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In machine vision systems, the objectives to be detected, such as circuit boards, may be composed of many different materials and shapes, which can lead to highlights, shadows and error information in captured images under traditional uniform illumination. A lighting system that generates tailored irradiance in different regions in machine vision is needed. This paper proposes a design method for an LED lens and obtains special total-internal-reflection (TIR) lenses that generate tailored illumination, which can adapt to the reflectance and shape of a target. Differential-algebraic equations (DAEs) based on the conservation of flux are established to ensure the uniform illumination on the targets, nonlinear equations based on the edge-ray principle are employed to generate the spots with tailored shapes and the numerical solutions can be fitted into the proposed lenses. Six different tailored faculae are generated to verify the proposed method. The results show that the uniformity of tailored facula can exceed 87%, and the light efficiency can exceed 85%. In particular, the contrast of the irradiance among different regions can be adjusted by the boundary conditions; thus, the proposed method can satisfy the complex demand for machine vision and be applied to improve vision detection systems in production lines.

Purpose Olecranon fracture is a common upper limb fracture, and several surgical approaches have been advocated for its fixation. To overcome the complications associated with common techniques, we present a novel shape-memory alloy concentrator, an alternative for tension band compression, to fix olecranon fracture. Methods Fifty-seven patients (26 men and 31 women) with olecranon fracture, with a mean age of 45 years, were included in this study. Each patient had undergone open reduction and internal fixation using the Nitinol (Ni-Ti) arched shape-memory connector (ASC). The clinical assessments were performed using the Disability of the Arm, Shoulder, and Hand (DASH) questionnaire and the Mayo Elbow Performance (MEP) score, which were both recorded at the final follow-up visit. Results The patients were followed up for 44 months on average (range, 31 to 56 months). No patients were lost to follow-up, and all of the olecranon fractures healed in an average of 15 weeks (range, 10 to 34 weeks). The mean DASH score was 8.6 (range, 0 to 32.4), and the mean MEP score was 92.5 (range, 74 to 100). Nine patients showed postoperative complications: prominent hardware (2), infection (1), loss of the range of functional motion (5), and heterotopic ossification (1). Conclusion The ASC may serve as a favorable device for multi-fragmented and comminuted fractures with rare hardware irritation and may also provide continuous concentrative compression to accelerate osseous healing, thereby aiding the restoration and permitting an early rehabilitation with a low incidence of postoperative complications.

As an important branch of computational optics, the light field can simultaneously record the spatial intensity and propagation direction of light, which provides a new way to realize three-dimensional (3D) measurement. Although light field measuring system (LFMS) can quickly detect nontransparent surfaces, specular light affects the overall measurement result. In this paper, an LFMS based on a diffuse light source and polarization technology is proposed to eliminate specular light and obtain a more accurate 3D reconstruction result in one exposure. During the measurement, a series of images corresponding to continuously varying polarization angle are captured, in which the value(V)-channel value distribution is used as the criterion of specular light removal efficiency, and hence, the image at the optimal polarization angle is obtained, in which the influence of specular light is removed. The depth map and specular light removal efficiency are experimentally compared with those of the traditional LFMS. The experimental results show that the depth map error can be greatly reduced, which further verifies the feasibility of the proposed method and system. The present study can be extended to the traditional optical system or other machine vision measurement methods involving specular light.

Background. The past decade has witnessed the development of ultrasound in orthopaedics, the growth rate of publications has been accelerating. In this study, analysis of the publications on ultrasound in orthopaedics over the past decade has been completed. We aim to provide inspiration for future research on ultrasound in orthopaedics through our work.Methods. All relevant publications between 2009 and 2020 from Web of Science were collected. Statistical Package for Social Science and GraphPad Prism 8 software were used to generate and analyse diagrams. Meanwhile, from the aspects of co-occurring keywords, VOSviewer software and CiteSpace were employed to visualize the research trends.Results. 1,677 publications with a citation frequency of 20,311 were identified. The United States published most publications in this filed and the number of citations was also the highest, as well as the highest H-index. Although China ranked sixth in terms of the number of publications, the growth trend in the future will be fastest. Furthermore, Skeletal Radiology published the most papers related to ultrasound in orthopaedics, Ozcakar, L had published the most papers, and a study by Kwon, YM received the highest citation frequency. The keywords about "MRI", "complication", "female" and "male" were noted as new topics.Conclusions. Through the research, while the contributions of the publications from the United States were significant, the growth rate of Chinese publications in the future cannot be ignored. Moreover, it is hypothesized that diagnosis and epidemiology studies may become hotspots.

