Lateral Space Research Articles

Laparoscopic Uterine Artery Occlusion Combined with Uterine-sparing Pelvic Plexus Block and Partial Adenomyomectomy for Adenomyosis: A Video Case Report

OBJECTIVE Adenomyosis usually causes dysmenorrhea and anemia. Clinically, it is difficult to be solved by medicine and traditional surgery, and hysterectomy is always performed for radical treatment. In this article, we introduce a new method which could control the dysmenorrhea and anemia through laparoscopic uterine artery occlusion (LUAO) combined with uterine-sparing pelvic plexus block, and partial adenomyomectomy for uterus perservation.

The lateral meniscal extrusion after repair with concomitant anterior cruciate ligament reconstruction at a mean follow-up of 3.5 years

BackgroundA meniscal repair is often performed on radial/flap or longitudinal tears of the lateral meniscus (LM) combined with anterior cruciate ligament reconstruction (ACLR). However, it is unknown if meniscal extrusion changes over time after repair. This study evaluated whether meniscal extrusion of the LM is maintained after repair or progresses with time using magnetic resonance imaging (MRI). MethodsAmong 574 patients who underwent primary anatomic ACLR, 123 patients followed up for more than 2 years were retrospectively analyzed. Forty patients with concomitant radial/flap tears of the LM (group R), 43 with longitudinal LM tears (group L), and 40 with intact LM (group C, matched-control group) were included. Clinical findings (pain, range of motion, swelling, and anterior laxity), lateral joint space on radiograph, and meniscal extrusion on MRI were assessed. Lateral/posterior meniscal extrusions were examined preoperatively, within 3 weeks after surgery, and at the final follow-up, and the absolute values and relative values (the preoperative values as baseline) were assessed respectively. ResultsThere were no significant differences in the clinical and roentgenographic findings among the groups. No difference was observed in the relative values within 3 weeks after surgery among three groups, although the absolute values were larger in the repaired groups than in group C. At the final follow-up, however, the lateral extrusion in group L had progressed significantly, compared with that in group C (P = 0.033), while no significant difference was detected in the lateral extrusion between groups R and C (P = 0.177). The posterior extrusion in groups R and L had progressed significantly compared with that in group C (P < 0.001). ConclusionsLM extrusion could not be improved even immediately after meniscal repair, and it progressed laterally and posteriorly for more than 2 years after surgery.

Hydrodynamics of the swirling steam-water two-phase flows over a surface with protrusions: Shape optimization and effect of rise in temperature on drag reduction

The current study studies the drag reduction offered by the plate with protrusions to the swirling steam-water two-phase flows. Protrusions of different types, having triangular, sinusoidal, and trapezoidal shapes, are investigated. The variations and modifications were made in the dimensions and orientations (facing along or across, flush-mounted or protruded into the swirling flows), to test the effectivity of these protrusions. At 5 bars of inlet gauge pressure and rpm varying from 360 to 1440, the trapezoidal shape provides the most effective drag reduction. It is also found from the PIV images of the fluid region near the protrusions that the drag reduction in the trapezoidal-shaped protrusions occurs mainly due to the secondary flow structures formation over those protrusions.On the one hand, the lateral spacing between the adjacent protrusions created the region of strengthening and expansion against the higher opposite inertial forces from the main swirling core fluids. While on the other hand, these spacings justify the impact of the axial elongation of the vortices above the protrusion tips. Further trends in drag reduction have also been investigated by observing the effect of the rise in the temperature of the fluid medium. Reduction in drag from 1.3 to 1.6% is noted using the trapezoidal protrusions for a temperature rise of 25–60 °C. It is also observed that the drag reduction profiles show a rising trend under the influence of the rising Nusselt Number. This trend is attributed to the decrease in viscosity. Whereas under the influence of a rising Prandtl number, the drag reduction shows a decreasing trend, mainly attributed to the rise in the pressure drop at the boundary layers and the pressure drop due to the friction.

