bluuebunny/crossref_metadata_2025 huggingface dataset:
Thermal-Mechanical Analysis of an Additive Manufacturing Ceramic Heat Exchanger for High-Temperature Recuperator in a sCO2 Power System
Authors: Ma Zhiwen , Jape Sameer , Davenport Patrick , Lipke David
Published: September 2022

Supercritical CO2 (sCO2) Brayton power cycle can be configured in a closed-loop power system and has a potentially high cycle efficiency. Compactness and high efficiency of a sCO2 power block make the sCO2 Brayton cycle a versatile power cycle in broad applications. While many heat sources are of sufficient intensity to produce high temperature working fluids to achieve high cycle efficiency, the thermal-mechanical stability of traditional materials (e.g., steels and nickel-based superalloys) used in construction of heat exchangers and turbine components limits the operating conditions and thus thermodynamic efficiency of the system. This effort seeks to establish the viability of ceramic heat exchanger technologies for the most extreme operating conditions envisioned for power generation and other high temperature processes. Heat exchangers constructed from ultra-high temperature ceramics, a class of extreme environment materials featuring melting points (Tmp.) above 3000°C, is particularly appealing for sCO2 Brayton cycles given their ultra-low creep rates and very high retained strength at low homologous temperatures (i.e., T < 0.5 Tmp., or at least 1500°C). To translate these materials properties to ultra-high temperature heat exchangers, innovations are required in ceramic manufacturing techniques to realize the complex architectures featured in compact heat exchangers with high power density. With appropriate processing, ZrB2-SiC based compositions can be sintered to near full density and shaped into complex topologies via ceramic additive manufacturing methods. This paper analyzes heat exchanger designs and explores thermal-mechanical implications of the operating environment. Thermal flow, heat transfer, and conjugate mechanical analyses provide insights into benefits and risks associated with the design approach.
Online Radiation Experiment on Gamma-Ray Absorption from an Early Quack Device
Authors: Grewal Yugjeet S. , Reynoso Raul Fernando , Reyes Ruben , Walkup John R. , Walkup Michael A.
Published: September 2022

Using a Geiger–Müller tube, sound-capturing software, and a simple computer program, students measured to reasonable precision the half-value layer of steel in absorbing high-energy gamma rays from a Radium Ore Revigator (pronounced re-vig-a-tor with the accent on “vig”), an early quack medical device. This article describes the process used for conducting online radiation exposure experiments as part of an in-class Course-Based Undergraduate Research Experience (CURE) project, with their instructor acting in a more subservient role carrying out actions requested by the students. The manner in which this student-centered approach can drive similar online radiation experiments without compromising student safety is discussed.
Dynamic Energy Transfer Models
Authors: Kubsch Marcus , Hamerski Patti C.
Published: September 2022

Energy is a disciplinary core idea and a cross-cutting concept in the K-12 Framework for Science Education and the Next Generation Science Standards (NGSS). As numerous authors point out, the energy model in these standards emphasizes the connections between energy and systems. Using energy ideas to interpret or make sense of phenomena means tracking transfers of energy across systems (including objects and fields) as phenomena unfold. To support students in progressing towards this goal, numerous representations—both static and dynamic—that describe the flow of energy across systems exist. Static representations work well to describe phenomena where the flow of energy is unidirectional and the dynamics are not a focus but struggle to represent circular energy flows and the temporal order of complex, dynamic phenomena. Existing dynamic representations like Energy Theater are usually qualitative, i.e., they represent energy in ways that differentiate between larger or smaller rates of transfer but do not provide a more detailed quantitative picture. In this article, we present how an existing, empirically tested, static representation called Energy Transfer Model (ETM) can be turned into a dynamic representation that is quantitatively accurate using the freely available 3D animation programming environment GlowScript (https://www.glowscript.org). To do so, we first summarize the central ideas in a model of energy that emphasizes the idea of energy transfer between systems, and we describe how the ETM represents those ideas. Then, we introduce the dynamic ETM and explain how it goes beyond the limitations of its static counterpart and how its quantitative accuracy adds to existing dynamic representations. Lastly, we discuss how the dynamic ETM can be used to integrate computational thinking into the physics classroom.
A High-Speed Test of the Equivalence Principle
Authors: Williams Hollis
Published: September 2022

It is well known that Newton’s work on mechanics depended in a crucial way on the previous observations of Galileo. The key insight of Galileo was that one can analyze the motion of bodies using experiments and mathematical equations. One experimental observation that roughly emerges from this work in modern terms is that two objects of different mass that are simultaneously released from rest and allowed to fall under the influence of gravity through a vacuum should hit the ground at the same time (this is essentially what is called the equivalence principle in general relativity). In popular legend, it is said that Galileo tested this by dropping two balls of different masses from the Leaning Tower of Pisa and showing that they hit the ground at the same time, but the historical evidence suggests that this is unlikely as he seems to have experimented mostly with balls rolling down inclined slopes.
Magnetic Poles: A Missing Manual
Authors: Saslow Wayne Mark
Published: September 2022

