bluuebunny/crossref_metadata_2025 huggingface dataset:
Regional electrical energy substitution potential prediction based on time series and improved back propagation neural network
Authors: Cai Ziwen , Xu Yutao , Xiao Yong , Chen Dunhui , Zhao Yun , Tan Zhukui
Published: November 2023

A combined time-series-based regression forecasting and GRA-IPSO-BP structure is proposed to forecast the electricity replacement forecasts using a time series model based on the triple exponential smoothing forecasting method. The forecast results are corrected using the GRA-IPSO-BP structure. The results of the algorithm show that using a combination of time series and GRA-IPSO-BP structure can significantly improve the forecasting accuracy of electricity replacement compared to single-method forecasting.
Analysis of annual power and electricity balance of hydro-thermal system in Yunnan province based on rolling dispatch with leading reservoir
Authors: Pan Hongyu , Zhao Zhenyu , Zhang Congtong , Chen Kai , Zhou Han , Liu Shuangquan , Yang Qiyu , Jin Tianyu
Published: November 2023

Renewable energy penetration presents challenges for power systems, including unit reconfiguration, resource allocation, and potential electricity shortage. In Yunnan Province, where hydropower is a dominant energy source, annual power and electricity imbalance is a serious issue due to insufficient hydropower regulation capacity and less scheduling flexibility. To address these problems, a rolling dispatch method is proposed to connect medium- and long-term scheduling with short-term scheduling, providing hourly start-stop statuses and output plans for units throughout the year and effectively solving power imbalance issues. Additionally, an economic benefit and electricity shortage analysis of the Longpan leading reservoir in the Jinsha River Basin is conducted, resulting in a 13 billion kWh annual power generation increase and approximately 4 billion yuan in direct economic benefits, greatly improving Yunnan Province’s adjustment ability from dry seasons to wet seasons.
Performance Prediction of a Dual-axis Tracking Solar Trough Collector Based on Artificial Neural Network
Authors: Li Jue , Xia Ting , Wang Ruofan , Chen Haijun , Xu Xiran
Published: November 2023

A dual-axis tracking parabolic trough solar collector, using a certain straight-trough tube, was set up to experimentally investigate the heat collecting performance. An artificial neural network(ANN) model was developed. Experimental data were used to train and predict the mean temperature of Heat transfer fluid in the solar trough collector based on the developed model. The Levenberg-Marquardt (LM) method was also applied to optimize the weights and thresholds for the classic BP Newton algorithm, providing an ANN model with 9 hidden nodes and 30,000 training times. The predicted values are all in good agreement with the experimental data, with a mean relative error of 0.21% and a maximum error of 1.2%. In comparison, the mean relative error of the one-dimensional steady-state model reaches 1.07%. It indicates that the ANN exhibits excellent performance in predicting the export temperature of the solar collector with a specific flow rate of Heat transfer fluid. This ANN model is promising to predict the performance of solar trough collectors under different operating and environmental conditions.
Feasibility study of medium voltage AC fast current limiter
Authors: Yang Zhuo , Du Haifeng , Qin Xiao , Zhao Jinpeng , Dai Huakun , Wu Yifei
Published: November 2023

When a short-circuit fault occurs, it is important to avoid the problem of excessive short-circuit current. This paper offers a current limiter scheme which considers both flow capacity and current limiting capacity. The feasibility of the current limiting scheme is verified by building a simulation model of the power grid around 110/11 kV substation. In addition, the optimal performance parameters of each component of the scheme are determined.
Experimental Study on Condensation Heat Transfer Performance of Hydrophilic/Hydrophobic Microstructured
Authors: He Zhiwei , Wen Enlong , Wang Tao , Huang Chao , Li Shujie , Cai Ruhua
Published: November 2023

In order to study the condensation and heat transfer characteristics of similar microstructure surfaces, two similar microstructure surfaces, cylindrical and circular, were fabricated by femtosecond laser technology on a 0.5 mm silicon wafer. The cylindrical surface is superhydrophobic when the contact angle is more than 150°, and the circular surface is hydrophilic when the contact angle is less than 90°. The difference in condensation heat transfer characteristics between superhydrophobic and hydrophilic microstructures was analyzed, and a visual condensation experimental platform was built. Experimental research showed that: At the same flow rate, the heat transfer coefficient of the superhydrophobic surface and the hydrophilic surface decreases significantly with the increase of the surface subcooling degree, but the heat transfer coefficient of the cylindrical surface is still much larger than that of the circular surface. In addition, the heat transfer performance of the hydrophobic microstructure surface is better than that of the hydrophilic surface at medium and high-speed cooling water flow rates. Although the surface microstructures are similar in shape, the heat transfer performance of cylindrical microstructures is much better than that of circular microstructures under the same conditions, and the heat flux of cylindrical microstructures is 2.2 times that of circular microstructures.
A 10-bit 160 MS/s Asynchronous SAR ADC design
Authors: Wang Jiaqi
Published: November 2023

