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Laser micro-texture preparation technology significantly excels in micro-texture processing, yet there has been scant reported research on utilizing this technology for micro-texture processing and texture morphology control on the surface of wheat mill rolls. The aim was to ascertain the ideal laser preparation process parameters for the creation of groove-shaped micro-textures on the surface of the chilled alloy cast iron, serving as the surface layer material of the wheat mill roll. An experiment was conducted using a nanosecond pulsed fiber laser to explore the impact of laser power, scanning times, scanning velocity, and pulse frequency on the morphology and dimensions of the groove-shaped micro-textures. It was found that with laser power set at 7 W, 15 scanning times, a pulse frequency of 35 kHz, and a scanning speed of 500 mm/s, the desired microgroove can be successfully fabricated on the surface of the mill roll. The findings of this study offer insights for the surface modification of critical components in grain and oil machinery and equipment through the application of laser micro-texturing technology.Article Highlights: Application of laser micro-texturing technology to surface modification of key components of flour milling equipment. The effect of laser processing parameters on the surface groove micro-texture of chilled alloy cast iron was analyzed. Determination of optimal laser process parameters for the preparation of Groove-shaped micro-texture on the surface of mill roll. [ABSTRACT FROM AUTHOR]

Abstract Laser micro-texture preparation technology significantly excels in micro-texture processing, yet there has been scant reported research on utilizing this technology for micro-texture processing and texture morphology control on the surface of wheat mill rolls. The aim was to ascertain the ideal laser preparation process parameters for the creation of groove-shaped micro-textures on the surface of the chilled alloy cast iron, serving as the surface layer material of the wheat mill roll. An experiment was conducted using a nanosecond pulsed fiber laser to explore the impact of laser power, scanning times, scanning velocity, and pulse frequency on the morphology and dimensions of the groove-shaped micro-textures. It was found that with laser power set at 7 W, 15 scanning times, a pulse frequency of 35 kHz, and a scanning speed of 500 mm/s, the desired microgroove can be successfully fabricated on the surface of the mill roll. The findings of this study offer insights for the surface modification of critical components in grain and oil machinery and equipment through the application of laser micro-texturing technology.

Background: The incidence of non-palpable breast cancer is increasing due to widespread screening and neo-adjuvant therapies. Among the available tumor localization techniques, radio-guided occult lesion localization (ROLL) has largely replaced wire-guided localization (WGL). The aim of this study was to compare the ROLL and WGL techniques in terms of the effectiveness of isotopic marking of axillary sentinel lymph nodes and to assess patient perspectives along with surgeon and radiologist preferences. Methods: A single-center, prospective, randomized study enrolled 110 patients with non-palpable breast lesions (56 ROLL, 54 WGL). Breast type, tumor volume, location, histological and radiological features, and localization/surgical duration were evaluated in the context of sentinel lymph node marking using isotope (technetium-99m-labeled human serum albumin) and blue dye. Statistical analysis was performed with significance set at p < 0.05 and strong significance at p < 0.01. Results: A single-center, prospective, randomized study enrolled 110 patients with non-palpable breast lesions (56 ROLL, 54 WGL). Breast type, tumor volume, location, histological and radiological features, and localization/surgical duration were evaluated in the context of sentinel lymph node marking using isotope (technetium-99m-labeled human serum albumin) and blue dye. Statistical analysis was performed with significance set at p < 0.05 and strong significance at p < 0.01. Conclusions: While ROLL provided advantages in terms of patient comfort and logistical simplicity, WGL was superior for axillary sentinel lymph node marking, particularly in inner quadrant tumors, suggesting that WGL may be preferred in these cases. [ABSTRACT FROM AUTHOR]

Linear guides are essential components of precision equipment, such as computer numerical control machine tools and coordinate measuring machines. The key to improving their accuracy is to conduct high-precision measurements and effectively compensate for the six degrees of freedom errors that emerge during motion. However, the roll is a difficult parameter for achieving high-precision measurements in laser measurements, and it has yet to be effectively addressed. This study presents a high-precision and high-sensitivity roll measurement method based on the laser polarization state. The method employs a quarter-wave plate as the roll angle sensitive component. Firstly, the feasibility of this method was assessed through the Jones matrix and Zemax simulations. Subsequently, both theoretical and experimental analyses were conducted to evaluate the impact of using a corner cube reflector as a retroreflector on roll measurements. Finally, a corresponding measurement device was developed, and a series of comprehensive experiments were executed. The experimental findings indicate a measurement sensitivity of 7 mV/arcsec for this method. In comparison to commercial autocollimators, the contrast deviation within ± 100 arcsec is ± 1 arcsec. The repeatability of measurements on the air-floating guide rail is 1.3 arcsec, with a maximum contrast deviation of 2.5 arcsec compared to the electronic level. Thus, the proposed method offers the advantages of high precision, simple structure, and low cost and provides a new technique for high-precision roll measurement. [ABSTRACT FROM AUTHOR]

