Local Block Research Articles

The effects of different anesthetic approaches on recurrence in the surgical treatment of ganglion cysts

Aim: The surgical treatment of ganglion cysts usually involves local anesthesia (LA), regional anesthesia (RA), and axillary block applications. We aimed to show the effects of these anesthesia types on recurrence in surgically treated ganglion cysts. Material and Method: Between 2017-2019,142 patients were operated on in our clinic due to the dorsal ganglion cyst of the wrist. Cysts outside the dorsal region and patients who did not regularly attend their follow-up visits for at least 12 months were excluded. One hundred and thirty-five patients, with a mean age of 39.3 (15-73) years, were included in the study. LA (Group I) was applied to the patients who stated that they could tolerate the pain, and RA was used on those who stated that they could not (Group II) after preoperative anesthesia consultations. The files of the patients in both groups were reviewed retrospectively, and the effect of anesthesia type on recurrence was investigated. Results: Recurrence rates were significantly lower in the RA group compared to those in the LA group (p=0.049). The risk of recurrence in the LA group was 2.80 (0.95-8.28) times higher than in the RA group. The mean operation time of the RA group was significantly lower than that of the local anesthesia group (p=0.0001). Conclusion: The fact that RA allows tourniquet applications with deeper and longer-lasting anesthesia compared to LA increases surgical comfort and makes way for the comfortable dissection of the cyst and total excision of all components within a short operative time.

Scientific progress in information theory quantifiers

The Bandt and Pompe method (BPM) has been successfully applied to estimate the information theory quantifiers. The most significant limitation of the BPM is that this approach is based on point estimation. This research provides scientific progress into the several applications of the information theory quantifiers. In this way, we propose a new statistic confidence interval estimation method for the Permutation Entropy, Fisher Information Measure, and Macroeconophysics Indicator of Efficiency (MIEE). Therefore, we examine quarterly Gross Domestic Product (GDP) time series for 25 countries members of the Organization for Economic Co-operation and Development (OECD). The periods cover more than 59 years, from Q1-1960 to Q3-2019, with 238 data points. For each GDP time series, we employ the non-parametric method Local Block Bootstrap to provide a stylized fact about an empirical distribution for these data taking into account the information theory quantifiers. Based on the values of the empirical distribution of the information theory quantifiers, we construct the Shannon-Fisher causality plane (SFCP), which allows us to quantify the disorder and evaluate randomness present in the time series of quarterly GDP in each country. In addition, we use information theory quantifiers to rank the most efficient countries in allocating the resources arising from economic growth to generate a virtuous cycle of growth. Also, we apply the Principal Component Analysis (PCA) to check the results of the empirical distribution of the MIEE. We find the PCA promotes the same result as the MIEE. Our results suggest an alternative form of clustering using information theory quantifiers linked to the similarity of countries’ GDPs and the mutual influences of one country’s economic growth on the others.

Tramadol Administered Intravenously Either as a Bolus or a Slow Injection in Pain Management of Romifidine-Sedated Calves Undergoing Umbilical Hernia Repair

Umbilical hernias in calves occur with relative frequency. Most abdominal surgeries can be performed in cattle using standing sedation and local blocks. Romifidine is widely used in calves, alone or in combination with opioids. Tramadol administered as an intravenous slow injection provided better analgesia than an IV bolus in cows. The aim of the present study was to compare the response to surgical stimulus, and sedative effects of tramadol administered intravenously either as a bolus or a slow injection in romifidinesedated calves. Twenty Frisian calves undergoing umbilical hernia repair received romifidine (0.08 mg/kg IM; time 0) followed by tramadol (1 mg/kg IV) 5 min later either as a bolus (n = 10, B group) or a slow injection over 10 min (n = 10, SI group). Surgical area was infiltrated with lidocaine (4 mg/kg). Heart rate (HR), respiratory rate (RR), systolic, dyastolic and mean arterial pressure (SAP, DAP, MAP), sedation scores and response to surgical stimulus were recorded for up to 55 min. After the calves recovered a standing position, postoperative pain scores were assessed for up to 50 min. Sedation scores were significantly higher in the SI group than in the B group at 55 min (p < 0.05). HR, RR, SAP and response to surgical stimulus were significantly higher in the B group than in the SI group (p < 0.05). No significant differences were recorded in postoperative pain scores between groups (p > 0.05). Romifidine IM followed by intravenous tramadol, as a bolus or slow injection and local infiltration with lidocaine provided adequate sedation and analgesia in calves undergoing umbilical hernia repair.

