Types Of Segments Research Articles

Search Steering in Two-Sided Platforms

Many two-sided platforms are known to steer customers toward certain products based on their willingness to pay. In this article, we study platforms’ incentives to adopt this type of market segmentation and present conditions under which this can generate distortions that negatively impact the surplus from buyers and sellers. In our environment, a monopolistic platform matches sellers with buyers. Upon being matched, each pair of buyer and seller negotiates prices. If they choose to transact, the platform receives a commission fee proportional to the value of the transaction plus a flat fee per transaction. The platform is assumed to have full information about customers’ and sellers’ outside options. We show that, as long as the market is in excess supply or as long as there is a crossing between the demand and supply curves , the platform’s optimal matching is suboptimal from the perspective of buyers and sellers.

Distribution and neurochemical characterisation of neurons containing neuregulin 1 in the enteric nervous system within the porcine small intestine

Abstract Introduction The enteric nervous system (ENS) in the wall of the gastrointestinal tract is complex and comprises many neurons, which are differentiated in terms of structure, function and neurochemistry. Neuregulin 1 (NRG 1) is one of the neuronal factors synthesised in the ENS about the distribution and functions of which relatively little is known. The present study is the first description of the distribution of NRG 1 in the ENS in various segments of the porcine small intestine. Material and Methods Fragments were excised from the duodenum, jejunum and ileum of five euthanised Piétrain × Duroc sows, 18–20 kg in weight and eight weeks of age. Paraformaldehyde-fixed and dehydrated tissue was sectioned and double-labelling immunofluorescence was performed using Alexa Fluor-conjugated secondary antibodies to visualise neuregulin 1 and its colocalisation with vasoactive intestinal polypeptide (VIP), galanin (GAL), and the neuronal isoform of nitric oxide synthase (nNOS) in the myenteric and inner and outer submucosal plexuses, with PGP 9.5 serving as a pan-neuronal marker. Results Neuregulin 1 was observed in all enteric plexuses in each segment of the small intestine. The percentage of NRG 1-positive neurons ranged from 8.38 ± 0.55% of all neurons in the jejunal inner submucous plexus to 21.52 ± 0.98% in the duodenal myenteric plexus. Cells which were NRG 1-positive also contained VIP, GAL and nNOS in all segments of the small intestine to a degree which varied by small intestine segment and enteric plexus type. Conclusion The results indicate that NRG 1-positive neurons are present in the ENS of the porcine small intestine and differ significantly neurochemically, which may suggest a multifaceted role for NRG-1 in the controlling of the small intestine activity.

Modeling and Estimating the Effect of a Mix of Varying Levels of Automated Vehicles on Operational Performance of Urban Freeways

Automated vehicles (AVs) will likely influence various aspects of the existing transportation system in the next few decades. Existing literature documents the operational benefits of AVs at different penetration rates. However, estimating the effect of the mix of different levels of AVs on the operational performance of traffic flow has not been explored in the past. This study employs a microsimulation approach to model and estimate the potential effect of varying levels of AVs on the operational performance of freeways. The proposed approach involves a two-step process for calibrating the simulation model. In the first step, the model is calibrated from an operational perspective. In the second step, the calibration is performed from a safety perspective. Thirteen scenarios were generated considering varying penetration rates of different levels of AVs. Congestion index (CI), buffer time (BT), travel time uncertainty (TTU), and delay were computed for each scenario and segment type. The estimations indicate that increasing the penetration of level 3 to level 5 AVs significantly reduces CI, BT, TTU, and delay. In contrast, the effect of level 1 and 2 AVs on freeway operational performance is negligible. Notably, the operational benefits are more pronounced with higher penetration of level 3 and higher AVs. Additionally, the reduction in delay is greater on interchange segments compared with basic freeway segments. The study findings are valuable insights concerning the operational performance of freeways under varying penetration of different levels of AVs, assisting practitioners in formulating AVs-inclusive policies.

