bluuebunny/crossref_metadata_2025 huggingface dataset:
Parametric analysis, modeling and optimization of the process parameters in electric discharge machining of aluminium metal matrix composite
Authors: Kumar Harmesh , Wadhwa Amandeep Singh , Akhai Shalom , Kaushik Arishu
Published: May 2024

Optimizing electric discharge machining (EDM) for aluminum/SiCp metal matrix composites poses challenges due to intricate machine parameters and process complexity, impacting process economy and elevating product costs. The research aims to find the optimal combination of process parameters which include pulse on-time, pulse current, duty cycle (%), gap voltage, sensitivity and flushing pressure for EDM of Al/SiCp-MMC using a copper electrode for the selected response factors such as material erosion rate and surface roughness, Ra. The experiments were designed using the central composite design of response surface methodology and an advanced optimization technique known as Teaching–learning-based optimization (TLBO), is applied to find the optimal combination of process parameters to obtain maximum material erosion rate subject to the desired range of surface roughness (SR), Ra. The combination of the high pulse on-time (i.e. 150 μs) and high pulse current (i.e. 12A) results in high material removal rate with deep craters on the machined surface clearly visible in SEM images contrasting the minimized surface roughness at lower values of pulse on-time (50 μs) and the pulse current (4A). Pulse on - time (Ton) is found to be the most significant factor for material erosion rate and surface roughness with percentage contribution of 70.86 and 54.9 respectively for optimization of the response. The regression models were developed at 95% confidence level for material removal rate and surface roughness with R2 value of 0.93 and 0.95 respectively signifying high degree of accuracy in predicting the response. Confirmation tests conducted to check the adequacy of the established models revealed that the percentage error between the predicted and experimental responses is found to be within acceptable levels. Electron discharge machining of the aluminium metal matrix composite at the optimized conditions could provide economical aspect in the aerospace and automobile industry.
Interpolation of environmental data using deep learning and model inference
Authors: Ibebuchi Chibuike Chiedozie , Abu Itohan-Osa
Published: May 2024

The temporal resolution of environmental data sets plays a major role in the granularity of the information that can be derived from the data. In most cases, it is required that different data sets have a common temporal resolution to enable their consistent evaluations and applications in making informed decisions. This study leverages deep learning with long short-term memory (LSTM) neural networks and model inference to enhance the temporal resolution of climate datasets, specifically temperature, and precipitation, from daily to sub-daily scales. We trained our model to learn the relationship between daily and sub-daily data, subsequently applying this knowledge to increase the resolution of a separate dataset with a coarser (daily) temporal resolution. Our findings reveal a high degree of accuracy for temperature predictions, evidenced by a correlation of 0.99 and a mean absolute error of 0.21 °C, between the actual and predicted sub-daily values. In contrast, the approach was less effective for precipitation, achieving an explained variance of only 37%, compared to 98% for temperature. Further, besides the sub-daily interpolation of the climate data sets, we adapted our approach to increase the resolution of the Normalized difference vegetation index of Landsat (from 16 d to 5 d interval) using the LSTM model pre-trained from the Sentinel 2 Normalized difference vegetation index—that exists at a relatively higher temporal resolution. The explained variance between the predicted Landsat and Sentinel 2 data is 70% with a mean absolute error of 0.03. These results suggest that our method is particularly suitable for environmental datasets with less pronounced short-term variability, offering a promising tool for improving the resolution and utility of the data.
Autoencoders for discovering manifold dimension and coordinates in data from complex dynamical systems
Authors: Zeng Kevin , De Jesús Carlos E Pérez , Fox Andrew J , Graham Michael D
Published: May 2024

While many phenomena in physics and engineering are formally high-dimensional, their long-time dynamics often live on a lower-dimensional manifold. The present work introduces an autoencoder framework that combines implicit regularization with internal linear layers and L
2 regularization (weight decay) to automatically estimate the underlying dimensionality of a data set, produce an orthogonal manifold coordinate system, and provide the mapping functions between the ambient space and manifold space, allowing for out-of-sample projections. We validate our framework’s ability to estimate the manifold dimension for a series of datasets from dynamical systems of varying complexities and compare to other state-of-the-art estimators. We analyze the training dynamics of the network to glean insight into the mechanism of low-rank learning and find that collectively each of the implicit regularizing layers compound the low-rank representation and even self-correct during training. Analysis of gradient descent dynamics for this architecture in the linear case reveals the role of the internal linear layers in leading to faster decay of a ‘collective weight variable’ incorporating all layers, and the role of weight decay in breaking degeneracies and thus driving convergence along directions in which no decay would occur in its absence. We show that this framework can be naturally extended for applications of state-space modeling and forecasting by generating a data-driven dynamic model of a spatiotemporally chaotic partial differential equation using only the manifold coordinates. Finally, we demonstrate that our framework is robust to hyperparameter choices.
Structural formation yield of GeV centers from implanted Ge in diamond
Authors: Wahl Ulrich , Correia João Guilherme , Costa Ângelo , Lamelas Afonso , Amaral Vítor , Johnston Karl , Magchiels Goele , Tunhuma Shandirai Malven , Vantomme André , Pereira Lino M C
Published: May 2024

