bluuebunny/crossref_metadata_2025 huggingface dataset:
Kinetics and coexistence of autocatalytic reaction cycles
Authors: Könnyű Balázs , Szathmáry Eörs , Czárán Tamás , Szilágyi András
Published: August 2024

Biological reproduction rests ultimately on chemical autocatalysis. Autocatalytic chemical cycles are thought to have played an important role in the chemical complexification en route to life. There are two, related issues: what chemical transformations allow such cycles to form, and at what speed they are operating. Here we investigate the latter question for solitary as well as competitive autocatalytic cycles in resource-unlimited batch and resource-limited chemostat systems. The speed of growth tends to decrease with the length of a cycle. Reversibility of the reproductive step results in parabolic growth that is conducive to competitive coexistence. Reversibility of resource uptake also slows down growth. Unilateral help by a cycle of its competitor tends to favour the competitor (in effect a parasite on the helper), rendering coexistence unlikely. We also show that deep learning is able to predict the outcome of competition just from the topology and the kinetic rate constants, provided the training set is large enough. These investigations pave the way for studying autocatalytic cycles with more complicated coupling, such as mutual catalysis.
Comparison of bioactive material failure rates in vital pulp treatment of permanent matured teeth – a systematic review and network meta-analysis
Authors: Komora Péter , Vámos Orsolya , Gede Noémi , Hegyi Péter , Kelemen Kata , Galvács Adél , Varga Gábor , Kerémi Beáta , Vág János
Published: August 2024

Mineral Trioxide Aggregate (MTA) is the gold standard for vital pulp treatment (VPT), but its superiority over novel calcium silicate-based cements in permanent teeth lacks systematic evidence. This study aimed to compare the efficacy of these materials in VPT through a network meta-analysis. A systematic search was conducted in MEDLINE, EMBASE, Cochrane Library, and Web of Science until January 20, 2024. The inclusion criteria were randomized controlled trials involving VPT with biomaterials and reversible or irreversible pulpitis diagnoses in mature permanent teeth. The primary outcome was the odds ratio (OR) of failure rates with 95% confidence intervals. In the 21 eligible trials, failure rates were significantly higher with calcium-hydroxide than MTA at six (OR 2.26 [1.52-3.36]), 12 (OR 2.53 [1.76-3.62]), and 24 months (OR 2.46 [1.60-3.79]). Failure rates for Totalfill at six (OR 1.19 [0.55-2.58]) and 12 months (OR 1.43 [0.71-2.92]), and Biodentine at six (OR 1.09 [0.66-1.78]), 12 (OR 1.21 [0.74-1.96]), and 24 months (OR 1.47 [0.81-2.68]) were not significantly different from MTA. The results were similar in the direct pulp capping subgroup, whereas, in the partial and full pulpotomy subgroup, there was not enough evidence to achieve significant differences. MTA, Biodentine, and Totalfill are the most efficient materials for VPT. However, calcium-hydroxide-based materials are not recommended in VPT.
Force reflections of auditory and tactile action-effect weighting in motor planning
Authors: Horváth János
Published: August 2024

Most voluntary actions have only few goals, which provides considerable freedom in the selection of action parameters. Recent studies showed that task-irrelevant aspects of the task context influence the motor parameters of the actions in a way which seems to reflect the relative importance of these aspects within the underlying action representation. The present study investigated how the intensity of auditory action-effects affected force exertion patterns in a self-paced action production task. Participants applied force impulses with their index finger on a force-sensitive resistor every three seconds. In four separate conditions, force impulses elicited no sound, or elicited tones with 69, 59 or 49 dB intensity. The results showed that participants applied more force when tone intensity was lower, and when tones were absent. These force differences were also present in the first 60 ms following tone onset, implying that these reflected differences in motor planning. The results are compatible with the notion that actions are represented in terms of their sensory effects, which are weighted differently—presumably to maintain an optimal level of overall auditory and tactile stimulation in the present case. These results hint at the potential usefulness of motor parameters as readouts of action intentions.
Light-up covalent organic frameworks with flexible wall design for chemical sensing
Authors: Zhao Wanyi , Xing Ce , Zhang Yuwei , Ren Juntao , Li He
Published: August 2024

Two imine-based COFs with flexible channels were synthesized, showing high sensitivity and selectivity towards nitro-explosives.
Transferable machine learning interatomic potential for carbon hydrogen systems
Authors: Faraji Somayeh , Liu Mingjie
Published: August 2024

In this study, we developed a machine learning interatomic potential based on artificial neural networks (ANN) to model carbon–hydrogen (C–H) systems.
Photoisomerization pathways of trans-resveratrol
Authors: Yoshinaga Mariana , Toldo Josene M. , Rocha Willian R. , Barbatti Mario
Published: August 2024

The photophysical exploration of trans-resveratrol reveals internal conversion pathways, including a novel route leading to a closed-ring derivative. This study utilizes an “explore-then-assess” strategy combining nonadiabatic dynamics and high-level theoretical evaluations.
Layerwise replacement method to achieve high solar-to-hydrogen efficiency for photocatalytic water splitting: a first principles study
Authors: Quan Chuye , Ji Shilei , Yao Ruijia , Du Ming , Chen Chen , He Xiaoyang , Cai Ran , Yang Jianping , Li Xing'ao
Published: August 2024

