bluuebunny/crossref_metadata_2025 huggingface dataset:
Late time dynamics in SUSY saddle-dominated scrambling through higher-point OTOC
Authors: Das Rathindra Nath , Dutta Sourav , Maji Archana
Published: July 2024

In this article, we propose higher-point out-of-time-order correlators (OTOCs) as a tool to differentiate chaotic from saddle-dominated dynamics in late times. As a model, we study the scrambling dynamics in supersymmetric quantum mechanical systems. Using the eigenstate representation, we define the 2N-point OTOC using two formalisms, namely the ’Tensor Product formalism’ and the ’Partner Hamiltonian formalism’. We analytically find that the 2N-point OTOC for the supersymmetric 1D harmonic oscillator is in exact agreement with that of the 1D bosonic harmonic oscillator system. We show that the higher-point OTOC is a more sensitive measure of scrambling than the usual 4-point OTOC. To demonstrate this, we analyze a supersymmetric sextic 1D oscillator, for which the bosonic partner system has an unstable saddle in the phase space, while the saddle is absent in the fermionic counterpart. For such a system, we show that the saddle-dominated scrambling, higher anharmonic potential effects, and the supersymmetric OTOC exhibit similar dynamics due to supersymmetry constraints. Finally, we illustrate that the late-time dynamics of the higher-point OTOC become oscillatory after the peak for saddle-dominated scrambling and anharmonic oscillator systems. We propose the higher-point OTOC as a probe of late-time dynamics in non-chaotic systems that exhibit fast early-time scrambling.
Refractive index sensor based on an annular cavity and an equilateral triangular cavity for temperature detection
Authors: Yan Shubin , Wang Jin , Su Yiru , Liu Feng , Chang ShuWen , Cao Yuhao , Cui Yang , Liu Jilai , Zhang Yi , Ren Yifeng
Published: July 2024

The present study proposes a novel refractive index sensor utilizing asymmetric linear scattering frequency phenomena, which is formed by coupling a metal insulator metal (MIM) waveguide structure with an equilateral triangular ring cavity structure(ETRC). The transmission characteristics of the sensor structure were investigated using finite element method (FEM),with a focus on the effect of structure-related variables on sensing characteristics. Due to its advantages of small size, fast reaction speed, and flexibility, the designed sensor can achieve sensitivity and light efficiency values of 2880 nm RIU−1 and 50.53. In addition to this, the sensor structure can also be applied in the field of temperature detection with a sensitivity of up to 1.46 nm °C−1.
Dynamics of memristive Liu system and its DSP implementation
Authors: Tayyab Muhammad , Sun Kehui , Yao Zhao , Wang Huihai
Published: July 2024

In this paper, a novel four-dimensional memristive system is investigated to generate abundant dynamical behaviors. By combining the Liu chaotic system with an ideal memristor, an enhanced chaotic system is proposed. Dynamical analysis indicates that the new system sustains stable chaotic states and exhibits complex behaviors, with the help of the Lyapunov exponents, bifurcation diagrams, Poincaré section, parametric offset boosting, and SE complexity. The coexistence of attractors is investigated by the variation of parameters. The chaotic performance is enhanced in the proposed system, broadens the range of parameters for chaotical oscillations, and transforms periodic and quasiperiodic states into chaos. The practical applicability and feasibility of the system are validated via NIST testing and DSP implementation. The system exhibits resilient dynamical characteristics that make it highly suitable for deployment in various domains, including secure communication and signal detection.
An innovative design and metrological testing to evaluate the performance of UV phototherapy devices
Authors: Faramawy Samaa M
Published: July 2024

Narrowband UVB is the main type of light used to treat various dermatological conditions by administering appropriate doses. In this study, a new design was developed for an open-plan phototherapy device and assessed whether this could improve uniformity and deliver a higher dose, thus reducing treatment times. On the other hand, the uniformity and irradiation dose of a current model of (UV) phototherapy device were investigated. A simulation software was used to present the comparison of the simulated irradiation measurements and uniformity estimation for both the present device and the proposed device. In comparison to a present model of UV therapy device measurements, the results showed that the suggested (UV) phototherapy design device increased the irradiation dose value by 10%, improved the uniformity by 9.3%, and consequently reducing the exposure time by 13%. On the other hand, for both the current (UV) phototherapy equipment and the suggested design device, the irradiation loss value resulting from any UV lamp inefficiency was also calculated. The current model device’s loss value percentage was 15%, however, the loss value of the suggested design for the UV phototherapy device was between 3 and 4%. Based on the results discussed throughout the paper, the findings indicate that the suggested design is promising for UV phototherapy applications.
Magnetar-powered neutrinos and magnetic moment signatures at IceCube
Authors: Brdar Vedran , Cheng Ting , Kuan Hao-Jui , Li Ying-Ying
Published: July 2024

