bluuebunny/crossref_metadata_2025 huggingface dataset:
Numerical investigation of the flow noise of an underwater vehicle
Authors: Wu Jiafeng , Cao Xiaoming , Liu Bing , Wu Gang , Wei Wei
Published: May 2024

Flow noise is an important issue of underwater vehicles. In this paper, the ability of different numerical methods to predict the flow noise of the DARPA SUBOFF underwater vehicle model is investigated and compared. It is found that the front of the command deck and the tail fins are the main noise sources. Numerical results show that delayed detached eddy simulation is a suitable computational model for flow noise simulations.
Study on the steady state position of ocean towing cables
Authors: Wang Jian , Wu Hengfei , Liang Rongzhen
Published: May 2024

A study is conducted on the static equilibrium posture of the towing cable in water under a constant speed state in the towing system. Firstly, the underwater force state of the towing body is calculated and then the posture and tension of the towing cable are analyzed and calculated. As the cable is divided into two states which are above water and below water, a differential equation system is established as the boundary. The initial value of the equation can be transformed by the drag and gravity values of the towing body. The program solves the differential equations using the fourth-order Runge Kutta method and draws the attitude curve. Finally, it verifies the theoretical calculation results through experiments.
Fluid-structure interaction dynamic analysis of large civil aircraft tank sloshing
Authors: Xu Chengliang , Xu Feng
Published: May 2024

To meet the requirements of passengers, the tank volume of large civil aircraft is gradually increasing, which brings certain risks. Under different 0 pertaining conditions during the flight, the liquid in the tank will cause structural failure and affect the aircraft’s safety. Therefore, based on the assumption of an ideal fluid, the smooth particle method (SPH) combined with the finite element method (FEM) is used to establish the coupling dynamic equation between the tank and the liquid. The effects of sloshing impact on the water tank under different filling rates were studied, and the influences of the water wave shape, the center of gravity shift, stress distribution, and deformation of the tank were obtained. The results show that the mass accumulation of water particles occurs in the acceleration stage, the relative center of gravity changes greatly in less water, and the accumulated liquid greatly influences the tank under the action of inertia. The more liquid in the tank is, the more the impact effect on the tank increases. The analysis results provide some reference for the analysis and design of tank anti-sway plates and flight attitude adjustment.
Joint stress of a hinged platform composed of eight boxes
Authors: Zhao Jiancheng , Zhang Bihui , An Hao , Sun Rui
Published: May 2024

The box-type hinged platform has important applications in ocean engineering. In this paper, a multi-module assembled box-type platform is described. The mid-section load of the platform is numerically simulated based on the three-dimensional velocity potential theory and the indirect time-domain method through the hydrodynamic module AQWA in ANSYS. The stress of the hinged joints of platforms was performed using finite element analysis software in ANSYS software. The results show that: (1) In irregular waves, the shear force and bending moment in the middle section of the platform increases with the increase of the significant wave height; (2) Under the same towing scheme, the stress of the hinged joints between box platforms shows an increasing trend with the increase of wave level. Under the same wave working condition, the stress at the uniaxial nut of the hinged joints is relatively high, which is prone to fracture.
Computations on fall of the leaning tower with considering air resistance
Authors: Xie Cuili
Published: May 2024

The free fall of a sphere was studied by considering air buoyancy and resistance. After selecting the reasonable drag coefficient formula recommended by the literature, partial differential formulas on the motion of balls falling in the Leaning Tower of Pisa are solved. The variation process of acceleration, velocity and displacement over time during the falling process of two spheres is obtained. The research results indicate that the kinematics of free fall considering air resistance is different from that neglecting air resistance. Air Resistance must be considered in the free fall of the solid ball after 0.3005 seconds. In the free fall of the leaning tower, air resistance makes the solid ball land at 0.4418 seconds which is earlier than the hollow. The variation of the acceleration of a solid ball with time can be described by a second-order function a=-0.115t2
-0.022t+9.801. Velocity does not satisfy the product of acceleration and time but can be described as a polynomial function of the velocity variation with time v = c1t2
+ c2t + c3
. About the relationship between displacement and time, for a solid sphere, displacement is proportional to 1.9526 power of time h=5.4945t1.9526
, while for a hollow sphere, it cannot be expressed by a function. The relationship between air resistance and velocity during the falling process of an iron ball satisfies a polynomial function Fd
=c1v2
-c2v+c3
rather than a simple relationship where air resistance is directly proportional to the first or second power of speed, which was used in many papers as a reasonable assumption.
Performance investigation of doped multi-layer graphene nanoribbon as interconnects in modern technology nodes
Authors: Wu Qixiao , Pan Zhongliang
Published: May 2024

