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Few studies analysed the impact of different venous resection techniques on recurrence in patients with pancreatic ductal adenocarcinoma (PDAC). Primary aim was to compare local recurrence rate and disease-free survival (DFS) between patients who underwent pancreatectomy with tangential versus segmental resection of portal vein/superior mesenteric vein. All consecutive patients who underwent pancreatectomy with venous resection for PDAC between 2009 and 2019 were included. A propensity score matching (PSM) was used to reduce the effect of treatment selection bias. Overall, 120 patients (68%) underwent pancreatectomy with tangential venous resection and 57 patients (32%) were submitted to pancreatectomy with segmental venous resection. After a median follow-up of 24 months, local recurrence was comparable between the two groups (tangential: n = 32/120, 26.7% versus segmental: n = 10/57, 17.5%; p = 0.58). The median DFS was 17 months (IQR 9–31) in patients who underwent tangential resection, as compared to 12 months (IQR 5–21) in those who underwent segmental resection (p = 0.049). After PSM (n = 106), the median DFS was 18 months (IQR 9–26) in the tangential resection group, and 12 months (IQR 5–21) in the segmental resection group (p = 0.17). In the PSM population, lymph node ratio (HR 4.83; p = 0.028) and tumor size >25 mm (HR 3.26; p = 0.007) were identified as determinants of local recurrence. Tangential venous resections are not associated with a higher rate of local recurrence. Long-term outcomes are more related to tumors characteristics than to venous resection techniques. A step-up approach to vein resection, with tangential resection being performed whenever technically feasible, should be strongly encouraged. • Tangential vein resections are not associated with higher rates of local recurrence • Long-term outcomes are similar between tangential versus segmental venous resection • Tumor features rather than vein resection techniques affect survival outcomes • Tangential vein resections are associated with lower postoperative complications • Tangential vein resections should be preferred, whenever technically feasible [ABSTRACT FROM AUTHOR]

Microsurgical resection of medial temporal brain arteriovenous malformations (AVMs) is typically conducted through 2 approaches: the orbitozygomatic-tangential and subtemporal-transcortical. Relative indications and outcomes for these techniques have not been formally compared. The cerebrovascular database of a quaternary center was reviewed for patients with medial temporal AVMs treated between January 1, 1997, and July 31, 2021. Demographic characteristics, lesion characteristics, surgical approaches, and outcomes were retrospectively analyzed and compared. Postoperative outcome testing was performed using the Montreal Cognitive Assessment and Global Quality of Life Scale. Fifty-nine patients were assessed. Mean (standard deviation) age was 31 (18) years; 30 (51%) patients were male. Of the AVMs, 29 (49%) were left-sided and 30 (51%) were right-sided. The tangential approach was selected in 20 (34%) cases, whereas the transcortical technique was preferred in 39 (66%). Improved modified Rankin Scale status was significantly associated with the tangential resection technique both in the early postoperative period (P = 0.02) and at last follow-up (P = 0.01). Differences between the tangential and transcortical approaches were not significant with respect to new postoperative deficits (5/20 [25%] vs. 12/39 [31%], P = 0.87) or the presence of residual AVM on follow-up angiography (1/20 [6%] vs. 5/39 [14%], P = 0.65). The orbitozygomatic-tangential strategy was associated with favorable functional and quality-of-life outcomes after medial temporal AVM resection. These benefits are likely to be attributable to minimization of temporal retraction, avoidance of brain transgression, and avoidance of traction on the vein of Labbé, rendering the orbitozygomatic-tangential approach the preferred option for cases that are anatomically amenable to either strategy. [ABSTRACT FROM AUTHOR]