Purpose: Intraoperative identification and excision of specific lymphadenopathies is not always easy; it is, therefore, important to have complementary techniques that help us in the identification of these structures intraoperatively. The aim of this study is to present preliminary results of the use of ROLL technique (radioguided occult lesion localisation) as a method of excisional biopsy in the head and neck territory. Material and methods: We present 10 cases of patients with difficult to localise lymphadenopathies in the head and neck territory that underwent the ROLL technique. The radiotracer was only injected in the nodes that we wanted to study; in this way, all of them were correctly identified and extracted without resecting those that had no signs of pathology avoiding removing healthy lymphatic tissue and reducing morbidity. Results: The ROLL technique is a useful technique, since in all of the patients, the previously marked adenopathy was accurately identified and excised; we reduced the intraoperative time and avoided the complications derived from more aggressive cervical exploratory surgeries. [ABSTRACT FROM AUTHOR]

Aims: To assess whether impaired vestibular perception of self‐motion is a risk factor for unsteadiness and falls in elderly patients with type 2 diabetes (T2D). Materials and methods: 113 participants (65–75 years old) with T2D underwent tests of roll and pitch discrimination, postural stability (Berg Balance Scale, Modified Romberg Test, and quantitative posturography), clinical examination and blood chemistry analyses. Falls 1‐year after enrolment were self‐reported. We performed cluster analysis based on the values of the vestibular motion thresholds, and logistic stepwise regression to compare the clinical‐biochemical parameters between clusters. Results: We identified two clusters (VC1 n = 65 and VC2 n = 48 participants). VC2 had significantly (p < 0.001) higher (poorer) thresholds than VC1: mean pitch threshold 1.62°/s (95% CI 1.48–1.78) in VC2 and 0.91°/s (95% CI 0.84–0.98) in VC1, mean roll threshold 1.34°/s (95% CI 1.21–1.48) in VC2 and 0.69°/s (95% CI 0.64–0.74) in VC1. Diabetes duration was significantly (p = 0.024) longer in VC2 (11.96 years, 95% CI 9.23–14.68) than in VC1 (8.37 years, 95% CI 6.85–9.88). Glycaemic control was significantly (p = 0.014) poorer in VC2 (mean HbA1c 6.74%, 95% CI 6.47–7.06) than in VC1 (mean HbA1c 6.34%, 95% CI 6.16–6.53). VC2 had a significantly higher incidence of postural instability than VC1, with a higher risk of failing the Modified Romberg Test C4 (RR = 1.57, χ2 = 5.33, p = 0.021), reporting falls during follow‐up (RR = 11.48, χ2 = 9.40, p = 0.002), and greater postural sway in the medio‐lateral direction (p < 0.025). Conclusions: Assessing vestibular motion thresholds identifies individuals with T2D at risk of postural instability due to altered motion perception and guides vestibular rehabilitation. [ABSTRACT FROM AUTHOR]

In hot rolling mills, failure of work rolls is a major concern as it adversely affects mill operations and impacts production. These rolls fracture or spall due to many different reasons. Analysis of failed or spalled roll materials and actual rolling conditions in service are therefore necessary to understand the roll failure mechanism. The hot strip mill referred here consists of two stands in a roughing mill and seven stands in a finishing mill. HSS cast iron rolls are used in the primary strands of finishing mill for the rolling of cast slabs into HR sheets. This present case study describes the spalling of one of the finishing stand non-forged work rolls, and the analysis carried out using destructive as well as non-destructive testing techniques. The spalled roll showed fatigue arrest marks in a smooth continuous path along the circumferential direction. Characteristic features of the fracture surface were like those of surface-initiated spalling which is known as ribbon fatigue spalling. The fracture or spalled region was analysed using ultrasonic tests to identify the origin of the crack. A sample was also collected from the crack origination location where multiple cracks/fire cracks were observed. A detail micro-structural as well as SEM/EDS characterization of the fire cracks was done to understand the mechanism of spalling. The analysis revealed that fire cracks originated from the development of localized thermal stresses on the roll surface. These cracks resulted the roll spalling in operation. [ABSTRACT FROM AUTHOR]

Rolling is a natural behavior of equids that is beneficial to their well-being. However, more intensive domestic environments offer fewer opportunities for animals to roll, neglecting its importance. We believe that the inclusion of recreational areas for animals, containing substrates and conditions that encourage the occurrence of natural behaviors, is essential to promote their well-being. Therefore, we evaluated the preference of horses (Equus caballus; n = 8) and mules (E. asinus x E. caballus; n = 8) for different rolling substrates (sand, grass, manure), and the influence of this behavior on thermoregulation after exercise. Horses rolled preferentially on grass, whereas mules preferred sand, both of which were cooler substrates when compared to manure. In addition, the temperature of the animals significantly reduced after rolling. Thus, horses and mules must roll for thermoregulation after exercise, choosing cooler and more efficient substrates for heat dissipation. The differences in preferences between mules and horses showed particularities between the equine species and its hybrid, which is important for management that is focused more on the individual animal. [ABSTRACT FROM AUTHOR]

