Direct Proportion Research Articles

Газоприводная скважинная насосная установка для добычи нефти из наклонных и горизонтальных скважин

The design of a gas-driven downhole pumping unit for oil production from directional and horizontal wells has been developed. The unit has no rod string, the slide and pneumatic jack are located in the tubing string. Using these units with a compressed associated gas as a working fluid will allow, unlike the hydraulic pumps, avoiding complex surface equipment for preparing the working fluid, maintenance of which is rather labour-consuming, and increasing the reliable operation of slides and downhole pumping units as a whole. In the course of experimental study of the parameters of the proposed installation it was shown on a laboratory bench showed that the fluid feed increases in direct proportion to the rate from 0.6 to 3.6 m/min. There has been obtained an empirical dependence to determine the flow of a borehole pump depending on its geometric parameters, plunger stroke length, stroke speed and gas content in the produced oil. According to the estimated parameters of the developed gas-driven unit, the supply can reach 386 m3/day, which is comparable to the supply of hydraulic units in use.

Study on the Occurrence Difference of Functional Groups in Coals with Different Metamorphic Degrees.

In order to quantitatively study the difference in occurrence content of functional groups in coals with different metamorphic degrees, the samples of long flame coal, coking coal, and anthracite of three different coal ranks were characterized by FTIR and the relative content of various functional groups in different coal ranks was obtained. The semi-quantitative structural parameters were calculated, and the evolution law of the chemical structure of the coal body was given. The results show that with the increase in the metamorphic degree, the substitution degree of hydrogen atoms on the benzene ring in the aromatic group increases with the increase in the vitrinite reflectance. With the increase in coal rank, the content of phenolic hydroxyl, carboxyl, carbonyl, and other active oxygen-containing groups gradually decreased, and the content of ether bonds gradually increased. Methyl content increased rapidly first and then increased slowly, methylene content increased slowly first and then decreased rapidly, and methylene content decreased first and then increased. With the increase in vitrinite reflectance, the OH-π hydrogen bond gradually increases, the content of hydroxyl self-association hydrogen bond first increases and then decreases, the oxygen-hydrogen bond of hydroxyl ether gradually increases, and the ring hydrogen bond first significantly decreases and then slowly increases. The content of the OH-N hydrogen bond is in direct proportion to the content of nitrogen in coal molecules. It can be seen from the semi-quantitative structural parameters that with the increase in coal rank, the aromatic carbon ratio fa, aromatic degree AR and condensation degree DOC increase gradually. With the increase in coal rank, A(CH2)/A(CH3) first decreases and then increases, hydrocarbon generation potential 'A' first increases and then decreases, maturity 'C' first decreases rapidly and then decreases slowly, and factor D gradually decreases. This paper is valuable for analyzing the occurrence form of functional groups in different coal ranks and clarifying the evolution process of structure in China.

Spectrophotometric and Smartphone-based Dual Monitoring Method for the Determination of Al(III) Ions Using Fermented Black Carrot Juice (Şalgam/Shalgam) as a Green Chromogenic Agent

In this study, anthocyanin-rich fermented black carrot juice (şalgam/shalgam) was used as a chromogenic agent in order to develop eco-friendly, low-cost, simple, fast, and practical both visible spectrophotometric and smartphone-based methods for the determination of Al(III) ions in water samples. Formation of Al(III)-anthocyanin complex results in a color change from red to purple in direct proportion to the increasing Al(III) concentration. For the spectrophotometric analysis, the analytical response of the developed method between absorbance and logarithm of Al(III) concentration exhibits a satisfying wide linear concentration range from 37.0 to 1850.0 µM. The LOD and LOQ values are 6.67 µM and 22.0 µM, respectively. For smartphone-based analysis, the analytical response of the developed method between B values and Al(III) concentration obtained a linear concentration range from 18.5 to 111.0 µM. The LOD and LOQ values are 4.40 µM and 14.5 µM, respectively. LOD values are below the acceptable limit of Al(III) in water according to WHO (7.41 µM) for both methods. The interfering effect of common water ions was investigated, and the observed interferences from Sn2+, Fe2+, and Fe3+ were easily eliminated using enough concentration of Na2EDTA without affecting the blank absorbance/B value of the Al(III)−anthocyanin complex for two monitoring methods. The selectivity of the developed method was investigated in the presence of possible species such as benzoic acid, lactic acid, amino acids, and salt. Developed spectrophotometric and smartphone-based methods applied to real water samples and validated against the reference ICP-OES method at 95% confidence level using Student’s t- and F-tests.