LRM can purposefully modulate the bandgap of atomically layered stacking materials and reconstruct their intrinsic electric field, thereby regulating the STH efficiency, and driving force of photogenerated carriers of the materials.
Enhancing lithium storage rate and durability in sphalerite GeP by engineering configurational entropy
Authors: Li Yanhong , Wang Jeng-Han , Liu Tzu-Yu , Li Xinwei , Guo Zaiping , Liu Meilin , Li Wenwu
Published: August 2024

High-entropy sphalerite-structured compounds, derived from cubic GeP, demonstrate remarkable metallic conductivity and superior lithium-storage capabilities when compared to the parent phases of monoclinic layered GeP or SiP.
Bifidobacterium animalis subsp. lactis CCFM1274 relieved allergic asthma symptoms by modifying intestinal tryptophan metabolism in mice
Authors: Wang Hongchao , He Yuan , Dang Danting , Feng Ling , Huang Liming , Zhao Jianxin , Lu Shourong , Lu Wenwei
Published: August 2024

CCFM1274 remodeled intestinal tryptophan metabolism in mice and contributed to the improvement of allergic asthma through downregulating the levels of OVA-sIgE, IL-10 and IL-17 in BALF and upregulating the relative abundance of Bifidobacterium.
The alleviative effects of viable and inactive Lactobacillus paracasei CCFM1120 against alcoholic liver disease via modulation of gut microbiota and the Nrf2/HO-1 and TLR4/MyD88/NF-κB pathways
Authors: Niu Ben , Feng Yingxuan , Cheng Xu , Xiao Yue , Zhao Jianxin , Lu Wenwei , Tian Fengwei , Chen Wei
Published: August 2024

Probiotics can alleviate alcoholic liver disease.
Exploring the influence of mesoporosity in hard carbon-templated hierarchical SAPO-5 for ethanol dehydration
Authors: Potter Matthew E. , McShane Evangeline B. , Visser Nienke L. , Meeldijk Johannes D. , Allen Lisa J. , King Stephen M. , Carravetta Marina , de Jongh Petra E. , Vandegehuchte Bart D. , Raja Robert
Published: August 2024

Carbon nanotemplates are used to create hierarchical silicoaluminophosphate materials, with superior catalytic performance to microporous materials. Their hierarchical nature is probed with in-depth microscopy and small-angle neutron scattering.
Synthesis of a tube-like tetra-bipyridyl, tetra-ethylacetato-calix[4]arene in 1,3-alternate conformation and the unexpected crystal structure of its [bpy(CoCl2)]3-[bpy(CoCl2)(H2O)] complex
Authors: Mourer Maxime , Bouizi Younes , Leclerc Sébastien , Malaman Bernard , Regnouf de Vains Jean-Bernard
Published: August 2024

A new tetra-cobalt complex of a tetra-bipyridyl-calix[4]arene in the 1,3-alternate conformation has been prepared and characterized, notably by UV and NMR spectroscopies and X-ray diffraction studies.
Co3O4–CuO bimetallic catalyst activated PMS to degrade LEV in wastewater: the existence of dual degradation mechanisms
Authors: Jia Xiaoning , He HaiXin , Zhao Xia , Li Yabin , Wang Chunxiang , Yang Yanhui , Wu Jingwen
Published: August 2024

In the CCO/PMS system, the degradation process of LEV predominantly relies on a dual degradation mechanism, with the primary pathway being non-radical (1O2) and the supplementary pathway being radical (˙OH and SO4˙−).
Coordination of ruthenium phthalocyanine with poly(4-vinylpyridine)
Authors: Cruz Menandro V. , Cyr Melanie , Boughanmi Habiba , García-Calvo José , Brusso Jaclyn , Torres Tomás , Lessard Benoît H.
Published: August 2024

Ruthenium phthalocyanine (RuPc) based polymers to control the solubility, film formation and self assembly.
Facile synthesis of asymmetric molecular brushes with triple side chains using a multivalent monomer strategy
Authors: Cao Shiya , Liu Wenyi , Yang Bicai , Zheng Yuan , Lin Shaoliang , Xu Binbin
Published: August 2024

Heterografted molecular brushes comprising three different brushes were synthesized based on the Br-acrylate-epoxide multivalent monomer strategy, which enabled the fabrication of 2D platelets and the stabilization of different emulsions.
A surface defect strategy of NiCo-layered double hydroxide decorated MXene layers for durable solid-state supercapacitors
Authors: Wei Jinhe , Hu Fei , Lv Chenglong , Bian Limin , Liu He , Ouyang Qiuyun
Published: August 2024

The aggregation and self-stacking of MXenes and layered double hydroxides (LDHs) in the electrode preparation process are considered the primary obstacles to their practical applications.
Modern photo- and electrochemical approaches to aryl radical generation
Authors: Grudzień Krzysztof , Zlobin Andrei , Zadworny Jan , Rybicka-Jasińska Katarzyna , Sadowski Bartłomiej
Published: August 2024

