bluuebunny/crossref_metadata_2025 huggingface dataset:
Thyroid Profile of Childhood Tuberculosis Treated with Anti Tuberculosis Drug During Intensive Phase
Authors: Anam Moh Syarofil , Mahmudah Mahmudah , Cayami Ferdy K , Mexitalia Maria , Sidhartani Magdalena , Subagio Hertanto Wahyu , Utari Agustini
Published: April 2023

Background: Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis.  The incidence is  10 % in children. Tuberculosis has high morbidity and mortality which needs adequate treatment. The side effects of FDC is thyroid hormone dysfunction which can interfere children's quality of life. However, research about the effect of FDC therapy on thyroid hormone profile in children with TB are very limited. Objective: To determine the effect of anti-tuberculosis drug treatment on thyroid hormone profile in paediatric tuberculosis. Methods: A one group pretest-posttest design study of 50 patients was conducted at the Semarang Health Center for the period January 2021-June 2021. Thyroid function tests of TSH, FT4 and T3, in TB children were measured before FDC therapy and 2 months after administration. The data were analysed descriptively and a comparative test was performed using SPSS 25.Results: There were no significant differences in TSH, FT4 and T3 serum levels before FDC therapy and 2 months of FDC administration. Thyroid hormone levels before treatment and 2 months after administration of FDC, respectively, euthyroid in 44 vs 42 patients.Conclusion: Two months of tuberculosis treatment in children decreased the serum FT4 and T3 level but no changes in the serum TSH level before and after the treatment.
Cigarette Smoke Exposure, but Not High Fat Diet, is Able to Induce Atherosclerosis in Wild-Type Rats
Authors: Amanda Qorry , Widyastiti Nyoman Suci , Prajoko Yan Wisnu , Maharani Nani , Bahrudin Udin
Published: April 2023

Background: High-fat diet (HFD) and cigarette smoke exposure (CSE) have been used to induce atherosclerosis in wild-type (WT) rats however, their effectivity remains unclear.Objective: To confirm and compare the effectivity of HFD and CSE on both the histopathology of aorta and the level of malondialdehyde (MDA) in WT rats.Methods: Thirty-six WT Wistar rats were divided into four main groups (K0, K1, K2, and K3) and four subgroups (K3A, K3B, K3C, and K3D). The negative control group (K0) was fed with regular diet. Group K1 was treated with an intravenous adrenaline followed by high-fat diet (HFD), K2 was fed with regular diet and given CSE, while K3 was treated with a combination of CSE and HFD. The serum and cardiac MDA levels were measured using ELISA. Hematoxylin eosin and oil red O staining of aorta were done for measuring of the intima-media thickness (IMT) ratio and for counting of foam cells, respectively. Results: Both serum and cardiac tissue MDA levels in either K1, K2, or K3 were significant higher (p<0.01) than that of in K0. IMT ratio in K3 was significant higher compared to other groups (p<0.01). Foam cell numbers were significant higher in K2 and K3 groups than that of in either K0 or K1 (p<0.01).Conclusion: While the HFD fails to induce atherosclerosis in WT rats for 28 days, either CSE or combination of CSE and HFD is able to induce it, and the combination is better than alone.
Establishing quality indicators for point of care glucose testing: recommendations from the Canadian Society for Clinical Chemists Point of Care Testing and Quality Indicators Special Interest Groups
Authors: Shaw Julie L.V. , Arnoldo Saranya , Beach Lori , Bouhtiauy Ihssan , Brinc Davor , Brun Miranda , Collier Christine , Kostantin Elie , Fung Angela W.S. , Füzéry Anna K. , Huang Yun , Kaur Sukhbir , Knauer Michael , Labrecque Lyne , Leung Felix , Shea Jennifer L. , Thakur Vinita , Thorlacius Laurel , Venner Allison A. , Yip Paul M. , De Guire Vincent
Published: April 2023

Objectives

Monitoring quality indicators (QIs) is an important part of laboratory quality assurance (QA). Here, the Canadian Society of Clinical Chemists (CSCC) Point of Care Testing (POCT) and QI Special Interest Groups describe a process for establishing and monitoring QIs for POCT glucose testing.

Methods

Key, error prone steps in the POCT glucose testing process were collaboratively mapped out, followed by risk assessment for each step. Steps with the highest risk and ability to detect a non-conformance were chosen for follow-up. These were positive patient identification (PPID) and repeat of critically high glucose measurements. Participating sites were asked to submit aggregate data for these indicators from their site(s) for a one-month period. The PPID QI was also included as part of a national QI monitoring program for which fifty-seven sites submitted data.

Results

The percentage of POCT glucose tests performed without valid PPID ranged from 0–87%. Sites without Admission-Discharge-Transfer (ADT) connectivity to POCT meters were among those with the highest percentage of POCT glucose tests performed without valid PPID. The percentage repeated critically high glucose measurements ranged from 0–50%, indicating low compliance with this recommendation. A high rate of discordance was also noted when critically high POCT glucose measurements were repeated, demonstrating the importance of repeat testing prior to insulin administration.