In order to study the structural formation yield of germanium-vacancy (GeV) centers from implanted Ge in diamond, we have investigated its lattice location by using the β
− emission channeling technique from the radioactive isotope 75Ge (t
1/2 = 83 min) produced at the ISOLDE/CERN facility. 75Ge was introduced via recoil implantation following 30 keV ion implantation of the precursor isotope 75Ga (126 s) with fluences around 2 × 1012–5 × 1013 cm−2. While for room temperature implantation fractions around 20% were observed in split-vacancy configuration and 45% substitutional Ge, following implantation or annealing up to 900 °C, the split-vacancy fraction dropped to 6%–9% and the substitutional fraction reached 85%–96%. GeV complexes thus show a lower structural formation yield than other impurities, with substitutional Ge being the dominant configuration. Moreover, annealing or high-temperature implantation seem to favor the formation of substitutional Ge over GeV. Our results strongly suggest that GeV complexes are thermally unstable and transformed to substitutional Ge by capture of mobile carbon interstitials, which is likely to contribute to the difficulties in achieving high formation yields of these optically active centers.
Minimality conditions for Sturm-Liouville problems with a boundary condition depending affinely or quadratically on an eigenparameter
Authors: Kerimov Nazim , Aliyev Yagub
Published: May 2024

In the paper we study Sturm-Liouville problems with a boundary condition depending affinely or quadratically on an eigenparameter. The necessary and sufficient conditions for minimality and completeness of the chosen system of root functions of the corresponding operator were given in two forms, one with the use of special associated functions and another one with the direct use of characteristic functions. This direct method was known for the affine case and was extensively discussed in the literature. The aim of the present paper is to develop this direct method for the quadratic case and to consider the affine and quadratic cases together in a unified way.
Invertible and noninvertible symbolic dynamics and their C*-algebras
Authors: Brix Kevin
Published: May 2024

This paper surveys the recent advances in the interactions between symbolic dynamics and C*-algebras. We explain how conjugacies and orbit equivalences of both two-sided (invertible) and one-sided (noninvertible) symbolic systems may be encoded into C*-algebras, and how the dynamical systems can be recovered from structure-preserving *-isomorphisms of C*-algebras. We have included many illustrative examples as well as open problems.
Advances in quantum permutation groups
Authors: Freslon Amaury
Published: May 2024

We survey several results, ranging over the past fifteen years, concerning the quantum permutation groups and their quantum subgroups around three themes: quantum information, dynamics, and probability theory. In each case, we try to be as self-contained as possible and convey some intuition concerning the role and importance of quantum permutations, as well as key ideas of the proofs.
Yearning to Submit
Authors: Frie Roger
Published: May 2024

This chapter traces the source of Fromm’s impassioned arguments against fascism in Escape From Freedom. With his arrival in New York in 1934, Fromm began a new chapter of his life as a German Jewish refugee. He watched from afar as the political situation in Europe deteriorated, ever conscious of the growing threat of Nazism for his family members, friends, and colleagues who remained in Germany. In 1938, Fromm traveled back to Europe for the first time. When the November Pogrom broke out, Fromm was convalescing in Switzerland from an attack of tuberculosis. In his weakened state, Fromm’s corresponded regularly with Horkheimer, and their letters reveal the depth of worry and doubt that Fromm felt as he sought to help his family members from the isolation of his hospital bed. When Fromm was finally well enough to return to the United States, he simultaneously engaged in a campaign to save his relatives and elaborated his arguments on the dangers of fascism, which would form the basis for Escape From Freedom. Fromm’s psychology of Nazism is examined and explained.
Confronting Genocide
Authors: Frie Roger
Published: May 2024

This chapter examines connections between the personal dimension of the Holocaust in Fromm’s life and his writings on the destructiveness and evil. The chapter sheds new light on Fromm’s marriage to Henny Gurland, a fellow German Jewish refugee, who accompanied the philosopher Walter Benjamin on his fateful attempt to flee Nazi-occupied France and on Fromm’s rescue of his cousin, Heinz Brandt, who had remarkably survived Auschwitz and was imprisoned by the East German secret police. Throughout the postwar years, the Holocaust correspondence forms the unspoken context for Fromm’s impassioned stance on human solidarity. At the height of the civil rights movement, Fromm spoke directly to the scourge of racism. In The Anatomy of Human Destructiveness, he analyzed the personal pathologies of Hitler and Himmler at the heart of the “Final Solution.” Fromm struggled to bridge his early life experiences in Germany with the reality of antisemitism; called out ambivalent postwar German commitments to remembrance and responsibility; and sought to understand the motivations of major Nazi figures like Albert Speer. At the end of his life, he offered a series of critical reflections on Zionism and Israel.
Understanding individual experiences with stick-built and modular cleanrooms: Lessons learned and a call to action
Authors: Armistead Lori T , Eckel Stephen F
Published: May 2024

Purpose

The purpose of this study was to assess the real-world experiences of cleanroom managers and specialists who have designed, installed, and maintained stick-built and/or modular cleanrooms, delineate the advantages and disadvantages of each type of cleanroom, and gather sterile compounding cleanroom design and installation advice and lessons learned.

Methods

This study was conducted via surveys and semistructured interviews of individuals with cleanroom experience in the previous 5 years. Qualitative analyses were conducted on participants’ survey and interview responses to assess their satisfaction with each type of cleanroom and to determine what they perceive to be the pros and cons of each type based on their own experiences. Key lessons learned and advice from these individuals were also extracted from their survey and interview responses.