Type I interferon enhances γδ intraepithelial lymphocyte migratory behavior via CD47 upregulation

Abstract γδ intraepithelial lymphocytes (IEL) migrate along the basement membrane and into the lateral intracellular space (LIS) between adjacent intestinal epithelial cells (IEC) and is critical to limit microbial translocation across the barrier. Although activated γδ IELs produce interferon (IFN)-α, whether IFNα directly influences γδ IEL migratory behavior remains unknown. To test this, intravital microscopy was performed on GFP γδ T cell reporter mice treated with PBS or IFNα (1 μg, i.v., 3h). We found that γδ IEL track speed was increased 30% and migration into the LIS was enhanced by 75% in IFNα-treated mice compared to controls. To identify candidate genes involved in regulating γδ IEL motility, we performed RNAseq on γδ IELs isolated from control and IFNα-treated mice. As expected, IFNα induced IFN-stimulated gene expression including CD47 (3.5-fold increase), a transmembrane protein involved in neutrophil transepithelial migration. Stimulation of ex vivo cultured γδ IELs with IFNα resulted in a 3-fold increase in CD47 expression compared to unstimulated controls. Next, to investigate whether IFNα enhances γδ IEL motility in vitro, GFP γδ IELs were co-cultured with enteroids expressing membrane tdTomato and treated with 10ng/ml IFNα for 3h. IFNα increased γδ IEL speed (4.5±0.2 vs 3.4±0.2 μm/min; p&amp;lt;0.05) and displacement (47±3.0 μm vs 34±3.1, p&amp;lt;0.05) relative to untreated controls. Addition of anti-CD47 blocking antibody (MIAP301) abrogated the IFNα-mediated increase in γδ IEL migratory behavior. Taken together, these data demonstrate that IFNα enhances γδ IEL motility via a CD47-mediated mechanism, and suggests that CD47 may represent a conserved mechanism of leukocyte migration within the epithelial barrier.

Collision avoidance method of autonomous vehicle based on improved artificial potential field algorithm

Both emergency braking and active steering are possible choices for collision avoidance manoeuvres, and any obstacle avoidance strategy aims to design a control algorithm preventing accidents. However, the real-time path needs to consider the motion state of surrounding participants on the road. This work presents a collision avoidance algorithm containing the path-planning and the tracking controller. Firstly, the lateral lane-changing spacing model and the longitudinal braking distance model are presented, describing the vehicle to reactively process dynamic scenarios in real environments. Then, we introduce the safety distance into the artificial potential field algorithm (APF), thereby generating a safe path in a simulated traffic scene. Redesigning the influence range of obstacles based on the collision areas and corresponding safety distance compared with the classic APF. Besides, based on the threat level, the repulsion is divided into the force of the position repulsion and the speed repulsion. The former is related to the relative position and prevents the vehicle from approaching the obstacle. The latter is opposite to the relative speed vector and decelerates the ego vehicle. Simultaneously, the attraction is improved to apply a dynamic environment. Finally, we design a model predictive control (MPC) to track the lateral motion through steering angle and a Fuzzy-PID control to track the longitudinal speed, turning the planned path into an actual trajectory with stable vehicle dynamics. To verify the performance of the proposed method, three cases are simulated to obtain the vehicle responding curves. The simulation results prove that the active collision avoidance algorithm can generate a safe path with comfort and stability.

Percutaneous CT Fluoroscopy-Guided Core Needle Biopsy of Mediastinal Masses: Technical Outcome and Complications of 155 Procedures during a 10-Year Period.

Purpose: To evaluate technical outcome, diagnostic yield and safety of computed tomographic fluoroscopy-guided percutaneous core needle biopsies in patients with mediastinal masses. Methods: Overall, 155 CT fluoroscopy-guided mediastinal core needle biopsies, performed from March 2010 to June 2020 were included. Size of lesion, size of needle, access path, number of success, number of biopsies per session, diagnostic yield, patient’s position, effective dose, rate of complications, tumor localization, size of tumor and histopathological diagnosis were considered. Post-interventional CT was performed, and patients observed for any complications. Complications were classified per the Society of Interventional Radiology (SIR). Results: 148 patients (age, 54.7 ± 18.2) underwent 155 CT-fluoroscopy-guided percutaneous biopsies with tumors in the anterior (114; 73.5%), middle (17; 11%) and posterior (24; 15.5%) mediastinum, of which 152 (98%) were technically successful. For placement of the biopsy needle, in 82 (52.9%) procedures a parasternal trajectory was chosen, in 36 (23.3%) a paravertebral access, in 20 (12.9%) through the lateral intercostal space and in 17 (11%) the thoracic anterior midline, respectively. A total of 136 (89.5%) of the biopsies were considered adequate for a specific histopathologic analysis. Total DLP (dose-length product) was 575.7 ± 488.8 mGy*cm. Mean lesion size was 6.0 ± 3.3 cm. Neoplastic pathology was diagnosed in 115 (75.7%) biopsies and 35 (23%) biopsy samples showed no evidence of malignancy. Minor complications were observed in 18 (11.6%) procedures and major pneumothorax requiring drainage insertion in 3 interventions (1.9%). Conclusion: CT fluoroscopy-guided percutaneous core needle biopsy of mediastinal masses is an effective and safe procedure for the initial assessment of patients with mediastinal tumors.