In this paper, the performance of intercalation doped multilayer graphene nanoribbons (MLGNR) with modern technology nodes is meticulously investigated. An unconditionally stable FDTD method is used to analyze the transient output of the circuit. Several cases of MLGNR interconnects under different doping materials, stacking directions and contact modes have been discussed. With multiple experiments carried out, it is shown that the Li-doped MLGNR interconnect with vertical stacking orientation has the most outstanding performance, which has the least delay compared with the traditional Cu interconnect and other counterparts in 3-nm and 5-nm nodes. In summary, the Li-doped vertically stacked MLGNR is very promising for carbon nano interconnects in the next generation of integrated circuits.
The Impact and analysis of nuclear power plant’s steam extraction and heating modification on the turbine
Authors: Li Shuaishuai , Qu Tianzuo , Wang Dalin
Published: May 2024

A certain nuclear power unit uses the circulating water heated by the steam extraction from the high-pressure cylinder exhaust pipe of the steam turbine through modification, and the pressurized heating circulating water is supplied to the outside of the plant. As it is the first large-scale model of steam extraction heating in domestic nuclear power, the heating will have a certain impact on the steam turbine. Therefore, it is necessary to analyze the impact of large-scale steam extraction on the steam turbine and propose corresponding countermeasures to provide relevant references for subsequent nuclear power extraction and heating modification.
Heat exchange characteristics between u-shaped butted well and reservoir
Authors: Qu Yanlin , Li Fengming , Wang Zhaoliang
Published: May 2024

The geothermal resources in Shandong are relatively abundant. However, due to geological conditions, the high pressure of formation water reinjection makes it difficult and costly to achieve a 1:1 ratio of formation water extraction/reinjection during geothermal resource extraction. This causes waste of formation water resources and does not meet environmental protection requirements. The U-shaped butted well heat exchanger at the bottom of the well can achieve “heat extraction without water extraction”, effectively solving the problems of difficult formation water reinjection, pipeline reservoir corrosion, and reservoir damage in Shandong. Therefore, to explore the heat exchange characteristics between the U-shaped butted well heat exchanger at the bottom of the well and the reservoir, it is necessary to study various parameters of the heat exchanger operation. To better reflect the heat transfer status between the butted well and the soil, FLUENT software was used for simulation. Through simulation, the operation diagram of the generator after the comprehensive renovation was analyzed, guiding the operation of the U-shaped butted well heat exchanger.
Synthesis of biomass nitrogen-doped catalysts and their electrocatalytic performance in fuel cells
Authors: Ren Guohong , Sun Wei , Chen Yuting , Liu Chunyu , Song Kangle , Liu Xiaohong , Liu Zhongsu
Published: May 2024

At present, biomass materials have the characteristics of low cost, stability, and relatively high activity, which is expected to replace platinum-based (Pt) materials as cathode catalysts. In this paper, Zn, Fe-N-C catalyst materials and Fe-N-C catalyst were composited by high-temperature calcination. Their crystal and morphological structures were featured by X-ray diffraction instruments (XRD) and scanning electron microscopy (SEM). Their activity and stability to oxygen reduction were tested by an electrochemical workstation, and it was found that Zn, Fe-N-C catalyst materials had the best performance. The investigation of this paper can furnish an effective method for oxygen reduction reaction catalysts.
Analysis of the correlation between GIS partial discharge current waveform and charge quantity with UHF signals
Authors: Qian Hanming , Zeng Xiangjun , Zhou Ke , Zhang Wei
Published: May 2024

The Ultra-High Frequency (UHF) method, as a crucial technology for online GIS monitoring, struggles with the issue of being unable to accurately reflect the number of partial discharges, which poses a significant challenge for this technique. To examine the relationship between partial discharge waveforms, charge quantity, and UHF signals, a physical field model of partial discharge is developed using finite element simulation software, allowing a comparison of the peak-to-peak values of UHF signals with the parameters of the partial discharge current. Research demonstrates a roughly linear relationship between the peak-to-peak values of UHF signals and the magnitude of the partial discharge current but no definitive connection with the discharge quantity. These significant findings guide the quantitative detection of partial discharges in electrical equipment using the UHF method.
Active power control of wind turbine based on fuzzy pitch control
Authors: Liu Chengzhi , Li Qiang , Wang Chenggen , Xv Tianyi , Gu Wei , Yin Minghui
Published: May 2024

With the continuous increase in wind power penetration rate, wind turbine generators (referred to as WTGs or wind turbines) need to have the capability of active power control (APC) to respond to grid power commands. To reduce the burden of pitch control on wind turbines, existing studies have adopted a technological approach that uses variable-speed operation of the wind rotor instead of pitch control. Typically, pitch control is only initiated at the speed boundaries to limit variable-speed operation within the speed range. However, due to the influence of factors such as wind speed, rotor speed and control parameters, there is a noticeable saturation phenomenon in pitch control at the speed boundaries, which can affect the variable-speed process of the wind rotor and APC performance within the speed range. Therefore, this paper determines whether blade pitch adjustment needs to be performed in advance when the wind turbine operates within the speed range based on the rotor speed state. This avoids the pitch action at the speed boundaries and the associated pitch saturation problem. The results show that the proposed method in this paper reduces the frequency of the rotor speed reaching the speed boundaries by performing pitch actions within the speed range. This alleviates the influence of pitch saturation on the variable-speed process of the wind rotor, as well as the occurrence of overspeed and electromagnetic power drop, thereby improving the APC performance of the wind turbine.
Design and testing of a high-performance solar LED streetlight
Authors: Peng Manman , Li Chaoqun , Li Junmin
Published: May 2024

