazopanib for systemic control. At 2 years of follow-up, positron emission tomography-computed tomography showed local regional control and stable systemic diseases.

Conclusion The uncertainty in choosing the most suitable treatment of EHE patients is high and may result in dissatisfactory outcomes among several patients. The present case study identified a treatment dilemma making management more challenging for rare EHE with mandibular involvement.
Simulation of localized electron density enhancement caused by high-pressure H2O gas release in ionosphere
Authors: Liang Yonggan , Tian Ruihuan , Xu Bin , Jiang Xiaonan , Yang Jutao , Wu Jian , Feng Jie , Li Hui , Hao Shuji , Ma Zhengzheng
Published: September 2023

Based on the continuity and momentum equations, a self-consistent simulation model is developed for describing the localized electron density enhancement caused by high-pressure H2O gas release in the ionosphere. The chemical reaction and momentum exchange process between the neutral gas and ionospheric plasma species are considered in the theoretical simulation model. The finite element method is used to solve the simulation model for H2O gas release, and the expansion and ionospheric disturbance process at the early stage of high-pressure gas release are studied. It is shown that the space expansion of the released gas is mainly dominated by the pressure difference between the H2O gas and the ionospheric plasma at the early stage of release. Then the diffusion process becomes the dominant process of the space transport of H2O molecules. An electron depletion region forms near the center of the release region due to the chemical reaction and collision process with H2O molecules. Meanwhile, an electron density enhancement region forms on both sides along the magnetic field direction due to the electron snowplow effect. With the increase in the released mass of H2O gas, the intensity and duration of the electron density enhancement increase gradually. With the release position rising, it is found that the intensity of the electron density enhancement has a peak near 380 km and the duration increases slightly with the increasing release height.
Design of an ultra-wideband solar absorber based on tungsten
Authors: Wang Yunji , Liu Fei , Ni Bo , Chen Lin , Ji Ke
Published: September 2023

A solar absorber based on tungsten with an ultra-wide wavelength band is investigated numerically using the finite-difference time–domain method. The designed structure consists of a cross-shaped resonator on top of the absorber and a metal thin film on the bottom that are separated by an intermediate dielectric layer. The absorber demonstrates continuous high absorptivity (>90%) over the 514–1945 nm wavelength range, and the average absorptivity ranges up to 92.36% within the 200–2000 nm range. The excitation of propagating surface plasmon resonance (SPR) and localized SPR in combination with Fabry–Pérot resonance leads to the observed wideband absorption. We also demonstrate that the proposed absorber is insensitive to both transverse electric and transverse magnetic polarizations and study its absorptive performance at larger angles of incidence. The effects of the structural parameters and of different dielectric layer materials on the absorption performance have also been investigated. Furthermore, we explain the absorption mechanism using a power flow plot and impedance matching. The proposed absorber has promising prospects for applications, including solar cells, solar energy harvesting, and thermal emitters.
The COVID-19 pandemic and changing meanings of flatten the curve
Authors: Kang Ji-in , Kwon Iksoo
Published: September 2023

This paper conducts a comparative analysis of the meanings of the phrase flatten the curve before and after the outbreak of the COVID-19 pandemic. Using data from two corpora, the iWeb Corpus and the Coronavirus Corpus, it focuses on semantic frames (Fillmore, 1985) and frame metonymy (Dancygier & Sweetser, 2014). The investigation reveals that the construal of the phrase after the outbreak of COVID-19 requires the invocation of both bell curve and pandemic frames; that is, without the pandemic frame, the phrase would remain in the domain of statistics and refer to a change in a graph. The data are sorted into four semantic categories based on the context in which they appear (epidemiological/non-epidemiological) and on the effect they pursue regarding the flattening-the-curve scenario (rigorous/non-rigorous). The phrase’s polysemy is explained by the part of the process for effect of the process metonymy. The flatter curve, as a salient part of a scenario, serves to refer to one of the scenario’s effects. The analysis also observes a correlation between the real-world experience of the pandemic and the actual frequency of flatten the curve in that the ratio of each semantic category reflects the contemporaneous real-world significance of reducing the rate of increase of new infections.
Cardiomyocyte ryanodine receptor clusters expand and coalesce after application of isoproterenol
Authors: Scriven David R.L. , Johnsen Anne Berit , Asghari Parisa , Chou Keng C. , Moore Edwin D.W.
Published: September 2023