Predictors of breast cancer HER2-receptor positivity by MRI intuitive imaging features

BackgroundToday, breast cancer is the most diagnosed cancer worldwide. There are many different clinical presentations, radiological characteristics, and histological types of breast cancer. HER2 is overexpressed in a significant number of breast cancer cases reaching 20% of all breast cancers, and its overexpression is seen directly proportionate with a poor outcome and prognosis.MethodsWe started this cross-sectional research from January 2022–December 2023 on 202 breast cancer patients who had 220 lesions. The molecular subtypes of the different lesions were determined in all the included cases. Magnetic resonance imaging (MRI) studies were conducted in all included cases. The MRI parameters included conventional MRI, diffusion-weighted analysis, and dynamic post-contrast T1-weighted imaging.ResultsThe prevalence of irregular margins (P < 0.001), linear and segmental distribution (P = 0.044), heterogeneous pattern (P < 0.001), and type 2 curve was statistically significantly higher in the HER2-positive lesions. Nipple infiltration incidence showed statistically significant elevation in the HER2-positive lesions (P = 0.017). The lesions’ ADC and perilesional ADC in the HER2-positive lesions were also statistically significantly elevated. The best cutoff point of ADC to detect lesions with positive HER2 expression was > 0.885 × 10–3 mm2/s, with 65.7% sensitivity and 60% specificity, with a statistically significant value (p = 0.005).ConclusionsMagnetic resonance imaging of breast imaging is a promising noninvasive method for identifying breast tumors with the HER2 molecular subtype. Combining various radiological features by MRI may provide a conclusion for recognizing positive HER2 lesions.

Widening the price gap: the effect of the Netherlands' 2020 tax increase on tobacco prices.

The public health impact of a tobacco tax increase depends on the extent to which the industry passes the increase onto consumers, also known as tax-pass through. In 2020, the Netherlands announced tax increases aimed to increase the retail price by €1 per 20 factory-made cigarettes and €2.50 per 50 grams of roll-your-own tobacco. This study examines the pass-through rate after the tax increase, and whether this differed by type of tobacco and brand segment. Self-reported prices of 117 tobacco brand varieties (cigarettes=72, roll-your-own=45) pre- and post-tax increase were extracted from the 2020 International Tobacco Control (ITC) Netherlands Surveys (n=2959 respondents). We calculated the tax pass-through rate per variant, examining differences between type of tobacco and brand segments. On average, cigarette prices increased by €1.12 (SD=0.49) (112% of €1) and roll-your-own prices by €2.53 (SD=0.60) (101% of €2.50). Evidence of differential shifting across segments was found, with evidence of overshifting in non-discount varieties. The average price of discount varieties increased with €0.20 less than non-discount varieties. Similarly, the net-of-tax price decreased in discount varieties (cigarettes=-€0.02; roll-your-own=-€0.05), but increased in non-discount varieties (cigarettes= +€0.14; roll-your-own= +€0.20). Despite the large tax increase, the industry increased prices in line or above the required level. Through differential shifting, the price gap between discount and non-discount varieties has widened, which may reduce the public health impact of the tax increase. Measures aimed at reducing price variability should be strengthened in taxation policy, such as the European Tobacco Tax Directive. We found that the industry used differential shifting after a significant tobacco tax increase in the Netherlands. Prices increased more than required in higher-priced products, but not in lower-priced products. This pattern was found both for factory-made cigarettes and roll-your-own tobacco. Through differential shifting, the industry undermines the potential public health impact of tobacco tax increases, by offering a relatively cheaper alternative, which discourages people to quit or reduce consumption. The revision of the European Tobacco Tax Directive (TTD) provides an opportunity to address the widening price gap - both between and within product segments - across the European Union.

Practical three-dimensional path following and control for unmanned combat aerial vehicles based on expansion of L1+ guidance logic and disturbance rejection

An effective virtual-target-based three-dimensional path-following algorithm is proposed for unmanned combat aerial vehicles, which extends from the planar [Formula: see text] guidance. The separated implementation of the planar guidance law in two perpendicular planes provides the longitudinally-laterally decoupled acceleration commands. In order to obtain a non-unique virtual-target-point, a numerical iterative method using auxiliary path-related variables is proposed. Moreover, two protection improvements are discussed for real-word implementation: one involves the modification of adaptive [Formula: see text] length for vehicle position far away from the desired path; the other involves a switching strategy for multi-segment paths. The improved algorithm eliminates complex coordinate transformation and easily connects different types of path segments. For the control loop, technology enhanced with the active disturbance rejection control was used to facilitate the design of a bank-to-turn autopilot. For the pitch and roll channels, a rate-damping augmentation loop was used first to transform the original system into a generalized plant. Then the second-order active disturbance rejection control was structured to estimate the total disturbance, including time-varying dynamics, model mismatch, and coupling of channels, making the system an ideal integral-series type. The non-smooth optimization technique in the H-infinity methodology was used to facilitate tuning of the fixed-structure active disturbance rejection control.

