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1.
Article in English | MEDLINE | ID: mdl-36833751

ABSTRACT

"Land Use and Land Cover Change (LULCC)" is increasingly being affected by ecosystem services value. LULCC patterns have been subjected to significant changes over time, primarily due to an ever-increasing population. It is rare to attempt to analyze the influence of such changes on a large variety of ecosystem benefits in Madagascar island. The economic value of ecosystem services in Madagascar island is evaluated throughout the period from 2000 to 2019. The expansion of the human population affects the changing value of ecosystem services directly. The PROBA-V SR time series 300 m spatial resolution cover of land datasets from the "Climate Change Initiative of the European Space Agency (ESA)" were used to measure the values of ecosystem activities and the changes in those values caused by land use. A value transfer method was used to evaluate the value of ecosystem services to land use changes on Madagascar island. The findings show that from 2000 to 2019, at the annual rate of 2.17 percent, Madagascar island's ecosystem service value (ESV) grew to 6.99 billion US dollars. The components that greatly contributed to the total change of ESV were waste treatment, genetic resources, food production, and habitat/refugia. These components in 2000 contributed 21.27%, 20.20%, 17.38%, and 13.80% of the total ESV, and 22.55%, 19.76%, 17.29%, and 13.78% of the total ESV in 2019, respectively. Furthermore, it was found that there was a great change in LULCC. From 2000 to 2019, bare land, built-up land, cultivated land, savannah, and wetland increased while other LULCC types decreased. The sensitivity coefficient ranged from 0.649 to 1.000, <1, with forestland registering the highest values. Wetland is in the second position for the most important land cover category in Madagascar, considering the total value of the ecosystem. The value of ecosystem benefits per unit of the land area was higher on cultivated land, despite the relatively low fraction of cultivated land area across these eras. The sensitivity indices of seven land types from 2000 to 2019 were mapped to understand better the geographical distribution patterns of ESV's "equivalent value coefficient" (VC) across various land uses. It is suggested that the ESV should be included in Madagascar's government land-use plan to manage it effectively and efficiently with fewer negative effects on the ecosystem.


Subject(s)
Conservation of Natural Resources , Ecosystem , Humans , Madagascar , Forests , Africa
2.
Front Psychol ; 12: 746467, 2021.
Article in English | MEDLINE | ID: mdl-34675852

ABSTRACT

The outgrowth of e-commerce has advanced the development of countries' economies. Today, online marketplaces are targeting not only their local customers but are also spreading their interests overseas, expanding cross-border e-commerce. The current study aims to analyze the interaction of customer's personal traits, such as national culture, disposition to trust, and perceived trustworthiness, and their effect on the purchase intention within different e-commerce contexts. The contexts are chosen based on the country-of-origin parameter and serve as the moderator in the research model. Both direct and indirect effects of cultural dimensions on trustworthiness and purchase intention are analyzed within the research framework. The data for the analysis are randomly collected among the Russian population and assessed using structural equation modeling (SEM). The analysis results prove the marketplace context moderates the interaction of customers' personal traits among each other and their effect on the purchase intention. The study shows that dimensions of national culture have a more substantial effect on perceived trustworthiness and purchase intention in the Chinese marketplace context. The current study contributes to the analysis of customer behavior patterns within context, expanding context-related research direction. It increases the specificity of the culture and trustworthiness research and deepens the understanding of country-of-origin moderating effect in e-commerce. Moreover, addressing a high-level uncertainty avoidance culture within the research framework, the study diversifies the existing set of analyzed cultures in the e-commerce environment. The current study is applicable both in domestic and in cross-border e-commerce practice, broadening the understanding of consumer behavior patterns. The research model is relevant for the analysis of trust-effected behavioral outcomes.

