128 research outputs found

    THEORIZING A TWO-SIDED ADOPTION MODEL FOR MOBILE MARKETING PLATFORMS

    Get PDF
    From a two-sided market perspective, this paper is aimed at proposing a conceptual model for analyzing user adoption behaviors towards mobile marketing platforms. Both the consumer side and the merchant side of the platforms are modeled based on extending classical theories with newly introduced factors reflecting cross network effects, and the two sides are integrated in the overall model which reveals the dynamic interaction between the evolution processes of the two user groups through the platform. An experimental investigation and a survey study are conducted to test the consumer side and the merchant side of the model, respectively, both using the structural equation modeling (SEM) method for statistic analysis. Results from the empirical tests demonstrate that the two-sided perspective is promising for interpreting the adoption and evolution mechanisms of mobile marketing platforms. The proposed model extends the current research theme of information systems adoption to a more comprehensive viewpoint of two-sided markets, while contributes to the literature of two-sided market theories by introducing behavioral considerations

    The protective effects of flavonoids and carotenoids against diabetic complications—A review of in vivo evidence

    Get PDF
    open access articleDiabetes mellitus is a chronic metabolic disorder caused either by inadequate insulin secretion, impaired insulin function, or both. Uncontrolled diabetes is characterized by hyperglycemia which over time leads to fatal damage to both macro-and microvascular systems, causing complications such as cardiovascular diseases, retinopathy and nephropathy. Diabetes management is conventionally delivered through modifications of diet and lifestyle and pharmacological treatment, using antidiabetic drugs, and ultimately insulin injections. However, the side effects and financial cost of medications often reduce patient compliance to treatment, negatively affecting their health outcomes. Natural phytochemicals from edible plants such as fruits and vegetables (F&V) and medicinal herbs have drawn a growing interest as potential therapeutic agents for treating diabetes and preventing the onset and progression of diabetic complications. Flavonoids, the most abundant polyphenols in the human diet, have shown antidiabetic effects in numerous in vitro and preclinical studies. The underlying mechanisms have been linked to their antioxidant, anti-inflammatory and immunomodulatory activities. Carotenoids, another major group of dietary phytochemicals, have also shown antidiabetic potential in recent in vitro and in vivo experimental models, possibly through a mechanism of action similar to that of flavonoids. However, scientific evidence on the efficacy of these phytochemicals in treating diabetes or preventing the onset and progression of its complications in clinical settings is scarce, which delays the translation of animal study evidence to human applications and also limits the knowledge on their modes of actions in diabetes management. This review is aimed to highlight the potential roles of flavonoids and carotenoids in preventing or ameliorating diabetes-related complications based on in vivo study evidence, i.e., an array of preclinical animal studies and human intervention trials. The current general consensus of the underlying mechanisms of action exerted by both groups of phytochemicals is that their anti-inflammatory action is key. However, other potential mechanisms of action are considered. In total, 50 in vivo studies were selected for a review after a comprehensive database search via PubMed and ScienceDirect from January 2002 to August 2022. The key words used for analysis are type-2 diabetes (T2DM), diabetic complications, flavonoids, carotenoids, antioxidant, anti-inflammatory, mechanisms of prevention and amelioration, animal studies and human interventions

    Event-driven Real-time Retrieval in Web Search

    Full text link
    Information retrieval in real-time search presents unique challenges distinct from those encountered in classical web search. These challenges are particularly pronounced due to the rapid change of user search intent, which is influenced by the occurrence and evolution of breaking news events, such as earthquakes, elections, and wars. Previous dense retrieval methods, which primarily focused on static semantic representation, lack the capacity to capture immediate search intent, leading to inferior performance in retrieving the most recent event-related documents in time-sensitive scenarios. To address this issue, this paper expands the query with event information that represents real-time search intent. The Event information is then integrated with the query through a cross-attention mechanism, resulting in a time-context query representation. We further enhance the model's capacity for event representation through multi-task training. Since publicly available datasets such as MS-MARCO do not contain any event information on the query side and have few time-sensitive queries, we design an automatic data collection and annotation pipeline to address this issue, which includes ModelZoo-based Coarse Annotation and LLM-driven Fine Annotation processes. In addition, we share the training tricks such as two-stage training and hard negative sampling. Finally, we conduct a set of offline experiments on a million-scale production dataset to evaluate our approach and deploy an A/B testing in a real online system to verify the performance. Extensive experimental results demonstrate that our proposed approach significantly outperforms existing state-of-the-art baseline methods

