Between-session chasing of losses and wins in an online eCasino.

Background and aims: This study characterized chasing behaviour as the time to return to an online gambling website after a losing or a winning visit. Methods: We analyzed a naturalistic dataset from an eCasino (PlayNow.com, the provincial platform for British Columbia, Canada), comprising 1,909,681 sessions from 15,544 individuals. Analyses distinguished sessions on slot machines, blackjack, roulette, video poker, probability games, or mixed-category sessions. Results: Overall, gamblers on most games returned more slowly as a function of the prior loss, and more quickly as a function of the prior win. Loss chasing intensities in blackjack, probability, video poker, and mixed sessions did not differ significantly from slot machines, but roulette was associated with shorter intervals to return (b = -0.13, p < 0.001). Similarly, win chasing did not vary across slot machines, blackjack, probability games, and video poker, but roulette (b = -0.08, p < 0.001) and mixed (b = -0.02, p = 0.009) sessions were associated with shorter intervals. Discussion and conclusions: The average behavioural patterns provide limited evidence for loss chasing but clearly indicate win chasing. Although slot machines are commonly considered a high-risk product, roulette in our analyses was associated with the greatest chasing intensities.

Regenerative therapies for femoral head necrosis in the past two decades: a systematic review and network meta-analysis.

BACKGROUND: Regenerative techniques combined with core decompression (CD) are commonly used to treat osteonecrosis of the femoral head (ONFH). However, no consensus exists on regeneration therapy combined with CD that performs optimally. Therefore, we evaluated six regenerative therapies combined with CD treatment using a Bayesian network meta-analysis (NMA). METHODS: We searched PubMed, Embase, Cochrane Library, and Web of Science databases. Six common regeneration techniques were categorized into the following groups with CD as the control group: (1) autologous bone graft (ABG), (2) autologous bone graft combined with bone marrow aspirate concentrate (ABG + BMAC), (3) bone marrow aspirate concentrate (BMAC), (4) free vascular autologous bone graft (FVBG), (5) expanded mesenchymal stem cells (MSCs), and (6) platelet-rich plasma (PRP). The conversion rate to total hip arthroplasty (THA) and progression rate to femoral head necrosis were compared among the six treatments. RESULT: A total of 17 literature were included in this study. In the NMA, two of the six treatment strategies demonstrated higher response in preventing the progression of ONFH than CD: MSCs (odds ratio [OR]: 0.098, 95% confidence interval [CI]: 0.0087-0.87) and BMAC (OR: 0.27, 95% CI: 0.073-0.73). Additionally, two of the six treatment strategies were effective techniques in preventing the conversion of ONFH to THA: MSCs (OR: 0.062, 95% CI: 0.0038-0.40) and BMAC (OR: 0.32, 95% CI: 0.1-0.074). No significant difference was found among FVBG, PRP, ABG + BMAC, ABG, and CD in preventing ONFH progression and conversion to THA (P > 0.05). CONCLUSIONS: Our NMA found that MSCs and BMAC were effective in preventing ONFH progression and conversion to THA among the six regenerative therapies. According to the surface under the cumulative ranking value, MSCs ranked first, followed by BMAC. Additionally, based on our NMA results, MSCs and BMAC following CD may be necessary to prevent ONFH progression and conversion to THA. Therefore, these findings provide evidence for the use of regenerative therapy for ONFH.

Comparative analysis of surgical interventions for osteonecrosis of the femoral head: a network meta-analysis of randomized controlled trials.