3.
Front Psychol ; 12: 689311, 2021.
Article in English | MEDLINE | ID: mdl-34557131

ABSTRACT

This research investigates the impact of transformational leadership (TL) style on project success (PS) in the indirect effect of serial mediation of team-building and teamwork quality (TWQ). A quantitative research approach was used for this study. Data were gathered from 374 professional information system development (ISD) project managers in Pakistan. The hypotheses were tested using regression analysis with bootstrapping. Both team-building and teamwork independently and serially mediate the relationship between the TL and PS of the project managers, respectively. The TL style of the project manager intensifies PS with team-building practices (TBP) and TWQ. The TL boosts TWQ in terms of communication, coordination, and cohesion to achieve a successful project. The findings suggest that TL is associated with PS through serial mediation of team-building and teamwork. No research to date has used this nascent methodology to explore the association between TL and PS.

4.
Front Psychol ; 12: 673771, 2021.
Article in English | MEDLINE | ID: mdl-34385954

ABSTRACT

The emergence of coronavirus disease 2019 (COVID-19) has considerably changed global food production, processing, and consumption at different levels. Sojourners are among those who have experienced a higher level of food insecurity during the crisis of the COVID-19 outbreak. The current research aimed to investigate the immediate consumption behavioral intentions of the Pakistani international students in the People's Republic of China (PRC) during the wake of COVID-19 pandemic. This study applied the Theory of Planned Behavior (TPB) and background factors of food safety and health consciousness that influence the consumption behavioral intention of Pakistani students toward unfamiliar local food in China. A relational model was analyzed where food safety and health consciousness were hypothesized to serve as background variables associated with TPB components. Moreover, the indirect effects of food safety and health consciousness on behavioral intentions were assessed. The data were collected through convenience samples from 462 Pakistani international students and were analyzed through partial least square structural equation modeling (PLS-SEM). The results confirmed that food safety and health consciousness were positively associated with attitude (ATT), subjective norm (SN), and perceived behavioral control (PBC). However, food safety and health consciousness were indirectly associated with the behavioral intention only through ATT and SN. The results highlighted the role of food safety and health consciousness as important antecedents of classical TPB components that affect intentions and behaviors to avoid unfamiliar local food in a migrated context. The present study provides enlightenment to those who aim to investigate the consumption behavioral intentions of sojourners in the wake of the pandemic situation based on food safety and health consciousness. The findings of the current study are also applicable to general consumption patterns in the food sector.

5.
J Phys Chem B ; 118(47): 13554-63, 2014 Nov 26.
Article in English | MEDLINE | ID: mdl-25365737

ABSTRACT

We describe a statistical thermodynamic approach to analyzing urea-dependent volumetric properties of proteins. We use this approach to analyze our urea-dependent data on the partial molar volume and adiabatic compressibility of lysozyme, apocytochrome c, ribonuclease A, and α-chymotrypsinogen A. The analysis produces the thermodynamic properties of elementary urea-protein association reactions while also yielding estimates of the effective solvent-accessible surface areas of the native and unfolded protein states. Lysozyme and apocytochrome c do not undergo urea-induced transitions. The former remains folded, while the latter is unfolded between 0 and 8 M urea. In contrast, ribonuclease A and α-chymotrypsinogen A exhibit urea-induced unfolding transitions. Thus, our data permit us to characterize urea-protein interactions in both the native and unfolded states. We interpreted the urea-dependent volumetric properties of the proteins in terms of the equilibrium constant, k, and changes in volume, ΔV0, and compressibility, ΔKT0, for a reaction in which urea binds to a protein with a concomitant release of two waters of hydration to the bulk. Comparison of the values of k, ΔV0, and ΔKT0 with the similar data obtained on small molecules mimicking protein groups reveals lack of cooperative effects involved in urea-protein interactions. In general, the volumetric approach, while providing a unique characterization of cosolvent-protein interactions, offers a practical way for evaluating the effective solvent accessible surface area of biologically significant fully or partially unfolded polypeptides.


