bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental investigations of dominant unsteady surface pressure in the corner separation region of a high-subsonic compressor cascade
Authors: Li Ruiyu , Gao Limin , Lin Shiyan , Ge Ning
Published: January 2024

The wall pressure fluctuations on compressor blades, referred to as unsteady surface pressure (USP), significantly impact vibration, noise, and aerodynamic performance. A comprehensive understanding of USP in the corner separation region can provide guidance for performance improvement of a compressor based on the mechanism analysis. However, due to the high Reynolds number of the flow, narrow space, thin blade walls, and large geometric deflection angles, obtaining the USP with a corner separation phenomenon in a high-subsonic compressor either experimentally or by numerical simulations is challenging. The aim of this work is to experimentally investigate the dynamic characteristics of the unsteady surface pressure in a high-subsonic compressor cascade suffering from a large-scale corner separation. The USP of the point-matrix on the measured surface is measured using the non-embedded measurement (NEM) method. The frequency features and dominant fluctuation areas on the blade suction and end wall surfaces within the Strouhal numbers range from 0.326 to 2.285, corresponding to the frequency range of 1–7 kHz, which are captured for the first time. The results show that three main frequency bands are present under both stable (Ma=0.6  i=5.0°) and unstable conditions (Ma=0.6  i=7.5°). It is found that the high-fluctuation regions of the three frequency bands occupy different spatial positions. Furthermore, combining the experimental results near the wall with the high-fidelity detached eddy simulation results far away from the wall, the physical phenomena related to the different frequency bands are explored through the spatial characteristics of the main fluctuation areas.
Designer pair statistics of disordered many-particle systems with novel properties
Authors: Wang Haina , Torquato Salvatore
Published: January 2024

The knowledge of exact analytical functional forms for the pair correlation function g2(r) and its corresponding structure factor S(k) of disordered many-particle systems is limited. For fundamental and practical reasons, it is highly desirable to add to the existing database of analytical functional forms for such pair statistics. Here, we design a plethora of such pair functions in direct and Fourier spaces across the first three Euclidean space dimensions that are realizable by diverse many-particle systems with varying degrees of correlated disorder across length scales, spanning a wide spectrum of hyperuniform, typical nonhyperuniform, and antihyperuniform ones. This is accomplished by utilizing an efficient inverse algorithm that determines equilibrium states with up to pair interactions at positive temperatures that precisely match targeted forms for both g2(r) and S(k). Among other results, we realize an example with the strongest hyperuniform property among known positive-temperature equilibrium states, critical-point systems (implying unusual 1D systems with phase transitions) that are not in the Ising universality class, systems that attain self-similar pair statistics under Fourier transformation, and an experimentally feasible polymer model. We show that our pair functions enable one to achieve many-particle systems with a wide range of translational order and self-diffusion coefficients D, which are inversely related to one another. One can design other realizable pair statistics via linear combinations of our functions or by applying our inverse procedure to other desirable functional forms. Our approach facilitates the inverse design of materials with desirable physical and chemical properties by tuning their pair statistics.
The limiting behavior of Riemann solutions to the hydrodynamic Aw-Rascle traffic model
Authors: Shen Chun , Sun Meina
Published: January 2024

The hydrodynamic Aw-Rascle traffic model is proposed by combining the Aw-Rascle model and the pressureless hydrodynamic model, whose Riemann solutions are solved explicitly based on the fine analysis of elementary waves. As the traffic pressure vanishes, the asymptotic behavior of Riemann solutions is analyzed carefully, in which the intrinsic nonlinear phenomena of concentration and cavitation are observed and explored. Moreover, it is found interestingly that the vanishing traffic pressure limit of the Riemann solution for the hydrodynamic Aw-Rascle traffic model is different obviously from the one for the pressureless hydrodynamic model under the specially designated circumstance due to the different choices of the over-compressive entropy conditions of delta shock wave.
Scope of practice regulation in medicine: balancing patient safety, access to care and professional autonomy
Authors: Gericke Christian A.
Published: January 2024

Scope of practice regulation in medicine is crucial for ensuring patient safety, access to care and professional autonomy. This paper explores the impact of scope of practice regulation on healthcare delivery, professional responsibilities and patient outcomes. It discusses the variability in standards for safe practice, the challenges in defining boundaries between medical specialties and the recent controversies in cosmetic surgery practice. The paper also examines the potential benefits and drawbacks of rigorous scope of practice regulations, including their impact on clinical innovation, flexibility and access to care. Furthermore, it delves into the implications of defensive medicine and the consequences of restrictive regulations on patient care. The author proposes implementing a proactive, national, artificial intelligence-powered, real-time outcome monitoring system to address these challenges. This system aims to cover every patient undergoing a surgical procedure and could be gradually extended to non-surgical conditions, benefiting all key stakeholders in the health system. The paper emphasises the need for a balanced approach to scope of practice regulation to avoid stifling clinical innovation and professional autonomy, while ensuring patient safety and professional accountability.
Meta-analysis of prevalence and associated risk factors for lameness in dairy cattle across tropical Asian nations
Authors: Patoliya Priyanka , Kataktalware Mukund A. , Sivaram Muniandy , G. Letha Devi , Jeyakumar Sakhtivel , Mech Anjumoni , Manimaran Ayyasamy , Ramesha Kerekoppa P.
Published: January 2024

