Suchergebnisse

Preface -- Contents -- About the Author -- List of Figures -- 1 An Aggregative Model of Unemployment, Cycles, and Growth -- 1.1 Introduction -- 1.2 Static Structure of the Model -- 1.2.1 Goods Market -- 1.2.2 Labor Market -- 1.2.3 Asset Markets -- 1.2.4 Quasi Short-Run Equilibrium -- 1.3 Dynamic Equations -- 1.3.1 Some Dynamic Assumptions -- 1.3.2 Change of Variables -- 1.3.3 Dynamic Equations -- 1.4 Long-Run Equilibrium -- 1.4.1 Existence and Uniqueness -- 1.4.2 Saddle-Point Stability -- 1.5 Movements on the Stable Manifold -- 1.6 Cyclical Movements -- 1.7 Conclusions -- Appendix -- A.1 Some Mathematical Expressions -- A.1.1 Comparative Statics -- A.1.2 Coefficients of the Linear Dynamic System -- A.1.3 Coefficients of the Characteristic Polynomial -- A.2 Proof of Theorem 2 -- A.3 ∂e/∂k and ∂e/∂w -- A.4 Proof of Theorem 3 -- 2 A Hicksian Two-Sector Model of Cycles and Growth -- 2.1 Introduction -- 2.2 Static Structure of the Model -- 2.3 Quasi Short-Run Equilibrium -- 2.4 Dynamic Equations, Dynamic Inclusions, Long-Run Equilibrium, and Saddle-Point Stability -- 2.5 Investment Allocation and the Sectoral Balance -- 2.6 Saddle-Point Stability of System II -- 2.7 Cycles -- 2.8 Conclusions -- Appendix -- A.1 Proof of Lemma 11 -- A.2 Some Mathematical Expressions Relating to the Balanced Stage -- A.2.1 Comparative Statics -- A.2.2 Coefficients of the Linear System -- A.2.3 Coefficients of the Characteristic Polynomial -- A.3 Proof of Theorem 12 -- A.4 Proof of Lemma 13 -- A.5 Proof of Theorem 14 -- A.6 Proof of (2.47) -- 3 Stabilization Policies and Business Cycle Dynamics -- 3.1 Introduction -- 3.2 The Base Model -- 3.2.1 The Static Structure -- 3.2.2 Dynamics -- 3.3 Balanced-Budget Fiscal Stabilization Policy -- 3.3.1 Static Structure -- 3.3.2 Dynamics -- 3.4 Partially Debt-Financed Fiscal Stabilization Policy -- 3.4.1 Static Structure

OBJECTIVES: The purpose of this research was to develop and validate an analytical method for rapid determination of the exposure of workers to ortho‐phthalaldehyde (OPA) at the ceiling threshold concentration. METHODS: A 2,4‐dinitrophenylhydrazine (DNPH)‐silica cartridge was chosen as a sampler. OPA collected by the DNPH‐silica cartridge was subsequently extracted with 5 mL of acetonitrile. A 50‐µL aliquot of phosphoric acid/acetonitrile solution (2%, v/v) was added to 950 µL of the extraction solution and allowed to stand for 30 minutes at room temperature. This solution was then analyzed by high‐performance liquid chromatography tandem mass spectrometry. The basic characteristics of the proposed method, such as recovery, repeatability, limit of quantification, and storage stability of the samples, were examined. RESULTS: The overall recoveries of OPA from OPA‐spiked DNPH‐silica cartridges were 93.6%‐100.1% with relative standard deviations, representing the repeatability, of 1.5%‐10.8%. The limit of quantification was 0.165 ng/sample. The recovery of OPA from DNPH‐silica cartridges after 5 days of storage in a refrigerator exceeded 95%. CONCLUSIONS: The proposed method enabled the determination of the OPA concentration corresponding to the Threshold Limit Value‐Ceiling of 0.1 ppb recommended by the American Conference of Governmental Industrial Hygienists, with a minimum sampling time of 18 seconds (corresponding to a sampling volume of 300 mL at 25°C and 1 atm). Thus, this method will be useful for estimating worker exposures to OPA.

OBJECTIVES: The present study aimed to develop a method for measuring the ceiling level of ortho‐phthalaldehyde (OPA) exposure and evaluate the ceiling levels of OPA exposure among health care workers who handle disinfectant solutions containing OPA for the disinfection of endoscopes. METHODS: The study consisted of a preliminary survey and main survey. In the preliminary survey, processes involving high‐concentration exposure to OPA were identified by video‐exposure monitoring (VEM). In the main survey, the ceiling levels of OPA exposure for high‐concentration exposure processes identified from the results of the preliminary survey were determined using a measuring method combining sampling using a 2,4‐dinitrophenylhydrazine‐silica cartridge and analysis by high‐performance liquid chromatography tandem mass spectrometry. RESULTS: In the preliminary survey, seven processes involving high‐concentration exposure to OPA were identified by VEM. The duration of each process was short, lasting from 20 seconds to a few minutes. In the main survey, the OPA concentrations for the identified high‐concentration exposure processes ranged from 1.18 to 4.49 ppb, which markedly exceeded the threshold limit value ceiling (TLV‐C) of 0.1 ppb recommended by the American Conference of Governmental Industrial Hygienists. CONCLUSIONS: The method for measuring the ceiling level of OPA exposure was established using VEM and the highly sensitive method of chemical analysis; and we successfully evaluated the ceiling levels of OPA exposure among health care workers engaged in endoscope disinfection. This approach can also be applied to other chemical substances with recommended TLV‐Cs, and important information for reducing exposure can thus be obtained.