This work provides a missing manual needed to understand permanent magnets (also known as “hard” magnets), the only source of magnetic induction field B (units of teslas), often called the magnetic field, that students are familiar with when they confront magnetic force acting on moving charges. Students see this magnetic force in two forms:
Measurement of hydraulic coefficients using a Mariotte bottle and a smartphone
Authors: Ha Hyejin , Jang Taehun , Sohn Sang Ho
Published: September 2022

The Mariotte bottle is a device that delivers a constant flow rate as a result of the constant pressure inside the bottle. This bottle has also been used to study Torricelli’s law, the transition of laminar and turbulent flow, and the capillary interruption of a liquid jet. In fluid mechanics, orifice hydraulic coefficients are essential prerequisites for determining the actual flow of fluid through the orifice. As is well known, when determining the discharge and velocity coefficients of a fluid emitted from a cylinder, maintaining a constant head by continuously supplying the fluid according to the flow rate is difficult.
Classification of simulated complex echoes based on highlight time separation in the bottlenose dolphin (Tursiops truncatus)
Authors: Accomando Alyssa W. , Mulsow Jason , Houser Dorian S. , Finneran James J.
Published: September 2022

Previous studies suggested that dolphins perceive echo spectral features on coarse (macrospectrum) and fine (microspectrum) scales. This study was based on a finding that these auditory percepts are, to some degree, dependent on the dolphin's ∼250-μs auditory temporal window (i.e., “critical interval”). Here, two dolphins were trained to respond on passively detecting a simulated “target” echo complex [a pair of echo “highlights” with a characteristic 120-μs inter-highlight interval (IHI)]. This target had unique micro- and macrospectral features and was presented among “distractor” echoes with IHIs from 50 to 500 μs (i.e., microspectra) and various highlight durations (i.e., macrospectra). Following acquisition of this discrimination task, probe echo complexes with the macrospectrum of the target but IHIs matching the distractors were infrequently presented. Both dolphins initially responded more often to probes with IHIs of 80–200 μs. Response strategies diverged with increasing probe presentations; one dolphin responded to a progressively narrower range of probe IHIs while the second increased response rates for probes with IHIs > 250 μs. These results support previous conclusions that perception of macrospectra for complex echoes is nonconstant as the IHI decreases below ∼100 μs, but results approaching and exceeding 250 μs—the temporal window upper boundary—were more ambiguous.
Water vapor injection into the stratosphere by Hunga Tonga-Hunga Ha’apai
Authors: Vömel Holger , Evan Stephanie , Tully Matt
Published: September 2022

Large volcanic eruptions, although rare events, can influence the chemistry and the dynamics of the stratosphere for several years after the eruption. Here we show that the eruption of the submarine volcano Hunga Tonga-Hunga Ha’apai on 15 January 2022 injected at least 50 teragrams of water vapor directly into the stratosphere. This event raised the amount of water vapor in the developing stratospheric plume by several orders of magnitude and possibly increased the amount of global stratospheric water vapor by more than 5%. This extraordinary eruption may have initiated an atmospheric response different from that of previous well-studied large volcanic eruptions.
NIN-like protein 7 transcription factor is a plant nitrate sensor
Authors: Liu Kun-Hsiang , Liu Menghong , Lin Ziwei , Wang Zi-Fu , Chen Binqing , Liu Cong , Guo Aping , Konishi Mineko , Yanagisawa Shuichi , Wagner Gerhard , Sheen Jen
Published: September 2022

Nitrate is an essential nutrient and signaling molecule for plant growth. Plants sense intracellular nitrate to adjust their metabolic and growth responses. Here we identify the primary nitrate sensor in plants. We found that mutation of all seven
Arabidopsis
NIN-like protein (NLP) transcription factors abolished plants’ primary nitrate responses and developmental programs. Analyses of NIN-NLP7 chimeras and nitrate binding revealed that NLP7 is derepressed upon nitrate perception via its amino terminus. A genetically encoded fluorescent split biosensor, mCitrine-NLP7, enabled visualization of single-cell nitrate dynamics in planta. The nitrate sensor domain of NLP7 resembles the bacterial nitrate sensor NreA. Substitutions of conserved residues in the ligand-binding pocket impaired the ability of nitrate-triggered NLP7 to control transcription, transport, metabolism, development, and biomass. We propose that NLP7 represents a nitrate sensor in land plants.
Heavy-tailed sexual contact networks and monkeypox epidemiology in the global outbreak, 2022
Authors: Endo Akira , Murayama Hiroaki , Abbott Sam , Ratnayake Ruwan , Pearson Carl A. B. , Edmunds W. John , Fearon Elizabeth , Funk Sebastian
Published: September 2022

The outbreak of monkeypox across non-endemic regions confirmed in May 2022 shows epidemiological features distinct from previously imported outbreaks, most notably its observed growth and predominance amongst men who have sex with men (MSM). We use a transmission model fitted to empirical sexual partnership data to show that the heavy-tailed sexual partnership distribution, in which a handful of individuals have disproportionately many partners, can explain the sustained growth of monkeypox among MSM despite the absence of such patterns previously. We suggest that the basic reproduction number (
R
0
) for monkeypox over the MSM sexual network may be substantially above 1, which poses challenges to outbreak containment. Ensuring support and tailored messaging to facilitate prevention and early detection among MSM with high numbers of partners is warranted.
Digital spaces and their perils
Authors: Golbeck Jennifer
Published: September 2022

