External Sources Research Articles

Advancing non-invasive fetal health monitoring: A time–frequency approach to extracting fetal electrocardiogram signals

The fetal electrocardiogram (FECG) provides an important way for clinicians to assess fetal health and to monitor pregnancy conditions. Although FECG can be captured through abdominal electrocardiogram (AECG) recordings from pregnant women, it often receives interference from maternal cardiac activity and other external sources. Particularly, as the high-amplitude maternal electrocardiogram (MECG) typically obscures the waveform of the FECG, isolating FECG from the AECG signals is challenging. Nevertheless, the differences in frequency patterns between MECG and FECG suggest a potential way for reconstructing FECG by combining the frequency and amplitude information. To this end, we proposed a novel method for separating FECG signals from the AECG via the time–frequency representation. We designed an encoder–decoder architecture based hierarchical multiscale-aware network to capture features embedded in both the time and frequency domains. Equipped with a holistic attention-aware module (HAA), the model extracts and consolidates fetal heart activity-related features in the time–frequency domain. Further introducingan attention gate module (AG) to emphasize key features during encoder-to-decoder transmission, the model enhances the quality and efficiency of FECG extraction without any redundancy in high-quality feature mapping. The model was trained using a hybrid time-domain and frequency-domain loss function and validated on two public databases. Excellent performances, such as an average Pearson correlation coefficient of 0.85 for estimating the quality of FECG signals, were observed demonstrating its excellent performance and providing a promising non-invasive method for monitoring fetal health. These findings indicate that the proposed method effectively captures the amplitude differences between fetal and maternal heartbeats across various frequency components within the AECG, leading to the extraction of high-quality FECG signals.

PDB NextGen Archive: centralizing access to integrated annotations and enriched structural information by the Worldwide Protein Data Bank.

The Protein Data Bank (PDB) is the global repository for public-domain experimentally determined 3D biomolecular structural information. The archival nature of the PDB presents certain challenges pertaining to updating or adding associated annotations from trusted external biodata resources. While each Worldwide PDB (wwPDB) partner has made best efforts to provide up-to-date external annotations, accessing and integrating information from disparate wwPDB data centers can be an involved process. To address this issue, the wwPDB has established the PDB Next Generation (or NextGen) Archive, developed to centralize and streamline access to enriched structural annotations from wwPDB partners and trusted external sources. At present, the NextGen Archive provides mappings between experimentally determined 3D structures of proteins and UniProt amino acid sequences, domain annotations from Pfam, SCOP2 and CATH databases and intra-molecular connectivity information. Since launch, the PDB NextGen Archive has seen substantial user engagement with over 3.5 million data file downloads, ensuring researchers have access to accurate, up-to-date and easily accessible structural annotations. Database URL: http://www.wwpdb.org/ftp/pdb-nextgen-archive-site.

Oxygen-enriching triphase platform for reliable sensing of femtomolar Alzheimer’s neurofilament lights

Accurate quantification of neurofilament lights (NfLs), a prognostic blood biomarker, is highly required to predict neurodegeneration in the presymptomatic stages of Alzheimer’s disease. Here, we report self-oxygen-enriching coral structures with triphase interfaces for the label-free photocathodic detection of NfLs in blood plasma with femtomolar sensitivities and high reliability. In conventional photocathodic immunoassays, the poor solubility and sluggish diffusion rate of the dissolved oxygen serving as electron acceptors have necessitated the incorporation of additional electron acceptors or aeration procedures. To address the challenge, we designed the coral-like copper bismuth oxides (CBO) with robust solid–liquid–air contact boundaries that enrich the interfacial oxygen levels without an external aeration source. By optimally assembling the perfluorododecyltrichlorosilane (FTCS) and platinum (Pt) co-catalysts into the silver-doped CBO (Ag:CBO), the stable solid–liquid–air contact boundaries were formed within the sensor interfaces, which allowed for the abundant supply of air phase oxygen through an air pocket connected to the atmosphere. The Pt/FTCS-Ag:CBO exhibited the stable background signals independent of the dissolved oxygen fluctuations and amplified photocurrent signals by 1.76-fold, which were attributed to the elevated interfacial oxygen levels and 11.15 times-lowered mass transport resistance. Under the illumination of white light-emitting diode, the oxygen-enriching photocathodic sensor composed of Pt/FTCS-Ag:CBO conjugated with NfLs-specific antibodies precisely quantified the NfLs in plasma with a low coefficient of variation (≤2.97%), a high degree of recovery (>97.0%), and a limit of detection of 40.38 fg/mL, which was 140 times lower than the typical photocathodic sensor with diphase interfaces.