This paper presents the development and validation of a high-performance solarpowered charging streetlight. Our controller incorporates various charging modes, including MPPT charging, constant current charging, and constant voltage charging, and the controller can automatically change the charging mode based on the battery level. The streetlight can achieve brightness adjustment through PWM adjustment. The controller turns off the streetlights once the battery voltage reaches the over-discharge protection voltage. However, turning off the streetlights inevitably results in a voltage rebound above the over-discharge protection voltage. Consequently, the streetlights enter a cycling pattern of illumination and extinguishment. We have addressed this issue by incorporating a voltage rise threshold in the controller program, effectively preventing the streetlights from cycling between illumination and extinguishment. The MCU (Micro Controller Unit) can output multiple sets of PWM waves, where each set can control the on/off state of an LED light group. Combining multiple LED groups enables the driving and control of high-power LED street lights. We designed and constructed two solar-powered LED lighting systems to demonstrate the practicality of our approach. Extensive long-term outdoor field tests validate the robust performance of our control system.
Transformer parameter estimation in distribution network based on deformable transformer
Authors: Sun Zhiqing , Xuan Yi , ZikaiCao  , Liu Jian , Dai Tiechao , Liu Weihao , Ye Gangjin , Liang Yundan , Huang Jianping , Huang Yi , Fan Libo , Liu Xingye , Zhang Jiansong , Jin Minhao , Huang Jiabin
Published: May 2024

With the large number of distributed power sources and the dynamic change of load, the abnormal parameters of distribution transformers become more and more complicated. So it is particularly important to estimate their parameters accurately. For a low voltage distribution network with a limited number of measuring equipment, a Transformer parameter estimation method based on a Deformable Transformer is proposed in this paper. Firstly, a Transformer parameter estimation model based on a Deformable Transformer network is established by using historical measurement data. Then, a quality evaluation method of parameter estimation is proposed to test the accuracy of parameter estimation. Finally, the effectiveness of the proposed method is verified by practical data.
Evaluation of heat transfer correlations for two-phase flow boiling in twisted tapes inserted tubes
Authors: He Yan , Tang Chao , Chen Dongsheng
Published: May 2024

Many experimental researches were conducted in the twisted tapes inserted tubes, and many correlations were proposed and evaluated. However, most of the evaluations were based on specific experimental data, and the number of correlations evaluated was limited in each paper. This paper conducted a review of correlations and experimental investigations of the two-phase flow boiling heat transfer coefficient for twisted tapes inserted tubes, the key forms of the 5 correlations were reviewed, and the prediction accuracy of the 5 correlations was evaluated against the 508 published experimental data. This paper proposed a new correlation which has a MAD of 17.2%, 10.2% lower than the best existing correlation.
Periodic sampling and count rate correction of the low energy X-ray telescope on board the Insight- Hard X-ray modulation telescope
Authors: Li W. , Lu J.B. , Zhao X.F. , Cui W.W. , Yang Y.J. , Chen Y.
Published: May 2024

The Low Energy X-ray Telescope (LE) is an important
instrument of the Insight-Hard X-ray Modulation Telescope
(Insight-HXMT), which performs scanning and point observation in the
soft X-ray energy band (0.7–13 keV). Since its launch in 2017,
it has conducted a large number of scientific observations and
achieved significant astronomical discoveries. LE is composed of
three detector boxes and an electronic control box. The data
acquisition system of LE is designed to use periodic sampling, which
solves the problem of unstable noise peaks. Data loss may occur when
observing X-ray bursts, and periodic sampling provides a method of
correcting light curves. In addition, in the South Atlantic Anomaly
(SAA) or where the count rate of the particle monitor on the
Insight-HXMT is very high, LE automatically switches into SAA
operating mode, and only a small number of events are
recorded. After data correction, the light curves can be estimated
to expand the astronomical achievements of LE.
Precipitation exacerbates spatial heterogeneity in the propagation time of meteorological drought to soil drought with increasing soil depth
Authors: Hu Chen , Xia Jun , She Dunxian , Wang Gangsheng , Zhang Liping , Jing Zhaoxia , Hong Si , Song Zhihong
Published: May 2024

The propagation of meteorological droughts to soil droughts poses a substantial threat to water resources, agricultural production, and social systems. Understanding drought propagation process is crucial for early warning and mitigation, but mechanisms of the propagation from meteorological drought to soil drought, particularly at varying soil depths, remain insufficiently understood. Here, we employ the maximum correlation coefficient method and the random forest (RF) model to investigate the spatiotemporal patterns and drivers of propagation time (PT) from meteorological drought to soil drought at four different depths across China from 1980 to 2018. Our findings reveal consistently higher PT in northern China and lower PT in southern China across varying soil depths, with more pronounced spatial heterogeneity with increasing soil depth. Furthermore, we identify temperature and precipitation as determinants of spatial patterns of PT in surface and deeper soil layers, respectively. Additionally, precipitation emerges as the dominant factor influencing changes in PT between different soil layers. Our study highlights a discernible shift in PT drivers from temperature to precipitation as soil depth increases and the significant impact of precipitation on exacerbating spatial heterogeneity in PT. This study contributes to an enhanced comprehension of the propagation process from meteorological drought to soil drought at different depths, which can aid in establishing practical drought mitigation measures and early warning systems.
Tunable polarization-independent and angle-insensitive ultra-broadband terahertz absorber with vanadium dioxide
Authors: Dong Liang , Xiang Huanqi , Zhu Lei , Wang Yun , Rong Miaoxin
Published: May 2024