The IceCube collaboration pioneered the detection of 𝒪(PeV) neutrino events and the identification of astrophysical sources of high-energy neutrinos.
In this study, we explore scenarios in which high-energy neutrinos are produced in the vicinity of astrophysical objects with strong magnetic field, such as magnetars. While propagating through such magnetic field, neutrinos experience spin precession induced by their magnetic moments, and this impacts their helicity and flavor composition at Earth.
Considering both flavor composition of high-energy neutrinos and Glashow resonance events we find that detectable signatures may arise at neutrino telescopes, such as IceCube, for presently unconstrained neutrino magnetic moments in the range between 𝒪(10-15) μB
and 𝒪(10-12) μB
.
Casson hybrid nanofluid flow over a Riga plate for drug delivery applications with double diffusion
Authors: Alnahdi Abeer S. , Gul Taza
Published: July 2024

Casson fluid-mediated hybrid nanofluids are more effective at transferring heat than traditional heat transfer fluids in terms of thermal conductivity. Heat exchangers, cooling systems and other thermal management systems are ideal for use with Casson fluids. Precise control of the flow and release of medication is necessary when using Casson fluids in drug delivery systems because of their unique rheological properties. Nanotechnology involves the creation of nanoparticles that are loaded with drugs and distributed in Casson fluid-based carriers for targeted delivery. In this study, to create a hybrid nanofluid, both single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs) are dispersed in a Casson fluid with Fourier’s and Fick’s laws assumptions. The Casson fluid is suitable for various engineering and medical applications due to the enhancement of heat transfer and thermal conductivity by the carbon nanotubes. Our objective is to understand how SWCNTs and MWCNTs impact the flow field by studying the flow behavior of the Casson hybrid nanofluid when it is stretched against a Riga plate. The Darcy–Forchheimer model is also used to account for the impact of the porous medium near the stretching plate. Both linear and quadratic drag terms are taken into account in this model to accurately predict the flow behavior of the nanofluid. In addition, the homotopy analysis method is utilized to address the model problem. The outcomes are discussed and deliberated based on drug delivery applications. These findings shed valuable light on the flow characteristics of a Casson hybrid nanofluid comprising SWCNTs and MWCNTs. It is observed that the incorporation of carbon nanotubes makes the nanofluid a promising candidate for medical applications due to its improved heat transfer properties.
Effect of matrix thermal properties on laser-induced plasma
Authors: Shan 单 Yuheng 宇恒 , Li 李 An 安 , Zhang 张 Xinyu 新宇 , Yi 易 Wen 文 , Zhang 张 Ying 颖 , Liu 刘 Xiaodong 晓东 , Liu 刘 Ruibin 瑞斌
Published: July 2024

The matrix thermal properties have an important impact on laser-induced plasma, as the thermal effect dominates the interaction between ns-pulsed laser and matter, especially in metals. We used a series of pure metals and aluminum alloys to measure plasma temperature and electron density through laser-induced breakdown spectroscopy, in order to investigate the effect of matrix thermal properties on laser-induced plasma. In pure metals, a significant negative linear correlation was observed between the matrix thermal storage coefficient and plasma temperature, while a weak correlation was observed with electron density. The results indicate that metals with low thermal conductivity or specific heat capacity require less laser energy for thermal diffusion or melting and evaporation, resulting in higher ablation rates and higher plasma temperatures. However, considering ionization energy, thermal effects may be a secondary factor affecting electron density. The experiment of aluminum alloy further confirms the influence of thermal conductivity on plasma temperature and its mechanism explanation.
Delayed-measurement one-way quantum computing on cloud quantum computer
Authors: Yang 杨 Zhi-Peng 智鹏 , Zhang 张 Yu-Ran 煜然 , Li 李 Fu-Li 福利 , Fan 范 Heng 桁
Published: July 2024

One-way quantum computation focuses on initially generating an entangled cluster state followed by a sequence of measurements with classical communication of their individual outcomes. Recently, a delayed-measurement approach has been applied to replace classical communication of individual measurement outcomes. In this work, by considering the delayed-measurement approach, we demonstrate a modified one-way CNOT gate using the on-cloud superconducting quantum computing platform: Quafu. The modified protocol for one-way quantum computing requires only three qubits rather than the four used in the standard protocol. Since this modified cluster state decreases the number of physical qubits required to implement one-way computation, both the scalability and complexity of the computing process are improved. Compared to previous work, this modified one-way CNOT gate is superior to the standard one in both fidelity and resource requirements. We have also numerically compared the behavior of standard and modified methods in large-scale one-way quantum computing. Our results suggest that in a noisy intermediate-scale quantum (NISQ) era, the modified method shows a significant advantage for one-way quantum computation.
Memristors-coupled neuron models with multiple firing patterns and homogeneous and heterogeneous multistability
Authors: Wang 王 Xuan 暄 , Banerjee Santo , Cao 曹 Yinghong 颖鸿 , Mou 牟 Jun 俊
Published: July 2024

Memristors are extensively used to estimate the external electromagnetic stimulation and synapses for neurons. In this paper, two distinct scenarios, i.e., an ideal memristor serves as external electromagnetic stimulation and a locally active memristor serves as a synapse, are formulated to investigate the impact of a memristor on a two-dimensional Hindmarsh–Rose neuron model. Numerical simulations show that the neuronal models in different scenarios have multiple burst firing patterns. The introduction of the memristor makes the neuronal model exhibit complex dynamical behaviors. Finally, the simulation circuit and DSP hardware implementation results validate the physical mechanism, as well as the reliability of the biological neuron model.
Accelerator beam phase space tomography using machine learning to account for variations in beamline components
Authors: Wolski A. , Botelho D. , Dunning D. , Pollard A.E.
Published: July 2024