This review describes recent advances in the generation of aryl radicals using light and electricity. Such modern techniques allow for efficient energy and resource utilization, thus providing more sustainable radical arylation methods.
2-Chloro-3-cyano-4-nitrobenzyl pyridinium bromide as a potent anti-lung cancer molecule prepared using a single-step solvent-free method
Authors: Govindaraj Sadaiyan , Ganesan Kilivelu , Elumalai Perumal , Jeevitha Rajanathadurai , Subramani Annadurai , Amanullah Mohammed , Al-Samghan Awad Saeed
Published: August 2024

Mono-/dimeric-substituted pyridinium and pyrazolium bromides were prepared under conventional and solvent-free silica-supported domestic microwave conditions.
Design of a double-layered material as a long-acting moisturizing hydrogel–elastomer and its application in the field protection of elephant ivories excavated from the Sanxingdui Ruins
Authors: Jiang Lang , Xiang Shilin , Ji Xiaoying , Lei Jinshan , Li Dongliang , Li Sifan , Xiao Lin , Jiang Luman , Zhao Lijuan , Wang Yi
Published: August 2024

Hydrogel-elastomer possess long-term moisture retention and superior mechanical properties. It offers a transparent, flexible, strong alternative for effective protection of wet cultural relics like unearthed ivory.
Comparison of the analytical performance of two different electrochemical sensors based on a composite of gold nanorods with carbon nanomaterials and PEDOT:PSS for the sensitive detection of nitrite in processed meat products
Authors: Wahyuni Wulan Tri , Rahman Hemas Arif , Afifah Salmi , Anindya Weni , Hidayat Rayyan Azzahra , Khalil Munawar , Fan Bingbing , Putra Budi Riza
Published: August 2024

Herein, two platforms for electrochemical sensors were developed based on a combination of gold nanorods (AuNRs) with electrochemically reduced graphene oxide (ErGO) or with multiwalled carbon nanotubes (MWCNTs) and PEDOT:PSS for nitrite detection.
Reactivity of the phosphaethynolate anion with stabilized carbocations: mechanistic studies and synthetic applications
Authors: Nguyen Thi Hong Van , Chelli Saloua , Mallet-Ladeira Sonia , Breugst Martin , Lakhdar Sami
Published: August 2024

Kinetics and computational studies enabled understanding the ambident reactivity of the sodium phosphaethynolate anion and have led the discovery of new reactivity with stabilized carbocations.
3D-printed electrochemical cells for multi-point aptamer-based drug measurements
Authors: Mack John , Murray Raygan , Lynch Kenedi , Arroyo-Currás Netzahualcóyotl
Published: August 2024

Proof-of-concept for a 3D-printed multielectrode device allowing four parallel measurements in sub-mililiter sample volumes. This cell is compatible with biological matrices and multiple clinically relevant E-AB sensor targets.
Carbon fibre based electrodes for structural batteries
Authors: Gray Rob , Barthelay Thomas , Bowen Chris R. , Marken Frank , Lunt Alexander J. G. , Asp Leif E. , Zenkert Dan , Rodriguez Paloma Santana , Xu Johanna , Bouton Karl , Rhead Andrew T.
Published: August 2024

This review captures the state-of-the-art carbon fibre-based electrodes and outlines the required research for them to deliver improvements in electrochemical and mechanical performance of structural batteries in future electrified transport.
Unveiling the structural integrity of tunnel-type Na0.44MnO2 cathode for sodium ion battery
Authors: Chakrabarty Sankalpita , Dar Javeed Ahmad , Joshi Akanksha , Paperni Arad , Taragin Sarah , Maddegalla Ananya , Sai Gautam Gopalakrishnan , Mukherjee Ayan , Noked Malachi
Published: August 2024

Tunnel-type Na0.44MnO2 (tt-NMO) is a promising cathode for sodium ion battery having excellent structural stability, diffusion kinetics, and low cost.
Colloidal photonic crystals towards biological applications
Authors: Shu Zixin , Sun Xiaoning , Xu Xinyuan , Qin Meng , Li Jianshu
Published: August 2024

Colloidal photonic crystals exhibit unique properties that make them ideal for biological applications. This perspective summarizes the primary properties, the strategies, and recent advancements for biological applications.
Designing the thermal processing of Ba(Ti0.8Zr0.2)O3–(Ba0.7Ca0.3)TiO3 thin films from an ethylene glycol-derived precursor
Authors: Konsago Sabi William , Žiberna Katarina , Ekar Jernej , Kovač Janez , Malič Barbara
Published: August 2024

Optimizing the processing conditions in the microstructure engineering of BZT–BCT thin films is key to optimizing their functional properties.
Electrogelation of PEDOT:PSS and its copolymer for bioelectronics
Authors: Slaughter Christopher , Velasco-Bosom Santiago , Tao Xudong , Ruiz-Mateos Serrano Ruben , Kissovsky Stefany , Mizuta Ryo , Mantione Daniele , Keene Scott T. , Malliaras George G. , Dominguez-Alfaro Antonio
Published: August 2024