Subject(s)
Chymotrypsinogen/chemistry , Cytochromes c/chemistry , Muramidase/chemistry , Ribonuclease, Pancreatic/chemistry , Urea/chemistry , Circular Dichroism , Egg Proteins/chemistry , Protein Folding , Thermodynamics
6.
Article in English | MEDLINE | ID: mdl-23668401

ABSTRACT

This chapter is a review on physical and chemical properties, methods of preparation, analysis, as well as pharmacodynamics and pharmacokinetics of Alendronate sodium (4-amino-1-hydroxybutane-1,1-diphosphonic acid sodium salt), a bone metabolism regulator, indicated for the treatment of excessive bone resorption and osteoporosis.


Subject(s)
Alendronate/chemistry , Bone Density Conservation Agents/chemistry , Alendronate/analysis , Alendronate/chemical synthesis , Alendronate/pharmacokinetics , Animals , Crystallography , Humans , Solubility , Terminology as Topic
7.
Article in English | MEDLINE | ID: mdl-23668408

ABSTRACT

Paroxetine hydrochloride (3S-trans)-3-[(1,3-benzodioxol-5-yloxy)methyl]-4-(4-fluorophenyl)-piperidine hydrochloride (or (-)-(3S,4R)-(4-(p-fluorophenyl)-3-[[3,4-(methylenedioxy)-phenoxy]methyl]piperidine hydrochloride), a phenylpiperidine derivative, is a selective serotonin reuptake inhibitor. Paroxetine is indicated for the treatment of depression, generalized anxiety disorder, obsessive-compulsive disorder, panic disorder, posttraumatic stress disorder, and social anxiety disorder. The physicochemical properties, spectroscopic data (1D and 2D NMR, UV, FT-IR, MS, PXRD), stability, methods of preparation and chromatographic methods of analysis of pharmaceutical, and biological samples of paroxetine are documented in this review. Pharmacokinetics, metabolism, and pharmacological effects are also discussed.


Subject(s)
Paroxetine/analysis , Selective Serotonin Reuptake Inhibitors/analysis , Animals , Chromatography , Drug Stability , Humans , Paroxetine/chemistry , Paroxetine/pharmacokinetics , Spectrum Analysis
8.
Biophys Chem ; 134(3): 185-99, 2008 May.
Article in English | MEDLINE | ID: mdl-18342425

ABSTRACT

We determined the partial molar volumes, V degrees , and adiabatic compressibilities, K degrees (S), of N-acetyl amino acids with neutralized carboxyl termini, N-acetyl amino acid amides, and N-acetyl amino acid methylamides between 18 and 55 degrees C. The individual compounds in the three classes have been selected so as to collectively cover the 20 naturally occurring amino acid side chains. We interpret our experimental results in terms of the volumetric contributions and hydration properties of individual amino acid side chains and their constituent atomic groups. We also conducted pH-dependent densimetric and acoustic measurements to determine changes in volume and compressibility accompanying protonation of the aspartic acid, glutamic acid, histidine, lysine, and arginine side chains. We use our resulting data to develop an additive scheme for calculating the partial molar (specific) volume and adiabatic compressibility of fully extended polypeptide chains as a function of pH and temperature. We discuss the differences and similarities between our proposed scheme and the reported additive approaches. We compare our calculated volumetric characteristics of the fully extended conformations of apocytochrome c and apomyoglobin with the experimental values measured in water (for apocytochrome c) or acidic pH (for apomyoglobin). At these respective experimental conditions, the two proteins are unfolded. However, the comparison between the calculated and experimental volumetric characteristics suggests that neither apocytochrome c nor apomyoglobin are fully unfolded and retain a sizeable core of solvent-inaccessible groups.