In this paper, a tunable ultra-broadband terahertz metamaterial absorber is proposed based on the phase transition material of vanadium dioxide (VO2). The absorber cell consists of a petal-like monolayer vanadium dioxide, a dielectric layer, and a metal layer. The terahertz absorption bandwidth of more than 90% absorptance reaches 4.2 THz, which covers from 1.99 to 6.19 THz, and a relative bandwidth attains to 102.7%. By changing the conductivity of VO2, the absorbance of this structure can be dynamically adjusted from 2.4% to 98.96%. The physical mechanism of the perfect absorption in this paper is investigated by the impedance matching theory and electric field distributions. The results show that the strong coupling effect in the petal-like structure contributes to the broadening of the absorption spectrum, and the absorber is polarization-insensitive and wide-angle incidence-insensitive due to the symmetry of the cell structure. The metamaterial absorber designed in this paper is expected to have a wide range of applications in the fields of terahertz imaging, stealth, sensing and detection.
The Unique Job
Authors: Williams Abiodun
Published: May 2024

The first chapter outlines the formal responsibilities of the unique job of UN Secretary-General, and the Secretary-General’s different roles, including as a mediator of conflict, an administrator, and an initiator of ideas, policies, and norms. It provides an overview of the dynamic relationship between the Secretary-General and the Security Council, which is important for the UN’s activities, especially in managing international peace and security. It includes an account of the process that led to Kofi Annan’s appointment as Secretary-General after the United States (US) decided for largely domestic reasons to veto a second term for his predecessor, Boutros Boutros-Ghali. It examines Annan’s bold vision for the Secretary-Generalship which emphasized that the UN, founded in the name of “We the peoples,” must advance their interests in development, security, and human rights. It explains how Annan used the “bully pulpit” to articulate a global agenda, to resist the pressure of powerful member states, and to influence global public opinion.
Conflict Prevention
Authors: Williams Abiodun
Published: May 2024

Chapter 2 considers Kofi Annan’s initiatives relating to the primary purpose of the UN, which is to prevent war and to strengthen means for conflict resolution. He regarded preventing deadly conflicts as vital for the preservation of human life and for promoting sustainable development and human rights. It examines his ideas on moving the UN “from a culture of reaction to a culture of prevention” and how he tried to apply them in the organization’s work. It includes a case study of his successful mediation between Nigeria and Cameroon over the disputed Bakassi Peninsula that prevented a war between the two countries. The chapter also discusses his role in providing clear remedies to the deficiencies of UN peacekeeping, and in establishing the UN’s Peacebuilding Architecture consisting of the Peacebuilding Commission, the Peacebuilding Fund, and the Peacebuilding Support Office to support sustainable peace.
Pollinator shift ensures reproductive success in a camouflaged alpine plant
Authors: Huang Tao , Song Bo , Chen Zhe , Sun Hang , Niu Yang
Published: May 2024

Background and Aims

There are intrinsic conflicts between signalling to mutualists and concealing (camouflaging) from antagonists. Like animals, plants also use camouflage as a defence against herbivores. However, this can potentially reduce their attractiveness to pollinators.

Methods

Using Fritillaria delavayi, an alpine camouflaged plant with inter-population floral colour divergence, we tested the influence of floral trait differences on reproduction. We conducted pollination experiments, measured floral morphological characteristics, estimated floral colours perceived by pollinators, analysed floral scent and investigated reproductive success in five populations.

Key Results

We found that the reproduction of F. delavayi depends on pollinators. Under natural conditions, a flower-camouflaged population had 100 % fruit set and similar seed set to three out of four yellow-flowered populations. Bumblebees are important pollinators in the visually conspicuous yellow-flowered populations, whereas flies are the only pollinator in the flower-camouflaged population, visiting flowers more frequently than bumblebees. The camouflaged flowers cannot be discriminated from the rock background as perceived by pollinators, but may be located by flies through olfactory cues.

