bluuebunny/crossref_metadata_2025 huggingface dataset:
Elevated emotion network connectivity is associated with fluctuations in depression
Authors: Kelley Sean W. , Fisher Aaron J. , Lee Chi Tak , Gallagher Eoghan , Hanlon Anna K. , Robertson Ian H. , Gillan Claire M.
Published: October 2023

Elevated emotion network connectivity is thought to leave people vulnerable to become and stay depressed. The mechanism through which this arises is however unclear. Here, we test the idea that the connectivity of emotion networks is associated with more extreme fluctuations in depression over time, rather than necessarily more severe depression. We gathered data from two independent samples of
N
= 155 paid students and
N
= 194 citizen scientists who rated their positive and negative emotions on a smartphone app twice a day and completed a weekly depression questionnaire for 8 wk. We constructed thousands of personalized emotion networks for each participant and tested whether connectivity was associated with severity of depression or its variance over 8 wk. Network connectivity was positively associated with baseline depression severity in citizen scientists, but not paid students. In contrast, 8-wk variance of depression was correlated with network connectivity in both samples. When controlling for depression variance, the association between connectivity and baseline depression severity in citizen scientists was no longer significant. We replicated these findings in an independent community sample (
N
= 519). We conclude that elevated network connectivity is associated with greater variability in depression symptoms. This variability only translates into increased severity in samples where depression is on average low and positively skewed, causing mean and variance to be more strongly correlated. These findings, although correlational, suggest that while emotional network connectivity could predispose individuals to severe depression, it could also be leveraged to bring about therapeutic improvements.
Minorities drive growth resumption in cross-feeding microbial communities
Authors: Micali Gabriele , Hockenberry Alyson M. , Dal Co Alma , Ackermann Martin
Published: October 2023

Microbial communities are fundamental to life on Earth. Different strains within these communities are often connected by a highly connected metabolic network, where the growth of one strain depends on the metabolic activities of other community members. While distributed metabolic functions allow microbes to reduce costs and optimize metabolic pathways, they make them metabolically dependent. Here, we hypothesize that such dependencies can be detrimental in situations where the external conditions change rapidly, as they often do in natural environments. After a shift in external conditions, microbes need to remodel their metabolism, but they can only resume growth once partners on which they depend have also adapted to the new conditions. It is currently not well understood how microbial communities resolve this dilemma and how metabolic interactions are reestablished after an environmental shift. To address this question, we investigated the dynamical responses to environmental perturbation by microbial consortia with distributed anabolic functions. By measuring the regrowth times at the single-cell level in spatially structured communities, we found that metabolic dependencies lead to a growth delay after an environmental shift. However, a minority of cells—those in the immediate neighborhood of their metabolic partners—can regrow quickly and come to numerically dominate the community after the shift. The spatial arrangement of a microbial community is thus a key factor in determining the communities’ ability to maintain metabolic interactions and growth in fluctuating conditions. Our results suggest that environmental fluctuations can limit the emergence of metabolic dependencies between microorganisms.
Impact of the Hunga Tonga volcanic eruption on stratospheric composition
Authors: Wilmouth David M. , Østerstrøm Freja F. , Smith Jessica B. , Anderson James G. , Salawitch Ross J.
Published: October 2023

The explosive eruption of the Hunga Tonga-Hunga Ha’apai (HTHH) volcano on 15 January 2022 injected more water vapor into the stratosphere and to higher altitudes than ever observed in the satellite era. Here, the evolution of the stratospherically injected water vapor is examined as a function of latitude, altitude, and time in the year following the eruption (February to December 2022), and perturbations to stratospheric chemical composition resulting from the increased sulfate aerosols and water vapor are identified and analyzed. The average calculated mass distribution of elevated water vapor between hemispheres is approximately 78% Southern Hemisphere (SH) and 22% Northern Hemisphere in 2022. Significant changes in stratospheric composition following the HTHH eruption are identified using observations from the Aura Microwave Limb Sounder satellite instrument. The dominant features in the monthly mean vertical profiles averaged over 15° latitude ranges are decreases in O
3
(–14%) and HCl (–22%) at SH midlatitudes and increases in ClO (>100%) and HNO
3
(43%) in the tropics, with peak pressure-level perturbations listed. Anomalies in column ozone from 1.2–100 hPa due to the HTHH eruption include widespread O
3
reductions in SH midlatitudes and O
3
increases in the tropics, with peak anomalies in 15° latitude-binned, monthly averages of approximately –7% and +5%, respectively, occurring in austral spring. Using a 3-dimensional chemistry–climate–aerosol model and observational tracer correlations, changes in stratospheric composition are found to be due to both dynamical and chemical factors.
Machine-learning analysis of leadership formation in China to parse the roles of loyalty and institutional norms
Authors: Lee Jonghyuk , Shih Victor C.
Published: October 2023