Mechanical Performances of Concrete-Filled Steel Pipe Composite Segments in Complex Geological Conditions

When shield tunnels are under complex geological conditions, tunnel damage, decreased structural performance, and shield tunnel deformation and destruction may occur. Therefore, a new type of composite segment and combined splicing joint were suggested and experimentally investigated in this study. According to the test results, the new composite segment effectively enhanced the load capacity of the segment, and the yield and ultimate loads of the segment were increased. Compared with the reference specimen, the ultimate load capacities of the proposed segments with different numbers were 23.8%, 50.0%, and 64.3% greater. Moreover, the combined splicing joint enhanced the initial bending stiffness and load capacity of the segment joint, reduced the opening displacement, and improved the rotational stiffness of the segment joint. The addition of a plug-in joint at the segment joint increased its load capacity by approximately 25%. A parametric study showed that the number and posit ion of the plug-in joint clearly affected the load capacity of the segment joint. In addition to the above test results, reasonable theoretical formulas for the new composite segment and combined splicing joint are given in this paper.

An Overview of Pharmaceutical Applications and In vitro Micropropagation Techniques for Rare and Endangered Plant Species

Many rare and endangered plant species possess valuable secondary metabolites with pharmacological applications. These bioactive compounds are often integral to traditional medicine systems, highlighting the cultural significance of these plants. The health benefits of many medicinal species are not fully validated by contemporary scientific research, and some may be facing extinction due to habitat loss, overharvesting or climate change. This situation highlights the urgent need for effective conservation strategies of the species and sustainable cultivation methods. Micropropagation is a valuable technique for producing large numbers of plants from a single explant, significantly aiding in the conservation and commercial cultivation of rare species. Among the various types of explants, shoot tips and nodal segments have been identified as the most effective explants for micropropagation. These explants can be induced to generate multiple shoots in Murashige and Skoog (MS) medium containing Benzyl aminopurine (BAP). Thidiazuron (TDZ), Kinetin (KIN), or 2,4-Dichlorophenoxyacetic acid (2,4-D) are commonly used in MS medium to promote shoot and root development in both direct and indirect organogenesis processes. Rooting of the plantlets was typically achieved using MS medium either supplemented with Indole-3-butyric acid (IBA) or devoid of auxins, depending on the species and the specific requirements for rooting.

Consonant and vowel production in children with cochlear implants: acoustic measures and multiple factor analysis

IntroductionThe acoustic limitations of cochlear implants (CIs) can lead to perceptual limitations and consequently to imprecise phonological representations and production difficulties. The aim of the study is to document the phonological and phonetic skills of children with CIs and their typically hearing peers. Phonetically, three types of segments were targeted, each characterized by contrasting acoustic information: nasal/oral vowels, fricative segments, and voiced/voiceless stops.MethodsForty-seven typically hearing children (TH) and 23 children with CIs performed a picture-naming task. Productions were analyzed to obtain phonological measures (percentages of correct phonemes, types of errors), and various acoustic measures were collected to characterize the productions on the three types of segments investigated. Multiple factor analyses were conducted to study productive profiles on the various acoustic measures, and the dimensions were correlated with phonological measures.ResultsThe results showed lower performance in lexical (target word retrieval) and phonological (percentages of correct phonemes) skills among children with CIs (CI group), although with better performances among children exposed to CS. Acoustically, children in the CI group exhibited productions significantly different from those of the TH group in terms of the distinction of fricative consonants, marking nasalization through nasal resonance cues, and in the production of voiceless stops. However, the CI group demonstrated compensatory strategies (lengthening of VOT for voiced stops, marking of nasalization through oropharyngeal configuration cues).ConclusionsThe results indicate that children with CIs are at risk of experiencing difficulties in both phonetic and phonological domains. However, there are opportunities for compensation through the exploitation of acoustic cues better coded by the CI and/or through perceptual means (utilization of visual cues).