Results

Fourteen individuals from 13 US states completed the survey; 12 participated in follow-up interviews. Fifty percent of the participants (n = 7) had installed 5 or more cleanrooms in the previous 5 years and over half (n = 8; 57%) had 7 or more years of cleanroom experience. The average satisfaction scores for each type of cleanroom, on a 1 to 10 scale, was 5.3 for stick-built (n = 11) and 9.3 for modular (n = 4). The pros of stick-built cleanrooms included greater design and material flexibility and lower up-front costs. The pros of modular cleanrooms included the cleanroom experience and expertise of modular vendors, quick and easy installations, guaranteed certification, and high-quality and durable design features and materials. Additionally, modular cleanrooms had fewer long-term maintenance issues, greater long-term flexibility, and lower indirect and long-term costs than stick-built cleanrooms. Key pieces of advice from the participants included the following: do your homework before beginning a cleanroom project; make sure heating, ventilation, and air conditioning system(s) and air handlers are adequate for your needs; and remember that the ultimate purpose of a quality cleanroom is patient safety. Participants also advocated for industry-wide cleanroom standards that go beyond USP regulations.

Conclusion

The findings of this study confirm many of the purported pros and cons of each type of cleanroom, with further insight gained into the relative quality and costs of each type. Modular cleanrooms were considered by most participants to be a better long-term option, based on quality and lifetime costs, if feasible to install. Study participants also emphasized that designing and installing pharmacy cleanrooms is a complex and time-intensive process that often comes with a steep learning curve. While there are federal and state cleanroom standards available and consultants for hire, a comprehensive resource or manual that could provide guidance, insight, and collective lessons learned on cleanroom design and installation is needed.
II—Ownership, Property and Belonging: Some Lessons to Learn from Thinkers of Antiquity about Economics and Success
Authors: Rowett Catherine
Published: May 2024

I explore some enlightening alternative economic theories in Plato’s Republic which help to cast doubt on standard models of rationality in economics. Starting from Socrates’ suggestion that things work best if everyone says ‘mine’ about the same things, I discuss a kind of ‘belonging’ which merits more attention in political and economic theory. This kind of belonging is not about owning property, but it can (better) explain the desire to do things for others and for the collective good. But did Socrates forget to invoke it when addressing the puzzle about why the philosopher would willingly return to the cave?
Transcriptome analysis: a powerful tool to understand individual microbial behaviors and interactions in ecosystems
Authors: Sato Yuya
Published: May 2024

Transcriptome analysis is a powerful tool for studying microbial ecology, especially individual microbial functions in an ecosystem and their interactions. With the development of high-throughput sequencing technology, great progress has been made in analytical methods for microbial communities in natural environments. 16S rRNA gene amplicon sequencing (ie microbial community structure analysis) and shotgun metagenome analysis have been widely used to determine the composition and potential metabolic capability of microorganisms in target environments without requiring culture. However, even if the types of microorganisms present and their genes are known, it is difficult to determine what they are doing in an ecosystem. Gene expression analysis (transcriptome analysis; RNA-seq) is a powerful tool to address these issues. The history and basic information of gene expression analysis, as well as examples of studies using this method to analyze microbial ecosystems, are presented.
Direct and indirect treatment effects in the presence of semicompeting risks
Authors: Deng Yuhao , Wang Yi , Zhou Xiao-Hua
Published: May 2024

Semicompeting risks refer to the phenomenon that the terminal event (such as death) can censor the nonterminal event (such as disease progression) but not vice versa. The treatment effect on the terminal event can be delivered either directly following the treatment or indirectly through the nonterminal event. We consider 2 strategies to decompose the total effect into a direct effect and an indirect effect under the framework of mediation analysis in completely randomized experiments by adjusting the prevalence and hazard of nonterminal events, respectively. They require slightly different assumptions on cross-world quantities to achieve identifiability. We establish asymptotic properties for the estimated counterfactual cumulative incidences and decomposed treatment effects. We illustrate the subtle difference between these 2 decompositions through simulation studies and two real-data applications in the Supplementary Materials.
Testing conditional quantile independence with functional covariate
Authors: Feng Yongzhen , Li Jie , Song Xiaojun
Published: May 2024

We propose a new non-parametric conditional independence test for a scalar response and a functional covariate over a continuum of quantile levels. We build a Cramer–von Mises type test statistic based on an empirical process indexed by random projections of the functional covariate, effectively avoiding the “curse of dimensionality” under the projected hypothesis, which is almost surely equivalent to the null hypothesis. The asymptotic null distribution of the proposed test statistic is obtained under some mild assumptions. The asymptotic global and local power properties of our test statistic are then investigated. We specifically demonstrate that the statistic is able to detect a broad class of local alternatives converging to the null at the parametric rate. Additionally, we recommend a simple multiplier bootstrap approach for estimating the critical values. The finite-sample performance of our statistic is examined through several Monte Carlo simulation experiments. Finally, an analysis of an EEG data set is used to show the utility and versatility of our proposed test statistic.
Pattern of recurrence after stereotactic body radiotherapy of nodal lesions: a single-institution analysis
Authors: Ferro Milena , Macchia Gabriella , Pezzulla Donato , Cilla Savino , Romano Carmela , Ferro Marica , Boccardi Mariangela , Bonome Paolo , Picardi Vincenzo , Buwenge Milly , Morganti Alessio G , Deodato Francesco
Published: May 2024

Objectives

Stereotactic body radiotherapy (SBRT) and/or single fraction stereotactic body radiosurgery (SRS) are effective treatment options for the treatment of oligometastatic disease of lymph nodes. Despite the encouraging local control rate, progression-free survival remains unfair due to relapses that might occur in the same district or at other sites. The recurrence pattern analysis after nodal local ablative RT (laRT) in oligometastatic patients is presented in this study.