ФОРМУВАННЯ ПРОДУКТИВНОСТІ КВАСОЛІ ЗВИЧАЙНОЇ ЗАЛЕЖНО ВІД СОРТІВ, ІНОКУЛЯЦІЇ ТА УДОБРЕННЯ

Ріст і розвиток рослин квасолі прямо залежить від умов навколишнього середовища, основними складниками якого є температура повітря та ґрунту, освітленість, вологість, мінеральне живлення. Продуктивність рослин зумовлюється наявністю цих факторів, і чим більше вони відповідають біологічним особливостям культури, тим повніше реалізуються потенційні можливості сортів квасолі. Під час дослідження насіння квасолі звичайної перед сівбою обробляли різними штамами мікроорганізмів. Залежно від цього дещо змінювалися міжфазні періоди росту й розвитку рослин. Тривалість періоду «сівба – повна стиглість» у рослин квасолі сорту Ластівка, інокульованих різними штамами Rhizobium phaseoli, у середньому за період дослідження 2020–2022 рр. відрізнялася на 1–3 доби.

The Relationship between Mental Health and Sleeping Quality in COVID-19: The Moderating Effect of the Attachment Style

During the epidemic, the mental health and sleeping quality of college students were affected to varying degrees, which may influence the quality of life and well-being. This cross-sectional aimed to determine the frequency of psychologically negative states and poor sleeping quality among undergraduate students during the Covid-19 pandemic and explore the correlation between mental health and sleeping quality and the moderating effect of the attachment style. Relevant information was collected with an online questionnaire, which was distributed among 72 undergraduate students at prestigious universities in Shanghai and Nanjing. The mental health status of the subjects was assessed using the Depression, Anxiety, and Stress Scale - 21 (DASS-21), the sleep quality of the students using the Pittsburgh Sleep Quality Index (PSQI) questionnaire and the attachment style using the Experiences in Close Relationships Inventory (ECR). The study revealed that 70% of the subjects were suffering stress of different levels, two-thirds of them were undergoing varying degrees of depression, and nearly 85% were bearing anxiety after the outbreak of COVID-19. The prevalence of poor sleeping quality among college students was 36.2%. The study concluded that stress, anxiety and depression index were all in direct proportion to the level of sleeping problems. The attachment style may play a more or less role in moderating the direct proportion. The findings could help choose appropriate interventions to try to solve the mental and sleep problems for people with different attachment styles.

Colonization of Artificial Substrates by Invertebrate Macrofauna in a River Ecosystem-Implications for Forensic Entomology.

Forensic entomology includes the analysis of organisms colonizing various parts of the body in order to determine the circumstances of an incident, mainly the time, place, and cause of death. The presence of insects and other arthropods on carcasses can be a source of knowledge for the judicial system. However, this type of research (on submerged bodies) is less published. The aim of our study was to analyse the qualitative and quantitative structure of macroinvertebrates colonizing potential evidence in an upland river. The experimental research involved an eight-week exposure to articles of clothing made of different materials: natural materials (bottom sediments with plants from a river), synthetic (socks), and cotton (t-shirts). Control samples of water after 2, 4, 6, and 8 weeks were taken from experiment locations in the River Bystrzyca with a tube apparatus and hand net. The results indicated that the abundance of organisms on a given substrate depended on the period of development of invertebrate macrofauna and the time of exposure of the substrates. The abundance of aquatic macrofauna on the exposed items increased in direct proportion to the duration of the experiment, which may indicate the adaptability of these organisms to new habitat conditions. Among the taxonomic groups used in forensic entomology, Diptera, Coleoptera, and Odonata were the most abundant. The remaining taxa (including Heteroptera), though not widely used in judicial proceedings, can also provide valuable information about the circumstances of an incident.

Sizing up spotted lanternfly nymphs for instar determination and growth allometry.

