bluuebunny/crossref_metadata_2025 huggingface dataset:
Photonic Generation of Chirp-Rate-Tunable Microwave Waveforms Using Temporal Cavity Solitons with Agile Repetition Rate
Authors: Xiong Wen-Hao , Yao Chuan-Fei , Li Ping-Xue , Zhu Fei-Yu , Lei Ruo-Nan
Published: April 2023

Chirp-rate-tunable microwave waveforms (CTMWs) with dynamically tunable parameters are of basic interest to many practical applications. Recently, photonic generation of microwave signals has made their bandwidths wider and more convenient for optical fiber transmission. An all-optical method for generation of multiband CTMWs is proposed and demonstrated on all-fiber architecture, relying on dual temporal cavity solitons with agile repetition rate. In the experiment, the triangular optical chirp microwave waveforms with bandwidth above 0.45 GHz (ranging from 1.45 GHz to 1.9 GHz) are obtained, and the chirp rate reaches 0.9 GHz/ms. The reconfigurability is also demonstrated by adjusting the control signal. This all-optical approach provides a technical basis for compact, multi-band reconfigurable microwave photonics transmission and reception systems.
Dynamics of spatially confined ns laser induced atmospheric air plasma and shock waves: visualization vis-à-vis validation
Authors: Guthikonda Nagaraju , Kameswari D P S L , Manikanta E , Shiva S Sai , Sree Harsha S , Ikkurthi V R , Prem Kiran P
Published: April 2023

A clear visualization of the physical processes of spatially confined ns laser induced atmospheric air plasma within a rectangular glass cavity using optical imaging is presented. The occurrence of various processes starting from the early plasma and shock wave expansion dynamics to shock reflection at the cavity boundaries and compression of the plasma due to reflected shockwaves is studied using defocused shadowgraphy and self-emission imaging techniques. Experimentally, we evidenced that the counter propagating reflected primary shockwaves interact with the expanding plasma generating a secondary shockwave which compresses the plasma core, modifying the plasma morphology resulting in enhanced plasma parameters. The numerical simulations performed via the two-dimensional hydrodynamic (2D-HD) FLASH codes, revealed that the number density increases up to a maximum of 3.6 times compared to the unconfined plasma. The input laser pulse energy and the aspect ratio of the cavity is observed to play a dominant role in the confinement and compression of the plasma.
Role of rare-earth metals (R) in the appearance of relaxation processes in AL–Ni–R metal melts
Authors: Beltyukov Anatoly L , Menshikova Svetlana G , Lad’yanov Vladimir I
Published: April 2023

The temperature and time dependences of the viscosity of liquid ternary alloys Al87Ni8Y5, Al86Ni8La6, Al86Ni8Ce6, Al86Ni6Co8, Al86Ni10Co4 and binary melts Al90(Y/Ni/Co)10 have been studied after different temperature-time treatment of the melt. It is shown that long-time relaxations in the Al–TM–R melts occur only after the phase transition ‘crystal-liquid’ due to the melt transition from the non-equilibrium to equilibrium state. The non-equilibrium state of the melt appears due to inheriting non-equilibrium atomic groups during melting; the atomic groups have ordering characteristic of chemical compounds of the Al
x
R
у
type present in solid-state alloys.
Ferromagnetic frozen structures from the dipolar hard spheres fluid at moderate and small volume fractions
Authors: Malherbe J-G , Russier V , Alonso Juan J
Published: April 2023

We study the magnetic phase diagram of an ensemble of dipolar hard spheres (DHSs) with or without uniaxial anisotropy and frozen in position on a disordered structure by tempered Monte Carlo simulations. The crucial point is to consider an anisotropic structure, obtained from the liquid state of the DHS fluid, frozen in its polarized state at low temperature. The freezing inverse temperature

β

f

determines the degree of anisotropy of the structure which is quantified through a structural nematic order parameter,

λ

s

. The case of the non zero uniaxial anisotropy is considered only in its infinitely strong strength limit where the system transforms in a dipolar Ising model (DIM). The important finding of this work is that both the DHS and the DIM with a frozen structure build in this way present a ferromagnetic phase at volume fractions below the threshold value where the corresponding isotropic DHS systems exhibit a spin glass phase at low temperature.
A novel data-driven method for fuel-consumption prediction based on fast converged kernel extreme learning machine
Authors: Lyu Zhichao , Wu Guangqiang , Wang Qiming
Published: April 2023

An accurate fuel consumption prediction is significant to fuel-economy-oriented optimization, which can improve vehicle fuel economy. Based on the data-driven prediction framework, this paper proposes a real-time fuel consumption prediction model (RFCPM) using kernel extreme learning machine (KELM) which is optimized by fast converged grey wolf algorithm (FCGWA). A new steering function of FCGWA and a new activation function for KELM are presented to ensure the fast converge speed and higher accuracy performance. First, the characteristic variables of RFCPM are selected by reference to the model-based fuel consumption prediction method. Second, a KELM is adopted to predict fuel consumption. Third, FCGWA is adopted to select the best parameters of KELM using k-fold cross-validation method. Finally, the best model is chosen through real-vehicle test. Test results are compared with the original ELM and the wildly used WNN. The experiment shows that the proposed method significantly outperforms the original ELM and WNN in terms of both prediction accuracy and training time.
Microvibration streaming measurements using dynamic compressed sensing for satellites
Authors: Li Li , Zhou Miaomiao , Zhu Ye , Tao Lixuan , Liang Xuwen
Published: April 2023

