Angular Correlations in the ß Decay of

We present the first measurement of the α-ß-ν angular correlation in the Gamow-Teller ß^{+} decay of ^{8}B. This was accomplished using the Beta-decay Paul Trap, expanding on our previous work on the ß^{-} decay of ^{8}Li. The ^{8}B result is consistent with the V-A electroweak interaction of the standard model and, on its own, provides a limit on the exotic right-handed tensor current relative to the axial-vector current of |C_{T}/C_{A}|^{2}<0.013 at the 95.5% confidence level. This represents the first high-precision angular correlation measurements in mirror decays and was made possible through the use of an ion trap. By combining this ^{8}B result with our previous ^{8}Li results, we demonstrate a new pathway for increased precision in searches for exotic currents.

Improved Limit on Tensor Currents in the Weak Interaction from

The electroweak interaction in the standard model is described by a pure vector-axial-vector structure, though any Lorentz-invariant component could contribute. In this Letter, we present the most precise measurement of tensor currents in the low-energy regime by examining the ß-ν[over ¯] correlation of trapped ^{8}Li ions with the Beta-decay Paul Trap. We find a_{ßν}=-0.3325±0.0013_{stat}±0.0019_{syst} at 1σ for the case of coupling to right-handed neutrinos (C_{T}=-C_{T}^{'}), which is consistent with the standard model prediction.

Impact of Modular Total Absorption Spectrometer measurements of ß decay of fission products on the decay heat and reactor ν[over ¯]_{e} flux calculation.

We report the results of a ß-decay study of fission products ^{86}Br, ^{89}Kr, ^{89}Rb, ^{90gs}Rb, ^{90m}Rb, ^{90}Kr, ^{92}Rb, ^{139}Xe, and ^{142}Cs performed with the Modular Total Absorption Spectrometer (MTAS) and on-line mass-separated ion beams. These radioactivities were assessed by the Nuclear Energy Agency as having high priority for decay heat analysis during a nuclear fuel cycle. We observe a substantial increase in ß feeding to high excited states in all daughter isotopes in comparison to earlier data. This increases the average γ-ray energy emitted by the decay of fission fragments during the first 10 000 s after fission of ^{235}U and ^{239}Pu by approximately 2% and 1%, respectively, improving agreement between results of calculations and direct observations. New MTAS results reduce the reference reactor ν[over ¯]_{e} flux used to analyze reactor ν[over ¯]_{e} interaction with detector matter. The reduction determined by the ab initio method for the four nuclear fuel components, ^{235}U, ^{238}U, ^{239}Pu, and ^{241}Pu, amounts to 0.976, 0.986, 0.983, and 0.984, respectively.

Evidence for Gamow-Teller Decay of

The ß-delayed neutron emission of ^{83,84}Ga isotopes was studied using the neutron time-of-flight technique. The measured neutron energy spectra showed emission from states at excitation energies high above the neutron separation energy and previously not observed in the ß decay of midmass nuclei. The large decay strength deduced from the observed intense neutron emission is a signature of Gamow-Teller transformation. This observation was interpreted as evidence for allowed ß decay to ^{78}Ni core-excited states in ^{83,84}Ge favored by shell effects. We developed shell model calculations in the proton fpg_{9/2} and neutron extended fpg_{9/2}+d_{5/2} valence space using realistic interactions that were used to understand measured ß-decay lifetimes. We conclude that enhanced, concentrated ß-decay strength for neutron-unbound states may be common for very neutron-rich nuclei. This leads to intense ß-delayed high-energy neutron and strong multineutron emission probabilities that in turn affect astrophysical nucleosynthesis models.

New half-lives of r-process Zn and Ga isotopes measured with electromagnetic separation.

The ß decays of neutron-rich nuclei near the doubly magic (78)Ni were studied at the Holifield Radioactive Ion Beam Facility using an electromagnetic isobar separator. The half-lives of (82)Zn (228±10 ms), (83)Zn (117±20 ms), and (85)Ga (93±7 ms) were determined for the first time. These half-lives were found to be very different from the predictions of the global model used in astrophysical simulations. A new calculation was developed using the density functional model, which properly reproduced the new experimental values. The robustness of the new model in the (78)Ni region allowed us to extrapolate data for more neutron-rich isotopes. The revised analysis of the rapid neutron capture process in low entropy environments with our new set of measured and calculated half-lives shows a significant redistribution of predicted isobaric abundances strengthening the yield of A>140 nuclei.

Orbital dependent nucleonic pairing in the lightest known isotopes of tin.

By studying the (109)Xe→(105)Te→(101)Sn superallowed α-decay chain, we observe low-lying states in (101)Sn, the one-neutron system outside doubly magic (100)Sn. We find that the spins of the ground state (J=7/2) and first excited state (J=5/2) in (101)Sn are reversed with respect to the traditional level ordering postulated for (103)Sn and the heavier tin isotopes. Through simple arguments and state-of-the-art shell-model calculations we explain this unexpected switch in terms of a transition from the single-particle regime to the collective mode in which orbital-dependent pairing correlations dominate.