Significance of the intact of the fascia propria in protection of pelvic plexus during total mesorectal excision

Total mesorectal excision (TME) is the gold standard of surgical treatment for mid and low rectal cancer. It aims to improve the oncological outcomes as well as preserve anal sphincter, sexual and urinary function. Compared with sympathetic nerve injury alone, pelvic plexus and neurovascular bundle (NVB) injury has significant effect on postoperative sexual dysfunction, especially erectile function. Since the lateral surgical plane of TME is narrow and densely packed, dissecting outside the plane causes pelvic plexus injury, while dissecting inside it results in residual mesorectum. In this commentary, we review the research progress of lateral fascial anatomy of TME, and describe the anatomical characteristics of rectosacral fascia based on our previous research results. The prehypogastric fascia acts as a "fascia barrier" when dissecting the lateral space constantly from posterior to anterior. In addition, the pelvic plexus fuses with the prehypogastric fascia which is considered as the outer side layer of rectosacral fascia laterally. Thus, the rectosacral fascia should be dissected at the level of S4 vertebral body posterior to the rectum in an arc shape and then enter the superior-levator space. Before dissecting the lateral spaces, the anterior space of the rectum should be dissected first. After an "U" shape cutting of the Denonvilliers' fascia, the lateral space should be dissected from anterior to posterior. Finally, the lateral attachment of rectosacral fascia is transected to ensure the integrity of the mesorectum without damaging the pelvic plexus.

The utilization of intraoperative contralateral ankle images for syndesmotic reduction

Purpose To evaluate the variability in ankle syndesmotic morphology on contralateral ankle fluoroscopic images and the reductions obtained utilizing these images. Methods A retrospective cohort study was performed at a level one trauma center including 46 adult patients undergoing operative fixation of malleolar ankle fractures that also had anteroposterior (AP) and lateral fluoroscopic images of the uninjured contralateral ankle intraoperatively. Contralateral and post-fixation fluoroscopic images were used to measure the tibiofibular clear space (TFCS) as a proportion of the superior clear space (SCS) on mortise images and the posterior tibiofibular distance (PTFD) as a proportion of the lateral superior clear space (LSCS) on lateral images. Differences between contralateral and post-fixation ankle measurements were compared between those patients with syndesmotic injuries and those without (control group). Results The mean TFCS/SCS and PTFD/LSCS ratios measured on contralateral ankle images were 1.2 (95% confidence interval (CI) 1.1 to 1.3; range 0.7 to 1.8) and 1.8 (95% CI 1.5 to 2; range 0.5 to 3.4). The mean difference between the contralateral and post-fixation TFCS/SCS and PTFD/LSCS in patients with and without syndesmotic fixation was 0.07 vs. 0.13 (F-ratio 0.3, p = 0.5) and -0.2 vs 0.5 (F ratio 5.2, p= 0.02). Conclusions Contralateral syndesmotic measurements varied widely and the utilization of these images allowed for syndesmotic reductions with similar measurements. Intraoperative contralateral ankle images should be considered to assess syndesmotic reduction.

Automatic Discoid Lateral Meniscus Diagnosis from Radiographs Based on Image Processing Tools and Machine Learning.