This paper explores the combination of screen-printing and electrogelation of PEDOT:PSS, including non-solution-processable PEDOT:PSS-copolymers, to fabricate scalable and cost-effective coated devices for bioelectronic applications.
Review of energy management systems and optimization methods for hydrogen‐based hybrid building microgrids
Authors: Sarwar Fahad Ali , Hernando‐Gil Ignacio , Vechiu Ionel
Published: August 2024

Renewable energy‐based microgrids (MGs) strongly depend on the implementation of energy storage technologies to optimize their functionality. Traditionally, electrochemical batteries have been the predominant means of energy storage. However, technological advancements have led to the recognition of hydrogen as a promising solution to address the long‐term energy requirements of microgrid systems. This study conducted a comprehensive literature review aimed at analysing and synthesizing the principal optimization and control methodologies employed in hydrogen‐based microgrids within the context of building microgrid infrastructures. A comparative assessment was conducted to evaluate the merits and disadvantages of the different approaches. The optimization techniques for energy management are categorized based on their predictability, deployment feasibility, and computational complexity. In addition, the proposed ranking system facilitates an understanding of its suitability for diverse applications. This review encompasses deterministic, stochastic, and cutting‐edge methodologies, such as machine learning‐based approaches, and compares and discusses their respective merits. The key outcome of this research is the classification of various energy management strategy methodologies for hydrogen‐based MG, along with a mechanism to identify which methodologies will be suitable under what conditions. Finally, a detailed examination of the advantages and disadvantages of various strategies for controlling and optimizing hybrid microgrid systems with an emphasis on hydrogen utilization is provided.
Frequency coupling suppression and SISO modelling for VSCs with DC‐link dynamics in weak grids
Authors: Wang Zhen , Pan Hao , Cheng Peng , Jia Limin
Published: August 2024

This study proposes a frequency coupling suppression strategy for voltage source converters (VSCs) with DC‐link dynamics to address the challenges posed by the asymmetric system structures for system modelling and control design. The strategy introduces a reshaping outer loop into the q‐axis, which eliminates the conjugate voltages and currents induced by the DC‐link dynamics, to achieve decoupling of the DC‐link voltage control (DVC). Therefore, the VSC is modelled as a single‐input single‐output (SISO) admittance model, which provides clear physical insights for the analysis of admittance characteristics. Compared with the admittance matrix, the SISO model reveals the dominance of each control dynamics on VSC admittance in different frequency bands. This insight facilitates the exploration of optimized control strategies to improve the system stability margin. Based on the SISO model, a virtual admittance for compensating the negative resistive effect of the PLL is designed to illustrate the advantages of the proposed method in providing design‐oriented analysis. Experimental results verify the effectiveness of the proposed control strategy.
Advancing Patient Safety in Interventional Radiology: Effective Dose Evaluation and LDRL
Authors: M Alvarez , RAC Guassu , AA Rosa , RR Sousa , Pina DP
Published: August 2024

This study highlights the significance of radioprotection in interventional radiology, focusing on the assessment of Effective Dose values to which patients are exposed. To facilitate this, we developed a semi-automatic software employing Optical Character Recognition technology. This software analysed 1125 interventional procedures conducted between January 2021 and September 2023 at a large Brazilian hospital. The database includes the type of procedure, Air Kerma value, Kerma-Area Product, number of cineangiography images, and exposure duration, all realized on an Artis Zee® (Siemens Healthineers, Germany) C-arm. We established Local Diagnostic Reference Levels (LDRLs) and calculated Effective Dose values using the PCXMC 2.0 Monte Carlo simulation software. These calculations were based on data from the hospital and LDRLs determined in subsequent studies. The findings reveal that both the LDRLs and the calculated Effective Dose generally fall below the values reported in existing literature. This underscores the efficacy of our methodology in enhancing radioprotection and dose monitoring within the studied hemodynamics sector.
Relationship between radiation dose indices and patient size in adult brain computed tomography
Authors: Mitsui K. , Inoue Y. , Itoh H. , Hata H. , Miyatake H. , Yamane T.
Published: August 2024

The relationship between radiation dose indices and patient size was investigated in adult brain CT scans to assess the significance of considering the patient size for radiation dose management. Two hundred patients who underwent brain CT using automatic exposure control were enrolled. The radiation dose indices (volume CT dose index, CTDIvol; size-specific dose estimate, SSDE; dose length product, DLP) were compared with the head size indices (effective diameter, ED; water-equivalent diameter, WED) and body weight. The CTDIvol and SSDE correlated positively with the ED and WED. The correlations were higher for the WED than the ED and for the CTDIvol than the SSDE. Although the DLP also correlated positively with the ED and the WED, the correlations were lower than those for the CTDIvol and the SSDE. The CTDIvol and SSDE showed significant positive correlations with body weight, but the correlations were lower than those for the ED. In conclusion, the radiation dose indices in adult brain CT correlate with the head size indices. Consideration of the head size indices is recommended for radiation dose management in brain CT. The relationship between the radiation dose indices and body weight may be of some significance when the head size indices are not readily available.
Transcecal endoscopic appendectomy for management of complex appendiceal polyps extending into the appendiceal orifice
Authors: Keihanian Tara , Khalaf Mai A , Aloor Fuad Zain , Zamil Dina Hani , Jawaid Salmaan , Othman Mohamed O.
Published: August 2024