Long-term monitoring of satellite microvibrations generates a significant amount of data streams, placing strain on satellites with limited transmission capacity. To relieve this transmission strain, a dynamic compressed sensing (CS) framework is proposed for measuring satellite microvibrations. Microvibration streams are measured block by block and then reconstructed using a dynamic recovery algorithm. The recovery solution of one block can be used as a priori knowledge for the next block, allowing for faster updates. However, existing dynamic recovery algorithms are only applicable in the real domain and cannot be applied to microvibrations projected on a Fourier basis in the complex domain. In light of this event, the dynamic homotopy algorithm is expanded to the complex domain to deal with microvibration signals that are sparse in the Fourier basis. In comparison to conventional uniform sampling methods, the experimental results show that the dynamic CS with the expanded recovery algorithm can achieve a maximum root-mean-square acceleration (Grms) deviation of 4% in power spectrum density with one-fifth of the sampling points. Compared to recovery algorithms applicable to fixed measurements, the dynamic algorithm can achieve comparable accuracy in about one-third of the computation time. The experimental findings demonstrate the feasibility of satellite microvibrations measurements using dynamic CS.
In situ correction of recombination effects in ultra-high dose rate irradiations with protons
Authors: Schaefer R , Psoroulas S , Weber D C
Published: April 2023

Background. At the Center for Proton Therapy at the Paul Scherrer Institute (PSI) the delivery of proton radiation is controlled via gas-based ionization chambers: the beam is turned off when a certain amount of preset charge has been collected. At low dose rates the charge collection efficiency in these detectors is unity, at ultra-high dose rates it is less due to induced charge recombination effects. If not corrected, the latter would lead to an overdosage. Purpose. In the scope of this work, we developed a novel approach to an in situ charge recombination correction for our dose defining detectors, when irradiated with a proton beam at ultra-high dose rates. This approach is based on the Two-Voltage-Method. Methods. We have translated this method to two separate devices operated simultaneously at different conditions. By doing so, the charge collection losses can be corrected directly and without the need for empirical correction values. This approach has been tested at ultra-high dose rates; proton beam was delivered by the COMET cyclotron to Gantry 1 at PSI. Results. We were able to correct the charge losses caused by recombination effects at local beam currents of approximately 700 nA (i.e. instantaneous dose rate of 3600 Gy s–1 at isocenter). The corrected collected charges in our gaseous detectors were compared against recombination-free measurements with a Faraday cup. The ratio of both quantities shows no significant dose rate dependence within their respective combined uncertainties. Conclusions. Correcting recombination effects in our gas-based detectors with the novel method greatly eases the handling of Gantry 1 as ‘FLASH test bench’. Not only is the application of a preset dose more accurate compared to using an empirical correction curve, also the re-determination of empirical correction curves in the case of a beam phase space change can be omitted.
A deep learning approach for automatic delineation of clinical target volume in stereotactic partial breast irradiation (S-PBI)
Authors: Kazemimoghadam Mahdieh , Yang Zi , Chen Mingli , Rahimi Asal , Kim Nathan , Alluri Prasanna , Nwachukwu Chika , Lu Weiguo , Gu Xuejun
Published: April 2023

Accurate and efficient delineation of the clinical target volume (CTV) is of utmost significance in post-operative breast cancer radiotherapy. However, CTV delineation is challenging as the exact extent of microscopic disease encompassed by CTV is not visualizable in radiological images and remains uncertain. We proposed to mimic physicians’ contouring practice for CTV segmentation in stereotactic partial breast irradiation (S-PBI) where CTV is derived from tumor bed volume (TBV) via a margin expansion followed by correcting the extensions for anatomical barriers of tumor invasion (e.g. skin, chest wall). We proposed a deep-learning model, where CT images and the corresponding TBV masks formed a multi-channel input for a 3D U-Net based architecture. The design guided the model to encode the location-related image features and directed the network to focus on TBV to initiate CTV segmentation. Gradient weighted class activation map (Grad-CAM) visualizations of the model predictions revealed that the extension rules and geometric/anatomical boundaries were learnt during model training to assist the network to limit the expansion to a certain distance from the chest wall and the skin. We retrospectively collected 175 prone CT images from 35 post-operative breast cancer patients who received 5-fraction partial breast irradiation regimen on GammaPod. The 35 patients were randomly split into training (25), validation (5) and test (5) sets. Our model achieved mean (standard deviation) of 0.94 (±0.02), 2.46 (±0.5) mm, and 0.53 (±0.14) mm for Dice similarity coefficient, 95th percentile Hausdorff distance, and average symmetric surface distance respectively on the test set. The results are promising for improving the efficiency and accuracy of CTV delineation during on-line treatment planning procedure.
Device-independent oblivious transfer from the bounded-quantum-storage-model and computational assumptions
Authors: Broadbent Anne , Yuen Peter
Published: April 2023