BACKGROUND: Despite several surgical options, there remains no consensus regarding the optimal approach for osteonecrosis of the femoral head (ONFH), a prevalent and refractory disease. To determine the most suitable treatment modality, we compared randomized controlled trials (RCTs) that evaluated multiple surgical treatments for ONFH using a Bayesian network meta-analysis (NMA). METHODS: The outcomes of 11 different surgical treatments were assessed using NMA comparisons of the rate of progression of femoral head necrosis, the rate of conversion to total hip arthroplasty, and improvement of the Harris hip score (HHS). A random effects model was used to analyze the odds ratio (OR) or mean difference, and risk of bias was assessed using the Cochrane risk of bias assessment tool for randomized trials. The confidence of the results was assessed using the confidence in network meta-analysis tool. RESULTS: A total of 18 RCTs were included in the meta-analysis. Compared with core decompression (CD), the forest plot showed that autologous bone grafting (ABG), free fibula grafting (FFG), vascularized bone grafting (VBG), autologous bone grafting combined with bone marrow aspirate concentrate (ABG + BMAC), and biomaterial grafting combined with vascularized bone grafting (BMG + VBG) delayed ONFH progression. Among them, ABG + BMAC showed the most promising results (OR 0.019; 95% confidence interval [CI] 0.0012-0.25). However, upon comparing CD with different surgical modalities, no significant differences were found in preventing total hip arthroplasty. Furthermore, we cannot draw conclusions regarding the HHS due to attribution and high heterogeneity across the studies. CONCLUSION: Overall, ABG, VBG, FFG, ABG + BMAC, and BMG + VBG showed significant results in preventing ONFH progression compared with that shown by CD. Based on the surface under the cumulative ranking, ABG + BMAC was the most effective. Moreover, all treatments involving bone grafting were found to be effective, possibly indicating the necessity of its use in the treatment of ONFH.

Analysis of the characteristics of valveless piezoelectric pump with crescent dune bluff body.

To improve the output flow characteristics of the piezoelectric pump in one direction, a new valveless piezoelectric pump with a crescent dune bluff body has been proposed. The pump can achieve low damage to the active substance on the premise that the active cell can guarantee the transport volume. By comparing with the hemispherically deficient and imitated meniscus resistance fluid, the barchan dune resistance fluid which can effectively improve the unidirectional output of the piezoelectric pump is obtained. Combined with the pump theoretical flow calculation formula, these influencing parameters, the degree of inclination, the sand ridge radius and the order of the crescent dune were analyzed. Finally, an experimental prototype of a valveless piezoelectric pump has been fabricated by 3D printing technology, and the pump flow test is being conducted. The relationship between frequency, voltage and output flow has been obtained. The test results show that with a dune inclination of 37.5, a sand ridge radius of 6.75 mm and a dune order of 4, the flow rate of the piezoelectric pump is best at 194.7 mL/min. The experimental results agree with the simulation results, showing the effectiveness of the valveless piezoelectric pump structure.

A Dual-Functional Perovskite-Based Photodetector and Memristor for Visual Memory.

The imitation of human visual memory demands the multifunctional integration of light sensors similar to the eyes, and image memory, similar to the brain. Although humans have already implemented electronic devices with visual memory functions, these devices require a combination of various components and logical circuits. However, the combination of visual perception and high-performance information storage capabilities into a single device to achieve visual memory remains challenging. In this study, inspired by the function of human visual memory, a dual-functional perovskite-based photodetector (PD) and memristor are designed to realize visual perception and memory capacities. As a PD, it realizes an ultrahigh self-powered responsivity of 276 mA W-1 , a high detectivity of 4.7 × 1011  Jones (530 nm; light intensities, 2.34 mW cm-2 ), and a high rectification ratio of ≈100 (±2 V). As a memristor, an ultrahigh on/off ratio (≈105 ), an ultralow power consumption of 3 × 10-11  W, a low setting voltage (0.15 V), and a long retention time (>7000 s) are realized. Moreover, the dual-functional device has the capacity to perceive and remember light paths and store data with good cyclic stability. This device exhibits perceptual and cyclic erasable memory functions, which provides new opportunities for mimicking human visual memory in future multifunctional applications.

Sclerotic zone in femoral head necrosis: from pathophysiology to therapeutic implications.

