bluuebunny/crossref_metadata_2025_split huggingface dataset:
Growth of quasi-1 dimensional (Bi1−x
Sb
x
)2S3 nanowires on fluorine-doped tin oxide glass substrate by vapor transport
Authors: Oh Seung Hwan , Izziyah Asna N , Kim Yong 
Published: March 2023

Abstract
(Bi1−x
Sb
x
)2S3 solid solution nanowires (

0
≤
x
≤
0.73

) are grown on fluorine-doped tin oxide (FTO) glass via physical vapor transport. The compositions were controlled by varying the Sb2S3 source temperature (300 °C–453 °C) by changing the upstream locations of the Sb2S3 source in the furnace while keeping the Bi2S3 source at the center of the furnace (497 °C). Defect-free nanowires with phase-pure orthorhombic and quasi-1 dimensional crystal structures were grown under a modified vapor–solid mechanism affected by FTO at initial growth stage. The aspect ratios of the nanowires reached the minimum at composition

x
∼
0.6
.

As the Sb2S3 source approached the Bi2S3 source, x increased owing to the increase in the Sb2S3 source temperature. x/(1-x), which is proportional to the evaporation flux of the Sb2S3 source, could be well-fitted with a thermally activated equation with an apparent activation energy (

105

kJ

mol

-
1

). However, at the distance between the Sb2S3 and Bi2S3 sources, with the Sb2S3 source at temperatures higher than 410 °C, the compositions reduced despite the increased Sb2S3 evaporation flux. Such retrograde behavior was confirmed by high-resolution transmission electron microscopy, x-ray diffraction, and micro-Raman studies. This retrograde behavior is ascribed to the loss due to the reaction of gaseous Sb species with the Bi2S3 source.
JAAL-Net: a joint attention and adversarial learning network for skin lesion segmentation
Authors: Xiong Siyu , Pan Lili , Lei Qianhui , Ma Junyong , Shao Weizhi , Beckman Eric 
Published: March 2023

Abstract

Objective. Skin lesion segmentation plays an important role in the diagnosis and treatment of melanoma. Existing skin lesion segmentation methods have trouble distinguishing hairs, air bubbles, and blood vessels around lesions, which affects the segmentation performance. Approach. To clarify the lesion boundary and raise the accuracy of skin lesion segmentation, a joint attention and adversarial learning network (JAAL-Net) is proposed that consists of a generator and a discriminator. In the JAAL-Net, the generator is a local fusion network (LF-Net) utilizing the encoder-decoder structure. The encoder contains a convolutional block attention module to increase the weight of lesion information. The decoder involves a contour attention to obtain edge information and locate the lesion. To aid the LF-Net generate higher confidence predictions, a discriminant dual attention network is constructed with channel attention and position attention. Main results. The JAAL-Net is evaluated on three datasets ISBI2016, ISBI2017 and ISIC2018. The intersection over union of the JAAL-Net on the three datasets are 90.27%, 89.56% and 80.76%, respectively. Experimental results show that the JAAL-Net obtains rich lesion and boundary information, enhances the confidence of the predictions, and improves the accuracy of skin lesion segmentation. Significance. The proposed approach effectively improves the performance of the model for skin lesion segmentation, which can assist physicians in accurate diagnosis well.
18F-PSMA-1007 salivary gland dosimetry: comparison between different methods for dose calculation and assessment of inter- and intra-patient variability
Authors: Pistone Daniele , Gnesin Silvano , Auditore Lucrezia , Italiano Antonio , Cascini Giuseppe Lucio , Amato Ernesto , Cicone Francesco 
Published: March 2023