We present a device-independent protocol for oblivious transfer (DIOT) and analyse its security under the assumption that the receiver’s quantum storage is bounded during protocol execution and that the device behaves independently and identically in each round. We additionally require that, for each device component, the input corresponding to the choice of measurement basis, and the resulting output, is communicated only with the party holding that component. Our protocol is everlastingly secure and, compared to previous DIOT protocols, it is less strict about the non-communication assumptions that are typical from protocols that use Bell inequality violations; instead, the device-independence comes from a protocol for self-testing of a single (quantum) device which makes use of a post-quantum computational assumption.
Clarifying some common misconceptions about gravitational effects in free falling frames
Authors: Re Fiorentin Stefano
Published: April 2023

It is often stated that in free falling systems, locally, the effects of gravity can be ‘transformed away’. This statement is part of many, even authoritative, versions of the so-called ‘Strong Equivalence Principle’. Gravitational effects, however, cannot be completely ‘transformed away’ in free falling systems. In fact, it is well known and generally remarked in the literature that there are (usually tiny) gravitational effects related to the second derivatives of the components of the metric tensor that are not eliminated even in free falling systems. But the misconception is worsened by the fact that there are other fundamental gravitational effects that also occur in free falling systems, which we focus on in this paper. Firstly, the gravitational slowing of time: a fact fundamental to the operation of the Global Positioning System, the occurrence of which in free falling systems subject to gravitational acceleration is generally explained by invoking the axiom that acceleration does not affect the flow of time (the so-called ‘clock hypothesis’). Secondly, there is a gravitational effect on space, dual to that on time and consisting of its stretching (as has been shown elsewhere), which is equally present in free falling frames. We will show here that it is possible to deduce the presence of these gravitational effects on time and space in free falling systems as well, directly from the metric, thus clarifying that neither the small gravitational effects related to the curvature of spacetime nor the fundamental gravitational effects on time and space can be eliminated in free falling systems. In the latter, only gravitational acceleration is actually ‘transformed away’, making them particular inertial frames; the Equivalence Principle (without the designation ‘Strong’ anymore) should be limited to stating this.
Comprehensive experimental study of NBνN barrier structures based on n-HgCdTe MBE for detection in MWIR and LWIR spectra
Authors: Voitsekhovskii Alexander V , Dzyadukh Stanislav M , Gorn Dmitry I , Dvoretsky Sergey A , Mikhailov Nikolay N , Sidorov Georgiy Yu , Yakushev Maxim V
Published: April 2023

This work is devoted to a comprehensive experimental study of the electrical and photoelectric characteristics of barrier photosensitive structures in the NBνN configuration based on n-HgCdTe (MCT). Seven different types of photosensitive structures for middle wavelength (MWIR) and long wavelength (LWIR) infrared (IR) radiation ranges grown by molecular beam epitaxy (MBE) have been studied by complex conductivity spectroscopy method. The current-voltage characteristics (CVC) were measured both in the dark and in the presence of illumination. Based on the measured dependences of the dark current density on temperature and the ratio of the perimeter to the area of the structure, the dominant contribution of the bulk current component compared to the surface component for the MWIR structure (x ∼ 0.30) was established. This fact was confirmed by the value of the activation energy (from the Arrhenius plots) corresponding to the band gap. The results of frequency measurements of the differential conductivity of MIS structures based on NBνN also give a close activation energy, which corresponds to the diffusion limitation. LWIR structures (x ∼ 0.20) are characterized by an increase in the contribution of the surface leakage current in the total dark current. In this case, the activation energy determined from MIS measurements exceeds the band gap of the ν-layer, which is associated with the presence of an energy barrier for holes in the valence band. It is shown that if the problem of passivation of mesa structures is solved, it is possible to fabricate efficient MWIR and LWIR nBn, NBνN detectors based on MBE HgCdTe with high threshold parameters.
Cosmic decoherence: primordial power spectra and non-Gaussianities
Authors: Daddi Hammou Aoumeur , Bartolo Nicola
Published: April 2023

We study the effect of quantum decoherence on the inflationary cosmological perturbations.
This process might imprint specific observational signatures revealing the quantum nature of the
inflationary mechanism being related to the longstanding issue of the quantum-to-classical
transition of inflationary fluctuations. Several works have investigated the effect of quantum
decoherence on the statistical properties of primordial fluctuations. In particular, it has been
shown that cosmic decoherence leads to corrections to the curvature power spectrum predicted by
standard slow-roll inflation. Equally interesting, a non zero curvature trispectrum has been
shown to be purely induced by cosmic decoherence but, surprisingly, decoherence seems not to
generate any bispectrum. We further develop such an analysis by adopting a generalized form of the
pointer observable, showing that decoherence does induce a non vanishing curvature bispectrum and
providing a specific underlying concrete physical process. Present constraints on primordial
bispectra allow to put an upper bound on the strength of the environment-system interaction. In
full generality, the decoherence-induced bispectrum can be scale dependent provided one imposes
the corresponding correction to the power spectrum to be scale independent. Such scale dependence
on the largest cosmological scales might represent a distinctive imprint of the quantum
decoherence process taking place during inflation. We also provide a criterion that allows to
understand when cosmic decoherence induces scale independent corrections, independently of the
type of environment considered. As a final result, we study the effect of cosmic decoherence on
tensor perturbations and we derive the decoherence corrected tensor-to-scalar perturbation
ratio. In specific cases, decoherence induces a blue tilted correction to the standard tensor
power spectrum.
Adolescent Growth Spurt and Type 2 Diabetes Risk in Southwestern American Indians
Authors: Ramirez-Luzuriaga Maria J , Kobes Sayuko , Sinha Madhumita , Knowler William C , Hanson Robert L
Published: April 2023

