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Development of the sciences of bac teriology and virology during the late nineteenth and early twentieth cen turies and parallel advances in clinical medicine and epidemiology provided the necessary tools to attribute 555 known outbreaks of waterborne dis ease, in the United States alone, to public and private water supplies dur ing the period 1938 to 1960 (1) (2). These 555 outbreaks involved a total of 137,304 known cases. Studies re vealed that only 35 to 50 percent of the outbreaks in New York State had been reported to the National Office of Vital Statistics during the study pe riods. This lack of reporting out breaks of disease in New York could well reflect the effort of all state health
A female patient is described with von Recklinghausen neurofibromatosis (NF1) in association with a balanced translocation between chromosome 17 and 22 [46,XX,t(17;22)(q11.2;q11.2)]. The breakpoint in chromosome 17 is cytogenetically identical to a previously reported case of NF1 associated with a 1;17 balanced translocation and suggests that the translocation events disrupt the NF1 gene. This precisely maps the NF1 gene to 17q11.2 and provides a physical reference point for strategies to clone the breakpoint and therefore the NF1 gene. A human-mouse somatic cell hybrid was constructed from patient lymphoblasts which retained the derivative chromosome 22 (22pter----22q11.2::17q11.2----17qter) but not the derivative 17q or normal 17. Southern blot analysis with genes and anonymous probes known to be in proximal 17q showed ErbA1, ErbB2, and granulocyte colony-stimulating factor (CSF3) to be present in the hybrid and therefore distal to the breakpoint, while pHHH202 (D17S33) and beta crystallin (CRYB1) were absent in the hybrid and therefore proximal to the breakpoint. The gene cluster including ErbA1 is known to be flanked by the constitutional 15;17 translocation breakpoint in hybrid SP3 and by the acute promyelocytic leukemia (APL) breakpoint, which provides the following gene and breakpoint order: cen-SP3-(D17S33,CRYB1)-NF1-(CSF3,ERBA1, ERBB2)-APL-tel. The flanking breakpoints of SP3 and API are therefore useful for rapidly localizing new markers to the neurofibromatosis critical region, while the breakpoints of the two translocation patients provide unique opportunities for reverse genetic strategies to clone the NF1 gene.
Empirical evidence for the involvement of nonradial pulsations (NRP's) in the mass loss from Be stars ranges from (i) a singular case (\object{$μ$ Cen}) of repetitive mass ejections triggered by multi-mode beating to (ii) several photometric reports about enormous numbers of pulsation modes popping up during outbursts and on to (iii) effective single-mode pulsators. The BRITE Constellation of nanosatellites was used to obtain mmag photometry of the Be stars $η$ and \object{$μ$ Cen}. In the low-inclination star \object{$μ$ Cen}, light pollution by variable amounts of near-stellar matter prevented any new insights into the variability and other properties of the central star. In the equator-on star \object{$η$ Cen}, BRITE photometry and {\sc Heros} echelle spectroscopy from the 1990s reveal an intricate clockwork of star-disk interactions. The mass transfer is modulated with the frequency difference of two NRP modes and an amplitude three times as large as the amplitude sum of the two NRP modes. This process feeds a high-amplitude circumstellar activity running with the incoherent and slightly lower so-called Štefl frequency. The mass loss-modulation cycles are tightly coupled to variations in the value of the Štefl frequency and in its amplitude, albeit with strongly drifting phase differences. The observations are well described by the decomposition of the mass loss into a pulsation-related engine in the star and a viscosity-dominated engine in the circumstellar disk. Arguments are developed that large-scale gas-circulation flows occur at the interface. The propagation rates of these eddies manifest themselves as Štefl frequencies. Bursts in power spectra during mass-loss events can be understood as the noise inherent to these gas flows.