Abstract

Objective. Simplified calculation approaches and geometries are usually adopted for salivary glands (SGs) dosimetry. Our aims were (i) to compare different dosimetry methods to calculate SGs absorbed doses (ADs) following [18F]-PSMA-1007 injection, and (ii) to assess the AD variation across patients and single SG components. Approach. Five patients with prostate cancer underwent sequential positron-emission tomography/computed tomography (PET/CT) acquisitions of the head and neck, 0.5, 2 and 4 h after [18F]-PSMA-1007 injection. Parotid and submandibular glands were segmented on CT to derive SGs volumes and masses, while PET images were used to derive Time-Integrated Activity Coefficients. Average ADs to single SG components or total SG (tSG) were calculated with the following methods: (i) direct Monte Carlo simulation with GATE/GEANT4 considering radioactivity in the entire PET/CT field-of-view (MC) or in the SGs only (MCsgo); (ii) spherical model (SM) of OLINDA/EXM 2.1, adopting either patient-specific or standard ICRP89 organ masses (SMstd); (iii) ellipsoidal model (EM); (iv) MIRD approach with organ S-factors from OLINDA/EXM 2.1 and OpenDose collaboration, with or without contribution from cross irradiation originating outside the SGs. The maximum percent AD difference across SG components (δ
max) and across patients (Δmax) were calculated. Main results. Compared to MC, ADs to single SG components were significantly underestimated by all methods (average relative differences ranging between −11.9% and −30.5%). δ
max values were never below 25%. The highest δ
max (=702%) was obtained with SMstd. Concerning tSG, results within 10% of the MC were obtained only if cross-irradiation from the remainder of the body or from the remainder of the head was accounted for. The Δmax ranged between 58% and 78% across patients. Significance. Simple geometrical models for SG dosimetry considerably underestimated ADs compared to MC, particularly if neglecting cross-irradiation from neighboring regions. Specific masses of single SG components should always be considered given their large intra- and inter-patient variability.
PET AIF estimation when available ROI data is impacted by dispersive and/or background effects
Authors: O’Sullivan Finbarr 
Published: March 2023

Abstract

Objective. Blood pool region of interest (ROI) data extracted from the field of view of a PET scanner can be impacted by both dispersive and background effects. This circumstance compromises the ability to correctly extract the arterial input function (AIF) signal. The paper explores a novel approach to addressing this difficulty. Approach. The method involves representing the AIF in terms of the whole-body impulse response (IR) to the injection profile. Analysis of a collection/population of directly sampled arterial data sets allows the statistical behaviour of the tracer’s impulse response to be evaluated. It is proposed that this information be used to develop a penalty term for construction of a data-adaptive method of regularisation estimator of the AIF when dispersive and/or background effects maybe impacting the blood pool ROI data. Main results. Computational efficiency of the approach derives from the linearity of the impulse response representation of the AIF and the ability to substantially rely on quadratic programming techniques for numerical implementation. Data from eight different tracers, used in PET cancer imaging studies, are considered. Sample image-based AIF extractions for brain studies with: 18F-labeled fluoro-deoxyglucose and fluoro-thymidine (FLT), 11C-labeled carbon dioxide (CO2) and 15O-labeled water (H2O) are presented. Results are compared to the true AIF based on direct arterial sampling. Formal numerical simulations are used to evaluate the performance of the AIF extraction method when the ROI data has varying amounts of contamination, in comparison to a direct approach that ignores such effects. It is found that even with quite small amounts of contamination, the mean squared error of the regularised AIF is significantly better than the error associated with direct use of the ROI data. Significance. The proposed IR-based AIF extraction scheme offers a practical methodological approach for situations where the available image ROI data may be contaminated by background and/or dispersion effects.
Statistical genetics in and out of quasi-linkage equilibrium
Authors: Dichio Vito , Zeng Hong-Li , Aurell Erik 
Published: March 2023

Abstract
This review is about statistical genetics, an interdisciplinary topic between statistical physics and population biology. The focus is on the phase of quasi-linkage equilibrium (QLE). Our goals here are to clarify under which conditions the QLE phase can be expected to hold in population biology and how the stability of the QLE phase is lost. The QLE state, which has many similarities to a thermal equilibrium state in statistical mechanics, was discovered by M Kimura for a two-locus two-allele model, and was extended and generalized to the global genome scale by Neher & Shraiman (2011). What we will refer to as the Kimura–Neher–Shraiman theory describes a population evolving due to the mutations, recombination, natural selection and possibly genetic drift. A QLE phase exists at sufficiently high recombination rate (r) and/or mutation rates µ with respect to selection strength. We show how in QLE it is possible to infer the epistatic parameters of the fitness function from the knowledge of the (dynamical) distribution of genotypes in a population. We further consider the breakdown of the QLE regime for high enough selection strength. We review recent results for the selection-mutation and selection-recombination dynamics. Finally, we identify and characterize a new phase which we call the non-random coexistence where variability persists in the population without either fixating or disappearing.
Decoding study-independent mind-wandering from EEG using convolutional neural networks
Authors: Jin Christina Yi , Borst Jelmer P , van Vugt Marieke K 
Published: March 2023