Early puberty onset is associated with higher risk of diabetes, but most studies have not accounted for childhood factors that may confound the association. Using data from a study conducted in an Indigenous community in Arizona (1965–2007), we examined associations of timing and velocity of the adolescent growth spurt with type 2 diabetes, and whether these associations are mediated by childhood body mass index and insulinemia. Adolescent growth parameters were derived from the Preece-Baines growth model, a parametric growth curve fitted to longitudinal height data, for 861 participants with height measurements spanning the whole period of growth. In males, older age at take-off, age at peak velocity, and age at maturation were associated with decreased prevalence of diabetes (odds ratio (OR) = 0.43 per year, 95% confidence interval (CI): 0.27, 0.69; OR = 0.50, 95% CI: 0.35, 0.72; OR = 0.58, 95% CI: 0.41, 0.83, respectively), while higher velocity at take-off was associated with increased risk (OR = 3.47 per cm/year, 95% CI: 1.87, 6.42) adjusting for age, birth year, and maternal diabetes. Similar results were observed with incident diabetes. Our findings suggest that an early and accelerated adolescent growth spurt is a risk factor for diabetes, at least in males. These associations are only partially explained by measures of adiposity and insulinemia.
MetChem: a new pipeline to explore structural similarity across metabolite modules
Authors: Abdel-Shafy Ebtesam A , Melak Tadele , MacIntyre David A , Zadra Giorgia , Zerbini Luiz F , Piazza Silvano , Cacciatore Stefano
Published: April 2023

Computational analysis and interpretation of metabolomic profiling data remains a major challenge in translational research. Exploring metabolic biomarkers and dysregulated metabolic pathways associated with a patient phenotype could offer new opportunities for targeted therapeutic intervention. Metabolite clustering based on structural similarity has the potential to uncover common underpinnings of biological processes. To address this need, we have developed the MetChem package. MetChem is a quick and simple tool that allows to classify metabolites in structurally related modules, thus revealing their functional information.

Availabilityand implementation

MetChem is freely available from the R archive CRAN (http://cran.r-project.org). The software is distributed under the GNU General Public License (version 3 or later).
DFHiC: a dilated full convolution model to enhance the resolution of Hi-C data
Authors: Wang Bin , Liu Kun , Li Yaohang , Wang Jianxin
Published: April 2023

Motivation

Hi-C technology has been the most widely used chromosome conformation capture (3C) experiment that measures the frequency of all paired interactions in the entire genome, which is a powerful tool for studying the 3D structure of the genome. The fineness of the constructed genome structure depends on the resolution of Hi-C data. However, due to the fact that high-resolution Hi-C data require deep sequencing and thus high experimental cost, most available Hi-C data are in low-resolution. Hence, it is essential to enhance the quality of Hi-C data by developing the effective computational methods.

Results

In this work, we propose a novel method, so-called DFHiC, which generates the high-resolution Hi-C matrix from the low-resolution Hi-C matrix in the framework of the dilated convolutional neural network. The dilated convolution is able to effectively explore the global patterns in the overall Hi-C matrix by taking advantage of the information of the Hi-C matrix in a way of the longer genomic distance. Consequently, DFHiC can improve the resolution of the Hi-C matrix reliably and accurately. More importantly, the super-resolution Hi-C data enhanced by DFHiC is more in line with the real high-resolution Hi-C data than those done by the other existing methods, in terms of both chromatin significant interactions and identifying topologically associating domains.

Availability and implementation

https://github.com/BinWangCSU/DFHiC.
The Effects of Decent Work and Social Support on Enhancing Collective Psychological Ownership Amongst Young Adult Social Workers
Authors: Su Xuebing , Wong Victor
Published: April 2023

It has been a pronounced concern for social service organisations (SSOs) on how to foster a sense of co-ownership amongst their employees. A total of 937 valid questionnaires were collected amongst social worker participants aged twenty-one to twenty-nine years working in three different places of China, namely, Hong Kong, Shenzhen and Guangzhou. By confirming the hypotheses, the findings revealed that decent work and social support were positively associated with the collective psychological ownership (CPO) held by young adult social workers, and decent work enhanced CPO shared by them through an indirect mechanism of enhancing their social support at work. This is the first-ever study providing empirical evidence to support the association of decent work and social support with CPO amongst young adult employees in organisational context. The findings of this study can help inform the development of human resources management strategies for cultivating CPO, justify and expand the promotion of decent work in conjunction with the framework of psychology of working theory and interpersonal perspective, and inspire relevant research and practice with regard to the personal development of young adult social workers and the sustainable development of SSOs.
Disrupted resting-sate brain network dynamics in children born extremely preterm
Authors: Padilla Nelly , Escrichs Anira , del Agua Elvira , Kringelbach Morten , Donaire Antonio , Deco Gustavo , Åden Ulrika
Published: April 2023

