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1.
Environ Sci Pollut Res Int ; 30(47): 103776-103787, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37695486

ABSTRACT

In the face of intensifying climate change-induced environmental problems, understanding the causal relationship between carbon dioxide (CO2) emissions and socioeconomic factors is crucial for achieving sustainable development. This study investigates how the causal relationships between renewable energy, information and communication technology (ICT), logistics networks, economic growth, industrialization, and energy intensity impact sustainable development using a panel dataset drawn from 104 countries and covering 2006 to 2019. Methodologically, panel unit root, panel co-integration, and Granger causality tests are employed as robust econometric techniques. The results of the panel unit root and co-integration tests confirm the stationarity of the variables and reveal significant long-term relationships among them throughout the empirical analysis period. Notably, the panel FMOLS and DOLS estimates indicate a positive effect of RE and ICT on reducing CO2 emissions, whereas GDP and energy intensity have a negative impact on CO2 emissions reduction. Moreover, the pairwise Granger causality test findings indicate bidirectional causal relationships between RE and CO2, IND and CO2, ICT and RE, IND and RE, GDP and ICT, as well as IND and ICT. The study recommends providing policy support, including for technological development and innovation, towards establishing a system that fosters sustainable development.


Subject(s)
Carbon Dioxide , Communication , Information Technology , Economic Development , Renewable Energy , Technology
2.
Transportation (Amst) ; : 1-27, 2022 Aug 19.
Article in English | MEDLINE | ID: mdl-36033421

ABSTRACT

This study investigates the causal relationship between logistics efficiency and factors affecting the logistics environment, such as industrialization, urbanization, and CO2 emissions. With the expectation that logistics efficiency will contribute to economic growth and enhance country competitiveness in the near future, it is necessary to confirm the impact of each factor on different transportation modes, such as maritime and air transport. To this end, this study identifies causal relationships between the factors affecting the logistics environment and specific modes of transportation using data from 2010 to 2018. We employed the panel unit root test, panel co-integration test, fully modified OLS (FMOLS), panel dynamic OLS (DOLS), and panel VECM Granger causality tests for the estimations. The results revealed that factors affecting the logistics environment have different effects depending on the modes of transportation. For maritime transportation, long-run bidirectional causal associations were found between port volume, total exports, industrialization, and urbanization. This implies that export promotion and the resulting economic and social environment changes can increase port throughput; this increase can, in turn, develop and improve economic growth and factors affecting the logistics environment. In contrast, for air transport, we detected a long-run, unidirectional causal relationship among these variables and air volume changes with growing exports, urbanization, and industrialization. Thus, this study suggests a theoretical framework for analyzing the causal relationship between the factors affecting the logistics environment and each mode of transportation, providing insights for policymakers to promote logistics efficiency.

3.
Article in English | MEDLINE | ID: mdl-28335565

ABSTRACT

The objective of this study was to investigate the aquatic-toxic effects of glyoxal-containing cellulose ether with four different glyoxal concentrations (0%, 1.4%, 2.3%, and 6.3%) in response to global chemical regulations, e.g., European Union Classification, Labeling and Packaging (EU CLP). Toxicity tests of glyoxal-containing cellulose ether on 11 different microbial strains, Microcystis aeruginosa, Daphnia magna, and zebrafish embryos were designed as an initial stage of toxicity screening and performed in accordance with standardized toxicity test guidelines. Glyoxal-containing cellulose ether showed no significant toxic effects in the toxicity tests of the 11 freeze-dried microbial strains, Daphnia magna, and zebrafish embryos. Alternatively, 6.3% glyoxal-containing cellulose ether led to a more than 60% reduction in Microcystis aeruginosa growth after 7 days of exposure. Approximately 10% of the developmental abnormalities (e.g., bent spine) in zebrafish embryos were also observed in the group exposed to 6.3% glyoxal-containing cellulose ether after 6 days of exposure. These results show that 6.3% less glyoxal-containing cellulose ether has no acute toxic effects on aquatic organisms. However, 6.3% less glyoxal-containing cellulose ether may affect the health of aquatic organisms with long-term exposure. In order to better evaluate the eco-safety of cellulosic products containing glyoxal, further studies regarding the toxic effects of glyoxal-containing cellulose ether with long-term exposure are required. The results from this study allow us to evaluate the aquatic-toxic effects of glyoxal-containing cellulosic products, under EU chemical regulations, on the health of aquatic organisms.