Conclusions

Collectively, our results demonstrate that the flower-camouflaged population has different reproductive traits from the visually conspicuous yellow-flowered populations. A pollinator shift from bumblebees to flies, combined with high visitation frequency, compensates for the attractiveness disadvantage in camouflaged plants.
Development of a 12-Word Version of a Verbal Learning Test for Persian-Speaking Older Adults: Reliability, Construct Validity, and Normative Standards
Authors: Rahmani Fahimeh , Khanjani Mohammad Saeed , Azkhosh Manoochehr , Younesi Seyyed Jalal , Hassani-Abharian Peyman , Hoseinzadeh Samaneh , Sayadnasiri Mohammad
Published: May 2024

Objective

As people enter old age, they develop diseases, challenges, and cognitive and behavioral deficits that are associated with decreased abilities. Memory abilities and deficiencies and impaired models can be assessed using neuropsychological instruments, and a rehabilitation program can be developed based on the individuals’ memory deficits. The present cross-sectional research aims to develop a new test (henceforth known as the Persian Verbal Learning Test, or PVLT) that is appropriate for Persian-speaking older adults.

Methods

For normative data, we administered PVLT to a group of 374 Persian-speaking healthy older adults consisting of both genders (190 women and 184 men) who were aged 60–89 years old. To determine reliability and validity, we evaluated neurologically healthy older adults and analyzed the results using intraclass correlation coefficient (ICC) and Pearson’s correlation coefficient.

Results

The present findings showed that age, education, and gender significantly affect subtests of the PVLT. In the evaluation of reliability, significant positive correlations were observed between the variables of the PVLT in the standard/standard form. Furthermore, moderate correlations were observed between PVLT variables (immediate recall, short-delay recall, long-delay recall, and recognition), and the Immediate and Delayed Logical Memory subtests of Wechsler Memory Scale-Revised (WMS-R). However, subtests of the PVLT also showed significantly positive correlations with MoCA and non-verbal variables of WMS-R.

Conclusion

According to the results of this study and given the good psychometric properties obtained, PVLT can potentially be used as a more appropriate tool than the SVLT for Persian-speaking older adults.
Transposable elements alter gene expression and may impact response to cisplatin therapy in ovarian cancer
Authors: Mombach Daniela Moreira , Mercuri Rafael Luiz Vieira , da Fontoura Gomes Tiago Minuzzi Freire , Galante Pedro A F , Loreto Elgion Lucio Silva
Published: May 2024

Cisplatin is widely employed for cancer treatment; therefore, understanding resistance to this drug is critical for therapeutic practice. While studies have delved into differential gene expression in the context of cisplatin resistance, findings remain somewhat scant. We performed a comprehensive investigation of transposable elements (TEs) expression and their impact in host genes in two cisplatin-treated ovarian cancer cell lines. RNA-seq, ATAC-seq, and in-depth bioinformatics analysis were used to compare cisplatin-sensitive and -resistant ovarian cancer cell lines. Our results reveal that cisplatin therapy alters not only the expression of protein-coding genes, but also key TEs, including LINE1, Alu, and endogenous retroviruses, in both cisplatin-sensitive and -resistant cell lines. By co-expressing with downstream genes or by creating chimeric transcripts with host genes at their insertion sites, these TEs seem to control the expression of protein-coding genes, including tumor-related genes. Our model uncovers TEs influencing the expression of cancer genes and cancer pathways. Collectively, our findings indicate that TE alterations associated with cisplatin treatment occur in critical cancer genes and cellular pathways synergically. This research highlights the importance of considering the entire spectrum of transcribed elements in the genome, especially TE expression, for a complete understanding of complex models like cancer response to treatment.
Simultaneous Quantification of Vancomycin, Linezolid and Voriconazole in Human Plasma by UHPLC–MS/MS: Application in Therapeutic Drug Monitoring
Authors: Liu Yao , Li Yanan , Chen Wenli , Ming Dandan , Luo Wenji , Liang Jiabi
Published: May 2024

Objective

Individual differences challenge the treatment of vancomycin, linezolid and voriconazole in severe infections. This study aimed to build a simple and economical method for simultaneous determination of the three antibiotics in human plasma by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC–MS/MS) and provided a reference for therapeutic drug monitoring (TDM) of infected patients.

Methods

The plasma samples were precipitated by acetonitrile and detected and separated on a shim-pack GIST C18 column following the gradient elution within 5 min. Mass quantification was performed on multiple reaction monitoring mode under positive electrospray ionization.

Results

The linear ranges of vancomycin, linezolid and voriconazole were 1.00–100.00, 0.10–15.00 and 0.10–20.00 μg·mL−1, respectively, with good linearity (R2 > 0.99). The accuracy and precision, matrix effect, extraction recovery and stability were validated, and the results all meet the acceptance criteria of China Food and Drug Administration (CFDA) guidelines.