A thriving cottage industry has long tried to predict the selection outcomes of the Chinese leadership using qualitative judgments based on historical trends and elite interviews. This study contributes to the discourse by adopting machine-learning techniques to quantitatively and systematically evaluate the promotion prospects of Chinese high-ranking officials. By incorporating over 250 individual features of approximately 20,000 high-ranking positions from 1982 to 2020, this paper calculated predicted probabilities of promotion for the 19th Politburo members of the Communist Party of China. The rankings of the promotion probabilities can be used not only to identify candidates who would have traditionally advanced within the party’s promotion norms but also to gauge Xi Jinping’s personal favoritism toward specific individuals. Based on different specifications for positions and periods, we developed measurements to quantify candidates’ levels of perceived loyalty and promotion eligibility. The empirical results demonstrated that the newly formed 20th Politburo Standing Committee was predominantly composed of loyalists who would not have risen to such positions under conventional promotion standards. We further found that, even within his circle of known allies, Xi Jinping did not opt for candidates with strong credentials. The findings of this study underscore the increasing emphasis on loyalty and the diminishing role of institutional norms in China’s high-ranking selections.
Lateral interactions govern self-assembly of the bacterial biofilm matrix protein BslA
Authors: Arnaouteli Sofia , Bamford Natalie C. , Brandani Giovanni B. , Morris Ryan J. , Schor Marieke , Carrington Jamie T. , Hobley Laura , van Aalten Daan M. F. , Stanley-Wall Nicola R. , MacPhee Cait E.
Published: October 2023

The soil bacteriumBacillus subtilisis a model organism to investigate the formation of biofilms, the predominant form of microbial life. The secreted protein BslA self-assembles at the surface of the biofilm to give theB. subtilisbiofilm its characteristic hydrophobicity. To understand the mechanism of BslA self-assembly at interfaces, here we built a molecular model based on the previous BslA crystal structure and the crystal structure of the BslA paralogue YweA that we determined. Our analysis revealed two conserved protein–protein interaction interfaces supporting BslA self-assembly into an infinite 2-dimensional lattice that fits previously determined transmission microscopy images. Molecular dynamics simulations and in vitro protein assays further support our model of BslA elastic film formation, while mutagenesis experiments highlight the importance of the identified interactions for biofilm structure. Based on this knowledge, YweA was engineered to form more stable elastic films and rescue biofilm structure inbslAdeficient strains. These findings shed light on protein film assembly and will inform the development of BslA technologies which range from surface coatings to emulsions in fast-moving consumer goods.
Association neurons in the crow telencephalon link visual signs to numerical values
Authors: Kirschhock Maximilian E. , Nieder Andreas
Published: October 2023

Many animals can associate signs with numerical values and use these signs in a goal-directed way during task performance. However, the neuronal basis of this semantic association has only rarely been investigated, and so far only in primates. How mechanisms of number associations are implemented in the distinctly evolved brains of other animal taxa such as birds is currently unknown. Here, we explored this semantic number-sign mapping by recording single-neuron activity in the crows’ nidopallium caudolaterale (NCL), a brain structure critically involved in avian numerical cognition. Crows were trained to associate visual shapes with varying numbers of items in a number production task. The responses of many NCL neurons during stimulus presentation reflected the numerical values associated with visual shapes in a behaviorally relevant way. Consistent with the crow’s better behavioral performance with signs, neuronal representations of numerical values extracted from shapes were more selective compared to those from dot arrays. The existence of number association neurons in crows points to a phylogenetic preadaptation of the brains of cognitively advanced vertebrates to link visual shapes with numerical meaning.
Wet gas flow metering by combining a vortex flowmeter with disturbance wave frequency
Authors: Li Jinxia , Ding Hongbing , Sun Hongjun , Li Teng
Published: October 2023

Based on a conductance-vortex meter dual-modality system, a novel wet gas flow measurement method is proposed, which combines a vortex meter with disturbance wave frequency. A negative relationship between the vortex signal quality and the disturbance wave frequency is found, on which basis a new segmented fast Fourier transform–continuous wavelet transform vortex frequency extraction method is proposed. Uniform exponential equations are derived for meter over-reading, taking into account the liquid-phase Reynolds and gas-phase Weber numbers, the disturbance wave Strouhal number, density ratio, and the liquid-phase Reynolds number. Finally, a Newton–Armijo-based wet gas metering model is developed by combining these two correlation equations. The percentage errors (PEs) of the gas flow in wet gas are within ±1.0% error bands with uncertainty of 0.56%. The full-scale PEs of liquid flow are within ±10% error bands with uncertainty of 4.71%. The disturbance wave frequency is used to correct the meter over-reading. As no liquid film thickness calibration is needed, the proposed method has low requirements on the conductivity of the medium and hence the application scope of media could be expanded.
High-precision and high-efficiency measurement method of accelerator tunnel control network based on total station angle observation
Authors: Xing Yubo , Dong Lan , Wang Tong , Liang Jing , Ma Na , Wang Xiaolong , Yang Zhen
Published: October 2023