Large beta-delayed neutron emission probabilities in the 78Ni region.

The beta-delayed neutron branching ratios (P{betan}) for nuclei near doubly magic 78Ni have been directly measured using a new method combining high-resolution mass separation, reacceleration, and digital beta-gamma spectroscopy of 238U fission products. The P{betan} values for the very neutron-rich isotopes ;{76-78}Cu and 83Ga were found to be much higher than previously reported and predicted. Revised calculations of the betan process, accounting for new mass measurements and an inversion of the pi2p{3/2} and pi1f{5/2} orbitals, are in better agreement with these new experimental results.

Parental socialization of children's dysregulated expression of emotion and externalizing problems.

The relations of parents' warmth, emotional expressivity, and discussion of emotion to 2nd-5th graders' regulation of emotional expressivity, externalizing problem behaviors, and expressivity were examined. Parents' and children's facial expressions to evocative slides were observed, as was parents' discussion of the slides, and parents and teachers provided information on children's regulation of expressivity and problem behavior. Analyses supported the hypothesis that the effect of parental variables on children's problem behavior was at least partly indirect through their children's regulation of emotion. Children's low negative (versus positive) facial expressivity to negative slides was associated with problem behavior for boys. A reversed model did not support the possibility that children's functioning had causal effects on parenting. The findings suggest that parents' emotion-related behaviors are linked to children's regulation of expressivity and externalizing behaviors.

Benner and the critics: promoting scholarly dialogue.

The research and theorizing of Patricia Benner and colleagues have been very influential in nursing around the world. In recent years, however, her work has been challenged on both methodological and philosophical grounds, primarily from critical-hermeneutic and postmodernist perspectives. Critics have identified concerns about Benner's work, including sample limitations, decontextualized exemplars, the exclusion of social and political concerns, the problematic issues of experience and interpretation, and the unacknowledged position of the researcher. This article attempts to synthesize those critiques, and offers a comprehensive framework for constructive dialogue. Disciplinary maturity and scholarly integrity require critical reevaluation of influential texts and research programs.

Hematometra secondary to anticoagulant rodenticide toxicity.

An adult, intact female Australian shepherd presented for frank vaginal bleeding of unknown duration. The only coagulation profile abnormality upon presentation was mild prolongation of the partial thromboplastin time (PTT). The uterus was removed at surgery and contained a large amount of coagulated blood. Clotting profiles were markedly abnormal 48 hours postoperatively. Serum analysis was positive for brodifacoum, an anticoagulant rodenticide. Preoperative coagulation was most likely normalized by vitamin K1 therapy administered prior to presentation. The only manifestation of anticoagulant rodenticide was hematometra. Rodenticide intoxication should be considered in the differential diagnosis list of hematometra or metrorrhagia.

Dilemmas of caring in a corporate context: a critique of nursing case management.

Nursing case management is widely acclaimed within the nursing literature as a form of advanced practice, beneficial for both clients and payers. However, case management programs involve potential conflicts between client goals and system goals, especially in relation to for-profit managed care systems. Early nursing discourse tended to minimize those conflicts, but more recent literature has begun to address role conflicts and ethical challenges. Feminist and critical-theory perspectives are used to examine nursing case management in the contexts of capitalism and sexism, thereby illuminating recurrent dilemmas within the profession. The ability of nursing case management to resolve those dilemmas is questioned.

Efficacy of parathyroid gland autotransplantation in maintaining serum calcium concentrations after bilateral thyroparathyroidectomy in cats.

Bilateral thyroidectomy is a commonly indicated treatment for feline hyperthyroidism. The most common postoperative complication is hypocalcemia due to disruption of the parathyroid glands. When parathyroid gland disruption is obvious, many authors suggest autotransplantation (AT) of the glands. This technique never has been supported by a scientific study which monitored postoperative calcium or parathyroid hormone (PTH) concentrations. Cats in this study each underwent bilateral thyroidectomy and parathyroid AT to mimic a clinical situation. Serum calcium concentrations normalized much quicker than concentrations in previously reported cats undergoing bilateral thyroidectomy and parathyroidectomy. Parathyroid AT greatly reduces morbidity in the parathyroidectomized cat.

Gingival vascular hamartoma with associated paraneoplastic hyperglycemia in a kitten.

A 4-month-old domestic shorthair cat was examined because of a maxillary gingival mass that had regrown following excisional biopsy. The kitten also had a history of persistently high blood glucose concentrations, despite 2 weeks of insulin treatment. Radiography revealed maxillary alveolar bone lysis and displacement of multiple teeth. Partial maxillectomy was performed to remove the mass, which histologically was a gingival vascular hamartoma. Hyperglycemia permanently resolved < 24 hours after mass removal. On the basis of the temporal relationship between mass removal and resolution of hyperglycemia, as well as the lack of evidence of any concurrent disease, hyperglycemia in this cat was considered to be a paraneoplastic syndrome.