Super-Resolution Reconstruction of Remote Sensing Images Based on Symmetric Local Fusion Blocks

In view of the rich information and strong autocorrelation of remote sensing images, a super-resolution reconstruction algorithm based on symmetric local fusion blocks is proposed using a convolutional neural network based on local fusion blocks, which improves the effect of high-frequency information reconstruction. By setting local fusion in the residual block, the problem of insufficient high-frequency feature extraction is alleviated, and the reconstruction accuracy of remote sensing images of deep networks is improved. To improve the utilization of global features and reduce the computational complexity of the network, a residual method is used to set the symmetric jump connection between the local fusion blocks to form the symmetry between them. Experimental results show that the reconstruction results of 2-, 3-, and 4-fold sampling factors on the UC Merced and nwpu-resisc45 remote sensing datasets are better than those of comparison algorithms in image clarity and edge sharpness, and the reconstruction results are better in objective evaluation and subjective vision.

Mechanistic insights into spontaneous transition from cellular alternans to ventricular fibrillation.

T-wave alternans (TWA) has been used for predicting the risk of malignant cardiac arrhythmias and sudden cardiac death (SCD) in multiple clinical settings; however, possible mechanism(s) underlying the spontaneous transition from cellular alternans reflected by TWA to arrhythmias in impaired repolarization remains unclear. The healthy guinea pig ventricular myocytes under E-4031 blocking IKr (0.1μM, N=12; 0.3μM, N=10; 1μM, N=10) were evaluated using whole-cell patch-clamp. The electrophysiological properties of isolated perfused guinea pig hearts under E-4031 (0.1μM, N=5; 0.3μM, N=5; 1μM, N=5) were evaluated using dual- optical mapping. The amplitude/threshold/restitution curves of action potential duration (APD) alternans and potential mechanism(s) underlying the spontaneous transition of cellular alternans to ventricular fibrillation (VF) were examined. There were longer APD80 and increased amplitude and threshold of APD alternans in E-4031 group compared with baseline group, which was reflected by more pronounced arrhythmogenesis at the tissue level, and were associated with steep restitution curves of the APD and the conduction velocity (CV). Conduction of AP alternans augmented tissue's functional spatiotemporal heterogeneity of regional AP/Ca alternans, as well as the AP/Ca dispersion, leading to localized uni-directional conduction block that spontaneous facilitated the formation of reentrant excitation waves without the need for additional premature stimulus. Our results provide a possible mechanism for the spontaneous transition from cardiac electrical alternans in cellular action potentials and intercellular conduction without the involvement of premature excitations, and explain the increased susceptibility to ventricular arrhythmias in impaired repolarization. In this study, we implemented voltage-clamp and dual-optical mapping approaches to investigate the underlying mechanism(s) for the arrhythmogenesis of cardiac alternans in the guinea pig heart at cellular and tissue levels. Our results demonstrated a spontaneous development of reentry from cellular alternans, arising from a combined actions of restitution properties of action potential duration, conduction velocity of excitation wave and interplay between alternants of action potential and the intracellular Ca handling. We believe this study provides new insights into underlying the mechanism, by which cellular cardiac alternans spontaneously evolves into cardiac arrhythmias.

A descriptive study of day care stapled hemorrhoidopexy surgery in grade-4 hemorrhoids under pudendal block

Background: Hemorrhoids are one of the most common afflictions of human beings from times immemorial. It is said that 40% of population have symptoms due to hemorrhoids at some time in their lives. Stapled hemorrhoidopexy under local anesthesia has been emerging as the procedure of choice for symptomatic hemorrhoids. Aims and Objectives: The objectives of the study are as follows: (1) To assess the advantage of performing stapled hemorrhoidopexy under local pudendal block. (2) To study the post-operative complications after stapled hemorrhoidopexy. (3) To assess the feasibility of stapled hemorrhoidopexy in grade IV hemorrhoids. (4) To assess the advantages of stapled hemorrhoidopexy in anal skin regression after surgery. Materials and Methods: 50 patients of grade 4 hemorrhoids were operated by hemorrhoid stapler under local anesthesia. Results: Stapled hemorrhoidopexy under local anesthesia can be safely performed as a day care procedure in grade IV hemorrhoids. Patients following stapled hemorrhoidopexy under local anesthesia have reduced post-operative pain, hospital stay, analgesic requirements, and earlier return to work, early mobility out of bed, less operative time, short learning curve, less operative complications, cost effectiveness, and good patient satisfaction. Conclusion: Stapled hemorrhoidopexy under local anesthesia is feasible to be used in those patients who are unwilling and unfit for other modes of anesthesia with better results with lesser complication rate and as a day care procedure.

