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Extended reality (XR) refers to an umbrella of methods that allows users to be immersed in a three-dimensional (3D) or a 4D (spatial + temporal) virtual environment to different extents, including virtual reality (VR), augmented reality (AR), and mixed reality (MR). While VR allows a user to be fully immersed in a virtual environment, AR and MR overlay virtual objects over the real physical world. The immersion and interaction of XR provide unparalleled opportunities to extend our world beyond conventional lifestyles. While XR has extensive applications in fields such as entertainment and education, its numerous applications in biomedicine create transformative opportunities in both fundamental research and healthcare. This Primer outlines XR technology from instrumentation to software computation methods, delineating the biomedical applications that have been advanced by state-of-the-art techniques. We further describe the technical advances overcoming current limitations in XR and its applications, providing an entry point for professionals and trainees to thrive in this emerging field.

Despite ongoing efforts in cardiovascular research, the acquisition of high-resolution and high-speed images for the purpose of assessing cardiac contraction remains challenging. Light-sheet fluorescence microscopy (LSFM) offers superior spatiotemporal resolution and minimal photodamage, providing an indispensable opportunity for the in vivo study of cardiac micro-structure and contractile function in zebrafish larvae. To track the myocardial architecture and contractility, we have developed an imaging strategy ranging from LSFM system construction, retrospective synchronization, single cell tracking, to user-directed virtual reality (VR) analysis. Our system enables the four-dimensional (4D) investigation of individual cardiomyocytes across the entire atrium and ventricle during multiple cardiac cycles in a zebrafish larva at the cellular resolution. To enhance the throughput of our model reconstruction and assessment, we have developed a parallel computing-assisted algorithm for 4D synchronization, resulting in a nearly tenfold enhancement of reconstruction efficiency. The machine learning-based nuclei segmentation and VR-based interaction further allow us to quantify cellular dynamics in the myocardium from end-systole to end-diastole. Collectively, our strategy facilitates noninvasive cardiac imaging and user-directed data interpretation with improved efficiency and accuracy, holding great promise to characterize functional changes and regional mechanics at the single cell level during cardiac development and regeneration.

Variations in sales promotion in e-commerce impact online purchase decisions. Managers of e-commerce marketplaces must comprehend the effects of sales deviations on purchase decisions. We categorize sales promotion changes as either recognisable or unrecognisable to the consumer. We used the stimulus-organization-response model to assess the influence of diverse sales promotions influence consumer purchase decisions via the perceived attractiveness of the product. Using data from 587 online consumers we discovered distinct impacts between recognisable and unrecognisable changes on perceived attractiveness and purchase intention. Additionally, product value moderates these effects. Current research provides valuable insights with interesting theoretical and managerial implications. [ABSTRACT FROM AUTHOR]

Online retailers are providing customized logistics service to meet heterogeneous customer demand. However, the value of customized logistics service is not clear. We study conceptually and empirically how customized logistics service influences online customer post-purchase behavior, specifically e-satisfaction and e-loyalty. Primary data on customized logistics service were collected from an online field study involving direct observation. Secondary data on e-satisfaction and e-loyalty were collected from Bizrate.com. We used hierarchical multiple regression analyses and constrained nonlinear regression for empirical analysis. The results indicate that customized logistics service contributes significantly to e-satisfaction and, in turn, to e-loyalty. Furthermore, shipping rates significantly moderate the indirect effect of customized logistics service on e-loyalty through e-satisfaction. This research contributes to the understanding of the nature and consequences of customized logistics service in online retailing. Our findings underscore the effect of customized logistics service on e-satisfaction and e-loyalty, and the critical moderation effects of shipping rate on these relationships. Results from this study hold implications for the way online service operations managers employ logistics service strategy.