Conclusion

The UHPLC–MS/MS method was established and validated for the simultaneous determination of vancomycin, linezolid and voriconazole in human plasma and successfully applied to routine TDM for individualized treatment.
Do Judges in China Follow Wrongly Decided Precedents?—An Empirical Study
Authors: Qu Charles Zhen , Li Bin , Lin Lauren Yu-Hsin
Published: May 2024

Do Chinese judges follow prior decisions fraught with judicial errors? If they do, why do they do so? The development of policies on the reform of China’s judicial system requires an answer to these questions. Unfortunately, empirical findings that may lead to an answer, especially those based on data collected from case reports, are lacking. To fill this gap, we undertook an analysis of 310 case reports on a complex issue to discover (i) the influence of two wrongly decided precedents announced by the Supreme People’s Court and (ii) the extent to which the rank of the deciding court affects the force of this influence. Our findings suggest that judges may rely on an officially designated precedent even if the latter is wrongly decided and the strength of the influence is negatively correlated with the seniority of the deciding court. Our findings are useful for isolating factors affecting judicial decision making in China, which are necessary for making decisions on the reform of judicial system in that country.
Hardware Addition Over Finite Fields Based On Booth–Karatsuba Algorithm
Authors: Perez J Ayuso
Published: May 2024

Two algorithms, both based around multiplication, one defined by Andrew Donald Booth in 1950 and the other defined by Anatoly Alexeevitch Karatsuba in 1960 can be applied to other types of operations. We know from recent results that to perform some algebraic transformations it is more efficient to calculate an inverse effect of a smaller magnitude together with an original action with a higher rank, than the initial operation, reaching the final element with less transitions. In this paper, we present an addition algorithm on $\mathbb {Z}/m\mathbb {Z}$ of big-integer numbers based on these concepts, using an alternative to traditional hardware implementation for binary addition based on FULL-ADDER cells, allowing the reduction of space complexity compared with other techniques, such as carry-lookahead, letting us calculate a modular addition in an optimal order complexity of $\mathcal {O}(n)$ without adding more complexity due to reduction operations.
Faecal Transplantation for Ulcerative Colitis From Diet Conditioned Donors Followed by Dietary Intervention Results in Favourable Gut Microbial Profile Compared to Faecal Transplantation Alone
Authors: Leibovitzh Haim , Sarbagili Shabat Chen , Hirsch Ayal , Zittan Eran , Mentella Maria Chiara , Petito Valentina , Cohen Nathaniel Aviv , Ron Yulia , Fliss Isakov Naomi , Pfeffer Jorge , Yaakov Michal , Fanali Caterina , Turchini Laura , Masucci Luca , Quaranta Gianluca , Kolonimos Nitzan , Godneva Anastasia , Weinberger Adina , Scaldaferri Franco , Maharshak Nitsan
Published: May 2024

Background and Aims

Several faecal microbial transplantation [FMT] approaches for ulcerative colitis [UC] have been investigated with conflicting results. We have recently published the clinical outcomes from the CRAFT UC Trial using FMT with the UC Exclusion Diet [UCED], compared with FMT alone. Here we aimed to compare the two FMT strategies in terms of microbial profile and function.

Methods

Subjects recruited to the CRAFT UC study with available pre- and post-intervention faecal samples were included. Donors received diet conditioning for 14 days based on the UCED principles. Group 1 received single FMT by colonoscopy [Day 1] and enemas [Days 2 and 14] without donors’ dietary conditioning [N = 11]. Group 2 received FMT but with donors’ dietary pre-conditioning and UCED for the patients [N = 10]. Faecal samples were assessed by DNA shotgun metagenomic sequencing.

Results

Following diet conditioning, donors showed depletion in metabolic pathways involved in biosynthesis of sulphur-containing amino acids. Only Group 2 showed significant shifts towards the donors’ microbial composition [ADONIS: R2 = 0.15, p = 0.008] and significantly increased Eubacterium_sp_AF228LB post-intervention [β-coefficient 2.66, 95% confidence interval 2.1–3.3, q < 0.05] which was inversely correlated with faecal calprotectin [rho = −0.52, p = 0.035]. Moreover, pathways involved in gut inflammation and barrier function including branched chain amino acids were enriched post-intervention in Group 2 and were significantly inversely correlated with faecal calprotectin.

Conclusion

FMT from diet conditioned donors followed by the UCED led to microbial alterations associated with favourable microbial profiles which correlated with decreased faecal calprotectin. Our findings support further exploration of the additive benefit of dietary intervention for both donors and patients undergoing FMT as a potential treatment of UC.
Long-term prognostic significance of stress hyperglycemia in patients with ST-elevation myocardial infarction
Authors: Savic L , Mrdovic I , Asanin M , Krljanac G , Lasica R , Matic D , Simic D , Rajic D , Kastel B
Published: May 2024

Funding Acknowledgements

None.

Background/aim

Stress hyperglycemia is defined as hyperglycemia that occurs in critically ill patients without diabetes mellitus (DM). It is associated with adverse in-hospital outcomes in patients with ST elevation myocardial infarction (STEMI). The aim of the present study is to evaluate short- and long-term prognostic impact of stress hyperglycemia in STEMI patients.

Method

We analysed 2505 consecutive STEMI patients treated with successful primary PCI (pPCI) without previous DM and without cardiogenic shock at admission. Successful pPCI was defined as post-procedural flow TIMI 3. Stress hyperglycemia was defined as plasma glucose level above 7.8mmol/L at any time during hospitalization. The follow-up period was 6 years.