Effects of food waste hydrolysate as an external carbon source on defoaming in wastewater treatment with activated sludge process

The activated sludge process is the most widely used technology for treating municipal wastewater. However, thick foam often occurs in activated sludge process. Here, we reported for the first time the effect of food waste hydrolysate (FWH) as an external carbon source on defoaming in activated sludge process. The study found that FWH was effective in defoaming at a wide dose range of 50–1600 mg/L total solids, as exhibiting that the foaming tendency of FWH-added foam mixed liquor was reduced to 0 mL-foam/mL-air·min from initial 0.171 mL-foam/mL-air·min in the control without adding FWH with 100 % of defoaming efficiency. Fatty acids, oils, and solid particles in FWH jointly contributed to the deformation. Among these factors, the concentration of long-chain unsaturated fatty acids was mainly responsible for the defoaming. This work provides a cost-effective strategy to solve the foaming problem in activated sludge process as well as providing external carbon sources.

Improving the detection limit in lung counting with a segmented HPGe detector

A segmented High-Purity Germanium (HPGe) detector with a thin front segment together with various active and passive shield configurations was simulated with the aim of reducing the level of background events in lung counting applications. Eight different detector models were tested in a Geant4 simulation environment in a scenario where inhaled 241Am activity was deposited in the lungs of an ICRP adult reference computational phantom. In lung counting measurements, the Compton continuum in the spectrum is generated by the natural and man-made radionuclides inside the human body and the natural background radiation from the environment. The reduction in Minimum Detectable Activity (MDA) using the segmented HPGe detector combined with an active shield compared to a model with a single germanium crystal was investigated. A reduction in MDA up to 30% and 66% was obtained for internal and external sources, respectively. The results show that the detection limit and/or the measurement time in lung counting can be reduced using such a detector configuration. Furthermore, combining the segmented HPGe detector with an active shield would be particularly useful in field measurements.

First-principles screening of XSbF3 (X = Ba and Ra) fluoroperovskites: an insight into structural, optoelectronic and thermal properties

This work presents a computational study of the physical properties such as structural, electronic, optical and thermal properties of XSbF3 (X = Ba and Ra) fluoroperovskites. The calculations were performed using the density functional theory (DFT) calculations in conjunction with Quantum Espresso code. The stability of the crystal structure XSbF3 compounds is determined by binding energy (Eb) computations. The Eb values for BaSbF3 and RaSbF3 compounds are −19.25 and −20.04eV respectively, indicating that both studied compounds are stable. The optimized lattice constants for BaSbF3 and RaSbF3 compounds are 5.03 and 5.06 Å, respectively. The evaluation of electronic properties is conducted by electronic band structure, total density of states (DOS), and partial density of states (PDOS). It is observed from the PDOS plots that the p-states of Sb and F whereas the d-states of X atoms have the major contribution in the formation of the band structure. Various optical properties have been computed and compared. The static value of ε10 highlights the metallic nature of the studied compounds while RaSbF3 stands out for having the highest recorded value of ε20. The maximum nω values for BaSbF3 and RaSbF3 are 8.46 and 6.86 respectively indicating their potential for photoelectric applications. Furthermore when examining the properties it is evident that the BaSbF3 compound stands out as a material for energy storage because of its higher electron energy at 2.36 KJ/N.mol and lower electron free energy of −2.55 KJ/N.mol compared to the RaSbF3 compound. On the other hand, the RaSbF3 compound is an efficient material for catalysis due to its high ability to absorb heat energy from the external source, as compared to the BaSbF3 compound. This study is the first computational investigation of XSbF3 (X is Ba and Ra) compounds, which provides valuable insights into the physical properties of sb-based fluroperovskites and their potential applications.

How a System Is Closing the Evidence-Based Data Management Gap.

To translate raw data into information that is understandable and actionable, healthcare leaders must leverage decision-making tools that can drive strategic innovation, improve processes, and shape the future of healthcare. Continuous changes in healthcare delivery require constant monitoring of an expanding range of data. Population demographics, psychographics, and availability of care all must be considered, as well as provider practice patterns, patient utilization, clinical and service quality, costs, and many other key variables over time. RWJBarnabas Health is navigating significant changes in its approach to managing data. A unified operating model is driving standardization, continuous quality improvement, and cost reductions across the system. The solution is based on an electronic health record system designed to meet the needs of the entire system, an array of carefully selected external data sources, and a business intelligence tool to enable leaders to quickly draw insights from all the available data.