Conclusions

Here, a process for establishing these QIs is described, with preliminary data for two QIs chosen from this process. The findings demonstrate the importance of QIs for identification and comparative performance monitoring of non-conformances to improve POCT quality.
Accidental ingestion of jimsonweed by an adolescent
Authors: Forno Francis J. , Terry Richard A.
Published: April 2023

Ingestion of jimsonweed can result in hallucinations. Despite this side effect, the differential diagnosis of jimsonweed toxicity can be difficult, in part, because routine drug screens do not detect this agent. Such a delay in diagnosis not only postpones treatment but may also result in the patient’s death. Treatment involves gastric lavage, followed by supportive care. Life-threatening cases entail the cautious use of physostigmine salicylate.
Systolic blood pressure in acute ischemic stroke and impact on clinical outcomes
Authors: Wallen Michelle , Banerjee Paul , Webb-McAdams Amanda , Mirajkar Amber , Stead Tej , Ganti Latha
Published: April 2023

Context

Stroke is one of the largest healthcare burdens in the United States and globally. It continues to be one of the leading causes of morbidity and mortality. Patients with acute ischemic stroke (AIS) often present with elevated blood pressure (BP).

Objectives

The objective of our study was to evaluate the association of systolic blood pressure (SBP) in the emergency department (ED) with stroke severity in patients with AIS.

Methods

This observational study was conducted at an ED with an annual census of 80,000 visits, approximately half (400) of which are for AIS. The cohort consisted of adult patients who presented to the ED within 24 h of stroke symptom onset. BP was measured at triage by a nurse blinded to the study. Stroke severity was measured utilizing the National Institutes of Health Stroke Scale (NIHSS). Statistical analyses were performed utilizing JMP 14.0. This study was approved by our medical school’s institutional review board.

Results

Patients with higher SBP had significantly lower NIHSS scores (p=0.0038). This association was significant even after adjusting for age and gender. By contrast, diastolic blood pressure (DBP) did not appear to impact stroke severity. There was no difference in the DBP values between men and women. Higher SBP was also significantly associated with being discharged home as well as being less likely to die in the hospital or discharged to hospice. The DBP did not demonstrate this association. Neither the SDP nor the DBP were significantly associated with the hospital length of stay (LOS). In multivariate models that included age, gender, basal metabolic index (BMI), comorbidities, and ED presentation, elevated SBP was associated with better prognosis.

Conclusions

In this cohort of patients presenting with stroke-like symptoms to the ED, higher SBP was associated with lower stroke severity and higher rates of being discharged to home rather than hospice or death.
Loss of renal tubular G9a benefits acute kidney injury by lowering focal lipid accumulation via CES1
Authors: Yang Dong , Fan Yu , Xiong Mingrui , Chen Yuchen , Zhou Yihao , Liu Xikai , Yuan Yangmian , Wang Qing , Zhang Yu , Petersen Robert B , Su Hua , Yue Junqiu , Zhang Chun , Chen Hong , Huang Kun , Zheng Ling
Published: April 2023

Surgery‐induced renal ischemia and reperfusion (I/R) injury and nephrotoxic drugs like cisplatin can cause acute kidney injury (AKI), for which there is no effective therapy. Lipid accumulation is evident following AKI in renal tubules although the mechanisms and pathological effects are unclear. Here, we report that Ehmt2‐encoded histone methyltransferase G9a is upregulated in patients and mouse kidneys after AKI. Renal tubular specific knockout of G9a (Ehmt2Ksp) or pharmacological inhibition of G9a alleviates lipid accumulation associated with AKI. Mechanistically, G9a suppresses transcription of the lipolytic enzyme Ces1; moreover, G9a and farnesoid X receptor (FXR) competitively bind to the same promoter regions of Ces1. Ces1 is consistently observed to be downregulated in the kidney of AKI patients. Pharmacological inhibition of Ces1 increases lipid accumulation, exacerbates renal I/R‐injury and eliminates the beneficial effects on AKI observed in Ehmt2Ksp mice. Furthermore, lipid‐lowering atorvastatin and an FXR agonist alleviate AKI by activating Ces1 and reducing renal lipid accumulation. Together, our results reveal a G9a/FXR‐Ces1 axis that affects the AKI outcome via regulating renal lipid accumulation.
Tissue‐like environments shape functional interactions of HIV‐1 with immature dendritic cells
Authors: Gallucci Lara , Abele Tobias , Fronza Raffaele , Stolp Bettina , Laketa Vibor , Sid Ahmed Samy , Flemming Annica , Müller Barbara , Göpfrich Kerstin , Fackler Oliver T
Published: April 2023

Immature dendritic cells (iDCs) migrate in microenvironments with distinct cell and extracellular matrix densities in vivo and contribute to HIV‐1 dissemination and mounting of antiviral immune responses. Here, we find that, compared to standard 2D suspension cultures, 3D collagen as tissue‐like environment alters iDC properties and their response to HIV‐1 infection. iDCs adopt an elongated morphology with increased deformability in 3D collagen at unaltered activation, differentiation, cytokine secretion, or responsiveness to LPS. While 3D collagen reduces HIV‐1 particle uptake by iDCs, fusion efficiency is increased to elevate productive infection rates due to elevated cell surface exposure of the HIV‐1‐binding receptor DC‐SIGN. In contrast, 3D collagen reduces HIV transfer to CD4 T cells from iDCs. iDC adaptations to 3D collagen include increased pro‐inflammatory cytokine production and reduced antiviral gene expression in response to HIV‐1 infection. Adhesion to a 2D collagen matrix is sufficient to increase iDC deformability, DC‐SIGN exposure, and permissivity to HIV‐1 infection. Thus, mechano‐physical cues of 2D and 3D tissue‐like collagen environments regulate iDC function and shape divergent roles during HIV‐1 infection.
¿Intensificación? en el aprovechamiento de aves entre los cazadores-recolectores-pescadores de la región del canal Beagle
Authors: Tivoli Angélica Montserrat
Published: April 2023