A pair of books confront the dark sides of virtual communities
Greening national security
The Pentagon, Climate Change, and War
Neta C. Crawford
MIT Press, 2022. 392 pp.
Authors: Belcher Oliver
Published: September 2022

The US military’s eye-watering carbon footprint must be mitigated, argues a political scientist
A coagulation factor moonlights in the heart
Authors: Tong Dan , Hill Joseph A.
Published: September 2022

Liver-derived coagulation factor XI protects the heart from failure
Genomes tell tales of spores versus seeds
Authors: Pennisi Elizabeth
Published: September 2022

Genomes from ferns and a cycad reveal deep roots of plant reproduction
How the Anglo-Saxons settled England
Authors: Curry Andrew
Published: September 2022

Genetic study of burials suggests whole families migrated to the island in the first millennium C.E.
Nucleolar Protein Treacle Is Important for the Efficient Growth of Mumps Virus
Authors: Wakata Aika , Katoh Hiroshi , Kato Fumihiro , Takeda Makoto
Published: September 2022

The nucleolus, which is the site of ribosome biosynthesis, is a target organelle for many viruses. It is increasingly evident that viruses can favor their own replication and multiplication by interacting with various nucleolar factors.
Draft Genome Sequences of Two Basidiomycetous Yeasts, Tremella yokohamensis and Tremella fuciformis
Authors: Chiku Kazuhiro , Sugiyama Shiori , Akimoto Kona , Yoshida Mitsuru
Published: September 2022

In this study, the genome sequences of two Basidiomycetous yeasts,
Tremella yokohamensis
and
Tremella fuciformis
, which have very similar morphological characteristics, were determined. The genomic sequence data obtained will be useful for understanding the taxonomy and metabolic-related genes of basidiomycete yeasts.
Destructive osteomyelitis involvingParvimonas micraandCampylobacter rectus
Authors: Aranowicz Amos , van den Brandt Stephanie L , Slankamenac Ksenija , Keller Dagmar I
Published: September 2022

We present a rare case of destructive osteomyelitis of the sternum caused byParvimonas micraandCampylobacter rectus. A previously healthy female patient in her 40s presented to the emergency department due to a spontaneous rupture of an abscess located to the chest wall. Imaging confirmed abscess formation with osteomyelitis of the sternum. Emergent surgical debridement was performed, blood and bone cultures were taken and the patient received antibiotic treatment. Cultures of the bone and deep tissue revealed infection withParvimonas micraandCampylobacter rectus, both being members of the oral flora and associated with chronic periodontitis. Receiving targeted antibiotic treatment, our patient made a quick recovery. After treatment of the osteomyelitis, our patient was referred to the dentist where chronic periodontitis could be confirmed. Invasive infections withParvimonas micraandCampylobacter rectusare rare. Investigation of a dental origin is crucial to prevent recurrent infections.
Post-reperfusion hyperperfusion after endovascular stroke treatment: a prospective comparative study of TCD versus MRI
Authors: Kneihsl Markus , Hinteregger Nicole , Nistl Oliver , Deutschmann Hannes , Horner Susanna , Poltrum Birgit , Fandler-Höfler Simon , Hatab Isra , Haidegger Melanie , Pinter Daniela , Pichler Alexander , Willeit Karin , Knoflach Micheal , Enzinger Christian , Gattringer Thomas
Published: September 2022

Background

Increased middle cerebral artery (MCA) blood flow velocities on transcranial duplex sonography (TCD) were recently reported in individual patients after successful mechanical thrombectomy (MT) and were related to intracranial hemorrhage and poor outcome. However, the retrospective study design of prior studies precluded elucidation of the underlying pathomechanisms, and the relationship between TCD and brain parenchymal perfusion still remains to be determined.

Methods

We prospectively investigated consecutive patients with stroke successfully recanalized by MT with TCD and MRI including contrast-enhanced perfusion sequences within 48 hours post-intervention. Increased MCA flow on TCD was defined as >30% mean blood flow velocity in the treated MCA compared with the contralateral MCA. MRI blood flow maps served to assess hyperperfusion rated by neuroradiologists blinded to TCD.

Results

A total of 226 patients recanalized by MT underwent post-interventional TCD and 92 patients additionally had perfusion MRI. 85 patients (38%) had increased post-interventional MCA flow on TCD. Of these, 10 patients (12%) had an underlying focal stenosis. Increased TCD blood flow in the recanalized MCA was associated with larger infarct size, vasogenic edema, intracranial hemorrhage and poor 90-day outcome (all p≤0.005). In the subgroup for which both TCD and perfusion MRI were available, 29 patients (31%) had increased ipsilateral MCA flow velocities on TCD. Of these, 25 patients also showed parenchymal hyperperfusion on MRI (sensitivity 85%; specificity 62%). Hyperperfusion severity on MRI correlated with MCA flow velocities on TCD (rs=0.379, p<0.001).