This review summarizes the sclerotic zone's pathophysiology, characterization, formation process, and impact on femoral head necrosis. The sclerotic zone is a reaction interface formed during the repair of femoral head necrosis. Compared with normal bone tissue, the mechanical properties of the sclerotic zone are significantly enhanced. Many factors influence the formation of the sclerotic zone, including mechanics, bone metabolism, angiogenesis, and other biological processes. The sclerotic zone plays an essential role in preventing the collapse of the femoral head and can predict the risk of the collapse of the femoral head. Regulating the formation of the sclerotic zone of the femoral head has become a direction worthy of study in treating femoral head necrosis.

Comparing a modified simple-conditional with the conditional-only methods in teaching Chinese children with autism.

Instruction in auditory-visual conditional discriminations for young children with autism spectrum disorder is typically based on either a conditional-only or a simple-conditional method. In this study, we evaluated a modified simple-conditional method in which we removed the steps for which visual comparisons were presented in isolation. We compared this modified simple-conditional method with the conditional-only method when teaching auditory-visual conditional discriminations to six young Chinese children with autism spectrum disorder. We included two efficiency measures: total sessions and time to mastery. Our results replicated the findings of previous research in that both methods were efficacious for all but one participant. Although efficacy outcomes were similar across methods, the conditional-only method was more efficient across participants according to sessions and time to mastery. Thus, the results add to support for the use of the conditional-only method to teach auditory-visual conditional discriminations.

Photoimaging with Color-Sensing Abilities by Tuning the Band Gap of a Single-Crystal Lead-Free Perovskite.

Photodetectors (PDs) composed of lead-free metal halide perovskites have been a shining topic in optoelectronics. However, it is debatable whether perovskites are an n-type or p-type semiconductor with a direct or indirect band gap. Furthermore, to date, little research has been conducted on lead-free metal halide perovskites with color-sensing abilities. Herein, for the first time, single-crystal MA3Bi2I3xBr9-3x (x = 0, 1, 2, and 3) perovskites were systematically studied, and the results showed that MA3Bi2I9 is a p-type direct-band-gap semiconductor, whereas MA3Bi2Br9 is an n-type indirect-band-gap semiconductor. Furthermore, the band gap of MA3Bi2I3xBr9-3x (x = 0, 1, 2, and 3) perovskites can be systematically tuned from 2.06 to 2.55 eV, affording it with color-sensing abilities from 450 to 580 nm, respectively. The representative Au-MA3Bi2I9-ITO (ITO = indium tin oxide) PD exhibits a superior self-powered photodetecting performance with a high responsivity (15.8 mA W-1; 580 nm, 1.0 mW cm-2), detectivity (8.1 × 1011 Jones), an on/off ratio (4231), LDR (72.5 dB) and a fast response speed (rise time of 2 µs and decay time of 29 µs). This study not only facilitates the theoretical understanding of the band gap of perovskite materials but also sheds light on the application of lead-free perovskites in object interaction and color perception.

Bone grafting for femoral head necrosis in the past decade: a systematic review and network meta-analysis.

BACKGROUND: Bone grafting is considered a method that can provide mechanical and structural support to the femoral head and prevent the collapse of the femoral head after core decompression (CD). However, there are no consensus guidelines on which bone grafting method is best after CD. The authors assessed the efficacy of various bone grafting modalities and CD through a Bayesian network meta-analysis (NMA). MATERIALS AND METHODS: Ten articles were retrieved from PubMed, ScienceDirect, and Cochrane Library searches. Bone graft modalities are categorized into four, and CD is the control group: (1) CD, (2) autologous bone graft (ABG), (3) biomaterial bone graft (BBG), (4) bone graft combined with bone marrow graft (BG+BM), and (5) free vascular bone graft (FVBG). The rates of conversion to total hip arthroplasty (THA), femoral head necrosis progression rate, and Harris hip score (HHS) improvement were compared among the five treatments. RESULTS: A total of 816 hips were included in the NMA: specifically, 118 hips in CD, 334 in ABG, 133 in BBG, 113 in BG+BM, and 118 in FVBG. The NMA results show no significant differences in preventing conversion to THA and improving HHS in each group. All bone graft methods are better than CD in preventing osteonecrosis of the femoral head (ONFH) progress [ABG: odds ratio (OR)=0.21, 95% CI: 0.07-0.56; BBG: OR=0.13, 95% CI: 0.03-0.52; BG+BM: OR=0.06, 95% CI: 0.01-0.24; FVBG: OR=0.11, 95% CI: 0.02-0.38]. The rankgrams indicate that BG+BM is the best intervention in preventing conversion to THA (73%), preventing ONFH progress (75%), and improving HHS (57%), followed by the BBG in preventing conversion to THA (54%), improving HHS (38%), and the FVBG in preventing ONFH progress (42%). CONCLUSIONS: This finding indicates that bone grafting after CD is necessary to prevent ONFH progression. Moreover, bone grafts combined with bone marrow grafts and BBG seem to be effective treatment methods in ONFH.