Se discute aquí el carácter de los procesos de cambio relativos al aprovechamiento de aves en la región del canal Beagle que tuvieron lugar en momentos recientes de la secuencia de ocupación (a partir de aproximadamente 1500 años AP). Se ha señalado la existencia de un proceso de intensificación vinculado a la pesca hacia momentos tardíos, mientras que con respecto a la explotación de aves se halló una reorientación en su aprovisionamiento para el mismo período, caracterizada por tres factores principales: aumento proporcional de los restos de aves frente a otros recursos de mayor rédito calórico, formación de conjuntos con presencia casi exclusiva de restos de cormoranes en sitios con emplazamientos particulares y el incremento en la utilización de aves pelágicas (en particular Procellariiformes). En este trabajo se analiza si estas tendencias de cambio en la explotación de aves pueden o no entenderse como parte de una reorganización de la subsistencia más amplia, orientada hacia la intensificación en la captura de ciertos recursos.
La fauna de porte menor en sitios arqueológicos de la región pampeana, Argentina. Agente disturbador vs. recurso económico
Authors: Salemme Mónica , Escosteguy Paula , Frontini Romina
Published: April 2023

En este trabajo se discute la presencia de animales de porte mediano y pequeño, particularmente roedores, armadillos, aves y peces, en los conjuntos arqueofaunísticos de sitios ubicados en distintas áreas de la región pampeana (Argentina) y con cronologías que van desde el Holoceno temprano al Holoceno tardío. Se analiza su potencial como recurso económico explotado por los cazadores recolectores, así como su incidencia en los procesos de formación de sitios. El objetivo es plantear el rol de los taxa pequeños en el entorno ambiental y cultural, realizando un análisis comparativo a nivel espacial y temporal; asimismo, se analiza la acción antrópica sobre estos taxones y se generan interpretaciones sobre las estrategias económicas que involucraron su incorporación a la dieta y el aprovechamiento de otros subproductos. Los conjuntos estudiados provienen de la localidad arqueológica Cañada Honda y el sitio Río Luján (Noreste de la provincia de Buenos Aires); los sitios La Guillerma 1, La Guillerma 5 y San Ramón 7 (Depresión del Salado); Laguna Tres Reyes 1, Arroyo Seco 2 y El Guanaco (área Interserrana bonaerense) y Paso Mayor y Barrio Las Dunas (Sudoeste bonaerense).
Procesos de intensificación y aprovechamiento de médula y grasa ósea en el sur de Mendoza, Argentina
Authors: Otaola Clara
Published: April 2023

En este artículo se presenta la información sobre el aprovechamiento de médula y grasa ósea de dos sitios arqueológicos de la región cordillerana del sur mendocino. El objetivo de este análisis es indagar si se observan cambios sustanciales en el aprovechamiento de estos recursos en momentos en los que se ha planteado la existencia de un proceso de intensificación a nivel regional. En el marco de este contexto, buscamos indagar además, si la incorporación de la cerámica ha implicado también cambios en los modos de procesamiento de los nutrientes alojados en los elementos óseos. Los análisis comparativos entre conjuntos previos y posteriores a dicho proceso indican que, si bien se registran algunas modificaciones a favor de un aprovechamiento intensivo de la médula y grasa ósea, las variaciones en las variables analizadas no son tan contundentes como para defender un cambio de estrategia durante el Holoceno.
Ostras y vino en la ciudad hispanorromana de Baelo Claudia
Authors: Bernal-Casasola Darío , Cantillo Duarte Juan Jesús , Arévalo González Alicia , Muñoz Vicente Ángel
Published: April 2023

La presencia de restos de ostreidos en los contextos arqueológicos de época romana en los yacimientos del Círculo del Estrecho es una constante, desde inicios de la presencia romana hasta la Antigüedad Tardía. Incluso en Iulia Traducta (actual Algeciras), tenemos constancia de la existencia de viveros de ostricultura en pleno s. V d.C. La importancia de los restos malacológicos en el contexto de las actividades pesqueras y conserveras romanas es un elemento conocido en la ciudad de Baelo Claudia a través de diversas fuentes. En este trabajo presentamos los primeros datos de una actividad arqueológica realizada en el año 2009 en la muralla oriental de esta ciudad hispanorromana, en la cual se han exhumado diversas estructuras de época imperial. Entre ellas un contexto de abandono de mediados del s. I d.C. con múltiples ostras que denota la importancia del consumo de las mismas. Se presenta en esta comunicación la problemática del depósito, interpretado como desechos alimenticios de un convivium o banquete, así como una serie de inferencias históricas relacionadas con el procesado, consumo e importancia gastronómica de las ostras en esta importante ciudad romana del Estrecho de Gibraltar, centrada en la explotación de recursos marinos.
Interpretación tafonómica de la malacofauna marina en el yacimiento neolítico de la Caserna de Sant Pau del Camp (Barcelona)
Authors: Lloveras Lluís , Vicente Oriol , Molist Miquel , Nadal Jordi , Riera Santiago , Julià Ramon , Estrada Alícia
Published: April 2023

