Novel Approach to ^{93m}Mo Isomer Depletion: Nuclear Excitation by Electron Capture in Resonant Transfer Process

A novel approach for isomer depletion in ion-atom collisions is proposed and considered theoretically. Analyses are performed for the depletion of the ^{93m}Mo isomer for which an unexpectedly large probability was measured in the beam-based experiment of Chiara et al. [Nature (London) 554, 216 (2018)NATUAS0028-083610.1038/nature25483]. The subsequent attempt at a theoretical description based on state-of-the-art atomic theory did not reproduce the experimental result [Wu et al., Phys. Rev. Lett. 122, 212501 (2019)PRLTAO0031-900710.1103/PhysRevLett.122.212501] and showed a dramatic disagreement with the experiment (by many orders of magnitude). This conflict calls for further research on the nature of isomer depletion mechanisms occurring in atomic processes. Here, we propose to consider the ^{93m}Mo isomer depletion as the nuclear excitation by electron capture in resonant transfer process taking into account the momentum distribution of the target electrons. Although our results only slightly shift the upper theoretical limit for the total ^{93m}Mo isomer depletion probability toward the experimental value, they show the importance of considering the Compton profile in the theoretical description, in particular for the L shell, for which the depletion probability increases by many orders of magnitude.

Direct observation of long-lived isomers in 212Bi

Long-lived isomers in (212)Bi have been studied following (238)U projectile fragmentation at 670 MeV per nucleon. The fragmentation products were injected as highly charged ions into a storage ring, giving access to masses and half-lives. While the excitation energy of the first isomer of (212)Bi was confirmed, the second isomer was observed at 1478(30) keV, in contrast to the previously accepted value of >1910 keV. It was also found to have an extended Lorentz-corrected in-ring half-life >30 min, compared to 7.0(3) min for the neutral atom. Both the energy and half-life differences can be understood as being due a substantial, though previously unrecognized, internal decay branch for neutral atoms. Earlier shell-model calculations are now found to give good agreement with the isomer excitation energy. Furthermore, these and new calculations predict the existence of states at slightly higher energy that could facilitate isomer deexcitation studies.

≃10 eV ionization shift in Ir Kα2 from a near-coincident Lu K-edge

Close to an x-ray filter's K-edge the transmission depends strongly on the photon energy. For a few atom pairs, the K-edge of one is only a few tens of eV higher than a K-line energy of another, so that a small change in the line's energy becomes a measurable change in intensity behind such a matching filter. Lutetium's K-edge is ≃27 eV above iridium's Kα(2) line, ≃63.287 keV for cold Ir. A Lu filter reduces this line's intensity by ≃10 % when it is emitted by a plasma, indicating an ionization shift Δε≃10±1 eV.

Discovery of highly excited long-lived isomers in neutron-rich hafnium and tantalum isotopes through direct mass measurements

A study of cooled ¹⁹⁷Au projectile-fragmentation products has been performed with a storage ring. This has enabled metastable nuclear excitations with energies up to 3 MeV, and half-lives extending to minutes or longer, to be identified in the neutron-rich nuclides ¹⁸³(,)¹⁸⁴(,)¹⁸⁶Hf and ¹⁸⁶(,)¹⁸⁷Ta. The results support the prediction of a strongly favored isomer region near neutron number 116.

Schottky mass measurement of the 208Hg isotope: implication for the proton-neutron interaction strength around doubly magic 208Pb

Time-resolved Schottky mass spectrometry has been applied to uranium projectile fragments which yielded the mass value for the 208Hg (Z=80, N=128) isotope. The mass excess value of ME=-13 265(31) keV has been obtained, which has been used to determine the proton-neutron interaction strength in 210Pb, as a double difference of atomic masses. The results show a dramatic variation of the strength for lead isotopes when crossing the N=126 neutron shell closure, thus confirming the empirical predictions that this interaction strength is sensitive to the overlap of the wave functions of the last valence neutrons and protons.