The developing brain has to adapt to environmental and intrinsic insults after extremely preterm (EPT) birth. Ongoing maturational processes maximize their fit to the environment and this can provide a substrate for neurodevelopmental failures. Resting-state functional magnetic resonance imaging was used to scan 33 children born EPT, at < 27 weeks of gestational age, and 26 full-term controls at 10 years of age. We studied the capability of a brain area to propagate neural information (intrinsic ignition) and its variability across time (node-metastability). This framework was computed for the dorsal attention network (DAN), frontoparietal, default-mode network (DMN), and the salience, limbic, visual, and somatosensory networks. The EPT group showed reduced intrinsic ignition in the DMN and DAN, compared with the controls, and reduced node-metastability in the DMN, DAN, and salience networks. Intrinsic ignition and node-metastability values correlated with cognitive performance at 12 years of age in both groups, but only survived in the term group after adjustment. Preterm birth disturbed the signatures of functional brain organization at rest in 3 core high-order networks: DMN, salience, and DAN. Identifying vulnerable resting-state networks after EPT birth may lead to interventions that aim to rebalance brain function.
Processing negative emotion in two languages of bilinguals: Accommodation and assimilation of the neural pathways based on a meta-analysis
Authors: Dang Qinpu , Ma Fengyang , Yuan Qiming , Fu Yongben , Chen Keyue , Zhang Zhaoqi , Lu Chunming , Guo Taomei
Published: April 2023

Numerous functional magnetic resonance imaging (fMRI) studies have examined the neural mechanisms of negative emotional words, but scarce evidence is available for the interactions among related brain regions from the functional brain connectivity perspective. Moreover, few studies have addressed the neural networks for negative word processing in bilinguals. To fill this gap, the current study examined the brain networks for processing negative words in the first language (L1) and the second language (L2) with Chinese-English bilinguals. To identify objective indicators associated with negative word processing, we first conducted a coordinate-based meta-analysis on contrasts between negative and neutral words (including 32 contrasts from 1589 participants) using the activation likelihood estimation method. Results showed that the left medial prefrontal cortex (mPFC), the left inferior frontal gyrus (IFG), the left posterior cingulate cortex (PCC), the left amygdala, the left inferior temporal gyrus (ITG), and the left thalamus were involved in processing negative words. Next, these six clusters were used as regions of interest in effective connectivity analyses using extended unified structural equation modeling to pinpoint the brain networks for bilingual negative word processing. Brain network results revealed two pathways for negative word processing in L1: a dorsal pathway consisting of the left IFG, the left mPFC, and the left PCC, and a ventral pathway involving the left amygdala, the left ITG, and the left thalamus. We further investigated the similarity and difference between brain networks for negative word processing in L1 and L2. The findings revealed similarities in the dorsal pathway, as well as differences primarily in the ventral pathway, indicating both neural assimilation and accommodation across processing negative emotion in two languages of bilinguals.
Accurate corresponding fiber tract segmentation via FiberGeoMap learner with application to autism
Authors: Wang Zhenwei , He Mengshen , Lv Yifan , Ge Enjie , Zhang Shu , Qiang Ning , Liu Tianming , Zhang Fan , Li Xiang , Ge Bao
Published: April 2023

Fiber tract segmentation is a prerequisite for tract-based statistical analysis. Brain fiber streamlines obtained by diffusion magnetic resonance imaging and tractography technology are usually difficult to be leveraged directly, thus need to be segmented into fiber tracts. Previous research mainly consists of two steps: defining and computing the similarity features of fiber streamlines, then adopting machine learning algorithms for fiber clustering or classification. Defining the similarity feature is the basic premise and determines its potential reliability and application. In this study, we adopt geometric features for fiber tract segmentation and develop a novel descriptor (FiberGeoMap) for the corresponding representation, which can effectively depict fiber streamlines’ shapes and positions. FiberGeoMap can differentiate fiber tracts within the same subject, meanwhile preserving the shape and position consistency across subjects, thus can identify common fiber tracts across brains. We also proposed a Transformer-based encoder network called FiberGeoMap Learner, to perform segmentation based on the geometric features. Experimental results showed that the proposed method can differentiate the 103 various fiber tracts, which outperformed the existing methods in both the number of categories and segmentation accuracy. Furthermore, the proposed method identified some fiber tracts that were statistically different on fractional anisotropy (FA), mean diffusion (MD), and fiber number ration in autism.
Simultaneous Determination of Ceftazidime in Three Different Pharmaceutical Preparations Combined with Either Tazobactam, Tobramycin or Sulbactam by HPTLC-Spectrodensitometric Method
Authors: Salem Hesham , Omar Mahmoud A , Mazen Dina Z , Nour El-Deen Deena A M
Published: April 2023