Abstract

Objective. Mind-wandering is a mental phenomenon where the internal thought process disengages from the external environment periodically. In the current study, we trained EEG classifiers using convolutional neural networks (CNNs) to track mind-wandering across studies. Approach. We transformed the input from raw EEG to band-frequency information (power), single-trial ERP (stERP) patterns, and connectivity matrices between channels (based on inter-site phase clustering). We trained CNN models for each input type from each EEG channel as the input model for the meta-learner. To verify the generalizability, we used leave-N-participant-out cross-validations (N = 6) and tested the meta-learner on the data from an independent study for across-study predictions. Main results. The current results show limited generalizability across participants and tasks. Nevertheless, our meta-learner trained with the stERPs performed the best among the state-of-the-art neural networks. The mapping of each input model to the output of the meta-learner indicates the importance of each EEG channel. Significance. Our study makes the first attempt to train study-independent mind-wandering classifiers. The results indicate that this remains challenging. The stacking neural network design we used allows an easy inspection of channel importance and feature maps.
The late to early time behaviour of an expanding plasma: hydrodynamisation from exponential asymptotics
Authors: Aniceto Inês , Hasenbichler Daniel , Olde Daalhuis Adri 
Published: March 2023

Abstract
We use exponential asymptotics to match the late time temperature evolution of an expanding conformally invariant fluid to its early time behaviour. We show that the rich divergent transseries asymptotics at late times can be used to interpolate between the two regimes with exponential accuracy using the well-established methods of hyperasymptotics, Borel resummation and transasymptotics. This approach is generic and can be applied to any interpolation problem involving a local asymptotic transseries expansion as well as knowledge of the solution in a second region away from the expansion point. Moreover, we present global analytical properties of the solutions such as analytic approximations to the locations of the square-root branch points, exemplifying how the summed transseries contains within itself information about the observable in regions with different asymptotics.
Connection problem of the first Painlevé transcendents with large initial data
Authors: Long Wen-Gao , Li Yu-Tian 
Published: March 2023

Abstract
In previous work, Bender and Komijani (2015 J. Phys. A: Math. Theor.
48 475202) studied the first Painlevé (PI) equation and showed that the sequence of initial conditions giving rise to separatrix solutions could be asymptotically determined using a

-symmetric Hamiltonian. In the present work, we consider the initial value problem of the PI equation in a more general setting. We show that the initial conditions

(
y
(
0
)
,

y

′

(
0
)
)
=
(
a
,
b
)

located on a sequence of curves

Γ
n

,

n
=
1
,
2
,
…

, will give rise to separatrix solutions. These curves separate the singular and the oscillating solutions of PI. The limiting form equation

b
2

/

4
−

a
3

=

f
n

∼
A

n

6

/

5

for the curves

Γ

n

as

n
→
∞

is derived, where A is a positive constant. The discrete set

{

f
n

}

could be regarded as the nonlinear eigenvalues. Our analytical asymptotic formula of

Γ
n

matches the numerical results remarkably well, even for small n. The main tool is the method of uniform asymptotics introduced by Bassom et al (1998 Arch. Rational Mech. Anal.
143 241–71) in the studies of the second Painlevé (PII) equation.
Study on an air conditioning system with the use of natural cooling
Authors: Izzatillaev J , Axmatova S , Usmonov N , Diyorov R 
Published: March 2023