Los restos de conchas recuperados en el yacimiento neolítico de la Caserna de Sant Pau del Camp (Barcelona) se caracterizan por un gran número de elementos del género Glycymeris, muchos de ellos rodados por la actividad del mar. Por lo tanto, la mayor parte del registro arqueomalacológico no tiene un origen alimentario. La comparación con algunos análisis tafonómicos actualísticos podrían explicar este registro arqueomalacológico como resultado de elementos aportados por el mar. No obstante, los estudios geoarqueológicos demuestran que la línea de costa nunca llegó al yacimiento arqueológico, por lo que esta hipótesis debe ser invalidada. Por otra parte, hay una clara relación espacial entre las conchas y los enterramientos neolíticos.
Holocene coastal change and intertidal mollusc exploitation in the central mediterranean: variations in shell size and morphology at Grotta d’Oriente (Sicily)
Authors: Carlo Colonesse André , Lo Vetro Domenico , Martini Fabio
Published: April 2023

Grotta d’Oriente, en la isla de Favignana (NW Italia, Sicilia), presenta evidencias de la explotación humana de los recursos marinos en el periodo cronológico correspondiente al Holoceno antiguo (Mesolítico y transición Mesolítico-Neolítico). Este hecho, se corresponde con el registro de cambios importantes en la costa, ocurridos durante el aislamiento de Favignana de Sicilia. Los depósitos mesolíticos y meso-neolíticos contienen abundantes restos de moluscos intermareales, que ofrecen la oportunidad de explorar los posibles efectos de la explotación humana y de los cambios ambientales en los tamaños de los principales taxones recolectados (Patella caerulea/ulyssiponensis y Osilinus turbinatus).  Los resultados morfométricos revelan una disminución significativa en los tamaños de P. caerulea/ulyssiponensis entre la fase Mesolítica y Meso-neolítica, en relación con el momento de mayor explotación. Los datos de O. turbinatus, por el contrario, indican un cambio significativo en la forma que se refleja con conchas más altas y más bajas en el Mesolítico y Meso-Neolítico respectivamente. En el caso de P. caerulea/ulyssiponensis, las variaciones en las medidas parecen relacionadas sea con factores ambientales que con una posible intensificación de la recolección durante la fase Meso-neolítica, mientras que las variaciones en las conchas de O. turbinatus probablemente reflejan un cambio en la formación de la costa, que pasa de protegida a expuesta entre el Mesolítico y Meso-Neolítico respectivamente.
Comparison of foam models from regular and irregular arrays of Gibson-Ashby open-cells
Authors: Kornievsky A. S , Nasedkin A. V
Published: April 2023

The paper studies effective elastic properties of foam or cellular materials modeled by a set of Gibson-Ashby open cells with regular or irregular structures. Currently, there are many papers that present results of studying cellular materials using theoretical, numerical and experimental methods. However, these papers consider either regular lattices, or a single cell, or representative volume models based not on the Gibson-Ashby models. In this paper, in addition to the regular lattice, irregular structures were numerically studied. A mathematical formulation of the homogenization problem based on the energy equivalence of a foam-like material and on a homogeneous comparison medium is described. Formulations of six boundary value problems are presented. The solutions of these problems allow us to determine a complete set of effective stiffness modules for foams with different types of physical and geometric anisotropies. All stages of the numerical study were implemented in the ANSYS finite element package. Two algorithms for forming solid-state and finite-element models of irregular Gibson-Ashby lattices with small and large porosity are described in detail. As an example, numerical calculations are carried out for polycarbonate foams. The values of the effective elastic modules for regular and irregular lattices and for the Gibson-Ashby analytical model are compared. The results of numerical experiments showed that the Gibson-Ashby model describes the behavior of highly porous materials quite well (for porosity more than 75%), but this model gives a less satisfactory prediction in case of lower porosity. It is noted that for a large number of cells, regular and irregular lattices statistically give similar results for effective modules. However, for individual structures of irregular lattices, especially with strongly differing cells in individual directions, the effective moduli can have significantly different values, and the effective homogeneous medium can have pronounced anisotropic properties. These effects are due to geometric anisotropy and stress concentration in long connecting beams and at the joints of beams of various sizes in highly irregular Gibson-Ashby lattices. Examples of such lattices are given. We analyze the scatter of value for relative modules, which characterizes the anisotropy of such structures.
Frequency characteristics of built-in fiber-optic PEL-sensor to diagnose complex harmonic deformations within the polymer composite structure
Authors: Pan’kov A. A , Pisarev P. V
Published: April 2023