Given the importance of accelerator devices, major developed and emerging countries around the world have invested substantial human and material resources into the development, construction, and operation of more advanced large-scale accelerator devices. High-precision and high-efficiency alignment of the control network is crucial for the stable operation of accelerators. This study proposes a method for measuring tunnel control networks using total station angle observation. By taking advantage of the high precision of angle observation with a total station, we use the measured results of the designed and deployed control points measured by the laser tracker to simulate the total station angle observations, combined with some length scale values in the control network measured by the laser range finder. With the angle observations and several known distances, the point coordinates can be calculated by angle intersection methods. Only angle observations are used from total stations, while different length scale reference conditions are added to constrain the control network. This is done by calculating the point accuracy of the China Spallation Neutron Source circular accelerator. The overall plane point accuracy can reach 66 μm. By using this method, personnel will spend less time on the site and are at lower risk of radiation exposure, for example by automating measurements at night. This method can be used at nighttime for measurements, avoiding the need for daytime work and shielding employees from severe radiation exposure. By employing this method, efficiency can be increased twice. For on-site measurement, it enables monitoring and automated measurement during operation, as well as providing reference for the installation and measurement of tunnel control networks for large scale accelerators such as the Circular Electron Positron Collider.
A Cahn–Hilliard phase field model coupled to an Allen–Cahn model of viscoelasticity at large strains
Authors: Agosti A , Colli P , Garcke H , Rocca E
Published: October 2023

We propose a new Cahn–Hilliard phase field model coupled to incompressible viscoelasticity at large strains, obtained from a diffuse interface mixture model and formulated in the Eulerian configuration. A new kind of diffusive regularization, of Allen–Cahn type, is introduced in the transport equation for the deformation gradient, together with a regularizing interface term depending on the gradient of the deformation gradient in the free energy density of the system. The designed regularization preserves the dissipative structure of the equations. We obtain the global existence of a weak solution in three space dimensions and for generic nonlinear elastic energy densities with polynomial growth, comprising the relevant cases of polyconvex Mooney–Rivlin and Ogden elastic energies. Also, our analysis considers elastic free energy densities which depend on the phase field variable and which can possibly degenerate for some values of the phase field variable. We also propose two kinds of unconditionally energy stable finite element approximations of the model, based on convex splitting ideas and on the use of a scalar auxiliary variable respectively, proving the existence and stability of discrete solutions. We finally report numerical results for different test cases with shape memory alloy type free energy, showing the interplay between phase separation and finite elasticity in determining the topology of stationary states with pure phases characterized by different elastic properties.
Travelling waves and heteroclinic networks in models of spatially-extended cyclic competition
Authors: Groothuizen Dijkema David C , Postlethwaite Claire M
Published: October 2023

Dynamical systems containing heteroclinic cycles and networks can be invoked as models of intransitive competition between three or more species. When populations are assumed to be well-mixed, a system of ordinary differential equations (ODEs) describes the interaction model. Spatially extending these equations with diffusion terms creates a system of partial differential equations which captures both the spatial distribution and mobility of species. In one spatial dimension, travelling wave solutions can be observed, which correspond to periodic orbits in ODEs that describe the system in a steady-state travelling frame of reference. These new ODEs also contain a heteroclinic structure. For three species in cyclic competition, the topology of the heteroclinic cycle in the well-mixed model is preserved in the steady-state travelling frame of reference. We demonstrate that with four species, the heteroclinic cycle which exists in the well-mixed system becomes a heteroclinic network in the travelling frame of reference, with additional heteroclinic orbits connecting equilibria not connected in the original cycle. We find new types of travelling waves which are created in symmetry-breaking bifurcations and destroyed in an orbit flip bifurcation with a cycle between only two species. These new cycles explain the existence of ‘defensive alliances’ observed in previous numerical experiments. We further describe the structure of the heteroclinic network for any number of species, and we conjecture how these results may generalise to systems of any arbitrary number of species in cyclic competition.
On relations between properties in transitive Turing machines
Authors: Torres-Avilés Rodrigo , Gajardo Anahí , Ollinger Nicolas
Published: October 2023

For over two decades, Turing machines (TMs) have been studied as dynamical systems. Several results related to topological properties were established, such as equicontinuity, periodicity, mortality, and entropy. There are two main topological models for TMs, and these properties strongly depend on the considered model. Here, we focus on transitivity, minimality and other related properties. In the context of TMs, transitivity refers to the existence of a configuration whose evolution contains every possible pattern over any finite window. Minimality means that every configuration fulfills the aforementioned statement, which strongly restricts TM behaviour. This paper establishes relations between the following properties: transitivity, minimality, the existence of blocking words, aperiodicity and reversibility. It also explores some properties of the embedding technique, which combines two TMs to produce a third. This technique has been used in previous works to prove the undecidability of several dynamical properties. Here, we demonstrate its power and versatility and how the produced machine, under a few particular conditions, will inherit the properties of one of the original machines.
Finite switching near heteroclinic networks
Authors: Castro S B S D , Garrido-da-Silva L
Published: October 2023