Methods

The pattern of failure of patients with nodal metastases who were recruited and treated with SBRT in the Destroy-1 or SRS in the Destroy-2 trials was investigated in this single-institution, retrospective analysis. The different relapsed sites following laRT were recorded.

Results

Data on 190 patients who received SBRT or SRS on 269 nodal lesions were reviewed. A relapse rate of 57.2% (154 out of 269 nodal lesions) was registered. The pattern of failure was distant in 88 (57.4%) and loco-regional in 66 (42.6%) patients, respectively. The most frequent primary malignancies among patients experiencing loco-regional failure were genitourinary and gynaecological cancers. Furthermore, the predominant site of loco-regional relapse (62%) was the pelvic area. Only 26% of locoregional relapses occurred contra laterally, with 74% occurring ipsilaterally.

Conclusions

The recurrence rates after laRT for nodal disease were more frequent in distant regions compared to locoregional sites. The most common scenarios for locoregional relapse appear to be genitourinary cancer and the pelvic site. In addition, recurrences often occur in the same nodal station or in a nodal station contiguous to the irradiated nodal site.

Advances in knowledge

Local ablative radiotherapy is an effective treatment in managing nodal oligometastasis. Despite the high local control rate, the progression free survival remains dismal with recurrences that can occur both loco-regionally or at distance. To understand the pattern of failure could aid the physicians to choose the best treatment strategy. This is the first study that reports the recurrence pattern of a significant number of nodal lesions treated with laRT.
A Quasi-Experimental Evaluation of the Lifelong Links Intervention for Reducing Homelessness amongst Care Leavers
Authors: Sanders Michael , Hirneis Vanessa , Picker Vanessa
Published: May 2024

Despite the fact that care leavers are at significantly higher risk of homelessness than their peers who have not experienced care, there is a paucity of information on evidence-based interventions to address this risk. Lifelong Links is a program developed and delivered by the Family Rights Group in England. The intervention aims to ensure that a child in care has a positive support network around them to help during their time in care and into adulthood. In this article, we analyse the outcomes of a quasi-experimental evaluation of the Lifelong Links program. Specifically, we make use of a combination of coarsened exact matching, and a triple-differences approach (or difference in difference in differences analysis). Results of our analyses show that Lifelong Links is associated with a reduction in the risk of becoming homeless for care leavers aged eighteen to twenty in the years following its implementation. Our most robust model showed a reduction of around 10 per cent in the risk of a young care leaver being deemed at risk of, or experiencing homelessness, suggesting that improving ties between young people in care and their birth families (and/or building other sources of support) could have beneficial impacts on housing outcomes into adulthood.
Altered static and dynamic cerebellar-cerebral functional connectivity in acute pontine infarction
Authors: Wei Ying , Wang Peipei , Zhang Yong , Miao Peifang , Liu Jingchun , Wei Sen , Wang Xin , Wang Yingying , Wu Luobing , Han Shaoqiang , Wei Yarui , Wang Kaiyu , Cheng Jingliang , Wang Caihong
Published: May 2024

This study investigates abnormalities in cerebellar-cerebral static and dynamic functional connectivity among patients with acute pontine infarction, examining the relationship between these connectivity changes and behavioral dysfunction. Resting-state functional magnetic resonance imaging was utilized to collect data from 45 patients within seven days post-pontine infarction and 34 normal controls. Seed-based static and dynamic functional connectivity analyses identified divergences in cerebellar-cerebral connectivity features between pontine infarction patients and normal controls. Correlations between abnormal functional connectivity features and behavioral scores were explored. Compared to normal controls, left pontine infarction patients exhibited significantly increased static functional connectivity within the executive, affective-limbic, and motor networks. Conversely, right pontine infarction patients demonstrated decreased static functional connectivity in the executive, affective-limbic, and default mode networks, alongside an increase in the executive and motor networks. Decreased temporal variability of dynamic functional connectivity was observed in the executive and default mode networks among left pontine infarction patients. Furthermore, abnormalities in static and dynamic functional connectivity within the executive network correlated with motor and working memory performance in patients. These findings suggest that alterations in cerebellar-cerebral static and dynamic functional connectivity could underpin the behavioral dysfunctions observed in acute pontine infarction patients.
Switching off: disruptive TMS reveals distinct contributions of the posterior middle temporal gyrus and angular gyrus to bilingual speech production
Authors: Timofeeva Polina , Finisguerra Alessandra , D’Argenio Giulia , García Adolfo M , Carreiras Manuel , Quiñones Ileana , Urgesi Cosimo , Amoruso Lucia
Published: May 2024