Fundamentals of operation of an optical fiber piezoelectroluminescent (PEL) sensor inside a polymer composite structure at its cyclic loading are considered. The optical fiber PEL-sensor is considered as part of the composite/sensor electromechanical system taking into account the presence of anisotropy, piezoactivity and Maxwell-Wagner relaxation of the electric fields of the sensor elements. The purpose of the optical fiber PEL-sensor is to diagnose the inhomogeneous complex volumetric deformed state of a long cylindrical area (a neighborhood along the built-in linear sensor) inside a cyclically loaded composite structure. A numerical model has been developed to solve the 3D related boundary value problem of electric elasticity for a representative fragment of the system composite/sensor in the ANSYS package. The numerical modeling of deformation and electric harmonic fields inside the representative fragment was carried out; in particular, distributions of amplitudes of these fields in elements of the structure of the optical fiber PEL sensor were found. The resonant modes are revealed, and the analysis is given of regularities of frequency dependences for the real and imaginary parts of controlling and informative transfer coefficients of the built-in fiber-optic PEL-sensor in the composite/sensor system. Additionally, graphs of frequency dependencies of tangents of mechanical loss angles for various cases of deformation of the composite/sensor system are given. Damping of the composite/sensor system is carried out as a result of the conversion of some part of the mechanical energy (transmitted from the composite to the sensor during their joint deformation) into Joule heat by the fiber-optic PEL sensor with a subsequent dispersion. The latter is caused by the direct piezoelectric effect and Maxwell-Wagner relaxation of electric fields in the sensor elements. The frequency range of deformation of the composite/sensor system is set, in which the passive vibration damping mode is most effectively implemented. It is numerically confirmed that for the extreme high-frequency case of deformation of the composite/sensor system, relaxation processes are not implemented and, as a result, solutions for the controlling and informative transfer coefficients of the PEL-sensor practically coincide with previously obtained numerical solutions that did not take into account the electrical conductivity of the sensor structure elements.
Crack growth in rotor P2M steel at elevated temperature
Authors: Shlyannikov V. N , Kosov D. A , Fedorenkov D. I , Zhang X. C , Tu S. T
Published: April 2023

The paper presents a comprehensive computational and experimental study of the crack growth rate during the creep-fatigue interaction in compact specimens of P2M steel at a temperature of 550 °C. The theoretical part of the study consisted in the formulation of the fracture resistance parameters through the classical and new constitutive equations of the cracked body state taking into account the accumulation of damage. Numerical calculations included the determination of the stress-strain state fields for the conditions of elasticity, plasticity, and creep, as well as the distributions of nonlinear stress intensity factors and the C*-integral along the crack length and along the crack front for each tested compact specimen. The interpretation of the experimental results for specimens of the same shape in plan but different thicknesses is given in terms of elastic and nonlinear stress intensity factors, taking into account the accumulation of creep damage. It was found that the crack growth rate under the fatigue and creep interaction increases monotonically as the crack size increases in comparison with harmonic fatigue by an order of magnitude or more on specimens of the same geometry. Taking into account the damage through the creep stress intensity factors causes differences in the cyclic fracture diagrams. The superposition of fatigue and creep contributions in terms of load holding time shows an order of magnitude increase in the total crack growth rate compared to the interpretation of the experimental data in terms of pure creep.
Crack root radius effect on stress fields under nonlinear
Authors: Boychenko N. V
Published: April 2023

The influence of crack root radius and plastic material properties on the crack tip fields was evaluated by strain gradient plasticity theory, and classical plasticity theory. A conventional mechanism-based strain gradient (CMSG) plasticity theory was used in the study. The stress fields in single edge tension specimen are investigated numerically for a wide range of the crack tip radius variations. Five values of the crack tip curvature radius ρ = 0 (mathematical notch); ρ = 25 nm, ρ = 30 nm, ρ = 60 nm and ρ = 100 nm were investigated. The strain hardening exponent varied from N = 0.075 to N = 0.4. A stress analysis by CMSG plasticity was performed for two values of the Taylor’s length parameter l = 1μm and l = 10μm. The boundaries of the local areas, where the influence of the crack tip radius is realized were determined for both HRR and CMSG plasticity. The sizes of the dominance area of the strain gradient plasticity were established and their approximation equations were presented. The influence of the plastic properties and the Taylor’s length scale parameter on the stress fields in the vicinity of rhe crack tip was estimated for the strain gradient plasticity.
Anti-icing indicator polymer coating with built-in fiber-optic PEL-sensor for indication, location and de-icing of aerodynamic surfaces
Authors: Pan’kov A. A , Pisarev P. V
Published: April 2023

A mathematical model was developed and a numerical modal analysis of the anti-icing mode of operation of the new indicator polymer coating with an integrated optical fiber piezoelectroluminescent (PEL) sensor for icing indication, location and self-cleaning from icing of aerodynamic surfaces was given. The fiber optic PEL-sensor is located in the plane of the coating. Receiver-analyzer of informative integral intensities of light signals is installed at output from optical fiber of sensor. Alternating voltage generator is connected to outputs of two control electrodes of sensor. The anti-icing function of the polymer coating is carried out automatically by thermo-mechanical actuation of the PEL-sensor on the appeared ice layer (on the ice crust of the coating) and only in those local areas of the coating where the thickness of the attached ice layer has reached a given critical value. Quality of cleaning from icing of surface of anti-icing coating is controlled by algorithms of digital processing of informative light signals at output from optical fiber of PEL-sensor. As a result, improved efficiency and control of de-icing on aerodynamic surfaces is achieved, especially for extended surfaces. The energy efficiency of the anti-icing polymer coating is increased due to the locality and self-control of the icing process. The modal analysis was carried out in an ANSYS finite element analysis package based on a numerical solution of the electrical-elasticity boundary value problem of stationary electromechanical oscillations of the representative cell of the anti-icing indicator polymer coating in the absence and presence of an ice layer of different thickness. Results of calculation of natural frequencies and forms of oscillations of representative cell of anti-icing coating, amplitude-frequency characteristics of mechanical stresses at coating/ice boundary for different values of thickness of attached ice layer for case of action of harmonic "force" in form of control electric voltage on electrodes of built-in PEL-sensor are presented.
Mathematical model of oxide film deformation on the surface of a metallic melt in an alternating magnetic field
Authors: Nikulin I. L , Demin V. A
Published: April 2023

