By-Products of Prosperity: Transborder Hazardous Waste Issues Confronting the Maquiladora Industry

The maquiladora program allows Mexican laborers to work in American factories operating in Mexico. This program was specifically designed to generate employment and stimulate industry in Mexico. After a brief discussion of the current status and significance of the maquiladora industry, this Article explains the procedures for the transborder shipment of hazardous waste from Mexico to the United States, a hallmark of the maquiladora program. The authors analyze these procedures in light of anticipated regulatory and economic trends in the region. The analysis includes a discussion of the issue of commingled waste, as well as how NAFTA (North American Free Trade Agreement) will impact Mexico\u27s environmental policies. The authors conclude that the maquiladora program has a prosperous future, despite the hazardous waste issues that threaten the health of the industry

Resolving Coparenting Dissatisfaction In Couples: A Preliminary Task Analysis Study.

This study explored the change that unfolded when parents resolved their coparenting dissatisfaction during an Integrative Brief Systemic Intervention (IBSI) for parent couples. We conducted a task analysis (Greenberg, 2007) to build a model of resolving coparenting dissatisfaction. We compared a postulated model of change (rational model) based on theoretical and clinical assumptions to the observations of the actual change process that couples experienced in an IBSI (empirical analysis). The empirical analysis was conducted on six IBSI therapy cases (three exhibiting positive development and three exhibiting no development). We defined positive development in IBSI as moving from coparenting dissatisfaction to coparenting satisfaction. The final rational-empirical model included six steps that facilitated the resolution of coparenting dissatisfaction. This study contributes to deepening the knowledge of how coparenting may change during marital therapy

Increased Sensitivity to Possible Muonium to Antimuonium Conversion

A new experimental search for muonium-antimuonium conversion was conducted at the Paul Scherrer Institute, Villigen, Switzerland. The preliminary analysis yielded one event fulfilling all required criteria at an expected background of 1.7(2) events due to accidental coincidences. An upper limit for the conversion probability in 0.1 T magnetic field is extracted as $8 \cdot 10^{-11}$ (90% CL).Comment: 2 figure

Hyperfine Structure of S-States in Muonic Helium Ion

Corrections of orders alpha^5 and alpha^6 are calculated in the hyperfine splittings of 1S and 2S - energy levels in the ion of muonic helium. The electron vacuum polarization effects, the nuclear structure corrections and recoil corrections are taken into account. The obtained numerical values of the hyperfine splittings -1334.56 meV (1S state), -166.62 meV (2S state) can be considered as a reliable estimate for the comparison with the future experimental data. The hyperfine splitting interval Delta_{12}=(8 Delta E^{hfs}(2S)- Delta E^{hfs}(1S)) = 1.64 meV can be used for the check of quantum electrodynamics.Comment: 14 pages, 5 figure

Atomic parity nonconservation and neutron radii in cesium isotopes

The interpretation of future precise experiments on atomic parity violation in terms of parameters of the Standard Model could be hampered by uncertainties in the atomic and nuclear structure. While the former can be overcome by measurement in a series of isotopes, the nuclear structure requires knowledge of the neutron density. We use the nuclear Hartree-Fock method, which includes deformation effects, to calculate the proton and neutron densities in {125}Cs-{139}Cs. We argue that the good agreement with the experimental charge radii, binding energies, and ground state spins signifies that the phenomenological nuclear force and the method of calculation that we use is adequate. Based on this agreement, and on calculations involving different effective interactions, we estimate the uncertainties in the differences of the neutron radii delta_{N,N'} and conclude that they cause uncertainties in the ratio of weak charges, the quantities determined in the atomic parity nonconservation experiments, of less than 10^{-3}. Such an uncertainty is smaller than the anticipated experimental error.Comment: 24 pages (RevTeX) 4 figures (Postscript/uuencoded compressed) Caltech Preprint No. MAP-153 (March 1993

Solution of the Nuclear Shell Model by Symmetry-Dictated Truncation

The dynamical symmetries of the Fermion Dynamical Symmetry Model are used as a principle of truncation for the spherical shell model. Utilizing the usual principle of energy-dictated truncation to select a valence space, and symmetry-dictated truncation to select a collective subspace of that valence space, we are able to reduce the full shell model space to one of manageable dimensions with modern supercomputers, even for the heaviest nuclei. The resulting shell model then consists of diagonalizing an effective Hamiltonian within the restricted subspace. This theory is not confined to any symmetry limits, and represents a full solution of the original shell model if the appropriate effective interaction of the truncated space can be determined. As a first step in constructing that interaction, we present an empirical determination of its matrix elements for the collective subspace with no broken pairs in a representative set of nuclei with $130\le A \le 250$. We demonstrate that this effective interaction can be parameterized in terms of a few quantities varying slowly with particle number, and is capable of describing a broad range of low-energy observables for these nuclei. Finally we give a brief discussion of extending these methods to include a single broken collective pair.Comment: invited paper for J. Phys. G, 57 pages, Latex, 18 figures a macro are available under request at [email protected]

Search for the lepton-family-number nonconserving decay \mu -> e + \gamma

The MEGA experiment, which searched for the muon- and electron-number violating decay \mu -> e + \gamma, is described. The spectrometer system, the calibrations, the data taking procedures, the data analysis, and the sensitivity of the experiment are discussed. The most stringent upper limit on the branching ratio of \mu -> e + \gamma) < 1.2 x 10^{-11} was obtained

Transcriptome Profiling of Bovine Milk Oligosaccharide Metabolism Genes Using RNA-Sequencing

This study examines the genes coding for enzymes involved in bovine milk oligosaccharide metabolism by comparing the oligosaccharide profiles with the expressions of glycosylation-related genes. Fresh milk samples (n = 32) were collected from four Holstein and Jersey cows at days 1, 15, 90 and 250 of lactation and free milk oligosaccharide profiles were analyzed. RNA was extracted from milk somatic cells at days 15 and 250 of lactation (n = 12) and gene expression analysis was conducted by RNA-Sequencing. A list was created of 121 glycosylation-related genes involved in oligosaccharide metabolism pathways in bovine by analyzing the oligosaccharide profiles and performing an extensive literature search. No significant differences were observed in either oligosaccharide profiles or expressions of glycosylation-related genes between Holstein and Jersey cows. The highest concentrations of free oligosaccharides were observed in the colostrum samples and a sharp decrease was observed in the concentration of free oligosaccharides on day 15, followed by progressive decrease on days 90 and 250. Ninety-two glycosylation-related genes were expressed in milk somatic cells. Most of these genes exhibited higher expression in day 250 samples indicating increases in net glycosylation-related metabolism in spite of decreases in free milk oligosaccharides in late lactation milk. Even though fucosylated free oligosaccharides were not identified, gene expression indicated the likely presence of fucosylated oligosaccharides in bovine milk. Fucosidase genes were expressed in milk and a possible explanation for not detecting fucosylated free oligosaccharides is the degradation of large fucosylated free oligosaccharides by the fucosidases. Detailed characterization of enzymes encoded by the 92 glycosylation-related genes identified in this study will provide the basic knowledge for metabolic network analysis of oligosaccharides in mammalian milk. These candidate genes will guide the design of a targeted breeding strategy to optimize the content of beneficial oligosaccharides in bovine milk