Denoising method of machine tool vibration signal based on variational mode decomposition and Whale-Tabu optimization algorithm.

The noise from other sources is inevitably mixed in the vibration information of CNC machine tools obtained using the sensors. In this work, a de-noising method based on joint analysis is proposed. The variational mode decomposition (VMD), correlation analysis (CA), and wavelet threshold (WT) denoising are used to denoise the original signal. First, VMD decomposes noisy signals into multiple intrinsic mode functions (IMFs). The penalty factor and decomposition level of VMD parameters are selected by the optimization algorithm by combining the whale optimization algorithm (WOA) and tabu search (TS). The minimum permutation entropy of IMF is used as the fitness function of the proposed fusion algorithm. Then, the IMF is divided into three categories by using the cross-correlation number. They include the pure components, signals containing noise, and complete noise components. Then, the WT method is used to further denoise the signals, and signal reconstruction is performed with the pure component to obtain the denoised signal. This joint analysis denoising method is named TS-WOA-VMD-CA-WT. The simulation results show that the fusion optimization algorithm proposed in this work has better performance as compared to the single optimization algorithm. It performs effectively when applied to the actual machine tool vibration signal denoising. Therefore, the proposed TS-WOA-VMD-CA-WT method is superior to other existing denoising techniques and has good generality, which is expected to be popularized and applied more widely.

The effects of nano-hydroxyapatite/polyamide 66 scaffold on dog femoral head osteonecrosis model: a preclinical study.

The lack of mechanical support in the bone tunnel formed after CD often results in a poor therapeutic effect in ONFH. The n-HA/P66 has excellent biocompatibility and mechanical properties and has been widely used in bone regeneration. The present study aimed to evaluate the effects of n-HA/P66 scaffold treatment in a dog model of ONFH. A FEA was performed to analyze the mechanical changes in the femoral head after CD and n-HA/P66 scaffold or tantalum rod implantation. Fifteen male beagles were selected to establish the model of ONFH by liquid nitrogen freezing method, and the models were identified by x-ray and MRI 4 weeks after modeling and randomly divided into three groups. Nine weeks later, femoral head samples were taken for morphology, micro-CT, and histological examination. The FEA showed that the n-HA/P66 scaffold proved the structural support in the bone tunnel, similar to the tantalum rod. The morphology showed that the femoral head with n-HA/P66 implantation is intact, while the femoral heads in the model group and CD group are collapsing. Moreover, the micro-CT results of the n-HA/P66 scaffold group were better than the model group and the CD group, and the interface between the n-HA/P66 scaffold and bone tissue is blurred. Furthermore, the histological result also verifies the alterations in micro-CT, and bone tissue grows in the bone tunnel with n-HA/P66 scaffold implanted while few in the CD group. The CD results in a lack of mechanical support in the femoral head subchondral bone and bone tunnel high stress. The n-HA/P66 scaffold implantation can provide mechanical support and relieve high stress induced by CD. The n-HA/P66 scaffold can treat femoral head necrosis and provide the bone tissue growth scaffold for the femoral head after CD to promote bone tissue regeneration.