The role of the left temporoparietal cortex in speech production has been extensively studied during native language processing, proving crucial in controlled lexico-semantic retrieval under varying cognitive demands. Yet, its role in bilinguals, fluent in both native and second languages, remains poorly understood. Here, we employed continuous theta burst stimulation to disrupt neural activity in the left posterior middle-temporal gyrus (pMTG) and angular gyrus (AG) while Italian–Friulian bilinguals performed a cued picture-naming task. The task involved between-language (naming objects in Italian or Friulian) and within-language blocks (naming objects [“knife”] or associated actions [“cut”] in a single language) in which participants could either maintain (non-switch) or change (switch) instructions based on cues. During within-language blocks, cTBS over the pMTG entailed faster naming for high-demanding switch trials, while cTBS to the AG elicited slower latencies in low-demanding non-switch trials. No cTBS effects were observed in the between-language block. Our findings suggest a causal involvement of the left pMTG and AG in lexico-semantic processing across languages, with distinct contributions to controlled vs. “automatic” retrieval, respectively. However, they do not support the existence of shared control mechanisms within and between language(s) production. Altogether, these results inform neurobiological models of semantic control in bilinguals.
Surface structural transformation and adsorption performance of poly(triazine imide)
Authors: Yu Gege , Zhao Yubao
Published: May 2024

Poly(triazine imide) synthesized by the molten salt route with incorporation of Li+ and Cl‒ ions (PTI/Li+Cl−) was prepared by rational controlling of the washing extent. The surface transformation of the phase-pure PTI framework incurred by thorough washing has been confirmed by a systematic analysis based on x-ray diffraction, Ultraviolet Raman, atomic force microscope, and x-ray photoelectron spectroscopy measurements. Uranyl ion adsorption experiments further support the surface structural transformation from triazine-unit PTI to heptazine-based graphitic carbon nitride. Efforts on the exploration of PTI material application should be mainly directed toward the waterless fields to give good repeatability.
High Prevalence of Unconfirmed Positive HIV Polymerase Chain Reaction Test Results Among African Infants With HIV Exposure in the International Epidemiology Databases to Evaluate AIDS Consortium
Authors: Carlucci James G , Huntington Thomas , Technau Karl-Günter , Yotebieng Marcel , Leroy Valériane , Anderson Kim , Amorissani-Folquet Madeleine , Wools-Kaloustian Kara , Edmonds Andrew
Published: May 2024

In a large, multiregional cohort of African infants with human immunodeficiency virus (HIV) exposure, 44% of those with a positive HIV polymerase chain reaction test lacked a confirmatory positive test. Efforts are needed to ensure high-fidelity implementation of HIV testing algorithms so that all positive results are confirmed.
A 44-year-old man with recurrent ST-segment elevation: a case report of two presentations of Granulomatosis with Polyangiitis
Authors: Cheng Kevin , de Silva Ranil
Published: May 2024

Background

Granulomatosis with Polyangiitis (GPA) is a rare multi-system autoimmune disorder that may present with cardiac manifestations that are often under-recognized. In this report, we discuss a usual case of a patient who presented as a cardiac emergency with recurrent ST elevation and discuss the approach and management.

Case summary

A 44-year-old man presented with two episodes of chest pain associated with ST-segment elevation on 12-lead ECG. Under investigation over the past several weeks for fatigue, nasal congestion, and red eyes, his first presentation was associated with widespread ST-segment elevation and an echogenic myocardium suggestive of myocarditis that was confirmed on cardiac MRI. A week later, the development of chest pain, antero-lateral ST elevation, and regional wall motion abnormalities suggested an acute coronary syndrome and he proceeded to primary percutaneous intervention that treated a lesion in the distal left anterior descending artery secondary to coronary arteritis. Diagnosed with GPA, he was started on immunosuppression and has had a resolution of his cardiac involvement at follow-up.

Discussion

This case report describes an unusual case of myocarditis and coronary arteritis presenting acutely in the same patient and emphasizes the importance of considering systemic autoimmune conditions when encountering primarily cardiac presentations. Early recognition and diagnosis of cardiac involvement will improve the long-term outcomes in these patients.
Effectiveness of directional coronary atherectomy in treating recurrent in-stent restenosis: a case report
Authors: Naniwa Shota , Tsuda Shigeyasu , Nakazawa Gaku , Yamada Shinichiro
Published: May 2024

Background

In-stent restenosis (ISR) remains a significant clinical problem. It is estimated that 10–20% of patients who develop a first event of ISR will develop recurrent ISR (R-ISR). However, the pathology of R-ISR remains largely unknown, and recommendations for its optimal management are lacking. In this case report, we discuss the effectiveness of directional coronary atherectomy (DCA) as an atherectomy device and the mechanism of R-ISR based on pathological findings obtained from DCA.

Case summary

We report the case of a 62-year-old man with a history of ST-segment elevation myocardial infarction treated with percutaneous coronary intervention (PCI) to the mid left circumflex artery using a bare metal stent. Even after the introduction of adequate secondary prevention therapy for ISR, the patient underwent a total of six PCI sessions over 10 years following primary PCI for R-ISR. Eventually, the decision was made to institute treatment with DCA and a drug-coated balloon. No symptoms of restenosis were observed over the following 4 years.