Molecular imaging along with 3-dimensional (3-D) or 4-D (3-D spatial + 1-D temporal) visualization is widely used in clinical diagnosis and surgical planning. However, the pre-defined perspective and confined manipulation limit the in-depth exploration and analysis in 3-D/4-D. To overcome this obstacle, we utilized virtual reality (VR) to interact with CT images of the cardiopulmonary system in a 3-D immersive environment. We implemented manipulative functionalities into the VR environment that altered the cardiopulmonary models to interactively generate new data analysis perspectives. We successfully sliced a CT cardiac model showing in-depth surface visualizations of the ventricles and atria. Our customized framework enables enhanced data interpretation interactivity of CT images and establishes a user-directed manipulative VR platform derived from imaging results for remote medical practices including training, education, and investigation.

The existing shelf layout methods do not explicitly consider the attention and relevancy of the commodity systematically and thus have failed to capture the invalid associations, resulting in poor sales impact and customer satisfaction. For such shortcomings, in this paper, we propose a mathematical programming approach for shelf layout problems based on comprehensive related value. First, we introduce the concepts of related value considering both attention and relevancy; second, we give the concept of adjacent utility value and the freedom of placement, and further analyze the impact of the same commodity on surrounding commodities due to different placement positions; third, we establish a new comprehensive related value-based commodity layout optimization model (CRV-CL) and provide the solution steps integrating with a genetic algorithm. Finally, we analyze the characteristics of CRV-CL through a specific case. The simulation results indicate the overall relevancy after applying the CRV-CL model. [ABSTRACT FROM AUTHOR]

As online social networks are reshaping the way users share their daily experiences, and the way business practitioners manage their marketing activities, crowdturfing has been emerging as a potential threat that concerns many users. If no proper measures are taken, it may result in a crisis, such as public opinion being misled. In general, crowdturfing refers to coordinated suspicious online behaviors, such as hiring online posters to propagandize online comments with mendacious contents or to spread gossip about their competitors. Through crowdturfing, the stakeholders can achieve their expected goals of manipulating the public opinion, which would further bring negative effects on both the Internet users and society.

Despite ongoing efforts in cardiovascular research, the acquisition of high-resolution and high-speed images for the purpose of assessing cardiac contraction remains challenging. Light-sheet fluorescence microscopy (LSFM) offers superior spatiotemporal resolution and minimal photodamage, providing an indispensable opportunity for the in vivo study of cardiac micro-structure and contractile function in zebrafish larvae. To track the myocardial architecture and contractility, we have developed an imaging strategy ranging from LSFM system construction, retrospective synchronization, single cell tracking, to user-directed virtual reality (VR) analysis. Our system enables the four-dimensional (4D) investigation of individual cardiomyocytes across the entire atrium and ventricle during multiple cardiac cycles in a zebrafish larva at the cellular resolution. To enhance the throughput of our model reconstruction and assessment, we have developed a parallel computing-assisted algorithm for 4D synchronization, resulting in a nearly tenfold enhancement of reconstruction efficiency. The machine learning-based nuclei segmentation and VR-based interaction further allow us to quantify cellular dynamics in the myocardium from end-systole to end-diastole. Collectively, our strategy facilitates noninvasive cardiac imaging and user-directed data interpretation with improved efficiency and accuracy, holding great promise to characterize functional changes and regional mechanics at the single cell level during cardiac development and regeneration. [ABSTRACT FROM AUTHOR]

The objective of the present study was to determine the prognostic value of sperm motility parameters and motion characteristics to predict in vitro fertilization (IVF) rate in the buffalo. Sperm motility parameters (%; motile, progressive, rapid and medium) and motion characteristics (path velocity = VAP, µm/sec; progressive velocity = VSL, µm/sec; curvilinear velocity = VCL, µm/sec; amplitude of lateral head = ALH, µm and beat cross frequency = BCF, Hz) of 5 buffalo bulls (Tag # 2, 4, 6, 11 and 12) were determined by Cell Motion Analyzer (CASA) at post dilution (PD), pre freezing (PF) and post thaw (PT) stages. IVF ability of individual bull was determined by cleavage rate (CR, %). Multiple regression analysis was used to determine the prognostic values of sperm motility parameters and motion characteristics for CR as a dependent variable. At PT, Bull 2 showed the highest (P