Megavoltage bremsstrahlung end point voltage diagnostic

In a material, a beam of x rays is accompanied by various kinds of secondary radiation, including Compton electrons from collisions between the x rays and the material's electrons. For megavoltage bremsstrahlung in air, many of these Compton electrons are forward-directed and fast enough to be deflected outside the beam's edge by a magnetic field perpendicular to the beam. At the beam's edge, the dose from the deflected Compton electrons has a pattern that depends on the radiation's end point energy. Dose patterns measured with radiochromic film on a nominally 1 and 2 MV linear accelerator agree reasonably well with the corresponding Monte Carlo computations. With further development, the dose pattern produced outside the beam by such a sweeper magnet could become a noninvasive way to monitor megavoltage bremsstrahlung, when the end point energies are difficult to determine with other methods.

Criterion-related validity of the Marital Disaffection Scale as a measure of marital estrangement

The Marital Disaffection Scale was administered, along with measures of positive feelings towards spouse, problem-drinking behavior of spouse, workaholic behavior of spouse, and marital status, to 323 female members of the American Counseling Association. Scores on the Marital Disaffection Scale showed significant inverse correlations (r = -.94) with positive feelings towards spouse and (rpb = -.63) with marital status. Scores on the Marital Disaffection Scale showed significant positive relationships (r = .36) with spouse's problem drinking behavior and (r = .48) with workaholic behavior of spouse. The results support the use of the Marital Disaffection Scale as a measure of emotional estrangement in marriage.

Assessing the offspring of workaholic parents: the Children of Workaholics Screening Test

This study reports initial stages in the development of a self-report instrument that measures offsprings' mental disposition toward their parents' work habits. In an initial sitting, a battery of tests was administered to 207 young adults to assess the reliability and validity of the Children of Workaholics Screening Test. After a 2-wk. interval, the test was administered again. Test-retest reliability, split-half reliability, and concurrent validity are reported. The findings provide strong support for the utility of the Children of Workaholics Screening Test for assessing the offspring of workaholic parents.

Counseling students' attribution of diagnostic credibility to clinical supervisors

Research on factors influencing diagnostic credibility has not been widespread. In this study, agreement ratings for a clinical diagnosis were compared for two groups of students receiving supervision from differently credentialed hypothetical supervisors. Implications of these findings are discussed relative to preparation practices and improving clinical practice. As 190 students who had completed either less than one-half (n = 112) or more than one-half (n = 78) of their programs in 9 institutions gave mean ratings of about 5 on a 10-point scale, they did not differentially rate diagnostic credibility of the hypothetical supervisors having credentials as psychiatrists, doctorate-holding counselor education faculty, doctorate-holding psychologists, and doctoral students holding master's degrees in counselor education.

Relationships of ozone exposure to pine injury in the Sierra Nevada and San Bernardino Mountains of California, USA

Hourly ambient ozone exposure data and crown injury measurements were gathered in the Sierra Nevada and San Bernardino Mountains of California to develop relationships between the Ozone Injury Index (OII), the Forest Pest Management Index (FPM), chlorotic mottle, fascicle retention (OII index components) and cumulative ambient ozone indices for Pinus ponderosa Dougl. ex Laws and Pinus jeffreyi Grev. and Balf. Eleven sites located in the mixed conifer forest near ambient ozone monitoring sites were evaluated annually for 4 years. Four other sites in the San Bernardino Mountains were evaluated for 1 year. Analyses showed OII to be functionally equivalent (r2 = 0.96) to the FPM, and to depend only on fascicle retention and chlorotic mottle (R2 = 0.95) of the fourth whorl (or if four whorls are not present at the site, then the last whorl present for the majority of trees). Significant associations were found between OII and 4-year 24-h. summer SUM0, SUM06, W126 and HRS80 ozone indices. Three sites had higher levels of cumulative chlorotic mottle for individual whorls and larger numbers of trees with visible crown injury than other sites with similar cumulative ambient ozone levels. Including an indicator variable to discriminate between these two groups of sites increased R2 and decreased root mean square (RMSE) for all indices, especially SUM0 (R2 = 0.93, RMSE reduced by 46%).

Impact of biotechnology on the diagnostics of thrombotic disorders

The use of monoclonal antibodies, genetic engineering, and recombinant molecules have greatly affected the diagnostics and therapeutics of thrombotic disorders. Future diagnostics and therapeutics will use chimeric or bifunctional antibodies, DNA probes, and perhaps liposomes in order to improve sensitivity and therapeutic efficacy. These highly sensitive and specific immunochemical tools also allow us to quantitate the activities of the various steps of the hemostatic mechanism in vivo at subnamolar levels.