Background and study aims Endoscopic resection of appendiceal
orifice (AO) polyps extending inside the appendiceal lumen is challenging given the inability
to determine polyp lateral margins and risk of appendicitis. Transcecal endoscopic
appendectomy (TEA) ensures en bloc resection of these complex polyps.

Patients and methods This case series includes patients who
underwent TEA by a single endoscopist in the United States. Technical success was defined as
achieving complete removal of the appendix along with AO polyp in an en bloc fashion.

Results In total, nine patients were included (mean age 69.7 ±
9.6 years). The average appendix size was 4.07 ± 2.02 cm. Technical success was achieved in
100% of the patients. The average procedure length was 118.1 ± 44.21 minutes. The en bloc
resection rate, R0 resection rate, and curative resection rates were 100%. Patients were
observed for an average of 3.1 ± 1.6 days. One patient developed loculated fluid collection 9
days post procedure, which resolved on its own with oral antibiotic therapy. No other adverse
events were recorded.

Conclusions This was an early study of the feasibility of TEA in
the United States. This novel technique, in early-stage development, is potentially safe and
associated with a minimal risk profile in expert hands. Further prospective studies are needed
to standardize the technique.
PIFA-Mediated Intramolecular Dearomatization of Phenol-Tethered 1,2-Diazoles: Synthesis of Spirocyclohexadienone-pyrazolo[3,4-b]piperidinones
Authors: Natarajan Pradeep , Bachhaley Pratibha , Tripathy Sweta , Vasantharaj P Ashok , Peruncheralathan Saravanan
Published: August 2024

In recent years, the significance of spirocyclic motifs in drug discovery has increased, owing to their unique ability to engage biological targets. We present the first example of PIFA-mediated dearomative spirocyclization of phenol-tethered pyrazoles, highlighting intramolecular trapping by the pyrazole moiety. This method efficiently affords a variety of spirocyclohexadienone-pyrazolo[3,4-b]piperidinones with yields of up to 82%. Mechanistic studies reveal that the dearomatization process involves a cationic intermediate.
Exploring the translational impact of type 1 diabetes on cerebral neurovascular function through ECoG-LSCI
Authors: Yen Shaoyu , Wang Yuhling , Liao Lun-De
Published: August 2024

Type 1 diabetes mellitus (T1DM) can result in complications such as retinopathy, nephropathy, and peripheral neuropathy, which can lead to brain dysfunction. In this study, we investigated the effects of T1DM on cerebral neurovascular function in mice. Streptozotocin (STZ) is known to induce T1DM in animals; thus, we used an STZ-induced diabetes model to evaluate the effects of hyperglycemia on brain morphology and neurovascular tissue. Neurovascular coupling is the connection between neuronal activity and cerebral blood flow that maintains brain function. The ECoG-LSCI technique combines electrocorticography (ECoG) and laser speckle contrast imaging (LSCI) to detect cortical spreading depression (CSD) as a marker of neurovascular coupling and measure corresponding neurovascular function. Our results suggested that in the STZ group, hyperglycemia affected excitatory neurotransmission and metabolism, leading to reductions in intercellular signaling, somatosensory evoked potential (SSEP) amplitudes, and CSD transmission rates. Western blot data further revealed that brain-derived neurotrophic factor (BDNF) and neuronal nuclear antigen levels were reduced in the STZ group. Abnormalities in glucose metabolism in the brain and increased phosphorylation of AKT and GSK3 are hypothesized to be responsible for these decreases. Overall, this study highlights the importance of glucose metabolism in normal brain physiology and demonstrates that hyperglycemia disrupts neurovascular coupling and affects cerebral neurovascular function and that the degree of CSD is positively correlated with the extent of brain tissue damage. Further research is essential to gain a complete understanding of the related mechanisms and the implications of these findings.
Radiation in the black hole–plasma system: Propagation in equatorial plane
Authors: Balek Vladimír , Bezděková Barbora , Bičák Jiří
Published: August 2024

Effect of cold plasma on the form of rays propagating in the equatorial plane of a rotating black hole is investigated. Two kinds of regions in the radius–impact parameter plane allowed for the rays are constructed: for radiation with a given frequency at infinity and for radiation with a given “telescope frequency” seen by a local observer. The form of allowed regions for locally nonrotating observers as well as observers falling freely from infinity is established. The allowed regions contain rays which directly reach the horizon, or there exists a “neck” connecting the forbidden regions such that the rays coming from infinity cannot reach the horizon. In case we considered a set of observers at various radii instead of the neck we find two different regions – from one the rays reach the horizon and not infinity and from the other one they reach infinity, but not the horizon. The results are analyzed by analytical methods and illustrated by figures constructed numerically.
Simulation study on the influence of initial density distribution of laser ionized plasma on the ion extraction characteristics
Authors: Chen Xing , Lu Xiao-Yong , Cai Lu
Published: August 2024