We describe a technique for reconstruction of the
four-dimensional transverse phase space of a beam in an accelerator
beamline, taking into account the presence of unknown errors on the
strengths of magnets used in the data collection. Use of machine
learning allows rapid reconstruction of the phase-space distribution
while at the same time providing estimates of the magnet errors. The
technique is demonstrated using experimental data from CLARA, an
accelerator test facility at Daresbury Laboratory.
Winter climate preconditioning of summer vegetation extremes in the Northern Hemisphere
Authors: Anand Mohit , Hamed Raed , Linscheid Nora , Silva Patrícia S , Andre Julie , Zscheischler Jakob , Garry Freya K , Bastos Ana
Published: July 2024

The impact of the spring climate on the Northern Hemisphere’s summer vegetation activity and extremes has been extensively researched, but less attention has been devoted to whether and how the winter climate may additionally influence vegetation extremes in the summer. Here, we provide insights into the influence of winter temperature and precipitation on summer vegetation extremes in the Northern Hemisphere. To do this, we identify positive and negative extremes in the summer leaf area index (LAI, a proxy for vegetation activity) and assess winter effects on those extremes using logistic regression at the regional scale. Over a quarter of the regions in the Northern Hemisphere show strong winter climate preconditioning on summer LAI extremes, which is typically stronger for croplands than forests. In regions with strong winter preconditioning, the spring LAI mediates the link between winter climate and summer LAI extremes through the ecological memory in seasonal legacy effects. Our findings suggest that extremely low summer LAI in both croplands and forests is preconditioned by colder and drier winters, while extremely high summer LAI in forests is associated with warmer and wetter winters. For low summer LAI in croplands, warmer winters are associated with an increased likelihood of extremes in mid-latitude regions and a reduced likelihood in high-latitude regions. Consideration of winter preconditioning effects may improve our understanding of inter-annual variability of vegetation activity and support agricultural and land management practitioners in anticipating the detrimental effects of winter on crop yields and forest conditions.
Riboflavin overproduction from diverse feedstocks with engineered Corynebacterium glutamicum
Authors: Pérez-García Fernando , Brito Luciana Fernandes , Bakken Thea Isabel , Brautaset Trygve
Published: July 2024

Riboflavin overproduction by Corynebacterium glutamicum was achieved by screening synthetic operons, enabling fine-tuned expression of the riboflavin biosynthetic genes ribGCAH. The synthetic operons were designed by means of predicted translational initiation rates of each open reading frame, with the best-performing selection enabling riboflavin overproduction without negatively affecting cell growth. Overexpression of the fructose-1,6-bisphosphatase (fbp) and 5-phosphoribosyl 1-pyrophosphate aminotransferase (purF) encoding genes was then done to redirect the metabolic flux towards the riboflavin precursors. The resulting strain produced 8.3 g l−1 of riboflavin in glucose-based fed-batch fermentations, which is the highest reported riboflavin titer with C. glutamicum. Further genetic engineering enabled both xylose and mannitol utilization by C. glutamicum, and we demonstrated riboflavin overproduction with the xylose-rich feedstocks rice husk hydrolysate and spent sulfite liquor, and the mannitol-rich feedstock brown seaweed hydrolysate. Remarkably, rice husk hydrolysate provided 30% higher riboflavin yields compared to glucose in the bioreactors.
Embedded three-dimensional printing of thick pea-protein-enriched constructs for large, customized structured cell-based meat production
Authors: Ianovici Iris , Zagury Yedidya , Afik Noa , Hendel Moran , Lavon Neta , Levenberg Shulamit
Published: July 2024

Recent 3D-printing research showed the potential of using plant-protein-enriched inks to fabricate cultivated meat (CM) via agar-based support baths. However, for fabricating large, customized, structured, thick cellular constructs and further cultivation, improved 3D-printing capabilities and diffusion limit circumvention are warranted. The presented study harnesses advanced printing and thick tissue engineering concepts for such purpose. By improving bath composition and altering printing design and execution, large-scale, marbled, 0.5-cm-thick rib-eye shaped constructs were obtained. The constructs featured stable fibrous architectures comparable to those of structured-meat products. Customized multi-cellular constructs with distinct regions were produced as well. Furthermore, sustainable 1-cm-thick cellular constructs were carefully designed and produced, which successfully maintained cell viability and activity for 3 weeks, through the combined effects of void-incorporation and dynamic culturing. As large, geometrically complex construct fabrication suitable for long-term cellular cultivation was demonstrated, these findings hold great promise for advancing structured CM research.
Development of machine learning regression models for the prediction of tensile strength of friction stir processed AA8090/SiC surface composites
Authors: Adiga Karthik , Herbert Mervin A , Rao Shrikantha S , Shettigar Arun Kumar , Shrivathsa TV
Published: July 2024