Context Lameness in dairy cattle affects the health, welfare, performance, and profitability of dairy farms. Being multifactorial in nature, several animal and farm-level risk factors influence the severity and prevalence of lameness. Aims The objective of the present meta-analysis study was to provide a pooled estimate of the prevalence and identification of the potential risk factors associated with lameness in dairy cattle across tropical Asian countries. Methods A literature search reporting prevalence data for lameness in dairy cattle of tropical Asian countries including India, Bangladesh, Pakistan, Malaysia, Nepal and Thailand for the past 21 years (2000–2021) was collected by using appropriate keywords from the electronic databases. After removing outlier studies, a meta-analysis of 38 studies published in English was performed under a random-effects model by using the meta package (metaprop function) in R software. Key results The pooled estimate of the overall prevalence of lameness was 15.13% (95% confidence interval [CI] = 13.01, 17.53). High heterogeneity was found in the prevalence estimates among the published studies (P < 0.05). The pooled prevalence for lameness-related lesions was, for overgrown hooves 34.42% (95% CI = 23.41, 47.42), interdigital 28 hyperplasia 9.73% (95% CI = 5.84, 15.78), white line disease 6.91% (95% CI = 3.54, 13.05) and sole ulcer 6.84% (95% CI = 3.87, 11.83). The prevalence of lameness was higher in cows at parity three (23.03%) and at parity greater than or equal to 4 (31.68%) than at first and second parity. Breed of an animal, lower body condition score (BCS), housing and floor type, and season also had a significant effect on the pooled prevalence of lameness (P < 0.0001). Conclusions The findings of the present study showed that lameness is prevalent across the tropical Asian countries and there was a significant association of risk factors such as housing, floor, hygiene, and animal nutrition with lameness in dairy herds. Implications Meta-analysis study indicated that there is a need to adopt better management practices to minimise the incidence of lameness in dairy animals.
Improvement in thermoelectric properties of Zn–Mn co-doped nanostructured SnTe through band engineering and chemical bond softening
Authors: Bugalia Anita , Gupta Vivek , Pandey Abhishek
Published: January 2024

In this work, we used solvothermal technique to synthesize thermoelectrically viable Zn–Mn co-doped SnTe materials. However, the thermoelectric (TE) performance of pure SnTe is subpar due to the significant energy gap between its valence bands, inherent Sn-vacancies, and high electrical thermal conductivity. Band structure engineering and carrier concentration optimization of SnTe following Zn–Mn co-doping have the potential to enhance the Seebeck coefficient. In turn, a boost in the Seebeck coefficient significantly improved the power factor in Sn0.89Mn0.09Zn0.02Te by about five times as compared to pure SnTe at 473 K. The minimum lattice thermal conductivity (κ
L) in Sn0.89Mn0.09Zn0.02Te is 0.54 W m−1K−1 at 473 K, which is almost half that of pure SnTe. The lower lattice thermal conductivity of co-doped samples may be a result of (i) a decrease in phonon group velocity by chemical bond softening and (ii) phonon scattering caused by nanostructuring, point defects, and grain boundaries. Consequently, maximum zT = 0.11 has been achieved in Sn0.89Mn0.09Zn0.02Te at 473 K, which is about five times that of pristine SnTe. Material quality factor (B) of Sn0.89Mn0.09Zn0.02Te is almost triple that of pristine SnTe at 473 K, which implies that Zn–Mn co-doped SnTe is more suited to construct a TE device. An increase in electric transport properties (weighted mobility and electronic quality factor) and a decrease in κ
L after Zn–Mn co-doping contribute to the enhancement of B. The findings of this investigation suggest that the addition of Zn and Mn to SnTe can improve its TE performance.
Developing three-dimensional mechanical metamaterials with tailorable bandgaps for impact mitigation
Authors: Zhou Youchuan , Ye Lin , Chen Yuan
Published: January 2024

A novel three-dimensional mechanical metamaterial with low frequency bandgaps and negative Poisson’s ratio is designed, consisting of a conventional three-dimensional reentrant structure and periodic resonators, with the aim of achieving vibration isolation and impact mitigation. The bandgap characteristic of the proposed metamaterial is determined computationally, and its dispersion diagram exhibits both partial bandgaps and a complete bandgap within a frequency band of interest. The mechanism for bandgap occurrence is characterised as the local resonance of ligaments and resonators, according to a vibration mode analysis. The wave attenuation capacity of the proposed metamaterial is derived numerically and experimentally from semi-infinite and finite-size metamaterial models, showing a good agreement with the predicted bandgap. Additionally, a thorough study on the design flexibility indicates that the bandgap characteristic can be directly tailored by changing the geometrical parameters of the proposed metamaterial. This allows further optimisation of the metamaterial for potential applications. The dynamic performance of the proposed metamaterial under an impact load is investigated by a finite element model. This demonstrates that the metamaterial reduces the transmitted force by a factor of 1.6 (for peak value) and 2.0 (for root mean square value) under a pulse impact with a duration of 0.88 ms. The impact mitigation result obtained from the impact test confirms that the metamaterial shows a mitigation capacity which is approximately 20% better than that of the conventional reentrant structure.
Topological aspects of multi-k antiferromagnetism in cubic rare-earth compounds
Authors: Simeth W , Rahn M C , Bauer A , Meven M , Pfleiderer C
Published: January 2024