• ViTAT mimics the dose distribution of tangential fields (TF) plans. • Using 20° sectors of four arcs is needed to mimic the delivery of TF. • Better PTV homogeneity and lower dose to contralateral OARs are obtained. • Mean dose to ipsilateral OARs are unchanged; body integral dose reduced. • ViTAT may translate KB-models based on TF data into efficient automatic planning. To test the performances of a volumetric arc technique named ViTAT (Virtual Tangential-fields Arc Therapy) mimicking tangential field irradiation for whole breast radiotherapy. ViTAT plans consisted in 4 arcs whose starting/ending position were established based on gantry angle distribution of clinical plans for right and left-breast. The arcs were completely blocked excluding the first and last 20°. Different virtual bolus densities and thicknesses were preliminarily evaluated to obtain the best plan performances. For 40 patients with tumor laterality equally divided between right and left sides, ViTAT plans were optimized considering the clinical DVHs for OARs (resulting from tangential field manual planning) to constrain them: ViTAT plans were compared with the clinical tangential-fields in terms of DVH parameters for both PTV and OARs. Distal angle values were suggested in the ranges [220°,240°] for the right-breast and [115°,135°] for the left-breast cases; medial angles were [60°,40°] for the right side and [295°,315°] for the left side, limiting the risk of collision. The optimal virtual bolus had −500 HU density and 1.5 cm thickness. ViTAT plans generated dose distributions very similar to the tangential-field plans, with significantly improved PTV homogeneity. The mean doses of ipsilateral OARs were comparable between the two techniques with minor increase of the low-dose spread in the range 2–15 Gy (few % volume); contralateral OARs were slightly better spared with ViTAT. ViTAT dose distributions were similar to tangential-fields. ViTAT should allow automatic plan optimization by developing knowledge-based DVH prediction models of patients treated with tangential-fields. [ABSTRACT FROM AUTHOR]

To clarify or interpret the measurement results of double-flank gear measurement (DFGM), the mathematical model of radial and tangential error analysis of double-flank gear measurement is established. Using differential method, the mathematical model of surface-to-surface contact stage is concerned, and also the tip-to-surface interference stage is involved. The error sources including the base radius error (or profile slope deviation) and the tooth space angle error (or single pitch deviation) of the gear to be measured are concerned. A case study of the gear parameter with the gear contact ratio 1.77 is discussed to explain the tooth contact process, in which the critical contact points are listed for determining the rotation angle. The radial and tangential composite deviations are simulated under different sign combination or different value of the error sources to cover as many results as possible. The simulation results are compared with the measurement results on a gear measuring device (GMD) using double flank rack probe (DFRP), whereby the simulation parameters are determined through the gear profile slope deviation and the single pitch deviation of the gear measured on a Gear Measuring Center Klingelnberg P26. The curves of the simulation results and the measurement results on GMD are consistent to each other. For gear grade 6 according to ISO 1328-1:2013, the allowable value of the total profile deviation is 11.5 μm. The simulation results are compared with the measurement results on a gear measuring device (GMD) based on double flank rack probe (DFRP). The difference between the peak to peak value of the simulation results and the mean line of the measurement results within the evaluation range is 1 μm in radial direction and 1.3 μm in tangential direction, which means the simulation results has better consistency with the measurement results. The radial and tangential error analysis of DFGM can not only be used in simulation of the results, but also in interpreting the DFGM measurement results, which is helpful for gear measurement and quality control. [ABSTRACT FROM AUTHOR]

Tornadoes are generally defined as rotating columns of air characterized by small size, axisymmetry and short duration. Thus, the nature of tornadic wind load is basically different from that of synoptic wind. As direct measurements of velocities are very difficult and limited, lots of empirical and theoretical expressions of tornadic wind have been proposed. In the present study, characteristics of several numerical expressions were investigated, and it was found that the characteristics of velocity fields vary widely from model to model, making it difficult to choose one that is generally applicable. [ABSTRACT FROM AUTHOR]