Friction Stir Processing is a state-of-the-art technology for microstructure refinement, material property enhancement, and fabrication of surface composites. Machine learning approaches have garnered significant interest as prospective models for modeling various production systems. The present work aims to develop four machine learning models, namely linear regression, support vector regression, artificial neural network and extreme gradient boosting to predict the influence of FSP parameters such as tool rotational speed, tool traverse speed and groove width on ultimate tensile strength of friction stir processed AA8090/SiC surface composites. These models were developed through Python programming and the original dataset was divided into 80% for the training phase and 20% for the testing phase. The performance of the models was evaluated by root mean squared error, mean absolute error and R2. Based on the results and graphical visualization, it was observed that the XGBoost model outperformed other models with high accuracy in predicting UTS of AA8090/SiC surface composites.
A study on the effects of hybrid (SIC- PSSA) nano sized reinforcement on mechanical and tribological behaviour of Al alloy-based metal matrix composite produced by ultrasonic assisted stir casting
Authors: Tenali Nagaraju , Ganesan G , Ravindra Babu P
Published: July 2024

This study focuses on the effects of hybrid reinforcement consisting of nanosized particles of Palm Sprout Shell Ash (PSSA) and silicon carbide (SiC) on the mechanical and tribological properties of the Al-Cu-Mg alloy. Hybrid reinforced composites with different weight percentages of SiC and PSSA (0:0, 0:4, 1:3, 2:2, and 4:0 wt%) were prepared using the ultrasonic-assisted bottom-poured stir casting technique. Scanning electron microscopy (SEM) and energy-dispersive x-ray spectroscopy (EDS) were used to characterize the hybrid composite made of Al-Cu-Mg alloy. The optical and SEM microstructural analyses demonstrated an even distribution of SiC and PSSA nano size reinforcements within the matrix. The EDS analysis revealed SiC and PSSA reinforcement particles in the composite. The mechanical properties (tensile, flexural, and impact strength) and wear properties (wear rate and coefficient of friction) of the composites and alloys were evaluated according to the ASTM standards. The hybrid reinforced composites outperformed the base alloy. Among all composites, the 2:2 wt% SIC and PSSA hybrid reinforced composites exhibited a significant enhancement in both tensile and flexural strength, with a 29.15% and 27.64% increase in strength, respectively. However, the inclusion of these reinforcements led to a reduction in the ductility and impact strength of the Al-Cu-Mg alloy composite. The 0:4 wt% SiC- and PSSA-reinforced composites experienced the largest reductions in ductility and impact strength, with decreases of 47.67% and 3.56%, respectively. For the 2:2 wt% SiC and PSSA composites, these reductions were 23.64% and 3.16%, respectively. The SEM analysis of the fractured surfaces of the composites tested for mechanical properties revealed evidence of both ductile and brittle fracture mechanisms in the tensile, flexural, and impact tests. The wear behaviour of the prepared samples was evaluated, and all composites exhibited superior performance compared with the base alloy, demonstrating adhesive and abrasive wear mechanisms and varying friction coefficients. Among all the composites, the 2:2 wt% SiC- and PSSA-reinforced composites exhibited high wear resistance and a lower coefficient of friction than the other fabricated composites.
Investigating the occurrence and predictability of pitch angle scattering events at ADITYA-Upgrade tokamak with the electron cyclotron emission radiometer
Authors: SIJU Varsha , PANDYA Santosh P. , PATHAK S. K. , PATEL Ansh , NAGORA Umesh , PUROHIT Shishir , JHA Sameer , GUPTA M. K. , TAHILIANI K. , KUMAR R. , TANNA R. L. , GHOSH J.
Published: July 2024

This paper describes the experimental analysis and preliminary investigation of the predictability of pitch angle scattering (PAS) events through the electron cyclotron emission (ECE) radiometer signals at the ADITYA-Upgrade (ADITYA-U) tokamak. For low-density discharges at ADITYA-U, a sudden abnormal rise is observed in the ECE signature while other plasma parameters are unchanged. Investigations are done to understand this abrupt rise that is expected to occur due to PAS. The rise time is as fast as 100 μs with a single step and/or multiple step rise in ECE radiometer measurements. This event is known to limit the on-axis energy of runaway electrons. Being a repetitive event, the conditions of its repetitive occurrence can be investigated, thereby exploring the possibility of it being triggered and surveyed as an alternate runaway electron mitigation plan. Functional parameterization of such events with other discharge parameters is obtained and the possibility to trigger these events is discussed. PREDICT code is used to investigate the possible interpretations for the PAS occurrence through modeling and supporting the ECE observations. The trigger values so obtained experimentally are set as input criteria for PAS occurrence. Preliminary modeling investigations provide reliable consistency with the findings.
Emergence of noise-induced barren plateaus in arbitrary layered noise models
Authors: Schumann M , Wilhelm F K , Ciani A
Published: July 2024

In variational quantum algorithms the parameters of a parameterized quantum circuit are optimized in order to minimize a cost function that encodes the solution of the problem. The barren plateau phenomenon manifests as an exponentially vanishing dependence of the cost function with respect to the variational parameters, and thus hampers the optimization process. We discuss how, and in which sense, the phenomenon of noise-induced barren plateaus emerges in parameterized quantum circuits with a layered noise model. Previous results have shown the existence of noise-induced barren plateaus in the presence of local Pauli noise (Wang et al 2021 Nat. Commun.
12 6961). We extend these results analytically to arbitrary completely-positive trace preserving maps in two cases: (1) when a parameter-shift rule holds, (2) when the parameterized quantum circuit at each layer forms a unitary 2-design. The second example shows how highly expressive unitaries give rise not only to standard barren plateaus (McClean et al 2018 Nat. Commun.
9 4812), but also to noise-induced ones. In the second part of the paper, we study numerically the emergence of noise-induced barren plateaus in QAOA circuits focusing on the case of MaxCut problems on d-regular graphs and amplitude damping noise.
An experiment on using activated carbon to remove direct dyes from wastewater collected from the textile dyeing industry
Authors: Enad Huda Yousif
Published: July 2024