A four parallel laser-based simultaneous measurement method for 6-degrees-of-freedom errors of rigid body with translational motion.

The measurement of six-degrees-of-freedom (6-DOF) errors of rigid bodies can show the real and accurate spatial pose of those rigid bodies. It plays a major role in precision calibration, spacecraft docking, machining, assembly, etc. In this paper, a four parallel laser-based simultaneous measurement (FPL-SM) method is proposed for measuring 6-DOF errors of rigid bodies with translational motion. First, a FPL-SM device is introduced. Its four laser heads form a rectangle, which is perpendicular to the movement direction of the measured linear displacement. Second, identification formulas for all geometrical errors in rigid bodies with translational motion are presented based on the relative positions of the four lasers. Based on the readings of the four lasers, angular errors and corresponding straightness errors are calculated for the direction of motion around the other two linear motions. As the two parallel sides of the rectangle are in different planes, the straightness errors of the two planes are different. The rolling angular error in the direction is expressed as the difference between the straightness errors of the two planes divided by the distance between the two planes. Six fundamental errors for rigid bodies with translational motion are obtained by four lasers in a single setting of the device. For multiple rigid bodies with mutually perpendicular translational motion, the squareness error is calculated by fitting to the actual direction of motion. Finally, experiments were carried out on the SmartCNC_DRDT five-axis machine tool and 21 geometric errors were determined for three translational axes. Error compensation was carried out using the generated machine tool geometric error data to verify the effectiveness of the proposed FPL-SM method. In addition, geometric errors and thermal errors of the Z axis of the GTI-2740 machine tool are measured based on the FPL-SM method.

Topology optimization design of three-dimensional multi-material and multi-body structure based on irregular cellular hybrid cellular automata method.

In recent years, Hybrid Cellular Automata Method (HCAM) has been successfully applied to solve structural topology optimization problems. However, there was no report on HCAM research of three-dimensional composite structure composed of multiple materials and multiple bodies. Therefore, in this paper, three-dimensional non-cube cells of irregular size (such as tetrahedral cells with adaptive changes inside length) and Finite Element Method (FEM) are introduced to extend HCAM, which is better and more flexibly to fit complex geometric shapes. Furthermore, a better structure configuration of multi-material and multi-body structure is obtained. The typical example study showed that the proposed topology optimization method could effectively remove the redundant materials of multi-material and multi-body structure, and the optimized structure configuration could still meet the requirements of the original condition after geometric reconstructed. Thus it provided a reference for the intelligent design of other products.

Dramatic Responsivity Enhancement Through Concentrated H2 SO4 Treatment on PEDOT:PSS/TiO2 Heterojunction Fibrous Photodetectors.

In order to satisfy the growing requirements of wearable electronic devices, 1D fiber-shaped devices with outstanding sensitivity, flexibility, and stability are urgently needed. In this study, a novel inorganic-organic heterojunction fibrous photodetector (FPD) based on poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) and highly ordered TiO2 nanotube array is fabricated, which endows a high responsivity, large external quantum efficiency, and fast response speed at 3 V bias. To further ameliorate its performance in the self-powered mode, a facile acid treatment is adopted and the assembled H-PEDOT:PSS/TiO2 FPD demonstrates outstanding self-powered properties with ≈3000% responsivity enhancement (161 mA W-1 at 0 V under 365 nm irradiation, photocurrent enhancement of ≈50 times) compared with the untreated device. It is found that the concentrated H2 SO4 post-treatment helps decrease the tube wall thickness of TiO2 and partially removes the insulated PSS component in PEDOT:PSS, leading to enhanced conductivity and facilitated charge transportation, and thereby superb responsivity/photocurrent enhancement of self-powered H-PEDOT:PSS/TiO2 FPD. This low-cost and high-performance self-powered FPD shows high potential for applications in wearable electronic devices.