This study describes a 10-bit 160 MS/s asynchronous successive approximation register (SAR) analog-to-digital converter (ADC) design in a 40 nm CMOS technical process. The SAR ADC is provided with an improved capacitive digital-to-analog converter (CDAC), and the capacitor array is featured by six split high-bit capacitors and a combination of splitting and monotonic switching schemes. This structure and switching scheme can both save power and improve speed while introducing negligible common-mode voltage change. An improved double-tail comparator and TSPC D flip-flops are implemented to further enhance the speed. Simulation results show that the ADC achieves SFDR 72.17 dB, SNDR 61.37 dB, and ENOB 9.90 bits at Nyquist input frequency. The power consumption of the ADC under a 1.2 V power supply is 2.808 mW, achieving 18.4 fJ/conv FoM.
Optimization of Package Heat Dissipation Design Based on High-power WB-BGA Industrial Chip with a Wide Temperature Range
Authors: Duan Shihua , Li Dejian , Guan Yuan , Li Bofu , Li Dameng , Yang Baobin , Han Shunfeng
Published: November 2023

With the progress of science and technology, chip integration and packaging density continue to improve, and the power density increases rapidly, leading to the increasingly prominent problem of chip heat dissipation. The service environment of industrial chips with a wide temperature range is even worse, so it is necessary to ensure reliable operation in the environment of −40°C~85°C. The thermal design and thermal management of packaging have become an important problem in the industry. Based on the wide temperature range of high-power WB-BGA industrial chips, aiming at the difficulty of chip heat dissipation in the high-temperature environment of 85°C, this paper studies and optimizes the packaging heat dissipation, and proposes a high heat dissipation packaging design scheme based on the wide temperature-range high-power WB-BGA industrial chip, which reduces the chip junction temperature by 17.9°C and has a certain reference value for the packaging design of wide temperature range industrial chip.
Research On Etching of Distributed Bragg Reflector
Authors: Gao Yuan , Song Jiejing , Zhou Guo , Fu Xingzhong , Li Xiaolan , Sun Niefeng , Ji Ziwu , Zhang Lijiang
Published: November 2023

This study investigated the effect of etching process parameters on the sidewall morphology and bottom metal etching damage of Distributed Bragg Reflector (DBR), and analyzed the underlying mechanisms. By comparing the etching morphology under different RF power and pressure conditions, it was found that increasing RF power and reducing pressure can solve the problem of sidewall fracture and obtain a smooth sidewall morphology. By comparing the effect of different process gases on the sidewall angle, it was found that adding O2 can reduce the DBR/Photoresit selectivity and sidewall angle while adding BCl3 can increase the DBR/Photoresit selectivity and sidewall angle. Therefore, the sidewall angle can be adjusted by controlling the type and flow rate of the etching gas. By comparing the DBR/metal selectivity under different RF power, it was found that as the RF power decreases, the DBR/metal selectivity increases, which can prevent metal splashing caused by over-etching of metal. Therefore, in DBR etching, high RF power is used for main etching to obtain a smooth sidewall morphology and the sidewall angle can be adjusted by varying the gas type and flow rate, while low RF power is used for over-etching to improve the DBR/metal selectivity and prevent metal over-etching. This study has reference significance for the development of the inverted chip DBR process.
Composite Gate Oxide Method for Improving the Reliability and Leakage Performance of Deep Submicron CMOS Processes
Authors: Zhou Yaohui , Zhang Song , Liu Qun , Wang Dejin , Ma Yaling , Li Mincheng
Published: November 2023

This article aims to address the issues of gate oxide reliability failure and leakage loss in SRAM circuits caused by the introduction of additional high-voltage devices in the 90 nm standard process. It investigates the corner thinning phenomenon using different gate oxide scheme. It analyzes the corresponding relationship between composite gate oxide and reliability and tests the leakage of the SRAM circuit. Research has shown that the use of composite gate oxide can effectively improve corner thinning. The ratio of thermal oxide to HTO in composite gate oxide directly affects GOI/TDDB. At the same time, the use of composite gate oxide also decreases device leakage to a certain extent. The standby leakage of SRAM circuits(Isb) can be reduced from 200 nA to less than 10 nA.
Three-Dimensional Calcium Copper Titanate/Epoxy-Boron Nitride Nanosheets Dielectrics toward High Dielectric Constant and Low Loss
Authors: Yang Yongzhi , Xue Wenqing , Li Yuchao , Zhan Yanhu , Li Yankai
Published: November 2023

Epoxy dielectric materials with high permittivity and low loss were fabricated via inversely introducing epoxy-boron nitride nanosheets (EP-BNNS) mixtures into a continuous three-dimensional CaCu3Ti4O12 (3D CCTO) ceramic network constructed by template method. The obtained 3D CCTO/EP-1.0%BNNS composite exhibited an enhanced permittivity of 25.8 and suppressed low loss of 0.032 (@ 1 kHz), 170%, and 89% of conventional CCTO/EP system, respectively. In addition, the activation energy derived from the isothermal dielectric relaxation spectra increases with the addition of BNNS, indicating that the presence of BNNS restrains the dipolar polarization of EP composites.
Evaluation of p-GaN HEMTs degradation under high temperatures forward and reverse gate bias stress
Authors: Jiang Kun , Deng Jing , Ni Yiqiang , Liu Jun , Liu Xin , He Zhiyuan , He Liang
Published: November 2023