Modeling fracture with a cohesive zone model requires an appropriate cohesive law for correlating interfacial tractions and crack face separation, especially in mixed-mode loading scenarios. Various approaches have been employed in order to develop such a law which can be characterized into potential-based and non-potential-based formulations. A critical re-examination of these methods is presented here, followed by a novel mixed-mode formulation which satisfies a physical criterion for crack propagation. Specifically, as the crack propagates, the trailing current crack tip is defined through the vanishing of normal and tangential components of the interfacial tractions simultaneously. A general formulation for mixed-mode conditions is proposed in this paper. In particular, given normal and tangential traction separation laws for pure normal and tangential modes as being material properties, the normal and tangential traction separation laws in mixed-mode loading are formulated so that all traction components disappear at the same effective separation when the crack advances. The new mixed-mode law is used to analyze three standard fracture problems in laminated composites, including double cantilever beam (DCB), end-notch flexure (ENF), and mixed-mode bending (MMB). A comparison with predictions from some selected mixed-mode cohesive laws and experimental data available in the literature is also included to further validate the proposed mixed-mode law. [ABSTRACT FROM AUTHOR]

Abstract: The development of tactile sensors and its data processing are crucial to advance robotics for allowing robots to explore and handle objects. Robots must sense the tactile feelings caused by contact between their hands and a human. This paper presents an influence of the stochastic resonance (SR) on tactile sensation that can enhance sensitivity by superimposing proper noise upon otherwise undetectable weak signals to detect the target signals. To investigate the SR of human tactile sensation and elucidate the mechanism of tactile SR, we performed a sequence of psychophysical experiments applying tangential directional vibration with a size of 2.5mm and 8mm stimulus point. We examined the difference threshold (DL) variation obtained from these experiments to clarify which condition of vibration direction and stimulus size causes the strongest SR. Furthermore we compared these results of tangential stimulus with results of normal stimulus obtained from our prior study. The experimental results show that neither normal nor tangential DL is significantly affected by stimulus point size. Moreover, tactile sensing precision is enhanced by appropriate noise and the characteristics of SR with tangential stimulation are quite different from those with normal stimulation. [Copyright &y& Elsevier]

Abstract: Circulating Fluidized Bed with gas-solid phases flow was set up in this paper. The gas and solid two phases flow and distribution of particle concentration in the tangential swirl/straight composite fluidized desulphurization tower was measured by Laser Doppler Particle Dynamic Analyzer(PDA). The results indicate that the axial velocity is high at the centre and low near the wall at the bottom of desulphurization tower, where the particle concentration has opposite situation, which forms typical annular-core flowing characters. At the range from 0.7R to 1.0R of the wall on the bottom of desulphurization tower, it forms stable rotational flow field and particle suspension layer. The space in the tower can be divided into three parts, straight flow zone at the centre, particle suspension zone and reflux zone close to the surface. The stable inner circulation of the materials generated. When swirl inlet is half closed, the circulation effect is reduced and the high concentration near the wall is decreased. With drop of the velocity inside, the particles settled obviously and its concentration increases. [Copyright &y& Elsevier]

Purpose: To present an automated technique for two-field tangential breast intensity-modulated radiotherapy (IMRT) treatment planning. Method and Materials: A total of 158 planned patients with Stage 0, I, and II breast cancer treated using whole-breast IMRT were retrospectively replanned using automated treatment planning tools. The tools developed are integrated into the existing clinical treatment planning system (Pinnacle3) and are designed to perform the manual volume delineation, beam placement, and IMRT treatment planning steps carried out by the treatment planning radiation therapist. The automated algorithm, using only the radio-opaque markers placed at CT simulation as inputs, optimizes the tangential beam parameters to geometrically minimize the amount of lung and heart treated while covering the whole-breast volume. The IMRT parameters are optimized according to the automatically delineated whole-breast volume. Results: The mean time to generate a complete treatment plan was 6 min, 50 s ± 1 min 12 s. For the automated plans, 157 of 158 plans (99%) were deemed clinically acceptable, and 138 of 158 plans (87%) were deemed clinically improved or equal to the corresponding clinical plan when reviewed in a randomized, double-blinded study by one experienced breast radiation oncologist. In addition, overall the automated plans were dosimetrically equivalent to the clinical plans when scored for target coverage and lung and heart doses. Conclusion: We have developed robust and efficient automated tools for fully inversed planned tangential breast IMRT planning that can be readily integrated into clinical practice. The tools produce clinically acceptable plans using only the common anatomic landmarks from the CT simulation process as an input. We anticipate the tools will improve patient access to high-quality IMRT treatment by simplifying the planning process and will reduce the effort and cost of incorporating more advanced planning into clinical practice. [Copyright &y& Elsevier]