A new, simple hight performance thin layer chromatography (HPTLC)-Spectrodensitometric strategy was created and approved for the synchronous estimation of four antibacterial specialists: ceftazidime (CEF), tazobactam (TAZ), tobramycin (TOB) and sulbactam (SUL). The four compounds were separated on TLC aluminum plates covered with silica gel 60 F254, using chloroform–acetonitrile–methanol–ammonia (4:1:0.5:0.15, v/v/v/v) as a mobile phase at 254 nm. Linear correlation was obeyed over the concentration ranges of 12.0–72.0, 2.0–12.0, 3.0–18.0 and 10.0–50.0 μg mL−1 for CEF, TAZ, TOB and SUL, respectively. The proposed approach is efficient, repeatable and convenient as a flexible method for the quality control of diverse combinations of these pharmaceuticals in various pharmaceutical preparations, with high percent recoveries that are highly consistent with labeled data. When the findings of the proposed technique were compared to those of the comparison methods, there were no critical contrasts in terms of precision and accuracy.
How much does the presentation pattern of atrial fibrillation affect thrombo-embolic risk and mortality?
Authors: Turturiello Dario , Cappato Riccardo
Published: April 2023

Atrial fibrillation (AF) is associated with a substantial increase in mortality and morbidity. Systemic thrombo-embolism is the most serious complication associated with this arrhythmia. The use of anticoagulant drugs is the cornerstone of therapy for the prophylaxis of stroke and peripheral ischaemia in these patients. The current guidelines recommend the use of anticoagulant drugs based on the thrombo-embolic risk profile of each individual patient calculated by SCORE based on the presence or absence of clinical risk factors and regardless of the presentation pattern of AF. A review of literature data investigating the effect of AF presentation pattern on thrombo-embolic risk and mortality showed an increased risk of both thrombo-embolic events and death in patients with non-paroxysmal AF compared to patients with paroxysmal AF. Most of these studies, however, consist of post-hoc analyses of large trials or observational studies and meta-analyses derived from these, resulting in an important limitation in the interpretation of data derived from such studies. At the same time, these data suggest the need for both new therapies to prevent AF progression and for further studies to explore the integration of AF presentation pattern into models of thrombo-embolic risk.
What is the role of coronary revascularization to recover the contractility of the dysfunctional heart?
Authors: Vassiliki’ Cousoumbas Gloria , Casella Gianni , Di Pasquale Giuseppe
Published: April 2023

Coronary artery disease is the predominant aetiology of heart failure and left ventricular dysfunction in industrialized countries. The pathophysiological substrate of hibernating myocardium constitutes the conceptual target of coronary revascularization by coronary artery bypass graft (CABG) or coronary angioplasty or percutaneous coronary intervention (PCI). Studies, mainly observational, conducted in the past have demonstrated a prognostic benefit of CABG on survival. These findings were confirmed by the long-term follow-up of the STICH study in which, however, documentation of inducible ischaemia or myocardial viability was not predictive of a prognostic benefit of CABG. Revascularization via PCI in the recent REVIVED-BCIS2 study did not demonstrate a significant benefit in terms of death or heart failure hospitalization compared with optimal medical therapy. Pending the long-term follow-up of the REVIVED-BCIS2 study, optimized medical therapy, cardiac resynchronization therapy, and the implantable cardioverter defibrillator, where indicated, are the mainstay of treatment in patients with dilated ischaemic cardiomyopathy. The decision for coronary revascularization is made in the individual patient, possibly with a higher bias in patients with angina, three-vessel coronary artery disease, severe left ventricular dysfunction, and cardiac remodelling.
In search of new gatekeepers: coronary CT (Computed Tomography) in acute coronary syndrome
Authors: Schillaci Matteo , Marchetti Davide , Andreini Daniele
Published: April 2023

Coronary computed tomography (CCT) is a non-invasive imaging method that allows visualization of the epicardial coronary arteries. The diagnostic and prognostic role of CCT has been demonstrated by various randomized trials to such an extent that it has been included as a Class I, level of evidence B recommendation in the latest European Society of Cardiology (ESC) guidelines for the diagnosis of chronic coronary syndrome in patients at intermediate-low cardiovascular risk. In addition to the anatomical evaluation, the CCT allows to evaluate the presence of high-risk characteristics of the atherosclerotic plaque (napkin-ring sign, positive remodelling, spotty calcification, and low-attenuation plaque), thus discriminating the stability of the atheromatous pathology. Furthermore, among the potential of cardiac CT in the emergency department, the possibility of making a triple rule-out must be underlined, excluding three potential big killers as the cause of acute chest pain: acute coronary syndrome, pulmonary embolism, and aortic dissection. Various randomized clinical studies have demonstrated that the prognosis of the patient with chronic coronary artery disease (CAD) improves only if a haemodynamically significant stenosis is treated, generally investigated with invasive fractional flow reserve (FFR); CCT technological advances have made it possible to create an algorithm for calculating the FFR-CT, an index of haemodynamic significance of coronary stenosis, whose correlation with the invasive FFR data and, consequently, with the prognosis has been demonstrated of patients with CAD.
How much does hypertension in pregnancy affect the risk of future cardiovascular events?
Authors: Mureddu Gian Francesco
Published: April 2023