In this study, the degradation behavior and physical mechanism of the p-GaN HEMT devices under high-temperature gate bias (HTGB) with +5 V and −5 V were investigated. The DC characteristics show that the device after forward HTGB stress exhibits an obvious negative threshold voltage (Vth
) shift, while the device after reverse HTGB exhibits a negligible shift. The following explanations could be given for the deterioration mechanism: a portion of the two-dimensional hole gas (2DHG) accumulated in the p-GaN layer at the p-GaN/AlGaN interface under long-term forward bias may fill the trap in the AlGaN layer through the tunneling effect. In addition, the drain-source on-resistance of the device had increased after +5 V HTGB stress, and a distinct decrease of accumulated capacitance was observed in the Cg
-Vg
curve. It indicates a degradation of the gate quality of the device after applying a forward-biased HTGB stress.
Detection of flat-bottom holes in composite materials using multi-dimensional complementary ensemble empirical mode decomposition algorithm
Authors: Zhang Yan , Li Zhaoming , Wang Jin , Zhang Tengda , Zhang Yuzhong
Published: November 2023

Due to high-temperature resistance, high strength, and
excellent fatigue resistance, composite materials are widely used in
automotive manufacturing, aerospace, infrastructure and other
fields. Consequently, the demand for defect detection of composite
materials is also increasing. As a non-destructive testing
technique, the active infrared thermography, which can achieve
full-field defect detection, is suitable for defect detection of
composite materials. However, this method is susceptible to noises
caused by the environment and heating sources. In order to solve the
problem of the defect signal being submerged by these noises, a
multi-dimensional complementary ensemble empirical mode
decomposition (MCEEMD) algorithm is introduced in this paper. This
method can decompose the signal into the low-frequency background
noise, the high-frequency heating noise, and useful defect signals,
and these noises can be easily removed to improve the contrast to
noise ratio (CNR) of defect images. Based on this proposed method, a
defect detection experiment on the carbon fiber reinforced plastic
(CFRP) is performed in this paper, and experimental results show
that the method can effectively remove environmental noise and
heating noise, and it can detect 11 out of 12 defects on the CFRP
sample with an average CNR of 9.107. Compared with the traditional
differential absolute contrast method, this method can detect one
additional small defect with the aspect ratio of 1.67 and one deep
defect with a depth of 2 mm.
Organisms as sensors in biohybrid entities as a novel tool for in-field aquatic monitoring
Authors: Rajewicz Wiktoria , Wu Chao , Romano Donato , Campo Alexandre , Arvin Farshad , Casson Alexander J , Jansen van Vuuren Godfried , Stefanini Cesare , Varughese Joshua Cherian , Lennox Barry , Schönwetter-Fuchs Sarah , Schmickl Thomas , Thenius Ronald
Published: November 2023

Rapidly intensifying global warming and water pollution calls for more efficient and continuous environmental monitoring methods. Biohybrid systems connect mechatronic components to living organisms and this approach can be used to extract data from the organisms. Compared to conventional monitoring methods, they allow for a broader data collection over long periods, minimizing the need for sampling processes and human labour. We aim to develop a methodology for creating various bioinspired entities, here referred to as ‘biohybrids’, designed for long-term aquatic monitoring. Here, we test several aspects of the development of the biohybrid entity: autonomous power source, lifeform integration and partial biodegradability. An autonomous power source was supplied by microbial fuel cells which exploit electron flows from microbial metabolic processes in the sediments. Here, we show that by stacking multiple cells, sufficient power can be supplied. We integrated lifeforms into the developed bioinspired entity which includes organisms such as the zebra mussel Dreissena polymorpha and water flea Daphnia spp. The setups developed allowed for observing their stress behaviours. Through this, we can monitor changes in the environment in a continuous manner. The further development of this approach will allow for extensive, long-term aquatic data collection and create an early-warning monitoring system.
Climate attribution time series track the evolution of human influence on North Pacific sea surface temperature
Authors: Litzow Michael A , Malick Michael J , Kristiansen Trond , Connors Brendan M , Ruggerone Gregory T
Published: November 2023

We apply climate attribution techniques to sea surface temperature time series from five regional North Pacific ecosystems to track the growth in human influence on ocean temperatures over the past seven decades (1950–2022). Using Bayesian estimates of the Fraction of Attributable Risk (FAR) and Risk Ratio (RR) derived from 23 global climate models, we show that human influence on regional ocean temperatures could first be detected in the 1970s and grew until 2014–2020 temperatures showed overwhelming evidence of human contribution. For the entire North Pacific, FAR and RR values show that temperatures have reached levels that were likely impossible in the preindustrial climate, indicating that the question of attribution is already obsolete at the basin scale. Regional results indicate the strongest evidence for human influence in the northernmost ecosystems (Eastern Bering Sea and Gulf of Alaska), though all regions showed FAR values > 0.98 for at least one year. Extreme regional SST values that were expected every 1000–10 000 years in the preindustrial climate are expected every 5–40 years in the current climate. We use the Gulf of Alaska sockeye salmon fishery to show how attribution time series may be used to contextualize the impacts of human-induced ocean warming on ecosystem services. We link negative warming effects on sockeye fishery catches to increasing human influence on regional temperatures (increasing FAR values), and we find that sockeye salmon migrating to sea in years with the strongest evidence for human effects on temperature (FAR ⩾ 0.98) produce catches 1.4 standard deviations below the long-term log mean. Attribution time series may be helpful indicators for better defining the human role in observed climate change impacts, and may thus help researchers, managers, and stakeholders to better understand and plan for the effects of climate change.
Integrated design of a robust superhydrophobic cement mortar layer via sizing sand grains
Authors: Lin Weirong , Wu Tong , Wang Chuanxi , Zheng Ruxin , Wang Dejun , Hu Hui , Cai Anmin , Meng Zhe , Sun Pan , Feng Lei , Shi Yilang , Xiang Shanglin , Cai Dongyu
Published: November 2023