Background Heat stroke (HS) is an acute physical disorder that is associated with a high risk of organ dysfunction and even death. HS patients are usually treated symptomatically and conservatively; however, there remains a lack of specific and effective drugs in clinical practice. An analysis of publication contributions from institutions, journals and authors in different countries/regions was used to study research progress and trends regarding HS. Methods We extracted all relevant publications on HS between 1989 and 2019 from Web of Science. Using the Statistical Package for Social Science (SPSS, version 24) and the software GraphPad Prism 8, graphs were generated and statistical analyses were performed, while VOSviewer software was employed to visualize the research trends in HS from the perspectives of co-occurring keywords. Results As of April 14, 2020, we identified 1443 publications with a citation frequency of 5216. The United States accounted for the largest number of publications (36.2%) and the highest number of citations (14,410), as well as the highest H-index at 74. Although the sum of publications from China ranked second, there was a contradiction between the quantity and quality of publications. Furthermore, Medicine & Science in Sports & Exercise published the most papers related to HS, with Lin MT publishing the most papers in this field (112), while the review by Knochel JP received the highest citation frequency at 969. The keyword heat-stress appeared most recently, with an average appearing year of 2015.5. In the clinical research cluster, exertional heat-stroke was determined to be the hotspot, while ambient-temperature and heat waves were the new trends in the epidemiological research cluster. Conclusions Corresponding to this important field, while the contributions of the publications from the United States were significant, the mismatch between the quantity and quality of publications from China must be examined. Moreover, it is hypothesized that clinical and epidemiological studies may become hotspots in the near future.

Background: To explore the role of nickel-titanium(NiTi) shape memory alloy embracing fixator in determination of implantation angle of hip tumor prosthesis stem and analyze its efficacy. Methods: 36 patients with proximal femur tumor were treated with extended tumor resection and prosthetic replacement. 14 patients received prosthetic replacements with the embracing fixators fixing between the junction of the prosthesis stem and the femur temporarily, while the other 22 patients received the same replacements but without the fixators. Following aspects were compared: occurrence of complications, limb function and active hip ROM.Results: There are fewer cases of hip dislocation in the group received prosthetic replacements with the use of embracing fixators. Occurrence of deep infection presented no difference between the two groups. Better limb function and higher active range of motion (ROM) on abduction or flexion were also found in the group using embracing fixators. Conclusion: Ni-Ti shape memory alloy embracing fixator plays a key part in assisting the accurate implantation angle of the prosthesis stem in the prosthetic replacement. The prosthesis stem can be adjusted to the optimal angle with the help of the embracing fixator. Patients have lower chance of dislocation, better limb function, and higher active hip ROM. Trial registration: retrospectively registered.

A light field microscope can realize three-dimensional measurement through only one exposure by the addition of a critical optical component called a microlens array (MLA). MLA errors will introduce aberrations in the captured image and then affect measurement results. This paper proposes a light field measuring system with aberration correction based on imaging analysis. The effect of MLA errors is investigated and quantitatively analyzed through a series of simulation studies. Aberration correction is realized based on computational imaging, in which an image segmentation and fusion distortion model is employed to correct the distortion, while a gradient-based linear recognition algorithm is used to address MLA rotation errors. Experimental results show that the developed light field measuring system can achieve improved measurement accuracy by correcting aberrations with the proposed algorithms.

