With the promotion of Industry 4.0, which emphasizes interconnected and intelligent devices, several factories have introduced numerous terminal Internet of Things (IoT) devices to collect relevant ...data or monitor the health status of equipment. The collected data are transmitted back to the backend server through network transmission by the terminal IoT devices. However, as devices communicate with each other over a network, the entire transmission environment faces significant security issues. When an attacker connects to a factory network, they can easily steal the transmitted data and tamper with them or send false data to the backend server, causing abnormal data in the entire environment. This study focuses on investigating how to ensure that data transmission in a factory environment originates from legitimate devices and that related confidential data are encrypted and packaged. This paper proposes an authentication mechanism between terminal IoT devices and backend servers based on elliptic curve cryptography and trusted tokens with packet encryption using the TLS protocol. Before communication between terminal IoT devices and backend servers can occur, the authentication mechanism proposed in this paper must first be implemented to confirm the identity of the devices and, thus, the problem of attackers imitating terminal IoT devices transmitting false data is resolved. The packets communicated between devices are also encrypted, preventing attackers from knowing their content even if they steal the packets. The authentication mechanism proposed in this paper ensures the source and correctness of the data. In terms of security analysis, the proposed mechanism in this paper effectively withstands replay attacks, eavesdropping attacks, man-in-the-middle attacks, and simulated attacks. Additionally, the mechanism supports mutual authentication and forward secrecy. In the experimental results, the proposed mechanism demonstrates approximately 73% improvement in efficiency through the lightweight characteristics of elliptic curve cryptography. Moreover, in the analysis of time complexity, the proposed mechanism exhibits significant effectiveness.
Over the past few decades, stimuli‐responsive materials have been widely applied to porous surfaces. Permeability and conductivity control of ions confined in nanochannels modified with ...stimuli‐responsive materials, however, have been less investigated. In this work, the permeability and conductivity control of ions confined in nanochannels of anodic aluminum oxide (AAO) templates modified with thermo‐responsive poly(N‐isopropylacrylamide) (PNIPAM) brushes are demonstrated. By surface‐initiated atom transfer radical polymerization (SI‐ATRP), PNIPAM brushes are successfully grafted onto the hexagonally packed cylindrical nanopores of AAO templates. The surface hydrophilicities of the membranes can be reversibly altered because of the lower critical solution temperature (LCST) behavior of the PNIPAM polymer brushes. From electrochemical impedance spectroscopy (EIS) analysis, the temperature‐gating behaviors of the AAO‐g‐PNIPAM membranes exhibit larger impedance changes than those of the pure AAO membranes at higher temperatures because of the aggregation of the grafted PNIPAM chains. The reversible surface properties caused by the extended and collapsed states of the polymer chains are also demonstrated by dye release tests. The smart thermo‐gated and ion‐controlled nanoporous membranes are suitable for future smart membrane applications.
Progress in solid‐state nanochannels development: A thermo‐responsive polymer poly(N‐isopropylacrylamide) (PNIPAM) brushes grafted anodic aluminum oxide (AAO) membrane by surface‐initiated atom transfer radical polymerization (SI‐ATRP) is presented. This thermo‐gated smart membrane shows a reversible surface wettability change, which allows the smart membrane to control the ion conductivity and ensures the dye release ability.
Stimuli-responsive ion nanochannels have attracted considerable attention in various fields because of their remote controllability of ionic transportation. For photoresponsive ion nanochannels, ...however, achieving precise regulation of ion conductivity is still challenging, primarily due to the difficulty of programmable structural changes in confined environments. Moreover, the relationship between noncontact photo-stimulation in nanoscale and light-induced ion conductivity has not been well understood. In this work, a versatile design for fabricating guard cell-inspired photoswitchable ion channels is presented by infiltrating azobenzene-cross-linked polymer (AAZO-PDAC) into nanoporous anodic aluminum oxide (AAO) membranes. The azobenzene-cross-linked polymer is formed by azobenzene chromophore (AAZO)-cross-linked poly(diallyldimethylammonium chloride) (PDAC) with electrostatic interactions. Under UV irradiation, the trans-AAZO isomerizes to the cis-AAZO, causing the volume compression of the polymer network, whereas, in darkness, the cis-AAZO reverts to the trans-AAZO, leading to the recovery of the structure. Consequently, the resultant nanopore sizes can be manipulated by the photomechanical effect of the AAZO-PDAC polymers. By adding ionic liquids, the ion conductivity of the light-driven ion nanochannels can be controlled with good repeatability and fast responses (within seconds) in multiple cycles. The ion channels have promising potential in the applications of biomimetic materials, sensors, and biomedical sciences.