We advertise rare-earth intermetallics with high-symmetry crystal structures and competing interactions as a possible materials platform hosting spin structures with non-trivial topological properties. Focusing on the series of cubic RCu compounds, where R = Ho, Er, Tm, the bulk properties of these systems display exceptionally rich magnetic phase diagrams hosting an abundance of different phase pockets characteristic of antiferromagnetic order in the presence of delicately balanced interactions. The electrical transport properties exhibit large anomalous contributions suggestive of topologically non-trivial winding in the electronic and magnetic structures. Neutron diffraction identifies spontaneous long-range magnetic order in terms of commensurate and incommensurate variations of

(
π
π
0
)

antiferromagnetism with the possibility for various multi-
k
configurations. Motivated by general trends in these materials, we discuss the possible existence of topologically non-trivial winding in real and reciprocal space in the class of RCu compounds including antiferromagnetic skyrmion lattices. Putatively bringing together different limits of non-trivial topological winding in the same material, the combination of properties in RCu systems promises access to advanced functionalities.
Vernier-effect-based fiber microcoupler for highly sensitive liquid refractive index sensing
Authors: Sun Hanchao , Wu Jixuan , Song Binbin , Liu Haifeng , Duan Shaoxiang , Liu Xiao
Published: January 2024

An orthogonal mode interferometer (OMI) is proposed and experimentally demonstrated for liquid refractive index sensing using the optical Vernier effect. The OMIs are based on weakly fiber microcouplers, which are fabricated by fusing single mode fiber and coreless fiber together. Owing to the birefringent characteristic of the hybrid coupler, the optical Vernier effect is dependent on the overlap of mode interference between the x and y polarizations. Compared to the response of the individual resonance dip, the signal demodulation of the Vernier envelope exhibits more excellent signal amplification capability. Experimental results show that the Vernier envelope of the OMI achieves a refractive index (RI) sensitivity of 22 427.03 nm/RIU near the RI of 1.33 with a magnification factor of 4.1. Moreover, with its high sensitivity, flexible design and simplified configuration, our proposed OMI based on the optical Vernier effect is well suitable for a wide range of biosensing applications.
Synergistic integration of Ni-metal organic framework/SnS2 nanocomposite and nickel foam electrode for ultrasensitive and selective electrochemical detection of albumin in simulated human blood serum
Authors: Singh Pratiksha , Aggrawal Vinayak , Badhulika Sushmee
Published: January 2024

Albumin is a vital blood protein responsible for transporting metabolites and drugs throughout the body and serves as a potential biomarker for various medical conditions, including inflammatory, cardiovascular, and renal issues. This report details the fabrication of Ni-metal organic framework/SnS2 nanocomposite modified nickel foam electrochemical sensor for highly sensitive and selective non enzymatic detection of albumin in simulated human blood serum samples. Ni-metal organic framework/SnS2 nanocomposite was synthesized using solvothermal technique by combining Ni-metal–organic framework (MOF) with conductive SnS2 leading to the formation of a highly porous material with reduced toxicity and excellent electrical conductivity. Detailed surface morphology and chemical bonding of the Ni-MOF/SnS2 nanocomposite was studied using scanning electron microscopy, transmission electron microscopy, Fourier transform infra-red, and Raman analysis. The Ni-MOF/SnS2 nanocomposite coated on Ni foam electrode demonstrated outstanding electrochemical performance, with a low limit of detection (0.44 μM) and high sensitivity (1.3 μA/pM/cm2) throughout a broad linear range (100 pM–10 mM). The remarkable sensor performance is achieved through the synthesis of a Ni-MOF/SnS2 nanocomposite, enhancing electrocatalytic activity for efficient albumin redox reactions. The enhanced performance can be attributed due to the structural porosity of nickel foam and Ni-metal organic framework, which favours increased surface area for albumin interaction. The presence of SnS2 shows stability in acidic and neutral solutions due to high surface to volume ratio which in turn improves sensitivity of the sensing material. The sensor exhibited commendable selectivity, maintaining its performance even when exposed to potential interfering substances like glucose, ascorbic acid, K+, Na+, uric acid, and urea. The sensor effectively demonstrates its accuracy in detecting albumin in real samples, showcasing substantial recovery percentages of 105.1%, 110.28%, and 91.16%.
Thermodynamic description of active brownian particle driven by fractional gaussian noise
Authors: Rangaig Norodin A
Published: January 2024