Effectiveness and safety of Chinese herbal formula combined with western medicine for ankylosing spondylitis: A protocol for systematic review and meta-analysis.

BACKGROUND: Ankylosing spondylitis (AS) is a chronic progressive inflammatory disease of the spine, which mainly invades the sacroiliac joint, spine, and large joints near the trunk, leading to fibrous and skeletal ankylosis and deformity, and can cause damage to the eyes, lung, cardiovascular, kidney and other organs. Chinese herbal formulas (CHF) is an important interventions of Traditional Chinese Medicine (TCM), and CHFs combined with western medicine are widely used in clinical practice to treat AS. METHODS: Eight databases will be systematically retrieved from their inceptions to March 2021. Only randomized controlled trials (RCTs) of CHFs combined with western medicine for AS treatment will meet the inclusion criteria. The primary outcomes we focus on include clinical effectiveness rate, TCM syndrome score, TCM symptom score, Bath ankylosing spondylitis disease activity index (BASDAI), Bath Ankylosing Spondylitis Functional Index (BASFI), Bath Ankylosing Spondylitis Metrology Index (BASMI), chest expansion, nocturnal spinal pain, adverse reactions, erythrocyte sedimentation rate (ESR), and C protein response (CRP). The research screening, data extraction, and risk of bias assessment will be performed independently by 2 researchers, and divergence will be solved by a third researcher. Revman 5.3 software will be used for meta-analysis. The confidence of evidence will be graded using grading of recommendations assessment, development, and evaluation (GRADE) algorithm and methodological quality will be assessed adopting risk of bias in systematic reviews (ROBIS). RESULTS: This systematic review (SR) will provide evidence-based medical evidence for AS therapy by CHF combined with western medicine and we will submit the findings of this SR for peer-review publication. CONCLUSIONS: This SR will provide latest and updated summary proof for assessing the effectiveness and safety of CHF combined with western medicine for AS. REGISTRATION NUMBER: INPLASY 202150089.

Effects of Treatment Setting on Outcomes of Flexibly-Dosed Intensive Cognitive Behavioral Therapy for Pediatric OCD: A Randomized Controlled Pilot Trial.

Introduction: Optimizing individual outcomes of cognitive-behavioral therapy (CBT) remains a priority. Methods: Youth were randomized to receive intensive CBT at a hospital clinic (n = 14) or within their home (n = 12). Youth completed 3 × 3 h sessions (Phase I) and up to four additional 3-h sessions as desired/needed (Phase II). An independent evaluator assessed youth after Phase I, Phase II (when applicable), and at 1- and 6-months post-treatment. A range of OCD-related (e.g., severity, impairment) and secondary (e.g., quality of life, comorbid symptoms) outcomes were assessed. Results: Families' satisfaction with the treatment program was high. Of study completers (n = 22), five youth (23%) utilized no Phase II sessions and 9 (41%) utilized all four (Median Phase II sessions: 2.5). Large improvements in OCD-related outcomes and small-to-moderate benefits across secondary domains were observed. Statistically-significant differences in primary outcomes were not observed between settings; however, minor benefits for home-based treatment were observed (e.g., maintenance of gains, youth comfort with treatment). Discussion: Intensive CBT is an efficacious treatment for pediatric OCD. Families opted for differing doses based on their needs. Home-based treatment, while not substantially superior to hospital care, may offer some value, particularly when desired/relevant. Clinical Trial Registration: www.ClinicalTrials.gov; https://clinicaltrials.gov/ct2/show/NCT03672565, identifier: NCT03672565.

Pareto distributions in online casino gambling: Sensitivity to timeframe and associations with self exclusion.