Earlier work has shown that ventricular ryanodine receptors (RyR2) within a cluster rearrange on phosphorylation as well as with a number of other stimuli. Using dSTORM, we investigated the effects of 300 nmol/liter isoproterenol on RyR2 clusters. In rat ventricular cardiomyocytes, there was a symmetrical enlargement of RyR2 cluster areas, a decrease in the edge-to-edge nearest neighbor distance, and distribution changes that suggested movement to increase the cluster areas by coalescence. The surface area covered by the phosphorylated clusters was significantly greater than in the control cells, as was the cluster density. This latter change was accompanied by a decreased cluster fragmentation, implying that new tetramers were brought into the sarcoplasmic reticulum. We propose a possible mechanism to explain these changes. We also visualized individual RyR2 tetramers and confirmed our earlier electron-tomographic finding that the tetramers are in a disorganized but non-random array occupying about half of the cluster area. Multiclusters, cluster groups defined by the maximum distance between their members, were analyzed for various distances. At 100 nm, the areas occupied by the multiclusters just exceeded those of the single clusters, and more than half of the multiclusters had only a single subcluster that could initiate a spark. Phosphorylation increased the size of the multiclusters, markedly so for distances >100 nm. There was no relationship between the number of subclusters in a group and the area covered by it. We conclude that isoproterenol induces rapid, significant, changes in the molecular architecture of excitation–contraction coupling.
Towards the establishment of national diagnostic reference levels for chest x-ray examinations in Sri Lanka: a multi-centric study
Authors: Welarathna Sachith , Velautham Sivakumar , Sarasanandarajah Sivananthan
Published: September 2023

The establishment of diagnostic reference levels (DRLs) is an effective tool for optimising radiation doses delivered to patients during medical imaging procedures. This study aimed to compare the institutional DRLs (IDRLs) and propose a multi-centric diagnostic reference level (MCDRL) for chest x-ray examinations in adult patients in Sri Lanka. A prospective cross-sectional study was conducted with 1091 adult patients across six major tertiary care hospitals. Data on patient characteristics, such as age, sex, weight, and body mass index, and exposure parameters, such as tube voltage (kVp) and the product of tube current and exposure time (mAs), were collected. Patient doses were measured in terms of kerma-area product (PKA) using a PKA meter mounted on the collimator of the x-ray tube. IDRLs were computed for each hospital according to the International Commission on Radiological Protection guidelines, and the 75th percentile PKA was used to propose the MCDRL. The relationship between patient weight and exposure parameters was examined using Spearman’s rank correlation to investigate the radiographic practice among hospitals. Results showed that IDRLs varied from 0.10 to 0.26 Gy cm2. The proposed MCDRL was 0.23 Gy cm2, substantially higher than the recently published DRLs from other countries. The median kVp ranged from 95 to 104, while mAs ranged from 2.5 to 5.6. Large variations in the PKA and exposure parameters were observed within and among hospitals. The elevated PKA values observed in this study were mostly due to the use of high mAs in clinical practice. The weak correlation observed between patient weight and exposure parameters suggests the need to standardise examination protocols concerning patient size. The observed dose variations demonstrate the need for the establishment of national DRLs. Until then, the proposed MCDRL can be considered as the benchmark dose level for chest x-ray examinations in Sri Lanka.
Evolution of Subkilometer-scale Impact Craters on the Lunar Maria as Constrained from Mini-RF Data and Topographic Degradation Model
Authors: Sun 孙 Qinghai 庆海 , Fa 法 Wenzhe 文哲 , Zhu 祝 Meng-Hua 梦华 , Du 都 Jun 骏
Published: September 2023