As a natural extension of the recent results on the thermodynamics of an active Brownian particle (self-propelled), we study the thermodynamics of an active Brownian particle (ABP) driven by fractional Gaussian noise (FGN). To serve as a prelude of the main results, we start from the conventional Markov process but with time dependent diffusion coefficient, where deviation in integral fluctuation relation (IFR) for total entropy production requires a general definition of the temperature, following the same case for a Brownian particle. In other words, the general temperature definition for this case is independent to the statistics of the rotational motion. We then proceed with the main problem of the paper, which is an active Brownian particle driven by fractional Gaussian noise. Under the assumption that self-propulsion is even under time-reversal, temperature is defined as well as the distance on how far the IFR for total entropy production deviates from the standard definition by adopting the standard definition of trajectory-level entropy and the joint probability of ABP. Furthermore, second law-like concept based on the found deviation is derived, as well as a generalized Clausius inequality. Lastly, magnitude of this deviation diminishes in the case of pure white noise.
Particle dynamics on test papapetrou fields of vacuum spacetimes
Authors: Maier Rodrigo
Published: January 2024

In this paper we examine the dynamics of test particles subjected to Papapetrou fields which emerge from vacuum spacetimes isometries. Assuming that the background geometry is described by a Kerr metric whose timelike Killing vector satisfies Maxwell equations, we evaluate the electromagnetic fields—Papapetrou fields—by fixing a locally non-rotating (LNR) frame of reference. We also evaluate such the electromagnetic fields for a vanishing rotation parameter assuming a timelike frame of reference for a Schwarzschild background. In order to probe for the effect of the test Papapetrou fields we study the motion of charged particles in a Kerr background. Restricting ourselves to orbits in the equatorial plane with LNR initial conditions we show that there is an explicit deviation between orbits of neutral and charged particles in the case of repulsive electromagnetic configurations. For critical charge-mass ratios ζ
* test particles can be found in the Kerr retrograde photon sphere. For static configurations we show that massive/charged test particles may populate the unstable Schwarzschild photon sphere for given domain of the parameter space.
A Scalable optical meta-surface glazing design for agricultural greenhouses
Authors: Lakshminarayanan Venkatasubramanian , Ranjbar Mostafa , Ibrahim Khalifa Aliyu , Luo Zhenhua
Published: January 2024

Optical meta-surfaces allow controllable reflection and transmission spectra in both optical and infrared regions. In this study, we explore their potential in enhancing the performance of low-emission glazing designed for improved energy efficiency, for agricultural greenhouses in cold climates. The low-emission glazing employs thin film optics to retain heat by allowing solar radiation while reflecting radiation emitted by room-temperature objects. The incorporation of metamaterials that can be scalably manufactured and designed for capturing solar energy in the mid-infrared spectrum, offers an opportunity to further enhance the glazing’s energy efficiency. Based on existing literature, the finite difference time domain (FDTD) method and the transfer matrix method are utilised to propose a metamaterial structure, with spherical silver nanoparticles and thin-films. We compare the performance of this proposed design against existing materials. The outcome of this study offers insights into the potential of metamaterials in optimizing the energy efficiency of cold-climate agricultural greenhouses.
Synergistic effects of W–Ta alloys exposed to various ELM-like fusion events
Authors: Ray Tyler E , Tripathi Jitendra Kumar , Hassanein Ahmed
Published: January 2024

Recently tungsten alloys have shown capabilities in suppressing morphological changes when exposed to harsh fusion conditions. Morphological changes due to He+ and D+ ions at high temperatures (1000–2000 K) can lead to easier erosion and sputtering of tungten (W) particles towards quenching the fusion plasma. This study investigated W–3Ta alloy as potential plasma facing materials (PFMs) exposed to different edge-localized mode (ELM)-like energies and ion loadings. Performance of W–3Ta has been tested as a function of ELM-like energies (0.6–1.5 GW m−2) and varying He+ and D+ ion concentrations (100% He+, 50% He+:50% D+,10% He+:90% D+ (similar ELM-like reactor condition), and 100% D+ ions). Early-stage fuzz formation and surface pores were observed during 100% He+ ion irradiation and mixed ion loadings but not observed during 100% D+ ion loadings. Pores decreased in quantity and increased in size with increasing transient heat loading. Grain boundaries acted as trapping sites of helium and deuterium atoms during dual beam ion irradiations, as observed through increased pore size along the grain boundary. Qualitative erosion estimates were measured using witness plates. Increased erosion was observed with increasing D+ ion concentration, which is attributed to D supersaturation in the near surface region affecting thermal and mechanical properties. More erosion was observed for W–3Ta samples compared to pure W, evident through large (>10 µm) cracks on the surface, and an increase in W metal x-ray photoelectron spectroscopy peaks under similar loading conditions. The slight enhancement in erosion is attributed to the slightly decreased thermal properties, ∼10% thermal diffusivity drop, of W–3Ta at high temperatures. The damage threshold was impacted by ion loading, where distinct cracking was observed for 100% He+ at a lower heat loading. This matrix study using reactor-like loading supports the need for extensive studies on future W alloy PFMs before selecting one as an alternative.
First numerical analysis of runaway electron generation in tungsten-rich plasmas towards ITER
Authors: Walkowiak J. , Hoppe M. , Ekmark I. , Jardin A. , Bielecki J. , Król K. , Savoye-Peysson Y. , Mazon D. , Dworak D. , Scholz M.
Published: January 2024