European Union public healthcare expenditure on treating smoking and attributable diseases is estimated at over €25bn annually. The reduction of tobacco consumption has thus become one of the major ...social policies of the EU. This study investigates the effects of price hikes on cigarette consumption, tobacco tax revenues and smoking-caused deaths in 28 EU countries.
Employing panel data for the years 2005 to 2014 from Euromonitor International, the World Bank and the World Health Organization, we used income as a threshold variable and applied threshold regression modelling to estimate the elasticity of cigarette prices and to simulate the effect of price fluctuations.
The results showed that there was an income threshold effect on cigarette prices in the 28 EU countries that had a gross national income (GNI) per capita lower than US$5418, with a maximum cigarette price elasticity of -1.227. The results of the simulated analysis showed that a rise of 10% in cigarette price would significantly reduce cigarette consumption as well the total death toll caused by smoking in all the observed countries, but would be most effective in Bulgaria and Romania, followed by Latvia and Poland. Additionally, an increase in the number of MPOWER tobacco control policies at the highest level of achievment would help reduce cigarette consumption.
It is recommended that all EU countries levy higher tobacco taxes to increase cigarette prices, and thus in effect reduce cigarette consumption. The subsequent increase in tobacco tax revenues would be instrumental in covering expenditures related to tobacco prevention and control programs.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Untethered small actuators have drawn tremendous interest owing to their reversibility, flexibility, and widespread applications in various fields. For polymer actuators, however, it is still ...challenging to achieve programmable structural changes under different stimuli caused by the intractability and single‐stimulus responses of most polymer materials. Herein, multi‐stimuli‐responsive polymer actuators that can respond to light and solvent via structural changes are developed. The actuators are based on bilayer films of polydimethylsiloxane (PDMS) and azobenzene chromophore (AAZO)‐crosslinked poly(diallyldimethylammonium chloride) (PDAC). Upon UV light irradiation, the AAZO undergoes trans‐cis‐trans photoisomerization, causing the bending of the bilayer films. When the UV light is off, a shape recovery toward an opposite direction occurs spontaneously. The reversible deformation can be repeated at least 20 cycles. Upon solvent vapor annealing, one of the bilayer films can be selectively swollen, causing the bending of the bilayer films with the directions controlled by the solvent vapors. The effects of different parameters, such as the weight ratios of AAZO and film thicknesses, on the bending angles and curvatures of the polymer films are also analyzed. The results demonstrate that multi‐stimuli‐responsive actuators with fast responses and high reproducibility can be fulfilled.
Multi‐stimuli‐responsive polymer actuators that can respond to light and solvent via structural changes with fast responses and high reproducibility are developed. The actuators are based on bilayer films of polydimethylsiloxane and azobenzene chromophore‐crosslinked poly(diallyldimethylammonium chloride). The effects of different parameters on the bending angles and curvatures of the polymer films are also analyzed.
According to the World Health Organization (WHO), 80% of the world's smokers live in low- and middle-income countries. Moreover, more than half of the world's smoking-addicted population resides in ...the Asia-Pacific region. The reduction of tobacco consumption has thus become one of the major social policies in the region. This study investigates the effects of price increases on cigarette consumption, tobacco tax revenues and reduction in smoking-caused mortality in 22 low-income as well as middle-income countries in the Asia-Pacific region.
Using panel data from the 1999-2015 Euromonitor International, the World Bank and the World Health Organization, we applied fixed effects regression models of panel data to estimate the elasticity of cigarette prices and to simulate the effect of price fluctuations.
Cigarette price elasticity was the highest for countries with a per capita Gross National Income (GNI) above US$6000 (China and Malaysia), and considerably higher for other economies in the region. The administered simulation shows that with an average annual cigarette price increase of 9.51%, the average annual cigarette consumption would decrease by 3.56%, and the average annual tobacco tax revenue would increase by 16.20%. The number of averted smoking-attributable deaths (SADs) would be the highest in China, followed by Indonesia and India. In total, over 17.96 million lives could be saved by tax increases.
Excise tax increases have a significant effect on the reduction of smoking prevalence and the number of averted smoking-attributable deaths. Middle- and upper-middle income countries would be most affected by high-taxation policies.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Milkfish, Chanos chanos, is often cultured with white shrimp, Penaeus indicus, to maintain ecological stability and increase profits. This study uses the outputs and cost data of 169 milkfish farmers ...in Taiwan for the years 2018 and 2019 and applies translog cost function modeling to analyze the production scale economy and input–input demand combinations of two stocking densities (<10,000, ≥10,000 fry/ha) and two fry stocking sizes (2–3 in. and ≥4 in.). The study found that high‐density stocking (≥10,000 fry/ha) of small or large milkfish fry has economies of scale overall. Thus, the average culture cost may be reduced by expanding the scale of milkfish production. High‐density stocking of small fry exhibits a comparatively higher own‐price elasticity of fry. As such, farmers are sensitive to fry price variations. The study also found that labor and capital exhibit the highest substitutability. Capital inputs may thus be increased to mitigate the effects of wage increments. In terms of production, the four observed clusters do not exhibit cost complementarity. Moreover, the survival rate of white shrimp in high‐density stocking milkfish polycultures is relatively low. It is thus recommended to strictly control the stocking density of white shrimp and to minimize the risk of excessively high stocking densities by stocking white shrimp in batches.