We consider a thin oxide film on the surface of a molten metal during induction melting. The alternating electromagnetic field excites eddy currents in the metal volume, which heat it, and Lorentz force, which causes the forced convection of the melt, the heating and the flows in the metal are discussed briefly. The contribution to the mechanical stresses in the film that gives the alternating electromagnetic field, the thermal expansion of the film, and the melt motion are considered in detail. The equations system describing magnetic field diffusion, equations of motion and heat transfer in the melt are written in the axisymmetric formulation. The corresponding boundary conditions are described, the governing dimensionless criteria, which determine the structure and intensity of the melt flow, including those at the surface where the film is located, are given. The film elastic deformation equation is derived from Hooke's law and written in terms of displacement in dimensional and dimensionless forms. On the base of literature review, the values of physical characteristics of the film, which are not available for direct measurement, are proposed. The verification of the mathematical model is given. Possible flows in the melt are calculated, taking into account the action of dynamic and thermal action of the film on the surface. The unambiguous relation of the film stress state with these flows is shown. The influence of the magnetic field diffusion parameter and the Hartmann number, which determine, respectively, the structure and intensity of the forced flow, on the film deformations is demonstrated. The mode map of regimes is constructed that relates the integral deformation of the film to the parameters of the magnetic field and the initial size of the film. It is found that the situations are possible when the film in the stress-strain state does not change its total size and remains in stable equilibrium on the surface of the moving melt. Recommendations for the usage of the presented results are given.
About preliminary statistical processing of information on the study of fatigue strength of machine parts
Authors: Kulagin A. V , Russkih E. V
Published: April 2023

A generalized approach to statistical processing of the results is proposed fatigue parameters of static strength using methods of mathematical statistics and conventional statistics using the following probabilistic parameters: the mean square deviation, the initial moment, the central moment of dispersion and the coefficient of variation of the distribution series of physical and mechanical characteristics of the part material. Further, the analysis of fatigue strength research at the initial stage is carried out according to statistical information processing, graphical design of a number of stress distributions, statistical stress analysis, a graphical approach is applied in the form of a histogram of a number of distributions, a polygon of frequencies, a polygon of accumulated frequencies, the selection of theoretical stress distribution laws with their empirical confirmation is compared with a more rigorous assessment of the conformity of the distribution laws, which is performed using special consent criteria, for example, the Pearson criterion, a parallel verification of the correctness of the chosen approach using classical dependences of the resistance of materials is proposed. the total error is estimated in the form of a methodological error and a direct discrepancy between the theoretical and experimental values of stresses and temperatures of the physico-mechanical process according to experimental and theoretical normal and tangential stresses arising during the operation of the part as a result of the application of external force factors, a temperature-time superposition is used, in the form of a function of the predicted durability of the fluctuating kinetic theory of strength, in which the temperature, as a linear function, it can be replaced by any energy or force criterion, in particular: specific energy, relative deformation, normal or tangential stresses. The proposed approach requires substantial experimental study on a basic batch of the same type of samples and coordination according to schematized diagrams of the limiting amplitudes of Goodman, Sorensen - Kinasoshvili, Kogaev, subject to the conditions of safe operation of parts in the field of low-cycle fatigue. The proposed probabilistic model of statistical processing of fatigue strength can be recommended for solving applied problems of the theories of mechanics of materials, elasticity, plasticity and creep, resistance of materials, structural mechanics
Calculation of effective properties of geocomposites based on computed tomography images
Authors: Artamonova N. B , Sheshenin S. V , Orlov E. A , Bichen Zhou , Frolova J. V , Khamidullin I. R
Published: April 2023