The aim of the present study is to build a software implementation of a previous study and to diagnose discoid lateral menisci on knee joint radiograph images. A total of 160 images from normal individuals and patients who were diagnosed with discoid lateral menisci were included. Our software implementation includes two parts: preprocessing and measurement. In the first phase, the whole radiograph image was analyzed to obtain basic information about the patient. Machine learning was used to segment the knee joint from the original radiograph image. Image enhancement and denoising tools were used to strengthen the image and remove noise. In the second phase, edge detection was used to quantify important features in the image. A specific algorithm was designed to build a model of the knee joint and measure the parameters. Of the test images, 99.65% were segmented correctly. Furthermore, 97.5% of the tested images were segmented correctly and their parameters were measured successfully. There was no significant difference between manual and automatic measurements in the discoid (P=0.28) and control groups (P=0.15). The mean and standard deviations of the ratio of lateral joint space distance to the height of the lateral tibial spine were compared with the results of manual measurement. The software performed well on raw radiographs, showing a satisfying success rate and robustness. Thus, it is possible to diagnose discoid lateral menisci on radiographs with the help of radiograph-image-analyzing software (BM3D, etc.) and artificial intelligence-related tools (YOLOv3). The results of this study can help build a joint database that contains data from patients and thus can play a role in the diagnosis of discoid lateral menisci and other knee joint diseases in the future.

Quantitative Three-dimensional Assessment of Knee Joint Space Width from Weight-bearing CT.

Background Imaging of structural disease in osteoarthritis has traditionally relied on MRI and radiography. Joint space mapping (JSM) can be used to quantitatively map joint space width (JSW) in three dimensions from CT images. Purpose To demonstrate the reproducibility, repeatability, and feasibility of JSM of the knee using weight-bearing CT images. Materials and Methods Two convenience samples of weight-bearing CT images of left and right knees with radiographic Kellgren-Lawrence grades (KLGs) less than or equal to 2 were acquired from 2014 to 2018 and were analyzed retrospectively with JSM to deliver three-dimensional JSW maps. For reproducibility, images of three sets of knees were used for novice training, and then the JSM output was compared against an expert's assessment. JSM was also performed on 2-week follow-up images in the second cohort, yielding three-dimensional JSW difference maps for repeatability. Statistical parametric mapping was performed on all knee imaging data (KLG, 0-4) to show the feasibility of a surface-based analysis in three dimensions. Results Reproducibility (in 20 individuals; mean age, 58 years ± 7 [standard deviation]; mean body mass index, 28 kg/m2 ± 6; 14 women) and repeatability (in nine individuals; mean age, 53 years ± 6; mean body mass index, 26 kg/m2 ± 4; seven women) reached their lowest performance at a smallest detectable difference less than ±0.1 mm in the central medial tibiofemoral joint space for individuals without radiographically demonstrated disease. The average root mean square coefficient of variation was less than 5% across all groups. Statistical parametric mapping (33 individuals; mean age, 57 years ± 7; mean body mass index, 27 kg/m2 ± 6; 23 women) showed that the central-to-posterior medial joint space was significantly narrower by 0.5 mm for each incremental increase in the KLG (threshold P < .05). One knee (KLG, 2) demonstrated a baseline versus 24-month change in its three-dimensional JSW distribution that was beyond the smallest detectable difference across the lateral joint space. Conclusion Joint space mapping of the knee using weight-bearing CT images is feasible, demonstrating a relationship between the three-dimensional joint space width distribution and structural joint disease. It is reliably learned by novice users, can be personalized for disease phenotypes, and can be used to achieve a smallest detectable difference that is at least 50% smaller than that reported to be achieved at the highest performance level in radiography. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Roemer in this issue.

Lung Ultrasound Surface Wave Elastography for Assessing Patients With Pulmonary Edema.

B-Mode ultrasound insonation of lungs that are dense with extravascular lung water (EVLW) produces characteristic reverberation artifacts termed B-lines. The number of B-lines present demonstrates reasonable correlation to the amount of EVLW. However, analysis of B-line artifacts generated by this modality is semi-quantitative relying on visual interpretation, and as a result, can be subject to inter-observer variability. The purpose of this study was to translate the use of a novel, quantitative lung ultrasound surface wave elastography technique (LUSWE) into the bedside assessment of pulmonary edema in patients admitted with acute congestive heart failure. B-mode lung ultrasound and LUSWE assessment of the lungs were performed using anterior and lateral intercostal spaces in the supine patient. 14 patients were evaluated at admission with reassessment performed 1-2 days after initiation of diuretic therapy. Each exam recorded the total lung B-lines, lung surface wave speeds (at 100, 150, and 200 Hz) and net fluid balance. The patient cohort experienced effective diuresis (average net fluid balance of negative 2.1 liters) with corresponding decrease in pulmonary edema visualized by B-mode ultrasound (average decrease of 13 B-Lines). In addition, LUSWE demonstrated a statistically significant reduction in the magnitude of wave speed from admission to follow-up. The reduction in lung surface wave speed suggests a decrease in lung stiffness (decreased elasticity) mediated by successful reduction of pulmonary edema. In summary, LUSWE is a noninvasive technique for quantifying elastic properties of superficial lung tissue that may prove useful as a diagnostic test, performed at the bedside, for the quantitative assessment of pulmonary edema.