A major ongoing research effort seeks to understand the behavior, ecology and control of the spotted lanternfly (SLF) (Lycorma delicatula), a highly invasive pest in the U.S. and South Korea. These insects undergo four nymphal stages (instars) before reaching adulthood, and appear to shift host plant preferences, feeding, dispersal and survival patterns, anti-predator behaviors, and response to traps and chemical controls with each stage. However, categorizing SLF life stage is challenging for the first three instars, which have the same coloration and shape. Here we present a dataset of body mass and length for SLF nymphs throughout two growing seasons and compare our results with previously-published ranges of instar body lengths. An analysis using two clustering methods revealed that 1st-3rd instar body mass and length fell into distinct clusters consistently between years, supporting using these metrics to stage nymphs during a single growing season. The length ranges for 2nd-4th instars agreed between years in our study, but differed from those reported by earlier studies for diverse locations, indicating that it is important to obtain these metrics relevant to a study's region for most accurate staging. We also used these data to explore the scaling of SLF instar bodies during growth. SLF nymph body mass scaled with body length varied between isometry (constant shape) and growing somewhat faster than predicted by isometry in the two years studied. Using previously published data, we also found that SLF nymph adhesive footpad area varies in direct proportion to weight, suggesting that footpad adhesion is independent of nymphal stage, while their tarsal claws display positive allometry and hence disproportionately increasing grasp (mechanical adhesion). By contrast, mouthpart dimensions are weakly correlated with body length, consistent with predictions that these features should reflect preferred host plant characteristics rather than body size. We recommend future studies use the body mass vs length growth curve as a fitness benchmark to study how SLF instar development depends on factors such as hatch date, host plant, temperature, and geographic location, to further understanding of life history patterns that help prevent further spread of this invasive insect.

Short-term effects of solar storms in phytoplankton photosynthesis

The potential short-term influence of a solar radiation storm on microalgal photosynthesis is investigated. We focus on muons from the secondary cosmic rays at sea level, given their high penetrating power. According to NOAA’s classification of solar radiation storms, two kinds of solar storms are considered: moderate/strong and extreme. An exponential decay of muon fluxes down the water column and a direct proportionality between their penetrating power and energy are assumed. This allows obtaining a function of ionizing radiation to be embedded in a physical-mathematical model for photosynthesis previously modified by some of us to include particulate ionizing radiation. It is shown that moderate/strong solar radiation storms can cause a short-term depletion of photosynthesis of up to 61%, while this figure scales to 75% for extreme storms.

Experimental investigation on high-temperature tensile behavior of cold metal transfer pulse multi-control welding of Inconel 617 alloy

To improve the efficiency of the advanced steam power plants, both the pressure and temperature of the steam are increased. The Inconel 617 alloys are a candidate material for these applications. The microstructural features and tensile characteristics of welded joints made using the cold metal transfer (CMT) plus pulse multi-control (PMC) by varying the wire feed speed (8.9, 9.4, and 9.9 m/min) at room and high temperatures (650 °C, 700 °C, and 750 °C) are examined. An optical microscope (OM) and Field emission scanning electron microscope (FESEM) were used to examine the microstructure and fracture surfaces of the alloy. The mechanism of strengthening and the effects of precipitates on tensile strength and % elongation in both Base metal (BM) and weld bead are discussed in detail. The mechanical behavior was analyzed in terms of impact strength and bending strength in detail by varying the wire feed speed (WFS). Indications for porosity and cracks were not reported in the X-ray radiography test. The macrographs revealed that bead width, penetration depth, the metal deposited on the weld, and HAZ are in direct proportion with wire feed speed. Bend test results showed that the weld joints exhibit good ductility without cracks.

Influences of the number of non-consecutive joints on the dynamic mechanical properties and failure characteristics of a rock-like material