Koo‐Kleinstreuer‐Li magneto‐nanofluid model for non‐Newtonian micropolar fluid through porous channel

AbstractThe primary concern of writing this article is to study the rheological properties of the micropolar non‐Newtonian nanofluid flowing through the porous medium along with magnetic field effects. In it, the outer boundary of the sheet is heated by applying an external heat source. The insertion of aluminum oxide nanoparticles in water turned it into a nanofluid. Together with the viscous dissipation phenomena, adding a magnetic field has another effect known as a Joule heating impact that is considered in the energy equation. To investigate the impact of viscosity and thermal conductivity on flow patterns, we considered the Koo‐Kleinstreuer‐Li model. A generalized Proudman‐Johnson equation is obtained by using similarity transformation on Navier‐Stokes equations. The well‐known classical shooting method is used to get the numerical solution to the said problem. Graphical results are portrayed for variant rheological parameters lke power law index, Reynolds number, volume fraction, Prandtl number, expansion ratio, and Hartmann number on the velocity and temperature of nanofluids.

A Solar-Blind Ultraviolet Photodetector with Self-Biasing Capability, Controlled by Surface Potential based on GaN Hexagonal Nano-Spikes

In recent years, there’s been growing interest in developing solar-blind self-bias ultraviolet photodetectors for uses like monitoring extreme heat, enhancing security, and improving communications. Gallium-nitride (GaN), known for its ability to detect ultraviolet illumination, is a top choice for making these detectors. In this letter, we introduce a GaN photodetector designed with a hexagonal nano-spikes-like structure that enhances performance and allows it to operate without an external power source. We delve into how surface potential is pivotal in its self-biasing capability. This device shows remarkable performance, including a high responsitivity of 2100 mAW−1 and the ability to detect very weak-signals (4 femto-watts) under self-bias condition. Our findings pave the way to fabricate a GaN-based self-bias optoelectronic device.

Threats to Liberalism in a Nascent Democracy: Authoritarian Encroachment, a Security Dilemma, and a Political-Cultural Deficit

This article offers a complimentary analysis to Prof. Thompson’s treatise on democracy in East Asia. It focuses on the external source of democratic backsliding, a look into the future, and an emphasis on the dilemma of meeting the security challenge while remaining liberal in a world rapidly plunging into Cold War 2.0. Three sources of threat to nascent liberal democracies are identified: authoritarian encroachment, a security dilemma, and a political-cultural deficit. There are striking similarities between the response of a country to external threat and a human body’s response to pathogens (such as SARS-CoV-2). These responses also have similar effects on the survival of the country and the infected person. In order to analyze the relation between a country’s external environment and its polity, a historical account of how the perception of relative security managed to advance liberal political institutions and threats to national security thwarted liberalization in the constitutional development of the Republic of China is offered. This complement ends with a warning about how the world’s plunge into Cold War 2.0 may adversely impact nascent liberal democracies in East Asia that bear the brunt of the rise of an authoritarian China.

Study on detonation characteristics of pulverized coal and evolution law of detonation residue

This study explores the detonation characteristics and compositional changes of pulverized coal, focusing on its use in Rotary Detonation Wave (RDW) technologies. While pulverized coal has shown high fuel efficiency in RDW settings, transitioning from theory to practical detonation engineering presents substantial scientific and technical hurdles. A key issue is the reprocessing of detonation byproducts for in-situ coal mine gob filling, a topic that has received little attention. Utilizing advanced methods like X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR), this paper investigates the micro-morphology, composition, and aromatic structures of gas–solid products pre and post-detonation at the Tashan Coal Mine's 2305 working face. Results indicate that coal dust from the underground mining face has enhanced detonation characteristics, with the addition of coal powder fuel extending the gas detonation limits. This benefits economic aspects by reducing reliance on gas fuel and lowering detonation fuel costs. The highest recorded detonation wave velocity was 2450 m/s, 14.8% greater than that of coal dust from external sources, suggesting more effective energy release and pressure gain. Furthermore, the study links detonation combustion intensity to coal's aromatic properties, noting a post-detonation aromaticity index (I) of 0.4941. This indicates an improvement in the aromatic structure under high-temperature conditions, vital for coal's reactivity and energy efficiency in RDW applications. This research not only deepens the understanding of coal dust combustion mechanisms but also advances clean coal utilization and deep coal fluidization mining, addressing significant RDW technological challenges.