Wave transmission and drag coefficients through dense cylinder arrays: Implications for designing structures for mangrove restoration

Mangrove vegetation constitutes a natural coastal defence against waves and erosion. Despite their protective role, mangrove ecosystems have experienced continuous degradation over the last decades due to human causes. At retreating mangrove coastlines, bamboo structures are built to create new habitat for mangrove colonization. Existing structures have experienced mixed rates of success due to the lack of a scientific basis in their design. Optimizing future structure designs requires investigating the effect of the bamboo poles on waves. We consequently conducted laboratory experiments to measure wave transformation, hydrodynamic forces, and flow velocities inside cylinder arrays, mimicking bamboo poles, with varying cylinder configurations and orientations. The experiments provided relationships for wave transmission, wave reflection, and the drag coefficients for configurations with volumetric porosities between n = 0.64 − 0.9. Configurations with a small lateral spacing (causing higher blockage) and a relatively longer streamwise spacing (causing less sheltering) exhibit larger forces and dissipation per element. Such arrangements enable optimizing wave dissipation at locations where the wave direction has low variability over the year. Placing the poles horizontally instead of vertically increases the forces and wave dissipation per element in relatively deeper water. Based on the experiments, we developed a conceptual analytical model that predicts wave reflection and dissipation through cylinder arrays, including blockage and sheltering. The model can reproduce the influence of cylinder arrangement on wave transformation, and it suggests that accurate predictions of sheltering and wave reflection are important to find optimal designs. Overall, these results provide useful insights on how to model and optimize the design of structures for mangrove restoration.

Three-dimensional morphological changes in the temporomandibular joints of patients with anterior disc displacement with reduction

To investigate the differences in the temporomandibular joints (TMJs) between patients with anterior disc displacement with reduction (ADDwR) and asymptomatic subjects by using 3D morphometric measurements. A total of 15 patients with ADDwR and 10 asymptomatic subjects were enrolled. Then, 3D models of the maxilla and mandible were reconstructed using MIMICS 20.0. Nine morphologic parameters of TMJs on both sides were measured on the 3D solid model. The differences in the parameters were analyzed between the patients and the asymptomatic subjects and between the left and right sides of each group. The horizontal and coronal condylar angles on the ipsilateral side of the patients were significantly greater than those of the asymptomatic subjects (P<0.01). Meanwhile, the sagittal ramus angle (SRA), medial joint space, lateral joint space, superior joint space, anterior joint space, and posterior joint space in the patients were significantly lower than those in the asymptomatic subjects (P<0.01). ADDwR will increase the condylar angles to be significantly greater than the normal level and decrease SRA and articular spaces to be significantly smaller than the normal level. The condyles will be displaced upward, closer to the fossa.

Aerodynamic Interaction Effects Between Propellers in Typical eVTOL Vehicle Configurations

Many electric vertical takeoff and landing concepts are characterized by nontraditional vehicle layouts with distributed propellers. Two propeller interaction types were distinguished in this Paper, which investigates how propeller interaction in side-by-side and one-after-another configuration affects performance, in terms of thrust, power, in-plane forces, and out-of-plane moments, and how those performance effects depend on axial and lateral propeller spacing. A wind-tunnel experiment was performed with two propeller units, one instrumented with a force/torque sensor and the other introducing the aerodynamic interaction. Total pressure and planar particle-image velocimetry measurements were taken to investigate slipstream characteristics. A strong dependency of interaction effects on the geometric layout was found. For side-by-side interaction characteristic of vertical takeoff and transition, interaction effects varied from weak at small angle of attack to strong at larger angles. A drop in rear propeller thrust of up to 30% was found at constant advance ratio. Keeping thrust constant resulted in power penalties up to 13% for the two propellers combined. For one-after-another interaction, characteristic of cruise, a maximum reduction of thrust of up to 80% was observed. Thrust compensation led to power penalties up to 30% for the rear propeller alone. An extended blade element momentum model captured most interaction effects with sufficient accuracy.