Abstract
Issues of microclimate mitigation in Uzbekistan during the summer period require urgent resolution. It should be noted that currently there are very few researches, as well as practical recommendations related to the formation of a favorable microclimatic environment in cities with a hot climate. The simplest and most economical way of cooling, in dry and hot climates, is the evaporative cooling of a dry air stream. One of the possible ways to increase the efficiency of the system is the use of night evaporative cooling of water, followed by its accumulation for daytime cooling in heat-insulated batteries. The conducted experiments testify that rather simple and cheap natural sources of cold can be used along with machine cold sources for air conditioning of residential buildings in Uzbekistan.
Change in the structure of the focal spot at the focus of a large solar furnace from the visible angle of the Sun
Authors: Sabirov Y , Makhmudov S , Abdurakhmanov A , Akhmadov Sh , Kholov Sh 
Published: March 2023

Abstract
In this work, for the first time, the coincidence of the proposed theoretical foundations of the methodology for calculating the dimension and energy characteristics of an optical image is shown, in contrast to the previously known to substantiate the separate consideration of the apparent angular size of the Sun 2γ from the accuracy parameters of manufacturing the SCS BLB (γ+Δα). On the example of a comparative assessment of operational measurements with the calculated ones during the past eclipses, where changes in the value of 2γ took place while the value of Δα was constant. These comparative estimates of theoretical and experimental results were carried out during partial solar eclipses that took place on August 1, 2008 and December 26, 2019.
Improving the gravity-vortex micro-hydroelectric power station efficiency by ensuring an acceptable value of the water inlet canal’s twist angle
Authors: Mamadjanov A B , Zakhidov R A , Rakhmatov A , Sharipov F 
Published: March 2023

Abstract
Micro-water energy is a promising alternative energy source that produces electricity in remote areas, separated from the main electricity grid. In this research work, the method of increasing the efficiency of gravity-vortex micro-hydroelectric power station operating in low-pressure water flows through the twist angle of the inlet channel of the basin is presented. Gravity-vortex micro-hydroelectric power station is a new modern green technology as an alternative or renewable energy source. The advantage of this method of electricity production is that it is possible to produce electricity at a low pressure, i.e. starting from a pressure of 0.7 meters. In order to increase the initial speed of the water entering the cylindrical basin, the flow fields of the water flow inside the basin in the range of 0-90 degrees of the inlet channel twist angle were numerically simulated using the ANSYS Fluent software. As a result of the study, the parameters of the influence of the flow velocity vector on the flow field were studied.
Efficiency and environmental indicators of diesel engine operation when using water injection
Authors: Musabekov Z , Ergashev B , Daminov O , Khushnaev O , Kurbanov A , Kukharonok G 
Published: March 2023

Abstract
The indicator diagram of the D-240 diesel engine was built taking into account the data obtained from the calculation of the working process. The construction of the indicator chart was carried out analytically using the Microsoft Excel application package. As a result of mathematical modeling, it was found that at the nominal operating mode of the D-240 diesel engine, the introduction of 30% of water from the cycle supply of diesel fuel into the fuel-air mixture makes it possible to increase the effective power from 55.15 kW to 65.84 kW. The reduction in the specific effective consumption of diesel fuel is 45 gr/(kW/h). The thermal efficiency of the engine under study is 35.57%.
Study on the process automatization of wetting (moistening) the seeds using a step motor
Authors: Denmukhammadiev A , Pardaev A , Kucharov F , Isaev A 
Published: March 2023

Abstract
Researcher Urishev was the first to deal with the issues of mechanization of the process of moistening cotton seeds in the Republic of Uzbekistan. He also developed many devices and mechanisms and proposed methods for conducting experiments on moistening pubescent cotton seeds. However, his works did not address the issues of automation of laboratory facilities. And also Urishev used chemicals for seed treatment, which is harmful to humans and the environment. The creation of an environmentally friendly technology for presowing disinfection of cotton seeds is an urgent task for cotton growing. Research in this field of science has led to the use of electrical energy as the most harmless and cheap means. Along with researchers studying electrical technology in the Republic of Uzbekistan, under the guidance of Professor Mukhammadiev, research work has been carried out since 1985: to develop a non-chemical technology for growing cotton using a spark discharge current, an alternating electric current of industrial frequency. In this article, the possibilities of automating the process of lifting and lowering a laboratory test mechanism for studying the friction of dry and moist cotton seeds proposed by Urishev with the help of a stepper motor were studied in order to automate the process of laboratory experiments. We also obtained equations for finding the resulting force.
Analysis of the methods of diagnosing asynchronous motors according to vibration indicators
Authors: Ibragimov M , Akbarov D , Fayziyev M , Beytullaeva R , Nimatov K , Safarov Kh S 
Published: March 2023

