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In this study, we present a green and economical approach to chemical recycling of commercial polycarbonates and poly-esters, specifically poly(bisphenol A carbonate), poly(ethylene terephthalate), and poly(lactic acid). Our method involves mechanochemical ball-milling of a heterogeneous mixture of plastic and methanol, resulting in quantitative depolymerization to yield monomers or useful chemical units that already have high demands. We found that the energy-intensive step is forming physical contact between the reactants, rather than the chemical methanolysis itself. Mechanochemical ball-milling facilitates sufficient physical contact and energy transfer between plastics and methanol, eliminating the need for solvents and catalysts. Our study demonstrates a practical and sustainable process with minimal chemical input and simple output for the chemical recycling of these plastics. [ABSTRACT FROM AUTHOR]

Developing countries tend to use multilateral dispute settlement procedures less frequently than developed countries because the former lack the requisite economic and legal capacities. However, recent studies on the WTO have found increased use of the dispute settlement mechanism by developing countries. This article argues for the importance of legal capacity in determining the use of the multilateral process, especially within the WTO. Our empirical analysis indicates that (1) prior member country experiences and (2) the availability of legal assistance from the Advisory Centre on WTO Law increase the likelihood of developing countries using the full multilateral legal procedure. [ABSTRACT FROM AUTHOR]

Background: The relationship between overweight or obesity and low back pain (LBP) has previously been investigated. Several recent studies have focused on the relationship between other indicators of obesity, particularly indicators of fat, and the risk of LBP. However, the results of body composition and LBP have been inconsistent. Methods: All data for the present retrospective, cross-sectional study were extracted from the Korea National Health and Nutrition Examination Survey (KNHANES) versions V-1 and 2 conducted in 2010 and 2011 by the Korea Centers for Disease Control and Prevention. In KNHANES V-1 (2010) and V-2 (2011), those over 50 years of age who completed the surveys on LBP, body weight, and body composition assessed using dual-energy X-ray absorptiometry were included. The multivariable logistic regression analysis was used to examine the relationship between the presence of chronic LBP and body composition adjusting for confounders. Results: We analyzed 3,579 persons who completed the question. In the multivariable analyses adjusting for age and sex, none of the variables, including fat mass and fat-free mass, remained positively or negatively associated with LBP. Additionally, when depression, smoking, alcohol intake, physical activity, diabetes mellitus, osteoporosis, and fat or lean tissue mass were included in the multivariable logistic model, no significant associations were found between all measures of fat mass, fat-free mass, and LBP. Conclusion: The results of this study are contrary to previous studies which concluded that there is a correlation between obesity and fat mass and LBP. Our study shows that LBP is not associated with increased levels of obesity and fat mass. [ABSTRACT FROM AUTHOR]

Mechanochemistry has been extended to various polymer syntheses to achieve efficiency, greenness, and new products. However, many fundamental polymerization reactions have not been explored, although anionic polymerization of vinyl compounds has been pursued under mechanochemical conditions. Two solid monomers, 4-biphenyl methacrylate and 4-vinyl biphenyl, representing methacrylate and styrenic classes, respectively, were reacted with secondary butyl lithium under high-speed ball-milling. The alkyl-anion-promoted polymerization process was established by excluding radical initiation and producing the expected polymers with good efficiency. However, the generally expected features of anionic polymerization, such as molecular weight control and narrow dispersity, were not observed. Analysis of the milling parameters, reaction monitoring, and microstructural analysis revealed that the mechanism of the mechanochemical process differs from that of conventional anionic polymerizations. The mechanical force fractured the newly formed polymer chains via anionic initiation and generated macroradicals, which participated in the polymerization process. The anionic process governs the initiation step and the radical process becomes dominant during the propagation step. [ABSTRACT FROM AUTHOR]