Image Super-Resolution Reconstruction Based on Residual Convolution and Double Attention Mechanism

Currently, single-image super-resolution reconstruction based on deep learning has achieved good results. To address the problems that most networks will have long training time, weak image learning ability and not fully utilizing the high frequency information of images, an image super-resolution reconstruction method based on residual convolution and double attention mechanism is proposed. The model performs deep feature extraction of the image by cascading deep convolutional networks, introduces local residual blocks to solve the model degradation brought by too many network parameters, and embeds the dual attention mechanism module in the residual blocks for adaptive calibration to adjust the feature map weights of each channel and the spatial correlation between features, so as to obtain deep texture detail information and reconstruct the feature image by sub-pixel convolutional layers to up sampling to reconstruct the high-resolution image. In the test sets of Set5 and Set14, peak signal-to-noise ratio (PSNR) and structural similarity (SSIM) are used as evaluation indexes, while comparing SRCNN, FSRCNN and VDSR methods all reconstructed images with better results. The experimental results show that the method can effectively improve the utilization of high-frequency feature information and can increase the reconstruction capability of the images to a certain extent.

Update on the anatomy of the brachial plexus in dogs: Body weight correlation and contralateral comparison in a cadaveric study.

A thorough knowledge of the anatomy of the brachial plexus is pivotal for diagnostic, therapeutic and anaesthetic purposes in order to correctly locate the nerve and reduce the incidence of complications when performing surgery or a local anaesthetic block of the brachial plexus. In this study, the anatomy of the brachial plexus in dogs was reviewed; the depth and diameter of each nerve were evaluated, and the contralateral limbs were compared. Eighteen canine cadavers were included and were divided into: small (SB); medium (MB) and large (LB) breed dogs. After dissection, the spinal roots and the suprascapular, subscapular, axillary, radial, ulnar, median, and musculocutaneous nerves were identified. The following evaluations were recorded: the origin of the nerves from the spinal roots, the roots and the nerve diameters, and the distance of the nerves root from the skin at the level of the scapula-humeral joint and from the interscapular region. A total of thirty-six brachial plexuses were evaluated; all originated from the ventral rami of the C6 to T1 spinal nerves. In the LB dogs, the root and the nerve diameters were larger as compared with the other two groups. In this group, also the mean distance of T1 from the skin at the level of the scapula-humeral joint and the average distance of the nerve roots from the skin of the interscapular region were also greater as compared with the other groups. No significant differences were recorded between the contralateral limbs. In the dogs in the present study, the origin of the nerves of the brachial plexus were similar to those previously reported; however, the presence of minor individual variations was confirmed between the right and the left limbs within the same dog between the right and the left limb. This is the first time that the diameters and the depth of the nerves have been described and positively correlated with body weight.

Study on prevention and control mechanism of runoff water hazard in thick coal seam mining in valley terrain

During the mining of thick coal seams under the gully slope, the mining-induced fractures are prone to connect with the gully runoff, which may induce potential water hazards and affect underground production. Based on the occurrence characteristics of coal seams and the landform in the gully-developed mining area, the coal seam mining under the slope of Na’er Coal Mine and Baoshan Coal Mine was taken as the engineering background, the seasonal runoff of gullies was considered as the influencing factors of the safe mining, and the spatial relationship between the working face and the gully slope was analyzed when the mining-induced fractures were connected with the gully surface and caused the gully runoff water disaster. The research results show that the occurrence structure of the gully slope has a greater impact on the strata movement of the slope. When the key layer is incomplete, the horizontal sliding and local block overturning of the slope rock strata are strong; when the key layer is complete, the horizontal sliding and local block overturning of the slope rock strata are weakened. According to the safety distance of the working face and the generalized model of safety coal pillar setting, the method of setting the safety coal pillar was used to prevent the connection of slipping cracks of the rock strata at the slope bottom and the gully surface during the slope mining, thus preventing the occurrence of runoff hazards during the thick coal seams mining in the valley terrain. The results can provide a theoretical basis and technical support for the prevention and control of seasonal runoff hazards, as well as a reference for the prevention and control of mining-induced landslides, water conservation mining, and ecological environment protection.