Abstract
Currently, AC motors are in great demand among most modern manufacturing enterprises. Professional experience shows that they use 80% of all electricity generated in the country, so the stability of their work plays an important role in agriculture and industry. Nowadays, vibration diagnostics is one of the effective tools for solving a wide range of problems of detecting defects in electrical machines, preventing parts from failing, extending their service life and increasing their overhaul periods of operation. Preservation of electrical safety, reliability and durability of the operation of electromechanical equipment of electric drives based on asynchronous motors in the production processes of enterprises in the agricultural industry remains an urgent task of electrical systems.
Comparative analysis of noise levels available on simple and rubber granule asphalt-concrete coating roads
Authors: Ismayilov K , Karimova K , Azimov A , Raxmatov U 
Published: March 2023

Abstract
In this article, a scientific study was conducted and studied on the effect of road surface on traffic noise level. The experiment was conducted on two different paved roads and the noise levels were based on international standards. The results of research conducted on asphalt-concrete paved roads with the addition of rubber granules found that the noise levels on high-quality bitumen-paved asphalt concrete paved roads differ from the noise sources. By giving several recommendations for the organization of noise protection have been developed.
Experimental study on traditional timber-concrete hybrid house with different types of roofs using shake table
Authors: Mahmoud M A S A , Lau T L 
Published: March 2023

Abstract
Buildings with different roofing systems possess different seismic performance during earthquake. Most of the traditional buildings are susceptible to earthquake disaster due to no seismic loading is considered in the design. In addition, irregular buildings have been proven to perform badly during earthquake events. Due to lack of investigations on asymmetrical timber-concrete hybrid building under earthquake loading, a ¼ of this type of building model was tested seismically using a unidirectional shake table. Four structural models with frequencies 3.85 Hz, 3.33 Hz, 2.70 Hz and 2.50 Hz varied using diagonal wooden braces and different roof materials namely heavy metal roof and clay roof tile. The models were subjected to El Centro ground motion excitations scaled to 0.08 g, 0.16 g, 0.24 g and 0.32 g PGA resembling 25%, 50%, 75% and 100% of the actual ground motion strength, respectively. Nine accelerometers and seven LVDTs were used to measure the seismic response of the models during shake table test for acceleration and displacement, respectively. Heavier roof material shows a different trend in the amplitudes across the maximum displacement time history, but a clear decrease in acceleration response for the roof level as compared with lighter roof material.
Methods for improving efficiency in cattle farms via innovations in Uzbekistan
Authors: Mamadiyorov D , Mardiev N , Siddikov Z , Toshboev A , Narinbaeva G 
Published: March 2023

Abstract
Our article discusses ways to increase efficiency through the application of innovations in farms specializing in animal husbandry. Livestock is one of the leading sectors of agriculture in Uzbekistan. Meat, dairy and egg products of the population provide the industry with leather, wool and other raw materials. In today’s market economy, one of the most important tasks is to provide the population of Uzbekistan with high quality, environmentally friendly and affordable livestock products. There are many branches of the livestock industry, such as cattle breeding, sheep breeding, poultry farming, horse breeding, fishing, beekeeping. Therefore, the main tasks of the development of these industries are to build a strong fodder base, to provide livestock with a variety of cervitamines, protein-rich, nutritious feeds throughout the year, to properly organize breeding and selection work, based on best practices and scientific achievements such as efficient use, cost-saving new equipment, introduction of innovative efficient technologies, mechanization of production processes, increasing the level of automation, widespread introduction of modern advanced technologies in practice and specialization of farms in formed production and other factors.