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Artificial intelligence (AI) is reshaping the online shopping experience. However, there is limited information on consumers' interaction with AI elements embedded in electronic commerce (e-commerce) platforms and the behavioral outcomes of such interactions. AI application studies have focused on consumers' reluctance to use AIpowered services due to failed machine-human conversations. On the contrary, this study exploits the bright side of AI applications in e-commerce. It applies the stimuli-organism-response (S-O-R) paradigm to examine the effects of AI elements on consumer engagement attitudes, beyond purchase intentions, towards e-commerce platforms. Specifically, it examined the impact of chatbot efficiency, image search functionality, recommendation system efficiency, and automated after-sales service on consumer engagement. Furthermore, the study examined the moderating role of consumers' attention to the social comparison of consumption choices on the relationships between the AI capability elements and consumer engagement. The partial least square-structural equation modeling (PLS-SEM) approach was employed in analyzing 464 responses collected via an online survey from consumers of different e-commerce platforms. The findings indicate that AI capability elements, directly and indirectly, attract consumers' observable engagement behaviors. Also, attention to social comparison dampens the positive effects of chatbot efficiency and automated after-sales service on behavioral engagement. In contrast, it positively moderates the impact of recommendation system efficiency. The study contributes to academia by introducing consumers' attention to social comparison to advance the understanding of consumer engagement with AI applications in ecommerce. Practitioners can gain insight into improving consumer experience on e-commerce platforms. [ABSTRACT FROM AUTHOR]

According to reservoir damage problems in Lower Paleozoic of Jingnan Block, the geological and physical characteristics of target reservoirs were analyzed. Then potential reservoir damage factors and damage mechanism were studied through comprehensive sensitivity experiments and water lock test. The results show that the target reservoir has strong water sensitivity damage, water-lock effect and pressure sensitivity damage. Based on fractured reservoir damage mechanism analysis, temporary blocking countermeasures were carried out. In addition, environmentally spherical particles and fibrous temporary plugging materials (QXZ andXWZ) were optimized and combined to achieve ideal temporary plugging effect. Considering complicated drilling case in target block, novel reservoir protection drilling fluid HPW was established. It exhibits good rheological properties, lubricating performance and filter loss properties. Furthermore, preferable inhibition and reservoir protection performance can be achieved. On this basis, the field trial results show that density, rheological properties, loss properties and lubricating performance of HPW have a greater improvement. And the drilling cycle and operation cost have been greatly shortened. [ABSTRACT FROM AUTHOR]

With the increasing difficulty of oil and gas exploration, the complex wells such as extended reach wells, horizontal wells and ultra-deep wells are used frequently. And water-based drilling fluids are still the main choice for the above complex wells. Therefore, friction and drag reduction of water-based drilling fluid lubricants are particularly important. With the increasingly stringent requirements of environmental protection, the environmental protection performance of drilling fluids has attracted much attention. But drilling fluid lubricants commonly used in the field are usually mineral oil, vegetable oil, which are easily to cause environment pollution, and have been gradually abandoned. Using biodiesel and polyether amine as the main raw materials, a novel drilling fluid lubricant HPR-1 was developed by series amidation reactions. Then the conventional physicochemical properties, lubricating properties, environmental proper - ties and compatibility with drilling fluids were evaluated. The results show that the conventional properties of lubricant HPR-1 can meet the basic requirements for drilling fluid lubricants. And the coefficient of friction of bentonite base mud can be reduced by 90.25% with 0.5wt% HPR-1 addition. The fluorescence level of HPR-1 was only 1~2 level, and the biotoxicity determination and biodegradability evaluation exhibited non-toxic and biodegradable. Furthermore, the addition of HPR-1 has slight effect on the main properties of drilling fluid with good compatibility. And the lubricating mechanism of HPR-1 was discussed. [ABSTRACT FROM AUTHOR]

It is a challenging issue to improve the energy efficiency of neighbor discovery in WSNs. This paper proposes an optimal discovery model (ODM) for the first time. Based on the model, we investigate the influence of the relative size of two unequal active slots on the energy efficiency. ODM provides the energy optimal value of the length of the larger active slot at a given duty cycle. Other than existing methods, the worst-case latency bound of ODM is only one period. This is a subversive conclusion, because almost all other related methods are based on a wake-up schedule that contains several periods. We theoretically deduce that ODM can reduce worst-case discovery latency by 43.89% compared to Searchlight-Trim when their duty cycles are the same. The simulations verify the advantage of ODM [ABSTRACT FROM AUTHOR]