The dynamic mechanical properties and failure characteristics of jointed rocks are the focus of research in rock engineering. In this study, cement mortar specimens with 0–4 parallel non-consecutive joints were prepared. The split Hopkinson pressure bar (SHPB) was used for dynamic impact testing of prepared specimens. Nuclear magnetic resonance (NMR) was used to detect the pore structure deterioration of the specimens after impact. Finally, the failure characteristics of the specimens were studied by extracting the surface cracks of the specimens. The results show that the number of non-consecutive joints have a significant effect on the dynamic mechanical properties of cement mortar specimens. The increased number of joints will change the stress–strain curve from a single-peak shape to a multi-peak shape and enhance the ductility. The dynamic peak strengths and the proportion of dissipated energy of the specimens decrease with the increase of number of joints, but the magnitude of change decreases gradually. NMR analysis reveals the pore structure alterations of the specimens. After being impacted, the internal pores of the specimens increase significantly, especially the macro-pores and micro-pores. Some micro-pores become meso-pores and macro-pores, and some pores are connected. These changes of microscopic pore structure lead to macroscopic failure of specimens. A quantitative analysis of the porosity of the specimens shows that the rate of change in porosity is in direct proportion to the number of joints, which means that the greater the number of joints, the larger the damage degree of the specimens. The failure characteristics of the specimens indicate that tensile stress mainly dominates the fracture behavior of the specimens, while shear stress has limited damage to the specimens. After the tensile wing cracks start from both tips of the joint, they extend along the rock bridge to the adjacent joint or the end of the specimen. After the wing cracks coalesce, they form a rectangular failure zone. In addition, axial tensile cracks will start near the middle of the first joint and the middle of the last joint, extending to the top and bottom of the specimen, respectively. Slight shear cracks only develop at the joint ends.

Physical, mechanical, viscoelastic, and morphological properties of poly(lactic acid)/ethylene‐co‐vinyl acetate blend reinforced with silicon carbide nanoparticles

AbstractPhase morphology, mechanical properties, melting and crystallinity, as well as the dynamic viscoelastic properties of poly(lactic acid) (PLA)/ethylene‐co‐vinyl acetate (EVA) (80/20) blend containing 0–3 wt% nano‐silicon carbide (SiC) were studied. Morphological observations revealed the localization of nano‐SiC particles around the EVA droplets with the consequence of a fall in the size of EVA dispersed phase in the nanocomposites compared with the unfilled blends. The mechanical characterization results showed a gradual increase in the elastic moduli and yield stress with increasing nano‐SiC content in the nanocomposites, while the strain at break and Izod impact strength were steadily decreased. The nano‐SiC particles served as nucleating agents for crystallization of the PLA matrix from the molten state. The crystallinity of the PLA matrix in the nanocomposites was slightly reduced compared with that of the unfilled blend. The dynamic mechanical thermal analysis results showed a gradual increase in the glass transition temperature of PLA matrix together with a steady decline of damping capability as the nano‐SiC content in the nanocomposite was increased. The dynamic rheological data demonstrated enhanced complex viscosities and storage moduli of the nanocomposites in a direct proportion to the nanofiller loading, specially at the low‐frequency region. The changes occurred in the various properties of the fabricated nanocomposites were interpreted in terms of alteration in the phase morphology and the physical interactions of the nano‐SiC particles with the blend's components.

Muon and electron (g-2) anomalies with non-holomorphic interactions in MSSM

The recent Fermilab muon g-2 result and the same for electron due to fine-structure constant measurement through {}^{133}textrm{Cs} matter-wave interferometry are probed in relation to MSSM with non-holomorphic (NH) trilinear soft SUSY breaking terms, referred to as NHSSM. Supersymmetric contributions to charged lepton (g-2)_l can be enhanced via the new trilinear terms involving a wrong Higgs coupling with left and right-handed scalars. Bino-slepton loop is used to enhance the SUSY contribution to g-2 where wino mass stays at 1.5 TeV and the left and right slepton mass parameters for the first two generations are considered to be the same. Unlike many MSSM-based analyses completed before, the model does not require a light electroweakino, or light sleptons, or unequal left and right slepton masses, or a very large higgsino mass parameter. In absence of popular UV complete models, we treat the NH terms at par with MSSM soft terms, in a model independent framework of Minimal Effective Supersymmetry. The first part of the analysis involves the study of (g-2)_mu constraint along with the limits from Higgs mass, B-physics, collider data, direct detection of dark matter (DM), while focusing on a higgsino DM which is underabundant in nature. We then impose the constraint from electron g-2 where a large Yukawa threshold correction (an outcome of NHSSM) and opposite signs of trilinear NH coefficients associated with mu and e fields are used to satisfy the dual limits of Delta {a_mu } and Delta {a_e} (where the latter comes with negative sign). Varying Yukawa threshold corrections further provide the necessary flavor-dependent enhancement of Delta {a_e}/m_e^2 compared to that of Delta {a_mu }/m_mu ^2. A larger Yukawa threshold correction through A^prime _e for y_e also takes away the direct proportionality of a_e with respect to tan beta . With a finite intercept, a_e becomes only an increasing function of tan beta . We identified the available parameter space in the two cases while also satisfying the ATLAS data from slepton pair production searches in the plane of slepton mass parameter and the mass of the lightest neutralino.