Conclusions

TCD is a reliable bedside tool to identify post-reperfusion hyperperfusion, correlates well with perfusion MRI, and indicates risk of reperfusion injury after MT.
How to set the agenda for training in responsible conduct of research using the target audience as a narrative guide
Authors: Blom Fenneke , Berentsen Susan Maria Johanna , van der Sande Rob
Published: September 2022

There is a growing interest in training on responsible conduct of research (RCR). The availability and range of such training materials, for a diversity of audiences and addressing a diversity of RCR related topics, is growing too. This is of great help to all who are looking for materials to set up their RCR training, but how can one select what topics to include within the often-limited time available for training? In this paper we propose a step-by-step approach to set the agenda for RCR training, using the target audience as a narrative guide. The process consists of six steps: (1) mapping the needs and translating them into learning objectives; (2) prioritizing, selecting, and combining objectives and themes; (3) demarcation of the training; (4) completion of the program; (5) development or adaptation of training materials; and (6) pilot and evaluation. The development process of a training program for researchers in Dutch Universities of Applied Sciences is used as an example to illustrate the step-by-step process.
Analytical study of heat transfer rate of peristaltic flow in asymmetric channel with laser and magnetic effects: Remedy for autoimmune disease
Authors: Nazeer Mubbashar , Irfan Muhammad , Hussain Farooq , Siddique Imran , Khan M. Ijaz , Guedri Kamel , Galal Ahmed M.
Published: September 2022

This paper addresses a hybrid nanoflow of Casson fluid. The theoretical formulation is derived by considering spherical and, as well as, platelet shape nanoparticles. Electro-osmotic flow (EOF) through an asymmetric channel endures the simultaneous effects of Joule heating, viscous dissipation and magnetic fields. Lubrication effects have also been taken into account to subdue the skin friction. Moreover, the contribution of thermal slip boundary conditions and laser radiation articulately devises a theoretical remedy for rheumatoid arthritis. Detailed parametric reveals the promising results for the application of spherical shape nanoparticles to curb autoimmune diseases.
Power law dependence in a random differential equation
Authors: Lv Qiuxin , Ma Wei , Lei Jinzhi
Published: September 2022

This paper studies a random differential equation with random switch perturbations. We explore how the maximum displacement from the equilibrium state depends on the statistical properties of time series of the random switches. We show a power law dependence between the upper bound of displacement and the frequency of random perturbation switches, and the slope of power law dependence is dependent on the specific distribution of the intervals between switching times. This result suggests a quantitative connection between frequency modulation and amplitude modulation under random perturbations.
Investigations of Zr/TiO2-based nanocomposites for efficient plasmonic dye-sensitized solar cells
Authors: Akram Muhammad , Javed Hafiz Muhammad Asif , Ghaffar Abdul , Majeed Muhammad Irfan
Published: September 2022

Renewable energy resources have a wide range of materials to fulfill the energy demand. All developed countries are trying to adopt renewable energy resources to overcome the energy crises. Recent research showed that dye-sensitized solar cells (DSSCs) are optimistic and cheap customers for energy purposes. Most used materials in DSSCs are environment-friendly. Zirconium/titanium dioxide-based nanocomposite photoanodes are mostly stable and efficient for DSSCs. SEM, XRD, UV-visible spectroscopy and Raman spectroscopy were employed to check the morphological, structural and optical properties of Cu and Ag-doped Zr/TiO2, respectively. IV measurements investigation showed that due to the Cu and Ag contents’ effects, the power regeneration efficiency was enhanced by 8.18% by using [Formula: see text] of 0.73 V, [Formula: see text] of 8.78 mA cm[Formula: see text], FF 59.03% and IPCE of 62.43%, due to a shortage in recombinations of charge carrier. The carrier transporting mechanism (EIS) was done at a frequency range of 100 mHz to 1 MHz.
Ribbonlength of twisted torus knots
Authors: Kim Hyoungjun , No Sungjong , Yoo Hyungkee
Published: September 2022

The ribbonlength Rib[Formula: see text] of a knot [Formula: see text] is the infimum of the ratio of the length of any flat knotted ribbon with core [Formula: see text] to its width. A twisted torus knot [Formula: see text] is obtained from the torus knot [Formula: see text] by twisting [Formula: see text] adjacent strands [Formula: see text] full twists. In this paper, we show that the ribbonlength of [Formula: see text] is less then or equal to [Formula: see text] where [Formula: see text] and [Formula: see text] are positive. Furthermore, if [Formula: see text], then the ribbonlength of [Formula: see text] is less then or equal to [Formula: see text].
A combinatorial description of the LOSS Legendrian knot invariant
Authors: He Dongtai , Truong Linh
Published: September 2022

In this paper, we observe that the hat version of the Heegaard Floer invariant of Legendrian knots in contact three-manifolds defined by Lisca-Ozsváth-Stipsicz-Szabó can be combinatorially computed. We rely on Plamenevskaya’s combinatorial description of the Heegaard Floer contact invariant.
Existence and uniqueness of the mild solution of an abstract nonlocal semilinear fractional integrodifferential equation
Authors: Herzallah Mohamed A. E. , Radwan Ashraf H. A.
Published: September 2022

The purpose of this paper is to study the existence and uniqueness of mild solutions to a semilinear Cauchy problem for an abstract nonlocal fractional integrodifferential equation, which has a distinctive nonlinear term. Two sufficient conditions on the existence of mild solutions will be displayed. Continuous dependence of solutions on initial conditions and local [Formula: see text]-approximate mild solutions will be discussed. An example will be given to elucidate the main results. The results obtained are based upon the method of semigroups, contraction mapping principle, and Krasnoselskii’s fixed point theorem.
Byzantine Fault Tolerance For Distributed Ledgers Revisited
Authors: Wang Yongge
Published: September 2022