In isotope concentration technology, ion extraction current and ion extraction efficiency are the key factors to measure the efficiency of the isotope concentration. In order to increase the ion extraction current, researchers usually hope to produce a plasma source with large initial peak density and width; however, in reality, it is limited by the laser power, and the total number of ions in a plasma produced by laser ionization is almost certain. In this case, how to improve the ion extraction efficiency by choosing the appropriate initial density distribution of plasma has become a difficult problem. In this paper, the effects of the initial density distribution of plasma on the ion extraction characteristics are studied by using the electron equilibrium fluid model. The numerical results suggest that the ion extraction efficiency is independent of the initial density distribution of plasma while the total number of ions in the plasma, the distance between the electrodes, and the electric field intensity are kept constant. When the total number of ions and the electric field intensity are kept constant, the distance between the electrodes is shortened by one time, and the time of ion extraction is also shortened by nearly one time; thus, the plasma source with high initial peak density and small width can be chosen, and the aim of ion extraction can be achieved by shortening the distance between the electrodes. This research results provide an important reference for guiding the experimental parameters such as laser power distribution and the design of ion extraction device.
Optimal energy scheduling for microgrid based on GAIL with Wasserstein distance
Authors: Wang Kuo , Zhang Zhanqiang , Meng Keqilao , Lei Pengbing , Wang Rui , Yang Wenlu , Lin Zhihua
Published: August 2024

Owing to the volatility and intermittency of renewable energy generation units in microgrids, effective energy scheduling methods are essential for efficient renewable energy utilization and stable microgrid operation. In recent years, microgrid energy optimization scheduling based on deep reinforcement learning (DRL) has made significant progress. With the development of the microgrid, the drawbacks of the traditional DRL agent, such as long training time and poor convergence effect, are gradually revealed. This paper proposes a generative adversarial imitation learning method with Wasserstein distance for optimal energy scheduling in the microgrid. This method combines a proximal policy optimization algorithm to optimize energy scheduling and reduce microgrid operating costs. First, the agent adaptively learns the action exploration process by imitating expert trajectories. Second, based on the generative adversarial theory, a discriminator network is added, and the Wasserstein distance is introduced into the discriminator network to distinguish between the generative and expert strategies. This feedback assists in updating the neural network parameters. Finally, the effectiveness of the proposed method is verified through an arithmetic example analysis.
A denoising method for power equipment images based on block-matching and 3D filtering
Authors: Jiang Hua , Wu Changdong
Published: August 2024

A substation is important equipment of the power system, and there are many power equipment components in the substation. In order to better detect the working status of power equipment components, it is necessary to preprocess these components. In the actual application, the power equipment images may be noisy due to external environmental interference. Therefore, it should denoise these images in order to improve system detection performance. This paper uses the acquired power equipment images and adds noise intensity of 10, 15, 20, 25, and 30, respectively. Then, the Block-Matching and 3D Filtering (BM3D) method is used to denoise these images. BM3D includes three steps such as block combination, collaborative filtering, and integration, which has strong denoising ability. The experimental results show that the proposed method outperforms other methods in terms of denoising visual effects and evaluation indicators. Especially in terms of preserving details and textures of the denoised image, there is a significant advantage in suppressing strong noise. In summary, the proposed method can achieve encouraging denoising results, which is an effective denoising method for power equipment images.
Single-mode fiber multi-level all-optical switching using GSST-graphene oxide hybrid thin film structure
Authors: Gan Soon Xin , Chew Jing Wen , Ng Kok Bin , Tey Lian Seng , Chong Wu Yi , Goh Boon Tong , Lai Choon Kong , Choi Duk-Yong , Madden Steve , Ahmad Harith
Published: August 2024

Ge2Sb2Se4Te1 (GSST) exhibits unprecedented broadband transparency over the infrared wavelength range and has emerged as a promising functional material in photonic applications that operate in the optical fiber telecommunication wavelength band. In this work, GSST and graphene oxide (GO) are integrated into an optical fiber link to achieve all-fiber non-volatile multilevel photonic memory. The GSST and GO (GSST-GO) duo-layer hybrid structure is sandwiched between two optical fiber ferrules, where the GO acts as a localized heat source to initiate the phase transition of GSST upon optical excitation. The GSST-GO-coated fiber exhibits a low insertion loss of 0.8 dB and a maximum readout contrast of about 32%, with at least five distinguished memory states. The response time of the device is measured in the range between 2.5 and 9.5 μs. This work serves as a proof of concept on implementing the GSST-GO duo-layer hybrid structure in optical fiber platform to realize all-fiber non-volatile multi-bit channel control or data storage.
Effect of driving current profile on acceleration efficiency of electromagnetic railgun
Authors: Majumder Dipjyoti Balo , Verma Rishi , Aravind J. M. V. V. S. , Rao J. N. , Meena Manraj , Rongali Lakshman Rao , Sethi Bijayalaxmi , Sharma Archana
Published: August 2024