This study aims to compare the clinical outcomes of the nickel–titanium arched shape–memory alloy connector (hereafter referred to as the ASC) and tension band fixation for the treatment of transverse patellar fractures. We retrospectively analyzed a total of 257 patients with transverse patellar fractures who were treated at our emergency orthopaedics department from March 2010 to March 2017. Either an ASC or the Kirschner wire (K-wire) tension band had been used to treat these fractures according to surgeons' experience and preference. We compared operative details, postoperative recovery, and postoperative knee function at 6 months. In terms of surgical duration, blood loss, incision length, length of hospital stay, and postoperative complications, patients in the ASC group showed significantly better results than patients in the K-wire group (p 0.05). Though, there were similar functional outcomes between two groups whose transverse patellar fractures were different methods, we found that the ASC method was a more reliable, more minimally invasive, and safer treatment option than the tension band wiring method using K-wires, resulting in less tissue damage, shorter surgical duration, shorter length of hospital stay, and fewer complications.

Accurate puncture of the renal collecting system is crucial to the success of percutaneous nephrolithotomy and presents a technical challenge for urologists. Here, we introduced the Surgical Approach Visualization and Navigation (SAVN) system, a novel navigation system to assist puncture and reduce intraoperative radiation. Twenty kidneys of 10 cadavers were randomly divided into two groups for renal calyx puncture. In the control group, traditional fluoroscopy was used for guidance, while SAVN system was used in the experimental group. Puncture duration, number of puncture attempts, total number of intraoperative fluoroscopies, and number of fluoroscopies during the puncture procedure were recorded. The puncture duration was 14.2 ± 2.5 s in SAVN group and 48.3 ± 7.1 s in conventional group (P

Trauma with foreign objects retained within the human body has become a common surgical emergency condition. Traditional surgical methods often involve creating large incisions in soft tissue and may lead to additional complications during wound healing. We have developed a new method of removing foreign bodies from patients’ abdomens by using laparoscopy with the help of a novel navigation system that provides accurate positioning. This approach is minimally invasive and simple. This is the first combination of both technologies in this field.

Light field imaging technology can obtain three-dimensional (3D) information of a test surface in a single exposure. Traditional light field reconstruction algorithms not only take a long time to trace back to the original image, but also require the exact parameters of the light field system, such as the position and posture of a microlens array (MLA), which will cause errors in the reconstructed image if these parameters cannot be precisely obtained. This paper proposes a reconstruction algorithm for light field imaging based on the point spread function (PSF), which does not require prior knowledge of the system. The accurate PSF derivation process of a light field system is presented, and modeling and simulation were conducted to obtain the relationship between the spatial distribution characteristics and the PSF of the light field system. A morphology-based method is proposed to analyze the overlapping area of the subimages of light field images to identify the accurate spatial location of the MLA used in the system, which is thereafter used to accurately refocus light field imaging. A light field system is built to verify the algorithm’s effectiveness. Experimental results show that the measurement accuracy is increased over 41.0% compared with the traditional method by measuring a step standard. The accuracy of parameters is also improved through a microstructure measurement with a peak-to-valley value of 25.4% and root mean square value of 23.5% improvement. This further validates that the algorithm can effectively improve the refocusing efficiency and the accuracy of the light field imaging results with the superiority of refocusing light field imaging without prior knowledge of the system. The proposed method provides a new solution for fast and accurate 3D measurement based on a light field.