We address the level of complexity that can be observed in the dynamics near a robust heteroclinic network. We show that infinite switching, which is a path towards chaos, does not exist near a heteroclinic network such that the eigenvalues of the Jacobian matrix at each node are all real. Furthermore, for a path starting at a node that belongs to more than one heteroclinic cycle, we find a bound for the number of such nodes that can exist in any such path. This constricted dynamics is in stark contrast with examples in the literature of heteroclinic networks such that the eigenvalues of the Jacobian matrix at one node are complex.
Deep learning based MLC aperture and monitor unit prediction as a warm start for breast VMAT optimisation
Authors: Vandewinckele L , Reynders T , Weltens C , Maes F , Crijns W
Published: October 2023

Objective. Automated treatment planning today is focussed on non-exact, two-step procedures. Firstly, dose–volume histograms (DVHs) or 3D dose distributions are predicted from the patient anatomy. Secondly, these are converted in multi-leaf collimator (MLC) apertures and monitor units (MUs) using a generic optimisation to obtain the final treatment plan. In contrast, we present a method to predict volumetric modulated arc therapy (VMAT) MLC apertures and MUs directly from patient anatomy using deep learning. The predicted plan is then provided as initialisation to the optimiser for fine-tuning. Approach. 148 patients (training: 101; validation: 23; test: 24), treated for right breast cancer, are replanned to obtain a homogeneous database of 3-arc VMAT plans (PTVBreast: 45.57 Gy; PTVBoost: 55.86 Gy) according to the clinical protocol, using RapidPlanTM with automatic optimisation and extended convergence mode (clinical workflow). Projections of the CT and contours are created along the beam’s eye view of all control points and given as input to a U-net type convolutional neural networks (CNN). The output are the MLC aperture and MU for all control points, from which a DICOM RTplan is built. This is imported and further optimised in the treatment planning system using automatic optimisation without convergence mode, with clinical PTV objectives and organs-at-risk (OAR) objectives based on the DVHs calculated from the imported plan (CNN workflow). Main results. Mean dose differences between the clinical and CNN workflow over the test set are 0.2 ± 0.5 Gy at D
95% and 0.6 ± 0.4 Gy at D
0.035cc of PTVBreast and −0.4 ± 0.3 Gy at D
95% and 0.7 ± 0.3 Gy at D
0.035cc of PTVBoost. For the OAR, they are −0.2 ± 0.2 Gy for D
mean,heart and 0.04 ± 0.8 Gy for D
mean,ipsilateral lung. The mean computation time is 60 and 25 min respectively. Significance. VMAT optimisation can be initialised by MLC apertures and MUs, directly predicted from patient anatomy using a CNN, reducing planning time with more than half while maintaining clinically acceptable plans. This procedure puts the planner in a supervising role over an AI-based treatment planning workflow.
The Precursor of GRB211211A: A Tide-induced Giant Quake?
Authors: Zhou Enping , Gao Yong , Zhou Yurui , Lai Xiaoyu , Shao Lijing , Wang Weiyang , Xiong Shaolin , Xu Renxin , Yi Shuxu , Yim Garvin , Yue Han , Zhang Zhen
Published: October 2023

The equilibrium configuration of a solid strange star in the final inspiral phase with another compact object is generally discussed, and the starquake-related issue is revisited, for a special purpose to understand the precursor emission of binary compact star merger events (e.g., that of GRB211211A). As the binary system inspirals inward due to gravitational wave radiation, the ellipticity of the solid strangeon star increases due to the growing tidal field of its compact companion. Elastic energy is hence accumulated during the inspiral stage which might trigger a starquake before the merger when the energy exceeds a critical value. The energy released during such starquakes is calculated and compared to the precursor observation of GRB211211A. The result shows that the energy might be insufficient for binary strangeon-star case unless the entire solid strangeon star shatters, and hence favors a black hole-strangeon star scenario for GRB211211A. The timescale of the precursor as well as the frequency of the observed quasi-periodic-oscillation have also been discussed in the starquake model.
Disturbance Observer-based Pointing Control of Leighton Chajnantor Telescope
Authors: Chen Weirui , Wang Zheng
Published: October 2023

