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Purpose: Patellofemoral arthroplasty (PFA) was shown to be a potentially effective surgical technique for isolated patellofemoral osteoarthritis but varying reports on PFA-related implant failure and complications have rendered the procedure controversial. This study aimed to identify impactful publications, research interests/efforts, and collaborative networks in the field of PFA research. Methods: The study used the Web of Science Core Collection (WOSCC) database, Medline, Springer, BIOSIS Citation Index, and PubMed to retrieve relevant publications on PFA research published between 1950–2022. Statistical tests in R software were used for analysis while VOSviewer, Bibliometrix, and CiteSpace were employed for data visualization. Results: Two hundred forty-one articles were analyzed with the number of published papers increasing over time. Knee was the most frequent journal and Clinical Orthopaedics and Related Research was the most cited journal. Clinical outcomes, such as prosthesis survival, revision, and complications, were researched most frequently as demonstrated by keyword analysis. The United States was the top contributor to cooperative networks, followed by the United Kingdom while Technical University Munich formed close ties among authors. Conclusion: Publications on PFA research have witnessed a notable surge. They primarily came from a limited number of centers and were characterized by low-level evidence. The majority of studies primarily focused on the clinical outcomes of PFA, while revision of PFA and patient satisfaction have emerged as new research areas. [ABSTRACT FROM AUTHOR]

Background: The term 'pandemic paranoia' has been coined to refer to heightened levels of mistrust and suspicion towards other people specifically due to the COVID-19 pandemic. In this study, we examine the international prevalence of pandemic paranoia in the general population and its associated sociodemographic profile. Methods: A representative international sample of general population adults (N = 2510) from five sites (USA N = 535, Germany N = 516, UK N = 512, Australia N = 502 and Hong Kong N = 445) were recruited using stratified quota sampling (for age, sex, educational attainment) and completed the Pandemic Paranoia Scale (PPS). Results: The overall prevalence rate of pandemic paranoia was 19%, and was highest in Australia and lowest in Germany. On the subscales of the PPS, prevalence was 11% for persecutory threat, 29% for paranoid conspiracy and 37% for interpersonal mistrust. Site and general paranoia significantly predicted pandemic paranoia. Sociodemographic variables (lower age, higher population size and income, being male, employed and no migrant status) explained additional variance and significantly improved prediction of pandemic paranoia. Conclusions: Pandemic paranoia was relatively common in a representative sample of the general population across five international sites. Sociodemographic variables explained a small but significant amount of the variance in pandemic paranoia. [ABSTRACT FROM AUTHOR]

Abstract: Long term containment of stored CO2 in deep geological reservoirs will depend on the performance of the caprock to prevent the buoyant CO2 from escaping to shallow drinking water aquifers or the ground surface. Here we report new laboratory experiments on CO2–brine–caprock interactions and a review of the relevant literature. The Eau Claire Formation is the caprock overlying the Mount Simon sandstone formation, one of the target geological CO2 storage reservoirs in the Midwest USA region. Batch experiments of Eau Claire shale dissolution in brine were conducted at 200°C and 300bars to test the extent of fluid-rock reactions. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis indicate minor dissolution of K-feldspar and anhydrite, and precipitation of pore-filling and pore-bridging illite and/or smectite, and siderite in the vicinity of pyrite. We also reviewed relevant reactivity experiments, modeling work, and field observations in the literature in an attempt to help define the framework for future studies on the geochemical systems of the caprock overlain on geological CO2 storage formations. Reactivity of the caprock is generally shown to be low and limited to the vicinity of the CO2–caprock interface, and is related to the original caprock mineralogical and petrophysical properties. Stable isotope studies indicate that CO2 exists in both free phase and dissolved phase within the caprock. Carbonate and feldspar dissolution is reported in most studies, along with clay and secondary carbonate precipitation. Currently, research is mainly focused on the micro-fracture scale geochemistry of the shaly caprock. More attention is required on the potential pore scale reactions that may become significant given the long time scale associated with geological carbon storage. [Copyright &y& Elsevier]