This investigation was intended to elucidate lncRNA-miRNA networks that could explain inflammation underlying sepsis progression.In the first place, four kinds of mice models were established, namely, SHAM group (n = 30), trauma (TH) group (n = 30), lipopolysaccharide (LPS) group (n = 30) and TH + LPS group (n = 30). Their lung, spleen and liver tissues were gathered for determination of TNF-α, IL-6, IL-10 and MCP-1 levels. Furthermore, mouse mononuclear macrophage leukemia cell line (RAW264.7) was stimulated by LPS to establish inflammation cell models. Then si-NEAT1s, pcDNA3.1-NEAT1, miR-495-3p mimic, miR-495-3p inhibitor, miR-NC, miR-211 mimic and miR-211 inhibitor were, respectively, transfected into the cells, so as to observe the impacts of NEAT1, miR-495-3p and miR-211 on cytokine levels released by the cells.The survival condition of mice in the TH + LPS group was undesirable, in relative to mice in the LPS group and SHAM group (both P 0.05). High-level NEAT1 and low-level miR-495-3p/miR-211 were associated with poor survival of mice in the TH+LPS group (P 0.05). Additionally, the correlation between NEAT1/miR-495-3p/miR-211 level and cytokine level was the strongest among TH+LPS-treated mice, in comparison to mice treated by TH or LPS. Furthermore, up-regulation of NEAT1 level and down-regulation of miR-495-3p/miR-211 level could aggravate inflammation in LPS-treated RAW264.7 cells. The miR-495-3p and miR-211 herein, were both subjected to sponging of NEAT1, possibly affected inflammation responses in RAW264.7 cells, respectively, through modulating STAT3 and PI3K/AKT signaling.LncRNA NEAT1 exhibited great potential sepsis diagnosis and treatment, considering its modifying miR-495-3p/STAT3 axis and miR-211/PI3K/AKT axis in inflammation cell models.

Precision measurement of three-dimensional (3D) microstructures has drawn great interests from researchers and industries. Currently there are a bunch of high precision measurement methods such as contour-graphs, interferometers and optical computed tomography used in industrial applications. Nonetheless, the loss of information, low efficiency and possible surface damaging of traditional ways still exist. This paper presents a new way to measure micro/nano structures based on light field microscope. The light field information of the microstructures is acquired by using a microlens array which is inserted between the camera sensor and the objective lens. Then a series of regular sub-images are recorded by the photosensor, which is used to reconstruct a 3D image by the developed algorithms. The non-contact shooting process is realized through only one exposure which is much more efficient than the traditional ways. Microlens array with aspheric surface is also designed and used in the developed system, to eliminate aberrations and compensate the loss of spatial resolution. A series of simulation and experimental studies have been undertaken to measure microstructures, and the feasibility of the developed system is validated.

Background Lateral malleolus fractures occur frequently. The common techniques for fixing purely lateral malleolus fractures are often challenging, owing to the extent of soft tissue damage and fracture non-union. Herein, we report a new treatment that entails minimally invasive insertion and continuous compression of the broken ends as a novel technique, and evaluate its clinical results. Methods This study enrolled 21 patients (13 males and 8 females; mean age 32.06±3.45 years, range 23-69 years) with purely lateral malleolus fractures. Each patient underwent open reduction treatment with a mini locking plate for internal fixation and compression of the fracture end with an Arched Shape-Memory Connector (ASC). The clinical assessments were made using the American Orthopedic Foot and Ankle Society (AOFAS) scores, which were recorded at the final follow-up visit. Results The patients were followed for an average of 14.7±1.2 months (range, 12-18 months). None of the patients showed surgical failure, and all of the purely lateral malleolus fractures healed in an average of 12.6±1.5 weeks (range, 10-16 weeks). The mean AOFAS score was 88.94 (range, 83-90). Conclusions The new treatment had beneficial outcomes for purely lateral malleolus fractures. Mini locking plates are minimally invasive for surgical intervention, and combined with continuous concentrated compression with an ASC to accelerate osseous healing, they aid in restoration of function and enable early rehabilitation with a low incidence of postoperative complications.