Results

Stress hyperglycemia at admission was registered in 685 (27.3%) patients. Compared with patients without stress hyperglycemia, patients with stress hyperglycemia were older and presented more often with heart failure (Killip class II and III); they were more likely to have hypertension, chronic kidney disease, three vessel coronary disease (at initial angiogram) and lower predischarge left ventricular ejection fraction (EF). In-hospital, 30-day and 6-year mortality were significantly higher in patients with stress hyperglycemia vs patients without stress hyperglycemia: 7.1% vs 1.5%, 7.5% vs 1.7% and 12.5% vs 4.6% (p<0.001), respectively as shown in Figure 1. In Cox regression analysis stress hyperglycemia was an independent predictor for in-hospital, 30-days and 6-year mortality- HR 2.19 (95% 1.49-3.94), p=0.018, HR 1,58(95%CI 1.15-2.85), p=0.020 and HR 1.52 (95%CI 1.32-2.17), p=0.030, respectively.

Conclusion

In STEMI patients without diabetes mellitus treated with successful primary PCI stress hyperglycemia is an independent predictor for short- and long-term mortality (up to 6-years). These findings emphasize the importance of close monitoring of blood glucose level in STEMI patients regardless of diabetic status.
Staged versus immediate complete vessel revascularization in patients presenting with ST-segment elevation myocardial infarction: a systematic review and meta-analysis
Authors: David B J , Valencia A E , Tugade R E , Castro R T
Published: May 2024

Funding Acknowledgements

None.

Introduction

In patients presenting with acute coronary syndrome (ACS) ST-segment elevation myocardial infarction (STEMI), percutaneous coronary intervention (PCI) is the preferred modality of reperfusion. However, these patients may also have multivessel coronary artery disease (CAD) on coronary angiography which is associated with higher risk of mortality. Current guidelines recommend complete revascularization in STEMI with multivessel CAD, however this poses a high risk for major acute cardiovascular events (MACE). Other available reperfusion strategies include staged vessel revascularization. This meta-analysis aims to determine if staged vessel revascularization can be a better mode of reperfusion strategy in patients with STEMI with multivessel CAD.

Methods

A comprehensive search of randomized controlled trials (RCT) was conducted with the use of staged versus immediate complete vessel revascularization in patients with STEMI. Outcome measures to assess the effectiveness of these techniques were all-cause mortality, MACE and target vessel revascularization. The analyses were done using random effects analysis model by mantel-haenszel statistical method via Review Manager V5.4.

Results

There were five studies included in the meta-analysis with 1,483 subjects analyzed. There was 26% less risk of all-cause mortality (RR 0.74 [95% CI: 0.41-1.31]) and 6% less risk for MACE (RR 0.94 [95% CI: 0.58-1.52]) in staged revascularization compared to immediate complete revascularization. In terms of target-vessel revascularization there was no statistical difference between the two treatment strategies (RR 1.02 [95% CI: 0.57-1.83]).

Conclusion

Staged and immediate complete vessel revascularization have similar rates of target-vessel revascularization among patients presenting with STEMI. However, staged vessel revascularization showed lower rates of all-cause mortality and MACE, which suggest that this treatment strategy may be a preferable type of revascularization in patients presenting with STEMI with multivessel CAD.
Long-term outcome after unprotected left main percutaneous coronary intervention in patients with acute myocardial infarction complicated by cardiogenic shock: a landmark analysis
Authors: Yatsu S , Ogita M , Singh Y S , Onozato T , Abe K , Shitara J , Endo H , Wada H , Miyauchi K , Suwa S
Published: May 2024

Funding Acknowledgements

None.

Background

Early revascularization of culprit arteries has demonstrated to improve outcomes in patients with acute myocardial infarction (AMI) complicated by cardiogenic shock (CS), however, little is known about long-term outcome after unprotected left main (LM) percutaneous coronary intervention (PCI) in patients with AMI-CS.

Methods

We retrospectively investigated 2325 consecutive patients with AMI who underwent primary percutaneous coronary intervention (pPCI) in our institution from January 2004 to December 2017. The primary outcome was cardiovascular (CV) death up to 3yrs.

Results

Among the 2325 eligible patients, 272 AMI patients (11.7%) were complicated by CS on admission (AMI-CS). The mean age was 71 years, 75% of patients were male, STEMI was seen in 86%, and mechanical circulatory support was used in 61%. Of 272 AMI-CS, 35 (14.0%) patients were treated with PCI for LM and had significantly higher 30-day cardiovascular mortality (52.6%) compared with those treated with PCI for non-LM (24.8%) (p = 0.0001). Kaplan-Meier analysis showed that mortality up to 3 years was significantly higher in AMI-CS patients with LM compared those with non-LM (p < 0.0001). Multivariate Cox regression analysis showed LM was significantly associated with higher cardiovascular mortality (adjusted HR 1.90, 95%CI 1.18-3.07, p = 0.0088).

Conclusions

Primary PCI of the LM was performed in 14.0% of patients with AMI-CS. Short- and long-term CV mortality was significantly higher with LM AMI-CS than non-LM AMI-CS. Further studies should evaluate to improve both short- and long-term outcome among AMI-CS with LM.
Combining rivaroxaban with aspirin for peripheral artery disease: an in-depth systematic review and meta-analysis
Authors: David B J , Valencia A E , Cheng F C
Published: May 2024

Funding Acknowledgements

None.