    Effect of Acute Consumption of Blackcurrant Juice on Plasma and Urine Concentrations of Phenolic Acids and Flavonoids and on Antioxidant Status in Human Subjects

    Get PDF
    Epidemiological evidence suggests that consumption of fruits and vegetables rich in flavonoids is inversely linked to the risk of CVD, but the exact mechanisms are unclear. The present study investigated the effects of acute consumption of a 20% blackcurrant juice drink on plasma and urine concentrations of anthocyanin metabolites and plasma antioxidant status in humans. In a randomized, double-blind, placebo-controlled cross-over design, 20 healthy human subjects (ages 30-70 y, 11 females 9 males) consumed 250 mL of the 20% blackcurrant juice drink or a placebo drink on two intervention visits with one-month washout. Blood and urine samples were collected at baseline and periodically after juice intake for 8 hours, in addition to a 24-hour urine sample. Plasma vitamin C concentrations increased significantly from baseline after blackcurrant juice consumption compared to those of the control group throughout the study day (P = 0.001), particularly at 60 – 90 minutes after consumption. The plasma concentrations of phenolic acids that are known metabolites of flavonoids, namely benzoic acid, hippuric acid, salicylic acid and phenylacetic acid tended to increase at 30 and 180 minutes after blackcurrant juice intake, and a weak interaction was observed between juice treatment and time (P = 0.099). The urinary hippuric acid and total phenolics also tended to show non-significant increases after juice consumption. Delphinidin and cyanidin derivatives were not detected in urine samples at quantifiable concentrations, although there was some evidence of traces present in some samples. There were no significant treatment effects on the oxidative stability of plasma assessed by the Oxygen Radical Absorbance Capacity (ORAC) and Ferric Reducing Antioxidant Power (FRAP) values. Plasma uric acid concentration was significantly correlated with the FRAP value of plasma at 0 - 480 minutes after drink consumption (P = 0.000), which is consistent with the important contribution of uric acid to antioxidant capacity. Overall, the effects of the 20% blackcurrant juice drink on plasma concentrations of flavonoid metabolites and plasma antioxidant status did not reach statistical significance

    A Qualitative Exploration on Perceived Socio-Cultural Factors Contributing to Undernutrition Among Under-Fives in the Southern Highlands of Tanzania

    Get PDF
    open access articleObjective: Under nutrition especially among under-fives is a major public health challenge in Tanzania. However, the contribution of cultural practices to child under nutrition is often overlooked. This study aimed to explore the perceived socio-cultural factors contributing to the persisting under nutrition among under-fives in Tanzania. Methods: The study applied focus group discussion (FDGs) with forty practitioners to examine the sociocultural factors contributing to under nutrition during early childhood. The study participants were purposively selected and thematic analysis was used to identify themes within the data. Results: This study revealed that, under nutrition for under-fives is caused by a number of socio-cultural factors including existence of gender inequality related to dietary practices and qualities, women’s excessive workload, patriarchy social-norm, excessive alcohol use and cultural taboos prohibiting women and girls from eating certain types of nutrient dense foods. Conclusion: The study highlights the multiplicity of factors including socio-cultural perspectives contributing to under nutrition among under-fives, and calls for a concerted efforts in developing and implementing issue-specific and culturally sensitive strategies towards elimination of child under nutrition

    Multi-scenario pear tree inflorescence detection based on improved YOLOv7 object detection algorithm

    Get PDF
    Efficient and precise thinning during the orchard blossom period is a crucial factor in enhancing both fruit yield and quality. The accurate recognition of inflorescence is the cornerstone of intelligent blossom equipment. To advance the process of intelligent blossom thinning, this paper addresses the issue of suboptimal performance of current inflorescence recognition algorithms in detecting dense inflorescence at a long distance. It introduces an inflorescence recognition algorithm, YOLOv7-E, based on the YOLOv7 neural network model. YOLOv7 incorporates an efficient multi-scale attention mechanism (EMA) to enable cross-channel feature interaction through parallel processing strategies, thereby maximizing the retention of pixel-level features and positional information on the feature maps. Additionally, the SPPCSPC module is optimized to preserve target area features as much as possible under different receptive fields, and the Soft-NMS algorithm is employed to reduce the likelihood of missing detections in overlapping regions. The model is trained on a diverse dataset collected from real-world field settings. Upon validation, the improved YOLOv7-E object detection algorithm achieves an average precision and recall of 91.4% and 89.8%, respectively, in inflorescence detection under various time periods, distances, and weather conditions. The detection time for a single image is 80.9 ms, and the model size is 37.6 Mb. In comparison to the original YOLOv7 algorithm, it boasts a 4.9% increase in detection accuracy and a 5.3% improvement in recall rate, with a mere 1.8% increase in model parameters. The YOLOv7-E object detection algorithm presented in this study enables precise inflorescence detection and localization across an entire tree at varying distances, offering robust technical support for differentiated and precise blossom thinning operations by thinning machinery in the future