Giant cell arteritis of the breast

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Simulating the loss of PIP: what can hospitals expect?

With the loss of the periodic interim payment (PIP), hospitals will lose the steady flow of income they have become dependent upon. However, with the use of computer simulation, hospital administrators can see how this loss could possibly affect their institutions.

Spreadsheets simplify sensitivity analysis for capital decisions

The availability and ease of use of electronic spreadsheets removes the previously cumbersome number crunching burden of sensitivity analysis. In this article, the advantages of sensitivity analysis will be reintroduced and a model will be presented using a pro forma statement for a freestanding magnetic resonance imaging center.

Inflation, risk, replacement, closure: concerns in capital budgeting

Four problems can affect the capital budgeting process-inflation, replacement, risk, and closure. Therefore financial managers must consider these problems carefully when making capital budgeting decisions. This article is the second of a two-part series on capital budgeting in health care. It builds on the existing level of knowledge of capital budgeting to give the financial manager confidence in the use of capital budgeting techniques.

NPV vs. IRR: with capital budgeting, which do you choose?

The standard that defines quality health care rises as new technologies and procedures become available. To the health care financial manager, maintaining quality health care becomes a twofold problem--how to keep up with the latest developments while staying within budget guidelines. Two methods of analyzing capital expenditures are available to the financial manager, IRR and NPV. The latter is the safest and most reliable. NPV takes into account present market conditions and neither penalizes nor overly rewards either the buyer or seller of a particular project. This article is the first of a two-part series on capital budgeting in health care and takes the financial manager beyond the pure arithmetic of NPV and IRR to show the depth and meaning behind the arithmetic.

Organoastatine chemistry. Astatination via electrophilic destannylation

Substantial interest is currently focused on the alpha-emitting radiohalogen 211At, principally because of its potential use in the radiation therapy of cancer. Knowledge of organoastatine chemistry is incomplete and existing methods for its incorporation restrict the range of compounds which may be labeled. Aryl and vinyl Sn(IV) compounds are notably susceptible to substitution of tin by a variety of electrophiles. We have investigated the reaction of aryltrialkylstannanes with astatine and report here the first examples of astatodestannylation. Formation of aryl astatides proceeds rapidly, cleanly and under mild conditions. The data further elucidate aspects of astatine reactivity and suggest a general route to synthesize astatinated compounds.

On the transport of nematodes by the wind

The possible effectiveness of atmospheric transport of nematode forms (dry larvae or eggs) as a means for introducing new species to a given environment is examined. Given the measured sedimentation velocities for a range of forms (0.1 >/= Ws >/= 0.6 mps), the necessary conditions on the wind speed required for natural erosion are defined. With these results scenarios for lofting, transport, and diffusion of these forms are examined using relevant gaussian plume models. Results indicate that on rare occasions individuals can be deposited up to 40 km from their original location. Redepositions up to 5 km per erosion event should be fairly common occurances when dry loose soil conditions or dry tillage operations combine with optimal atmospheric conditions and the presence of significant numbers of nematodes at the surface.

Manual ellipsometry made semiautomatic

A simple, inexpensive mechanical device is described that was designed to provide more effective data acquisition and to fit onto an already existing polarizer wheel drive mechanism of a commercially available, manual ellipsometer. A gas/metal adsorption experiment is used to illustrate typical results. Use procedures are detailed.

Management of pheochromocytoma during pregnancy

To reduce the high maternal and fetal mortality in pheochromocytoma of pregnancy, therapy is advocated with phenoxybenzamine and propranolol to obtain adequate alpha- and beta-adrenergic receptor blockade. In early pregnancy control of symptoms may be difficult, but the patient may be carried to term with such medical therapy. Delivery should be by cesarean section before the onset of labour, with, if possible, simultaneous removal of the tumour. Additional preoperative preparation with phenoxybenzamine and propranolol and careful intraoperative management are essential. During her third pregnancy a 29-year-old woman was found to have a pheochromocytoma of the left adrenal gland. After the medical therapy and preparation described, the infant was delivered by cesarean section and the mother's left adrenal gland excised. Eight-year follow-up, including during a fourth pregnancy, showed no recurrence of tumour in the mother and only mild hypertension. The infant developed normally.