This work reported a facile route for fabricating super-hydrophobic concrete via sizing sand grains. It was found that mixing the sands with a size ranging from 150–180 μm into cement enabled the formation of a lotus-like surface with a papillary structure at micro-scale. SEM showed that the size of bumper was about 3 μm. When spraying a fluorocarbon solution onto this surface, the porous nature of the cement matrix showed the advantage of taking the fluorocarbon into the internal structure of the concrete via capillary force. As a result, the sub surface up to a depth of ∼1.5 mm were transformed into a thick superhydrophobic layer directly. The contact angle (CA) of water droplets could reach 157° on this surface, and which could remain more than 150° after abrasion 100 cycles under a weight of 300 g at 360 grit sandpaper. This thick hydrophobic layer significantly reduced the corrosion rate of the steel the concrete at the Cl- environment by 620 times. The measurement of British pendulum number and compression strength revealed that this superhydrophobic layer was beneficial for maintaining the friction coefficient of the concrete surface in wet condition without altering the mechanical integrity of the concrete.
A dual-route optical emission spectroscopy diagnostic with wide spectral range and high wavelength resolution on HL-2A tokamak
Authors: CHEN 陈 Yue 越 , GAO 高 Jikun 继昆 , LONG 龙 Ting 婷 , NIE 聂 Lin 林 , GAO 高 Jinming 金明 , MA 马 Yao 尧 , HUANG 黄 Yuan 渊 , TIAN 田 Wenjing 文静 , LIU 刘 Yanmin 延民 , ZHU 朱 Xiaodong 晓东 , ZHUANG 庄 Ge 革 , ZHONG 钟 Wulyu 武律 , XU 许 Min 敏
Published: November 2023

A dual-route optical emission spectroscopy (D-OES) diagnostic is newly developed to monitor the optical emission from the X-point plasma region on the HL-2A tokamak. This diagnostic is composed of an imaging system, a beam-splitting system for dual-route measurements, fiber bundles, a spectrometer system, and a control and acquisition system. One route is used to obtain wide-spectral-range spectra, and the other route is used to acquire high-wavelength-resolution line shapes. The spectral resolution of the wide-range spectrometers is 0.8 nm with a coverage of 800 nm (@200–1000 nm). The spectral resolution of the high-resolution spectrometer is 0.01 nm with a coverage of 6 nm (@200–660 nm). The spatial resolution of each route of D-OES is about 4 cm with 11 channels. The temporal resolution is 16 ms at maximum in the single-channel mode. Wide-range spectra (containing Balmer series and a Fulcher band) and highly resolved

line shapes are obtained by D-OES in the hydrogen glow discharge in the lab. D-OES measurements are carried out in the high-density deuterium experiments of HL-2A. The electron density

and deuterium temperature

in the X-point multifaceted asymmetric radiation from the edge (MARFE) region are derived simultaneously by fitting the measured

shape. The density

is observed to increase from ~

to ~

, and the temperature

drops from ~14.4 eV to ~2.3 eV after the onset of MARFE in the discharge #38260.
Multi-layer phenomena in petawatt laser-driven acceleration of heavy ions
Authors: SU 苏 Wanqing 琬晴 , CAO 曹 Xiguang 喜光 , MA 马 Chunwang 春旺 , WANG 王 Yuting 玉廷 , ZHANG 张 Guoqiang 国强
Published: November 2023

Laser-accelerated high-flux-intensity heavy-ion beams are important for new types of accelerators. A particle-in-cell program (Smilei) is employed to simulate the entire process of Station of Extreme Light (SEL) 100 PW laser-accelerated heavy particles using different nanoscale short targets with a thickness of 100 nm Cr, Fe, Ag, Ta, Au, Pb, Th and U, as well as 200 nm thick Al and Ca. An obvious stratification is observed in the simulation. The layering phenomenon is a hybrid acceleration mechanism reflecting target normal sheath acceleration and radiation pressure acceleration, and this phenomenon is understood from the simulated energy spectrum, ionization and spatial electric field distribution. According to the stratification, it is suggested that high-quality heavy-ion beams could be expected for fusion reactions to synthesize superheavy nuclei. Two plasma clusters in the stratification are observed simultaneously, which suggest new techniques for plasma experiments as well as thinner metal targets in the precision machining process.
Numerical analysis for the free-boundary current reversal equilibrium in the AC plasma current operation in a tokamak
Authors: HU 胡 Yemin 业民 , WANG 王 Liuqing 柳青 , BAI 白 Shuhang 书航 , YU 于 Zhi 治 , XIA 夏 Tianyang 天阳
Published: November 2023

In recent decades, tokamak discharges with zero total toroidal current have been reported in tokamak experiments, and this is one of the key problems in alternating current (AC) operations. An efficient free-boundary equilibrium code is developed to investigate such advanced tokamak discharges with current reversal equilibrium configuration. The calculation results show that the reversal current equilibrium can maintain finite pressure and also has considerable effects on the position of the X-point and the magnetic separatrix shape, and hence also on the position of the strike point on the divertor plates, which is extremely useful for magnetic design, MHD stability analysis, and experimental data analysis etc. for the AC plasma current operation on tokamaks.
Spatio-temporal variations of the land-use-related carbon budget in Southeast China: the evidence of Fujian province
Authors: Wu Bowei , Zhang Yuanyuan , Wang Yuan , Wu Shidai , Wu Yong
Published: November 2023