Toward Visual Behavior and Attention Understanding for Augmented 360 Degree Videos

Augmented reality (AR) overlays digital content onto reality. In an AR system, correct and precise estimations of user visual fixations and head movements can enhance the quality of experience by allocating more computational resources for analyzing, rendering, and 3D registration on the areas of interest. However, there is inadequate research to help in understanding the visual explorations of the users when using an AR system or modeling AR visual attention. To bridge the gap between the saliency prediction on real-world scenes and on scenes augmented by virtual information, we construct the ARVR saliency dataset. The virtual reality (VR) technique is employed to simulate the real-world. Annotations of object recognition and tracking as augmented contents are blended into omnidirectional videos. The saliency annotations of head and eye movements for both original and augmented videos are collected and together constitute the ARVR dataset. We also design a model that is capable of solving the saliency prediction problem in AR. Local block images are extracted to simulate the viewport and offset the projection distortion. Conspicuous visual cues in the local block images are extracted to constitute the spatial features. The optical flow information is estimated as an important temporal feature. We also consider the interplay between virtual information and reality. The composition of the augmentation information is distinguished, and the joint effects of adversarial augmentation and complementary augmentation are estimated. The Markov chain is constructed with block images as graph nodes. In the determination of the edge weights, both the characteristics of the viewing behaviors and the visual saliency mechanisms are considered. The order of importance for block images is estimated through the state of equilibrium of the Markov chain. Extensive experiments are conducted to demonstrate the effectiveness of the proposed method.

The enhanced recovery after surgery (ERAS) protocol in elderly patients with acute cholecystitis: A retrospective study.

Enhanced recovery after surgery (ERAS) protocol is a perioperative management theory aimed at reducing the injury of surgical patients and accelerating postoperative recovery. It has been widely recognized and applied in elective surgery. This study aimed to evaluate the clinical value of the ERAS protocol during the perioperative period of laparoscopic cholecystectomy in elderly patients with acute cholecystitis. This study aimed to evaluate the clinical value of the ERAS protocol during the perioperative period of laparoscopic cholecystectomy in elderly patients with acute cholecystitis. We collected medical data from 126 elderly patients with acute cholecystitis from October 2018 to August 2021. Among the 126 patients, 70 were included in the ERAS group and 56 in the traditional group. We analyzed the clinical data and postoperative indicators of the 2 groups. No significant differences were observed regarding the general characteristics of the 2 groups (P > .05). The ERAS group had significantly earlier time to first flatus, time to first ambulation, and time to solid intake, compared with the traditional group (P < .001); additionally, the ERAS group had significantly shorter stay and gentler feeling of postoperative pain (P < .001). Furthermore, the ERAS group had significant incidences of lower postoperative lung (P = .029) and abdominal cavity infection (P = .025) compared to the traditional group. No significant difference was observed regarding the incidences of other postoperative complications between the 2 groups (P > .05). The ERAS protocol helps reduce elderly patients' stress reactions and accelerate postoperative recovery. Thus, it is effective and beneficial to implement the ERAS protocol during the perioperative period of elderly patients with acute cholecystitis.

A Comparative Study between Surgical Techniques by Local Excisional debridement with a Xylocaine Block and Excisional Debridement under General Anesthesia, in Necrotizing Fasciitis

Objective: This study aimed to compare the clinical and economic outcomes between excisional debridement with a local xylocaine block (LAD) and excisional debridement under general anesthesia (GAD). Material and Methods: This retrospective medical record review was designed to review records of excisional debridement in necrotizing fasciitis (NF) at Sisaket Hospital from January 1, 2017, to December 31, 2019. Outcome measures were clinical outcomes at the preoperative time (baseline data, door-to-operating room), peri-operative time (operating time, blood loss, number of reoperations), postoperative time (mortality rate, length of stay, pain score, opioid drug use), types of NF, and direct costs of treatment by the provider’s perspective. Descriptive statistics, chi-square and Mann-Whitney U test were used. Results: The results of 245 patients showed that LAD was superior to GAD in terms of door-to-operating room time, lower operating time and blood loss, shorter length of hospital stay and lower cost of treatment. Moreover, the LAD showed a lower postoperative pain score, and less opioid drug use when compared to GAD. There were no significant differences in mortality rate, sites of infection and types of NF. Conclusion: LAD showed better clinical outcomes and lower cost of treatment when compared to GAD in the treatment of NF. Nevertheless, excisional debridement under a LAD could be a choice for small wounds at the lower extremities in hospitals with limited resources, and insufficient numbers of anesthesiologists.