Physical properties (e.g., ejecta size and distribution) of impact craters are crucial and essential to understanding the ejecta excavation and deposition process, estimating rock breakdown rate, and revealing their evolution characteristics. However, whether these physical properties are scale-dependent and how they evolve in different radial regions needs further studies. In this study, we first investigated the physical properties and evolution of sub-kilometer (D ≤ 800 m) craters on lunar maria based on the radar circular polarization ratio (CPR). In addition, we estimated the periods over which rocks and blocky ejecta are exposed and buried in the shallow subsurface layer (termed as exposure time) in different radial regions and assessed the retention time and degradation states for potential radar anomalous craters. We found that in the central region of craters, the largest median CPR occurs after an 80 Myr delay following crater formation. In the rim region, there is no obvious CPR peak in the first 100 Ma, whereas in the upper wall region, an evident CPR peak occurs beyond 100 Ma and could last over one billion years. In addition, the probable exposure time of rocks and blocky ejecta is estimated to be ∼2.0 Gyr (central region), ∼2.7 Gyr (upper wall region), ∼2.1 Gyr (rim region), and ∼0.6 Gyr (continuous ejecta blanket region). We also propose that the retention time of radar anomalous craters depends on the crater size, whereas their degraded states are independent of crater size.
Saturated Fluid Variation Effect on Seismic Anisotropy: A Case Study of Deep-Water Reservoir
Authors: Oktariena Madaniya , Triyoso W , Fatkhan  , Sukmono S , Ambarsari D S , Septama E , Wardaya P D
Published: September 2023

Many factors can drive seismic anisotropy, whether it is the intrinsic condition of rock, external force, or longwave anisotropy. Saturated fluid, as one of the reservoir’s intrinsic elements, is known to trigger an anisotropic effect in far offset seismic with Vertical Transverse Isotropic character. Anisotropy on seismic presents as hockey stick curving that a combination of two-parameter could correct during move-out: V
NMO
and the elliptical anisotropy η parameter. This research means observing how the saturated fluid within the reservoir contributes to the observed anisotropy in seismic. Rock physics modelling (RPM) and fluid substitution (FRM) are conducted to investigate the saturated fluid effect at a particular temperature and pressure that reflects the deep-water environment. The anisotropy parameter is extracted by applying Tsvankin 4th Order NMO to obtain the elliptical anisotropy η parameter. Based on synthetic seismic modelling with VTI Rüger Reflectivity, saturated fluid has an effect on far offset seismic as a manifestation of seismic anisotropy η. In this case of a deep-water environment, gas saturated sand needs the most considerable η correction, followed by oil and water-saturated. Although the η value difference is relatively small and easily dismissed as insignificant, saturated fluid indeed does contribute to the observed seismic anisotropy.
Identification of the Groundwater Layer using the Resistivity Method of the Schlumberger Configuration in the Bumi Harapan Village Area
Authors: Saputra F , Arisalwadi M , Rahmania  , Sastrawan F D
Published: September 2023

This research applied the geoelectric method to determine the presence of aquifer layers in Bumi Harapan village. This method can determine the value of subsurface resistivity, and from this value, will know the lithology based on the distribution of subsurface resistivity. The lithology results will be described in the form of resistivity logs to make it easier to find the groundwater layer and its depth. Subsurface lithology obtained structures in the form of topsoil, clayey sand, sandy clay and clay. The layers suspected as groundwater layers are sandy clay and clayey sand. The results of the presence of average groundwater at a depth of 4 - 9 meters with sandy clay and clayey sand in the fourth and fifth layers were also found at a depth of 90 - 100 meters below the ground surface. The results of the resistivity values that are thought to be the groundwater layer are found to be 125 – 317 Ωm. Formation factor in determining the type of soil layer as an estimate of groundwater potential Below the surface. The formation factor in this study was found to be in the range of 1.7-8 with a type of aquifer layer to a medium aquifer.
Caldera-Like Delineation and Geological Resources Identification of Majenang Area, Indonesia by Gravity and Magnetic Data Inversions
Authors: Handyarso A.
Published: September 2023