The Pareto effect (also known as the 80/20 rule) describes a skewed distribution of engagement that is observed for many products. In this study, we investigated Pareto estimates for online casino gambling, and tested their association with voluntary self-exclusion (VSE) as a marker of gambling harm, and examined their sensitivity to varying time windows. We used one year of betting data from the eCasino section of a provincially-run gambling website in British Columbia, Canada. The data contained 30,920 account holders who placed at least one bet on the platform from October 2014 to September 2015. The top 20% most engaged gamblers accounted for 92% (based on total number of bets) and 90% (based on net losses) of eCasino gambling activity over the year. The top 20% of online gamblers displayed higher levels of VSE enrolment than the remaining 80% (total bets: 13% vs 7%; net losses: 16% vs 6%, respectively). Pareto estimates increased with longer time windows, from one month to one year (total bets: 80% to 92%; net losses: 81% to 90%, respectively). This accumulation was driven by the relative loyalty of the most engaged gamblers, coupled with the influx of new and more transient gamblers on a month-to-month basis. These data strengthen links between concentrations of engagement with online products and measures of harm, but also highlight the dynamic nature of these estimates. One year estimates are preferable for estimating the degree of concentration.

Pseudohomogeneous metallic catalyst based on tungstate-decorated amphiphilic carbon quantum dots for selective oxidative scission of alkenes to aldehyde.

Herein, we present an interesting role of tungstate-decorated amphiphilic carbon quantum dots (A-CQDs/W) in the selective oxidative cleavage of alkenes to aldehydes. In this work, for the first time, we disclose an unprecedented tungstate-based oxidative system incorporating A-CQDs as a bridge to the homogeneous catalyst for selective and efficient cleavage of a wide substrate scope of alkenes into aldehydes. The A-CQDs/W were synthesized via a one-step hydrothermal synthesis approach using 1-aminopropyl-3-methyl-imidazolium chloride and stearic acid for the surface modification, following by anion-exchange to immobilize WO4-2 to A-CQDs. The A-CQDs/W act as a pseudohomogeneous metallic catalyst (PMC) for selective oxidative scission of alkenes under phase transfer catalysts (PTC) free condition without over oxidation to acids, using water and H2O2 as a green oxidant. Thanks to the sub-nanometric size and novel engineered chemical structure, this PMC and reactants are in the same phase, besides they can be easily isolated from each other by extraction processes. The synthesized PMC exhibited excellent solubility and stability in various solvents. Interestingly, the system's high conversion efficiency was preserved even after eight catalytic cycles indicating the recyclability of the synthesized PMC. We believe that this study provides a significant and conceptually novel advance in oxidative cleavage chemistry.

DIR-DBTnet: Deep iterative reconstruction network for three-dimensional digital breast tomosynthesis imaging.

PURPOSE: The goal of this study is to develop a three-dimensional (3D) iterative reconstruction framework based on the deep learning (DL) technique to improve the digital breast tomosynthesis (DBT) imaging performance. METHODS: In this work, the DIR-DBTnet is developed for DBT image reconstruction by mapping the conventional iterative reconstruction (IR) algorithm to the deep neural network. By design, the DIR-DBTnet learns and optimizes the regularizer and the iteration parameters automatically during the network training with a large amount of simulated DBT data. Numerical, experimental, and clinical data are used to evaluate its performance. Quantitative metrics such as the artifact spread function (ASF), breast density, and the signal difference to noise ratio (SDNR) are measured to assess the image quality. RESULTS: Results show that the proposed DIR-DBTnet is able to reduce the in-plane shadow artifacts and the out-of-plane signal leaking artifacts compared to the filtered backprojection (FBP) and the total variation (TV)-based IR methods. Quantitatively, the full width half maximum (FWHM) of the measured ASF from the clinical data is 27.1% and 23.0% smaller than those obtained with the FBP and TV methods, while the SDNR is increased by 194.5% and 21.8%, respectively. In addition, the breast density obtained from the DIR-DBTnet network is more accurate and consistent with the ground truth. CONCLUSIONS: In conclusion, a deep iterative reconstruction network, DIR-DBTnet, has been proposed for 3D DBT image reconstruction. Both qualitative and quantitative analyses of the numerical, experimental, and clinical results demonstrate that the DIR-DBTnet has superior DBT imaging performance than the conventional algorithms.