Subject(s)
Protein Folding , Proteins/chemistry , Proteins/metabolism , Amino Acids/chemistry , Hydrogen-Ion Concentration , Ions/chemistry , Protein Denaturation , Temperature , Water/chemistry
9.
Biochemistry ; 45(35): 10563-71, 2006 Sep 05.
Article in English | MEDLINE | ID: mdl-16939208

ABSTRACT

We employed salt-dependent differential scanning calorimetric measurements to characterize the stability of six oligomeric DNA duplexes (5'-GCCGGAXTGCCGG-3'/5'-CCGGCAYTCCGGC-3') that contain in the central XY position the GC, AT, GG, CC, AA, or TT base pair. The heat-induced helix-to-coil transitions of all the duplexes are associated with positive changes in heat capacity, DeltaC(p), ranging from 0.43 to 0.53 kcal/mol. Positive values of DeltaC(p) result in strong temperature dependences of changes in enthalpy, DeltaH degrees, and entropy, DeltaS degrees , accompanying duplex melting and cause melting free energies, DeltaG degrees, to exhibit characteristically curved shapes. These observations suggest that DeltaC(p) needs to be carefully taken into account when the parameters of duplex stability are extrapolated to temperatures distant from the transition temperature, T(M). Comparison of the calorimetric and van't Hoff enthalpies revealed that none of the duplexes studied in this work exhibits two-state melting. Within the context of the central AXT/TYA triplet, the thermal and thermodynamic stabilities of the duplexes in question change in the following order: GC > AT > GG > AA approximately TT > CC. Our estimates revealed that the thermodynamic impact of the GG, AA, and TT mismatches is confined within the central triplet. In contrast, the thermodynamic impact of the CC mismatch propagates into the adjacent helix domains and may involve 7-9 bp. We discuss implications of our results for understanding the origins of initial recognition of mismatched DNA sites by enzymes of the DNA repair machinery.


Subject(s)
Base Composition , Base Pair Mismatch , Base Sequence , DNA/chemistry , Transition Temperature , Calorimetry, Differential Scanning , Circular Dichroism , Entropy , Molecular Sequence Data , Nucleic Acid Conformation , Nucleic Acid Denaturation , Nucleic Acid Renaturation
10.
J Am Chem Soc ; 128(6): 1914-21, 2006 Feb 15.
Article in English | MEDLINE | ID: mdl-16464093

ABSTRACT

We characterized the interactions of meso-tetrakis(4N-(2-hydroxyethyl)pyridinium-4-yl) porphyrin (TEtOHPyP4), meso-tetrakis(4N-allylpyridinium-4-yl) porphyrin (TAlPyP4), and meso-tetrakis(4N-metallylpyridinium-4-yl) porphyrin (TMetAlPyP4) with the poly(rA)poly(rU) and poly(rI)poly(rC) RNA duplexes between 18 and 45 degrees C by employing circular dichroism, light absorption, and fluorescence intensity spectroscopic measurements. Our results suggest that TEtOHPyP4 and TAlPyP4 intercalate into the poly(rA)poly(rU) and poly(rI)poly(rC) host duplexes, while TMetAlPyP4 associates with these RNA duplexes by forming outside-bound, self-stacked aggregates. We used our temperature-dependent absorption titration data to determine the binding constants and stoichiometry for each porphyrin-RNA binding event studied in this work. From the temperature dependences of the binding constants, we calculated the binding free energies, DeltaG(b), enthalpies, DeltaH(b), and entropies, DeltaS(b). For each RNA duplex, the binding enthalpy, DeltaH(b), is the most favorable for TEtOHPyP4 (an intercalator) followed by TAlPyP4 (an intercalator) and TMetAlPyP4 (an outside binder). On the other hand, for each duplex, external self-stacking of TMetAlPyP4 produces the most favorable change in entropy, DeltaS(b), followed by the intercalators TAlPyP4 and TEtOHPyP4. Thus, our results suggest that the thermodynamic profile of porphyrin-RNA binding may correlate with the binding mode. This correlation reflects the differential nature of molecular forces that stabilize/destabilize the two modes of binding-intercalation versus external self-stacking along the host duplex.