The problem of Byzantine Fault Tolerance (BFT) has received a lot of attention in the last 30 years. Due to the popularity of Proof of Stake (PoS) blockchains in recent years, several BFT protocols have been deployed in the large scale of Internet environment. We analyze several popular BFT protocols such as Capser FFG/CBC-FBC for Ethereum 2.0 and GRANDPA for Polkadot. Our analysis shows that the security models for these BFT protocols are slightly different from the models commonly accepted in the academic literature. For example, we show that, if the adversary has a full control of the message delivery order in the underlying network, then none of the BFT protocols for Ethereum blockchain 2.0 and Polkadot blockchain could achieve liveness even in a synchronized network. Though it is not clear whether a practical adversary could
actually
control and re-order the underlying message delivery system (at Internet scale) to mount these attacks, it raises an interesting question on security model gaps between academic BFT protocols and deployed BFT protocols in the Internet scale. With these analysis, this article proposes a Casper CBC-FBC style binary BFT protocol and shows its security in the traditional academic security model with complete asynchronous networks. For partial synchronous networks, we propose a multi-value BFT protocol BDLS based on the seminal DLS protocol and show that it is one of the most efficient practical BFT protocols at large scale networks in the traditional academic BFT security model. The implementation of BDLS is available at
https://github.com/yonggewang/bdls
. Finally, we propose a multi-value BFT protocol XP for complete asynchronous networks and show its security in the traditional academic BFT security model.
A Scalable Trustworthy Infrastructure for Collaborative Container Repositories
Authors: Wei Franklin , Tate Stephen , Ramkumar Mahalingam , Mohanty Somya
Published: September 2022

Within cloud computing containerization has become ubiquitous. As the availability of pre-built containers increases there is a need for methods capable of efficiently securing large repositories of software containers. We present a “Trustworthy Container Repository” (TCR) system which provides security assurances (confidentiality, integrity, and authenticity) regarding such a repository in a scalable manner. Trust within the TCR architecture is rooted in a low-complexity, tamper-resistant trusted module, which leverages index-ordered Merkle trees (IOMTs) to efficiently track a large number of container images and provide assurances of repository integrity to its users. The key contributions of the study are, identification of the required security model, a novel TCR data-structure, and verifiable algorithms to operate on it. Through experiment, we observe closely logarithmic time complexity of the proposed system up to a high container count (
N
= 2
25
≈ 10
7
).
Iron and the Pathophysiology of Diabetes
Authors: Harrison Alexandria V. , Lorenzo Felipe Ramos , McClain Donald A.
Published: September 2022

High iron is a risk factor for type 2 diabetes mellitus (T2DM) and affects most of its cardinal features: decreased insulin secretion, insulin resistance, and increased hepatic gluconeogenesis. This is true across the normal range of tissue iron levels and in pathologic iron overload. Because of iron's central role in metabolic processes (e.g., fuel oxidation) and metabolic regulation (e.g., hypoxia sensing), iron levels participate in determining metabolic rates, gluconeogenesis, fuel choice, insulin action, and adipocyte phenotype. The risk of diabetes related to iron is evident in most or all tissues that determine diabetes phenotypes, with the adipocyte, beta cell, and liver playing central roles. Molecular mechanisms for these effects are diverse, although there may be integrative pathways at play. Elucidating these pathways has implications not only for diabetes prevention and treatment, but also for the pathogenesis of other diseases that are, like T2DM, associated with aging, nutrition, and iron.
Fabrication of Novel 3D Star-Like PbO2 Nanospheres for Enhanced Electrochemical Ozone Production
Authors: Wang Xi , Wu Dandan , Wang Luyang , Wu Xu
Published: September 2022

The star-like PbO2 nanostructure was successfully synthesized via a template-free water bath route. SEM, TEM and XRD were employed to characterize the crystalline structures and morphological properties of the PbO2 obtained. A multistep growth process is proposed to form the three-dimensional star-like structure. In addition, the star-like PbO2 showed higher catalytic activity for EOP (electrochemical ozone production) than commercial lead dioxide particles. The energy consumption per unit ozone of the star-like PbO2-based electrolyser is reduced by 41.15% than that of the commercial PbO2. This result may be relevant to, 3D star-like structure’s exposed catalytic active sites, its rapid charge transfer ability, and the ample space between adjacent flakes that ensures the sufficient mass transfer ability. This work proposes a new strategy of fabricating star-like PbO2 nanomaterials which have high catalytic activity for EOP.
Chronic moderate hypercapnia suppresses ventilatory responses to acute CO2 challenges
Authors: Buchholz Kirstyn J. , Neumueller Suzanne E. , Burgraff Nicholas J. , Hodges Matthew R. , Pan Lawrence , Forster Hubert V.
Published: September 2022