Aromatic polyimide films are widely used in high-tech fields due to their excellent combination of thermal, mechanical, and electrical properties. These films serve as precursors for the preparation of high thermal conductivity graphite films, with carbon content up to 70%, exhibits exceptional thermal and electrical conductivity, making it a promising precursor for polymer-based graphite films. This study focuses on the reserch of graphitization using commercial DuPont Kapton polyimide film. The polyimide film was rapped around a cylindrical mold and heat-treated at various temperatures. The impact of the process system on graphitization was thoroughly investigated, along with the evolution of polyimide's structure and properties during heat treatment. Results demonstrated that the size of the prepared films initially increased and then decreased with the increase in graphitization temperature. Additionally, the color of the prepared films transitioned from yellow-brown to black and eventually gray matte. The brittleness of the prepared films followed a similar pattern of initially increasing and then decreasing. When the temperature was below 2200 °C, the surface of the graphite films was smooth and defectless. However, at 2200 °C, small holes appeared on the surface, and at 2300 °C, the surface began to exhibit a "foaming" phenomenon, which intensified with temperature. XRD and Raman spectra analysis revealed that the degree of graphitization, crystallinity, and order of the prepared films increased with temperature. At 2800 °C, the sample achieved a theoretical degree of graphitization of 95.35% and a thermal conductivity of 1246.36 W/(m·K). [ABSTRACT FROM AUTHOR]

The required rail straightness is achieved by straightening with roller straighteners. The consequence of the straightening operation is the introduction of residual stresses to the straightened rail. An excessive level of residual stresses accumulated in the rail during use in the track may lead to its damage or fracture. ArcelorMittal Poland S.A., in cooperation with Łukasiewicz Research Network – Institute for Ferrous Metallurgy, carried out a research project (POI R.01.02.00-00-0167/16) the aim of which was to reduce residual stresses in railway rails by changing the technological parameters of the straightening process. The results of the presented study relate to rails 60E1 and 60E2. The study includes the measurement, testing, calculations and analyses of the obtained results. The conducted research indicates the possibility of obtaining a low level of residual stress in the rails for a system consisting of a 7-roller vertical straightener and a 9-roller horizontal straightener by changing the roller settings, the shape of the rollers, the shape of the rail foot and its curvature.

American writer Julia Peterkin (1880-1961) represents a downhill trajectory in terms of literary prominence, from the Pulitzer Prize for fiction in 1929 to obscurity now, almost 100 years later. For a few years in the 1920s and 1930s, Peterkin was one among few white American authors who wrote primarily about black American lives and experiences. She can be seen as a temporary ally in relation to the contemporary political and cultural situation of black America. This article focuses on Scarlet Sister Mary (1928), Peterkin's most famous and controversial novel, and explores what happened to her literary reputation later, in the historical context of the early 1930s and in connection with the publication of Roll, Jordan, Roll (1933). My claim is that Peterkin's work engages American history and American literary history from a specifically American point in time, post-plantation era and post-Hawthorne, that temporarily allows and even rewards the literary blackface and racial/racist oscillation of Peterkin as a poputchik writer, a fellow traveler in relation to black America. [ABSTRACT FROM AUTHOR]

The maximum diving depth of modern submarines has always been increasing. Although this has been useful and in some cases necessary, it usually comes with some risks. For instance, when a submarine encounters an emergency situation that requires immediate ascent from great depths, the situation becomes more dangerous, especially due to its rolling characteristics. To investigate the effect of unsteady forces during free ascent motion of submarines at great depths on submarine rolling, in this study, the SST-DDES model combined with the overset grid technique was used for the numerical simulation of a submarine free ascent. Water tank experiments for free ascent were conducted to validate the numerical approach, which confirmed the reliability of the numerical method. Following this, the CFD method was employed to conduct an initial exploratory investigation into the free ascent motion of deep-submergence submarines. The free ascent motion of submarines at great depths under five different degrees of freedom combinations was studied. The computational results indicated that submarines are more prone to roll over during free ascent at great depths. At a depth six times the length of the submarine, the maximum roll angle underwater reaches 22.8°. In addition, unsteady rolling moments, lateral forces, and yawing moments have a significant effect on submarine rolling, intensifying the tendency to roll. Furthermore, it was observed that the vertical hydrodynamic attack angle β is related to the rolling stability of the submarine, such that a moderate decrease in β is beneficial for the rolling stability. The numerical calculation method and preliminary research findings can provide theoretical support for controlling the ascent motion of real submarines. [ABSTRACT FROM AUTHOR]

Mange is a skin disease caused by mites that parasitize an animal's skin, often yielding inflamed immune responses and hair loss. At a population level, mange may reduce survival and cause population declines. Many forms of mange can be treated quite effectively when an animal is in hand; however, this is not often feasible for many free-ranging wildlife populations. Some animals, particularly territorial carnivores, will rub or roll to scent mark and transmit information about their presence to other individuals. We posited that rub stations comprised, in part, of anthelmintic medication and foreign scents that induce rubbing could be used to remotely treat mange in the wild. We deployed 39 rub stations containing lure and dye in Santa Monica Mountains National Recreation Area, Southern California, USA, October–November 2022. Carnivores rubbed or rolled at.97% of rub stations, with coyotes (Canis latrans), gray foxes (Urocyon cinereoargenteus), and bobcats (Lynx rufus) being the most abundant species. Time to first rub or roll was generally <1 wk. Several sympatric species (e.g., mule deer, Odocoileus hemionus) were detected at rub stations but did not rub. Our pilot test provides strong evidence that treating mange in wild carnivores may be possible using the remote medicinal rub stations we describe. Future efforts to add medicine to rub stations and monitor for a change in mange prevalence are a logical next step. [ABSTRACT FROM AUTHOR]