Leighton Chajnantor Telescope (LCT), i.e., the former Caltech Submillimeter Observatory telescope, will be refurbished at the new site in Chajnantor Plateau, Chile in 2023. The environment of LCT will change significantly after its relocation, and the telescope will be exposed to large wind disturbances directly because its enclosure will be completely open during observation. The wind disturbance is expected to be a challenge for LCT’s pointing control since the existing control method cannot reject this disturbance very well. Therefore, it is very necessary to develop a new pointing control method with good capability of disturbance rejection. In this research, a disturbance observer—based composite position controller (DOB-CPC) is designed, in which an H∞ feedback controller is employed to compress the disturbance, and a feedforward linear quadratic regulator is employed to compensate the disturbance precisely based on the estimated disturbance signal. Moreover, a controller switching policy is adopted, which applies the proportional controller to the transient process to achieve a quick response and applies the DOB-CPC to the steady state to achieve a small position error. Numerical experiments are conducted to verify the good performance of the proposed pointing controller (i.e., DOB-CPC) for rejecting the disturbance acting on LCT.
Technical Feasibility Study for Development of Reference Material for Nitrate in Meat Product
Authors: de Oliveira M C , de Almeida M D , Osorio A C P , de Sena R C , Souza V
Published: October 2023

Nitrate measurement is a fundamental part of quality control in the meat products industries. Ensuring the technical validity of the results of these measurements can be achieved through the adoption of appropriate metrological tools such as reference materials. The technical feasibility for producing a nitrate reference material in a meat product was evaluated by preparing a batch of material on a small scale. The adequacy of the preparation procedure was evaluated by means of pertinent physicochemical and microbiological measurements. A batch of 175 units containing approximately 5 g of lyophilized cooked ham in each package was produced. The batch was submitted to preliminary studies to assess homogeneity and stability under transport conditions, in accordance with ISO 17034 and the applicable ISO guides.
A method to extend the calibration beyond the defined periodicity
Authors: Miqueleti S A , Costa-Félix R P
Published: October 2023

The assignment of calibration intervals shall be a formal process based on the results of previous calibrations. With the coronavirus pandemic, one means to avoid a non-conformity instrument and ensure an updated calibration program is to extend the calibration interval of laboratories equipment. The ILAC-G24 has published guidelines for that purpose. What can be done if an extension on the calibration validity is further than previously defined? This article presents a way to increase instrument uncertainty and extend the calibration period based on ISO Guide 35, applying a trend analysis and stability criteria of the reference material properties to the case of a measurement system.
Assessment of glycerol in biodiesel using an ultrasonic measurement method
Authors: Oliveira P A , Baesso R M , Alvarenga A V , Costa-Felix R P B
Published: October 2023

Biodiesel is a renewable fuel, biodegradable and alternative to diesel oil consisting chemically of fatty acid alkyl esters and obtained by the transesterification reaction. After transesterification, undesirable components may remain in biodiesel. The presence of these components negatively influences the properties and performance of biodiesel. This research aims to evaluate biodiesel quality, using the quantitative ultrasound technique to determine the presence of the contaminant glycerol in biodiesel samples. The blends used in this study consisted of biodiesel and glycerol varying from 0 % to 0.5 % of glycerol by mass. The measurement uncertainty was evaluated according to the Guide to the Expression of Uncertainty in Measurement. The speed of sound in biodiesel/glycerol blends was measured by the pulse-echo technique (@ 5 MHz) and was considered equivalent for the different concentrations studied. The maximum measurement uncertainty obtained was 2.2 m·s−1 (0.16 %).
Proposition of water meter for buildings based on a thin-film resistive sensor: electromechanical and thermal characterizations
Authors: Gonçalves L S , Medeiros K A R , Barbosa C R H
Published: October 2023

Notoriously, measurement proves to be essential to encourage water conservation. Thus, this work characterizes two thin-film resistive sensors (bend sensors) with different coatings aiming at their application to measure water consumption. For this, the individual water measurement system is presented and discussed briefly. Then, resistive sensor parameters and operating principles are detailed, as well as the mathematical formulation of the correlation of the sensor resistance with the flow velocity. Methodologically, the system developed for the electromechanical and thermal characterization of the sensor is presented. The results allowed obtaining a quadratic relationship between the sensor deflection angle and the resistance. Furthermore, it was observed that the polyester-coated sensor presented a low hysteresis value when subjected to temperature variation, obtaining a negative linear relationship between the sensor resistance and temperature. In turn, the polyimide-coated sensor did not show low hysteresis when exposed to temperature change and flexed at 50° and 70° angles. Finally, it is proposed for future work computer simulations and experimental tests to confirm the applicability of the sensor for water measurement.
Study on the reproducibility of the ice point realization at the Thermometry Laboratory of Inmetro
Authors: Pereira Neto M A , Diniz P H F , Torres A G , Oliveira A R , Quelhas K N
Published: October 2023

Despite being classified today as a secondary reference point of temperature, the ice point (0.0 °C) is still very important in many thermometry applications due to its simplicity, effectiveness, reproducibility and low cost. Uncertainties as low as some hundreds of microkelvin can be achieved, but it depends on the level of care of the experimental procedure practiced by the laboratory. The Thermometry Laboratory of Inmetro (Later) has adopted for a long time a conservative value available in literature for the uncertainty of the ice point. In order to reach more realistic results, in line with the specific equipment and experimental procedure of the lab, a study on the reproducibility of the ice point realization was conducted, enabling a significant reduction of the uncertainty previously adopted. In addition, from the uncertainty analysis performed, it was possible to show the great importance of the standardization of the ice bath preparation procedure for the achievement of better results.
The importance of proper storage of agar phantom on the water-glycerol-benzalkonium chloride mixture to maintain the ultrasonic group velocity
Authors: Souza R M , Costa-Félix R P B , Alvarenga A V
Published: October 2023