Size-Dependent Oscillation in Optical Spectra from Fly Ash Cenospheres: Particle Sizing Using Darkfield Hyperspectral Interferometry

Abstract Fly ash by-products are emerging biocompatible fillers for a number of construction materials. The value of fly ash as a filler is higher if the content of hollow cenospheres is increased. Here we describe a new method for detection and sizing of fly ash spheres based on darkfield microscopy with hyperspectral image capture to perform white light interferometry. Our method is cost-effective and can provide rapid means for evaluating cenosphere content during the enrichment process. We show that fly ash cenospheres produce a strong oscillation over wavelength in optical recordings. The phenomenon is easiest to observe using microscope imaging techniques that preserve both spatial and spectral information. Frequency is observed to increase in direct proportion to the sphere diameter. The oscillation appears in light recorded from any focal plane on the sphere which indicates that the entire sphere is involved in sustaining the signal, making the detection of cenospheres of different size and displacement within a recording volume productive. There is no oscillation from nonspherical particles of fly ash or other material, so this detection method is highly selective for the cenospheres.

Supplementation of Polymeric Reservoirs with Redox-Responsive Metallic Nanoparticles as a New Concept for the Smart Delivery of Insulin in Diabetes.

Type 1 diabetes is caused by the inability of the pancreatic beta cells to produce sufficient amounts of insulin, an anabolic hormone promoting the absorption of the blood glucose by various cells in the body, primarily hepatocytes and skeletal muscle cells. This form of impaired metabolism has been traditionally treated with subcutaneous insulin injections. However, because one such method of administration does not directly correspond to the glucose concentrations in the blood and may fail to reduce hyperglycemia or cause hypoglycemia, the delivery of insulin in a glucose-dependent manner has been researched intensely in the present and past. This study tested the novel idea that the supplementation of polymeric reservoirs containing insulin with metallic nanoparticle precursors responsive to the redox effect of glucose could be used to create triggers for the release of insulin in direct response to the concentration of glucose in the tissue. For that purpose, manganese oxide nanoparticles were dispersed inside a poly(ε-caprolactone) matrix loaded with an insulin proxy and the resulting composite was exposed to different concentrations of glucose. The release of the insulin proxy occurred in direct proportion to the concentration of glucose in the medium. Mechanistically, as per the central hypothesis of the study, glucose reduced the manganese cations contained within the metal oxide phase, forming finer and more dissipative zero-valent metallic nanoparticles, thus disrupting the polymeric network, opening up pores in the matrix and facilitating the release of the captured drug. The choice of manganese for this study over other metals was justified by its use as a supplement for protection against diabetes. Numerical analysis of the release mechanism revealed an increasingly nonlinear and anomalous release accompanied by a higher diffusion rate at the expense of chain rigidity as the glucose concentration increased. Future studies should focus on rendering the glucose-controlled release (i) feasible within the physiological pH range and (ii) sensitive to physiologically relevant glucose concentrations. These technical improvements of the fundamental new concept proven here may bring it closer to a real-life application for the mitigation of symptoms of hyperglycemia in patients with diabetes.

The Deficits of Students' Orientation in Solving Proportion Problems, as Revealed through Task Modifications.