The attainment of a regionally balanced carbon budget is fundamental for the realization of carbon neutrality. This study involved the quantification of the carbon budget related to land use across Southeast China from 2005 to 2020, which was achieved through the calculation of both carbon emissions and carbon sinks. Subsequently, we scrutinized the mechanisms driving the observed dynamic changes in the carbon budget, pinpointed the impact of land-use efficiency (LUE) on the carbon budget, and proposed sustainable spatial planning and management strategies for diverse functional areas at the county level. The core findings are as follows: The dynamics of the carbon budget were spatially heterogeneous, characterized by a gradual increase in carbon emissions over time, while carbon sinks remained relatively constant. The Gini coefficient (G) manifested a gradual increase throughout the study period, reflecting an imbalanced evolution between carbon sinks and emissions. There was also an observable imbalance in the distribution of the carbon ecological carrying coefficient between coastal and inland regions. Land-use-related carbon emissions demonstrated a substantial spatial spillover effect, whereas a weak spatial spillover effect was noted in land-use-related carbon sinks. The correlation between LUE and the carbon budget varied significantly across different functional areas, as the driving effects of LUE displayed remarkable spatial heterogeneity. A quantification of the spatio-temporal alterations and the driving mechanisms behind the carbon budget can aid in the advancement of urban sustainability and regional carbon neutrality.
Mapping the protein–protein interactome in the tumor immune microenvironment
Authors: Peng Rui , Deng Mi
Published: November 2023

The cell-to-cell communication primarily occurs through cell-surface and secreted proteins, which form a sophisticated network that coordinates systemic immune function. Uncovering these protein–protein interactions (PPIs) is indispensable for understanding the molecular mechanism and elucidating immune system aberrances under diseases. Traditional biological studies typically focus on a limited number of PPI pairs due to the relative low throughput of commonly used techniques. Encouragingly, classical methods have advanced, and many new systems tailored for large-scale protein–protein screening have been developed and successfully utilized. These high-throughput PPI investigation techniques have already made considerable achievements in mapping the immune cell interactome, enriching PPI databases and analysis tools, and discovering therapeutic targets for cancer and other diseases, which will definitely bring unprecedented insight into this field.
Lentigo maligna: a review
Authors: Karponis Dimitrios , Stratigos Ioannis A , Joshy Jilse , Craig Paul J , Mistry Khaylen , van Bodegraven Birgitta , Venables Zoe C , Levell Nick J
Published: November 2023

Lentigo maligna (LM) is a melanoma in situ with distinct clinical features and histology. It commonly affects men after the sixth decade of life. Incidence rates of LM have increased based on early 21st century data from different countries; however, data are suboptimal. Data from England show a plateauing crude incidence between 2013 and 2019. By comparison, invasive melanoma and other types of melanoma in situ commonly appears in younger age groups (median age 58 and 67 years old, respectively) and incidence is rising. The most important risk factors for LM include fair skin and cumulative ultraviolet solar radiation exposure. Although LM is limited to the epidermis and connected skin adnexa, it may progress to invasive LM melanoma. The reported rate of malignant progression varies, reflecting a challenge for LM epidemiology research as often lesions are removed on diagnosis. LM poses a challenge in diagnosis and management. Although it can be diagnosed clinically or dermoscopically, histopathological assessment of biopsied skin tissue remains the gold standard. Reflectance confocal microscopy allows for better appreciation of the complexity of LM at a cellular level, often progressing beyond clinical margins. Management of LM may involve Mohs micrographic surgery or excision, although recurrence may occur even with 5 mm clinical margins. Imiquimod cream may be effective, but incomplete treatment and recurrence has been reported. Conservative management with observation or radiotherapy may be used in selected patients’ cases. Five-year net survival rates are excellent. This paper reviews the natural history, epidemiology, aetiology, pathogenesis, diagnosis and management of LM.
Circulating Tumor DNA Clinical Applications in Hepatocellular Carcinoma: Current Trends and Future Perspectives
Authors: Bardol Thomas , Pageaux Georges-Philippe , Assenat Eric , Alix-Panabières Catherine
Published: November 2023

Background

Globally, liver cancers are the second most lethal malignancy after lung cancer (0.83 million deaths in 2020). Hepatocellular carcinoma (HCC) is the predominant type of primary liver cancer and is typically associated with liver fibrosis or cirrhosis. HCC diagnosis relies on histologic examination of surgical specimens or conventional tissue biopsy material. However, standard tissue biopsies are invasive and often do not accurately reflect the tumor heterogeneity. On the other hand, the use of liquid biopsies, represented mainly by circulating tumor DNA (ctDNA) and circulating tumor cells (CTCs), has greatly increased in the past 2 decades. Indeed, liquid biopsies are a noninvasive, repeatable, and sensitive approach to studying tumor biology.

Content

This review describes current clinical applications of ctDNA analysis in the management of patients with chronic liver disease, cirrhosis, and HCC. There is a substantial clinical potential of ctDNA, but interventional studies are still lacking for the moment.