Introduction

Peripheral artery disease (PAD) poses a significant challenge in the realm of cardiovascular medicine, necessitating a multifaceted approach to mitigate its impact and enhance patient outcomes. One treatment approach involves the combined use of rivaroxaban, a direct oral anticoagulant, and aspirin, a commonly used antiplatelet agent in decreasing possible complications that can develop in patients with PAD.

Methods

An extensive search of randomized controlled trials (RCTs) comparing the efficacy of rivaroxaban in combination with aspirin versus aspirin monotherapy among individuals diagnosed with peripheral artery disease. The assessment of this treatment approach involved evaluating the following primary outcomes: a decrease in major adverse cardiovascular events (MACE) and the need for major amputation. Safety profile was also evaluated by examining the rate of major bleeding, utilizing the scoring tool from International Society of Thrombosis and Hemostasis (ISTH). The analyses were performed using a random effects analysis approach via Review Manager V5.4.

Results

This meta-analysis encompassed three studies involving a total of 9,352 participants. There was reduction of MACE in rivaroxaban with aspirin therapy (RR 0.83 [95% CI: 0.71-0.97] I2 = 29%, p = 0.02] but there was no significant difference in terms of major amputation rates (RR 0.96 [95% CI: 0.80-1.14] I2 = 0%, p = 0.62). However, there was increased risk of bleeding in rivaroxaban with aspirin therapy (RR 1.46 [95% CI: 1.17-1.82] I2=0, p = 0.0009) compared to aspirin alone.

Conclusion

Rivaroxaban combined with aspirin therapy demonstrated a 17% reduction in MACE compared with aspirin monotherapy but didn’t reduce major amputation rates. Also, doing this strategy poses a higher risk of bleeding. Therefore, a balance between the risks and benefits of this combined therapy necessitates a thorough assessment of individual patient profiles, considering factors such as overall cardiovascular risk, comorbidities, and bleeding tendencies. Further research and long-term studies are needed to establish comprehensive guidelines for the appropriate utilization of this combination therapy in various patient populations.
Pediatric Takotsubo cardiomyopathy: a review and insights from a national multicentric registry
Authors: Vazirani Ballesteros R , Rodriguez-Gonzalez M , Castellano-Martinez A , Andres M , Uribarri A , Corbi-Pascual M , Alfonso F , Blanco-Ponce E , Lluch-Requerey C , Fernandez-Cordon C , Almendro-Delia M , Vedia Cruz O , Nunez-Gil I
Published: May 2024

Funding Acknowledgements

None.

Background

Takotsubo syndrome (TTS) in the pediatric population is an infrequent but relevant cause of morbidity and mortality, with limited studies addressing its clinical course and prognosis.

Objectives

We aimed to analyze the clinical features and prognosis of pediatric TTS in a nation-wide multicenter registry and considering the published literature.

Methods

we included a total of 54 patients from 4 different hospitals in Spain, as well as pediatric TTS patients from the published literature. Comparisons between groups were performed in order to assess for statistically and clinically relevant prognostic differences between pediatric and adult population features.

Results

Comparison between the RETAKO general population is detailed in Table 1. Pediatric patients with TTS had a median age of 11 years (IQR = 4-14).

When compared to the RETAKO general population, they were more often male (51.9% vs 23.3%, p<0.001), and displayed a higher prevalence of secondary forms (90.7% vs 35.6% in adults, p<0.001). Regarding race, 11 cases (20.4%) were from Asia and 42 (77.8%) were Caucasian; whereas in RETAKO 1420 (94.9%) were Caucasians, with under 5 cases (<0.1%) being Asian.

Pediatric patients presented less commonly with angina (11.1% vs 64.1%, p<0.001) or dyspnea (30% vs 41.7%, p<0.001), compared to the general RETAKO cohort. Nevertheless, pediatric patients with TTS exhibited a higher Killip status on admission (Killip IV 74.1% vs 10.5%, p<0.001), and higher needs of vasoactive and mechanical ventilatory support during hospitalization.

Regarding complementary exams, pediatric patients presented with lower LVEF on admission (30.5+10.4 vs 36.9+16.9, p = 0.014) together with greater prevalence of atypical (basal or midventricular) TTS patterns on echocardiography (30.2% vs 15.8%, p = 0.006). Additionally, there were significantly less ST-segment alterations in the pediatric population (either ST-segment elevation or depression), without differences on T wave inversion in the admission ECG.

During follow-up, all-cause deaths (11.1% vs 12,5%, p = 0.761) and TTS recurrences (3.8% vs 3,8%, p = 0.863) were similar between groups.

Conclusions

TTS in the pediatric population presents a distinctive clinical profile, with higher prevalence of atypical symptoms and physical triggers; as well as higher rates of cardiogenic shock on admission and similar mortality and recurrence rates than those of the adult population. This study provides valuable insights into understanding pediatric TTS and underscored the necessity for further research in this age group.Table 1