In a quantitative model of Social Security with endogenous health, I argue that Social Security increases the aggregate health spending of the economy because it redistributes resources to the ...elderly whose marginal propensity to spend on health is high. I show by using computational experiments that the expansion of US Social Security can account for over a third of the dramatic rise in US health spending from 1950 to 2000. In addition, Social Security has a spill-over effect on Medicare. As Social Security increases health spending, it also increases the payments from Medicare, thus raising its financial burden.
•The impact of Social Security on health spending is evaluated.•Social Security accounts for a fraction of the rise in US health spending.•The negative effect of Social Security on capital accumulation is studied.•Social Security has a spill-over effect on Medicare's financial burden.
With set point regulation being the most common goal in control engineering, persistence of excitation (PE) is generically absent in adaptive control applications. In the absence of PE, not only is ...the parameter estimate not guaranteed to converge to the true value, but the state is regulated to the set point at a rate that is not necessarily exponential. In this technical note we introduce a strategy that employs time-varying adaptation gains (as well as time-varying control gains, when appropriate) and achieves exponential regulation of the plant state, with an exponential rate that is uniform in the initial condition. This idea fundamentally differs from exponential stability results achieved in the presence of PE because we make the gains (rather than reference signals) time-varying, i.e., we use time-varying tools in a multiplicative (rather than in an additive) fashion. We provide full state feedback results for general classes of nonlinear and linear systems and establish global uniform stability, exponential regulation of the plant state, boundedness of the control input and the update rate, and the asymptotic constancy (but not convergence to the true value) of the parameter estimate.
By taking the spatial interdependence into account, this paper studies both the competitive effects of international trade and the technology spillover effects on R&D innovation. First, the ...Schumpeterian model of endogenous growth has been theoretically expanded; then, this paper incorporates the “spatial interdependence” of countries into the research framework by a structured approach; furthermore, using the data of 69 countries from 2000 to 2015, the theoretical results are tested by empirical analysis. It is found that the more advanced a country is, the less it will benefit from the technological spillover from neighboring countries; developing countries ought to gain the benefits of technological externalities through increasing trade openness and international competition.
Display omitted
•LovPSA is a type I photosensitizer with the highest O2• − quantum yield, which can efficiently and selectively produce O2• −.•LovPSO is a type II photosensitizer with the highest 1O2 ...quantum yield, which can efficiently and selectively produce 1O2.•LovPRO can generate both superoxide anion O2• − and 1O2.•LovPRO, LovPSO, and LovPSA produce ROS and mediate significant cytotoxicity under light irradiation.
Reactive oxygen species (ROS), such as superoxide anion (O2• −) and singlet oxygen (1O2), play important roles in the process of intracellular oxidative stress. Limitations in studies on the intracellular behavior and mechanisms of ROS are generally related to the difficulty in controlling the species, location, and amount of ROS produced within the cell. Therefore, it is necessary to develop genetically encoded photosensitizers that can efficiently and selectively generate O2• − and/or 1O2. We report the genetic encoding photosensitizer LovPSA, a flavoprotein engineered from Oryza sativa japonica phototropin 2 that efficiently generates O2• −. By rationally designing LovPSA to reduce the O2• − produced by charge transfer, we developed the photosensitizer LovPSO, which can efficiently and selectively generate 1O2, and LovPRO, a photosensitizer that can produce both O2• − and 1O2. LovPSO has a unique 1O2 quantum yield (ΦΔ = 0.68). We confirmed that LovPSA, LovPSO, and LovPRO have good thermostability and photostability. In addition, they also exhibit excellent phototoxicity. These results contribute to our current understanding of the interactions between the light-oxygen-voltage (LOV) apo-protein and the chromophore FMN and provide new tools for the study of intracellular ROS mechanisms and photodynamic therapy (PDT).
An accurate State-of-Charge (SoC) estimation plays a significant role in battery systems used in electric vehicles due to the arduous operation environments and the requirement of ensuring safe and ...reliable operations of batteries. Among the conventional methods to estimate SoC, the Coulomb counting method is widely used, but its accuracy is limited due to the accumulated error. Another commonly used method is model-based online iterative estimation with the Kalman filters, which improves the estimation accuracy in some extent. To improve the performance of Kalman filters in SoC estimation, the adaptive extended Kalman filter (AEKF), which employs the covariance matching approach, is applied in this paper. First, we built an implementation flowchart of the AEKF for a general system. Second, we built an online open-circuit voltage (OCV) estimation approach with the AEKF algorithm so that we can then get the SoC estimate by looking up the OCV-SoC table. Third, we proposed a robust online model-based SoC estimation approach with the AEKF algorithm. Finally, an evaluation on the SoC estimation approaches is performed by the experiment approach from the aspects of SoC estimation accuracy and robustness. The results indicate that the proposed online SoC estimation with the AEKF algorithm performs optimally, and for different error initial values, the maximum SoC estimation error is less than 2% with close-loop state estimation characteristics.