Accommodation space as a framework for assessing the response of mangroves to relative sea‐level rise

Mangroves thrive in tidally influenced environments and will be central to any discussion regarding the implications of sea‐level rise for coastal communities. Mangrove forests can respond to sea‐level rise by adjusting their position within a tidal frame that is transitioning upwards, and this response is dependent upon a range of hydrological, sedimentological and ecological factors. The availability of accommodation space, defined as the lateral and vertical space in which mineral and organic sediments and organic material from in situ vegetation can accumulate, is increasingly proposed as a means of conceptualizing the response of shorelines to sea‐level rise. Recent analyses demonstrated the significance accommodation space has on global carbon storage in coastal wetlands over the past few millennia, and likely influence on future carbon sequestration and coastal wetland resilience. Mangrove forest vulnerability is commonly indicated by comparing rates of substrate elevation change to rates of sea‐level rise, but these comparisons may overemphasize mangrove forest vulnerability to sea‐level rise as they do not adequately account for the resilience provided by mineral and organic sediments that previously filled accommodation space and increased substrate elevations beyond critical thresholds for submergence. This paper demonstrates that the geological concept of ‘accommodation space’ applied in a way that incorporates ecological processes and recognizes the full range of processes altering accommodation space may provide a unifying framework for integrating information between disciplines and increasing our understanding of the response of mangrove forests to sea‐level rise. This paper also defines available accommodation space as the space available for sediment accumulation; realized accommodation space as the space that has converted from being available, primarily due to sediment accumulation; and the boundary conditions delimiting both available and realized accommodation space (See Appendix I for the full list of definitions). It is anticipated that this paper will serve as a challenge for researchers across disciplines to collaborate, share and integrate knowledge so that the past is interpreted appropriately and integrated into models, and the best information is available to inform coastal planning and management.

Study some of hydraulic parameters of border drip irrigation system and effect of some soil conditioners on soil properties and growth of Wheat )Triticum aestivum L.(.

"A field experiment was conducted in Maysan in the winter season 2017-2018 on silt clay soil to determine the hydraulic standards for border drip irrigation system depending on the lateral pipes Spacing and measurement site within network in effect of soil conditioners and level water irrigation on the saline distribution horizontal and vertical distribution .the experimental treatment of three lateral pipes Spacing at 30 cm (S1) , 45 cm (S2) and 60 cm (S3) whit three soil conditioners organic material, used oil and control , the conditioners were added based on the dry weight of the soil , and two levels of irrigation water 75% and 100% from Ep . The treatments were applicated using RCBD , results showed that the decrease in the soil salt content due to the decrease in the distance between the field pipes , treatment S1 recorded the highest values (3.72 and 3.21) dsm-1 and it was significantly different from the two treatments S2 (4.04 and 3.55) dSM-1 and S3 (4.40 and 3). 88) dsm-1 , soil conditioners treatment of Oil was superior to the lowest values (3.33 and 2.82) dsm-1 , followed by the OM treatment (3.94 and 3.29) dsm-1 , with a significant difference compared to the comparison values (4.89 and4.53) dsm-1 , as well the results showed that the treatment of irrigation level exceeded 100% (3.92 and 3.32) dsm-1 with significant differences compared with the irrigation level of 75% (4.19 and 3.77) dsm-1 at the beginning and end of the growing season respectively. There was also a decrease in the saline content, both horizontally and vertically due to the decrease in the distance between the field pipes, the use of irrigation level 100%, and with the addition of conditioners.."