The disruption and runaway electron analysis model code was extended to include tungsten impurities in disruption simulations with the aim of studying the runaway electron (RE) generation. This study investigates RE current sensitivity on the following plasma parameters and modelling choices: tungsten concentration, magnetic perturbation strength, electron modelling, thermal quench time and tokamak geometry—ITER-like or ASDEX-like. Our investigation shows that a tungsten concentration below 10−3 does not cause significant RE generation on its own. However, at higher concentrations it is possible to reach a very high RE current. Out of the two tested models of electrons in plasma: fluid and isotropic (kinetic), results from the fluid model are more conservative, which is useful when it comes to safety analysis. However, these results are overly pessimistic when compared to the isotropic model, which is based on a more reliable approach. Our results also show that the hot-tail RE generation mechanism is dominant as a primary source of RE in tungsten induced disruptions, usually providing orders of magnitude higher RE seed than Dreicer generation. We discuss best practices for simulations with tungsten-rich plasma, present the dependence of the safety limits on modelling choices and highlight the biggest shortcoming of the current simulation techniques. The obtained results pave the way for a wider analysis of tungsten impact on the disruption dynamics, including the mitigation techniques for ITER in the case of strong contamination of the plasma with tungsten.
Air quality and public health co-benefits of 100% renewable electricity adoption and electrification pathways in Los Angeles
Authors: Li Yun , Ravi Vikram , Heath Garvin , Zhang Jiachen , Vahmani Pouya , Lee Sang-Mi , Zhang Xinqiu , Sanders Kelly T , Ban-Weiss George A
Published: January 2024

To demonstrate how a mega city can lead in decarbonizing beyond legal mandates, the city of Los Angeles (LA) developed science-based, feasible pathways towards utilizing 100% renewable energy for its municipally-owned electric utility. Aside from decarbonization, renewable energy adoption can lead to co-benefits such as improving urban air quality from reductions in combustion-related emissions of oxides of nitrogen (NOx), primary fine particulate matter (PM2.5) and others. Herein, we quantify changes to air pollutant concentrations and public health from scenarios of 100% renewable electricity adoption in LA in 2045, alongside aggressive electrification of end-use sectors. Our analysis suggests that while ensuring reliable electricity supply, reductions in emissions of air pollutants associated with the 100% renewable electricity scenarios can lead to 8% citywide reductions of PM2.5 concentration while increasing ozone concentration by 5% relative to a 2012 baseline year, given identical meteorology conditions. The combination of these concentration changes could result in net monetized public health benefits (driven by avoided deaths) of up to $1.4 billion in year 2045 in LA, results potentially replicable for other city-scale decarbonization scenarios.
Effective interaction between guest charges immersed in 2D jellium
Authors: Šamaj Ladislav
Published: January 2024

The model under study is an infinite 2D jellium of pointlike particles with elementary charge e, interacting via the logarithmic potential and in thermal equilibrium at the inverse temperature β. Two cases of the coupling constant

Γ
≡
β

e
2

are considered: the Debye–Hückel limit

Γ
→
0

and the free-fermion point

Γ
=
2

. In the most general formulation, two guest particles, the one with charge

q
e

(the valence q being an arbitrary integer) and the hard core of radius σ > 0 and the pointlike one with elementary charge e, are immersed in the bulk of the jellium at distance

d
⩾
σ

. Two problems are of interest: the asymptotic large-distance behavior of the excess charge density induced in the jellium and the effective interaction between the guest particles. Technically, the induced charge density and the effective interaction are expressed in terms of multi-particle correlations of the pure (translationally invariant) jellium system. It is shown that the separation form of the induced charge density onto its radial and angle parts, observed previously in the limit

Γ
→
0

, is not reproduced at the coupling

Γ
=
2

. Based on an exact expression for the effective interaction between guest particles at

Γ
=
2

, oppositely (

q
=
0
,
−
1
,
−
2
,
…

) charged guest particles always attract one another while likely (

q
=
1
,
2
,
…

) charged guest particles repeal one another up to a certain distance d between them and then the mutual attraction takes place up to asymptotically large (finite) distances.
Influence of urban growth on urban heat island phenomenon around Jakarta, Indonesia: Insight from Depok and South Tangerang city
Authors: Jumadi  , Novita Sari Dewi , Fikriyah Vidya N. , Aditya Pratama Bayu , Wardah Haniyatul , Triasa Madani Darin , Dwi Priyono Kuswaji , Zaky Hadibasyir Hamim , Danardono  , Saputra Aditya
Published: January 2024

Economic activities in developing countries play a crucial role in national development. Jakarta, as one of the growing hubs in Indonesia, is influencing the urban planning of neighboring cities. Depok and South Tangerang City are among the cities that are most impacted by Jakarta’s growth. One of the impacts is that those cities are experiencing accelerated urbanization. This condition has caused a rise in the surface temperature of metropolitan areas, known as the Urban Heat Island (UHI) effect. This study used multi-temporal Landsat 8 OLI data to determine the land cover and Land Surface Temperature (LST) in the two cities. The relation between those variables was then evaluated using simple regression. The results show that common conditions occurred in those two cities.
Assessment of Farmworker’s Level of Knowledge in Banana Cultivation and its Implication on Productivity Improvement in the Lower Shabelle Region of Somalia
Authors: Daud Farah Ifrah , Visetnoi Supawan
Published: January 2024