Indonesia’s archipelago formed by the tectonic evolution proceeded with subduction, which was accompanied by volcanism. The systematic subduction zones produce the magmatic arcs with different periods since the Permian up to the Tertiary. However, only the recent Quaternary volcanic arc is recognized and lacked of information about the ancient volcanic environment. Calderas are a crucial feature in any volcanic environment due to the prospect site of geological resources. The Gravity and Magnetic methods are commonly used for preliminary study in almost any cases due to their light-weight, low-cost, and ability to map a wide area rapidly. The inverse-modeling scheme was invoked to estimate the sub-surface situation during the interpretation processes. The study intended to show the ability of both gravity and magnetic method for delineating of caldera-like environment including geological resources prospective site identification. According to the research, a northwest-southeast dextral strike-slip fault found in the area and belongs to the Pamanukan-Cilacap Fault Zone (PCFZ). A circular caldera-like anomaly delineated and interpreted as the ring fault of an ancient volcanic caldera in the study area. Several high gravity anomalies found within the caldera rims are interpreted as lava domes or intrusion rocks, while the high-density found following the outer part of the ring-fault terrain is interpreted as the buried lava. The ancient eruption point inferred around Majenang city, thus the study area proposed as the Majenang Caldera. A mineralization zone identified around the study area, which is comparable with the Cihonje people’s gold mining site as the proven prospective area.
Analyses of explosion earthquakes at Sinabung Volcano: characteristics of waveform, spectra, and energy
Authors: Pritaningtyas Aulia Dhita , Hasib Mohammad , Kriswati Estu , Indrastuti Novianti , Zera Tati
Published: September 2023

The characteristic of explosion earthquakes associated with lava avalanche at Sinabung volcano from October to December 2014 is investigated. The 1-component short-period seismometers which are Sukanalu (SKN), Laukawar (KWR), and Kebayaken (KBY) are used. All stations are located about 3-9 km away from the summit. The result shows the characteristics of these waveforms as follows; the amplitude increases rapidly to maximum for about 2-5 s, then the amplitude is almost constant for about 30-40 s followed by the gradual decrease of amplitude for about 40-50 s. Most of explosion earthquakes have a dominant frequency at about 1-4 Hz. The result also observed that the energy of explosion earthquake changes with lapse time and much stable for longer duration compared with explosion earthquake study at different volcano. Our result suggests that the explosion earthquake at Sinabung volcano may have a different waveform generation and/or mechanism to the general explosion earthquake at different volcano.
A Preliminary Tomography Inversion Study on the Palu Koro Fault, Central Sulawesi Using BMKG Seismic Network
Authors: Jayadi H , Santosa B J , Warnana D D , Zulfakriza Z , Jamroni R , Supendi P , Rosalia S , Muttaqy F , Rachman G , Putra A S , Wijaya A D , Meidji I U
Published: September 2023

The Palu Koro Fault, which frequently causes solid and destructive earthquakes, is the most exciting aspect of Central Sulawesi’s tectonics. We used local earthquake data from the area in this preliminary study. Our preliminary investigation entails analyzing local seismic data and estimating the velocity structure and hypocenter location using a tomographic approach that employs P-wave arrival times from the Agency for Meteorology, Climatology, and Geophysics earthquake observation network from 2010 to 2019. We use a 1-D initial velocity structural model in this tomographic inversion method, and the results are evaluated using the checkerboard test, derivative weight sum, and ray hit count. To the west and east of the Palu Koro Fault area, preliminary tomographic inversion results show a relatively high seismic velocity. These areas are interpreted as West Sulawesi Mandala and East Sulawesi Mandala Poso Fault and Wekuli Fault. The low-velocity anomaly is found near the Palu Koro Fault. Because of the high-speed thrusting, the relocated hypocenters also clustered around the Palu Koro Fault area. In the following activity, we will determine the speed structure of the S wave, which is expected to provide better geological information in the interpretation.
Early Results of Surface Tomography Using Automated Surface-Wave Phase-Velocity Measuring System (ASWMS) in Hawaii
Authors: Nursal K.
Published: September 2023