Efficacy of transversalis fascia plane block as a novel ındication for varicocelectomy surgery: prospective randomized controlled study

BackgroundVaricocele occurs as a result of dilatation of the pampiniform plexus in the spermatic veins. In this study, our primary aim was to evaluate the effect of Transversalis Fascia Plane Block (TFPB) on pain scores in the postoperative period in patients undergoing varicocelectomy surgery, and our secondary aim was to evaluate the effect of TFPB on analgesic consumption.MethodsThe study was initiated following local ethics committee approval, and sixty ASA I-II patients > 18y scheduled to undergo varicocelectomy and who consented to participation were enrolled. Before the procedure, the patients were randomly assigned two groups: Transversalis Fascia Plan block group (Group TFPB) or surgical incision site infiltration group (Group I).All surgeries were carried out under general anesthesia, and microsurgery using the subinguinal approach. After surgical suturing, TFPB and local infiltration blocks were applied prior to termination of anesthesia.For each block, 20 mL of 0.25% bupivacaine was utilized. Patients' demographic information, passive and active VAS ratings after surgery, usage of non steroidal anti-inflammatory medications and rescue analgesia, and the requirement for rescue analgesia, were recorded.ResultsA total of 60 patients were included in the study. In terms of demographic data, there was no difference between the groups. At all hours, there was a statistically significant decrease in favor of Group TFPB in terms of active and passive VAS scores (p < 0.001), non steroidal anti-inflammatory analgesic use (p < 0.05), and tramadol requirement (p < 0.001).ConclusionThis study has shown that TFPB can provide a more effective analgesia when compared to surgical site infiltration.

Infrared Small Target Detection via Center-Surround Gray Difference Measure With Local Image Block Analysis

Exristing algorithms may suffer from high false alarm rate and low detection probability when detecting dim small target under intricate background clutters and heavy noise. To address this problem, a target detection method based on local image block analysis and center-surround gray difference measure (CGDM) is proposed in this article. First, the infrared image is decomposed into a group of local blocks. The gray information of each block are sorted in ascending order and the last element is deleted, then the maximum gray jump point (MGJP) is extracted by using differential operation. Second, a protection zone is formed with MGJP as the center, and the maximal intensity of protection zone (MIPZ) is extracted. Next, by comparing the gray intensity of MGJP and MIPZ values, the potential target blocks can be reliably selected, while most background blocks and noise blocks will be discarded. After that, the CGDM is presented to enhance the target and suppress background clutters, and then, the center-surround local contrast measure (CLCM) is designed to further suppress the high-intensity clutter residues by searching the target center and revising the protection zone. Finally, the weighted center-surround gray difference measure (WCGDM) is defined by CLCM WCGDM map to recognize real targets. Extensive experiments show that the proposed method outperforms several existing algorithms in small target detection under complex background clutters, and it is robust to various target shapes, target sizes, and noise types.

Motif-GCNs With Local and Non-Local Temporal Blocks for Skeleton-Based Action Recognition.

Recent works have achieved remarkable performance for action recognition with human skeletal data by utilizing graph convolutional models. Existing models mainly focus on developing graph convolutional operations to encode structural properties of a skeletal graph, whose topology is manually predefined and fixed over all action samples. Some recent works further take sample-dependent relationships among joints into consideration. However, the complex relationships between arbitrary pairwise joints are difficult to learn and the temporal features between frames are not fully exploited by simply using traditional convolutions with small local kernels. In this paper, we propose a motif-based graph convolution method, which makes use of sample-dependent latent relations among non-physically connected joints to impose a high-order locality and assigns different semantic roles to physical neighbors of a joint to encode hierarchical structures. Furthermore, we propose a sparsity-promoting loss function to learn a sparse motif adjacency matrix for latent dependencies in non-physical connections. For extracting effective temporal information, we propose an efficient local temporal block. It adopts partial dense connections to reuse temporal features in local time windows, and enrich a variety of information flow by gradient combination. In addition, we introduce a non-local temporal block to capture global dependencies among frames. Our model can capture local and non-local relationships both spatially and temporally, by integrating the local and non-local temporal blocks into the sparse motif-based graph convolutional networks (SMotif-GCNs). Comprehensive experiments on four large-scale datasets show that our model outperforms the state-of-the-art methods. Our code is publicly available at https://github.com/wenyh1616/SAMotif-GCN.