The accumulation of hepatic lipid droplets (LDs) is a hallmark of non-alcoholic fatty liver disease (NAFLD). Appropriate degradation of hepatic LDs and oxidation of complete free fatty acids (FFAs) are important for preventing the development of NAFLD. Histone deacetylase (HDAC) is involved in the impaired lipid metabolism seen in high-fat diet (HFD)-induced obese mice. Here, we evaluated the effect of MS-275, an inhibitor of HDAC1/3, on the degradation of hepatic LDs and FFA oxidation in HFD-induced NAFLD mice. To assess the dynamic degradation of hepatic LDs and FFA oxidation in fatty livers of MS-275-treated HFD C57BL/6J mice, an intravital two-photon imaging system was used and biochemical analysis was performed. The MS-275 improved hepatic metabolic alterations in HFD-induced fatty liver by increasing the dynamic degradation of hepatic LDs and the interaction between LDs and lysozyme in the fatty liver. Numerous peri-droplet mitochondria, lipolysis, and lipophagy were observed in the MS-275-treated mouse fatty liver. Biochemical analysis revealed that the lipolysis and autophagy pathways were activated in MS-275 treated mouse liver. In addition, MS-275 reduced the de novo lipogenesis, but increased the mitochondrial oxidation and the expression levels of oxidation-related genes, such as PPARa, MCAD, CPT1b, and FGF21. Taken together, these results suggest that MS-275 stimulates the degradation of hepatic LDs and mitochondrial free fatty acid oxidation, thus protecting against HFD-induced NAFLD. [ABSTRACT FROM AUTHOR]

The World Trade Organization's dispute settlement mechanism is based on either bilateral bargaining or third-party rulings by a panel or the Appellate Body. When do countries utilize the multilateral procedure, and under what conditions do they opt for a bilateral agreement? Departing from previous studies emphasizing the role of the complainant in shaping the course of the dispute settlement mechanism, this article offers an explanation based on the strategic choices of respondents. This study suggests that the domestic political interests of respondent governments determine the use of the dispute settlement mechanism's multilateral track. We argue that respondent governments choose the multilateral track to seek political cover for domestically unpopular concessions to a complainant. Such cover is required when (1) the dispute at stake has high public salience and (2) the respondent faces an upcoming election. Our hypotheses are tested using World Trade Organization's dispute cases from 1995 to 2017. [ABSTRACT FROM AUTHOR]

Why do some citizens across the globe prioritize the democracy of international organizations (IOs), while others place more emphasis on their effectiveness? We suggest that this difference in attitude may reflect two distinct perspectives on the subjects of IO democracy: (1) a citizen-centered perspective focusing on substantive citizen representation and IO accountability to citizens and (2) a state-centered perspective centering on fair state representation and IO accountability to member states. We examine these two perspectives among citizens worldwide and determine how these perspectives shape preferences for IO democracy and effectiveness. Our empirical analysis uses the latest wave of the World Values Survey, which covers more than 50,000 individuals across 44 countries for the period 2017−2020. We find that citizens' democratic activism and the perceived democratic deficit in domestic governance, which we believe to be associated with a citizen-centered perspective in international governance, do not lead to the prioritization of IO democracy. Instead, the underrepresentation of their country in major IOs and confidence in the national government have a significant and positive association with the prioritization of IO democracy. These results suggest that the prioritization of IO democracy expressed by the public primarily reflects a state-centered perspective of international governance rather than a citizen-centered one. [ABSTRACT FROM AUTHOR]