Detection of ctDNA in both asymptomatic individuals and high-risk patients (with chronic liver disease or cirrhosis) contributes to the early diagnosis of HCC. ctDNA analysis also offer tremendous information on the tumor burden and on the risk of early recurrence. The implementation of ctDNA analysis, in association with classical tumor markers (e.g., alpha-fetoprotein), may improve (a) HCC screening in high-risk patients, (b) stratification of the recurrence risk after surgery, and (c) prognosis evaluation of patients with HCC.
Heart transplantation using a donor heart with repaired tetralogy of Fallot: a case report
Authors: Taguchi Takura , Yoshioka Daisuke , Toda Koichi , Miyagawa Shigeru
Published: November 2023

Background

Heart transplantation is the gold standard therapy for end-stage heart failure; however, it is limited by a shortage of available donors. In recent years, heart transplantations have been performed using marginal donor hearts with valvular and/or congenital cardiac abnormalities.

Case summary

A 60-year-old woman with acromegalic cardiomyopathy underwent left ventricular assist device implantation and aortic valve (AV) closure 4 years prior. After 2 months, repeat AV closure and omental flap transposition were performed. During the outpatient follow-up, the patient developed recurrent severe AV regurgitation and bacteraemia-induced subarachnoid haemorrhage. She underwent urgent heart transplantation using a marginal donor heart with preserved cardiac function, mild pulmonary valve stenosis, and regurgitation after pulmonary valve-sparing tetralogy of Fallot (TOF) repair. An anatomical anastomosis was possible. She had no signs of infection, heart failure, arrhythmia, or immune rejection 15 months after the heart transplantation.

Discussion

In this case, the donor heart with repaired TOF did not require pulmonary valve replacement and was anatomically intact. Donor hearts with repaired TOF that are expected to have long-term durability in terms of cardiac function may be used for successful heart transplantations. The repair of marginal donor hearts creates an opportunity to increase the number of viable donors.
Subacute saphenous vein graft stent thrombosis due to unusual drug interaction: a case report
Authors: Koliastasis Leonidas , de Hemptinne Quentin , Severin Simon , Briki Rachid , Xaplanteris Panagiotis
Published: November 2023

Background

Stent thrombosis is a potentially lethal complication of coronary angioplasty and responsible for 20% of all post-angioplasty myocardial infarctions. Unusual causes may be overlooked and difficult to identify.

Case summary

A 70-year-old male with history of triple aortocoronary bypass presented with acute inferolateral ST-segment elevation myocardial infarction (STEMI). Critical stenosis of the vein graft to the right coronary artery was revealed, and with the use of distal embolic protection device, successful angioplasty with stent was performed under double antiplatelet treatment with aspirin and ticagrelor. Two weeks later, he presented again at the emergency department with an acute inferolateral STEMI. Subacute stent thrombosis with complete occlusion of the stented vein graft was evident. Repeated balloon dilatations restored the flow stabilizing the patient; optical coherence tomography showed good stent expansion and apposition. Scrutinizing the patient’s history, we discovered comedication with carbamazepine that is a CYP3A4 inducer and reduces ticagrelor’s effect. Switching to prasugrel ensured potent antiplatelet treatment, and the patient was discharged 5 days later. The 6-month follow-up was uneventful and free of symptoms.

Discussion

Stent thrombosis has dire consequences, and the precipitating factors should always be investigated. Inadequate platelet inhibition secondary to non-compliance to therapy or resistance and suboptimal stent expansion/apposition are its main causes. Drug interactions are an underrecognized factor that may significantly alter the potency of antiplatelet drugs and also lead to stent thrombosis; thus, treatment is essential to be tailored to each patient comedication.
New-onset syncope in diabetic patients treated with sodium-glucose cotransporter-2 inhibitors versus dipeptidyl peptidase-4 inhibitors: a Chinese population-based cohort study
Authors: Gao Xinyi , Zhang Nan , Lu Lei , Gao Tianyu , Chou Oscar Hou In , Wong Wing Tak , Chang Carlin , Wai Abraham Ka Chung , Lip Gregory Y H , Zhang Qingpeng , Tse Gary , Liu Tong , Zhou Jiandong
Published: November 2023

Background and aims

Syncope is a symptom that poses an important diagnostic and therapeutic challenge, and generates significant cost for the healthcare system. Sodium-glucose cotransporter-2 inhibitors (SGLT2i) have demonstrated beneficial cardiovascular effects, but their possible effects on incident syncope have not been fully investigated. This study compared the effects of SGLT2i and dipeptidyl peptidase-4 inhibitors (DPP4i) on new-onset syncope.

Methods and results

This was a retrospective, territory-wide cohort study enrolling type 2 diabetes mellitus (T2DM) patients treated with SGLT2i or DPP4i between 1 January 2015 and 31 December 2020, in Hong Kong, China. The outcomes were hospitalization of new-onset syncope, cardiovascular mortality, and all-cause mortality. Multivariable Cox regression and different approaches using the propensity score were applied to evaluate the association between SGLT2i and DPP4i with incident syncope and mortality. After matching, a total of 37 502 patients with T2DM were included (18 751 SGLT2i users vs. 18 751 DPP4i users). During a median follow-up of 5.56 years, 907 patients were hospitalized for new-onset syncope (2.41%), and 2346 patients died from any cause (6.26%), among which 471 deaths (1.26%) were associated with cardiovascular causes. Compared with DPP4i users, SGLT2i therapy was associated with a 51% lower risk of new-onset syncope [HR 0.49; 95% confidence interval (CI) 0.41–0.57; P < 0.001], 65% lower risk of cardiovascular mortality (HR 0.35; 95% CI 0.26–0.46; P < 0.001), and a 70% lower risk of all-cause mortality (HR 0.30; 95% CI 0.26–0.34; P < 0.001) in the fully adjusted model. Similar associations with syncope were observed for dapagliflozin (HR 0.70; 95% CI 0.58–0.85; P < 0.001), canagliflozin (HR 0.48; 95% CI 0.36–0.63; P < 0.001), and ertugliflozin (HR 0.45; 95% CI 0.30–0.68; P < 0.001), but were attenuated for empagliflozin (HR 0.79; 95% CI 0.59–1.05; P = 0.100) after adjusting for potential confounders. The subgroup analyses suggested that, compared with DPP4i, SGLT2i was associated with a significantly decreased risk of incident syncope among T2DM patients, regardless of gender, age, glucose control status, Charlson comorbidity index, and the association remained constant amongst those with common cardiovascular drugs and most antidiabetic drugs at baseline.