HIP ULTRASOUND-GUIDED HAEMATOMA (HUSH) BLOCK FOR INTRACAPSULAR NECK OF FEMUR FRACTURES OUTPERFORMS FASCIA-ILIACA BLOCK

Regional anaesthesia is integral to best practice analgesia for patients with neck of femur fractures (NOFFs). These patients are generally frail and are vulnerable to side effects of opioid analgesia. Femoral nerve block (FNB) or fascia-iliaca block (FIB) can reduce opioid requirement. Literature supports good efficacy for extra-capsular NOFFs however it is acknowledged to be suboptimal for intracapsular fractures.We present a novel technique, using point of care ultrasound guidance to perform hip ultrasound guided haematoma (HUSH) aspiration, and injection of local anaesthetic (block) for intracapsular NOFFs.This a case control series. A consecutive series of cognitively intact patients, with an isolated intra-capsular NOFF, received a HUSH block using 10mls of 0.75% Ropivicaine. Haematoma was aspirated and volume recorded. This was performed in addition to standard NOFF pathway analgesia that includes a FIB and multimodal analgesia including opioids. Visual Analogue Scale (VAS)pain scores at rest and on movement were recorded pre and post procedure as well as combined morphine equivalent units administered post HUSH block. The control arm was a retrospective group of similar patients who followed the routine care pathway including a FIB. VAS pain scores from observation charts and usage of morphine equivalent units were calculated.Ten patients consented to receive HUSH blocks and we included thirty-eight patients in our control series. The HUSH block group showed mean VAS pain score of 4.2/10 at rest and 8.6 on movement prior to block. In the time after the block, VAS pain scores reduced to 1.5 at rest (p=0.007) and 3.1 on movement (p=0.0001) with a mean total morphine equivalent use of 8.75mg. This is significantly different from the control group's mean VAS pain at rest score 6.9 (p=0.0001) and 24.1mg total morphine equivalent (p=0.07).HUSH Block in addition to fascia iliaca block appears to significantly better pain relief in intracapsular neck of femur fracture patients when compared to fascia iliaca block alone. We believe it is relatively easy to perform with readily available ultrasound scanners in emergency departments.

Induction of Local and Systemic Blocking Antibodies by PQ Grass 27600 SU for the Treatment of Seasonal Allergic Rhinitis: A RDBPC Pilot Study

PQ Grass, a grass pollen allergoid using MicroCrystalline Tyrosine and Monophosphoryl Lipid A as an adjuvant system, is a well-tolerated subcutaneous immunotherapy for seasonal allergic rhinitis. We hypothesised that PQ Grass 27600 SU is effective in inducing functional allergen-specific blocking antibodies.

Evaluation of a constant rate intravenous infusion of dexmedetomidine on the duration of a femoral and sciatic nerve block using lidocaine in dogs.

