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Models of lexical meaning

Lexical semantics is concerned with modeling the meaning of lexicalitems. Its leading questions are how forms and meanings combine, what theymean, how they are used, and of course also how they change. The answers tothese five questions make up the fundamental theoretical assumptions and commitments which underlie different theories of lexical semantics, and they form the basis for their various m

Lessons learned from successful value stream mapping (VSM)

To improve, it’s crucial to see! Vital characteristics of Lean are visualisation and transparency, i.e. allowing everyone to see all what occurs in production. A common tool for this purpose is Value Stream Mapping (VSM). Due to varying flows, performing a successful VSM in construction confers additional challenges. In this paper, lessons learned from successful VSM studies in construction are prTo improve, it’s crucial to see! Vital characteristics of Lean are visualisation and transparency, i.e. allowing everyone to see all what occurs in production. A common tool for this purpose is Value Stream Mapping (VSM). Due to varying flows, performing a successful VSM in construction confers additional challenges. In this paper, lessons learned from successful VSM studies in construction are pr

The study of a kitchen assembly process in industrial housing

The kitchen is the heart of the house where people spend much of their time. It is, therefore, an important room that requires high quality. Because construction is argued to be unproductive and wasteful with low quality, studying a kitchen assemblage in detail is of particular interest due to its complexity with many details. In lean, the visualization and transparency of processes is the core fo

Reaction Mechanism for Olefin Exchange at Chloro Ethene Complexes of Platinum(II)

Synopsis In methanol solutions of Zeise's salt, the parent complex [PtCl3(C2H4)]- as well as its solvolysis product, trans-[PtCl2(C2H4)(MeOH)], exchange rapidly with free ethene. The olefin exchange process, which is largely entropy controlled, involves the substitution labile site trans to the coordinated ethene. Abstract Complex equilibria in methanol/chloroform/dichloromethane solutions contain

Kinetics and Mechanism for Formation of Olefin Complexes in the Reaction between Palladium(II) and Maleic Acid

Complex formation between Pd(H2O)(4)(2+) and maleic acid (H(2)A) has been studied at 25 degrees C and 2.00 M ionic strength in acidic aqueous solution. Reaction takes place with 1:1 stoichiometry. The kinetics has been followed by use of stopped-flow spectrophotometry under pseudo-first-order conditions with maleic acid in excess. In the concentration ranges 0.01 less than or equal to [H(2)A](tot)

Iron-Manganese Redox Processes and Synergism in the Mechanism for Manganese-Catalyzed Autoxidation of Hydrogen Sulfiite

SynopsisOn the basis of kinetic studies of the manganese-catalyzed autoxidation of sulfite and thermodynamic data for iron−manganese redox processes and manganese(II) and -(III) protolysis equilibria, the catalytically active species in the autoxidation is concluded to be a mixed-valence oxo-bridged manganese(II,III) complex. Iron−manganese synergism and triggering of the chain reaction by small c

Kinetics and mechanism for reduction of trans-dichlorotetracyanoplatinate(IV) by tetraammineplatinum(II) and bis(ethylenediammine)platinum(II)

Reduction of trans-[Pt(CN)(4)Cl-2](2-) by [Pt(NH3)(4)](2+) and [Pt(en)(2)](2+) was studied at 25 degrees C in the range 0 less than or equal to [Cl-] less than or equal to 0.4 M by use of stopped-flow spectrophotometry. The stoichiometry [Pt(IV)]:[Pt(II)] is 1:1. Rapid-scan spectra show clear-cut isosbestic points, indicating that no reaction intermediates are accumulated to a significant amount.

Kinetics for interaction of the thione unit in 4-thio-2'-deoxyuridine and 4-thiouridine 5'-monophosphate with rapidly reacting gold(III) complexes

Reactions of 4-thio-2′-deoxyuridine d(s4U) and 4-thiouridine 5′-monophosphate s4UMP with trans-[AuY2Cl2]+/– (Y = CN– or NH3) have been investigated by conventional and high-pressure stopped-flow spectrophotometry in aqueous solution with 2.9 ⩽ pH ⩽ 7.0. For a given combination of metal complex and sulfur donor the observed second-order rate constants decreased with increasing pH. In the pH range 2

Gene duplications and losses among vertebrate deoxyribonucleoside kinases of the non-TK1 Family

Deoxyribonucleoside kinases (dNKs) salvage deoxyribonucleosides (dNs) and catalyze the rate limiting step of this salvage pathway by converting dNs into corresponding monophosphate forms. These enzymes serve as an excellent model to study duplicated genes and their evolutionary history. So far, among vertebrates only four mammalian dNKs have been studied for their substrate specificity and kinetic

Health, Social, and Economic Variables Associated with Depression Among Older People in Low and Middle Income Countries : World Health Organization Study on Global AGEing and Adult Health

Objective Although depression among older people is an important public health problem worldwide, systematic studies evaluating its prevalence and determinants in low and middle income countries (LMICs) are sparse. The biopsychosocial model of depression and prevailing socioeconomic hardships for older people in LMICs have provided the impetus to determine the prevalence of geriatric depression; t

Pesticide exposure and neurodevelopment in children aged 6–9 years from Talamanca, Costa Rica

Certain pesticides may affect children's neurodevelopment. We assessed whether pesticide exposure was associated with impaired neurobehavioral outcomes in children aged 6–9 years. We conducted a cross-sectional study in 140 children living near banana plantations and plantain farms in the Talamanca County, Costa Rica and assessed their neurobehavioral performance. Exposure was determined by analyz