INFLUENCE OF NATURAL FACTORS OF SUPPORTING RESERVOIR PRESSURE AT THE LATE STAGE OF DEVELOPMENT OF GAS CONDENSATE FIELDS

The object of the research is natural factors that can affect both the maintenance of reservoir pressure in the process of developing gas condensate fields and the recovery of depleted deposits. Such factors include: waterflooding of deposits, subsidence of the surface, elasticity of rocks, water and gas, initial gradients of reservoir pressure in deposits, capillary forces. When studying the recovery of reserves in depleted gas condensate fields, it is necessary to take into account the influence of the above factors on the maintenance of reservoir pressure in order to identify the volumes of gas that flow from deep horizons (external sources). The paper shows the dynamics of waterflooding volumes and average reservoir pressures over the years. It is emphasized that waterflooding does not significantly affect the maintenance of reservoir pressure. Correlation dependencies of waterflooding volumes over time and the dependence of waterflooding volumes on reservoir pressure are given. An original system for calculating the volume of the water pressure system is proposed for the purpose of forecasting further waterflooding of deposits. The influences of all the above factors on the process of maintaining reservoir pressure are taken into account. It is shown that for the Shebelinsky GCF, all these factors do not significantly affect the recovery of reserves. The influence of capillary forces and evaporation of water in deposits on the development processes from the point of view of maintaining reservoir pressure at the late stage of GCF operation is studied.

The flavohemoglobin Yhb1 is a new interacting partner of the heme transporter Str3.

Nitric oxide (˙NO) is a free radical that induces nitrosative stress, which can jeopardize cell viability. Yeasts have evolved diverse detoxification mechanisms to effectively counteract ˙NO-mediated cytotoxicity. One mechanism relies on the flavohemoglobin Yhb1, whereas a second one requires the S-nitrosoglutathione reductase Fmd2. To investigate heme-dependent activation of Yhb1 in response to ˙NO, we use hem1Δ-derivative Schizosaccharomyces pombe strains lacking the initial enzyme in heme biosynthesis, forcing cells to assimilate heme from external sources. Under these conditions, yhb1+ mRNA levels are repressed in the presence of iron through a mechanism involving the GATA-type transcriptional repressor Fep1. In contrast, when iron levels are low, the transcription of yhb1+ is derepressed and further induced in the presence of the ˙NO donor DETANONOate. Cells lacking Yhb1 or expressing inactive forms of Yhb1 fail to grow in a hemin-dependent manner when exposed to DETANONOate. Similarly, the loss of function of the heme transporter Str3 phenocopies the effects of Yhb1 disruption by causing hypersensitivity to DETANONOate under hemin-dependent culture conditions. Coimmunoprecipitation and bimolecular fluorescence complementation assays demonstrate the interaction between Yhb1 and the heme transporter Str3. Collectively, our findings unveil a novel pathway for activating Yhb1, fortifying yeast cells against nitrosative stress.

Partial denitrification in rope-type biofilm reactors: Performance, kinetics, and microflora using internal vs. external carbon sources

Stable nitrite accumulation through partial denitrification (PDN) represents an efficient pathway to support the anammox process, but limited studies explored the internal wastewater carbon sources and biofilm processes. This study assessed the viability of the PDN process, biofilm community evolution, and functional enzyme formation in rope-type biofilm media reactors using primary effluent (PE) and anaerobically pretreated wastewater carbon sources for the first time. Comparison was made with external carbon (acetate) under varied pH and biofilm thicknesses, maintaining a favourable sCOD: NO3-N ratio of 3. The wastewater’s internal carbon resulted in thinner biofilms; nevertheless, modest nitrite accumulation (0.24 g/m2/d) occurred only at elevated pH. The highest nitrite accumulation (0.79 g/m2/d) was exhibited in the biofilm thickness-controlled acetate-fed reactor, featuring porous biofilms dominated by denitrifier Thauera (10.24 %) and imbalance between Nar, Nap, and Nir reductases. Using internal wastewater carbon sources offers a sustainable avenue for adopting the PDN process in full-scale application.

Constraining Free–Free Emission and Photoevaporative Mass-loss Rates for Known Proplyds and New VLA–identified Candidate Proplyds in NGC 1977

We present NSF's Karl G. Jansky Very Large Array observations covering the NGC 1977 region at 3.0, 6.4, and 15.0 GHz. We search for compact radio sources and detect continuum emission from 34 NGC 1977 cluster members and 37 background objects. Of the 34 radio-detected cluster members, 3 are associated with known proplyds in NGC 1977, 22 are associated with additional young stellar objects in NGC 1977, and 9 are newly identified cluster members. We examine the radio spectral energy distributions, circular polarization, and variability of the detected NGC 1977 sources and identify 10 new candidate proplyds whose radio fluxes are dominated by optically thin free–free emission. We use measurements of free–free emission to calculate the mass-loss rates of known proplyds and new candidate proplyds in NGC 1977, and find values ∼10−9 to 10−8 M ⊙ yr−1, which are lower than the mass-loss rates measured toward proplyds in the Orion Nebula Cluster but consistent with the mass-loss rates predicted by external photoevaporation models for spatially extended disks that are irradiated by the typical external ultraviolet (UV) fields encountered in NGC 1977. Finally, we show that photoevaporative disk winds in NGC 1977 may be illuminated by internal or external sources of ionization, depending on their positions within the cluster. This study provides new constraints on disk properties in a clustered star-forming region with a weaker UV environment than the Orion Nebula Cluster but a stronger UV environment than low-mass star-forming regions like Taurus. Such intermediate UV environments represent the typical conditions of Galactic star and planet formation.