Conclusion

Compared with DPP4i, SGLT2i was associated with a significantly lower risk of new-onset syncope in patients with T2DM, regardless of gender, age, degree of glycaemic control, and comorbidity burden.
Inflammation-based scores in benign adrenocortical tumours are linked to the degree of cortisol excess: a retrospective single-centre study
Authors: Favero Vittoria , Prete Alessandro , Mangone Alessandra , Elhassan Yasir S , Pucino Valentina , Asia Miriam , Hardy Rowan , Chiodini Iacopo , Ronchi Cristina L
Published: November 2023

Objective

Benign adrenocortical tumours are diagnosed in ∼5% of adults and are associated with cortisol excess in 30%-50% of cases. Adrenal Cushing's syndrome (CS) is rare and leads to multiple haematological alterations. However, little is known about the effects of the much more frequent mild autonomous cortisol secretion (MACS) on immune function. The aim of this study was to evaluate the haematological alterations in benign adrenocortical tumours with different degrees of cortisol excess.

Design and methods

We investigated 375 patients: 215 with non-functioning adrenal tumours (NFAT), 138 with MACS, and 22 with CS. We evaluated the relationship between the degree of cortisol excess and full blood count as well as multiple inflammation-based scores, including the neutrophil-to-lymphocyte ratio (NLR), the lymphocyte-to-monocyte ratio (LMR), and the systemic immune-inflammation index (SII).

Results

We observed a gradual and significant increase of leucocytes, neutrophils, and monocytes across the spectrum of cortisol excess, from NFAT over MACS to CS. Neutrophil-to-lymphocyte ratio and SII were significantly higher in both MACS and CS when compared to NFAT (P < .001 and P = .002 for NLR and P = .006 and P = .021 for SII, respectively). Conversely, LMR was lower in MACS and CS than in NFAT (P = .01 and <.001, respectively) but also significantly lower in CS compared to MACS (P = .007).

Conclusions

Neutrophil-to-lymphocyte ratio, SII, and LMR correlated with the degree of cortisol excess in benign adrenocortical tumours and were altered in patients with CS and MACS. These findings suggest that, similar to clinically overt CS, MACS also affects the immune function, potentially contributing to the MACS-associated comorbidities.
Left atrial total emptying fraction measured by cardiovascular magnetic resonance imaging predicts low-voltage areas detected during electroanatomical mapping
Authors: Löbe Susanne , Stellmach Pierre , Darma Angeliki , Hilbert Sebastian , Paetsch Ingo , Jahnke Cosima , Bollmann Andreas , Hindricks Gerhard , Kircher Simon
Published: November 2023

Aims

Low-voltage areas (LVAs) found during left atrial (LA) electroanatomical mapping are increasingly targeted by radiofrequency catheter ablation (RFCA) on top of pulmonary vein isolation to improve arrhythmia-free survival in patients with atrial fibrillation (AF). However, pre-procedural prediction of LVAs remains challenging. The purpose of the present study was to describe the association between parameters of LA function and dimensions, respectively, derived from pre-procedural cardiovascular magnetic resonance (CMR) imaging, and the presence of LVAs on LA voltage mapping.

Methods and results

Patients who underwent first-time RFCA for paroxysmal or persistent AF and who were in stable sinus rhythm during pre-procedural CMR imaging were included in this study. Cardiovascular magnetic resonance–derived parameters of LA function and dimensions were calculated. Low-voltage areas were defined as areas with bipolar voltage amplitudes of ≤0.5 mV on electroanatomical mapping. In total, 259 consecutive patients were included in this analysis. Low-voltage areas were found in 25 of 259 patients (9.7%). Compared with those without LVAs, patients with LVAs were significantly older, were more likely to be female, had a higher CHA2DS2-VASc score, had larger LA volumes, and had a lower LA total emptying fraction (TEF). In multivariate analysis, only LA TEF [odds ratio (OR) 0.885, 95% confidence interval (CI) 0.846–0.926, P < 0.001] and the CHA2DS2-VASc score (OR 1.507, 95% CI 1.115–2.038, P = 0.008) remained independently associated with the presence of LVAs.