In this paper, the effect of driving current profile on efficient utilization and conversion of stored electrical energy into kinetic energy of the projectile has been investigated for electromagnetic railgun systems. It has been experimentally evidenced and also corroborated by simulation results that the acceleration efficiency of railgun launcher is much higher for the case when the driving current feed has an over-damped unidirectional profile vs the case when an under-damped sinusoidal current of same amplitude is fed. To analyze this effect, a mathematical model has been developed incorporating dynamic resistance scaling and velocity dependent frictional effects. For the typical case of projectile weighing ∼8 g and input driving current amplitude of ∼220 kA, the estimated average force from the mathematical model simulation acting on the armature projectile increases from 1.4 to 3.83 kN, consequently resulting in an increase in velocity from 489 to 931 m/s and overall efficiency from 0.55% to 2% for the sinusoidal and unidirectional current profiles, respectively. Experimentally, a maximum velocity of ∼1024 m/s was obtained when a unidirectional over-damped current of similar amplitude was fed using a pulse shaping inductor in conjunction with a crowbar switch. The obtained experimental results of trials with different masses of armatures complement the results of the conceived mathematical model used in simulations. The marginal underestimation of the simulated velocity is due to the inevitable lacking in precise estimation of the frictional force and mass loss that dynamically occur in the projectile during acceleration.
Field emission control by work function modulation in graphene edge cathodes
Authors: Yoon Cheul Hyun , Seo Gyeong Min , Yoon Seok Hyun , Kong Byoung Don
Published: August 2024

We investigate the potential of nanovacuum devices utilizing graphene edges as field emitters, with their work function modulated by a nearby gate on the graphene surface. Unlike metals, the semi-metallic nature of graphene enables modulation of the Fermi level and work function via the surface field. This modulation alters the potential barrier for field emission. Our simulation study reveals that device operation critically depends on two screening factors—horizontal and vertical. Horizontally, work function modulation occurs when the emitter edge is within the critical screening length from the gate edge. Vertically, the effectiveness of work function modulation diminishes beyond the second layer of multi-layer graphene due to surface field screening by the first layer. Our simulations demonstrate that maintaining the vacuum channel on tens of nanometer scale enables transistor-like operation of the device, with remarkably high cut-off frequencies and maximum oscillation frequencies ranging from 0.45 to 0.71 and 32.9 to 40.5 THz, respectively, under source–drain bias from 90 to 100 V.
Hydraulic and heat transfer characteristics in corridor-shaped air-cushion surge chambers in hydropower systems
Authors: Liu Jiachun , Cheng Yongguang , Hu Jianyong , Yu Xiaodong
Published: August 2024

The large aspect ratio of a corridor-shaped air cushion surge chamber in hydropower systems results in special hydraulic and heat transfer characteristics that differ from those of cylindrical shapes. The complexities of inflow jet and outflow vortex phenomena at the throttle orifice, along with the thermal energy exchange across the water–air interface during load variations, continue to be areas of limited understanding. The hydraulic and heat transfer processes during the load variation conditions were simulated precisely using the volume of fluid model to address the above knowledge gap by adopting computational fluid dynamics. The effects of various parameters on pressure and flow patterns (including initial water depth, orifice size, aspect ratio of the surge chamber, and unit closure time) and the thermodynamic response of the air during the compression and expansion phases were analyzed. The results indicate that a smaller orifice size has larger Froude numbers, thus intensifying jet heights and exacerbating wave fluctuations. An increased initial water depth or a reduced aspect ratio of the corridor-shaped chamber decreases the angular velocity of the fluid above the orifice during load increase, thus attenuating the vortex intensity. A method for calculating the heat transfer rate in the chamber was developed by considering the heat exchanges between water, chamber wall, and air. The intense heat transfer at the water–air interface is caused by large wave fluctuations due to velocity gradients. In addition, larger orifice size increases the flow rate and heat transfer rate, leading to an increase in the total heat transfer coefficient of the chamber.
Dynamic surfactants drive anisotropic colloidal assembly
Authors: Xu Yaxin , Jandhyala Prabhat , Takatori Sho C.
Published: August 2024

Colloidal building blocks with re-configurable shapes and dynamic interactions can exhibit unusual self-assembly behaviors and pathways. In this work, we consider the phase behavior of colloids coated with surface-mobile polymer brushes that behave as “dynamic surfactants.” Unlike traditional polymer-grafted colloids, we show that colloids coated with dynamic surfactants can acquire anisotropic macroscopic assemblies, even for spherical colloids with isotropic attractive interactions. We use Brownian Dynamics simulations and dynamic density functional theory to demonstrate that time-dependent reorganization of the dynamic surfactants leads to phase diagrams with anisotropic assemblies. We observed that the microscopic polymer distributions impose unique geometric constraints between colloids that control their packing into lamellar, string, and vesicle phases. Our work may help discover versatile building blocks and provide extensive design freedom for assembly out of thermodynamic equilibrium.
Structural interspecies variability of mammals' hairs
Authors: Greco Gabriele , Rising Anna
Published: August 2024