Subject(s)
Cellulose , Ethers , Glyoxal/toxicity , Water Pollutants, Chemical/toxicity , Animals , Aquatic Organisms/drug effects , Daphnia/drug effects , Dose-Response Relationship, Drug , Glyoxal/administration & dosage , Toxicity Tests , Water Pollutants, Chemical/administration & dosage , Zebrafish/metabolism
4.
Restor Dent Endod ; 39(3): 220-5, 2014 Aug.
Article in English | MEDLINE | ID: mdl-25110647

ABSTRACT

A fiber-reinforced composite (FRC) fixed prosthesis is an innovative alternative to a traditional metal restoration, as it is a conservative treatment method. This case report demonstrates a detailed procedure for restoring a missing anterior tooth with an FRC. A 44-year-old woman visited our department with an avulsed tooth that had fallen out on the previous day and was completely dry. This tooth was replanted, but it failed after one year. A semi-direct technique was used to fabricate a FRC fixed partial prosthesis for its replacement. The FRC framework and the pontic were fabricated using a duplicated cast model and nanofilled composite resin. Later on, interproximal contact, tooth shape, and shade were adjusted at chairside. This technique not only enables the clinician to replace a missing tooth immediately after extraction for minimizing esthetic problems, but it also decreases both tooth reduction and cost.

5.
Rapid Commun Mass Spectrom ; 27(1): 143-51, 2013 Jan 15.
Article in English | MEDLINE | ID: mdl-23239327

ABSTRACT

RATIONALE: Dissociation reactions of protonated amino acids (AAs) can be used as models for the fragmentation of protonated peptides. Atmospheric pressure chemical ionization mass spectrometry (APCI-MS) provides a great deal of structural information in a short analysis time. METHODS: In APCI-MS, the fragmentation patterns can be obtained by varying the cone voltage and some fragment ions are produced that can be used to identify the structure of an analyte. In general, the fragmentation of AAs has used liquid chromatography/tandem mass spectrometry (LC/MS/MS). However, we studied the fragmentation of protonated AAs using a single quadrupole mass spectrometer. RESULTS: The principal fragment ions were [M + H - H(2)O - CO](+), [M + H - H(2)O](+), and [M + H - NH(3)](+). AAs that only generated [M + H - H(2)O - CO](+) were alanine, glycine, histidine, isoleucine, leucine, proline, phenylalanine, and valine. AAs that generated [M + H - H(2)O](+) and [M + H - H(2)O - CO](+) were aspartic acid, glutamic acid, serine, and threonine, while AAs that generated [M + H - NH(3)](+) and [M + H - H(2)O - CO](+) were asparagine, cysteine, glutamine, methionine, tryptophan, and tyrosine. Arginine and lysine generated [M + H - H(2)O](+) and [M + H - NH(3)](+). CONCLUSIONS: The relative abundances of the fragment ions increased with increase in the cone voltage. The experimental results were explained by the favorability of the intermediate structure and the stability of the fragment ion structure. The specific fragmentation patterns could be used for differentiating underivatized AAs.


Subject(s)
Amino Acids/chemistry , Mass Spectrometry/methods , Atmospheric Pressure , Ions/chemistry , Protons
6.
Restor Dent Endod ; 37(4): 240-4, 2012 Nov.
Article in English | MEDLINE | ID: mdl-23430343

ABSTRACT

Crown reattachment is the most conservative treatment which can be used to restore fractured tooth, presumably with sufficient strength, while maintaining original contour, incisal translucency, and reducing chair time and cost.However, in case of crown fracture with pin-point pulp exposure, we should cautiously minimize the irritation to the pulp and consider pre-treatment pulpal status, choice of pulp capping materials, choice of bonding system and treatment sequence during crown reattachment procedures. This case reports the considerations while crown reattachment with direct pulp capping using calcium hydroxide (Dycal, Dentsply Caulk).

7.
J Cardiovasc Ultrasound ; 19(1): 38-40, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21519492

ABSTRACT

We describe here a 26-year-old woman who presented confusion and right hemiparesis due to embolic obstruction of left internal carotid artery and middle cerebral artery. Transthoracic echocardiography showed structurally normal mitral valve with hypermobile echogenic material suggesting vegetation. The vegetation was disappeared after antimicrobial treatment without surgery.