Motion in waves is a crucial issue for planing craft safety and human comfort. Practically, a boat at sea may navigate in any heading angle with respect to wave directions. In this paper, the planing craft motion in regular oblique waves in a range of heading angles is investigated using computational fluid dynamics (CFD). The simulation is performed on two prismatic hulls in which slamming occurs on one hull, and the other one is in non-slamming condition. The simulation results are validated in comparison with the experiment in the head wave condition. Findings show that as the wave direction changes from the head to the oblique, heave, pitch and acceleration rapidly decrease while roll increases. Additionally, the impact acceleration becomes a quasi-periodic, and its amplitude drops at the same time. It is observed that the aforementioned influences are much more pronounced for the craft in slamming condition. [ABSTRACT FROM AUTHOR]

Background: The incidence of non-palpable breast cancer is increasing due to widespread screening and neo-adjuvant therapies. Among the available tumor localization techniques, radio-guided occult lesion localization (ROLL) has largely replaced wire-guided localization (WGL). The aim of this study was to compare the ROLL and WGL techniques in terms of the effectiveness of isotopic marking of axillary sentinel lymph nodes and to assess patient perspectives along with surgeon and radiologist preferences. Methods: A single-center, prospective, randomized study enrolled 110 patients with non-palpable breast lesions (56 ROLL, 54 WGL). Breast type, tumor volume, location, histological and radiological features, and localization/surgical duration were evaluated in the context of sentinel lymph node marking using isotope (technetium-99m-labeled human serum albumin) and blue dye. Statistical analysis was performed with significance set at p < 0.05 and strong significance at p < 0.01. Results: A single-center, prospective, randomized study enrolled 110 patients with non-palpable breast lesions (56 ROLL, 54 WGL). Breast type, tumor volume, location, histological and radiological features, and localization/surgical duration were evaluated in the context of sentinel lymph node marking using isotope (technetium-99m-labeled human serum albumin) and blue dye. Statistical analysis was performed with significance set at p < 0.05 and strong significance at p < 0.01. Conclusions: While ROLL provided advantages in terms of patient comfort and logistical simplicity, WGL was superior for axillary sentinel lymph node marking, particularly in inner quadrant tumors, suggesting that WGL may be preferred in these cases.

This study investigates the effects of sway and roll excitations on sloshing liquid loads in a tank, using Ansys Fluent software. The model considered in the study is a 1:50 scaled membrane-type tank, based on a KC-1 membrane LNG tank designed by Korea Gas Corporation (KOGAS). The volume of fluid (VOF) method is used to track the free surface inside the tank, and the standard k-ε model is applied to express the turbulent flow of the liquid. To explore the motion of the tank under excitation, a user-defined function (UDF) and a dynamic mesh technique are employed to control the external forces exerted on the tank through its motion. The results, in the form of time series data on the sloshing pressures in the tank under pure sway, roll, and coupled sway-roll, are analysed, with specific ranges for the excitation amplitudes and frequencies. We show that variations in excitation frequency and amplitude significantly influence the sloshing loads. Sloshing loads are found to intensify when the excitation frequency matches the tank’s primary natural frequency, 1.0 ω1′. Furthermore, with coupled sway-roll excitations, the sloshing loads are weakened when the sway and roll are in-phase and are intensified when these are out-of-phase. Fast Fourier transform analysis provides insights into the frequency domain, showing that the dominant frequency is 0.88 Hz and it is approximately equal to the tank’s primary natural frequency, 1.0 ω1′.

Mild traumatic brain injuries (mTBIs) continue to burden our warfighters. The high-tech industry has delivered wearable Micro-Electro-Mechanical System (MEMS) head-impact sensors to monitor impact forces. So far, these MEMS sensors have categorically failed to detect mTBIs and are therefore of no clinical utility for diagnosis. Our recent studies have shown that human head kinematics is anisotropic with respect to pitch–roll–yaw degrees of freedom of the head and neck. In the present project, we generated head acceleration datasets on non-injurious impacts and mTBI events based on mean values from the literature. We then augmented the simulated data with pitch–roll–yaw information followed by machine learning with a Classification and Regression Tree analysis. Our results revealed that head angular acceleration in pitch is the best predictor. More than 81.3 % of concussive injuries had head angular accelerations in pitch exceeding 3527 rad/s2. Out of 18.6% of concussive injuries with head angular accelerations in pitch under 3527 rad/s2, 75% of these cases had head angular accelerations in roll exceeding 1679 rad/s2. This study shows that artificial intelligence and machine learning should be able to provide accurate identification of subject-specific concussive thresholds in real time and in the field, thereby moving concussion diagnosis toward precision medicine. [ABSTRACT FROM AUTHOR]