Imrana Masroor,1 Muhammad Azeemuddin,1 Saima Sakhawat,1 Madiha Beg,1 Saba Sohail,2 Rashid Ahmed,3 Irfan-Ul-Haq,4 Javed Mehboob51Radiology Department, Aga Khan University Hospital, 2Radiology Department, Civil Hospital, 3Advanced Radiology Clinic, 4Radiology Department, Pakistan Naval Station Shifa Hospital, 5Karachi Institute of Radiotherapy and Nuclear Medicine, Karachi, PakistanBackground: The purpose of this study was to evaluate mammography reports for diagnosed breast cancer cases in major government and private centers in Karachi, Pakistan, with respect to concordance with the Breast Imaging Reports And Data System (BI-RADS®) lexicon.Methods: A prospective, descriptive, multicenter study was conducted in the radiology sections of the Aga Khan University Hospital, Pakistan Naval Station Shifa Hospital, Advanced Radiology Clinic, Karachi Institute of Radiotherapy and Nuclear Medicine, and Civil Hospital Karachi between May and October 2010 after approval from the ethical review committee of Aga Khan University. Mammograms reported as BI-RADS category 4 and 5 were included in the study. Mammograms reported as BI-RADS category 0, 1, 2 and 3 were excluded. Fifty reports were collected from each center. Data were collected about the clinical indication, breast density, location and description of the lesion, calcification, and comments on axillary lymph nodes. This description was compared with the BI-RADS lexicon.Results: The mean age of the patients was 50 ± 12 years. The clinical indication, breast parenchymal density, lesion location, and presence of calcification were better described by the private centers, while description of lymph node status was better stated by the government centers. This difference was statistically significant, except for lesion description. The description of masses by the two reporting groups was comparable.Conclusion: Mammographic reporting of malignant breast lesions in the private sector is more in line with the BI-RADS lexicon, as compared with government sector hospitals in Karachi, Pakistan. Lymph node documentation was better in government sector reports.Keywords: breast cancer, BI-RADS®, mammography, public sector, private sector

The Emerald Ash Borer (EAB), Agrilus planipennis, Fairmaire, an Asian invasive alien buprestid has devastated tens of millions of ash trees (Fraxinus spp.) in North America. Foliar phytochemicals of the genus Fraxinus (Oleaceae): Fraxinus pennsylvanica (Green ash), F. americana (White ash), F. profunda (Bush) Bush. (Pumpkin ash), F. quadrangulata Michx. (Blue ash), F. nigra Marsh. (Black ash) and F. mandshurica (Manchurian ash) were investigated using HPLC-MS/MS and untargeted metabolomics. HPLC-MS/MS help identified 26 compounds, including phenolics, flavonoids and coumarins in varying amounts. Hydroxycoumarins, esculetin, esculin, fraxetin, fraxin, fraxidin and scopoletin were isolated from blue, black and Manchurian ashes. High-throughput metabolomics revealed 35 metabolites, including terpenes, secoiridoids and lignans. Metabolomic profiling indicated several upregulated putative compounds from Manchurian ash, especially fraxinol, ligstroside, oleuropin, matairesinol, pinoresinol glucoside, 8-hydroxypinoresinol-4-glucoside, verbenalin, hydroxytyrosol-1-O-glucoside, totarol and ar-artemisene. Further, dicyclomine, aphidicolin, parthenolide, famciclovir, ar-turmerone and myriocin were identified upregulated in blue ash. Principal component analysis demonstrated a clear separation between Manchurian and blue ashes from black, green, white and pumpkin ashes. The presence of defensive compounds upregulated in Manchurian ash, suggests their potential role in providing constitutive resistance to EAB, and reflects its co-evolutionary history with A. planipennis, where they appear to coexist in their native habitats.