Abstract: Multi-phase reactive flow and transport modeling is an effective tool for monitoring, verification, and accounting of CO2 sequestration in deep geological formations. In the current study, modeling is performed to simulate large scale CO2 injection (a million tons per year for 100 years) into Mt. Simon sandstone, a major candidate saline reservoir in the Midwest of USA. The long term fate of CO2 was simulated by extending the modeling period to 10,000 years. The results indicate that most of the injected CO2 remains within a radius of 3300m lateral distribution. Four major trapping mechanisms and their spatial and temporal variations are evaluated in our simulations: hydrodynamic, solubility, residual, and mineral trapping. A strongly acidified zone (pH 3–5) forms in the areas affected by the injected CO2 (0–3300m), and consequently causes extensive mineral precipitation and dissolution. The predicted long-term fate of CO2 is closely linked to the geochemical reactions conceptualized in the models. In our model, the replenishing upstream water continues to dissolve CO2 long after the injection, which results in total dissolution of hydrodynamically trapped CO2 at the end of 10,000 years. In contrast, most previous models neglected the regional flow after injection and hence artificially limited the extent of geochemical reactions as if in a batch system. Consequently, a supercritical CO2 plume (hydrodynamic trapping) would persist after 10,000 years. The continued supply of acidified water from interaction between replenishing water and CO2 also results in extensive dissolution of feldspars and precipitation of secondary clay minerals, to a much more extent than what predicted in models without including regional flow. However, the prediction of complete dissolution of feldspars in 10,000 years can also result from the artifact that the linear rate laws are used in our model (as well as all previous work), which overestimates the rates of feldspar dissolution near equilibrium. Nevertheless, our simulations indicate the prolonged existence of an acidic brine plume, which suggests long-term risk assessment should transfer from the primary risk of CO2 leakage to secondary risk of acidic plume leakage after all CO2 is dissolved. [Copyright &y& Elsevier]

Abstract: Naturally weathered feldspar surfaces in the Jurassic Navajo Sandstone at Black Mesa, Arizona, was characterized with high-resolution transmission and analytical electron microscope (HRTEM-AEM) and field emission gun scanning electron microscope (FEG-SEM). Here, we report the first HRTEM observation of a 10-nm thick amorphous layer on naturally weathered K-feldspar in currently slightly alkaline groundwater. The amorphous layer is probably deficient in K and enriched in Si. In addition to the amorphous layer, the feldspar surfaces are also partially coated with tightly adhered kaolin platelets. Outside of the kaolin coatings, feldspar grains are covered with a continuous 3–5μm thick layer of authigenic smectite, which also coats quartz and other sediment grains. Authigenic K-feldspar overgrowth and etch pits were also found on feldspar grains. These characteristics of the aged feldspar surfaces accentuate the differences in reactivity between the freshly ground feldspar powders used in laboratory experiments and feldspar grains in natural systems, and may partially contribute to the commonly observed apparent laboratory-field dissolution rate discrepancy. At Black Mesa, feldspars in the Navajo Sandstone are dissolving at ∼105 times slower than laboratory rate at comparable temperature and pH under far from equilibrium condition. The tightly adhered kaolin platelets reduce the feldspar reactive surface area, and the authigenic K-feldspar overgrowth reduces the feldspar reactivity. However, the continuous smectite coating layer does not appear to constitute a diffusion barrier. The exact role of the amorphous layer on feldspar dissolution kinetics depends on the origin of the layer (leached layer versus re-precipitated silica), which is uncertain at present. However, the nanometer thin layer can be detected only with HRTEM, and thus our study raises the possibility of its wide occurrence in geological systems. Rate laws and proposed mechanisms should consider the possibility of this amorphous layer on feldspar surface. [Copyright &y& Elsevier]

Presents a method for evaluating the pH of hydrothermal fluids from analyses of halogen concentrations in hydrous minerals. Theoretical relation between mineral chlorine concentrations and fluid pH; Application of the relation to the studies of Salton Sea geothermal system.