Recently, the world has witnessed increased participation from nondemocratic countries in international cultural institutions, such as UNESCO's International Assistance (IA) program. This study poses the question of why several authoritarian countries request IA programs more frequently than others do. In addition to economic and international factors, we argue that differences in domestic institutions within autocracies influence the decision-making of such states in requesting IA programs because these programs can be a useful tool for several incumbent regimes to generate public support or maintain their status. We implement negative binomial regressions for 131 authoritarian countries between 1979 and 2014 and demonstrate that politically competitive regimes are more likely to request IA programs than non-competitive ones. The findings suggest that authoritarian regimes with competitive political institutions are likely to utilize the programs of cultural international regimes. Recientemente, el mundo ha observado una mayor participación de países no democráticos en instituciones culturales internacionales, tales como el programa de Asistencia Internacional (International Assistance, IA) de la UNESCO. Este estudio plantea la pregunta de por qué numerosos países autoritarios solicitan programas de IA con más frecuencia que otros países. Además de los factores internacionales y económicos, sostenemos que las diferencias en las instituciones nacionales dentro de las autocracias influyen en la toma de decisiones de tales estados al solicitar programas de IA, ya que estos programas pueden ser una herramienta útil para que los regímenes de turno obtengan el apoyo del público o mantengan su posición. Implementamos regresiones binomiales negativas para 131 países autoritarios entre 1979 y 2014, y demostramos que los regímenes políticamente competitivos son más propensos a solicitar programas de IA que los que no lo son. Los resultados sugieren que es probable que los regímenes autoritarios con instituciones políticas competitivas utilicen los programas de regímenes culturales internacionales. Le monde a récemment été témoin d'une participation accrue des pays non démocratiques aux institutions culturelles internationales, notamment au niveau des programmes d'aide internationale de l'UNESCO. Cette étude s'interroge sur les raisons pour lesquelles plusieurs pays autoritaires demandent des programmes d'aide internationale plus fréquemment que d'autres. En plus des facteurs économiques et internationaux, nous soutenons que les différences dans les institutions nationales des autocraties influencent la prise de décision de ces États lorsqu'ils demandent des programmes d'aide internationale, car ces programmes peuvent être un outil utile pour plusieurs régimes en place pour générer un soutien public ou maintenir leur statut. Nous avons appliqué des régressions binomiales négatives pour 131 pays autoritaires entre 1979 et 2014 et nous démontrons que les régimes politiquement concurrents sont davantage susceptibles de demander des programmes d'aide internationale que les régimes non concurrents. Nos conclusions suggèrent que les régimes dont les institutions politiques sont concurrentes sont susceptibles d'avoir recours aux programmes des régimes culturels internationaux. [ABSTRACT FROM AUTHOR]

A new sequential post‐polymerization modification route has been developed for the synthesis of multifunctional polymers from a simple aldehyde polymer. In the first modification step, a template polymer derived from the radical polymerization of 4‐vinyl benzaldehyde undergoes Rh‐catalyzed hydroacylation with alkenes to furnish a group of ketone polymers. In the second modification step, Schiff base formation with alkoxy ammonium salts introduces a second group—an oxime functionality. Both the steps are highly efficient, introducing evenly distributed dual functionalities at the same position. [ABSTRACT FROM AUTHOR]

A cyclocyanine (CC)-based organic small molecule two-photon (TP) fluorescent probe (CCNa1) was developed for mitochondrial sodium ion sensing. CCNa1 exhibits a low solvatochromic shift and strong TP fluorescence enhancement at 575 nm upon binding to Na+ and is insensitive to other metal ions and to pH. CCNa1 demonstrated fast cell loading ability, biocompatibility, and sensitive response to mitochondrial Na+ influx in live cells and mouse brain tissue. [ABSTRACT FROM AUTHOR]

Imaging and photodynamic therapy through two‐photon excitation can be applied to medical application of deep inside the tissue by minimizing light absorption by the tissue. It is the best solution that can complement the shortcomings of conventional photodynamic therapy. In addition, auto‐fluorescence can be minimized, and damage to normal cells can be avoided through spatial and temporal control. To maximize the image realization and the effect of treatment, a single photosensitizer with high fluorescence quantum yields, two‐photon absorption value, and good 1O2 or reactive oxygen species production performance must be developed. Therefore, recent research related to this topic is summarized. In addition, two‐photon photosensitizers that approach selective imaging and treatment for target diseases and future challenges were discussed. [ABSTRACT FROM AUTHOR]

