Electron beam seals outer surfaces of porous bodies

Porous tungsten plugs provide even airflow for frictionless bearings used in air bearing supported gyros. The plugs have their outer cylindrical surface sealed by an electron beam process to ensure unidirectional airflow through their exit ends

A Tight Upper Limit on Oscillations in the Ap star Epsilon Ursae Majoris from WIRE Photometry

Observations of Epsilon UMa obtained with the star tracker on the Wide Field Infrared Explorer (WIRE) satellite during a month in mid-2000 are analyzed. This is one of the most precise photometry of an Ap star. The amplitude spectrum is used to set an upper limit of 75 parts per million for the amplitude of stellar pulsations in this star unless it accidentally oscillates with a single mode at the satellite orbit, its harmonics or their one day aliases. This is the tightest limit put on the amplitude of oscillations in an Ap star. As the rotation period of Epsilon UMa is relatively short (5.1 d), it cannot be argued that the observations were made at a wrong rotational phase. Our results thus support the idea that some Ap stars do not pulsate at all.Comment: 4 pages, 4 figures, 2 style files, accepted for publication in ApJ

Pharmacokinetics of recombinant human erythropoietin applied subcutaneously to children with chronic renal failure

The single-dose pharmacokinetics of recombinant human erythropoietin (rHuEPO) given SC was investigated in 20 patients aged 7-20 years at different stages of chronic renal failure. In a pilot study we confirmed the lower bioavailability of the drug in 2 children when given SC compared with the IV route (24% and 43%, respectively). Following administration of 4,000 units/m2, rHuEPO SC effective serum erythropoietin concentrations increased from a mean baseline level (+/- SD) of 23 +/- 13 units/l to a mean peak concentration of 265 +/- 123 units/l, which was reached after 14.3 +/- 9.4 h, followed by a slow decline until baseline values were attained at 72 h. Mean residence time was 30 +/- 9 h and mean elimination half-time 14.3 +/- 7 h. The single-dose kinetics of SC rHuEPO in children with different degrees of renal failure are comparable to those in adult patients. Possibly, the higher efficacy of SC rHuEPO in patients with renal anaemia compared with IV rHuEPO is related to its prolonged action

Role of protein kinase C in inhibition of renin release caused by vasoconstrictors

It was the aim of the present study to get insight into some of the intracellular mechanisms by which the vasoconstrictor hormones angiotensin II (ANG II), arginine vasopressin (AVP), and norepinephrine (NE) inhibit renin release from renal juxtaglomerular cells. To this end a primary cell culture from rat renal cortex was established that consisted of 50% juxtaglomerular cells. The cultured juxtaglomerular cells contained prominent renin granules closely resembling those in the intact kidney and responded to a number of stimuli of renin release. By using these cultures, we found that ANG II (10(-7) M), AVP (10(-6) M), and NE (10(-5) M) inhibited renin release and increased the calcium permeability of the plasma membrane of the cultured cells. Both the effects on renin release and on calcium permeability could be diminished or even be abolished by the calcium channel blocker verapamil (Vp) (10(-5) M). ANG II, AVP, and NE led to an increased formation of diacylglycerol (DAG), a well-known stimulator of protein kinase C (PKC). Moreover, a direct stimulation of PKC by 12-O-tetradecanoylphorbol-13-acetate (TPA) (10(-8)-10(-6) M) also inhibited renin release and increased the calcium permeability of the cell membrane. Similar to ANG II, AVP, and NE, the effects of TPA on calcium permeability and renin release could be diminished by Vp. In conclusion, these results point toward a common mechanism by which vasoconstrictors inhibit renin release from renal juxtaglomerular cells: ANG II, AVP, and NE activate a phospholipase C, which generates DAG.(ABSTRACT TRUNCATED AT 250 WORDS