The Hawaiian Islands are a prominent place to conduct seismicity research. Geologically, occurring earthquakes in this region are unique since it is caused by the presence of a hot spot rather than the common fault activity. The research was conducted using a tomography method called Surface Wave Tomography. The goals of this study are to produce tomographic images of the Hawaiian Islands and to test the accuracy of the Automated Surface-Wave Phase-Velocity Measuring System (ASWMS). ASWMS employs a cross-correlation process to calculate the phase delay between stations, then Eikonal equation to invert the slowness vector to obtain apparent phase velocities, and lastly Helmholtz equation to correct the amplitude to obtain structural phase velocities. The teleseismic data used in this study were collected from stations located throughout the Hawaiian Islands between 2004 and 2009. This study discovered a low-velocity anomaly beneath the Hawaiian Islands with a value of 3.8 – 3.9 km/s, indicating the presence of a low-velocity body. The decrease in velocity with increasing depth suggests an increase in temperature associated with the path that magma takes from the Earth’s mantle to the Earth’s crust beneath the Hawaiian Islands.
Inverse modeling using geomagnetic data of field camp geophysics in Karangsambung (2005-2019)
Authors: Wahyudi Eko J
Published: September 2023

Geomagnetic data from field camp surveys in Karangsambung 2005-2019 were collected and merged. Before 2020 (the restriction of Covid-19 pandemic), there are 4713 and 5984 data of field and base observation in the study area. The purpose of works in this paper are presenting the data collection, simple data processing, and simple calculation of inverse modeling. Fifteen surveys from each year of field camp data acquisition are merged with 2017 survey as reference. The data observation from proton magnetometer are corrected with geomagnetic regional field and diurnal variation (using available data from base observation). Geomagnetic model for 2.5D is calculated using SW-NE slice sections with topographic variation in the study area. The program for inverse model calculation was built to recover distribution of magnetization contrast from surface geomagnetic anomaly. The interpretation of subsurface model should be able to be analyzed and correlated with rock susceptibility and geological surface maps in the study area. From this work, the values of geomagnetic anomaly map are shown in the range of -1600 to 1600 nanoTesla, and the inverse modeling conducted over the Volcanic Breccia in the part of Bukit Brujul area, Basalts and Diabas between Geopark Karangsambung-Parangan-Sadang area, and Clay Breccia in the Sadang-Totogan area.
Hypocenter relocation of the Mw 5.9 eastern Manggarai earthquake 2022 and its aftershocks based on BMKG seismic network
Authors: Ramdhan M , Priyobudi  , Mursitantyo A , Palgunadi K H , Panjaitan A L , Jatnika J
Published: September 2023

The moderate earthquake (Mw 5.9) struck eastern Manggarai and its surroundings on February 21, 2022, at 12:36:00 UTC. Although this earthquake was classified as a moderate earthquake, it produced a significant number of aftershocks. The aftershocks could be observed as the post-seismic activity, which was still well recorded until March 31, 2022. The hypocenter location of the aftershocks is updated by applying the double-difference method. The aftershock distribution is striking in west-east orientation and dipping to the south, emphasizing a geometry of faults. The strike and dip directions are consistent with the focal mechanism determined by the Indonesian Agency for Meteorology, Climatology, and Geophysics (BMKG). Most aftershocks after the relocation are distributed at a depth of < 25 km; the depth of the mainshock is 21.5 km. The aftershock distribution in this study shows that the earthquake sequence propagates toward the up-dip direction. The aftershock relocation also reveals that most aftershocks are situated slightly off the main fault plane in the complex splay faults. Therefore, we conjecture that the co-seismic activity may trigger the aftershocks. In addition, this study also shows that the fault system consists of several fault segments. Our study benefits earthquake disaster mitigation, especially in mapping the segment faults of the Flores backarc thrust.
Sediment thickness in the eastern part of Kalimantan from high-frequency receiver functions
Authors: Syuhada S , Pranata B , Anggono T , Ramdhan M , Febriani F , Prasetio A D , Dewi C N , Hasib M
Published: September 2023

We analyze high-frequency receiver functions from two seismic stations to characterize the sediment properties around the eastern coast of Kalimantan. First, we compute high-frequency receiver functions from teleseismic events using the time-domain deconvolution method. The obtained receiver functions are then stacked using the H-κ stacking approach to determine the sediment properties. The computed receiver functions show the complicated waveforms for the seismic station located near Kutai Basin. These waveforms may indicate the presence of multi sedimentary layers. The H-κ stacking results suggest that the sediment is thinner in the northern part of the area (∼1.34 km depth) than in the southern part of the region (∼3.0 km depth). These results are consistent with the previous geological and geophysical studies conducted in this region. The previous works suggested that the sediment thickness around the study area can reach up to 9 km.