Background: Endoscopy is the most important tool for gastric cancer diagnosis. However, it relies on naked-eye evaluation by endoscopists, and the histopathologic confirmation is time-consuming. We aimed to visualize and measure the activity of various enzymes through two-photon microscopy (TPM) using fluorescent probes and assess its diagnostic potential in gastric cancer. Methods: β-Galactosidase (β-gal), carboxylesterase (CES), and human NAD(P)H: quinone oxidoreductase (hNQO1) enzyme activities in the normal mucosa, ulcer, adenoma, and gastric cancer biopsy samples were measured using two-photon enzyme probes. The fluorescence emission ratio at long and short wavelengths (Ch2/Ch1) for each probe was comparatively analyzed. Approximately 8,000 – 9,000 sectional images in each group were obtained by measuring the Ch2/Ch1 ratio according to the tissue depth. Each probe was cross-validated by measuring enzymatic activity from a solution containing lysed tissue. Results: Total of 76 subjects were enrolled in this pilot study (normal 21, ulcer 18, adenoma 17, and cancer 20 patients, respectively). There were significant differences in the mean ratio values of β-gal (0.656 ± 0.142 vs. 1.127 ± 0.109, P < 0.001) and CES (0.876 ± 0.049 vs. 0.579 ± 0.089, P < 0.001) between the normal and cancer, respectively. The mean ratio value of cancer tissues was different compared to ulcer and adenoma (P < 0.001). The hNQO1 activity showed no significant difference between cancer and other conditions. Normal mucosa and cancer were visually and quantitatively distinguished through β-gal and CES analyses using TPM images, and enzymatic activity according to depth, was determined using sectional TPM ratiometric images. The results obtained from lysis buffer-treated tissue were consistent with TPM results. Conclusions: TPM imaging using ratiometric fluorescent probes enabled the discrimination of gastric cancer from normal, ulcer, and adenoma. This novel method can help in a visual differentiation and provide quantitative depth profiling in gastric cancer diagnosis. [ABSTRACT FROM AUTHOR]

The Commonwealth of the Northern Mariana Islands (CNMI) recently identified the need to improve its capacity for detecting and tracking land-based sources of pollution (LBSP) in coastal waters, particularly microbial contaminants like fecal indicator bacteria (FIB). Reported here is a baseline study of a suite of host-specific FIB microbial source tracking (MST) markers in the coastal shoreline and reef waters around the island of Saipan. Three sampling campaigns were conducted in September 2017, March 2018, and August 2018. Samples were collected from the nearshore surface waters of Saipan, the reef waters of Saipan Lagoon, and groundwater from beaches along the Saipan Lagoon shoreline. Measurements of submarine groundwater discharge (SGD) into nearshore waters and isotopic source tracking of nitrogen inputs were conducted concurrently with MST. Environmental DNA was extracted from the samples and analyzed by quantitative polymerase chain reaction (qPCR) for MST gene markers of fecal Bacteroidales specifically associated with humans, dogs, cows, and pigs, and for an MST gene marker of Catellicoccus associated with seabirds. MST assessments were combined with local knowledge, assessments of sanitary infrastructure, and routine watershed surveys. This study identified hotspots of human FIB along the western Saipan Lagoon shoreline in both surface waters and groundwater, plus another hotspot of human FIB at a popular tourist bathing area known as the Grotto. FIB hotspots on the Lagoon shoreline coincided with areas of high SGD and nitrogen isotopic data indicating sewage-derived N inputs. It appears that faulty sanitary infrastructure may be contributing to inputs to Saipan Lagoon, while bather shedding is likely a primary input for the Grotto area. Moderate levels of dog fecal contamination were common and widespread across the island. High levels of seabird fecal contamination were more random, both spatially and temporally, and mostly concentrated along the less developed northeast region of Saipan. No significant levels of cow or pig fecal marker were detected in coastal water samples. This study provides demonstration and establishment of analytical capacity to resource management in CNMI for MST technology to aid in trouble-shooting water quality issues involving land-based sources of microbial contaminants to CNMI coastal waters. [ABSTRACT FROM AUTHOR]