Chitosan is a biodegradable natural polymer with many advantages such as nontoxicity, biocompatibility, and biodegradability. It can be applied in many fields, especially in medicine. As a delivery ...carrier, it has great potential and cannot be compared with other polymers. Chitosan is extremely difficult to solubilize in water, but it can be solubilized in acidic solution. Its insolubility in water is a major limitation for its use in medical applications. Chitosan derivatives can be obtained by chemical modification using such techniques as acylation, alkylation, sulfation, hydroxylation, quaternization, esterification, graft copolymerization, and etherification. Modified chitosan has chemical properties superior to unmodified chitosan. For example, nanoparticles produced from chitosan derivatives can be used to deliver drugs due to their stability and biocompatibility. This review mainly focuses on the properties of chitosan, chitosan derivatives, and the origin of chitosan-based nanoparticles. In addition, applications of chitosan-based nanoparticles in drug delivery, vaccine delivery, antimicrobial applications, and callus and tissue regeneration are also presented. In summary, nanoparticles based on chitosan have great potential for research and development of new nano vaccines and nano drugs in the future.
The mobility of economic factors across jurisdictions has led to increased fiscal competition among decentralized subnational governments. This study examines the relationship between fiscal ...competition and long-term investment in innovation at the local government level. Panel data analysis, encompassing expenditures, taxes, and innovation inputs from 18 municipalities over a 10-year period, is employed using fixed effects regression. The results reveal a negative correlation between fiscal competition and expenditure on innovation, indicating that intensified competition for mobile capital diverts resources away from essential long-term investments crucial for knowledge-driven growth. Even after controlling for economic and institutional factors, a one standard deviation increase in competition corresponds to an average decline of 25% in per capita innovation investment. These findings highlight the unintended trade-off resulting from heightened competition and underscore the need for policy frameworks that promote localized flexibility while curbing uncoordinated competition that undermines innovation capacity. While fiscal decentralization aims to foster competitive governance, this study provides empirical evidence that short-term expenditure incentives often displace long-term innovation objectives without sufficient coordination. The insights contribute significant empirical evidence on the concealed costs of fiscal competition for regional development. Consequently, a re-evaluation of conventional perspectives on decentralization and competition is warranted, emphasizing the importance of developing cooperative policy solutions that strike a delicate balance between decentralized decision autonomy and strategic coordination. Adopting such an approach is essential to fully leverage the advantages of competitive governance while simultaneously nurturing innovation ecosystems.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
9.
Assembly of CpcL‐phycobilisomes Guo, Rui; Xu, Ya‐Li; Zhu, Jun‐Xun ...
The Plant journal : for cell and molecular biology,
20/May , Letnik:
118, Številka:
4
Journal Article
Recenzirano
SUMMARY
CpcL‐phycobilisomes (CpcL‐PBSs) are a reduced type of phycobilisome (PBS) found in several cyanobacteria. They lack the traditional PBS terminal energy emitters, but still show the ...characteristic red‐shifted fluorescence at ~670 nm. We established a method of assembling in vitro a rod‐membrane linker protein, CpcL, with phycocyanin, generating complexes with the red‐shifted spectral features of CpcL‐PBSs. The red‐shift arises from the interaction of a conserved key glutamine, Q57 of CpcL in Synechocystis sp. PCC 6803, with a single phycocyanobilin chromophore of trimeric phycocyanin at one of the three β82‐sites. This chromophore is the terminal energy acceptor of CpcL‐PBSs and donor to the photosystem(s). This mechanism also operates in PBSs from Acaryochloris marina MBIC11017. We then generated multichromic complexes harvesting light over nearly the complete visible range via the replacement of phycocyanobilin chromophores at sites α84 and β153 of phycocyanins by phycoerythrobilin and/or phycourobilin. The results demonstrate the rational design of biliprotein‐based light‐harvesting elements by engineering CpcL and phycocyanins, which broadens the light‐harvesting range and accordingly improves the light‐harvesting capacity and may be potentially applied in solar energy harvesting.
Significance Statement
Cyanobacteria have a rod‐shaped CpcL‐phycobilisome (CpcL‐PBS) possessing a red‐shifted fluorescence at 670 nm. We establish a method of assembling CpcL‐PBSs in vitro, accordingly, showing the mechanism of the red‐shifted fluorescence optimizing energy transfer of CpcL‐PBSs. It is pinpointed to the interaction of a single chromophore in phycocyanins with a key glutamine of CpcL. Complexes of different sizes are engineered using tagged CpcL as an assembly template, including complexes with modified chromophores.
Bat Coronaviruses in China Fan, Yi; Zhao, Kai; Shi, Zheng-Li ...
Viruses,
03/2019, Letnik:
11, Številka:
3
Journal Article
Recenzirano
Odprti dostop
During the past two decades, three zoonotic coronaviruses have been identified as the cause of large-scale disease outbreaks⁻Severe Acute Respiratory Syndrome (SARS), Middle East Respiratory Syndrome ...(MERS), and Swine Acute Diarrhea Syndrome (SADS). SARS and MERS emerged in 2003 and 2012, respectively, and caused a worldwide pandemic that claimed thousands of human lives, while SADS struck the swine industry in 2017. They have common characteristics, such as they are all highly pathogenic to humans or livestock, their agents originated from bats, and two of them originated in China. Thus, it is highly likely that future SARS- or MERS-like coronavirus outbreaks will originate from bats, and there is an increased probability that this will occur in China. Therefore, the investigation of bat coronaviruses becomes an urgent issue for the detection of early warning signs, which in turn minimizes the impact of such future outbreaks in China. The purpose of the review is to summarize the current knowledge on viral diversity, reservoir hosts, and the geographical distributions of bat coronaviruses in China, and eventually we aim to predict virus hotspots and their cross-species transmission potential.
PDF