Using the Activity Theory of education (Galperin, 1992; Talyzina, 2018), this article examines the students' actions that constitute the early stages of forming the concept of ratios. The psychological analysis of mastery of this concept shows that it essentially depends on understanding the coordination of the changes of two independent values (area, velocity, density, etc.). The present research considers differences in students' operations with numbers on various tasks, based on their comprehension of ratio relations (direct and inverse proportions); these differences are revealed through posing certain modified tasks, but may stay unnoticed in regular tasks. The goal of the study was to identify the criteria for adequate assessment of the sustainability of the students' orientation in modified tasks. A test of 15 tasks was designed based on Galperin's classification of task variations: domain specific, logical, and psychological. The formulation of the tasks disguised the operations needed to achieve the right answer, and sometimes even prompted the wrong solution. There were 12 tasks on direct proportions - four sample and eight modified; and three inverse proportion tasks: one sample and two modified. One hundred sixty (160) students (5-6th grade, 11-13 years old) took the test in writing. The comparison of students' performance on the sample and modified tasks showed significant differences. Modifications impaired the students' performance on both types of proportion problems (direct and inverse). Logical and psychological modifications had the most impact on the quality of the students' orientation and thus proved to be most indicative in terms of students' orientation quality assessment. The data suggest the following: 1) that the concepts of proportionality which the students acquired from a regular school curriculum lack "generalization," and 2) that students' ability to apply the ratio concept is very sensitive to the way the word problem is presented. These findings are essential for evaluating students' multiplicative thinking: their actual level of comprehension cannot be revealed through their performance on regular tasks.

An index to prevent major limb amputations in diabetic foot.

Objective. Besides the early detection and treatment of diabetic foot ulcers, being aware of the risk factors for major amputation plays a crucial role in preventing the major lower limb amputations. Major lower limb amputations are not just mentally and physically hard for patients, but also have an effect on patient's survival and are a financial burden on both patients and healthcare systems. Subjects and Methods. We defined 37 potential risk factors for major amputation and these risk factors were investigated among 507 patients who had ulcers in their feet and were seen by the diabetic foot ulcer council at Ege University Faculty of Medicine. In our study, 106 (20.9%) patients ended up undergoing major lower limb amputation. Results. The univariate analysis showed that 24 defined risk factors were statistically significant. In the multivariate analysis using the Cox regression model, 6 risk factors remained statistically significant. Multivariate-adjusted hazard ratios were 4.172 for hyperlipidemia, 3.747 for albumin <3.365 g/dL, 3.368 for C-reactive protein (CRP) >2.185 mg/L, 2.067 for presence of gangrenous Wagner stage, 1.931 for smoking tobacco >30 pack/year, and 1.790 for hematocrit (HCT) <31.5%. Most patients with major amputation presented with a neuroischemic foot (58%). Gender and age were not found to be risk factors for major amputation. Having less than 7% of hemoglobin A1c (HbA1c) levels had a direct proportion with major amputation numbers. The mortality rates in one year, two and three years after the major amputation operations were 24.6%, 30%, and 35.9%, respectively. Conclusion. Being familiar with these risk factors for major amputation is crucial for multi-disciplinary teams to take good care of patients with diabetic foot ulcers and to lower the need for major amputations.

Heat Transfer Analysis of Generalized Nanofluid with MHD and Ramped Wall Temperature Using Caputo–Fabrizio Derivative Approach

The aim of the present work is to apply the fractional derivative to the heat transformation of a nanofluid along with ramped wall temperature. The flow is analyzed under the effect of magnetohydrodynamic together with heat transfer. A nanofluid under the application of fractional‐order differential equations by Caputo–Fabrizio derivatives with respect to time has the ability to explain the behavior of nanofluid under the influence of memory concept. For the same purpose, Caputo–Fabrizio time‐fractional derivative is applied to investigate the behavior of nanoparticles on the thermal conductivity of a fluid. Appropriate nondimensional variables are engaged in the equation which governs the problem and guides us to obtain the exact solutions for the fields of velocity and temperature. These obtained solutions for the nondimensional set of governing equations are found by extracting them from the governing equations by applying Laplace transform techniques along with Caputo–Fabrizio time‐fractional derivative. The influence of the fractional variable on the velocity, temperature, and Nusselt number is graphically exposed and discussed. The velocity for the state of wall temperature as ramped falls down with the enlarging values of the fractional parameter. Variation in Nusselt number is shown in the tabular form. Solutions are visualized graphically to make an analysis of how the variation is taking place in the physical behavior of the nanofluid flow with respect to the change in distinct physical parameters. The obtained results here will have useful industrial and engineering implementations. It is found that fluid velocity in the flow direction decreases with the increase in the magnetic parameter. The relationship of fractional parameter with the velocity and temperature of the nanofluid is found as direct proportional for a smaller time. However, this direct proportionality converts into inverse proportionality for larger values of time. It is observed that the increase in the nanoparticles volume fraction causes an increase in temperature distribution. It is due to lower specific heat of nanoparticles and its higher thermal conductivity than that of the base fluid.