Prognostic factors in dogs with osteosarcomas of the flat or irregular bones.

The medical records of 45 dogs with histopathologically confirmed osteosarcomas arising from flat or irregular bones were reviewed. Thirty-five percent of the dogs eventually developed metastases. Telangectatic tumors and tumors arising from the rib and scapula had the highest prevalence of metastases. Survival times were short, with an overall median survival time of 120 days. Anatomic site, body weight, and completeness of surgical excision were found to be prognostic factors. Dogs with mandibular osteosarcomas in this study had shorter survival times than those times recently reported. 21 Local recurrence was the most common cause of death or euthanasia in this population of dogs.

Family resemblances in height and relative weight in the Framingham Heart Study.

The correlations of both height and relative weight (the Quetelet Index: wt/ht2) were studied amongst adult relatives in the Framingham Heart Study. The parental generation was first examined starting in 1949 when they were aged 30-62 years. The offspring (and their spouses) were examined beginning in 1971 when they were aged 20-49 years. Thus, it was possible to compare adult levels of body size in two generations. For height there are correlations between relatives that suggest large genetic variation for adult body height. For relative weight as measured by Quetelet's Index, the associations between relatives show a pattern that is more difficult to interpret and gives little support for sizable contributions of genetic differences to the population variation in relative weight. Although there is little evidence for large genetic variation for obesity, there is marked resemblance for obesity among first-degree relatives. This fact may be used to advance the family-based approach to screening, identification and intervention on the cardiovascular complications of obesity.

Evidence for additional blood pressure correlates in adults 20-56 years old.

The offspring of parents belonging to the original Framingham Heart Study cohort, and spouses of these offspring, were examined beginning in 1971. Cardiovascular examinations similar to those performed on the parents in 1952-1953 were given to offspring and their spouses. The mean blood pressure (BP) appeared to be lower in the female offspring-spouses than in the cohort mothers. Comparable multivariate analyses on 3588 offspring and spouses of both sexes, ages 20-49 years, and 1842 parents, ages 30-49 years, confirmed the frequently reported importance of weight, heart rate, alcohol consumption, glucose and hematocrit or hemoglobin as independent positive correlates and smoking as an inverse correlate of botsured variables of total serum proteins and plasma triglycerides added significantly to prediction of BP in both sex groups, and a less striking negative association was found for serum phosphorus. The findings for serum proteins and triglycerides were supported in a separate population of middle-aged twin men. Even with the additional measured variables, only 28-34% of the total BP variance is explained in these populations.

The association of total cholesterol, triglycerides and plasma lipoprotein cholesterol levels in first degree relatives and spouse pairs.

HDL, VLDL, and LDL cholesterol as well as total cholesterol were measured in young adult offspring of Framingham Heart Study participants. Parental total cholesterol levels measured in the early 1950s were found to be significant predictors of present total cholesterol in the offspring. While both maternal and paternal cholesterol levels made an independent contribution to the prediction of the offspring's cholesterol, the mother's contribution was significantly greater than the father's for male offspring with a similar but less striking relationship for female offspring. The correlation for LDL cholesterol levels for siblings was higher than for HDL cholesterol or log VLDL choles terol. When adjustments were made for age, body weight, alcohol intake and cigarette smoking, slight reductions in the correlations were noted, but all adjusted correlations remained significantly different from zero. The spouse correlations for lipoproteins, however, did not differ from zero after adujustment. Since the significant association for lipoproteins in spouse pairs disappears on adjustment for correlates but the association for siblings does not, it is likely that the sibling lipoprotein associations result from either genetic or environmental factors shared early in life.

Cigarette smoking and HDL cholesterol: the Framingham offspring study.

High density lipoproteins were measured on fasting blood samples from 4107 men and women. Control for reported alcohol consumption and subscapular skinfold thickness using multiple regression analysis allowed an examination of the relationship between cigarette smoking and HDL cholesterol. Cigarette smoking was found to be associated with an average difference in HDL cholesterol of about 4 mg/dl in men and 6 mg/dl in women. Furthermore, when heavy alcohol drinkers were eliminated a significant negative association between number of cigarettes smoked and HDL cholesterol was demonstrable in both men and women. There was no evidence that former cigarette smokers, with the exception of those who switched to cigars or pipes or had quit less than one year, had lower HDL levels. Cigar or pipe smokers who had never smoked cigarettes had alcohol- and skinfold-adjusted HDL cholesterol comparable to the non-smoker. These observations indicate another possible link between inhaled tobacco smoke and the atherosclerotic process and suggest the need for further studies and experiments that might clarify the mutual relationship of HDL cholesterol, cigarette smoking and the atherosclerotic process.