Moderate levels of chronic hypercapnia (CH; ∼70 mmHg) in healthy adult female goats elicited similar steady-state physiological adaptations compared with mild CH (∼55 mmHg). However, unlike mild CH, moderate CH chronically suppressed acute CO2/[H+] chemosensitivity and reversed the arterial to mixed expired CO2 gradient. These findings suggest that moderate CH suppresses vital mechanisms of ventilatory control and recruits additional physiological systems (i.e., gastric CO2 release) to help buffer excess CO2.
Correlation of Tryptophan Metabolic Pathway with Immune Activation and Chemosensitivity in Patients with Lung Adenocarcinoma
Authors: Wang Zheng , Liu Danni , Yang Rongjie
Published: September 2022

Lung adenocarcinoma (LUAD) is the most common type of lung cancer with high malignancy and easy metastasis in the early stage. In this study, we aimed to figure out the role of tryptophan metabolic pathway in LUAD prognosis and treatment. Different molecular subtypes were constructed based on tryptophan metabolism-related genes. Significant prognostic genes and clinical prognostic characteristics, immune infiltration level, and pathway activity in different subtypes were determined by algorithms, such as the least absolute shrinkage and selection operator (Lasso), CIBERSORT, Tumor Immune Dysfunction and Exclusion (TIDE), and gene set enrichment analysis (GSEA). The effect of different gene mutation types on the prognosis of patients with LUAD was explored. The clinical prognosis model was constructed and its reliability was verified. Of the 40 genes in the tryptophan metabolism pathway, 13 had significant prognostic significance. Based on these 13 genes, three molecular subtypes (C1, C2, and C3) were established. Among them, C1 had the worst prognosis and the lowest enrichment score of tryptophan metabolism. At the same time, C1 had the most genetic variation, the highest level of immune infiltration, and significantly activated pathways related to tumor development. The high-risk and low-risk groups had significant differences in prognosis, immune infiltration and pathway enrichment, which was consistent with the results of subtype analysis. Mutation in tryptophan metabolism-related genes leads to abnormal tryptophan metabolism, immune deficiency, and activation of cancer-promoting pathways. This results in high malignancy, poor prognosis, and failure of traditional clinical treatments. Through the establishment of risk score (RS) clinical prognosis model, we determined that RS could reliably predict the prognosis of patients with LUAD.
IoT-Oriented Distributed Intrusion Detection Methods Using Intelligent Classification Algorithms in Spark
Authors: Xu Qiang , Jia Xiteng , Jia Bin , Liang Yongquan
Published: September 2022

With the rapid development and wide application of the 5G mobile communication and the explosive security threats of the Internet of things (IoT), distributed intrusion detection is one of the hot topics in the intrusion detection field of network security. The classification algorithm is a kind of the most representative and classical algorithms of artificial intelligence (AI), and it is an important technique for intrusion detection in order to distinguish the attack traffic from massive network data. In order to solve the problem to detect massive and complex network attack traffic in IoT, in this study, we propose the distributed intrusion detection framework and method using intelligent classification algorithms in Spark. We first introduce several mainstream classification algorithms provided by Spark. Second, the distributed intrusion detection procedure using intelligent classification algorithms is given. Next, the overall framework of the proposed model is built. Finally, a series of comparison experiments by the binary classification and quintuple classification in six evaluation indicators (i.e., recall, precision, F1-score, FNR, FPR, and ROC curve) indicate that the naive Bayes has a worse classification performance than that of other classification algorithms, and the classification effect in a cluster environment is almost the same as that in a stand-alone environment.
Khat (Catha edulis) Leaf Extract‐Based Zinc Oxide Nanoparticles and Evaluation of Their Antibacterial Activity
Authors: Aklilu Muluken , Aderaw Temesgen
Published: September 2022

In this study, we used khat (Catha edulis) leaf extract as a reducing and stabilizing agent for the biosynthesis of zinc oxide nanoparticles (ZnO NPs). The rapid color change of the solution to pale yellow and UV‐visible absorption peak at 322 nm confirmed the initial formation of ZnO NPs. FTIR spectrum analysis revealed the contribution of khat leaf extract to the bioreduction of Zn2+ ions to ZnO NPs. The FTIR spectrum for the stretching vibration of ZnO at 480 cm-1 also confirms the formation of ZnO NPs. The XRD spectrum showed the crystallinity and the hexagonal wurtzite structure of ZnO NPs. The size of the synthesized ZnO NPs calculated using the Debye‐Scherrer formula was found to be equal to 17 nm. Antibacterial efficacy of green‐produced zinc oxide nanoparticles against Gram‐positive and Gram‐negative microorganisms was tested. It has the greatest inhibition zone (23 mm) against E. coli, but the least activity was against S. pneumoniae (15 mm).
Review of Short-Term Load Forecasting for Smart Grids Using Deep Neural Networks and Metaheuristic Methods
Authors: Islam Badar ul , Rasheed Maria , Ahmed Shams Forruque
Published: September 2022