Purpose To summarize the techniques and clinical effectiveness in treating scaphoid nonunion with nickel–titanium (Ni–Ti) arched shape-memory alloy connector in combination with autologous iliac bone grafts. Methods This study retrospectively analyzed 18 scaphoid nonunion cases treated with arched connectors with autologous iliac bone grafts. Based on scaphoid nonunion, 2 cases were classified as type II (fibrous union), 4 cases as type III (mild sclerotic union), 6 cases as type IV (moderate resorption and sclerosis), 5 cases as type V (severe bone resorption and sclerosis), and 1 case as type VI (pseudarthrosis formation). At the first 4, 8 and 12 weeks after the surgery, wrist anteroposterior, lateral X-ray were obtained, respectively, to evaluate bone healing. Patients who had not yet reached the standard of healing at 12 weeks after surgery would continue to receive additional appointments for follow-up visits, such as 14 weeks, 16 weeks, 18 weeks after surgery, until their imaging studies had achieved satisfactory bone healing. Clinical effectiveness was evaluated comprehensively, based on bone union time, Mayo wrist score, and visual analog pain score. Results All 18 patients achieved satisfactory reduction and fixation with a mean union time of 4.2 months. Preoperative Mayo wrist score averaged 57.4 and average final postoperative follow-up was 91.4. On the other hand, mean preoperative VAS score was 6.8, and final postoperative follow-up average was 1.6. Mayo wrist score of the overall treatment effectiveness was excellent (90–100) in 12 cases, good (80–90) in 5 cases, and acceptable (60–80) in 1 case with zero poor (below 60) cases observed. Statistical analysis suggested that a statistically significant improvement in fracture healing, wrist function recovery and visual analog pain after surgery when compared to the scores of the patients before surgery. Conclusion Using Ni–Ti arched shape-memory alloy connector in combination with autologous bone grafting provided a new modality to treat scaphoid nonunions in a less traumatic, convenient to operate and satisfactory manner in treatment outcomes, and thus is worthy of further application.

Stress ulcers are a common complication in critically ill patients, but the underlying mechanism is little known. This study characterized the function of the p50 subunit of NF-κB in an experimental model of cold immobilization stress-induced gastric ulcers. Stress-induced gastric mucosal inflammation and gastric injury were examined in wild-type and NF-κB p50-deficient mice. When subjected to cold immobilization stress, NF-κB was rapidly activated in the gastric mucosa in WT mice whereas the majority of κB DNA-binding activity was abrogated from p50−/− mice. Deficiency of p50 ameliorated stress-induced expression of TNF-α, MIP-2, and ICAM-1, resulting in reduced mucosal accumulation of neutrophils and gastric injury. These data indicated a critical role for the p50 in the gastric mucosal inflammatory response to cold restraint stress.

Freeform has been widely applied in both imaging optics and non-imaging optics. Optical freeform surfaces can be fabricated by ultra-precision machining process. The geometrical errors of these freeform optics can be measured by contact or non-contact approaches. Imaging quality is one of the major criteria for imaging optics, while illumination distribution and energy efficiency are the important performance parameters for non-imaging optics. It is necessary and helpful to relate the geometrical errors and the optical performance of the freeform optics, so as to provide a well balance between the machining accuracy and efficiency. This paper surveys the current research on the relationship between optical performance and geometrical errors of optical surfaces, including the research work for the measurement of geometrical errors of freeform surfaces, and the valuation of optical performance. It shows that there is still a lack of research work undertaken to quantitatively analyze the relationship between the optical performance and geometrical errors. Therefore, it is interesting to carry out some future work on the quantitative analysis of the relationship between specific optical parameters and certain frequency surface errors.

Operative treatment is usually recommended in displaced patella fractures. Several techniques have been advocated for internal fixation of patella fractures. Despite the relatively good clinical outcomes that have been demonstrated in many studies, postoperative morbidities such as fixation failure, nonunion, infection, and knee stiffness are not uncommon. We present a new alternative treatment technique for displaced patellar fractures. Between April 1995 and May 2005, we used the Nitinol Patella Concentrator (NTPC) to treat 156 consecutive patients with displaced patellar fractures. Injuries arose from vehicular accidents in 56 (35.9%) cases, direct falls onto the knee in 85 (54.5%) cases, and sports injuries in 15 (9.6%) cases. The mean patient age was 46.3 years (range, 25-77 years). Clinical assessments were made using the Bostman knee score and the MOS SF-36 questionnaire (Medical Outcomes Study 36-item short-form health survey), which were both recorded at the final follow-up visit. The mean follow-up was 7.3 years (range, 6-17 years). At the final follow-up, the Bostman knee scores were excellent in 88 cases (28-30), good in 55 (20-27), and unsatisfactory in 13 (