Refined kinetic model for the simulation of polycarbonate synthesis via continuous melt transesterification

This paper establishes a kinetic model for the polymerization and condensation occurring during the melt transesterification of bisphenol A (BPA) and diphenyl carbonate (DPC). The model is based on molecular fragments and functional groups, treating polymers as an assembly of four types of chain segments. This study delves into the reaction mechanisms underlying the polycondensation of BPA and DPC, offering fresh perspectives on the process. Kinetic equations pertinent to the polycondensation mechanism were deduced from the analysis and then rigorously tested against experimental data to ascertain their validity. Kinetic constants emerged through the fitting of this experimental data, lending credence to the model’s accuracy. Utilizing the Aspen Plus software, the model was applied to simulate the annual production of 100,000 tons of polycarbonate (PC). The simulation facilitated the optimization of the operating conditions for each reactor, yielding valuable insights for scaling up to industrial production.

The role of clivus and atlanto-occipital lateral mass height in basilar invagination with or without atlas occipitalization.

Basilar invagination (BI) is a common deformity. This study aimed to quantitatively evaluate the height of clivus and atlanto-occipital lateral mass (LM) in patients with BI with or without atlas occipitalization (AOZ). We evaluated 166 images of patients with BI and of controls. Seventy-one participants were control subjects (group A), 68 had BI with AOZ (group B), and 27 had BI without AOZ (group C). Parameters were defined and measured for comparisons across the groups. Multiple linear regression analysis was used to test the relationship between Chamberlain's line violation (CLV) and the clivus height ratio or atlanto-occipital LM height.Based on the degree of AOZ, the lateral masses in group B were classified as follows: segmentation,incomplete AOZ,complete AOZ. From groups A to C, there was a decreasing trend in the clivus height and clivus height ratio. There was a linear negative correlation between the clivus height ratio and CLV in the three groups. Generally, the atlanto-occipital LM height followed the order of group B < group C < group A. The atlanto-occipital LM height was included only in the equations of groups B. There were no cases of atlantoaxial dislocation (AAD) in group C.There was a decreasing trend in LM height from the segmentation type to the complete AOZ type in group B. BI can be divided into three categories: AOZ causes LM height loss; Clivus height loss; Both clivus and LM height loss. The clivus height ratio was found to play a decisive role in both controls and BI group, while the atlanto-occipital LM height loss caused by AOZ could be a secondary factor in patients with BI and AOZ. AOZ may be a necessary factor for AAD in patients with congenital BI.The degree of AOZ is associated with LM height in group B.

Classification and Treatment Strategies of Tibial Tubercle Fractures in Adults.

Tibial tubercle is a crucial player in maintaining the structural integrity and functional stability of the knee joint. Currently, there is no standardized protocol for the classification and treatment of tibial tubercle fractures in adults. This study analyzed the incidence and treatment strategies of tibial tubercle fractures in adults according to the four-column and nine-segment classification system. Data of patients with proximal tibial fractures involving tibial tubercle fractures who were treated at our hospital from August 2007 to March 2023 were retrospectively reviewed. The fractures were classified using the AO/OTA classification and four-column and nine-segment classification systems, and the treatment protocol (surgically treated or conservatively treated) was recorded. The number and distribution proportion of patients were counted. A two-sided t-test was conducted to determine the significance of differences between the gender and sides. In total, 169 tibial tubercle fractures were found in 1484 proximal tibial fractures. According to the AO/OTA classification, seven of the 169 patients, (4.1%) were type A, 36 patients (21.3%) were type B, and 126 patients (74.6%) were type C. According to the four-column and nine-segment classification, type 1 cleavage without free fragments was the most common type of fracture (93/169, 55.0%), followed by type 2 dissociative segmental fragments (48/169, 28.4%) and type 3 comminuted fractures (28/169, 16.6%). Overall, 139 of the 169 proximal tibial fractures with tuberosity involvement were treated surgically. Among them, additional fixation of the tubercle fragment was performed in 52 fractures. The incidence of tibial tubercle fractures involved in proximal tibial fractures was approximately 11.4% (169/1484) in adults, and approximately one-third of the tubercle bone fragment required additional fixation (30.8%, 52/169). The injury types in the four-column and nine-segment classifications are helpful for accurately judging and making treatment-related decisions for tibial tubercle fractures.