Discussion

In this case report, we demonstrate the effectiveness of DCA treatment for debulking a wide range of collagen-rich plaques and show that DCA treatment should be considered for the treatment of R-ISR.
Comparing flow and pulmonary artery growth post-patent ductus arteriosus stenting in patients with ductal-dependent pulmonary flow using 4D magnetic resonance imaging
Authors: Al Kindi Faiza A , Al Kindi Hamood , Maddali Madan Mohan , Al Farqani Abdullah , Al Alawi Khalid , Al Balushi Abdullah , Al Ghafri Mohammed , Khalil Sahar , Kumar Satish
Published: May 2024

Aims

The 4D magnetic resonance imaging (4D-flow MRI) provides a qualitative and quantitative assessment of cardiovascular structures and processes. 4D-flow MRI was used to study pulmonary flow in post-patent ductus arteriosus (PDA) stent insertion in duct-dependent pulmonary flow neonates at baseline (PDA stent insertion) and after 6 months, and also, to evaluate the effect of flow dynamics on the growth of pulmonary arteries (PAs).

Methods and results

This prospective observational study included neonates with ductus arteriosus-dependent pulmonary circulation who underwent ductal stenting between June 2021 and November 2022. Cardiac 4D-flow MRI and magnetic resonance angiography were conducted in two phases; after the deployment of the PDA stent during the neonatal period and after 6 months from stent deployment. Eight neonates were recruited, but only five completed both scans. A total of 10 PAs were evaluated during each phase. The median left PA (LPA) and right PA (RPA) diameters and indexed flow for LPA and RPA were evaluated. The growth rate of LPA was observed to be lower than that of RPA (percentage diameter increase: 74 vs. 153%). LPA Z-score was lower than RPA. Indexed flow in both LPA and RPA showed a reduction in the 6-month scan, which was consistent with reduced stent patency.

Conclusion

4D-flow cardiac MRI showed different growth rates and reduced flow between LPA and RPA post-PDA stent. These insights can aid in future management decisions.
Transcatheter aortic valve implantation in low-risk tricuspid or bicuspid aortic stenosis: the NOTION-2 trial
Authors: Jørgensen Troels Højsgaard , Thyregod Hans Gustav Hørsted , Savontaus Mikko , Willemen Yannick , Bleie Øyvind , Tang Mariann , Niemela Matti , Angerås Oskar , Gudmundsdóttir Ingibjörg J , Sartipy Ulrik , Dagnegaard Hanna , Laine Mika , Rück Andreas , Piuhola Jarkko , Petursson Petur , Christiansen Evald H , Malmberg Markus , Olsen Peter Skov , Haaverstad Rune , Sondergaard Lars , De Backer Ole ,   for the NOTION-2 investigators, Jørgensen Troels Højsgaard , De Backer Ole , Søndergaard Lars , Dagnegaard Hanna , Olsen Peter Skov , Bleie Øyvind , Haarverstad Rune , Savontaus Mikko , Malmberg Markus , Christiansen Evald Høj , Tang Mariann , Niemelä Matti , Ahvenvaara Tuomas , Guðmundsdóttir Ingibjörg , Myrdal Gunnar , Angerås Oskar , Petursson Petur , Laine Mika , Vähäsilta Tommi , Rück Andreas , Sartipy Ulrik
Published: May 2024

Background and Aims

Transcatheter aortic valve implantation (TAVI) has become the first choice to treat older patients with severe symptomatic aortic stenosis (AS). This study aimed to compare TAVI with surgery in low-risk patients ≤75 years of age, including both tricuspid and bicuspid AS.

Methods

The Nordic Aortic Valve Intervention (NOTION)-2 trial enrolled and 1:1 randomized low-risk patients aged ≤75 years with severe symptomatic AS to TAVI or surgery. The primary endpoint was a composite of all-cause mortality, stroke, or rehospitalization (related to the procedure, valve, or heart failure) at 12 months.

Results

A total of 370 patients were enrolled with a mean age of 71.1 years and a median Society of Thoracic Surgeons risk score of 1.1%. A total of 100 patients had bicuspid AS. The 1-year incidence of the primary endpoint was 10.2% in the TAVI group and 7.1% in the surgery group [absolute risk difference 3.1%; 95% confidence interval (CI), −2.7% to 8.8%; hazard ratio (HR) 1.4; 95% CI, 0.7–2.9; P = .3]. Patients with TAVI, when compared to surgery, had lower risk of major bleeding and new-onset atrial fibrillation and higher risk of non-disabling stroke, permanent pacemaker implantation, and moderate or greater paravalvular regurgitation. The risk of the primary composite endpoint was 8.7% and 8.3% in patients with tricuspid AS (HR 1.0; 95% CI, 0.5–2.3) and 14.3% and 3.9% in patients with bicuspid AS (HR 3.8; 95% CI, 0.8–18.5) treated with TAVI or surgery, respectively (P for interaction = .1).

Conclusions

Among low-risk patients aged ≤75 years with severe symptomatic AS, the rate of the composite of death, stroke, or rehospitalization at 1 year was similar between TAVI and surgery. Transcatheter aortic valve implantation outcomes in young bicuspid AS patients warrant caution and should be further investigated. (NOTION-2, ClinicalTrials.gov, NCT02825134).

