Taxes and Time Allocation: Evidence from Single Women

Hundreds of papers have investigated how incentives and policies affect hours worked in the market. This paper examines how income taxes affect time allocation in the other two-thirds of the day. Using the Panel Study of Income Dynamics from 1975 to 2004, we analyze the response of single women's housework, labor supply, and other time to variation in tax and transfer schedules across income levels, number of children, states, and time. We find that when the economic reward to participating in the labor force increases, market work increases and housework decreases, with the decrease in housework accounting for approximately two-thirds of the increase in market work. Analysis of repeated cross-sections of time diary data from 1975 to 2004 shows that changes in "home production" account for at least half of the increase in market hours of work in response to policy changes. Data on expenditures from the Consumer Expenditure Survey from 1980 to 2003 show some evidence that expenditures on market goods likely to substitute for housework increase in response to a greater incentive to join the labor force. The baseline estimates imply that the elasticity of substitution between consumption of home and market goods is 2.43. The results are consistent with the classic time allocation model of Becker (1965).

Untargeted Lipidomics of Non-Small Cell Lung Carcinoma Demonstrates Differentially Abundant Lipid Classes in Cancer vs. Non-Cancer Tissue

Lung cancer remains the leading cause of cancer death worldwide and non-small cell lung carcinoma (NSCLC) represents 85% of newly diagnosed lung cancers. In this study, we utilized our untargeted assignment tool Small Molecule Isotope Resolved Formula Enumerator (SMIRFE) and ultra-high-resolution Fourier transform mass spectrometry to examine lipid profile differences between paired cancerous and non-cancerous lung tissue samples from 86 patients with suspected stage I or IIA primary NSCLC. Correlation and co-occurrence analysis revealed significant lipid profile differences between cancer and non-cancer samples. Further analysis of machine-learned lipid categories for the differentially abundant molecular formulas identified a high abundance sterol, high abundance and high m/z sphingolipid, and low abundance glycerophospholipid metabolic phenotype across the NSCLC samples. At the class level, high abundances of sterol esters and cardiolipins were observed suggesting altered stearoyl-CoA desaturase 1 (SCD1) or acetyl-CoA acetyltransferase (ACAT1) activity and altered human cardiolipin synthase 1 or lysocardiolipin acyltransferase activity respectively, the latter of which is known to confer apoptotic resistance. The presence of a shared metabolic phenotype across a variety of genetically distinct NSCLC subtypes suggests that this phenotype is necessary for NSCLC development and may result from multiple distinct genetic lesions. Thus, targeting the shared affected pathways may be beneficial for a variety of genetically distinct NSCLC subtype

Atom Identifiers Generated by a Neighborhood-Specific Graph Coloring Method Enable Compound Harmonization across Metabolic Databases

Metabolic flux analysis requires both a reliable metabolic model and reliable metabolic profiles in characterizing metabolic reprogramming. Advances in analytic methodologies enable production of high-quality metabolomics datasets capturing isotopic flux. However, useful metabolic models can be difficult to derive due to the lack of relatively complete atom-resolved metabolic networks for a variety of organisms, including human. Here, we developed a neighborhood-specific graph coloring method that creates unique identifiers for each atom in a compound facilitating construction of an atom-resolved metabolic network. What is more, this method is guaranteed to generate the same identifier for symmetric atoms, enabling automatic identification of possible additional mappings caused by molecular symmetry. Furthermore, a compound coloring identifier derived from the corresponding atom coloring identifiers can be used for compound harmonization across various metabolic network databases, which is an essential first step in network integration. With the compound coloring identifiers, 8865 correspondences between KEGG (Kyoto Encyclopedia of Genes and Genomes) and MetaCyc compounds are detected, with 5451 of them confirmed by other identifiers provided by the two databases. In addition, we found that the Enzyme Commission numbers (EC) of reactions can be used to validate possible correspondence pairs, with 1848 unconfirmed pairs validated by commonality in reaction ECs. Moreover, we were able to detect various issues and errors with compound representation in KEGG and MetaCyc databases by compound coloring identifiers, demonstrating the usefulness of this methodology for database curation

Protease-Dead Separase Is Dominant Negative in the C. elegans Embryo

Separase is a protease that promotes chromosome segregation at anaphase by cleaving cohesin. Several non-proteolytic functions of separase have been identified in other organisms. We created a transgenic C. elegans line that expresses protease-dead separase in embryos to further characterize separase function. We find that expression of protease-dead separase is dominant-negative in C. elegans embryos, not previously reported in other systems. The C. elegans embryo is an ideal system to study developmental processes in a genetically tractable system. However, a major limitation is the lack of an inducible gene expression system for the embryo. We have developed two methods that allow for the propagation of lines carrying dominant-negative transgenes and have applied them to characterize expression of protease-dead separase in embryos. Using these methods, we show that protease-dead separase causes embryo lethality, and that protease-dead separase cannot rescue separase mutants. These data suggest that protease-dead separase interferes with endogenous separase function, possibly by binding substrates and protecting them from cleavage