Conclusion

Left atrial TEF and the CHA2DS2-VASc score were independently associated with the presence of LVAs found during LA electroanatomical mapping. These findings may help to improve pre-procedural prediction of pro-arrhythmogenic LVAs and to improve peri-procedural patient management.
A roadmap to advance exposomics through federation of data
Authors: Schmitt Charles P , Stingone Jeanette A , Rajasekar Arcot , Cui Yuxia , Du Xiuxia , Duncan Chris , Heacock Michelle , Hu Hui , Gonzalez Juan R , Juarez Paul D , Smirnov Alex I
Published: November 2023

The scale of the human exposome, which covers all environmental exposures encountered from conception to death, presents major challenges in managing, sharing, and integrating a myriad of relevant data types and available data sets for the benefit of exposomics research and public health. By addressing these challenges, the exposomics research community will be able to greatly expand on its ability to aggregate study data for new discoveries, construct and update novel exposomics data sets for building artificial intelligence and machine learning-based models, rapidly survey emerging issues, and advance the application of data-driven science. The diversity of the field, which spans multiple subfields of science disciplines and different environmental contexts, necessitates adopting data federation approaches to bridge between numerous geographically and administratively separated data resources that have varying usage, privacy, access, analysis, and discoverability capabilities and constraints. This paper presents use cases, challenges, opportunities, and recommendations for the exposomics community to establish and mature a federated exposomics data ecosystem.
International Microorganism Day: facilitating global outreach events using a decentralized model
Authors: Koursari Eleni , Shuttleworth Joseph Brooks
Published: November 2023

On 17 September 1683, Antonie van Leeuwenhoek, a Dutch merchant who lacked formal education and fortune, wrote a letter to the Royal Society of London describing for the first time a single-celled organism. As a tribute to this revolutionary discovery, the Portuguese Society of Microbiology with the support of the Federation of European Microbiological Societies in 2017, designated this day as International Microorganism Day (IMD), a day aiming to raise awareness about the wonderful world of microbes. Six years after the establishment of IMD, the knowledge of microbiology outreach around this celebration has expanded greatly, with 5 years of in-person and 2 years of online events. The peak of these commemorations was in 2023, with 63 parallel outreach events and more than 5000 attendees, most of which were children, and young adults. While these in-person events were occurring in the month of September, the #InternationalMicroorganismDay hashtag reached nearly 2.3 million people online, reflecting the number of users who have seen a post containing this hashtag on social media. Using a decentralized model to facilitate 63 grass-roots teams to organize events locally, IMD achieved global representation both online and offline. This paper presents details behind the organization and data on the international impact of the IMD 2022 and 2023 events, outlines plans to expand reach to more countries and audiences, and encourages readers to participate with their own events in future IMD editions so that global impact can be expanded even further.
Therapeutic effects of fenticonazole on bacterial vaginosis in mice
Authors: Yu Jinfen , Peng Peiran , Zhu Jun , Yao Chao , Dai Hongbo , Mei Ru
Published: November 2023

Bacterial vaginitis (BV) is a syndrome of increased vaginal discharge, fishy smelling leucorrhea, and itching and burning vulva caused by the microecological imbalance in the vagina induced by mixture of Gardnerella vaginalis (GV) and some anaerobic bacteria. Fenticonazole, an imidazole derivative and antimicrobial compound, has been demonstrated to exert effective therapeutic effects in mixed vaginitis. Accordingly, our study was designed to explore the potential role of fenticonazole in GV-infected BV mouse models. Female C57/BL6 mice were injected intraperitoneally with β-estradiol 3 days before and on the day of GV infection to maintain a pseudoestrus state. On the day of infection, mice were intravaginally inoculated with 20 µl of a suspension of GV (6 × 106 CFU/ml). Fenticonazole was administered as 2% vaginal cream (0.2 mg each mouse) by intravaginal application once a day for 3 days beginning the day of infection. At day 3 postinfection, the mice were sacrificed and vaginal washes were harvested. GV proliferation and Lactobacillus content were calculated in the vaginal lavage. Neutrophil counts in the vaginal lavage were observed through Pap staining. Myeloperoxidase (MPO) activity and proinflammatory cytokine (TNF-α, IL-1β, IL-6, iNOS, COX2, and NF-κB) levels in vaginal tissues were measured by ELISA and western blotting. Vaginal tissues were stained by hematoxylin and eosin (H&E) to examine the exfoliation of vaginal epithelial cells. GV infection increased GV proliferation and neutrophil counts but reduced Lactobacillus content in the vaginal lavage, as well as enhanced MPO activity, proinflammatory cytokine levels, and the exfoliation of vaginal epithelial cells in vaginal tissues of BV mouse models. However, administration of fenticonazole significantly ameliorated the above phenomena. Fenticonazole greatly improves the symptoms of GV-induced BV in mouse models.
Direct contact of fermented rice bran beds promotes food-to-hand transmission of lactic acid bacteria
Authors: Niwa Ryo , Chen Dominique , Seong Young ah , Jo Kazuhiro , Ito Kohei
Published: November 2023

The skin microbiome, which varies widely between individuals, plays a crucial role in human health. It also interacts with the environment in various ways, including during the preparation of fermented food. Nukadoko is a pickle and traditional fermented food in Japan that utilizes lactic acid bacteria to ferment vegetables. When preparing or maintaining Nukadoko, it is mixed with bare hands. Despite the known interaction between Nukadoko and human skin, no studies have explored its impact on Nukadoko quality or skin microbiome changes. This study examines these effects during Nukadoko maintenance. Three participants were asked to stir commercially available late-stage Nukadoko for 14 days and not stir it for the remaining 14 days to examine microbial settlement and shedding. Microbiome analysis was performed on human skin and Nukadoko. We found that microorganisms from rice bran beds can temporarily settle on human skin but are shed quickly. Stirring rice bran beds by hand may have short-term effects on the skin microbiome. This study provides insights into the communication between human and food microbiomes in traditional Japanese fermented foods.