Abstract Intermediate-mass black holes (IMBHs) have been alternatively predicted to be quite common in the centres of globular clusters or nearly impossible to form and retain in the centres of globular clusters. As it has been recently shown that radio observations are currently the most sensitive observational technique for detecting such objects, we have obtained new deep radio observations of Omega Cen, and have reanalyzed older observations of M 15 in the hope of constraining the masses of possible black holes in their centres. In both cases, upper limits of about 100 μJy are found at GHz frequencies. We find that if the Bondi–Hoyle accretion rate truly represents the spherical accretion rate onto a black hole, then the masses of the black holes in the centres of these two galaxies are severely constrained – with mass limits of less than about 100 solar masses in both cases. If more realistic assumptions are made based on recent work showing the Bondi rate to be a severe overestimate, then the data for Omega Cen are marginally consistent with a black hole of about 1/1000 of the mass of the cluster (i.e. about 1000 M⊙). The data for M 15 are then only marginally consistent with previous reports of a ~2000 solar mass black hole, and we note that there is considerable hope for either detecting the black hole or improving this upper limit with current instrumentation. Finally, we discuss the possibility that the radio source near the core of the Ursa Minor dwarf spheroidal galaxy is a ~104-M⊙ black hole.
This report describes two patients with a distinctive type of dicentric autosomal chromosome formed by breakage and union between homologous chromosomes. These stable chromosomes possess two C bands, implying the presence of two centromeric regions. The first child, evaluated for dysmorphic features was shown to have an abnormal chromosome 16, designated as 46, XX, -16, + dic (16) (pter leads to cen leads to q22::p11 leads to qter). The second case is a child with the typical features of trisomy 18 whose karyotype is designated as 46, XX, -18, + dic (18) (qter leads to p11.1 :: p11.3 leads to cen leads to qter). The stability of these chromosomes is presumably in result of centromere suppression and associated premature centromere division of the suppressed centromere. The possible mechanism of formation of these homodicentric chromosomes is presented, and a comparison is made between them and three patients with dicentric X chromosomes.
Abstract Mutual recognition (MR) is rightly applauded as an ingenious innovation. Nevertheless, it is very demanding in actual practice. The article addresses the pros and cons of MR in EU goods markets and seeks to find effective remedies to be applied by the authorities and, to some extent, by business. MR is a demanding form of ‘governance’. Not only should judicial MR be distinguished from regulatory MR, but MR is best understood when placed in a context of alternative ways of accomplishing free movement in the internal market. A critical distinction in the regime consists in the way existing barriers to free movement are tackled as against potential barriers caused by new legislation in member states. At the same time MR is associated with many substantial benefits and costs, in particular for judicial MR. The article explores several routes which would result in more and better MR. Keywords: Free movementgovernanceharmonizationmutual recognitionrisk regulation ACKNOWLEDGEMENTS I would like to thank Susanne Schmidt for her helpful comments on earlier drafts of this article. Notes 1 For more elaborate treatment, see the contributions by, respectively, Mattera, Weiler and Pelkmans in Kostoris Padoa Schioppa Citation(2005), all mainly referring to goods markets. See also Pelkmans et al. Citation(2000). 2 The notion of SHEC is a simplification but it catches the large bulk of regulatory issues related to MR. In art. 30, EC the key references are to health and safety and possibly elements of environmental policy. As far as the ‘rule of reason’ case law of art. 28, EC is concerned, it underpins environmental and consumer protection. In addition, some other justifications can be found here, all of marginal importance. For legal analysis, see, for example, Barnard Citation(2004), chapters 6 and 18, as well as Weiler Citation(2005). 3 For details, see for example, Atkins Citation(1997), also Pelkmans Citation(1987) for the many drawbacks of the Old Approach. A good example is tractor safety regulation. There are 23 tractor directives. 