Somalia was the largest banana producer and exporter in Africa in early 1990, but both production and export collapsed due to improper use of good agricultural practices and post-harvesting constraints. The government and its partners tried to recover the banana sector, but nothing changed. Researchers hypothesized that studying and improving farmworkers’ knowledge of banana cultivation could contribute to recovering the country’s banana sector. Therefore, the study objective is to study the current knowledge level of banana farm workers on banana cultivation and contributing factors influencing farm workers’ knowledge of banana cultivation in the Lower Shabelle region of Somalia. A cross-sectional study participating 400 farmworkers was implemented in the selected six large-scale banana farms which are the largest production area of the Lower Shabelle region of Somalia by using a well-structured questionnaire. Bloom’s cut-of-point classification was used to categorize knowledge scores into three knowledge levels and data were analysed using descriptive statistics, Chi-square test, and Multiple linear regression at a p-value of <0.05, <0.10, and <0.01. Most of the farm workers (80.2%) were male with 31.57 mean age (SD=8.53) and 167.48 mean income age (SD=81.27). This study reported that 194 (48.5%) farm workers have low knowledge of banana cultivation, 127 (31.8%) have moderate knowledge, and only 79 (19.8%) have good knowledge. The Mean knowledge was 18.54 (SD=6.51) out of 30 maximum expected scores. The weakest knowledge section is pesticide management while the strongest is harvesting. The coefficient of farmworkers’ age, education, training participation, and banana farming experience are significantly associated with their knowledge of banana cultivation activities at p-value <0.05 while the total land size they cultivate has a significant association at p-value <0.10. This study reported almost half of the banana farm workers have a low level of knowledge of banana cultivation. To enhance farmworkers’ cultivation knowledge, agricultural extension and education programs must enhance pesticide management relating knowledge by specifically focusing on older and low-experience farmworkers, rural farmworkers that are far away from training centres, and those who do not have large land sizes. In addition, improving training quality by providing advanced training materials and mentors, increasing training frequency, and improving training effectiveness is highly recommended.
Green Open Space Development as a Green City Concept Implementation Strategy (Case Study in Samarinda City)
Authors: Setyasih Iya’ , Prananto Sulistyo Sidiq , Rahman Tamrin , Chandra Krisna P , Anwar Yaskinul , Juhardika Aureliya C
Published: January 2024

The rapid growth and development of the city has been experienced by various regions, one of which is Samarinda City, which is the capital of East Kalimantan Province. As a result of the development of Samarinda City, causing environmental problems accompanied by other negative impacts. To deal with and solve these problems, the method determined by the Samarinda City government is by implementing the green city concept. One of them is the development of green open space as an indicator of the green city concept. Through observation, interviews and documentation, the results of the research were (1) only about 10% of Samarinda City’s green open spaces, (2) the constraints faced were limited land, insufficient budget, land acquisition, violations of provisions on land and building use, lack of coordination between implementers of RTH providers, as well as the lack of compliance and understanding of the public regarding green open spaces, (3) The strategy implemented by the Samarinda City Government in implementing the green city concept is, providing green open space through the ProBebaya program, increasing community compliance and implementing private green open space regulations, providing sanctions, and socialization of the importance of green open space.
Potential Carbon Accumulation Rate in the Sediment Mangroves at Ujung Kulon National Park, Banten, Indonesia
Authors: Shintianata D , Patria M P , Lubis A A , Sugiharto U
Published: January 2024

As one of the wealthiest countries in the world in terms of the mangrove, Indonesia has a significant potential contributor to blue carbon. This study determines carbon stock (Corg) and sediment accumulation rate (SAR) to find the carbon accumulation rate (CAR) in sediment mangroves at Ujung Kulon National Park. Sampling was taken in 3 locations perpendicular to the shoreline: interior, fringe, and mudflat. The result shows that the interior area has the highest CAR (31.94 ± 3.6 g C m−2 yr−1) even though the carbon stock (90.19 Mg C ha−1) is the lowest from the other two. On the contrary, mudflat, which has the highest carbon stock (169.6 Mg C ha−1), shows the lowest CAR (17.03 ± 5.21 g C m−2 yr−1). This suggests that differences in sedimentation rates contribute to the variations in CAR.
Biomass Stock Estimation Using Landsat 8 Imagery in Bukit Tigapuluh National Park, Riau
Authors: Ash-Shidiq I P , Supriatna S , Darmawan A , Warta Z , Molidena E , Valla A , Hisan  , Firdaus M I , Zakaria N A , Muafiroh S , Pradana M R , Putera D A
Published: January 2024