The present paper studied the metrological impact on the ultrasound group velocity in not storing the agar phantoms in the water-glycerol-benzalkonium chloride maintenance mixture. The ultrasonic velocity and the phantom’s thickness were measured by the pulse-echo technique seven times within 44 days, whereas four replicates were carried out under repeatability conditions. The phantom’s thickness did not differ statistically along the days since the normalized error was less than 1.0. Based on the results obtained, one can conclude that the ultrasound group velocity decreased in a logarithmic function along the days.
Validation of a Bovine Viral Diarrhea Virus (BVDV) absolute quantification method by digital droplet PCR (ddPCR).
Authors: Henrique M R F , Ramos-Júnior J L P , Flatschart R B , Barroso S P C , Heinemann M B , da Fonseca F G , Granjeiro J M , de Souza V , Folgueras-Flatchart A V
Published: October 2023

A increasingly common way for the diagnostics of viral agents is to carry out PCR from biological samples, which can detect their nucleic acid during the acute phase of the disease. Taking into account the need for quality control of PCR tests in laboratories accredited by ISO/IEC 17025:2017, we intend to carry out feasibility studies for the production of Reference Materials (MR) for these molecular tests, using BVDV in the matrix serum as a model. The first step for this goal was the validation of an analytical method for quantification of viral RNA to characterize the material under study. Primers and probe from a commercial qualitative assay kit designed for Real Time RT-PCR (VetMax Gold BVDV - Thermo Fisher) were used for quantification of BVDV by ddPCR. The technique was optimized and a Detection Limit of 13 copies/μL was determined, allowing a Quantification Limit of 38 copies/μL. The method showed to be linear over two orders of magnitude. The method will be used in the homogeneity study and long-term stability tests for the pilot batch of BVDV in Fetal Bovine Serum MR, a model for the production of MR intended for PCR of BVDV and other Flaviviridae.
Digital enhancement of OCT images toward better diagnostic of precursor cancer lesions in the uterine colon
Authors: Malinovski I , Couceiro I B , Alvarenga A D , Cordes A H , de Andrade C V , Russomano F B , von der Weid J P
Published: October 2023

We present a combination of image processing operations, which improve the quality of OCT images. The sequence is: (1) Gaussian blur, (2) Enhance Local Contrast (CLAHE), (3) FFT based band-pass filter, (4) Background Subtraction, (5) adjustment of the contrast of the image with light saturation (Enhance Contrast) and finally (6) reassignment of the palette such as to enhance the bright part of the images. The multi-step treatment reduces pixel-to-pixel noise, improves the homogeneity of the contrast, supresses vertical strips, reduces cosmetic distractions, equalizes contrast across a collection of images, and uses the pallet to emphasise areas of greater intensity. The enhanced images show a significant improvement in their quality, with details that do not appear in the original OCT image. The processing of these images and the comparison with untreated OCT images are shown throughout the paper.
Glass campanula effects on measurement results in high capacity mass comparator
Authors: Beatrici A.
Published: October 2023

The calibrations or checking of mass standards with nominal values greater than 10 kg and high accuracy class require special attention to the environmental conditions stability due to the their volume. The equipment used to calibrate this kind of mass standards usually has a weighing chamber (in this case a glass campanula or bell jar) to avoid, at least to reduce, the effects of environmental changes. In this study will be present the effects of these weighing campanulas on the standard deviations and in mass measurements results using only the internal tare (without weights in the balance plate) and using two 10 kg test weights.
Inmetro’s participation in SIM kilogram dissemination project (SKDP) Mass stability analysis of the SIM21 mass standard (1 kg) over three years in the SIM Kilogram Dissemination Project (SKDP)
Authors: Cacais F L , Loayza V M , Beatrici A , Quintão D , Rebelo A S
Published: October 2023

Inmetro’s mass laboratory (Lamas) participated in SIM Kilogram Dissemination Project (SKDP). The assessment of mass stability of the SIM21 1 kg stainless steel mass standard was carried out between 2018 and 2021. The results show a typical variability for a weighing system but not clear trend in measurements. Therefore one can say no mass drift for SIM21 mass standard was observed along this period.
A software to calibrate low-current meters in the range of picoamperes to microamperes
Authors: Pinto M V V , Ventura R V F , Landim R P , David R P
Published: October 2023