This study investigated the effects of 1 μg/kg/h intravenous constant rate infusion (CRI) of dexmedetomidine on the sensory and motor blockade for femoral and sciatic nerve blocks in dogs undergoing stifle surgery. Client-owned dogs referred for stifle surgery were enrolled in this prospective, randomized, blinded study. Dogs were pre-medicated with acepromazine (0.005-0.01 mg/kg intramuscularly, IM); anesthesia was induced with propofol intravenously and maintained with isoflurane in a mixture of air and oxygen. Electrolocation-guided sciatic and femoral nerve blocks with lidocaine 2% (0.15 mL/kg) were performed using the parasacral and lateral pre-iliac approaches, respectively. After performing local block, a systemic infusion of saline solution (group C) or dexmedetomidine (group D) was started at a CRI at 1 ml/kg/h and continued until the end of surgery. Dexmedetomidine was infused at a dose of 1 μg/kg/h. Respiratory and hemodynamic variables were recorded during surgery. Sensory and motor blockade was evaluated by response to pinching the skin innervated by the sciatic/femoral nerves, with forceps and by observing the dogs' ability to walk and testing proprioception at 30, 60, 120, 180, and 240 min after extubation. Analgesia was monitored with SF-GCPS. Methadone IM was administered as rescue analgesia. Intraoperative data were analyzed by analysis of variance, while postoperative data were analyzed by the independent two-tailed t-test and a Kaplan-Meier test (p < 0.05). Twenty dogs were included in this study (10/group). A significant difference in the recovery of sensory nerve function was observed between the groups. The mean durations of the sensory blockade for femoral and sciatic nerves, respectively, was longer (p < 0.001) for group D [168 (146-191, 95% CI), 161 (143-179, 95% CI) min] than in group C [120 (96.1-144, 95% CI), 116 (90.9-142, 95% CI]. No differences in the recovery of patellar and tibial reflexes, proprioceptive function, and ability to walk were found among groups. The overall postoperative rescue analgesia requirement was significantly different (p = 0.019) between groups, with an incidence of 5/10 (50%) dogs in group D and 10/10 (100%) dogs in group C. Dexmedetomidine administered as a CRI (1 μg/kg/h) combined with local lidocaine increases the duration of the sensory component of the sciatic and femoral nerve blocks and reduces the requirement for additional analgesia during the immediate postoperative hours.

Two-scale solution for tripped turbulent boundary layer

Recent findings on the Reynolds-number-dependent behaviour of near-wall turbulence in terms of the ‘foot-printing’ of outer large-scale structures call for a new modelling development. A two-scale framework was proposed to couple a local fine-mesh solution with a global coarse-mesh solution by He (Intl J. Numer. Meth. Fluids, vol. 86, 2018, pp. 655–677). The methodology was implemented and demonstrated by Chen &amp; He (J. Fluid Mech, vol. 933, 2022, p. A47) for a canonical turbulent channel flow, where the mesh-count scaling with Reynolds number is potentially reduced from $O(R{e^2})$ for a conventional wall-resolved large-eddy simulation (WRLES) to $O(R{e^1})$ . The present work extends the two-scale method to turbulent boundary layers. A two-dimensional roughness element is used to trip a turbulent boundary layer. It is observed that large-scale disturbances originating at the trip have a much shorter lifetime and weaker foot-printing signatures on near-wall flow compared to those long streaky coherent structures in well-developed wall-bounded turbulent flows. Modal analyses show that the impact of trip-induced large scales can be adequately captured by a locally embedded fine-mesh block. For the tripped turbulent boundary layer, a Chebyshev block-spectral mapping is adopted to propagate source terms from the local fine-mesh blocks to the global coarse-mesh domain, driving to a target solution for the upscaled equations. The computed mean statistics and energy spectra are in good agreement with corresponding experimental data, WRLES and direct numerical simulation (DNS) results. The overall mesh count– $Re$ scaling is estimated to reduce from $O(R{e^{1.8}})$ for the full wall-resolved LES to $O(R{e^{0.9}})$ for the present two-scale solution.

MCAFNet: A Multiscale Channel Attention Fusion Network for Semantic Segmentation of Remote Sensing Images

Semantic segmentation for urban remote sensing images is one of the most-crucial tasks in the field of remote sensing. Remote sensing images contain rich information on ground objects, such as shape, location, and boundary and can be found in high-resolution remote sensing images. It is exceedingly challenging to identify remote sensing images because of the large intraclass variance and low interclass variance caused by these objects. In this article, we propose a multiscale hierarchical channel attention fusion network model based on a transformer and CNN, which we name the multiscale channel attention fusion network (MCAFNet). MCAFNet uses ResNet-50 and Vit-B/16 to learn the global–local context, and this strengthens the semantic feature representation. Specifically, a global–local transformer block (GLTB) is deployed in the encoder stage. This design handles image details at low resolution and extracts global image features better than previous methods. In the decoder module, a channel attention optimization module and a fusion module are added to better integrate high- and low-dimensional feature maps, which enhances the network’s ability to obtain small-scale semantic information. The proposed method is conducted on the ISPRS Vaihingen and Potsdam datasets. Both quantitative and qualitative evaluations show the competitive performance of MCAFNet in comparison to the performance of the mainstream methods. In addition, we performed extensive ablation experiments on the Vaihingen dataset in order to test the effectiveness of multiple network components.