Hypertensive disorders in pregnancy (HDP) include essential (or secondary) hypertension occurring before 20 weeks of gestation or in women already on antihypertensive therapy prior to pregnancy, gestational hypertension, developing after 20 weeks of gestation without significant proteinuria, and pre-eclampsia or AH onset after 20 weeks of pregnancy in the presence of proteinuria. The development of HDP is associated with a higher incidence of long-term cardiovascular (CV) adverse events, such as myocardial infarction, heart failure, stroke, and CV death. Women who develop high blood pressure in their first pregnancy have an increased risk of complication in a subsequent pregnancy. In the years following delivery, pregnant women with hypertensive disorders develop subclinical atherosclerosis and alterations of cardiac structure and function that may lead to CV disease and heart failure. Thus, it is recommended to monitor these changes over time and subject in pregnant women with these characteristics to CV surveillance through structured and multidisciplinary interventions for CV prevention.
Ablation of ventricular arrhythmias in cardiogenetic diseases
Authors: Pappone Carlo , Boccellino Antonio , Ciconte Giuseppe
Published: April 2023

Sudden cardiac death is a leading cause of mortality, claiming millions of lives every year. Recent advances in cardiac arrhythmia mapping have demonstrated that the ventricular epicardial region has a critical arrhythmogenic role in some inherited cardiogenetic diseases. Historically, electroanatomic abnormalities have been identified in the ventricular epicardium of patients with arrhythmogenic right ventricular cardiomyopathy. More recently, epicardial pathological substrates have been identified also in electrical disease (Brugada syndrome, early repolarization syndrome) and currently in long QT syndrome. In light of these findings, the epicardial area has emerged as an important determinant in sudden cardiac death-related cardiomyopathies.
Therapy of Type 2 diabetes: more gliflozines and less metformin?
Authors: Verdecchia Paolo , Murdolo Giuseppe , Coiro Stefano , Santucci Andrea , Notaristefano Francesco , Angeli Fabio , Cavallini Claudio
Published: April 2023

Metformin is a frequently used anti-diabetic drug. In addition to the well-known modulating properties on glyco-metabolic control, metformin reduces cardiovascular (CV) risk partly independently of its anti-hyperglycaemic effect. The use of ‘new’ anti-diabetic drugs, inhibitors of the renal Na-glucose co-transporter (SGLTs-I or ‘gliflozines’) and GLP-1 receptor agonists (GLP1-RAs), has further contributed to challenge the strictly ‘gluco-centric’ view of diabetic CV disease. Several controlled trials have demonstrated that the cardio-renal benefits of gliflozines and GLP1-RAs are present regardless of the presence of metformin as ‘background’ therapy. The impact on the ‘cardio-renal continuum’ exerted by SGLTs-I was also noted in non-diabetic patients with heart failure and reduced or preserved ventricular function and different levels of renal function. These drugs reduced re-hospitalization, CV mortality, and progression to end-stage renal disease. These clinical acquisitions, implemented by Scientific Societies, have led to a change in the therapeutic approach to diabetic cardio-renal disease. Although metformin still represents a valid therapeutic option to be offered particularly to ‘naïve’ diabetic patients without previous cardio-renal events, SGLTs-I and/or GLP1-RAs emerge as ‘first-line’ drugs in diabetic patients with previous CV events, or at high CV risk, without having to request ‘on board’ metformin therapy.
Relationship between epicardial adipose tissue measured by computed tomography and premature ventricular complexes originating from different sites
Authors: Shen Junxian , Zhu Didi , Chen Long , Cang Jiehui , Zhao Zhen , Ji Yuqin , Liu Shangshang , Miao Hongyu , Liu Yaowu , Zhou Qianxing , He Yanru , Cai Junyan
Published: April 2023

Aims

This study aims to explore the association between the features of epicardial adipose tissue (EAT) in different zones and premature ventricular complexes (PVCs) originating from different sites by computed tomography (CT).

Methods and results

A total of 136 patients who underwent radiofrequency ablation for PVCs were incorporated in this study. One hundred and thirty-six matched controls were included in this study using the case-control method (1:1 matching). PVCs were classified into four subgroups: (1) right ventricular outflow tract (RVOT-PVCs), (2) non-RVOT of the right ventricle (RV-PVCs), (3) left ventricular outflow tract (LVOT-PVCs), and (4) non-LVOT of the left ventricle (LV-PVCs). The volume and density of EAT were quantified by CT. Patients with PVCs had a significantly higher volume and lower density of EAT than the controls (P < 0.001). The LVOT-PVCs and LV-PVCs had a higher left ventricle periventricular EAT volume (LV-EATv) proportion (P < 0.05). The right ventricle periventricular EAT volume (RV-EATv) proportion was higher in ROVT-PVCs and LVOT-PVCs (P < 0.05). RVOT-PVC patients had a higher volume ratio and a smaller density differential (P < 0.05). Patients with LVOT-PVCs had a lower volume ratio and the LV-PVCs showed a greater density differential (P < 0.05).