Among the main pillars of industry 4.0 are big data, artificial intelligence, and the industrial internet of things (IIoT) which, together with industrial automation, allow for significant operational advances. In the field of calibration, where processes and procedures must be standardized, automation diminishes the variability caused by human intervention. In addition, the process is no longer limited to the time the technician is present, speeding up deliveries and improving laboratory efficiency and productivity. In this work, a software for the calibration of low current meters is presented. Also, a mathematical model and uncertainty analysis related to the adopted calibration method is presented. It was possible to calibrate an electrometer in a fully automated way, with minimal intervention by the technician. This software was successfully validated through an intralaboratory comparison.
Bilateral comparison of dc voltage at 10 V between UTE and INMETRO
Authors: Slomovitz D , Landim R P , de Souza H , Trigo L
Published: October 2023

A bilateral comparison between the Instituto Nacional de Metrologia, Qualidade e Tecnología (INMETRO) and the Administración Nacional de Usinas y Trasmisiones Eléctricas (UTE) was performed during 2019 and 2020. The National Laboratory Standards used were two Josephson Voltage Standards at INMETRO (a CJVS and a PJVS), and a bank of multiple Zeners at UTE, both at 10 V level. The traveling standards were two commercial Zener based sources. The INMETRO was the pilot laboratory and the comparison error was (-1.79 ± 2.55) parts in 107, k=2.
Development of an upgraded E-field strength probe to be used as a transfer standard for metrological proposes
Authors: Mateus Sánchez Juan C. , Meng Donglin
Published: October 2023

This paper describes the development of an E-field strength sensor probe based on schottky diode technology to be used as a transfer standard for metrological proposes. This sensor probe was designed in a joint project between the National Metrology Institutes of Brazil (Inmetro) and China (NIM China) to bring traceability to many facilities generating E-field strength of both Institutes. The developed sensor allows transferring the E-field traceability from a μ-TEM Cell used as a primary standard to secondary standards like TEM and G-TEM Cells in the frequency range of 500 kHz to 2 GHz and at E-field intensities from 3 V/m to 70 V/m, with low uncertainty and a good dynamic range. The working principle of the new measuring system is similar to an old system that is not manufactured anymore, but it was re-designed in order to improve its performance and characteristics obtaining, as a result, a reduction in size of more than 10 times. Stability test results are also presented, showing that the new sensor is suitable for future inter-comparisons.
Review on Drone application methodologies in agriculture precision
Authors: Wadod Mohammed M. , Mohammed Faisel G.
Published: October 2023

In recent times, Drone use has increased significantly in the field of precise agriculture. These aircraft, which are equipped with thermal and multi-spectrum cameras, allow us to increase agricultural production in proportion to the increasing demand of the population and monitor crops grown in large areas, which is a very difficult task given the large areas of fields and the standards required for the successful cultivation of the crop in terms of soil moisture and fertility, proximity to water sources, and the possibility of its delivery In a way that reduces the waste of this water. Fields are at risk of crop damage due to diseases to crops caused by insects and pests, as drones can be used to spray pesticides and fertilizers in a way that reduces the health risks to people when spreading them manually. In this research paper, we will address several previous research related to the use of sensor and drone techniques in the field of precision agriculture and their efficiency in helping to sustain production and increase crop yields.
Principal Component Analysis of Selective Bands for Digital Satellite Imagery Classification
Authors: Al-Ani Laith A. , Mohammed Alyaa H.
Published: October 2023

Principal Component Analysis technique was applied to correlated multispectral data to convert it into uncorrelated data for the purpose of benefiting from its use in the automatic classification process.This project aims to classify multispectral satellite images using selective thematic Mapper (TM) spectral bands, and principal component (PC) images. The supervised classification method with maximum likelihood is adopted to perform the classification process.This technique was implemented using banding images and PC’s images. The results showed that the classification accuracy of the three spectral bands with the highest contrast was 86.9%, compared to the classification accuracy of the first three PC’s (89.08%). This value represents the highest classification accuracy obtained among the classification accuracy values for the spectral bands or PC images alone or in combination.

The results show the advantages of feature selection in the PC’s, for every value of n-components, the 1stprincipal is the best choice. Moreover at low values of n-PC’s contain more information about the discriminability of classes than for any combination of n-original spectral channels.
The Quantitative Morphometric Analysis of the Biggest Basin in Western Plateau of Iraq
Authors: Mohammed Maryam J. , Jawad Laith A.
Published: October 2023

The integrative utilization of the remotely sensed extracted data with geographic information system analyzing capabilities is the optimal approach to determine the shape of rivers and valleys basins realistically and to know their morphological and geomorphological characteristics, so it gives an accurate perception of ways to exploit surface or groundwater resources for these basins.

The concerned region is the western plateau which located between (38° 45’ 31˝) and (48° 17’ 12.58) eastern longitudes; (34 ° 30’ 10.77) and (29 0’ 38) northern latitudes. The hydrological analysis based on the geographic information system of the region basins showed that the Houran valley basin is the largest basin in the western plateau that described as a fourth-order drain basin that has dendritically and sometimes paralleled drain network.