Biot’s parameter is included in the formula for calculating effective stresses and should be taken into account when assessing the stress-strain state of a water-saturated rock mass. A method for calculating Biot’s tensor parameter based on asymptotic averaging of the equilibrium equation for a fluid-saturated porous medium is proposed. Calculations of elastic properties and Biot’s coefficient were carried out on various types of rocks - limestone, dolomite, hyaloclastite, basalt. The calculations were carried out using 3D models of geocomposites built from X-ray computed tomography images. The results of 3D calculations of Young's modulus and Biot’s coefficient coincided with the results of experimental determinations of these properties by the ultrasonic method. This fact shows the expediency of using a computational approach that implements asymptotic averaging to estimate the effective properties using 3D models of the real rock structure. The results of 3D and 2D simulation of effective properties of geocomposites are compared. 2D models were built using photographs of rock sections. It was found that the values of Young's modulus and Biot’s parameter for 2D models differ from the corresponding experimental and 3D calculation results by 20-30 %. Therefore, 2D modeling is not suitable for evaluating the effective properties of porous geomaterials. Based on the results of calculations and experiments, the dependences of Young's modulus and Biot’s coefficient on porosity were obtained and studied. These dependencies are used in non-linear numerical simulation of the consolidation of water-saturated soils. The results of the study showed that Biot’s coefficient does not depend on Young's modulus of the rock skeleton material. The influence of the pore shape on Young's modulus and Biot’s coefficient was studied using 2D calculations. A method for predicting the shape of pores from the values of porosity and Young's modulus using neural networks is proposed. Using this method, a specific algorithm for predicting the shape of pores in hyaloclastites has been implemented and studied.
Development of the digital image correlation (DIC) method for mechanical testing at elevated temperatures
Authors: Strungar E. M , Lobanov D. S
Published: April 2023

The results of experimental studies on the evaluation of the performance of the non-contact optical video system Vic-3D and the digital image correlation method during tensile tests of composites under normal and elevated temperatures are presented. The dependences of the recorded strain values are analyzed by two independent measurement methods: the digital image correlation method (DIC) and a mounted extensometer. The tests were carried out at the Center of Experimental Mechanics of the Perm National Research Polytechnic University using the Instron 5882 universal electromechanical testing system, which includes a thermal chamber with an operating temperature range of -100° to +350 °С. Samples of a composite material made of STEF fiberglass and carbon fiber were studied. Tensile tests were carried out at temperatures of 2°2, 100°, 120°, 200°, and 300°C. Recommendations for conducting temperature tests using the DIC method are proposed. Based on the test results, deformation diagrams were constructed. Fields and diagrams of longitudinal deformations are obtained at different temperature levels. A detailed evaluation of the finely dispersed coating required for the implementation of the DIC method in temperature tests has been carried out.
Prise en charge des tumeurs germinales du testicule de stade I
Authors: LE MOULEC S. , BAUDUCEAU O.
Published: April 2023

Les tumeurs germinales du testicule sont les tumeurs malignes les plus fréquentes de l’homme jeune. Actuellement,
aucune métastase n’est décelable au diagnostic chez 80 % des patients. Le traitement débute toujours par l’orchidectomie.
En cas de séminome pur, trois options doivent être discutés : radiothérapie prophylactique à dose et volume réduits,
surveillance armée ou chimiothérapie par carboplatine. En cas de tumeur germinale non séminomateuse, trois options
doivent être également envisagés : surveillance, chimiothérapie par deux cycles du protocole BEP ou curage
ganglionnaire rétropéritonéal. La stratégie utilisée doit prendre en compte les facteurs de risque de récidive et les souhaits
du patient. Quelle que soit l’option retenue, le taux de guérison dépasse 99 %.
А locally adaptive wavelet filtering algorithm for images
Authors:   Novosibirsk State University of Architecture and Civil Engineering (Sibstrin), Russian Federation, Voskoboinikov Yuri E. ,   Novosibirsk State Technical University, Russian Federation,   Melentiev Energy Systems Institute of Siberian Branch of the Russian Academy of Sciences, Irkutsk
Published: April 2023

The algorithms based on the decomposition of a noisy image in an orthogonal basis of wavelet functions have been widely used to filter images (especially contrasting ones) over the past four decades. In this case, most wavelet filtering algorithms are of a threshold nature, namely: the decomposition coefficient smaller in an absolute value of a certain threshold value is reset to zero; otherwise the coefficient undergoes some (most often nonlinear) transformation. A certain (and very significant) drawback of threshold algorithms is that all coefficients of a certain decomposition level are processed with one identical threshold value (i.e., a constant value for all de-composition coefficients). This does not allow taking into account the “individual energy” of each decomposition coefficient for its more optimal processing. Therefore, we propose its own filtering factor for each coefficient, built on the basis of the optimal Wiener filtering and where a filtering parameter is introduced to compensate for incomplete a priori information on the value of the processed decomposition coefficients. In order to select a filtering parameter, a statistical approach has been proposed that makes it possible to estimate the optimal value of this parameter with acceptable accuracy. The performed computational experiment has shown the developed algorithm effectiveness for wavelet filtering of images.
Analysis of information security standards
Authors:   St. Petersburg National Research University of Information Technologies, Mechanics and Optics, Russian Federation, Klishin Danil V. , Chechulin Andrey A. ,   St. Petersburg Federal Research Center of the Russian Academy of Sciences
Published: April 2023