Environmentalists have been raising concerns about the concentration of dye in wastewater. A wide range of industries are the major contributors to increasing the percentage of dyes in wastewater, such as the food, paper, fabric, makeup, and textile sectors. This is really posing an issue for many organisms living in water. A range of biological, physical, and chemical techniques have been developed to eliminate dye from wastewater. Different treatment techniques are well known for their efficiency in colour removal since different industries utilise different dyes. Adsorption, filtering, and coagulation/flocculation are well-known methods for physical treatment. For biological treatment, the use of microbes and enzymes, in addition to biosorption and biodegradation, is well known for its efficiency. Furthermore, the chemical treatment used ozonation, photocatalysis, and electron transport. This research used an experimental method to test the efficiency of activated carbon (AC) created from sawdust as a dye remover from wastewater. Sawdust AC was chemically and physically treated, and it was characterised by XRD, BET, SEM, FTIR, and EDX, which revealed a significant up-taking capacity that reached 73% of direct blue, green, and orange dye from its surface. It was discovered that pH values of 3 and below are optimal for the adsorption of direct dyes onto sawdust carbon. The findings suggest that sawdust carbon might be used to remove colours from wastewater at a lower cost than commercial activated carbon.
A method: multi-scale calculation life of welded beams with residual stress
Authors: Shining Lyu , Wang Aihong , Gao Youshan , Wu Huijuan , Gao Ling
Published: July 2024

To improve the accuracy of the probability of life value calculation while ensuring computational efficiency, a study was conducted on the finite element probability of life calculation method for beam-shell coupling. On the basis of the finite element heat and stress coupling model of Type I welded beam, a fatigue fracture model of residual stress and cyclic load coupling was established. The probability of life calculation of beam-shell elements was theoretically derived, and the expression of the probability of life model was unified. The probability of life of Type I welded beam was calculated, and it was compared with the model of beam assumption and the full life test result. The results show that the computational efficiency of the beam-shell coupling model is higher than that of the shell element model. In addition, the probability of life calculation result obtained by the beam-shell coupling model is highly consistent with the experimental result in statistical terms, and it has higher accuracy at low stress levels than the calculation result of the beam element, with the relative error between the median of the calculation result and the experimental result being less than 10%.
Mobility and Temperature Sensitive Energy Efficient Routing (MTS-EER) protocol in a wireless body area network
Authors: Rawat Anil K , Singh Amandeep , Singh Manwinder
Published: July 2024

Sensor technology advancements have provided the platform to implement wireless body area networks, thanks to the nanosized sensor units capable of sensing, aggregating, and forwarding physiological information. The collected information is routed to the desired destination unit for data analysis and decision-making in remote healthcare. However, improving energy utilization remains a brain-teasing problem for the research community, especially considering imbalanced energy consumption and postural movements. Mobility contributes to disconnectivity issues, high energy drainage, and retransmission delays. In addition, the sensor node’s thermal level also poses a challenge in maintaining safer and reliable data transmission. To overcome these issues, a novel Mobility and Temperature Sensitive Energy-Efficient Routing ¬(MTS-EER) algorithm has been proposed that includes a two-step process. In step 1, an Intelligent Path Estimation Function (IPEF) is designed considering the sensor’s mobility, temperature, and energy level. IPEF depends on crucial parameters i.e.: - residual energy, signal-to-noise ratio (SNR), distance, total energy, and most importantly temperature of the sensor unit. The sensor node with the least IPEF is selected as the Cluster Head (CH). In step 2, an optimized and sustainable energy conservation model (OSECM) is implemented based on the Adaptive Transmission Power (ATP) and the Power Management Module (PMM). The ATP conserves the energy via intelligently varying the transmission power and PMM manages the sleep pattern of sensor nodes to yield a high network lifetime and efficient energy utilization. The algorithm includes a clustering approach with dual sink nodes to conserve energy and improve reliability. Finally, the results are compared with the recent state-of-the-art research work. The proposed algorithm provides better results considering residual energy, throughput, network lifetime, and end-to-end delay.
Theoretical and experiment optimization research of a frequency up-converted piezoelectric energy harvester based on impact and magnetic force
Authors: Cheng Qianju , Wang Qingmeng , Liu Zhi , Lv Zean
Published: July 2024