Fracturing-fluid invasion into the rock matrix can generate water block that potentially reduces hydrocarbon production, especially in low-permeability reservoirs. Here, we experimentally investigate the dynamics of water block under different flow scenarios (i.e., without shut-ins) and rock permeabilities through multiple coreflood experiments. A computed-tomography (CT) scanner is used to obtain the saturation profile within the core throughout the experiment, while the overall hydrocarbon productivity is measured from the overall pressure drop across the core. On the basis of the saturation and pressure measurements, we interpret the potential physical mechanism regarding the productivity reduction from water block and its self-mitigation facilitated by the capillary imbibition. Our interpretation also matches the observed scaling with rock permeability and the optimal shut-in time. [ABSTRACT FROM AUTHOR]

IMPORTANCE A relapse into nicotine addiction during abstinence often occurs after the reactivation of nicotine reward memories, either by acute exposure to nicotine (a smoking episode) or by smoking-associated conditioned stimuli (CS). Preclinical studies suggest that drug reward memories can undergo memory reconsolidation after being reactivated, during which they can be weakened or erased by pharmacological or behavioral manipulations. However, translational clinical studies using CS-induced memory retrieval-reconsolidation procedures to decrease drug craving reported inconsistent results. OBJECTIVE To develop and test an unconditioned stimulus (UCS)-induced retrievalreconsolidation procedure to decrease nicotine craving among people who smoke. DESIGN, SETTING, AND PARTICIPANTS A translational rat study and human study in an academic outpatient medical center among 96 male smokers (aged 18-45 years) to determine the association of propranolol administration within the time windowof memory reconsolidation (after retrieval of the nicotine-associated memories by nicotine UCS exposure) with relapse to nicotine-conditioned place preference (CPP) and operant nicotine seeking in rats, and measures of preference to nicotine-associated CS and nicotine craving among people who smoke. INTERVENTION The study rats were injected noncontingently with the UCS (nicotine 0.15mg/kg, subcutaneous) in their home cage, and the human study participants administered a dose of propranolol (40mg, per os; Zhongnuo Pharma). MAIN OUTCOMES AND MEASURES Nicotine CPP and operant nicotine seeking in rats, and preference and craving ratings for newly learned and preexisting real-life nicotine-associated CS among people who smoke. RESULTS Sixty-nine male smokers completed the experiment andwere included for statistical analysis: 24 in the group that received placebo plus 1 hour plus UCS, 23 who received propranolol plus 1 hour plus UCS, and 22 who received UCS plus 6 hours plus propranolol. In rat relapse models, propranolol injections administered immediately after nicotine UCS-induced memory retrieval inhibited subsequent nicotine CPP and operant nicotine seeking after short (CPP, d = 1.72, 95%CI, 0.63-2.77; operant seeking, d = 1.61, 95%CI, 0.59-2.60) or prolonged abstinence (CPP, d = 1.46, 95%CI, 0.42-2.47; operant seeking: d = 1.69, 95%CI, 0.66-2.69), as well as nicotine priming-induced reinstatement of nicotine CPP (d = 1.28, 95%CI, 0.27-2.26) and operant nicotine seeking (d = 1.61, 95%CI, 0.59-2.60) after extinction. Among the smokers, oral propranolol administered prior to nicotine UCS-induced memory retrieval decreased subsequent nicotine preference induced by newly learned nicotine CS (CS1, Cohen d=0.61, 95%CI, 0.02-1.19 and CS2, d = 0.69, 95%CI, 0.10-1.28, respectively), preexisting nicotine CS (d = 0.57, 95%CI, -0.02 to 1.15), and nicotine priming (CS1, d = 0.82, 95%CI, 0.22-1.41 and CS2, d = 0.78, 95%CI, 0.18-1.37, respectively; preexisting nicotine CS, d = 0.92, 95%CI, 0.31-1.52), aswell as nicotine craving induced by the preexisting nicotine CS (d = 0.64, 95%CI, 0.05-1.22), and nicotine priming (d = 1.15, 95%CI, 0.52-1.76). CONCLUSIONS AND RELEVANCE In rat-to-human translational study, a novel UCS-induced memory retrieval-reconsolidation interference procedure inhibited nicotine craving induced by exposure to diverse nicotine-associated CS and nicotine itself. This procedure should be studied further in clinical trials. [ABSTRACT FROM AUTHOR]