8.
J Mass Spectrom ; 46(5): 496-501, 2011 May.
Article in English | MEDLINE | ID: mdl-21500307

ABSTRACT

Alkali metal cations easily form complexes with proteins in biological systems; understanding amino acid clusters with these cations can provide useful insight into their behaviors at the molecular level including diagnosis and therapy of related diseases. For the purpose of characterization of basic interaction between amino acids and alkali metal, each of the 20 naturally occurring amino acids were ionized in the presence of lithium, sodium and potassium cations by electrospray ionization, and the resulting product ions were analyzed. We focus our attention on the gas phase alkali metal ion-proton exchanged complexes in current study, specifically complexes with serine, threonine, asparagine and glutamine, which share characteristic pattern unlike other amino acids. All amino acids generated [M + H](+) and [M + Na](+) ions, where M stands for the neutral amino acid. Serine, threonine, asparagine and glutamine generated cluster ions of [nM - nH + (n + 1)Na](+) and [nM - (n - 1)H + (n - 1)Na + K](+) , where n = 1-7. While the (M - H + Li) and (M - H + K) species were not observed, the neutral (M - H + Na) species formed by proton-sodium cation exchange had a highly stable cyclic structure with ketone and amine ligand sites, suggesting that (M - H + Na) serves as a building block in cluster ion formation. Cluster ion intensity distributions of [nM - nH + (n + 1)Na](+) and [nM - (n - 1)H + (n - 1)Na + K](+) showed a magic number at n = 3 and 4, respectively. Extensive B3LYP-DFT quantum mechanical calculations were carried out to elucidate the geometry and energy of the cluster ions, and they provided a reasonable explanation for the stability and structure of the cluster ions.


Subject(s)
Amino Acids/chemistry , Hydrogen/chemistry , Metals, Alkali/chemistry , Spectrometry, Mass, Electrospray Ionization/methods , Models, Molecular
9.
Cancer Genet Cytogenet ; 198(2): 162-5, 2010 Apr 15.
Article in English | MEDLINE | ID: mdl-20362232

ABSTRACT

Klinefelter syndrome (KS) is the most commonly diagnosed X chromosome aneuploid syndrome among males. The association between hematologic malignancies such as non-Hodgkin lymphoma and leukemia and KS has been established recently on the basis of numerous case reports and a large cohort study. The risk of chronic myeloproliferative disease (MPD) as a hematologic malignancy in KS, however, has not been evaluated to date. Moreover, to our knowledge, there is only one case report that observed MPD in a patient with KS. Even though the Janus kinase 2 (JAK2) mutation was considered the primary cause in the pathogenesis of MPD, the mutation status was not described in that report. We found JAK2 V617F mutation-positive essential thromobocythemia (ET) in a patient with KS. To the best of our knowledge, this case represents the first case report of JAK2 V617F mutation in a patient with KS. Furthermore, we also suggest the hypothesis that X chromosome aneuploidy as a "pre-JAK2" cytogenetic change may be associated with the development of clonal hematopoiesis and carcinogenesis, because of the finding of higher oncogenic potential of extra X chromosome. In this study, we present the first report of JAK2 V617F-positive ET in a patient with KS, as well as a review of the relevant literature.


Subject(s)
Janus Kinase 2/genetics , Klinefelter Syndrome/genetics , Thrombocythemia, Essential/genetics , Adult , Amino Acid Substitution/genetics , Chromosome Banding , Humans , Janus Kinase 2/metabolism , Klinefelter Syndrome/complications , Male , Mutation, Missense/physiology , Phenylalanine/genetics , Thrombocythemia, Essential/complications , Valine/genetics
10.
Rapid Commun Mass Spectrom ; 22(16): 2580-6, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18646250

ABSTRACT

Ionization efficiencies and fragmentation patterns of cyanoacrylate ultraviolet (UV) absorbers, Uvinul 3035 and Uvinul 3039, were studied using liquid chromatography/atmospheric pressure chemical ionization mass spectrometry (LC/APCI-MS). Solvent effect on the ionization efficiencies was investigated using methanol, ethanol, acetone, and chloroform. The fragmentation patterns were also investigated by varying the fragmentor voltage. Solvated ions, the [M+H + solvent](+) of methanol, ethanol, and acetone were detected, but the [M+H + chloroform](+) ion was not observed. For Uvinul 3039 in chloroform, the [M+CHCl(2)](+) ion was detected instead of the solvated ion. Relative abundance of the solvated ion was decreased by increasing the fragmentor voltage. Fragment ions of m/z 250, 232, and 204 were detected and their abundance increased with an increase in the fragmentor voltage. The m/z 250 ion can be accounted for by a McLafferty rearrangement. The fragment ions of m/z 232 and 204 were formed not only by subsequent fragmentations of the m/z 250 ion, but also by ion-molecule reactions of solvent ion and neutral analyte.

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