Conclusion

Higher volume and lower density of EAT were significantly associated with frequent PVCs. The RVOT-PVC patients had a higher volume ratio and a smaller density differential. The LVOT-PVCs had a lower volume ratio and the LV-PVCs showed a greater density differential. These suggest a link between EAT structural properties and PVCs and a potential role for regional EAT in the development of PVCs.
More is less: inducing sparsity via overparameterization
Authors: Chou Hung-Hsu , Maly Johannes , Rauhut Holger
Published: April 2023

In deep learning, it is common to overparameterize neural networks, that is, to use more parameters than training samples. Quite surprisingly training the neural network via (stochastic) gradient descent leads to models that generalize very well, while classical statistics would suggest overfitting. In order to gain understanding of this implicit bias phenomenon, we study the special case of sparse recovery (compressed sensing) which is of interest on its own. More precisely, in order to reconstruct a vector from underdetermined linear measurements, we introduce a corresponding overparameterized square loss functional, where the vector to be reconstructed is deeply factorized into several vectors. We show that, if there exists an exact solution, vanilla gradient flow for the overparameterized loss functional converges to a good approximation of the solution of minimal $\ell _1$-norm. The latter is well-known to promote sparse solutions. As a by-product, our results significantly improve the sample complexity for compressed sensing via gradient flow/descent on overparameterized models derived in previous works. The theory accurately predicts the recovery rate in numerical experiments. Our proof relies on analyzing a certain Bregman divergence of the flow. This bypasses the obstacles caused by non-convexity and should be of independent interest.
A systematic literature review of milk consumption and associated bacterial zoonoses in East Africa
Authors: Mpatswenumugabo Jean Pierre , Mukasafari Marie Anne , Ndahetuye Jean Baptiste , Wredle Ewa , Båge Renée
Published: April 2023

Consumption of unsafe animal-source foods is the major cause of foodborne disease outbreaks in low-income countries. Despite current knowledge of the threat posed by raw milk consumption to human health, people in many countries in East Africa still consume unboiled milk. This literature review explored the association between milk consumption and the occurrence of five milk-borne bacterial zoonoses: brucellosis, salmonellosis, campylobacteriosis, Escherichia coli infections, and tuberculosis. A search for literature published up to 1 October 2021 was conducted through the Web of Science, PubMed, and Scopus databases, using Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines. The selection process yielded 65 articles describing studies conducted in East Africa 2010–2021, which were carefully scrutinized. The most investigated pathogen was Brucella spp. (54.5%), followed by E. coli (18.2%), Salmonella spp. (12.1%), Mycobacterium spp. (6.1%), and E. coli O157: H7 (6.1%). The most common predisposing factors for potential milk-borne disease outbreaks were consumption of contaminated raw milk, inadequate cold storage along the milk value chain, poor milk handling practices, and lack of awareness of the health risks of consuming unpasteurized milk. Thus, a tailor-made training program is needed for all milk value chain actors to enhance the safety of milk sold in informal markets, and a One Health approach should be applied. Future studies should employ more advanced diagnostic techniques and countries in East Africa should invest in modern diagnostic tools and equipment, both in hospitals and in local rural settings where most cases occur.
Enhancing toxic sugar meals against Aedes aegypti (Diptera: Culicidae) by adulterating with erythritol in combination with other active ingredients
Authors: Baker Kobi A , White Gregory S , Faraji Ary , Bibbs Christopher S
Published: April 2023

Attractive toxic sugar baits (ATSBs) are an underexploited method for mosquito control. For ATSBs to be more widely accepted, demonstrably effective ingredients need to be verified. We investigated erythritol as a toxic additive in sugar meals against Aedes aegypti (L.) for potential future use in ATSBs. Erythritol is a sugar alcohol that is commonly used as a sugar substitute, while also being toxic to mosquitoes. Our studies tested formulations of erythritol, sucrose, and blends of both. Secondary investigations included combinations with the active ingredients Bacillus thuringiensis israelensis, spinosyn, and boric acid. Adult Ae. aegypti were separated into test groups and provided various combinations. Formulations containing erythritol, with or without another toxicant, exhibited 90% mortality within 72 h of observation (P = 0.03192). Additionally, erythritol appeared more effective when combined with sucrose in a 1:1 ratio (5% concentration each). This combination showed a 24% and 85% increase in mortality when combined with boric acid and Bti, respectively, at 48 h compared with equivalent groups containing only 10% sucrose. Erythritol appears to kill adult mosquitoes, even in relatively low concentrations, without another toxicant being required. However, erythritol also effectively enhances kill of main ingredient toxicants such as boric acid and Bti, showing a supporting role. The low concentration of erythritol needed to provide significant kill, its ability to fill in as both a sugar base and toxicant, and its ability to be safely handled by humans makes erythritol a strong candidate for use as a supporting ingredient in future bait formulations.
Thermomorphogenesis: opportunities and challenges in post-transcriptional regulation
Authors: Reis Rodrigo S
Published: April 2023

Plants exposed to mildly elevated temperatures display morphological and developmental changes collectively termed thermomorphogenesis. This adaptative process has several undesirable consequences for food production, including yield reduction and increased vulnerability to pathogens. Understanding thermomorphogenesis is, thus, critical for understanding how plants will respond to conditions of increasingly warmer temperature, such as those caused by climate change. Recently, major advances in that direction have been made, and it has become apparent that plants resort to a broad range of molecules and molecular mechanisms to perceive and respond to increases in environmental temperature. However, most effort has been focused on regulation of transcription and protein abundance and activity, with an important gap encompassing nearly all processes involving RNA (i.e. post-transcriptional regulation). Here, current knowledge of thermomorphogenesis involving transcriptional, post-transcriptional, and post-translational regulation is summarized, focusing on opportunities and challenges in understanding post-transcriptional regulation—a fertile field for exciting new discoveries.