Abstracts: Hydrodynamics of a gas–solid rotating bed reactor (RBR) in static geometry are investigated. Tangential injection of a gas at mass flow rate of 0.4–1kg/s in a cylindrical vessel with a diameter of 0.54m generates a rotating gas phase flow field. Introduction of solid particles in this field results into an annular dense gas–solid rotating bed. A stable annular gas–solid rotating bed without solids particles loss is achieved over a wide range of operating conditions. Goal of the presented work is to investigate, by means of experiments, the window for a stable operation of the gas–solid RBR, as a function of the solid particle diameter and density, the geometry of the RBR and the gas flow rate. If the solid particle diameter is comparable to tangential gas injection slot width, the establishment of a stable flow is delayed due to an increased slugging tendency. The upper limit of the solids content is found to decrease with decreasing solid particle diameter. Obtained experimental cold flow results are the initial steps in assessing the potentials of a RBR as an efficient gas–solid processing reactor from a process intensification point of view. [ABSTRACT FROM AUTHOR]

Abstract: A consideration of handwriting demonstrates that motions can be remarkably constant, even when performed with different effectors. Nevertheless, the transposition of writing from horizontal to vertical orientations, as occurs when writing on blackboards, poses additional problems for the constraint of movement. Motions in horizontal and vertical planes potentially challenge the mechanisms responsible for motor constancy. Gravitational fields impose different accelerative forces on vertical (up/down) compared with horizontal (left/right) motions. A 1/3 power law linking tangential velocity and radius of curvature is sometimes invoked to explain how equivalent motions can be performed by different effectors. To evaluate the operation of the power law when movements are performed in different orientations, 12 participants drew ellipses in horizontal and vertical planes at about 1 or 2Hz. Mean tangential velocity, radius of curvature and the strength of the 1/3 power law were analyzed. The power law was strongest for curved motions at faster speeds. The power law was weakest at slower speeds in the vertical orientation. As participants controlled their movement periodicity, this placed tighter constraints upon curvature in the vertical orientations than the horizontal orientations. Speed of motion had a greater effect upon curvatures in the horizontal than the vertical orientation. The data offer insights into variations in the strength of the power law under different orientations, and indicate a limited role for the 1/3 power law in motor constancy. [Copyright &y& Elsevier]

Abstract: The majority of cortical and hippocampal interneurons originate in the subcortical telencephalon and migrate tangentially into pallial regions before settling in various cortical layers. The molecular cues that regulate final positioning of specific interneurons in cortical structures have not yet been identified. The positioning of radially migrating principal neurons of the cortex and hippocampus depends upon Reelin, an extracellular protein expressed near the pial surface during embryonic development that is absent in reeler mutant mice. To determine whether the layer specification of interneurons, like that of principal neurons, requires Reelin, we crossed reeler with transgenic mice that contain Green Fluorescent Protein (GFP)-expressing Inhibitory Neurons (GINs). These neurons express basal forebrain markers Dlx1/2 in normal and reeler mice. In normal mice, GINs express Reelin and are localized to specific layers of the cortex and hippocampus. In reeler mutant mice, we show that GINs migrate normally into the pallium, but fail to acquire proper layer position. Double labeling experiments indicate that the neurochemical profile of these interneurons is not generally altered in reeler mice. However, the extension of their cellular processes is abnormal. Quantitative analysis of GINs in the cortex revealed that they are hypertrophic, bearing longer neuritic branches than normal. Thus, the lack of Reelin signaling results in abnormal positioning and altered morphology of forebrain interneurons. [Copyright &y& Elsevier]