Preparation and Structural-Thermodynamical Investigation of Renewable Copolyesters Based on Poly (Ethylene Succinate) and Polyisosorbide.

A series of novel renewable copolymers based on poly(ethylene succinate) (PESu) and poly(isosorbide succinate) (PISSu), with the Isosorbide (Is)/PESu molar ratio varying from 5/95 to 75/25, were synthesized in-situ and studied in this work. A sum of characterization techniques was employed here for the structural and thermo-dynamical characterization. The sophisticated technique of dielectric spectroscopy, along with proper analysis, enabled the molecular dynamics mapping of both the local and segmental types, which is presented for such materials for the first time. With increasing the Is fraction, shorter copolymeric entities were gradually formed. Based on the overall findings, the systems were found to be homogeneous, e.g., exhibiting single glass transitions, with the two polymer segments being found to be excellently distributed. The latter is indirect, although strong, evidence for the successful copolymerization. The thermal degradation mechanism for the copolymers was exhaustingly explored employing analytical pyrolysis. The systems exhibited, in general, good thermal stability, according to the thermogravimetric analysis. Confirming one of the initial scopes for the present systems, isosorbide plays here the role of hardener (PISSu) over the soft polymer (PESu), and this is reflected in the monotonic increase of the glass transition temperature, Tg, from -16 to ~56 °C. The introduction of Is results in an increase in constraints (hardening of the matrix), while there seems to be an overall densification of the polymer (decrease of the free volume).

Pedestrian and Car Occupant Crash Casualties Over a 9-Year Span of Vision Zero in New York City

Vision Zero has been increasingly embraced by jurisdictions across the United States. Existing research primarily focuses on the theoretical principles and effectiveness of specific engineering measures. However, there is limited understanding of the holistic effects of Vision Zero treatments, in the context of street type and urban environment. We developed a street typology framework to categorize street segments using four design and operational features: street width, traffic direction (one- versus two-way), number of travel lanes, and presence of on-street parking. We applied a sample-based partitioning around medoids algorithm to classify 90,327 street segments in New York City. This process results in six distinctive types of street segment. To integrate neighborhood-level factors (e.g., land use variables and sociodemographics), we aggregated street segments of a given street type for each neighborhood. Negative binomial regression models were developed for pedestrian and car occupant crash injuries and fatalities separately for three periods: 2014 to 2016, 2017 to 2019, and 2020 to 2022. Our findings showed that street-segment groups with narrower, two-way sections and greater tree canopy coverage were significantly associated with a lower risk of casualties for both pedestrians and motorized users. Street-segment groups located in neighborhoods with a larger percentage of African American and Hispanic American residents experienced a significantly greater risk of casualties. Vision Zero treatments had mixed effects on safety outcomes. Streets treated with leading pedestrian intervals showed a lower risk of casualties. Neighborhood- and arterial slow zones were associated with a lower risk of car occupant casualties.

Experimental Investigation on a Water Diversion Shield Segment Using a Newly Developed Model Test Chamber

Jinan City in China is known for its abundant spring water, and the protection of underground spring water transport channels is a key issue that needs to be paid attention to in Jinan subway construction. In areas where underground spring water transport channels are easily disturbed, when the shield tunnel passes through a composite formation with a permeable layer in the middle and an impermeable layer in the upper and lower parts, the underground spring water transportation channel is blocked, the spring veins are damaged, and the underground spring water is blocked in the upstream, resulting in an increase in the water pressure difference on both sides of the tunnel. In this paper, based on the working principle of a new type of pipe segment with a diversion function, a diversion function pipe model test box is designed and fabricated. Using this model box, the working state of the diversion function pipe segments is simulated. An earth pressure box and pore water pressure gauges are embedded in the model box to measure the earth pressure and pore pressure around the pipe under seepage unsymmetrical pressure. Strain gauges are attached in a circular shape on the inner side of the pipe to measure and calculate the strain and stress of the pipe. Through model tests, the effective repair of the diversion pipe on blocking groundwater flow and the relief effect of the unsymmetrical pressure of the pipe are verified.

Intelligent diagnostic model for pterygium by combining attention mechanism and MobileNetV2.