Harvesting environmental vibrations to power electronic components is an essential approach for addressing the power supply challenge in MEMS. However, conventional vibration energy harvesting systems frequently suffer from limited frequency bandwidth and high-frequency deficiencies. This paper proposes a novel up-frequency structure for piezoelectric vibration energy harvesting (VEH) that relies on both nonlinear magnetic force and piecewise linear force. The proposed VEH’s nonlinear dynamic characteristics are analyzed theoretically, and an experimental prototype machining and vibration test platform are constructed. Theoretical and experimental results are compared and analyzed by conducting basic experiments and key parameter optimization experiments. The research results demonstrate that the proposed VEH can efficiently harvest vibration energy in low-frequency and wide-band environments. Regarding the system parameters, higher vibration acceleration results in increased output voltage and wider working frequency bandwidth. Reducing the gap distance enhances piecewise linear vibration, which broadens the working frequency bandwidth. Furthermore, the proposed VEH’s ability to harvest low-frequency vibrations can be enhanced by reducing the magnet distance, thereby reducing the linear resonance frequency of the system. The findings of this study offer valuable insights for advancing the engineering application of MEMS self-power supply technology.
Twisted logarithmic complexes of positively weighted homogeneous divisors
Authors: Bath Daniel , Saito Morihiko
Published: July 2024

For a rank 1 local system on the complement of a reduced divisor on a complex manifold

X
X

, its cohomology is calculated by the twisted meromorphic de Rham complex. Assuming the divisor is everywhere positively weighted homogeneous, we study necessary or sufficient conditions for a quasi-isomorphism from its twisted logarithmic subcomplex, called the logarithmic comparison theorem (LCT), by using a stronger version in terms of the associated complex of

D
X

D_X

-modules. In case the connection is a pullback by a defining function

f
f

of the divisor and the residue is

α
\alpha

, we prove among others that if LCT holds, the annihilator of

f

α
−
1

f^{\alpha -1}

in

D
X

D_X

is generated by first order differential operators and

α
−
1
−
j

\alpha -1-j

is not a root of the Bernstein-Sato polynomial for any positive integer

j
j

. The converse holds assuming either of the two conditions in case the associated complex of

D
X

D_X

-modules is acyclic except for the top degree. In the case where the local system is constant, the divisor is defined by a homogeneous polynomial, and the associated projective hypersurface has only weighted homogeneous isolated singularities, we show that LCT is equivalent to that

−
1

-1

is the unique integral root of the Bernstein-Sato polynomial. We also give a simple proof of LCT in the hyperplane arrangement case under appropriate assumptions on residues, which is an immediate corollary of higher cohomology vanishing associated with Castelnuovo-Mumford regularity. Here the zero-extension case is also treated.
Out-of-hospital paramedic interactions with people living with dementia: a scoping review
Authors: Han Ming Xuan , Ross Linda , Hemingway Liam , Anderson David , Gosling Cameron
Published: July 2024

Background

Dementia encompasses neurodegenerative disorders that account for a global estimated healthcare expenditure of 1.3 trillion US dollars. In Australia, one in 12 people aged ≥65 has a diagnosis of dementia and it is the second leading cause of death. Paramedics play a crucial role in person-centred dementia care, particularly in the community. While consensus has been established on paramedicine’s integration into interdisciplinary care teams, there remains a lack of clarity regarding the paramedic role in dementia care.

Objective

This study aimed to examine and report paramedic interactions with people living with dementia in the out-of-hospital setting.

Design and Setting

This was a scoping review study of paramedics and people living with dementia within the out-of-hospital setting.

Methods

This study was guided by the Joanna Briggs Institute (JBI) scoping review framework. Databases were searched without date limits, up to 4 April 2023. These encompassed OVID Medline, CINAHL, Scopus, APA PsycInfo and OVID Embase. Articles were included if they were primary, peer-reviewed studies in English and reporting on paramedic-specific interactions with people living with dementia in the out-of-hospital setting. Data extraction was performed based on study setting, design, population and key findings.

Results

Twenty-nine articles were included in the thematic analysis. Four themes emerged: need for training, patterns of attendances, patterns of documentation and the integrative potential of paramedicine. Paramedics reported feeling ill-equipped and unprepared in caring for patients living with dementia due to challenges in assessment and management of caregiver tensions. They were often called as a last resort due to poor service integration and a lack of alternative care pathways. Despite high conveyance rates, there was low incidence of paramedic interventions initiated. Underdocumentation of dementia and pain was found.

Conclusion

Emergency ambulance conveyance of people living with dementia is a surface reaction compounded by a lack of direction for paramedics in the provision of out-of-hospital care. There is a pressing need for establishment of research and educational priorities to improve paramedic training in dementia-specific skillsets.
The effect of youth-friendly health services on risk of pregnancy among adolescent girls and young women in Lilongwe, Malawi: a secondary analysis of the Girl Power–Malawi study
Authors: Graybill Lauren A , Westreich Daniel , Maseko Bertha , Phanga Twambilile , Nthani Tiyamike , Vansia Dhrutika , Chi Benjamin H , Daniels Julie L , Tang Jennifer H , Bekker Linda-Gail , Pettifor Audrey E , Rosenberg Nora E
Published: July 2024