Although rare, blast injury to the intestine can result from penetrating thoraco-abdominal extra-peritoneal gunshot (and shotgun) wounds despite the absence of injury to the diaphragm or to the peritoneum. Injuries of the spleen, small intestine and the mesentery by this mechanism have been previously reported in the world literature. This paper reports the first two cases of non-penetrating ballistic trauma to the colon. [Copyright &y& Elsevier]

Background and purpose: The dose variation throughout the volume of the breast from tangential fields can exceed 20% for large breasts. This is postulated to result in poor cosmesis [Radiother Oncol 16 (1989) 253], particularly at the inframammary fold, where the dose is highest. Compensators may be used to reduce this variation, but at the cost of the time to manufacture each unique compensator for the individual patients. This paper outlines the implementation and routine use of a library of reusable compensators.Materials and methods: For the period of December 1999 to May 2001, 94 patients attending for breast radiotherapy received treatment using breast compensators calculated from multiple outlines measured using the Osiris system. The compensators manufactured for the early patients were added to a library for possible reuse by later patients. Of the 94 patients, 28 patients’ compensators formed the library and 66 subsequent patients have been treated using compensators derived from the library. Selection of the most appropriate library compensator was determined from the analysis of the distribution of the calculated dose-volume histogram for the whole breast, excluding lung, penumbra and build-up regions. Once the library was complete, approximately 50% of all subsequent breast patients were treated with compensators (46% from the library and 4% with individual compensators). This represented a usage rate of 92% for the library compensators for those patients requiring compensation.Results: In all cases the compensators reduced the variation in the dose distribution. For example, the group treated with a library compensator demonstrated a mean reduction from 29 to 9% for the volume of breast tissue receiving more than 5% greater than the reference dose. If the same patients had been treated using their own individual compensators, the corresponding value would have been 7%. There is a small systematic, but negligible, difference in the two populations of dose variation for individual versus library compensators, but this difference (P=0.20) did not reach the level of statistical significance of P=0.05).Conclusion: The method of creation and selection of library compensators has proved to be simple and reliable in practice. Every patient receiving radiotherapy for breast cancer is currently investigated under full software control to ascertain whether the use of a library compensator would be advantageous. [Copyright &y& Elsevier]

• The nozzle axes were tangential to a horizontal cylinder to form staggered vortexes. • The flow perpendicular to central-plane between two sidewalls was strengthened. • The best performance was achieved when θ = 22.1° and d/D = 0.34. • Flashlight frequency and CO 2 fixation rate increased by 90.9% and by 30%. A novel three-dimensional tangential swirl plate (TTSP) photobioreactor was proposed to strengthen flow perpendicular to central cross-section between two side walls, resulting in more widespread turbulence for improving microalgal CO 2 fixation. The axes of four center-symmetrically arranged nozzles were tangential to a horizontal cylinder to form two staggered vortexes. When angle θ between nozzle axis and central cross-section increased from 0° to 22.1° and then to 40.0°, mixing time and average bubble diameter first decreased to the minimum (16.55 s and 0.57 mm) and then increased. When relative diameter of tangential cylinder d/D increased from 0.11 to 0.34 and then to 0.56, flashlight frequency and light time ratio first increased to the maximum (0.21 Hz and 42.8%) and then decreased. Accordingly, flashlight frequency was 90.9% higher in TTSP photobioreactor than that in two-dimensional jet-aerated tangential swirl plate (JTSP) photobioreactor, leading to an increase in microalgal CO 2 fixation rate by 30%. [ABSTRACT FROM AUTHOR]

Abstract: The dose received by the sentinel node (SN) volume during tangential irradiation was studied on 31 patients. Of the 50Gy prescribed to the breast volume 95% of the SN volume received from 6.9 to 27.5Gy. In 19 patients the SN volume overlapped with the tangential field deep side. [Copyright &y& Elsevier]