The required rail straightness is achieved by straightening with roller straighteners. The consequence of the straightening operation is the introduction of residual stresses to the straightened rail. An excessive level of residual stresses accumulated in the rail during use in the track may lead to its damage or fracture. ArcelorMittal Poland S.A., in cooperation with Łukasiewicz Research Network - Institute for Ferrous Metallurgy, carried out a research project (POI R.01.02.00-00-0167/16) the aim of which was to reduce residual stresses in railway rails by changing the technological parameters of the straightening process. The results of the presented study relate to rails 60E1 and 60E2. The study includes the measurement, testing, calculations and analyses of the obtained results. The conducted research indicates the possibility of obtaining a low level of residual stress in the rails for a system consisting of a 7-roller vertical straightener and a 9-roller horizontal straightener by changing the roller settings, the shape of the rollers, the shape of the rail foot and its curvature. [ABSTRACT FROM AUTHOR]

Excessive vertical, roll, and pitch motions of the vehicle can cause discomfort for the driver and passengers. Mitigation of such motions can be done using active suspensions. In this paper, proportional-derivative controllers are used to reduce the vertical, roll, and pitch motions by using a 10 degree-of-freedom vehicle model. The vehicle model is verified by using CarSim for a double lane change maneuver. The verification results have showed that the vehicle model used in this study can emulate the motion of the vehicle model in CarSim. The proportional-derivative controllers are used to calculate the desired vehicle vertical force, roll moment, and pitch moment. These desired force and moments are converted into active suspension force inputs by using decoupling transformation. When the vehicle is given sine steer wave and braking torque inputs, the results have showed that the controllers can reduce the vertical, roll, and pitch motions considerably. [ABSTRACT FROM AUTHOR]

To research serious nonlinear coupling problems among aerodynamics, flight mechanics, and flight control during high maneuvers, a virtual flight testing platform has been developed for a large-scale, high-speed wind tunnel, based on the real physical environment, and it can significantly mitigate risks and reduce the costs of subsequent flight tests. The platform of virtual flight testing is composed of three-degrees-of-freedom model support, measuring devices for aerodynamic and motion parameters, a virtual flight control system, and a test model. It provides the ability to realistically simulate real maneuvers, investigate the coupling characteristics of unsteady aerodynamics and nonlinear flight dynamics, evaluate flight performance, and verify the flight control law. The typical test results of a pitch maneuver with open-loop and closed-loop control are presented, including a one-degree-of-freedom pitch motion and a two-degrees-of-freedom pitch and roll motion. The serious pitch and roll-coupled motion during a pitch maneuver at a high angle of attack is revealed, and the flight control law for decoupled control is successfully verified. The comparison of the test results and the flight data of a real pitch maneuver proves the reliability and capability of virtual flight testing. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Chongqing University of Technology (Natural Science) is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The loss of revenue or global loss in term of cost due to downtime conditions is always a concern for field operators. Prevailing wave conditions may suddenly appear during offloading operations, which will influence the overall process and may lead to downtime of operations. Severe weather can significantly impact downtime costs of offloading operations and cause a huge loss of revenue. This research work integrates the dynamic stability with downtime cost for LNG carrier in different location of Malaysian waters using real time metocean data. This study on downtime cost utilizes the real time and location-specific wave scatters, as well as limiting criteria of offloading in Malaysian waters. The dynamic roll stability of LNG carrier was investigated for ABS criteria in two depths of water at three real-time locations. Susceptible wave conditions had been identified along with downtime cost analysis. This domain of downtime cost study was further rendered into mathematical package in the form of graphical interfaces for field operators. This mathematical based graphical interface facilitates in predicting location-specific downtime cost charts and allows operator companies to determine the fiscal losses for different range of downtime days and various capacities of LNG carrier. Overall, this research contributes by linking dynamic stability with operating costs through real time metocean data in Malaysian waters. [ABSTRACT FROM AUTHOR]

Copyright of Steel Pipe is the property of Steel Pipe Magazine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background and Objectives: Wide local excision is a common procedure in the treatment of breast cancer. Wire-guided localisation (WGL) has been the gold standard for many years; however, several issues have been identified with this technique, and therefore, wire-free techniques have been developed. This scoping review synthesises the available literature comparing wire-guided localisation with the wire-free techniques used in breast-conserving cancer surgery. Materials and Methods: Multiple databases including Pubmed and MEDLINE were used to search articles between 1 January 2000 and 31 December 2022. Terms included "breast neoplasms", "margins of excision", and "reoperation". In total, 34/256 papers were selected for review. Comparisons were made between positive margins and re-excision rates of WGL with wire-free techniques including SAVI SCOUT, Magseed, ROLL, and RSL. Pooled p-values were calculated using chi-square testing to determine statistical significance. Results: Pooled analysis demonstrated statistically significant reductions in positive margins and re-excision rates when SAVI SCOUT, RSL, and ROLL were compared with WGL. When SAVI SCOUT was compared to WGL, there were fewer re-excisions {(8.6% vs. 18.8%; p = 0.0001) and positive margins (10.6% vs. 15.0%; p = 0.0105)}, respectively. This was also the case in the ROLL and RSL groups. When compared to WGL; lower re-excision rates and positive margins were noted {(12.6% vs. 20.8%; p = 0.0007), (17.0% vs. 22.9%; p = 0.0268)} for ROLL and for RSL, respectively {(6.8% vs. 14.9%),(12.36% vs. 21.4%) (p = 0.0001)}. Magseed localisation demonstrated lower rates of re-excision than WGL (13.44% vs. 15.42%; p = 0.0534), but the results were not statistically significant. Conclusions: SAVI SCOUT, Magseed, ROLL, and RSL techniques were reviewed. Pooled analysis indicates wire-free techniques, specifically SAVI SCOUT, ROLL, and RSL, provide statistically significant reductions in re-excision rates and positive margin rates compared to WGL. However, additional studies and systematic analysis are required to ascertain superiority between techniques. [ABSTRACT FROM AUTHOR]