Designing a theory-based assessment with sound psychometric qualities to measure a higher-order cognitive construct is a highly desired yet challenging task for many practitioners. This paper proposes a framework for designing a theory- based assessment to measure a higher-order cognitive construct. This framework results in a modularized yet unified assessment development system which includes elements spanning from construct conceptualization to model validation. The paper illustrates how to implement this framework by using the construct of nursing clinical judgment. Using this framework, many difficult design decisions can be made with strong theoretical rationales. The framework is also flexible to accommodate modifications and extensions that will be required to be made to the assessment as new knowledge related to the construct is generated over time. The goal of this framework is to provide practitioners with a practical and accessible methodology to assess sophisticated constructs on the ground of cognitive theories of the construct, especially by using technology enhanced items. [ABSTRACT FROM AUTHOR]

In practice, there is a growing need of reporting both overall score for the ranking/decision-making purpose and subscores for the diagnostic purpose. The Rasch model with subdimensions (RMS) was employed in this study to address this problem. Ajoint maximum likelihood estimation (JMLE) procedure was proposed to obtain computationally efficient estimation for this model. A simulation study was conducted to investigate the properties of this model with the JMLE procedure in conditions with varying sample size, test lengths and subdimension loading structure. Results indicated that in general, parameters were estimated well using the JMLE procedure. The item parameters and overall ability parameters in RMS were in accordance with parameters obtained from the Rasch model. [ABSTRACT FROM AUTHOR]

The forms of nitrogen in experimental blended coal/char and combustion characteristics as well as char-nitrogen conversion rules of the char in air atmosphere were investigated by the ways of X-ray photoelectron spectroscopy (XPS) and thermogravimetry-fourier transform infrared spectroscopy (TG-FTIR). The results show that the pyrrolic nitrogen (N-5) in char is relative instability after high-temperature pyrolysis by comparing main occurrence modes of nitrogen between the experimental blended coal and the corresponding char. The TG curve of experimental char gradually falls in the range of 460~756 °C and the DTG curve reaches the peak at 666 °C. The activation energy of the char combustion is 93.9 KJ/mol in the range of the same temperature above based on the method of Coats-Red fern. The main gases include CO2, CO, NO, NO2, N2O, HNCO and HCN. [ABSTRACT FROM AUTHOR]

Background: Human growth is susceptible to damage from insults, particularly during periods of rapid growth. Identifying those periods and the normative limits that are compatible with adequate growth and development are the first key steps toward preventing impaired growth.Objective: This study aimed to construct international fetal growth velocity increment and conditional velocity standards from 14 to 40 weeks' gestation based on the same cohort that contributed to the INTERGROWTH-21st Fetal Growth Standards.Study Design: This study was a prospective, longitudinal study of 4321 low-risk pregnancies from 8 geographically diverse populations in the INTERGROWTH-21st Project with rigorous standardization of all study procedures, equipment, and measurements that were performed by trained ultrasonographers. Gestational age was accurately determined clinically and confirmed by ultrasound measurement of crown-rump length at <14 weeks' gestation. Thereafter, the ultrasonographers, who were masked to the values, measured the fetal head circumference, biparietal diameter, occipitofrontal diameter, abdominal circumference, and femur length in triplicate every 5 weeks (within 1 week either side) using identical ultrasound equipment at each site (4-7 scans per pregnancy). Velocity increments across a range of intervals between measures were modeled using fractional polynomial regression.Results: Peak velocity was observed at a similar gestational age: 16 and 17 weeks' gestation for head circumference (12.2 mm/wk), and 16 weeks' gestation for abdominal circumference (11.8 mm/wk) and femur length (3.2 mm/wk). However, velocity growth slowed down rapidly for head circumference, biparietal diameter, occipitofrontal diameter, and femur length, with an almost linear reduction toward term that was more marked for femur length. Conversely, abdominal circumference velocity remained relatively steady throughout pregnancy. The change in velocity with gestational age was more evident for head circumference, biparietal diameter, occipitofrontal diameter, and femur length than for abdominal circumference when the change was expressed as a percentage of fetal size at 40 weeks' gestation. We have also shown how to obtain accurate conditional fetal velocity based on our previous methodological work.Conclusion: The fetal skeleton and abdomen have different velocity growth patterns during intrauterine life. Accordingly, we have produced international Fetal Growth Velocity Increment Standards to complement the INTERGROWTH-21st Fetal Growth Standards so as to monitor fetal well-being comprehensively worldwide. Fetal growth velocity curves may be valuable if one wants to study the pathophysiology of fetal growth. We provide an application that can be used easily in clinical practice to evaluate changes in fetal size as conditional velocity for a more refined assessment of fetal growth than is possible at present (https://lxiao5.shinyapps.io/fetal_growth/). The application is freely available with the other INTERGROWTH-21st tools at https://intergrowth21.tghn.org/standards-tools/. [ABSTRACT FROM AUTHOR]