The purpose of the work is to systematize the available knowledge about information security models presented in standards and scientific research to solve the problem of labor intensity: analysis and selection of an information security model relevant to the information infrastructure of the enterprise; and assessment of the current level of information security of the enterprise. When in identifying and analyzing the information security models used, standards, regulatory legal acts and scientific research in the field of information security are considered within the framework of this work. The systematization of knowledge about information security models was carried out with the help of analysis of standards, scientific research, normative legal acts on information security; identifying common properties of information security models; grouping criteria and evidence confirming the implementation of information security measures by common signs; identifying ways to automate the assessment of the current level of information security. In the course of the work: the main criteria of the information security model were identified; a list of certificates was formed that allow monitoring the implementation of information security measures; common features of criteria, certificates sufficient for grouping were revealed; types of certificates were identified; an algorithm for assessing the current level of information security of an enterprise was formed; methods of automatization of collecting information about models of information security used by an enterprise and evidence of the implementation of information security measures were identified . This work systematizes knowledge about the existing models and allows analyzing the criteria of information security without a need to study all the standards and scientific papers considered in this work, which reduces the labor intensity of the analysis and selection of an information security model relevant to the information infrastructure of an enterprise. The results of this work will be applied to identify the possibility of automating the assessment of the current level of information security of an enterprise.
Termal analiz ve iyileştirilmiş tutucu tasarımı ile 1.5 W Lazer Diyot çift-uç pompalı levha geometrisine sahip Cr:Nd:GSGG lazer sistemi
Authors: ÖZTÜRK Yusuf , KILINÇ Muharrem , BUZCU Halime Nur , ERTÜRK Zekican
Published: April 2023

Bu çalışmada katı-hal lazerlerde önlenemeyen sıcaklık etkileri karakteristiğinin kapsamlı analizini ve kazanç ortamında üretilen ısı için uçtan uca çözüm sunulmaktadır. Isı etkilerinin azaltılarak lazerin verimliliğini artırmak amacıyla temel fiziksel mekanizmalar (Quantum Kusuru, Yukarı Dönüştürme ve Floresans Yaşam Süresinin Termal Sönümlenmesi) açıklanarak kavitenin pratik çalışma koşullarında kullanılabilecek uygun bir tutucu tasarımı için Toplam Isı Üretim Katsayısı hesaplanmıştır. Özellikle çeşitli pompalama senaryolarıyla kullanılan Cr:Nd:GSGG kristallerindeki termal lens etkisinin teorik hesaplamalarında sonlu-elemanlar yöntemiyle benzetimler gerçekleştirilmiştir. Öngörülen termal uyarımlı gerilimler daha önce deneysel olarak gözlemlenen değer ile karşılaştırılmıştır. Son aşamada, 1.5W Gaussian (TEM00) çift uç pompalı levha geometrili Cr:Nd:GSGG kristalinin benzetimi yordamıyla yeni tip kristal tutucu tasarımı için gerekli hesaplama yapılmıştır. Sonuçlar derinlemesine tartışılarak bu kazanç ortamı için yeni tutucu tasarımının uygun olduğu gösterilmiştir
Spektrum paylaşım modelinde ikincil kullanıcıların Nakagami-m ve Log-normal sönümlemeli kanallar üzerindeki kapasite analizi
Authors: BAŞGÜMÜŞ Arif , ARDIÇ Maide Sultan , NAMDAR Mustafa
Published: April 2023

Bu çalışmada, bilişsel radyo ağı için spektrum paylaşım modelinde birincil kullanıcıdan gelen girişimin etkisi dikkate alınarak, ortalama alınan güç kısıtlaması altında ikincil kullanıcı için ergodik kapasite performansı analiz edilmektedir. Kapasiteyi maksimuma çıkaran su doldurma çözümü ve güç tahsisi yaklaşımı ile Nakagami-m ve log-normal dağılımlı sönümlemeli kanallar üzerinde ergodik kapasiteye ilişkin teorik çıkarımlar türetilmektedir. Nümerik sonuçlar, birincil ağ kaynaklı girişim kanallarının, ikincil kullanıcının kapasitesi üzerinde önemli ölçüde etki oluşturduğunu göstermektedir. İkincil kullanıcı için ergodik kapasite performansı; Nakagami dağılımın sönümleme parametresi, log-normal dağılımın standart sapması ve ikincil kullanıcın optimum gücünü belirleyen Lagrange çarpanı parametreleri dikkate alınarak, Monte Carlo benzetimleriyle doğrulanmaktadır.
Eklemeli imalat yöntemlerinde vakum infüzyon yolu ile üretim optimizasyonu
Authors: KARAKUŞ Raşit , TANIK Çağıl Merve
Published: April 2023

Üç boyutlu yazıcılar yeni bir üretim metodu olarak endüstride birçok alanda kullanılmaktadır. Esnek mekanizma üretiminde de bu yöntemin kullanımı gün geçtikçe yaygınlaşmaktadır. Bu çalışmada üç boyutlu yazıcıların üretim etkinliğinin arttırılması ve bu yöntemin ileriki çalışmalarda esnek mekanizmalara da uygulanabilmesi amaçlanmıştır. Üretim hızının arttırılarak daha yüksek mukavemetlerde numunelerin elde edilmesi amacıyla testler düzenlenmiştir. Bu amaçla farklı doluluk oranlarında, gyroid geometri kullanılarak test numuneleri hazırlanmıştır. %10, %20, %40 ve %60 doluluk oranlarındaki numunelerin üretim hızları kaydedilmiştir. Her numuneden, beşer adet reçine emdirilmiş ve emdirilmemiş test numuneleri hazırlanmıştır; çekme ve eğilme testleri bu numuneler kullanılarak gerçekleştirilmiştir. Elde edilen sonuçlar düzenlenerek dayanım, üretim süresi ve üretim maliyeti açısından karşılaştırılmıştır.