Trial Registration number

ClinicalTrials.gov NCT02825134.
Pre- and post-procedural cardiac imaging (computed tomography and magnetic resonance imaging) in electrophysiology: a clinical consensus statement of the European Heart Rhythm Association and European Association of Cardiovascular Imaging of the European Society of Cardiology
Authors: Deneke Thomas , Kutyifa Valentina , Hindricks Gerhard , Sommer Philipp , Zeppenfeld Katja , Carbucicchio Corrado , Pürerfellner Helmut , Heinzel Frank R , Traykov Vassil B , De Riva Marta , Pontone Gianluca , Lehmkuhl Lukas , Haugaa Kristina , Sarkozy Andrea , Gimelli Alessia , Tondo Claudio , Ernst Sabine , Antz Matthias , Westwood Mark
Published: May 2024

Imaging using cardiac computed tomography (CT) or magnetic resonance (MR) imaging has become an important option for anatomic and substrate delineation in complex atrial fibrillation (AF) and ventricular tachycardia (VT) ablation procedures. Computed tomography more common than MR has been used to detect procedure-associated complications such as oesophageal, cerebral, and vascular injury. This clinical consensus statement summarizes the current knowledge of CT and MR to facilitate electrophysiological procedures, the current value of real-time integration of imaging-derived anatomy, and substrate information during the procedure and the current role of CT and MR in diagnosing relevant procedure-related complications. Practical advice on potential advantages of one imaging modality over the other is discussed for patients with implanted cardiac rhythm devices as well as for planning, intraprocedural integration, and post-interventional management in AF and VT ablation patients. Establishing a team of electrophysiologists and cardiac imaging specialists working on specific details of imaging for complex ablation procedures is key. Cardiac magnetic resonance (CMR) can safely be performed in most patients with implanted active cardiac devices. Standard procedures for pre- and post-scanning management of the device and potential CMR-associated device malfunctions need to be in place. In VT patients, imaging—specifically MR—may help to determine scar location and mural distribution in patients with ischaemic and non-ischaemic cardiomyopathy beyond evaluating the underlying structural heart disease. Future directions in imaging may include the ability to register multiple imaging modalities and novel high-resolution modalities, but also refinements of imaging-guided ablation strategies are expected.
Matreex: Compact and Interactive Visualization for Scalable Studies of Large Gene Families
Authors: Rossier Victor , Train Clement , Nevers Yannis , Robinson-Rechavi Marc , Dessimoz Christophe
Published: May 2024

Studying gene family evolution strongly benefits from insightful visualizations. However, the ever-growing number of sequenced genomes is leading to increasingly larger gene families, which challenges existing gene tree visualizations. Indeed, most of them present users with a dilemma: display complete but intractable gene trees, or collapse subtrees, thereby hiding their children's information. Here, we introduce Matreex, a new dynamic tool to scale up the visualization of gene families. Matreex's key idea is to use “phylogenetic” profiles, which are dense representations of gene repertoires, to minimize the information loss when collapsing subtrees. We illustrate Matreex's usefulness with three biological applications. First, we demonstrate on the MutS family the power of combining gene trees and phylogenetic profiles to delve into precise evolutionary analyses of large multicopy gene families. Second, by displaying 22 intraflagellar transport gene families across 622 species cumulating 5,500 representatives, we show how Matreex can be used to automate large-scale analyses of gene presence–absence. Notably, we report for the first time the complete loss of intraflagellar transport in the myxozoan Thelohanellus kitauei. Finally, using the textbook example of visual opsins, we show Matreex's potential to create easily interpretable figures for teaching and outreach. Matreex is available from the Python Package Index (pip install Matreex) with the source code and documentation available at https://github.com/DessimozLab/matreex.
Internet Use and Loneliness Among Urban and Non-Urban Chinese Older Adults: The Roles of Family Support, Friend Support, and Social Participation
Authors: Zhang Kunyu , Burr Jeffrey A , Mutchler Jan E , Lu Jiehua
Published: May 2024

Objectives

This study investigated the association between internet use and loneliness among older Chinese adults, and the mediating effects of family support, friend support, and social participation. These associations were evaluated in the context of urban and non-urban geographic settings.

Methods

This study used data from the 2018 wave of the China Longitudinal Ageing Social Survey (N = 10,126), examining samples of urban (n = 3,917) and non-urban (n = 6,209) older adults separately. Linear regression and path analysis within a structural equation modeling framework were employed.

Results

Internet use was negatively associated with loneliness for both urban and non-urban residing older adults. Family support and social participation mediated the association between internet use and loneliness for both urban and non-urban residing older Chinese adults, but friend support mediated this association only for urban older residents.