Stress-induced phosphoprotein-1 (STIP1)-a heat shock protein (HSP)70/HSP90 adaptor protein-is commonly overexpressed in malignant cells, where it controls proliferation via multiple signaling ...pathways, including JAK2/STAT3. We have previously shown that STIP1 stabilizes the protein tyrosine kinase JAK2 in cancer cells via HSP90 binding. In this study, we demonstrate that STIP1 may act as a substrate for JAK2 and that phosphorylation of tyrosine residues 134 and 152 promoted STIP1 protein stability, induced its nuclear-cytoplasmic shuttling, and promoted its secretion into the extracellular space. We also found that JAK2-mediated STIP1 phosphorylation enhanced cell viability and increased resistance to cisplatin-induced cell death. Conversely, interference STIP1 with JAK2 interaction-attained either through site-directed mutagenesis or the use of cell-penetrating peptides-decreased JAK2 protein levels, ultimately leading to cell death. On analyzing human ovarian cancer specimens, JAK2 and STIP1 expression levels were found to be positively correlated with each other. Collectively, these results indicate that JAK2-mediated phosphorylation of STIP-1 is critical for sustaining the JAK2/STAT3 signaling pathway in cancer cells.
Outlying islands are affected by the environment and economy, and fishery resources are the first to experience these impacts. Therefore, it is necessary to actively and effectively transform ...traditional fisheries in outlying islands. This is the case in Penghu County (Penghu Islands), located on the outlying islands of Taiwan. The transformation to recreational fishery can increase the additional income of traditional fisheries during the fishing moratorium through the development of recreational fishery boats by fishermen. Recreational fishery means the fishery using fishing vessels for recreational purposes or for passengers to harvest aquatic organisms on the reef or to engage in sightseeing on the islets. Therefore, this study will explore the key factors for the successful route planning of fishermen who switch to recreational fishery boats to assist the fishermen in successfully transitioning and enabling recreational fishery to flourish. In the research, using the method of the Analytic Hierarchy Process (AHP) expert questionnaire, it was found that the key factors affecting the route planning of recreational fishery boats are “boat conditions”, “berthing conditions”, “operating environment”, and “sightseeing potential”. After the expert questionnaire, a weight comparison of each level was performed, and it was found that “operating environment” was the most important factor, followed by “tourism potential”. However, the key factors of the “natural environment” and “cultural environment” are more important under the influence of the “operating environment”. Under the influence of “tourism potential”, “attractiveness” is a key factor, as is the “accessibility” factor. In this study, the four main fishing ports in Penghu County were also used for empirical discussion. The study results showed that Magong Fishing Port was the first choice for transformation, followed by Chikan Fishing Port. The results of this study can be used as a reference for fishermen and officials in developing a subsidy scheme for fishing boat operation, and they can be used as a reference for transforming traditional fisheries in outlying islands into recreational fishing to develop recreational fishery boats and leisure tourism industries. This research can help fishermen to attach importance to the development of recreational fishing activities and promote the stable growth of the fishery industry environment.
Thirty-two new diosgenin derivatives were designed, synthesized, and evaluated for their cytotoxic activities in three human cancer cell lines (A549, MCF-7, and HepG2) and normal human liver cells ...(L02) using an MTT assay in vitro. Most compounds, especially 8, 18, 26, and 30, were more potent when compared with diosgenin. The structure–activity relationship results suggested that the presence of a succinic acid or glutaric acid linker, a piperazinyl amide terminus, and lipophilic cations are all beneficial for promoting cytotoxic activity. Notably, compound 8 displayed excellent cytotoxic activity against HepG2 cells (IC50 = 1.9 μM) and showed relatively low toxicity against L02 cells (IC50 = 18.6 μM), showing some selectivity between normal and tumor cells. Studies on its cellular mechanism of action showed that compound 8 induces G0/G1 cell cycle arrest and apoptosis in HepG2 cells. Predictive studies indicated that p38α mitogen-activated protein kinase (MAPK) is the optimum target of 8 based on its 3D molecular similarity, and docking studies showed that compound 8 fits well into the active site of p38α-MAPK and forms relatively strong interactions with the surrounding amino acid residues. Accordingly, compound 8 may be used as a promising lead compound for the development of new antitumor agents.
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