To investigate the effects of the HDMX polymorphism on sarcoma risk. Relevant studies were identified by searching the PubMed, Embase, and Web of Science databases. Data were extracted by two independent investigators. Odds ratios (ORs) and 95 % confidence intervals (CIs) were calculated using a fixed-effects model to assess the association between the HDMX polymorphism and sarcoma risk. We also conducted heterogeneity test, sensitivity analysis, and publication bias test. A meta-analysis of four published case-control studies involving 1,115 subjects (379 cases and 736 controls) showed no statistical association between the HDMX polymorphism and sarcoma risk (ORTT vs. GG 0.88, 95 % CI 0.68-1.14, P heterogeneity 0.819; ORTT + TG vs. GG 0.95, 95 % CI 0.79-1.15, P heterogeneity 0.937; ORTT vs. TG + GG 0.82, 95 % CI 0.65-1.04, P heterogeneity 0.589; ORT allele vs. G allele 0.91, 95 % CI 0.79-1.05, P heterogeneity 0.727; ORTG vs. GG 0.95, 95 % CI 0.74-1.22, P heterogeneity = 0.869). This null result did not alter when data were stratified according to ethnicity. Our meta-analysis indicates that the HDMX polymorphism is unlikely to contribute to individual susceptibility to sarcoma.

Sepsis is a common and critical complication in surgical patients that often leads to multiple organ failure syndrome (MOFS), including acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). Despite intensive supportive care and treatment modalities, the mortality of these patients remains high. In this study, we investigated the role of Burton's tyrosine kinase (BTK), a member of the Btk/Tec family of cytoplasmic tyrosine kinases, in the pathogenesis of sepsis, and evaluated the protective effect of in vivo Btk RNA interference in a mouse model of cecal ligation and puncture (CLP)-induced sepsis. After intratracheal injection of Btk siRNA, the mice were then subjected to CLP to induce sepsis. The results demonstrated that this approach conferred potent protection against sepsis-induced ALI, as evidenced by a significant reduction in pathological scores, epithelial cell apoptosis, pulmonary edema, vascular permeability, and the expression of inflammatory cytokines and neutrophil infiltration in the lung tissues of septic mice. In addition, RNA interference of Btk significantly suppressed p-38 and iNOS signaling pathways in transduced alveolar macrophages in vitro. These results identify a novel role for BTK in lethal sepsis and provide a potential new therapeutic approach to sepsis and ALI.

Gluteal muscle contracture is a clinical syndrome that involves contracture and distortion of the gluteal muscles and fascia fibers due to multiple causes. Physical examination demonstrates a characteristic gait due to hip adduction and internal thigh rotation. This study introduces a new minimally invasive method for surgical release of gluteal muscle contracture. Patients with gluteal muscle contracture were assigned to 4 categories: type A, contracture occurred mainly in the iliotibial tract; type B, contracture occurred in the Iliotibial tract and gluteus maximus; type C1, movement of the contraction band was palpable and a snapping sound was audible during squatting; and type C2, movement of the contraction band was not palpable or almost absent and a snapping sound was audible during squatting. This classification method allowed prediction of the anatomic location of these pathological contractures and determination of the type of surgery required. Four critical points were used to define the operative field and served as points to mark a surgical incision smaller than 4 mm. The contracture was easily released in this carefully marked operative field without causing significant neurovascular damage. Over a period of 5 years, between March 2003 and June 2008, the authors treated 1059 patients with this method and achieved excellent outcomes. Most patients were fully active within 12 weeks, with the assistance of an early postoperative rehabilitation program. The most significant complication was a postoperative periarticular hematoma, which occurred in 3 patients within 10 days postoperatively and required surgical ligation of the bleeding vessel.