Discussion

This study shed light on our understanding of the relationship between internet use and loneliness among older adults in the Chinese context. Also, these findings suggested that digital interventions for loneliness should pay special attention to the different characteristics of urban and non-urban dwelling older Chinese adults.
Antenatal care coverage and early childhood mortality in Zimbabwe: new interpretations from nationally representative household surveys
Authors: Musiwa Anthony Shuko , Sinha Vandna , Hanley Jill , Ruiz-Casares Mónica
Published: May 2024

Zimbabwe has implemented universal antenatal care (ANC) policies since 1980 that have significantly contributed to improvements in ANC access and early childhood mortality rates. However, Demographic and Health Surveys (DHS) and Multiple Indicator Cluster Surveys (MICS), two of Zimbabwe’s main sources of health data and evidence, often provide seemingly different estimates of ANC coverage and under-five mortality rates. This creates confusion that can result in disparate policies and practices, with potential negative impacts on mother and child health in Zimbabwe. We conducted a comparability analysis of multiple DHS and MICS datasets to enhance the understanding of point estimates, temporal changes, rural–urban differences and reliability of estimates of ANC coverage and neonatal, infant and under-five mortality rates (NMR, IMR and U5MR, separately) from 2009 to 2019 in Zimbabwe. Our two samples z-tests revealed that both DHS and MICS indicated significant increases in ANC coverage and declines in IMR and U5MR but only from 2009 to 2015. NMR neither increased nor declined from 2009 to 2019. Rural–urban differences were significant for ANC coverage (2009–15 only) but not for NMR, IMR and U5MR. We found that there is a need for more precise DHS and MICS estimates of urban ANC coverage and all estimates of NMR, IMR and U5MR, and that shorter recall periods provide more reliable estimates of ANC coverage in Zimbabwe. Our findings represent new interpretations and clearer insights into progress and gaps around ANC coverage and under-five mortality rates that can inform the development, implementation, monitoring and evaluation of policy and practice responses and further research in Zimbabwe.
Lymphatic endothelial cell-specific NRAS p.Q61R mutant embryos show abnormal lymphatic vessel morphogenesis
Authors: Nozawa Akifumi , Abe Taiki , Niihori Tetsuya , Ozeki Michio , Aoki Yoko , Ohnishi Hidenori
Published: May 2024

Generalized lymphatic anomaly (GLA) and kaposiform lymphangiomatosis (KLA) are rare congenital disorders that arise through anomalous embryogenesis of the lymphatic system. A somatic activating NRAS p.Q61R variant has been recently detected in GLA and KLA tissues, suggesting that the NRAS p.Q61R variant plays an important role in the development of these diseases. To address this role, we studied the effect of the NRAS p.Q61R variant in lymphatic endothelial cells (LECs) on the structure of the lymphatics during embryonic and postnatal lymphangiogenesis applying inducible, LEC-specific NRAS p.Q61R variant in mice. Lox-stop-Lox NrasQ61R mice were crossed with Prox1-CreERT2 mice expressing tamoxifen-inducible Cre recombinase specifically in LECs. Whole-mount immunostaining of embryonic back skin using an antibody against the LEC surface marker VEGFR3 showed considerably greater lymphatic vessel width in LEC-specific NRAS p.Q61R mutant embryos than in littermate controls. These mutant embryos also showed a significant reduction in the number of lymphatic vessel branches. Furthermore, immunofluorescence staining of whole-mount embryonic back skin using an antibody against the LEC-specific nuclear marker Prox1 showed a large increase in the number of LECs in LEC-specific NRAS p.Q61R mutants. In contrast, postnatal induction of the NRAS p.Q61R variant in LECs did not cause abnormal lymphatic vessel morphogenesis. These results suggest that the NRAS p.Q61R variant in LECs plays a role in development of lymphatic anomalies. While this model does not directly reflect the human pathology of GLA and KLA, there are overlapping features, suggesting that further study of this model may help in studying GLA and KLA mechanisms.
Genetic and epigenetic signatures for improved breeding of cultivated blueberry
Authors: Wang Zejia , Zhang Wanchen , Zhou Yangyan , Zhang Qiyan , Kulkarni Krishnanand P , Melmaiee Kalpalatha , Tian Youwen , Dong Mei , Gao Zhaoxu , Su Yanning , Yu Hong , Xu Guohui , Li Yadong , He Hang , Liu Qikun , Sun Haiyue
Published: May 2024

Blueberry belongs to the Vaccinium genus and is a highly popular fruit crop with significant economic importance. It was not until the early twentieth century that they began to be domesticated through extensive interspecific hybridization. Here, we collected 220 Vaccinium accessions from various geographical locations, including 154 from the United States, 14 from China, eight from Australia, and 29 from Europe and other countries, comprising 164 Vaccinium corymbosum, 15 Vaccinium ashei, 10 lowbush blueberries, seven half-high blueberries, and others. We present the whole-genome variation map of 220 accessions and reconstructed the hundred-year molecular history of interspecific hybridization of blueberry. We focused on the two major blueberry subgroups, the northern highbush blueberry (NHB) and southern highbush blueberry (SHB) and identified candidate genes that contribute to their distinct traits in climate adaptability and fruit quality. Our analysis unveiled the role of gene introgression from Vaccinium darrowii and V. ashei into SHB in driving the differentiation between SHB and NHB, potentially facilitating SHB’s adaptation to subtropical environments. Assisted by genome-wide association studies, our analysis suggested VcTBL44 as a pivotal gene regulator governing fruit firmness in SHB. Additionally, we conducted whole-genome bisulfite sequencing on nine NHB and 12 SHB cultivars, and characterized regions that are differentially methylated between the two subgroups. In particular, we discovered that the β-alanine metabolic pathway genes were enriched for DNA methylation changes. Our study provides high-quality genetic and epigenetic variation maps for blueberry, which offer valuable insights and resources for future blueberry breeding.