The Aid for Trade initiative was launched by the WTO in 2005 to help developing countries build their supply‐side capacity and trade‐related infrastructure to improve their capacity in the global market. This study investigates the impacts of both the tangible and intangible elements of this initiative on the economic, social and political globalisation of recipient countries. Intangible elements of Aid for Trade (aid for trade policy and regulation) may be considered as the software of Aid for Trade, while tangible elements (aid for economic infrastructure and building productive capacity) are the hardware. Countries that receive Aid for Trade can use both types of elements to succeed in globalisation. This research hypothesises that the tangible elements of Aid for Trade have a singular effect on the overall level of globalisation since they are expected to only increase the level of economic globalisation. Moreover, we expect that the intangible elements of Aid for Trade will have multiple effects on the overall level of globalisation as they have an impact on not only economic aspects but also social and political aspects of it. Using the dataset of Aid for Trade from 2002 to 2015, we find that the intangible elements of Aid for Trade have increased the recipients' level of overall globalisation. [ABSTRACT FROM AUTHOR]

How did the COVID-19 pandemic impact foreign direct investment (FDI)? Following the outbreak of COVID-19, the overall volume of FDI inflows plummeted. However, COVID-19’s adverse effects on FDI in host countries exhibited discernible variability contingent upon the characteristics of domestic institutions, particularly the robustness of property rights within these countries. While host countries with strong property rights experienced a mitigated negative impact on FDI, contrary to general expectations, our analysis suggests that host countries with weak property rights may have also evaded a significant reduction in FDI inflows during the pandemic. This was primarily because both strong and weak property rights institutions in host countries conveyed positive signals to investors, which may have incentivized them to continue their investments even amidst the pandemic-induced crisis. Analyzing a time-series cross-sectional dataset of 126 developing countries covering the period 2009–2021, our findings reveal a U-shaped relationship between FDI and property rights. This implies that COVID-19’s impact manifested as a weak negative force on FDI inflows in host countries with weak property rights as well as those with strong property rights. Conversely, host countries with moderately strong property rights tended to suffer a substantial reduction in FDI. [ABSTRACT FROM AUTHOR]

Biological events occur in specific cellular organelles to perform specialized roles in cells and collaborate with other organelles. Various methods have been used to study organelle dynamics, including two-photon microscopy. This technique uses two near-infrared photons as an excitation source to generate high-resolution images over an extended period with minimal photo-toxicity and background noise. This review highlighted the design strategies, photo-physical properties, and bioimaging applications of recent two-photon probes for organelles in live samples. In this review, we focused on the development of two-photon probes specifically localized in the endoplasmic reticulum, Golgi, lipid droplets, lysosomes, plasma membrane, and mitochondria. The summary was limited to research from 2017 onwards. [Display omitted] • Bioimaging analysis of cell organelles using two-photon fluorescent probes are reviewed. • Special attention is given to design strategies and photo-physical properties of two-photon probes for organelles. • Identification of specific analytes and applications in deep live tissues and biomedical research are discussed. [ABSTRACT FROM AUTHOR]

We report an amidine-based small molecule two-photon fluorescent probe (ELP1) for monitoring vesicle transport from the ER to lysosome in live cells. Two-photon microscopy imaging studies indicated that this probe initially localized in the ER and subsequently transferred to lysosomal compartments through vesicular transport. These results may provide an effective tool for studying trafficking-related biology and pathology in real-time. [ABSTRACT FROM AUTHOR]

Insulin-secreting beta cells together with glucagon-producing alpha cells play an essential role in maintaining the optimal blood glucose level in the body, so the development of selective probes for imaging of these cell types in live islets is highly desired. Herein we report the development of a 2-glucosamine-based two-photon fluorescent probe, TP-β, that is suitable for imaging of beta cells in live pancreatic islets from mice. Flow cytometry studies confirmed that TP-β is suitable for isolation of primary beta cells. Moreover, two-photon imaging of TP-β-stained pancreatic islets showed brightly stained beta cells in live islets. Insulin enzyme-linked immunosorbent assays revealed that TP-β has no effect on glucose-stimulated insulin secretion from the stained islet. Finally, to develop a more convenient islet imaging application, we combined our recently published alpha-cell-selective probe TP-α with TP-β to make a "TP islet cocktail". This unique dye cocktail enabled single excitation (820 nm) and simultaneous dual-color imaging of alpha cells (green) and beta cells (red) in live pancreatic islets. This robust TP islet cocktail may serve as a valuable tool for basic diabetic studies. [ABSTRACT FROM AUTHOR]