Molecular structure characterization of bituminous coal in Northern China via XRD, Raman and FTIR spectroscopy

Bituminous coal is used widely for a variety of applications despite causing a range of problems within processes. The complexity and heterogeneity of the molecular structure of coal is one of the reasons for problems during use. Investigation into the molecular structure of the bituminous coal is reported from using X-ray diffraction (XRD), Raman spectroscopy, and Fourier Transform infrared (FTIR) spectroscopy experiments on four coal samples from coal mines in Northern China. The average lateral sizes (La), stacking heights (Lc) and interlayer spacing (d002) of the coal samples’ crystallite structures derived from the XRD ranged from 25.78 to 27.93 Å, 17.27 to 25.88 Å and 3.40 to 3.52 Å, respectively; and the G-D1, ID1/IG and La of the samples ranged from 245.06 to 249.63 cm−1, 2.18 to 2.48 and 18.16 to 20.64 Å, respectively. The FTIR spectra reveals that coal samples incorporate oxygen-containing functional groups, aliphatic functional groups, aromatic functional groups and hydroxyl functional groups. Results show these four coal samples contained a low degree of ordered microcrystalline units with a low degree of aromatic conformation. The samples have the largest proportion of oxygenated functional groups, followed by aromatic structures, aliphatic structures and hydroxyl groups. Results from this study could inform the ongoing study of molecular structural characteristics of bituminous coal as well as help our understanding of properties such as wettability and pore structure.

Research on rolling process of bow parts with variable lateral roll spacing based on optimal bending angle distribution function

For roll-bending formation in bow-shaped sheet metal parts, the distance of the traditional roll-forming transverse unit is constant, which often causes corner wrinkles, corner cracks, tearing, springback, and peak longitudinal strain defects throughout the formation process. To solve these shortcomings, this paper proposes an optimized bending angle distribution function to synergize the variable lateral roll distance technique. By parameterizing the abstract function according to the function boundary trajectory, the bending angle of each roll pass is measured; furthermore, the optimal function curve can be obtained through finite element analysis. Then, the roll-bending simulation is conducted, and the forming angle of the sheet metal parts is redistributed to determine the most effective reduction of peak longitudinal strain and transverse roll spacing. The bending angle distribution function aids the variable transverse roll distance technology to execute roll-bending experiments on 3004Al arch parts, ultimately obtaining the optimal roll-bending angle and transverse roll distance. The results of the roll forming simulation, based on the optimized bending angle distribution function and variable transverse roll distance technology, corroborate the experimental results, and good roll forming efficiency and quality are achieved.

Collective locomotion of two-dimensional lattices of flapping plates. Part 1. Numerical method, single-plate case and lattice input power

Abstract

Stress Urinary Incontinence: Treatment With Platelet-Rich-Plasma Injection and Placement of Polydioxanone Threads—A Pilot Study

Stress urinary incontinence is an important clinical problem that affects millions of women worldwide. The aim of this article was the evaluation of a minimally invasive procedure as an alternative treatment for mild urinary stress incontinence in women, using platelet-rich-plasma (PRP) injections and polydioxanone (PDO) threads. A total of 23 patients with mild urinary incontinence, mean age 46, were evaluated with detailed history, examination, urinary diary, complete laboratory tests, ultrasonography, urodynamic studies, and completion of International Consultation on Incontinence Questionaire–Urinary Incontinence Short Form (ICIQ-UI SF). Under local anesthesia, PRP was injected through the anterior vaginal wall, PDO threads placed in paraurethral, suburethral, and lateral urethrovaginal spaces, using instruments developed for safe and effective performance. Patients were analyzed at 1, 2, 4, 8 weeks and 6 months posttreatment. A total of 10 patients were biopsed preoperatively and 60 days after treatment. Symptoms and ICIQ-UI SF score were significantly improved. Postoperative urodynamic studies were normal in all cases. Biopsies after treatment showed a dense connective tissue tridimensional mesh. No complications or adverse effects were observed. All patients declared satisfaction with results, will have the procedure again, and will recommend it. The minimally invasive technique presented here results in strengthening of the paraurethral, suburethral, and lateral urethrovaginal spaces and the mucosa of the anterior vaginal wall. The combination of PRP injections and the placement of PDO threads creates a fibrotic and absorbable mesh-like structure, aimed to increase the urethral resistance, so that under effort the intravesical pressure does not overcome the urethral pressure. These results suggest that the procedure is safe and a cost-effective alternative in patients with mild urinary incontinence, reducing the need for invasive surgical procedures. Larger studies are needed to confirm the results of this study.