The maximum diving depth of modern submarines has always been increasing. Although this has been useful and in some cases necessary, it usually comes with some risks. For instance, when a submarine encounters an emergency situation that requires immediate ascent from great depths, the situation becomes more dangerous, especially due to its rolling characteristics. To investigate the effect of unsteady forces during free ascent motion of submarines at great depths on submarine rolling, in this study, the SST-DDES model combined with the overset grid technique was used for the numerical simulation of a submarine free ascent. Water tank experiments for free ascent were conducted to validate the numerical approach, which confirmed the reliability of the numerical method. Following this, the CFD method was employed to conduct an initial exploratory investigation into the free ascent motion of deep-submergence submarines. The free ascent motion of submarines at great depths under five different degrees of freedom combinations was studied. The computational results indicated that submarines are more prone to roll over during free ascent at great depths. At a depth six times the length of the submarine, the maximum roll angle underwater reaches 22.8°. In addition, unsteady rolling moments, lateral forces, and yawing moments have a significant effect on submarine rolling, intensifying the tendency to roll. Furthermore, it was observed that the vertical hydrodynamic attack angle β is related to the rolling stability of the submarine, such that a moderate decrease in β is beneficial for the rolling stability. The numerical calculation method and preliminary research findings can provide theoretical support for controlling the ascent motion of real submarines.

Typically, an inertial navigation system (INS) is used to determine the position, speed, and orientation of an object moving relative to the earth's surface. The navigation information (position, speed and orientation) of an unmanned aerial vehicle (UAV) is needed to control its flight. Since the resistance of INS to interferences is very high, it is possible to ensure reliable flights in conditions of high-intensity noise. This article explores the principles of constructing inertial measurement units (IMU) that are part of the INS and indicates perspective directions for their development. Micro-electromechanical inertial measurement units were studied in this work, and functional and principal electrical circuits for connecting units of inertial measurements to the microcontroller were developed. The results of practical measurements of units without calibration and after calibration were obtained using the created laboratory device. Based on the obtained results, the necessity of sensor calibration was revealed, and accuracy was improved by performing calibration with the Kalman filter algorithm. The Kalman filter is the heart of the navigation system. In a low-cost system, IMU errors like bias, scale factor error and random walk noise dominate the INS error growth.

Commodity index rolling is treated as a natural experiment and an event study of order flow costs in a wide array of futures markets is conducted. The spread between nearby and deferred futures prices decreases significantly in the early and growth phases of financialization (1991–2011), with the spreads reversing back after rolling is completed. Spread impacts disappear in the post‐financialization period (2012–2019). We argue that a dramatic increase in the supply of liquidity brought on by the transition to electronic trading in commodity futures markets is primarily responsible for the decline of roll order flow costs. [ABSTRACT FROM AUTHOR]