In Sub-Saharan Africa, adolescent girls and young women aged 15 to 24 (AGYW) experience a high risk of early and unintended pregnancy. We assessed the impact of youth-friendly health services (YFHS) on pregnancy risk among AGYW who participated in the Girl Power study. In 2016, Girl Power randomly assigned 4 government-run health centers in Lilongwe, Malawi, to provide a standard (n = 1) or youth-friendly (n = 3) model of service delivery. At 6 and 12 months, study participants (n = 250 at each health center) self-reported their current pregnancy status and received a urine pregnancy test. Because of missing pregnancy test results, we used multiple imputation to correct for outcome misclassification in self-reported pregnancy status and applied the parametric g-formula on the corrected data to estimate the effect of YFHS on the 12-month risk of pregnancy. After correcting for outcome misclassification, the risk of pregnancy under the scenario where all health centers offered YFHS was 15.8% compared to 23.2% under the scenario where all health centers offered standard of care (risk difference: –7.3%; 95% CI, –15.5% to 0.8%). Access to a model of YFHS that integrates provider training with youth-friendly clinic modifications and community outreach activities may decrease risk of pregnancy among AGYW relative to standard of care.
Patient Experiences With Blood Pressure Measurement Methods for Hypertension Diagnosis: Qualitative Findings From the BP-CHECK Study
Authors: Hansell Laurel D , Hsu Clarissa W , Munson Sean A , Margolis Karen L , Thompson Matthew J , Ehrlich Kelly J , Hall Yoshio N , Anderson Melissa L , Evers Sarah C , Marcus-Smith Miriam S , McClure Jennifer B , Green Beverly B
Published: July 2024

BACKGROUND

Out-of-office blood pressure (BP) measurement is recommended when making a new hypertension diagnosis. In practice, however, hypertension is primarily diagnosed using clinic BP. The study objective was to understand patient attitudes about accuracy and patient-centeredness regarding hypertension diagnostic methods.

METHODS

Qualitative study within a randomized controlled diagnostic study conducted between May 2017 and March 2019 comparing the accuracy and acceptability of BP measurement methods among patients in an integrated healthcare delivery system. All participants completed 24-hour ambulatory blood pressure monitoring (ABPM), plus either clinic BP, home BP monitoring (HBPM), or kiosk BP diagnostic testing. Qualitative interviewees (aged 31–76 years, n = 35) were recruited from the main study.

RESULTS

Participants who completed HBPM found it to be comfortable and low burden, and believed it produced accurate results. Participants in the clinic arm described clinic measurements as inconvenient. Participants in the kiosk arm overall did not favor kiosks due to concerns about accuracy and privacy. Participants described ABPM as the most accurate method due to repeated measurements over the 24-hour period in real-world contexts, but many found it uncomfortable and disruptive. Participants also noted methods that involved repeated measures such as HBPM and ABPM particularly influenced their understanding of whether or not they had hypertension.

CONCLUSIONS

Hypertension diagnostic methods that include more BP measurements help patients gain a deeper understanding of BP variability and the lower reliability of infrequent measurements in the clinic. These findings warrant implementing strategies to enhance out-of-office BP diagnostic testing in primary care.

CLINICAL TRIALS REGISTRATION

Trial number NCT03130257.
The Utility of a Novel Neuropsychological Measurement to Analyze Event-Related Attentional Behaviors among Young Children with Attention Deficit Hyperactivity Disorder—a Pilot Study
Authors: Chen I-Chun , Zheng Yu-Qi , Zhao Hui-Xuan , Lin Li-Chen , Chen Yun-Ju , Chang Meng-Han , Ko Li-Wei
Published: July 2024

Objective

The identification and diagnosis of children with attention deficit hyperactivity disorder (ADHD) traits is challenging during the preschool stage. Neuropsychological measures may be useful in early assessments. Furthermore, analysis of event-related behavior appears to be an unmet need for clinical treatment planning. Conners’ Kiddie Continuous Performance Test (K-CPT) is the most popular well-established neuropsychological measurement but lacks event markers to clarify the heterogeneous behaviors among children. This study utilized a novel commercially available neuropsychological measure, the ΣCOG, which was more game-like and provided definite event markers of individual trial in the test.

Methods

Thirty-three older preschool children (14 were diagnosed with ADHD, mean age: 66.21 ± 5.48 months; 19 demonstrated typical development, mean age: 61.16 ± 8.11 months) were enrolled and underwent comprehensive medical and developmental evaluations. All participants underwent 2 versions of neuropsychological measures, including the K-CPT, Second Edition (K-CPT 2) and the ΣCOG, within a short interval.

Results

The study indicated the omissions and response time scores measured in this novel system correlated with clinical measurement of the behavioral scales in all participants and in the group with ADHD; additionally, associations with the traditional K-CPT 2 were observed in commissions and response time scores. Furthermore, this system provided a within-task behavioral analysis that identified the group differences in the specific trial regarding omission and commission errors.