Forests certainly store biomass content which is reflected in the physical appearance of a tree. In calculating biomass directly, direct surveys and measurements are needed. Remote sensing technology, in this case, is a tool for monitoring and calculating the biomass content of vegetation. In estimating biomass using remote sensing, the biomass content of vegetation in the field is still needed. This study aimed to estimate the biomass content of the Meranti plant (Shorea parvifolia Dyer), which is the dominant plant species in the Bukit Tigapuluh National Park in Indragiri Hulu and Indragiri Hilir Regencies, Riau Province and Tebo Regencies and Tanjung Jabung Barat Regencies in Jambi Province with using Landsat 8 imagery. Field measurements and remote sensing images, which in this case are vegetation indices in the form of NDVI, ARVI, GNDVI, MSAVI2, and EVI, will produce a biomass estimation model, and the most suitable model will be selectively selected based on the strength of the relationship between the two parameters. The resulting model between the biomass value and the vegetation index will then become an estimate of the biomass of the dominant plant species in Bukit Tigapuluh National Park.
The effect of vegetation index on the land surface temperature in South Badung Regency, Bali Province
Authors: Dimyati Muhammad , Aginta Friscila , Damayanti Astrid
Published: January 2024

The land surface temperature (LST) is a crucial component of the earth’s energy balance system. The temperature differences between the earth’s surface and the atmosphere are reflected in LST. Conversion of land, including vegetated land, may result in changes to LST. Using the vegetation index approach—NDVI and EVI—this study seeks to ascertain how variations in vegetation density impact LST. Using Landsat 7 ETM+ satellite imagery from 2003 and Landsat 8 OLI-TIRS from 2015 and 2020, this research combines remote sensing technologies and GIS to get vegetation density and LST values, which were then subjected to field verification and spatiotemporal analysis. According to the study’s findings, variations in vegetation density and soil surface temperature have an inverse or opposing relationship. The study’s findings suggest that variations in vegetation density and soil surface temperature have an opposing or inverse connection. In South Badung Regency, places with low vegetation density vary more in proximity to metropolitan areas, resulting in higher soil surface temperatures. These findings suggest that several additional factors, including population density and size, land use, urban planning, rainfall, and season, influence variations in land surface temperature in South Badung Regency.
An autoencoder for heterotic orbifolds with arbitrary geometry
Authors: Escalante–Notario Enrique , Portillo–Castillo Ignacio , Ramos–Sánchez Saúl
Published: January 2024

Artificial neural networks can be an important tool to improve the search for admissible string compactifications and characterize them. In this paper we construct the heterotic orbiencoder, a general deep autoencoder to study heterotic orbifold models arising from various Abelian orbifold geometries. Our neural network can be easily trained to successfully encode the large parameter space of many orbifold geometries simultaneously, independently of the statistical dissimilarities of their training features. In particular, we show that our autoencoder is capable of compressing with good accuracy the large parameter space of two promising orbifold geometries in just three parameters. Further, most orbifold models with phenomenologically appealing features appear in bounded regions of this small space. Our results hint towards a possible simplification of the classification of (promising) heterotic orbifold models.
A phenomenological figure of merit for photovoltaic materials
Authors: Crovetto Andrea
Published: January 2024

I derive a figure of merit (FOM)

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P
V

to estimate the maximum efficiency attainable by a generic non-ideal photovoltaic (PV) absorber in a planar single-junction solar cell. This efficiency limit complements the more idealized limits derived from fundamental physics, such as the Shockley–Queisser (SQ) limit and its subsequent generalizations. Specifically, the present FOM approach yields stricter efficiency limits applicable to realistic PV absorbers with various imperfections, including finite carrier mobilities and doping densities.

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P
V

is a function of eight properties of the absorber that are both measurable by experiment and computable by electronic structure methods. They are: band gap, non-radiative carrier lifetime, carrier mobility, doping density, static dielectric constant, effective mass, and two parameters describing the spectral average and dispersion of the light absorption coefficient.

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has high predictive power (absolute efficiency error less than

±
1.1
%

) and wide applicability range. The SQ limit and its generalizations are reproduced by

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. Simpler FOMs proposed by others are also included as special cases of

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.
N-cadherin and β1 integrin coordinately regulate growth plate cartilage architecture
Authors: Greer Sydney E. , Haller Stephen J. , Lee Donghee , Dudley Andrew T.
Published: January 2024

Spatial and temporal regulation of chondrocyte maturation in the growth plate drives growth of many bones. One essential event to generate the ordered cell array characterizing growth plate cartilage is the formation of chondrocyte columns in the proliferative zone via 90-degree rotation of daughter cells to align with the long axis of the bone. Previous studies have suggested crucial roles for cadherins and integrin β1 in column formation. The purpose of this study was to determine the relative contributions of cadherin- and integrin-mediated cell adhesion in column formation. Here we present new mechanistic insights generated by application of live time-lapse confocal microscopy of cranial base explant cultures, robust genetic mouse models, and new quantitative methods to analyze cell behavior. We show that conditional deletion of either the cell−cell adhesion molecule Cdh2 or the cell−matrix adhesion molecule Itgb1 disrupts column formation. Compound mutants were used to determine a potential reciprocal regulatory interaction between the two adhesion surfaces and identified that defective chondrocyte rotation in a N-cadherin mutant was restored by a heterozygous loss of integrin β1. Our results support a model for which integrin β1, and not N-cadherin, drives chondrocyte rotation and for which N-cadherin is a potential negative regulator of integrin β1 function.
Geomagnetic twin satellites MSS-1: progress and future plans
Authors: Livermore Phil , Brown William , Beggan Ciarán , Gubbins David
Published: January 2024