Objetivo principal: comparar la efectividad para la comprobación de márgenes quirúrgicos entre SPECT portátil y la mamografía de la pieza (RxM). Objetivo secundario: estandarizar un protocolo preintraquirúrgico mediante SPECT portátil y evaluar el tiempo requerido en el uso de esta técnica. Estudio longitudinal prospectivo con 36 pacientes (39 lesiones) diagnosticadas de cáncer de mama con criterios para realización SNOLL/ROLL. Se realiza en estudio prequirúrgico de la lesión tumoral, tras la administración ecoguiada de [99mTc]Tc-nanocoloides de albúmina/[99mTc]Tc-macroagregados de albúmina, en la lesión tumoral. Mediante SPECT portátil se obtienen imágenes híbridas (óptico + SPECT) e imágenes de navegación en 3D con sonda gamma. En quirófano se obtienen 4-5 imágenes con SPECT portátil, I) sobre piel para localización tumoral II) tras exposición de lecho para guía de resección, III) del lecho tras exéresis, IV y V) a la pieza quirúrgica. Se decide ampliación o no de márgenes considerando tres criterios: a) actividad residual (cps) en bordes de resección del lecho; b) análisis visual de la captación en la pieza; c) una distancia mínima de 10 mm de los bordes de la pieza hasta el centro de mayor captación, más el radio de la lesión. En este estudio se valora la concordancia de: la medición de la profundidad entre ecografía y SPECT portátil en el estudio prequirúrgico; los márgenes quirúrgicos entre SPECT portátil vs. RxM, teniendo de técnica de referencia anatomía patológica (AP); del tiempo quirúrgico empleado con SPECT portátil. Localización intraquirófano: se realizó en todos los casos. El análisis de los resultados se realiza por cada uno de los bordes de cada lesión tumoral por separado. Falso negativo (FN: no detección borde afecto) con SPECT portátil: 9 bordes; con RxM: 8. Verdadero positivo (VP: detección borde afecto) con SPECT portátil: 5 bordes, con RxM: 6. Verdadero negativo (VN: considerar borde libre cuando es sano) con SPECT portátil: 213 bordes; con RxM: 196. Valor predictivo negativo (VPN: probabilidad de borde negativo en pieza sin borde afecto) con SPECT portátil: 95,9%, con RxM: 96,07%. Especificidad con SPECT portátil: 96,8%, con RxM: 97%. Concordancia de bordes de pieza quirúrgica entre SPECT portátil y RxM: 94,5%. Entre SPECT portátil y AP: 93,1%. Entre RxM y AP: 93,5%, todo ello siendo estadísticamente significativo (p valor < 0,001). Grado de correlación entre SPECT portátil y AP bajo (índice Kappa: 0,34 IC95% [0,22-0,47] y entre RxM y AP moderado (índice kappa: 0,42 IC95% [0,29-0,56], con p valor < 0,001. Confrontación de los aciertos y los fallos de ambas técnicas (SPECT portátil y RxM) y AP: distribución χ2: 0,023 con grado de libertad 1, con p-valor < 0,05, por lo que podemos afirmar que ambas técnicas son similares, ya que no hay diferencias estadísticas significativas. Mediana de tiempo total en quirófano: 60,25 minutos (30-145). Tiempo medio de uso SPECT-portátil intraquirófano: 5 rastreos=10 minutos. No hay diferencias estadísticamente significativas en la probabilidad para descartar márgenes afectos que requieren una segunda cirugía entre ambas técnicas (SPECT portátil y RxM) por lo que, la técnica realizada con SPECT portátil es un procedimiento útil y efectivo, que requiere un entrenamiento específico con un protocolo optimizado y multidisciplinar. El tiempo empleado con SPECT portátil es viable para la práctica diaria. Main objective: To compare the effectiveness for checking surgical margins between SPECT-portable and mammography of the piece (RxM). Secondary objective: To standardize a pre-operative protocol using SPECT-portable and to evaluate the time required in the use of this technique. Prospective longitudinal study with 36 patients (39 lesions) diagnosed with breast cancer (CM) with criteria for SNOLL/ROLL. A pre-surgical study of the tumor lesion was performed, after the eco-guided administration of 99mTc-nanocolloids of albumin/99mTc-macroaggregates of albumin, in the tumor lesion. Hybrid images (optical + SPECT) and 3D navigation images with gamma probe are obtained using freehandSPECT. In the operating room, 4–5 images are obtained with freehandSPECT, (I) on skin for tumor location, (II) after exposure of surgical bed for resection guide, (III) of the surgical bed after exeresis, (IV and V) the anterior–posterior and lateral surface of the surgical specimen. The three criteria to decide to extend the margins are: (a) residual activity (cps) at the edges of the surgical bed resection; (b) visual analysis of the uptake in the specimen; (c) a minimum distance of 10 mm from the edges of the specimen to the center of greatest uptake, plus the radius of the lesion. We study the concordance of: the depth measurement between ultrasound and freehandSPECT; the surgical margins between freehandSPECT vs. mammography of the specimen (RxM), considering anatomical pathology (AP) as the gold standard technique as reference; surgical time used with freehandSPECT and RxM. Intraoperative localization was performed in all cases. False negative (FN: no detection margin affected) with freehandSPECT: 9 margins; with RxM: 8. True positive (TP: detection margin affected) with freehandSPECT: 5 margins, with RxM: 6. True negative (TN: consider free margin when healthy) with freehandSPECT: 213 margins; with RxM: 196. Negative predictive value (NPV: probability of negative margin on unaffected part) with freehandSPECT: 95.9%, with RxM: 96.07%. Specificity with freehandSPECT: 96.8%, with RxM: 97%. The concordance of surgical bed margins between freehandSPECT and RxM: 94.5%. Between freehandSPECT and AP: 93.1%. Between RxM and PA: 93.5%, being all statistically significant (p -value <0.000), so we can affirm that both techniques are related or dependent on the reference technique, the PA. Degree of correlation between SPECT-portable and low PA (Kappa index: 0.34, 95% CI [0.22–0.47], and between RxM and moderate PA (Kappa index: 0.42, 95% CI [0.29–0.56], p -value <0.001. Comparison of the successes and failures of both techniques (SPECT-portable and RxM) and PA: Distribution χ2: 0.023 with degree of freedom 1, with value <0.05, so we can affirm that both techniques are similar, since there are no significant statistical differences. Median total OR time: 60.25 min (30–145). Mean freehandSPECT OR time: 5 scans = 10 min. There are no statistically significant differences in the probability to rule out affective margins that require a second surgery between both techniques (SPECT-portable and RxM) so, the technique performed with SPECT-Portable is a useful and effective procedure, which requires specific training with an optimized and multidisciplinary protocol. The time spent with SPECT-portable is feasible for daily practice. [ABSTRACT FROM AUTHOR]