The quantitative analysis of the morphological features showed that longitudinal drain density was 0.1698 km / km2, which reflects a soil quality with high permeability plus a desert climate of arid to semi-arid weather. The circulation ratio is 0.08566, which indicates that the basin is in an early geomorphological stage and that the linear structures control the pattern of its drainage network. The elongation ratio is 0.112, which means that there are significant differences in the hardness of its geological structure, and this would help the use of groundwater in the process of sustainable development of the region. The adoption of quantitative methods based on spatial analysis in hydrological studies supports the optimal use of water resources (from accurate identification of dam sites to realistic planning of irrigation projects), especially in areas with scarce water.
Evaluation the spectral reflectivity of Baghdad city for different bands using R.S and GIS techniques on December 2021
Authors: Hassan Eman S. , Hasson Ahmed F. , Khanjer Ebtesam F.
Published: October 2023

The rapid advancement of remote sensing technology in recent years has made it easier to observe and study the Earth’s surface with greater precision. Satellite remote sensors have poor spatial accuracy and cannot provide accurate details of targets on the Earth’s surface. As a result, spectral accuracy is required to determine target details such as water, vegetation and soil types. Because of the differences in spectral reflectivity, these materials can be distinguished. The amount of randomly incident sunlight scattered on the Earth’s surface at a given wavelength is reflected in spectral reflection with different wavelengths. The amount of light reflected on the Earth’s surface varies, the spectral reflectivity is defined as the ratio of the spectral intensity of the reflected light to the incident light. In this study, 51 locations in downtown Baghdad were chosen for four different types of land cover (water bodies, farms, open areas, and residential areas), and their spectral reflectance was calculated on three different bands (RED, NIR and SWIR) for December 2021. The spectral reflectance was calculated using a mathematical equation using Sentinel 2 satellite images that had been processed and analyzed.
Study of the Deterioration in the Vegetation Cover of Al-Amiriya Region in Baghdad Province by using PCA equation on the Satellite Image
Authors: Hamdi Halah Qahtan , Sabeeh Al-Hassany Gheidaa
Published: October 2023

This paper examines the decrease in vegetation cover in Al-Amiriya from 2007 to 2020. Using two Landsat satellite multispectral images and Principal Components Analysis (PCA) with a classification technique, the overall vegetation cover in the city was determined. Results show a decrease in overall green land when comparing the two images. The ArcMap-GIS program was used to conduct the study, and the results showed that the overall vegetation cover ratio had decreased from 32.53% in 2007 to 31.29% in 2020. This means that there has been a decrease in vegetation cover over the past 13 years. It is important to note that this could be a sign of environmental degradation and increased human development in the area, and should be taken into consideration when developing strategies to protect the environment.
First and Second-Order Polynomial Transformation for satellite image correction
Authors: Hamdi Halah Qahtan
Published: October 2023

The absence of ground control points (GCPs) in historical declassified intelligence satellite photography (DISP) images, as well as satellite orbit parameters, and camera interior and exterior orientation parameters, necessitated the creation of a first-order 1st polynomial equation model and a second-order 2nd polynomial equation model for orthorectification purposes. The Mosul region of northwest Iraq was used as a case study, with data from Satellite 7 released on April 15, 1999. The study achieved an RMS of approximately 2.1 x 10−8 and the error ratio was considered acceptable due to the 30-meter resolution of the satellite image.
Toward the Safe City Index Development: Infrastructure Security Indicators
Authors: Al-Hilli Ammar Mohammed Abdulmajeed , Al-Alwan Hoda A. S.
Published: October 2023

Cities all over the world are suffering from various and multiple problems and crises that are estimated to increase if there are no practical and realistic solutions that reflect the real needs of the city. These solutions should be able to predict future challenges, despite the cities’ struggle to improve and enhance their economic, social, environmental, and security goals besides the strategies necessary to achieve them. Accordingly, many concepts have emerged to find solutions that help cities to overcome the challenges they face. Among these are the concepts of the resilient city, the safe city, the smart city, etc. Each concept has established its own index that provided a vision of how to solve problems and face challenges and crises in order to develop the city. Nevertheless, big gaps have appeared in cities with the spread of unpredicted challenges and threats inside them,. Accordingly, the cities’ authorities and local communities are obligated to comprehend how their cities are performing, where advancement is being made, or where failure appears in their systems after-shocks. The research seeks to develop the “infrastructure security pillar” within the safe city index, in particular. This is achieved through a thorough reviewing and crisscrossing of the infrastructure indicators in the safe, resilient, and smart city indexes. The research concludes subdivisions to the infrastructure security pillar presented by Ecosystem, Transportation, Energy, Water & sewage, Disasters & threats, and Security system. Each has its own extracted indicators based on the intersection of existing ones, as well as the modification and addition of others. This development helps to achieve integration between the prevailing concepts towards a safer city performance. This development can be used to assess safety parameters in existing cities.