    Multistage Strike-Slip Fault in the Narrowest Portion of the Qinling Orogen, Central China: Deformation Mechanism and Tectonic Significance

    Get PDF
    The North Huicheng Basin strike-slip fault system is on the northeastern frontier of the Tibetan Plateau and separates the West and East Qinling differential orogeny. However, the deformation mechanism of this strike-slip fault system and its exact tectonic significance are unclear. Here, we carried out systematic field structural analysis, physical analog modeling, and multiproxy geochronological dating to address these issues. The field structural analysis indicates that the North Huicheng Basin strike-slip fault system was induced from the plate-like movement of the West and East Qinling Orogens, which underwent multiple left-lateral strike-slip faulting and controlled salient and recessed structures. The scaled physical analog experiment results confirm this hypothesis and reveal the primary spatial-temporal deformational kinematic process. Combined with published works, multiproxy geochronological dating (zircon U‒Pb age of 213 Ma, biotite 40Ar/39Ar age of 203 Ma, and apatite fission-track age of 56 Ma) outlines the main thermal history of the hanging wall. Based on the above facts, the integrated research suggests that multistage strike-slip faulting played a significant role in the main tectonic events, that is, late Triassic magmatic emplacement, Jurassic/Cretaceous local pull-apart, and Cenozoic rapid exhumation driven by Tibetan Plateau growth

    Efficacy of modified thoraco-laparoscopic Ivor-Lewis versus traditional thoraco-laparoscopic Ivor-Lewis for esophageal cancer: Propensity score-matched analysis

    Get PDF
    ObjectiveTo compare the clinical results of the modified Ivor-Lewis procedure, which preserves the azygous vein, thoracic duct and surrounding tissues, with the traditional Ivor-Lewis procedure, which removes these tissues, for treating esophageal squamous cell carcinoma, and evaluating whether the azygous vein, thoracic duct and surrounding tissues are required to be removed for the surgery of esophageal cancer.MethodsTo retrospectively analyze the clinical data of patients suffering from esophageal cancer treated by thoracic-laparoscopic Ivor-Lewis procedure admitted to the Department of Thoracic Surgery of Gansu Provincial People’s Hospital from September 2017 to September 2019. According to the surgical method, they were divided into the modified thoracolaparoscopic Ivor-Lewis (modified group) and the traditional thoracolaparoscopic Ivor-Lewis (traditional group). Propensity score matching analysis (PSM) was applied to reduce the selection bias of confounding factors.ResultsA total of 245 patients who suffered from esophageal cancer and underwent thoracic-laparoscopic Ivor-Lewis were enrolled in the study. There were 124 cases in the modified group and 121 cases in the traditional group. The discrepancies in the age and T-stage among patients in the traditional and modified groups were statistically significant. After PSM, the above-mentioned factors became statistically insignificant. There were 86 patients in each group after PSM. Compared with the traditional group, the modified group has shorter operative time (p=0.007), less intraoperative bleeding (p=0.003) and less postoperative 3 days chest drainage(p=0.001), with a statistically significant difference. No significant difference in local recurrence (p=0.721) and distant metastasis (p=0.742) after surgery were found in the two groups, and the difference was not statistically significant. There was also no statistically significant difference in the 3-year postoperative survival rate (44.2% vs. 41.9%, p=0.605) between the modified and traditional groups.ConclusionThe modified Ivor-Lewis procedure, which preserves the azygous vein, thoracic duct, and surrounding tissue, reduces surgical trauma in esophageal cancer, has not increased postoperative recurrent metastases, while achieved the same long-term outcomes as expanded surgery
    • …
    corecore