Subject(s)
Poly A-U/chemistry , Poly I-C/chemistry , Porphyrins/chemistry , RNA, Double-Stranded/chemistry , Kinetics , Solubility , Spectrometry, Fluorescence , Spectrophotometry , Thermodynamics , Water/chemistry
11.
J Am Chem Soc ; 126(50): 16387-94, 2004 Dec 22.
Article in English | MEDLINE | ID: mdl-15600340

ABSTRACT

We report high-resolution differential scanning calorimetric data on the poly(dAdT)poly(dAdT), poly(dA)poly(dT), poly(dIdC)poly(dIdC), poly(dGdC)poly(dGdC), poly(rA)poly(rU), and poly(rI)poly(rC) nucleic acid duplexes. We use these data to evaluate the melting temperatures, TM, enthalpy changes, DeltaHM, and heat capacity changes, DeltaCP, accompanying helix-to-coil transitions of each polymeric duplex studied in this work at different NaCl concentrations. In agreement with previous reports, we have found that DeltaCP exhibits a positive, nonzero value, which, on average, equals 268 +/- 33 J mol(-1) K(-1). With DeltaCP, we have calculated the transition free energies, DeltaG, enthalpies, DeltaH, and entropies, DeltaS, for the duplexes as a function of temperature. Since, DeltaG, DeltaH, and DeltaS all strongly depend on temperature, the thermodynamic comparison between DNA and/or RNA duplexes (that may differ from one another with respect to sequence, composition, conformation, etc.) is physically meaningful only if extrapolated to a common temperature. We have performed such comparative analyses to derive differential thermodynamic parameters of formation of GC versus AT, AU, and IC base pairs as well as B' versus A and B helix conformations. We have proposed some general microscopic interpretations for the observed sequence-specific and conformation-specific thermodynamic differences between the duplexes.


Subject(s)
Polydeoxyribonucleotides/chemistry , Base Pairing , Calorimetry, Differential Scanning , Chemical Phenomena , Chemistry, Physical , Drug Stability , Hydrogen Bonding , Nucleic Acid Conformation , Poly dA-dT/chemistry , Thermodynamics
12.
J Mol Biol ; 341(2): 551-63, 2004 Aug 06.
Article in English | MEDLINE | ID: mdl-15276843

ABSTRACT

We report the relative molar sound velocity increments, [U], partial molar volumes, V(o), and partial molar adiabatic compressibilities, K(S)(o), of the Li(+), Na(+), K(+), Rb(+), Cs(+), NH(4)(+), and N(CH(3))(4)(+) salts of poly(dAdT)poly(dAdT), poly(dGdC)poly(dGdC), poly(dIdC)poly(dIdC), poly(rA)poly(rU), poly(rG)poly(rC), poly(rI)poly(rC), and poly(rU) at 25 degrees C. When analyzing these data, we take into account the Donnan membrane equilibrium effect. Comparison between the values of [U], V(o), and K(S)(o) exhibited by the nucleic acid salts and respective chlorides (LiCl, NaCl, KCl, RbCl, CsCl, NH(4)Cl, and N(CH(3))(4)Cl) yields information about the state of counterion hydration in the vicinity of each nucleic acid structure studied here. Our analysis reveals that the poly(dGdC)poly(dGdC), poly(dIdC)poly(dIdC), and poly(rI)poly(rC) duplexes and single-stranded poly(rU) do not significantly influence the hydration properties of their condensed counterions. In the vicinity of these polymers, counterions retain their full hydration shells (within +/-15%). By contrast, counterions condensed around the poly(dAdT)poly(dAdT), poly(rA)poly(rU), and poly(rG)poly(rC) duplexes are significantly dehydrated and retain, respectively, only 65(+/-18)%, 34(+/-21)%, and 33(+/-9)% of their original hydration shells. Taken together, the volumetric data reported here provide important new information that ultimately may help us understand the central role that hydration and counterions play in modulating the conformational preferences of nucleic acids and the energetics of DNA recognition events.


Subject(s)
Cations, Monovalent/chemistry , DNA/chemistry , Polynucleotides/chemistry , Water/chemistry , Cations, Monovalent/metabolism , DNA/metabolism , Kinetics , Osmolar Concentration , Polynucleotides/metabolism , Thermodynamics , Water/metabolism
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