Does the likelihood of malignancy in thyroid nodules with RAS mutations increase in direct proportion with the allele frequency percentage?

BackgroundGenomic testing has enhanced pre-surgical decision making for cytologically indeterminate thyroid nodules, but there remains uncertainty regarding RAS mutations. The addition of extra genetic alterations to previous driver mutation panels has been shown to improve predictive value. This study aims to evaluate the relationship between the mutant allele frequency (AF) and likelihood of malignancy in thyroid nodules with RAS mutations.MethodsA retrospective cohort review was performed evaluating patients with indeterminate cytology (Bethesda categories III, IV and V) and ThyroSeq® v3 testing demonstrating a RAS mutation, who underwent surgery. Univariate and multivariate regression analyses were used to evaluate relationships between AF, other genetic alterations, and malignancy.ResultsThirty-nine patients met criteria, 77% of the thyroid nodules (30/39) were found to be malignant. None demonstrated aggressive pathology. On univariate regression, there was no relationship between AF and likelihood of malignancy. There was, however, a significant correlation between AF and the rate of an additional genetic alteration. Multivariate analysis found a trend between RAS, a second genetic alteration and malignancy, but it did not reach statistical significance.ConclusionsThere was no direct relationship between the level of allelic frequency in thyroid nodules expressing RAS mutations and the likelihood of malignancy. There was a statistically significant relationship between increasing AF and the presence of a second genetic abnormality, suggesting a possible progression from initial driver mutation and then a second genetic alteration prior to malignant transformation.Graphical abstract

On mechanics and monitoring of plunge-roll rotary dressing of grinding wheels

A study is made into the mechanics and monitoring of rotary plunge-roll dressing of grinding wheels using a roll with multi-layer diamonds contained in a hybrid, metal-ceramic bond. A fundamental relationship is obtained between grinding/dressing specific energy and the dressing aggressiveness number Aggrd, revealing a distinct size effect. Results also indicate (i) a nearly linear relationship between grinding and dressing specific energy, and (ii) direct proportionality between dressing specific energy and the acoustic emission (AE) signal. SEM observations indicate that smaller Aggrd produces a grit-dulling phenomenon different from grinding-induced dulling of the grits by attrition, which causes rapid workpiece-material adhesion.

The impact of liver iron overload determined by T2* MRI on liver fibrosis determined by FibroScan in patients with thalassemia major

Background:Thalassemia major (TM) is a form of hemolytic anemia requiring monthly blood transfusions from early childhood with each RBC introducing 200mg of iron to the patient system. The prognosis of liver iron overload is highly dependent on the one hand on both liver iron content (LIC) and the extent of liver fibrosis. In recent years, non-invasive methods were developed in order to replace liver biopsy. Magnetic resonance imaging (MRI) with T2*-weighted sequences has the potential to become a non-invasive standard technique in assessing tissue iron. Transient elastography TE (fibroScan) is a new non-invasive and reliable bedside method used to measure liver stiffness (LS) caused by fibrosis. Methods:This is a prospective study which was conducted on 40 patients diagnosed with a β-thalassemia major (22 males and 18 females) with age from 6 to 16 years old, regular blood transfusion and Iron chelation therapy for at least 18 months. All patients underwent evaluation of clinical manifestations, laboratory investigations and MR imaging techniques: liver to muscle signal intensity ratio and T2* and R2* Relaxometry. Results: R2* was significantly higher among sever iron overload stage than the other stages. T2* is reverse proportion with iron overload, but R2* is direct proportion with iron overload in liver. Age was significantly increased among severe iron overload group than mild and moderate groups. Also, there was significant relation between consanguinity and family history with iron overload stages among the studied patients. Virus C and splenectomy were significantly higher among severe iron overload stage than mild and moderate stages. Also, age at diagnosis was significantly higher among moderate iron overload stage than the other stages. There was highly significant relation between iron overload stages and fibrosis stage Also, Fibrosis reading was significantly higher among moderate iron overload stage than the other stages. Conclusions: MRI T2* is the best noninvasive method for assessment and evaluation of hepatic iron overload and determine its severity in β thalassemic major patients. There was significant relation between iron overload stages with MRI T2* and R2*