Hairs are fundamental structures for mammals, serving crucial functions such as thermal insulation and hydrophobicity. In domestic animals, hair is also a valuable source of high-performance fibers for the textile industry, which has led to intensive study. However, there is limited comparative knowledge about the physical properties of hair across different wild mammalian species. In our lab, we are investigating the physical properties of hairs from a diverse range of wild mammalian species, laying the groundwork for an in-depth comparative study. These physical properties can be linked to the internal structures of the hairs. Using polarized light microscopy, we can visualize the internal structure of hairs, which are composed of a hollow channel (medulla) surrounded by a cortex and a keratin cuticle(1). By examining the brown hairs of three distinct mammals—the Patagonian mara, the brown bear, and the Amur tiger—we observe striking differences in their internal structures. We speculate that these structural differences correspond to varying physical properties, which we are currently investigating.
Soil capacity to biomass production in sandy loam soils following cover crop farming systems in tropical conditions in the Northeast region of Brazil
Authors: Nascimento Gislaine dos Santos , Souza Tancredo , da Silva Lucas Jónatan Rodrigues , Santos Djail
Published: August 2024

Context Soil capacity to biomass production (SC) sheds light on soil health and its capacity to sustain high primary production. However, the currently existing models are based on rather local data, and thus there is a lack of predictive tools to monitor SC. Aims Our aim was to assess the influence of cover crops on soil chemical properties by considering their different behaviours (biomass production and root density). Methods We characterised soil chemical properties, and plant biomass production during 6 years in field conditions at a tropical soil. Key results Our findings suggest that: (1) green manure practice improved Ca2+, K+, and soil organic carbon (SOC) stock, but none of the studied cover crops were able to improve soil P content; and (2) we found three groups of green manure by considering the SC reduction, namely G1 (low SC reduction) that comprises Crotalaria ochroleuca and Neonotonia wightii, G2 (medium SC reduction) that comprises Brachiaria decumbens, Pennisetum glaucum, and Crotalaria juncea, and G3 (high SC reduction) that comprises Mucuna pruriens, Canavalia ensiformis, Crotalaria spectabilis, Dolichos lablab, and Stizolobium aterrimum. Conclusion We concluded that after 3 years during which soil parameters and the production of most, but not all, cover crops have increased, the deficiency in P did not allow plants to grow well anymore. Implications This study highlights the importance to consider predictive models as a tool to be used in soil management. Our study also provides a deeper view about the use of green manure and their influence on soil capacity to biomass production.
Brushtail possums (Trichosurus vulpecula) dominate dama wallabies (Notamacropus eugenii) and Bennett’s wallabies (Notamacropus rufogriseus) at bait feeders: implications for invasive species management
Authors: Hickling Graham J. , Day Tim D.
Published: August 2024

Context Dama wallaby (Notamacropus eugenii) and Bennett’s wallaby (N. rufogriseus) are invasive pests on the New Zealand mainland and consequently are subject to ongoing control measures that include deployment of toxic baits in feeding stations. Aim We investigated whether behavioural interactions between wallabies and introduced brushtail possums (Trichosurus vulpecula) at bait feeders are likely to reduce the efficacy of this method for wallaby control. Methods Wallaby and possum visits and encounters at cereal bait feeders were monitored with trail cameras for several months in dama wallaby habitat near Rotorua, and in Bennett’s wallaby habitat in South Canterbury. The response of Bennett’s wallabies to possum carcases placed at feeders was also assessed. Key results The diurnal activity of wallabies and possums at the feeders overlapped extensively, although Bennett’s wallabies exhibited more daytime activity than the other two species. Thousands of visits by wallabies and possums were recorded but close encounters between the species at feeders were infrequent (N = 251). When encounters did occur, the wallaby was usually excluded from the feeder (72% of 229 encounters at Titoki Estate, near Rotorua, and 95% of 22 encounters at Blue Cliffs, South Canterbury) regardless of which species arrived at the feeder first. Zero instances of a wallaby excluding a possum from a feeder were recorded. When possum carcases were placed beside feeders, visitations by Bennett’s wallabies reduced significantly, by 86% during the first week when a possum carcase was present. This effect was short lived, however, because the carcase soon decayed or was scavenged by other wildlife. Conclusions Despite their smaller body size, possums are strongly behaviourally dominant over both wallaby species. Consequently, possums may empty feeders of bait before visiting wallabies have an opportunity to feed. Furthermore, interruption and exclusion of feeding wallabies by possums will increase the risk of sublethal toxic dosing and consequent bait shyness. Implications Since possums are common throughout most wallaby habitat in New Zealand, their dominance behaviour is likely to reduce the efficacy of bait feeder control of wallabies at many sites. Possum population suppression is, therefore, likely to increase the effectiveness of wallaby bait feeder programs but will be costly to achieve.