Experienced ship roll during loading is the easiest parameter to observe and measure on board of a loaded ship. Therefore, the ship’s significant roll amplitudes should be the key limiting factor in view of the safety and efficiency of cargo handling operations at sea. For the example of three standard bulk carriers, the authors prepared a method of assessment of bulk carrier suitability to perform safe and efficient cargo handling operations in the Clarion-Clipperton Zone in view of significant amplitudes of roll. Via a calculation of the efficiency index for a set of limiting amplitudes of roll during loading simulation, we are able to analyze ship effectiveness. The application of the above-mentioned method can be employed as a useful tool to predict the lowest allowable significant amplitudes of roll when the required efficiency level is specified. Additionally, a calculation is made for the operable days where cargo operations are possible. Investigations show that, according to applied criteria, the effectiveness drops, and not every bulk carrier can perform safe cargo handling operations at sea. [ABSTRACT FROM AUTHOR]

As a guide rail is the basic motion unit of precision equipment, the measurement of and compensation for its motion errors are important preconditions for precision machining and manufacturing. A targetless and simultaneous measurement method of three-degree-of-freedom (3-DOF) angular motion errors using digital speckle pattern interferometry (DSPI) is introduced in this paper. Based on the analysis of the sensitivity mechanism of DSPI to DOF errors and the formation mechanism of the phase fringes, the relationship between the angular motion errors and the distribution of the interferometric phases was established, and a new simultaneous measurement model of 3-DOF angular motion errors was further proposed. An optical setup based on a three-dimensional spatial-carrier DSPI with a right-angle symmetrical layout was used in the measurement system. Furthermore, repetitive tests, noise tests, and precision analysis were carried out to verify the performance of the system. The test results showed that the measurement resolution of the system was <1 μrad, which is capable of measuring the pitch angle, yaw angle, and roll angle at the submicron arc level simultaneously without target mirrors. The method has the advantages of no need to install cooperative targets and high measurement resolution, showing broad application prospects in many fields, including mechanical manufacturing, laser detection, aerospace, etc. [ABSTRACT FROM AUTHOR]

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To research serious nonlinear coupling problems among aerodynamics, flight mechanics, and flight control during high maneuvers, a virtual flight testing platform has been developed for a large-scale, high-speed wind tunnel, based on the real physical environment, and it can significantly mitigate risks and reduce the costs of subsequent flight tests. The platform of virtual flight testing is composed of three-degrees-of-freedom model support, measuring devices for aerodynamic and motion parameters, a virtual flight control system, and a test model. It provides the ability to realistically simulate real maneuvers, investigate the coupling characteristics of unsteady aerodynamics and nonlinear flight dynamics, evaluate flight performance, and verify the flight control law. The typical test results of a pitch maneuver with open-loop and closed-loop control are presented, including a one-degree-of-freedom pitch motion and a two-degrees-of-freedom pitch and roll motion. The serious pitch and roll-coupled motion during a pitch maneuver at a high angle of attack is revealed, and the flight control law for decoupled control is successfully verified. The comparison of the test results and the flight data of a real pitch maneuver proves the reliability and capability of virtual flight testing.

Summary. Typically, an inertial navigation system (INS) is used to determine the position, speed, and orientation of an object moving relative to the earth's surface. The navigation information (position, speed and orientation) of an unmanned aerial vehicle (UAV) is needed to control its flight. Since the resistance of INS to interferences is very high, it is possible to ensure reliable flights in conditions of high-intensity noise. This article explores the principles of constructing inertial measurement units (IMU) that are part of the INS and indicates perspective directions for their development. Micro-electromechanical inertial measurement units were studied in this work, and functional and principal electrical circuits for connecting units of inertial measurements to the microcontroller were developed. The results of practical measurements of units without calibration and after calibration were obtained using the created laboratory device. Based on the obtained results, the necessity of sensor calibration was revealed, and accuracy was improved by performing calibration with the Kalman filter algorithm. The Kalman filter is the heart of the navigation system. In a low-cost system, IMU errors like bias, scale factor error and random walk noise dominate the INS error growth. [ABSTRACT FROM AUTHOR]

Some methods for determining small angular deviations have been considered on the example of building objects. The design of an electrostatic cylindrical sensor was put forward, and the use of force action of an electric field was proposed in order to increase the sensitivity of the sensor. The main structural elements of the sensor are a plumb-line weighted at one end and a cylinder surrounding it. The conditions of equilibrium and instability of the position of the plumb arising due to positive feedback in the electric field were considered. An estimated calculation of the time of movement of the plumb until the moment of its touching the inside of the cylinder was made. The calculation result could be taken as a starting point for finding the desired angular deviation. The inaccuracy in the manufacture of the device and the random factors were noted to become influential at small deviations. The paper proposed some ways to solve these problems.