• Front-of-Package (FOP) nutrition labeling has been introduced in the U.S. over the last decade. • A random coefficients logit model is estimated with data from the U.S. ready-to-eat cereal market. • FOP Participation increases consumer valuation while non-participation lowers it. • Participation and spillover effects are positive and stronger for healthier products. • FOP labeling can play a positive role in improving the healthfulness of consumer food choices. Voluntary nutrition labeling, a means of nutrition quality disclosure, was introduced in the U.S. over the last decade by leading food manufacturers, primarily in the form of front-of-package (FOP) labeling. This article examines how consumer responses to FOP labeling via product participation and information spillovers shift consumer demand across competing products. Applying a random coefficient logit demand model to sales data from the U.S. ready-to-eat cereal market (RTEC) empirically confirms a positive participation effect of FOP and a strong negative spillover effect on non-participating products. Further results indicate that the participation and spillover effects are stronger for healthy RTECs than they are for unhealthy ones. Moreover, ignoring such effects leads to underestimation of consumer valuation of FOP labeling for participating products, higher own-price elasticities of demand and lower price-cost margins. The findings also suggest that an incentive in a firm's voluntary participation in self-regulated labeling programs is to avoid negative treatment externalities and that less health-conscious consumers are not influenced by spillover effects. Overall, this article highlights the importance of including spillover effects in the evaluation of FOP programs and that FOP can play a positive role in improving the healthfulness of consumer choices. [ABSTRACT FROM AUTHOR]

Flight delays in passenger air transportation systems may cause numerous troubles to people's daily life. Empirical works show that at the microscopic level there exist different kinds of inter-correlations, while at the macroscopic level the complex system obeys a simple law similar with that for gases. The constructed theoretical models are not consistent with each other, leading to some debates. How the macroscopic law emerges from the detailed cross-correlations is an open question. And an empirical benchmark to end the debates is also required. In the present work, the cosine correlations between airports for three kinds of flight delays are calculated, the relationships of which versus delay time can be re-scaled by the average number of flights H per month to a universal scaling relation, 〈 C o s θ λ 〉 H p = f λ (〈 T λ 〉 H q) , where p and q are exponents. Hence, the system can work in two kinds of critical phases, namely, the stable phases in the durations from 1995 to 2000 and from 2005 to 2019, and the transition phases in the durations from 2001 to 2004 and within the year 2020. The results provide an empirical benchmark for building models. • American domestic passenger flight records from 1995 to 2020 are downloaded. • Three kinds of cosine correlations and delay time are defined from data. • Scaling relations are obtained by rescaling flight number H per month. • The air transportation systems are confirmed to be in critical states. • Two stable phases and two transition phases are identified. [ABSTRACT FROM AUTHOR]

Flight delays have negative impacts on passengers, carriers, and airports. To reduce these unpopular influence, we need to find the statistical law of the collective behavior of passenger flights. We use a mean-field approach to analyze big data listing the departure and arrival records of all American domestic passenger flights in 20 years. We treat passenger flights as particle gases and define their dimensionless velocity, quasi-thermodynamic quantities — pressure, volume, temperature, and mole number, respectively. By introducing phenomenological parameters a and b to set up van der Waals-like state equations, we erect a universal gaseous constant R for actually operated passenger flights, their counterparts on schedule, and "delayor gases" defined as the difference between them. We find that the attractive coefficient of "delayor gases" positively correlates with the average delay per flight on airports. Rescaling state equations for passenger flights across all 20 years, we find a universal function. This is a significant step toward understanding flight delays and dealing with temporal big data with the tools of statistical physics. • The air transportation is studied with departure/arrival records for 20 years from statistical physics perspective. • The passenger flights are treated as particle gases, and a van der Waals-like state equation is set up. • The universal form of the state equation is found by rescaling those for different years. • A novel virtual particle gas - "delayor gas" is defined to promote the research on flight delays. [ABSTRACT FROM AUTHOR]