To evaluate the application of an intelligent diagnostic model for pterygium. For intelligent diagnosis of pterygium, the attention mechanisms-SENet, ECANet, CBAM, and Self-Attention-were fused with the lightweight MobileNetV2 model structure to construct a tri-classification model. The study used 1220 images of three types of anterior ocular segments of the pterygium provided by the Eye Hospital of Nanjing Medical University. Conventional classification models-VGG16, ResNet50, MobileNetV2, and EfficientNetB7-were trained on the same dataset for comparison. To evaluate model performance in terms of accuracy, Kappa value, test time, sensitivity, specificity, the area under curve (AUC), and visual heat map, 470 test images of the anterior segment of the pterygium were used. The accuracy of the MobileNetV2+Self-Attention model with 281 MB in model size was 92.77%, and the Kappa value of the model was 88.92%. The testing time using the model was 9ms/image in the server and 138ms/image in the local computer. The sensitivity, specificity, and AUC for the diagnosis of pterygium using normal anterior segment images were 99.47%, 100%, and 100%, respectively; using anterior segment images in the observation period were 88.30%, 95.32%, and 96.70%, respectively; and using the anterior segment images in the surgery period were 88.18%, 94.44%, and 97.30%, respectively. The developed model is lightweight and can be used not only for detection but also for assessing the severity of pterygium.

Steganography in QR Codes—Information Hiding with Suboptimal Segmentation

This paper describes a new steganographic method for QR codes. Unlike most information-hiding techniques in this field, it does not rely on the error correction property. Instead, it uses the segmentation feature of QR codes. Encoding of data in a QR code is achieved by creating segments of specific modes, chosen according to data type in order to save space. However, the segmentation does not have to be optimal. A secret message may be embedded into a QR code by selecting an alternative segment type. The presented method generates valid QR codes that may be decoded with standard readers. The solution has been tested using several QR decoders, and it has been confirmed that only the regular message was returned. Additionally, the error correction quality of produced codes is not diminished. The described algorithm is suitable for either digital or printed media, and in both cases, QR codes retain secret data.

O-260 Identifying seminiferous tubules for sperm retrieval during microdissection testicular sperm extraction (M-TESE) using deep learning

Abstract Study question Is it possible to utilize artificial intelligence (AI) in the selection of seminiferous tubules for sperm retrieval during microdissection testicular sperm extraction (M-TESE)? Summary answer AI algorithm was able to segment seminiferous tubules deemed to be good candidates for sperm retrieval with IoU of 0.746 and F1 score of 72.5%. What is known already M-TESE is an advanced surgical procedure reserved for sperm retrieval in men with non-obstructive azoospermia (NOA). Meta-analysis have shown M-TESE might be superior in relation to sperm retrieval rates and postsurgical complications when compared to conventional techniques. Limitations of the technique are the relatively long learning curve for the surgeons and the longer intraoperative time required to identify the tubules with active spermatogenesis. Convolutional neural networks (CNNs) have been shown to successfully identify areas of interest in medical images such as CT and MRI scans. The possibility of utilizing trained CNNs in M-TESE procedures has so far not been studied. Study design, size, duration This is a cross sectional study analyzing image data gathered during M-TESE procedures including the first five men enrolled in a prospective study designed specifically to test the utilization of AI in the treatment of NOA. All participants signed written informed consent. Images were collected intraoperatively with low and high resolution cameras according to predefined protocol. Participants/materials, setting, methods CNN model with down and upsampling architecture was trained using patch-based technique with corresponding labelled truth image pairs based on combination of semi-automated hue saturation value thresholding and manual segmentation of seminiferous tubules. Tubules were allocated into two different classes by the operating surgeon according to the visual perception of their morphology as type 1 (i.e. larger, opaque, good candidates for micro dissection) and type 2 (i.e. sclerotic or atrophic; unlikely to harbor active spermatogenesis). Main results and the role of chance CNN models were trained on 1809 patches with corresponding ground truth segmented images. Two algorithms were tested: the first was trained solely to detect and semantically distinguish type 1 seminiferous tubules. The second was trained to semantically segment the major anatomical structures: tunica albuginea, testicular parenchyma, blood vessels; lobules and the two types of seminiferous tubules describe above. Validation was performed on 988 image patches not previously shown to the algorithm. After grid search for optimal learning rate and augmentation the first algorithm was able to segment type 1 tubules with F1 score of 72.5% and Jaccard Index (IoU) of 0.746. Training took 856 minutes on 48 core high performance computer (HPC) equipped with single graphics processing unit (GPU). Same computational environment was used in the training of the second algorithm. This model was able to segment anatomical structures such as parenchyma (IoU=0.732) and testicular lobules (IoU=0.683) but performed sub optimally on the clinically relevant type 1 tubules (IoU=0.432). The first trained algorithm was able to segment a single high resolution surgical image in 3.4 seconds on an HPC. However, the same procedure took 5.5 minutes on standard desktop computer with 8 core Intel processor without GPU. Limitations, reasons for caution The number of patients is relatively small and therefore more training data would be needed to achieve robust performance. Training data were labelled by single surgeon limiting the generalizability and possibly biasing the selection process. The need of HPC environment for real time segmentation can limit the clinical use. Wider implications of the findings This pilot study shows the potential of AI to help in choosing suitable tubules for micro dissection, shortening the learning curve for young andrological surgeons. The access to cluster based computation is getting easier by the day and can soon allow instant intraoperative AI segmentation, thus shortening the surgical procedure. Trial registration number NA