MOST observations of the roAp stars HD 9289, HD 99563, and HD 134214

We report on the analysis of high-precision space-based photometry of the roAp (rapidly oscillating Ap) stars HD 9289, HD 99563, and HD134214. All three stars were observed by the MOST satellite for more than 25 days, allowing unprecedented views of their pulsation. We find previously unknown candidate frequencies in all three stars. We establish the rotation period of HD 9289 (8.5 d) for the first time and show that the star is pulsating in two modes that show different mode geometries. We present a detailed analysis of HD 99563's mode multiplet and find a new candidate frequency which appears independent of the previously known mode. Finally, we report on 11 detected pulsation frequencies in HD 134214, 9 of which were never before detected in photometry, and 3 of which are completely new detections. Thanks to the unprecedentedly small frequency uncertainties, the p-mode spectrum of HD 134214 can be seen to have a well-defined large frequency spacing similar to the well-studied roAp star HD 24712 (HR 1217).Comment: 11 pages, 12 figures, accepted for publication in A&

Preliminary report on sand-streaming in Agadez and Tahoua Departments, Republic of Niger

There are no author-identified significant results in this report

A Unifying Theory for the Religion Clauses of the First Amendment

According to Justice Powell, the first amendment religion clauses are the source of some of the most perplexing questions that the Supreme Court confronts. In a long and rapidly expanding line of religion clause cases the Court has struggled, with a conspicuous lack of success, to articulate principles of broad applicability. The Court\u27s efforts to date have resulted in a jumble of tests, standards, and theoretical approaches from which predicting the outcome in future cases is very difficult. The conceptual problems that have frustrated the Court\u27s attempts at doctrinal development center in two broad areas: first,the meaning and effect of the establishment clause and second, the relationship between the establishment clause and the free exercise clause. In a third area, the meaning and effect of the free exercise clause, the Court has had somewhat less trouble articulating a doctrinal approach, but even here the Court has not applied the doctrine consistently and has not reached entirely predictable results. Perhaps the most telling measure of the Court\u27s doctrinal frustration in the religion clause area is the extent to which it recently has attempted to elevate its conspicuous lack of doctrinal consistency into an accepted methodology for decision making. Chief Justice Burger summarized current thinking on the relationship between the two religion clauses by noting that there is internal tension in the First Amendment between the Establishment Clause and the Free Exercise Clause. Finding a clearer acknowledgement of the Court\u27s failure to articulate a unifying theory underlying the two clauses would be difficult. Concerning the meaning and effect of the establishment clause, Chief Justice Burger has observed with apparent approval (or at least resignation) that the Court has been unwilling to tie establishment clause analysis to a single test. With the same apparent approval, Justice White has noted that our decisions have tended to avoid categorical imperatives and absolutist approaches .... This course sacrifices clarity and predictability for flexibility .. .., Describing the same phenomenon in another case, Justice O\u27Connor concluded that [e]very government practice must be judged in its unique circumstances to determine whether it constitutes an endorsement or disapproval of religion. In effect, the Court seems to have accepted the inevitability of an ad hoc approach with a final result in any case possible only after Supreme Court review... The thesis of this Article is that such a single overriding objective can be identified and articulated. This objective reflects the basic purpose of those who authored and adopted the religion clauses and, to a remarkable degree, harmonizes the Court\u27s apparently disparate results in religion clause cases. The Court\u27s conscious acceptance of the unifying theory proposed in this Article would provide a satisfying explanation for a large number of results arrived at by intuition in the past and would provide a theoretical basis from which to predict results in future cases

The Paradox Of Repression And Nonviolent Movements

Political repression often paradoxically fuels popular movements rather than undermining resistance. When authorities respond to strategic nonviolent action with intimidation, coercion, and violence, they often undercut their own legitimacy, precipitating significant reforms or even governmental overthrow. Brutal repression of a movement is often a turning point in its history: Bloody Sunday in the March to Selma led to the passage of civil rights legislation by the US Congress, and the Amritsar Massacre in India showed the world the injustice of the British Empire’s use of force in maintaining control over its colonies. Activists in a wide range of movements have engaged in nonviolent strategies of repression management that can raise the likelihood that repression will cost those who use it. The Paradox of Repression and Nonviolent Movements brings scholars and activists together to address multiple dimensions and significant cases of this phenomenon, including the relational nature of nonviolent struggle and the cultural terrain on which it takes place, the psychological costs for agents of repression, and the importance of participation, creativity, and overcoming fear, whether in the streets or online