Conclusions

This innovative system is clinically feasible and can be further used as an alternative to the K-CPT 2 especially in research by revealing within-task event-related information analysis.
Evaluation of quercetin as a potential cytoprotector against acetaldehyde using the cultured hepatocyte model with aldehyde dehydrogenase isozyme deficiency
Authors: Xu Yuhang , Sawamoto Takeshi , Sun Ruitong , Ishikura Aki , Munemasa Shintaro , Murata Yoshiyuki , Satoh Ayano , Matsumoto Akiko , Nakamura Toshiyuki , Nakamura Yoshimasa
Published: July 2024

Protective effect of quercetin against acetaldehyde was evaluated using the cultured hepatocyte models with aldehyde dehydrogenase (ALDH) isozyme deficiency (aldh2-kd and aldh1a1-kd). The quercetin-induced cytoprotection against acetaldehyde in the ALDH1A1-deficient mutant (aldh1a1-kd) was weaker than that in the wild type. Furthermore, quercetin did not enhance the ALDH activity in aldh1a1-kd cells, suggesting that ALDH1A1 is involved in quercetin-induced cytoprotection.
ScyNet: Visualizing interactions in community metabolic models
Authors: Predl Michael , Gandolf Kilian , Hofer Michael , Rattei Thomas
Published: July 2024

Motivation

Genome-scale community metabolic models are used to gain mechanistic insights into interactions between community members. However, existing tools for visualizing metabolic models only cater to the needs of single organism models.

Results

ScyNet is a Cytoscape app for visualizing community metabolic models, generating networks with reduced complexity by focusing on interactions between community members. ScyNet can incorporate the state of a metabolic model via fluxes or flux ranges, which is shown in a previously published simplified cystic fibrosis airway community model.

Availability and implementation

ScyNet is freely available under an MIT licence and can be retrieved via the Cytoscape App Store (apps.cytoscape.org/apps/scynet). The source code is available at Github (github.com/univieCUBE/ScyNet).
A curated rotamer library for common post-translational modifications of proteins
Authors: Zhang Oufan , Naik Shubhankar A , Liu Zi Hao , Forman-Kay Julie , Head-Gordon Teresa
Published: July 2024

Motivation

Sidechain rotamer libraries of the common amino acids of a protein are useful for folded protein structure determination and for generating ensembles of intrinsically disordered proteins (IDPs). However, much of protein function is modulated beyond the translated sequence through the introduction of post-translational modifications (PTMs).

Results

In this work, we have provided a curated set of side chain rotamers for the most common PTMs derived from the RCSB PDB database, including phosphorylated, methylated, and acetylated sidechains. Our rotamer libraries improve upon existing methods such as SIDEpro, Rosetta, and AlphaFold3 in predicting the experimental structures for PTMs in folded proteins. In addition, we showcase our PTM libraries in full use by generating ensembles with the Monte Carlo Side Chain Entropy (MCSCE) for folded proteins, and combining MCSCE with the Local Disordered Region Sampling algorithms within IDPConformerGenerator for proteins with intrinsically disordered regions.

Availability and implementation

The codes for dihedral angle computations and library creation are available at https://github.com/THGLab/ptm_sc.git.
Parallel phenotypic evolution of two independent cavefish lineages of Astyanax mexicanus (De Filippi, 1854) (Characiformes: Characidae)
Authors: Hernández-Lozano Jorge , Garita-Alvarado Carlos A , Munguía-Steyer Roberto , Garduño-Sánchez Marco A , Ornelas-García Claudia Patricia
Published: July 2024

Astyanax mexicanus offers a unique model for studying parallel evolution, with cave-dwelling forms arising from at least two distinct surface lineages. Here, we examined repeated evolution in the two cave-adapted lineages across four phenotypic datasets: (i) meristic data; (ii) ecomorphological data; and geometric morphometric data for (iii) head and (iv) premaxillary bone shape. Additionally, we assessed the association of these phenotypes with their phylogenetic history. Certain traits exhibited evidence of parallel evolution for the cave ecotype across lineages, such as increased maxillary tooth count, reduced lateral line scale count, and shorter ascending process of the premaxillary bone. Geometric morphometric data showed a phenotypic divergence gradient in head shape between cave and surface populations, with the strongest divergence between Sierra de El Abra and surface populations and with less differentiation between surface populations and caves from Sierra de Guatemala and Micos. Cave populations that hybridize with surface populations (e.g. Micos) displayed the greatest overlap with the surface ecotype. There was a similar divergence gradient for premaxillary bone shape, but with weaker differentiation between cave and surface ecotypes. This evidence of repeated evolution in several cave traits emphasizes the significance of selective pressures exerted by the environment on the evolution of cave ecotypes.
Absolute risk from double nested case-control designs: cause-specific proportional hazards models with and without augmented estimating equations
Authors: Lee Minjung , Gail Mitchell H
Published: July 2024

We estimate relative hazards and absolute risks (or cumulative incidence or crude risk) under cause-specific proportional hazards models for competing risks from double nested case-control (DNCC) data. In the DNCC design, controls are time-matched not only to cases from the cause of primary interest, but also to cases from competing risks (the phase-two sample). Complete covariate data are available in the phase-two sample, but other cohort members only have information on survival outcomes and some covariates. Design-weighted estimators use inverse sampling probabilities computed from Samuelsen-type calculations for DNCC. To take advantage of additional information available on all cohort members, we augment the estimating equations with a term that is unbiased for zero but improves the efficiency of estimates from the cause-specific proportional hazards model. We establish the asymptotic properties of the proposed estimators, including the estimator of absolute risk, and derive consistent variance estimators. We show that augmented design-weighted estimators are more efficient than design-weighted estimators. Through simulations, we show that the proposed asymptotic methods yield nominal operating characteristics in practical sample sizes. We illustrate the methods using prostate cancer mortality data from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial Study of the National Cancer Institute.