Cervical cancer segmentation based on medical images: a literature review.

Cervical cancer clinical target volume (CTV) outlining and organs at risk segmentation are crucial steps in the diagnosis and treatment of cervical cancer. Manual segmentation is inefficient and subjective, leading to the development of automated or semi-automated methods. However, limitation of image quality, organ motion, and individual differences still pose significant challenges. Apart from numbers of studies on the medical images' segmentation, a comprehensive review within the field is lacking. The purpose of this paper is to comprehensively review the literatures on different types of medical image segmentation regarding cervical cancer and discuss the current level and challenges in segmentation process. As of May 31, 2023, we conducted a comprehensive literature search on Google Scholar, PubMed, and Web of Science using the following term combinations: "cervical cancer images", "segmentation", and "outline". The included studies focused on the segmentation of cervical cancer utilizing computed tomography (CT), magnetic resonance (MR), and positron emission tomography (PET) images, with screening for eligibility by two independent investigators. This paper reviews representative papers on CTV and organs at risk segmentation in cervical cancer and classifies the methods into three categories based on image modalities. The traditional or deep learning methods are comprehensively described. The similarities and differences of related methods are analyzed, and their advantages and limitations are discussed in-depth. We have also included experimental results by using our private datasets to verify the performance of selected methods. The results indicate that the residual module and squeeze-and-excitation blocks module can significantly improve the performance of the model. Additionally, the segmentation method based on improved level set demonstrates better segmentation accuracy than other methods. The paper provides valuable insights into the current state-of-the-art in cervical cancer CTV outlining and organs at risk segmentation, highlighting areas for future research.

Multi-level time-varying causality analysis of secondary conflicts based on hazard-based duration models

Secondary conflicts occur frequently and would cause multi-vehicle collisions. In order to prevent multi-vehicle collisions, a better understanding of the factors that affect secondary conflict propagation is crucial. Previous studies have identified the influencing factors of primary conflicts’ occurrence, but have not explored the time-varying factors that affect secondary conflicts’ propagation. In addressing this gap, about 20,000 secondary conflicts are extracted from real trajectory dataset, and a multi-level variable system is established, including segment types, traffic status, front chain conflict status, and direct interaction behaviors. Further, a Kaplan-Meyer model and a random parameters hazard-based duration model are constructed to explore the single-factor and multiple-factor influence on the propagation of secondary conflicts, respectively. The results suggest that the first 2.6 s after a conflict is a critical post-monitoring period to prevent the secondary conflicts propagation. In addition, diverging and merging segments shorten the survival time of secondary conflicts by about 12%, indicating a higher occurrence probability of secondary conflicts near the ramps of expressways. More importantly, the front chain conflict status and the front direct conflict status reveal a different effect on the secondary conflicts. The high risk of chain conflict ahead would increase the occurrence probability of secondary conflicts, while the high risk of front conflict would decrease the probability. Overall, this research is of great significance to understand the influencing factors of secondary conflict and avoid secondary crashes.