Method and System for Identification of Metabolites Using Mass Spectra

A method and system is provided for mass spectrometry for identification of a specific elemental formula for an unknown compound which includes but is not limited to a metabolite. The method includes calculating a natural abundance probability (NAP) of a given isotopologue for isotopes of non-labelling elements of an unknown compound. Molecular fragments for a subset of isotopes identified using the NAP are created and sorted into a requisite cache data structure to be subsequently searched. Peaks from raw spectrum data from mass spectrometry for an unknown compound. Sample-specific peaks of the unknown com- pound from various spectral artifacts in ultra-high resolution Fourier transform mass spectra are separated. A set of possible isotope-resolved molecular formula (IMF) are created by iteratively searching the molecular fragment caches and combining with additional isotopes and then statistically filtering the results based on NAP and mass-to-charge (m/2) matching probabilities. An unknown compound is identified and its corresponding elemental molecular formula (EMF) from statistically-significant caches of isotopologues with compatible IMFs

Celebrity, Death, and Taxes: Michael Jackson\u27s Estate

The untimely death of Michael Jackson this past June presents an opportunity to reassess certain thorny estate tax issues that may arise when a celebrity dies owning valuable intellectual property. Elsewhere we have debated hypothetical, tax-motivated changes to state laws relating to postmortem publicity rights. This article focuses on existing legislation, like California’s, that makes publicity rights both devisable and descendible. Federal transfer taxes are levied on intangible property as well as tangible assets, and therefore apply to intellectual property, including a celebrity’s right of publicity and copyrights retained by an artist in his or her creations. Using Michael Jackson’s estate as an example, and focusing primarily on publicity rights, we examine two questions that any estate planner representing a celebrity client ought to consider. First, how should a personal representative value intellectual property for estate tax purposes? Second, what strategies are available to lessen the estate tax burden associated with certain intellectual property rights

Development and \u3cem\u3eIn Silico\u3c/em\u3e Evaluation of Large-Scale Metabolite Identification Methods Using Functional Group Detection for Metabolomics

Large-scale identification of metabolites is key to elucidating and modeling metabolism at the systems level. Advances in metabolomics technologies, particularly ultra-high resolution mass spectrometry (MS) enable comprehensive and rapid analysis of metabolites. However, a significant barrier to meaningful data interpretation is the identification of a wide range of metabolites including unknowns and the determination of their role(s) in various metabolic networks. Chemoselective (CS) probes to tag metabolite functional groups combined with high mass accuracy provide additional structural constraints for metabolite identification and quantification. We have developed a novel algorithm, Chemically Aware Substructure Search (CASS) that efficiently detects functional groups within existing metabolite databases, allowing for combined molecular formula and functional group (from CS tagging) queries to aid in metabolite identification without a priori knowledge. Analysis of the isomeric compounds in both Human Metabolome Database (HMDB) and KEGG Ligand demonstrated a high percentage of isomeric molecular formulae (43 and 28%, respectively), indicating the necessity for techniques such as CS-tagging. Furthermore, these two databases have only moderate overlap in molecular formulae. Thus, it is prudent to use multiple databases in metabolite assignment, since each major metabolite database represents different portions of metabolism within the biosphere. In silico analysis of various CS-tagging strategies under different conditions for adduct formation demonstrate that combined FT-MS derived molecular formulae and CS-tagging can uniquely identify up to 71% of KEGG and 37% of the combined KEGG/HMDB database vs. 41 and 17%, respectively without adduct formation. This difference between database isomer disambiguation highlights the strength of CS-tagging for non-lipid metabolite identification. However, unique identification of complex lipids still needs additional information

Taxes and Time Allocation: Evidence from Single Women

Hundreds of papers have investigated how incentives and policies affect hours worked in the market. This paper examines how income taxes affect time allocation in the other two-thirds of the day. Using the Panel Study of Income Dynamics from 1975 to 2004, we analyze the response of single women's housework, labor supply, and other time to variation in tax and transfer schedules across income levels, number of children, states, and time. We find that when the economic reward to participating in the labor force increases, market work increases and housework decreases, with the decrease in housework accounting for approximately two-thirds of the increase in market work. Analysis of repeated cross-sections of time diary data from 1975 to 2004 shows that changes in "home production" account for at least half of the increase in market hours of work in response to policy changes. Data on expenditures from the Consumer Expenditure Survey from 1980 to 2003 show some evidence that expenditures on market goods likely to substitute for housework increase in response to a greater incentive to join the labor force. The baseline estimates imply that the elasticity of substitution between consumption of home and market goods is 2.43. The results are consistent with the classic time allocation model of Becker (1965)

Taxes and Time Allocation: Evidence from Single Women

Hundreds of papers have investigated how incentives and policies affect hours worked in the market. This paper examines how income taxes affect time allocation in the other two-thirds of the day. Using the Panel Study of Income Dynamics from 1975 to 2004, we analyze the response of single women's housework, labor supply, and other time to variation in tax and transfer schedules across income levels, number of children, states, and time. We find that when the economic reward to participating in the labor force increases, market work increases and housework decreases, with the decrease in housework accounting for approximately two-thirds of the increase in market work. Analysis of repeated cross-sections of time diary data from 1975 to 2004 shows that changes in "home production" account for at least half of the increase in market hours of work in response to policy changes. Data on expenditures from the Consumer Expenditure Survey from 1980 to 2003 show some evidence that expenditures on market goods likely to substitute for housework increase in response to a greater incentive to join the labor force. The baseline estimates imply that the elasticity of substitution between consumption of home and market goods is 2.43. The results are consistent with the classic time allocation model of Becker (1965)