Phil Livermore, William Brown, Ciarán Beggan and David Gubbins report on the RAS Specialist Discussion Meeting on Geomagnetic Twin satellites MSS-1: progress and future plans
Astrobiology: life detection and the abiotic baseline
Authors: McMahon Sean , Cockell Charles
Published: January 2024

Sean McMahon and Charles Cockell report on the RAS Specialist Discussion Meeting dedicated to sifting through the steps and mis-steps towards finding life off Earth
iCluF: an unsupervised iterative cluster-fusion method for patient stratification using multiomics data
Authors: Shakyawar Sushil K , Sajja Balasrinivasa R , Patel Jai Chand , Guda Chittibabu
Published: January 2024

Motivation

Patient stratification is crucial for the effective treatment or management of heterogeneous diseases, including cancers. Multiomic technologies facilitate molecular characterization of human diseases; however, the complexity of data warrants the need for the development of robust data integration tools for patient stratification using machine-learning approaches.

Results

iCluF iteratively integrates three types of multiomic data (mRNA, miRNA, and DNA methylation) using pairwise patient similarity matrices built from each omic data. The intermediate omic-specific neighborhood matrices implement iterative matrix fusion and message passing among the similarity matrices to derive a final integrated matrix representing all the omics profiles of a patient, which is used to further cluster patients into subtypes. iCluF outperforms other methods with significant differences in the survival profiles of 8581 patients belonging to 30 different cancers in TCGA. iCluF also predicted the four intrinsic subtypes of Breast Invasive Carcinomas with adjusted rand index and Fowlkes–Mallows scores of 0.72 and 0.83, respectively. The Gini importance score showed that methylation features were the primary decisive players, followed by mRNA and miRNA to identify disease subtypes. iCluF can be applied to stratify patients with any disease containing multiomic datasets.

Availability and implementation

Source code and datasets are available at https://github.com/GudaLab/iCluF_core.
Dual-energy CT applications in musculoskeletal disorders
Authors: Cheong Sook Chuei W , Yan Yet Yen , Sheikh Adnan , Ouellette Hugue A , Munk Peter L , Murray Nicolas , Mallinson Paul I
Published: January 2024

Dual-energy CT (DECT) is an exciting application in CT technology conferring many advantages over conventional single-energy CT at no additional with comparable radiation dose to the patient. Various emerging and increasingly established clinical DECT applications in musculoskeletal (MSK) imaging such as bone marrow oedema detection, metal artefact reduction, monosodium urate analysis, and collagen analysis for ligamentous, meniscal, and disc injuries are made possible through its advanced DECT post-processing capabilities. These provide superior information on tissue composition, artefact reduction and image optimization. Newer DECT applications to evaluate fat fraction for sarcopenia, Rho/Z application for soft tissue calcification differentiation, 3D rendering, and AI integration are being assessed for future use. In this article, we will discuss the established and developing applications of DECT in the setting of MSK radiology as well as the basic principles of DECT which facilitate them.
Evaluation of renal function in chronic kidney disease using histogram analysis based on multiple diffusion models
Authors: Zhong Guimian , Chen Luyan , Lin Zhiping , Xiang Zhiming
Published: January 2024

Objectives

To compare the diagnostic value of histogram features of multiple diffusion metrics in predicting early renal impairment in chronic kidney disease (CKD).

Methods

A total of 77 patients with CKD (mild group, estimated glomerular filtration rate (eGFR) ≥60 mL/min/1.73 m2) and 30 healthy controls (HCs) were enrolled. Diffusion-weighted imaging was performed by using single-shot echo planar sequence with 13 b values (0, 20, 50, 80, 100, 150, 200, 500, 800, 1000, 1500, 2000, and 2500 s/mm2). Diffusion models including mono-exponential (Mono), intravoxel incoherent motion (IVIM), stretched-exponential (SEM), and kurtosis (DKI) were calculated, and their histogram features were analysed. All diffusion models for predicting early renal impairment in CKD were established using logistic regression analysis, and diagnostic efficiency was compared among the models.

Results

All diffusion models had high differential diagnosis efficiency between the mild group and HCs. The areas under the curve (AUCs) of Mono, IVIM, SEM, DKI, and the combined diffusion model for predicting early renal impairment in CKD were 0.829, 0.809, 0.760, 0.825, and 0.861, respectively. There were no significant differences in AUCs except SEM and combined model, SEM, and DKI model. There were significant correlations between eGFR/serum creatinine and some of histogram features.

Conclusions

Histogram analysis based on multiple diffusion metrics was practicable for the non-invasive assessment of early renal impairment in CKD.

Advances in knowledge

Advanced diffusion models provided microstructural information. Histogram analysis further reflected histological characteristics and heterogeneity. Histogram analysis based on multiple diffusion models could provide an accurate and non-invasive method to evaluate the early renal damage of CKD.