Forecasting electricity load demand is critical for power system planning and energy management. In particular, accurate short-term load forecasting (STLF), which focuses on the lead time horizon of few minutes to one week ahead, can help in better load scheduling, unit commitment, and cost-effective operation of smart power grids. In the last decade, different artificial intelligence (AI)-based techniques and metaheuristic algorithms have been utilized for STLF by the researchers and scientists with varying degrees of accuracy and efficacy. Despite the benefits of implemented methods for STLF, many drawbacks and associated problems have also been observed and reported by the researchers. This paper provides a comprehensive review of hybrid deep learning models based on nature-inspired metaheuristic techniques for STLF with respect to the analysis of the results and accuracy. Moreover, it also provides the research findings and gaps that will assist the researchers to have an early awareness of all important benefits and drawbacks of these integrated STLF methods scientifically and systematically. Especially, the hybrid forecast models using artificial intelligence-based methods for smart grids are focused. Several performance indices are used to compare and report the accuracy of these techniques including mean absolute percentage error (MAPE). Multiple other parametric and exogenous variable details have also been focused to figure out the potential of the intelligent load forecasting techniques from the perspective of smart power grids.
Research on Intelligent Production Line Design and Dynamic Balance for 3C Products
Authors: Feng Lingyun
Published: September 2022

An intelligent production line design scheme for 3C products is introduced amid the current situation of low automation in assembly, testing, packaging and other production contacts in the 3C manufacturing industry, high demand for upgrades and fierce market competition, taking a 3C electronic product as an example to investigate its overall layout, workstation structure, architecture system and control system. In addition, according to the concept of lean production, a method is proposed to realize dynamic balance of production line. First of all, the dynamic balance mathematical model is established, then the genetic algorithm is used to solve the model parameters, and finally the production line can keep the balance by adjusting the running speed of field equipment according to the calculation results. The actual verification shows that the production line runs stably, completes the automatic and intelligent production of products, with a balance rate at an excellent level. This can serve as a reference for relevant enterprises to build intelligent production lines for 3C products and implement lean production.
Equilibria and Bogdanov‐Takens Bifurcation Analysis in the Bazykin’s Predator‐Prey System
Authors: Wang Shuangte , Yu Hengguo
Published: September 2022

In the paper, we proposed a Bazykin’s predator‐prey system to explore the equilibrium point and Bogdanov‐Takens bifurcation problems. Firstly, we derived some key parameter threshold conditions to ensure that the Bazykin’s predator‐prey system had a multiple focus of multiplicity one, weak focus of order 2, cusps of codimension 2 and a degenerate Bogdanov‐Takens singularity (focus or center case) of codimension 3. Furthermore, the distinction of two types of codimension 2 cusps was also discussed, which showed that the threshold of the two types of cusps could exhibit a cusp, which was a special case of the mentioned degenerate Bogdanov‐Takens singularity (focus or center case) of codimension 3. Secondly, we systematically calculated that the Bazykin’s predator‐prey system could undergo two types of Bogdanov‐Takens bifurcations of codimension 2 and a degenerate focus type Bogdanov‐Takens bifurcation of codimension 3. Finally, some numerical examples were implemented to verify the correctness and feasibility of mathematical theory derivation, which also directly showed all possible equilibrium points and Bogdanov‐Takens bifurcations of Bazykin’s predator‐prey system. In a word, all the research results could play an important theoretical support role in the study of controlling cyanobacteria bloom.
Delayed Surgery to Preserve Kidney with Grade IV Injury
Authors: Li YunPeng , Xiao Long , Xu WanChao , Zhao Liangyun , Xiao MinHui
Published: September 2022

Background. Since the introduction of the ALARA (“as low as reasonably achievable”) concept, the management of severe renal trauma has shifted. Our hospital promotes delayed surgical intervention for grade IV closed renal injury, to preserve renal function. In this study, we retrospectively reviewed the management and outcomes of patients with grade IV closed renal injury in our hospital. Objective. To evaluate the management and outcome of grade IV closed renal injury. Methods. We retrospectively reviewed the medical records of 45 patients with grade IV closed renal injury; namely, 36 men and 9 women with an average age of 35.6 years. All patients were diagnosed with grade IV closed renal injury in accordance with the guidelines of the American Association for the Surgery of Trauma. All hemodynamically-stable patients with renal trauma were treated conservatively for approximately 13 days and then underwent surgery only to clear the perirenal hematoma and not to repair or resect the affected kidney. Abstracted data included patient demographics, mechanism of injury, admission hemodynamics, CT findings, and mortality. The primary outcome was the success rate of nonsurgical treatment, and the secondary outcome was the complication of nonsurgical treatment. Results. All patients responded and were discharged, and no patients died. We followed 35 (77.8%) patients for at least 1 year. One patient with partially devitalized renal parenchyma underwent surgery to remove the affected kidney. Eleven patients (31.4%) suffered complications, namely, three (8.6%) cases of hypertension, four (11.4%) cases of hematuria, two cases (5.7%) of urinary tract infection, and two (5.7%) cases of urinoma. Conclusions. Delayed exploratory surgery only to remove the hematoma should be considered in hemodynamically-stable patients with grade IV closed renal injury. This approach can avoid high nephrectomy rates associated with emergency surgery and reduce the complications that result from conservative treatment without surgery.
Correlation between Serum ApoC III and Galectin-3 Levels and Maternal and Neonatal Adverse Outcomes in Gestational Diabetes Mellitus Patients
Authors: Tang Tingting , Chen Liguang
Published: September 2022