Simple and Efficient Enantioselective α-Deuteration Method of α-Amino Acids without External Chiral Sources

Simple and Efficient Enantioselective α-Deuteration Method of α-Amino Acids without External Chiral Sources

Dual-Carbon Phase-Encapsulated Prelithiated SiOx Microrod Anode for Lithium-Ion Batteries.

Among silicon-based anode family for Li-ion battery technology, SiOx, a nonstoichiometric silicon suboxide holds the potential for significant near-term commercial impact. In this context, this study mainly focuses on demonstrating an innovative SiOx@C anode design that adopts a pre-lithiation strategy based on in situ pyrolysis of Li-salt of silsesquioxane trisilanolate without the need for lithium metal or active lithium compounds and creates dual carbon encapsulation of SiOC nanodomains by simply one-step thermal treatment. This ingenious design ensures the pre-lithiation process and pre-lithiation material with high-environmental stability. Moreover, phenyl-rich organosiloxane clusters and polyacrylonitrile polymers are expected to serve as internal and external carbon source, respectively. The formation of an interpenetrating and continuous carbon matrix network would not only synergistically offer an improved electrochemical accessibility of active sites but also alleviate the volume expansion effect during cycling. As a result, this new type of anode delivered a high reversible capacity, remarkable cycle stability as well as excellent high-rate capability. In particular, the L2-SiOx@C material has a high initial coulomb efficiencof 80.4% and, after 500 cycles, a capacity retention as high as 97.5% at 0.5 A g-1 with a reversible specific capacity of 654.5mA h g-1.

External and internal sources of cognitive group awareness information: Effects on perception and usage

Group selection or group formation is an important but difficult task in learning groups. Group awareness tools collect, transform, and present group awareness information to provide learners, but also teachers with relevant information e.g., about potential learning partners. For these educational tools, the value and usage of the provided information may depend on how it is gathered and where it ultimately comes from. In our study (N = 150), we thus investigate how information from different sources is perceived and ranked. In the study, information about the skills of an anonymous person in a profile was either provided by external sources (teacher assessment, knowledge test result) or internal sources (self-assessment). Results show that information from external sources is perceived as more credible and weighted higher than internal self-assessed information. No difference between information from external personal teacher assessments and external non-personal knowledge tests was found. Hence, it is worth exploring possible effects of other external ratings than teacher assessments to see if these insights are transferable to other contexts.

Predictive modeling of molds effective elimination by external inactivation sources

Presented paper deals with a novel application of the (nonlinear) logistic equation to model an elimination of microscopic filaments types of fungi-molds from affected materials via different external inactivation techniques. It is shown that if the inactivation rate of the external source is greater than the maximum natural growth rate of mycelium, the mold colony becomes destroyed after a finite time. Otherwise, the mycelium may survive the external attack only at a sufficiently large initial concentration of the inoculum. Theoretically determined growth curves are compared with the experimental data for Aspergillus brasiliensis mold inactivated by using both cold atmospheric plasma (CAP) and UV-germicidal lamp. Model presented in the article may be applied also to other classes of microorganisms (e.g. bacteria).

Influence of Machine Tool Operating Conditions on the Resulting Circularity and Positioning Accuracy

The operating conditions of the production process significantly influence the resulting dimensional and form accuracy of the workpiece. The operating conditions include the position of the workpiece location, with internal and external heat sources influenced not only by the machine location but also by its operation. In addition, there are the cutting conditions and the feed rate requirements of CNC machine tools. These changes, such as workpiece position, feed rates, and machine heat load, are further reflected in the ability of the machine to run at the position required and interpolate within the given tolerances of circularity. For the accuracy and repeatability of positioning, the machine was set up according to ISO 230-2 and for the circular interpolation tests according to ISO 230-4. The obtained results show the importance of attention to the appropriate setting of the operating conditions of the production process, where the knowledge of the geometric accuracy of the CNC machine tool in its working space can systematically increase the manufacturing accuracy itself or be another tool suitable for predicting the dimensional and form accuracy of workpieces.