Objective. The correlation between serum ApoC III and galectin-3 levels and adverse maternal and infant outcomes in GDM patients was analyzed. Methods. A total of 97 GDM patients admitted to our hospital from January 2019 to June 2021 were selected and divided into a good group and a poor group according to the pregnancy outcomes, ApoC III in blood of subjects was detected by immunoturbidimetry, and galectin-3 level was detected by enzyme-linked immunosorbent assay. Spearman correlation test was used to analyze the correlation between ApoC III and galectin-3 levels and pregnancy outcomes in patients with GDM, and ROC curves were drawn to analyze the value of each index alone and in combination to predict pregnancy outcomes in patients with GDM. Results. The levels of ApoC III and galectin-3 in the blood of the patients in the bad group were significantly higher than those in the good group, and the difference was statistically significant (t = 11.231, 14.965,

P
<
0.05

). The levels of ApoC III and galectin-3 in the blood of GDM patients were significantly positively correlated with adverse pregnancy outcomes, and there was a statistical significance (r = 0.754 and r = 0.698,

P
<
0.05

). The combined application of ApoC III and galectin-3 levels in GDM patients’ blood to predict the adverse outcome of pregnancy was Log

P
=
0.623

,

∗

ApoC III+0.605

∗

galectin-3. The sensitivity, specificity, and AUC of combined application of ApoC III and galectin-3 for predicting adverse pregnancy outcomes in GDM patients were all greater than 90%, and AUC>0.90. The combined application in predicting adverse pregnancy outcomes were higher than those of the individual indicators, and the difference was statistically significant (

P
<
0.05

). Conclusion. The levels of ApoC III and galectin-3 in the blood of GDM patients with adverse pregnancy outcomes were significantly increased, and the detection of ApoC III and galectin-3 could effectively improve the value of predicting adverse pregnancy in GDM.
Effects of 15th January 2010 Annular Solar Eclipse on Traveling Ionospheric Disturbances and Equatorial Plasma Bubbles over Low Latitude Regions of East Africa
Authors: Athwart Davis Odhiambo , Ndinya Boniface , Baki Paul
Published: September 2022

The influence of the 15th January 2010 annular solar eclipse on traveling ionospheric disturbances (TIDs) and equatorial plasma bubbles (EPBs) is studied using data from six global navigation and satellite system (GNSS) receivers spread across the path of annularity over the low latitude region of East Africa. The GNSS receivers are stationed at Nairobi (RCMN), Malindi (MAL2), and Eldoret (MOIU) in Kenya; Mbarara (MBAR) in Uganda; Kigali (NURK) in Rwanda; and Mtwara (MTWA) in Tanzania. The study period ranges from 12th to 18th January 2010, three days before and after the 15th January 2010 annular solar eclipse. The year 2010 marked the beginning phase of solar cycle 24, evidently observed in low total electron content (TEC) values and the disturbed storm time index (Dst). The eclipse started at 7 : 06 LT and ended at 10 : 14 LT, with MOIU and RCMN experiencing eclipse magnitudes of 0.946 and 0.93, respectively. The maximum obscuration occurred between 8 : 21 LT and 8 : 34 LT across most of the stations. A detrending on vertical TEC (VTEC) derived from GNSS receivers across or close to the path of totality revealed a reduction of ∼2-3 TECU during the maximum phase of the eclipse. The level of reduction was highly close to the totality path and decreased smoothly away from the totality path. Using a background polynomial fitting technique on diurnal TEC, we analyzed TIDs along NURK-MBAR-MOIU and MOIU-RCMN-MAL2 GPS arrays. The results revealed a wavelike perturbation with a virtual horizontal velocity of 830m/s and ∼1 TECU amplitude propagating eastward along the MOIU-RCMN-MAL2 GPS array. The study reports a moderate scintillation activity of 0.5 ≤ ROTI ≤ 0.9 values, demonstrating the presence of few EPBs over the region. The results show a latitudinal variation in GPS-TEC scintillation activities and suggest a possible influence of the eclipse on the observed increase in average scintillation levels across East Africa.
Improvement and Reduction of Self-Heating Effect in AlGaN/GaN HEMT Devices
Authors: Chen Hui , Tang Naiyun , Zuo Zhipeng
Published: September 2022

GaN is one of the third-generation broadband semiconductor materials developed rapidly in recent years, and Algan/GanHEMT has a broad application prospect in the fields of high temperature, high power, high frequency and radiation resistance, etc. In recent years, gallium nitride based high electron mobility transistors have been widely used in emerging industries, such as 5G technology, new energy vehicles, unmanned aircraft and other fields, due to their high power and high voltage resistance. However, due to the high power density of HEMT devices, the self-heating effect will lead to a significant increase in the junction temperature of the device, which will seriously affect the performance, reliability, and lifetime of the device. In this paper, the temperature characteristics of GaN high electron mobility transistors (GaN HEMTs) are studied, and the effect of self-heating effect on GaN HEMT devices is analyzed. In order to reduce the device temperature and improve the reliability of the device, a new device structure is proposed in this paper. The new structure replaces the conventional silicon and Si3N4 with highly thermally conductive diamond and SiC as the substrate and passivation layer of the device, which facilitates the heat dissipation from the substrate and passivation layer. Also, the new structure employs a hybrid barrier layer and field plate. Simulation results show that the new structure has about 30% lower temperature peak, 47% higher output current, 28% higher transconductivity, and up to 18.22% higher current collapse rate compared to the conventional structure.