4 See, for instance, directive 94/9/EC on equipment and protective systems intended for use in explosive atmospheres (ATEX dir.) <http://ec.europa.eu/comm/enterprises/atex/guide/index.htm> or the entire debate on detailed testing requirements for some 30,000 long known chemicals in the framework of REACH; see Pelkmans Citation(2005b). 5 A typical case being the toys directive 88/378/EEC. An extremely broad application is the machines directive 98/37/EC, covering more than 40,000 types of ‘machines’. 6 Indeed, often for the European Economic Area (EEA) – the EU plus Norway, Liechtenstein and Iceland – and even wider. 7 This is referred to as the ‘presumption’ of compliance. 8 Or from other EEA countries or Turkey, the latter because of the ‘deep’ customs union with the EU 25. 9 Of course, the New Approach is also subject to further improvements. See COM (2003) 240 of 7 May 2003 and the suggestions in the twentieth anniversary conference of the New Approach, 30 November 2005, at <http://europa.eu.int/comm/enterprise/newapproach/new_approach_conference_en.htm> 10 The Commission's interpretative communication on the practical application of MR, 2003/C 265 of 4 November 2003. It specifies, furthermore, undue translation requirements, no duplication of tests, recognition of testing and certification based on EN 45,000 standards of quality and independence, and no additional tests not required for domestic companies. 11 A famous example is the Beer Purity Law in Germany where the ECJ held that the pursuit of consumer protection should be conducted with measures such as labelling rather than an import ban. Case 274/87 Commission vs. Germany, [1989] ECR 229. 12 It is possible, though rare, that national regulations are drafted for SHEC objectives where approximation failed, say, because of a split in the Council or because of extreme uncertainty in science, hence risk assessment. In such instances, MR would also fail because of a lack of equivalence. One such case is that of so-called ‘fortified foods’, where sharp differences between the member states and at times contrasting views by scholars pre-empted Commission proposals. See Atkins Citation(1997), chapter 17, for details. After a struggle lasting decades, the Commission proposed a partial remedy in COM (2003) 424 of 16 July 2003 on nutrition and health claims made for foods. In May 2006 the draft was in its second reading and likely to be adopted. 13 The EU standards bodies are CEN, CENELEC and ETSI. See < http://www.cenorm.be>, <http://www.cenelec.org> and <http://www.etsi.org>. 14 World standards are written by the International Organization Standarlization (ISO) and the International Electrotechnical Committee (IEC) and for telecoms by a special committee of the International Telecommunication Union (ITU). All three European bodies have formal agreements with the world bodies about procedures which facilitate the fullest possible use of world standards (where they exist; for goods, rather than processes, testing or for information, world standards are often absent) as European standards. 15 Member states and the Commission can give observations (also called ‘comments’), besides so-called ‘detailed opinions’, which reflect serious concerns about prospective barriers. Both are included in Figure 2. If a member state does not adjust drafts after ‘detailed opinions’, it risks an infringement procedure, or the Commission might regard the matter as so problematic that it proposes a directive. 16 The following is adapted from Pelkmans Citation(2005a) and Pelkmans (Citation2006: section 4.4.3.). 17 See COM (1999) 299 of 16 June 1999 on MR in the internal market, COM (2002) 419 of 23 July 2002 (second biannual report on MR), The Internal Market Scoreboard no. 10 of May 2002. 18 Since July 2006, the new address of the TRIS (technical regulation information system) website is: <http://ec.europe.eu/enterprise/tris/index_en.htm>; it collects information on the removal or prevention of regulatory (mainly technical) barriers to free movement. 19 SOLVIT is an on-line problem-solving network of national officials, co-ordinated by the Commission. It tackles complaints about the misapplication of internal market law by public (and also local) authorities, but without legal proceedings, in a period of a maximum of ten weeks. SOLVIT claims (September 2006) a success rate of 75 per cent of cases solved, a clear incentive to use it. Some 16 per cent of the cases are about market access of goods (i.e. often MR). See <http://ec.europa.eu/solvit/site/about/index_en.htm>. 20 For a recent overview, see the Commission's 2003 interpretative communication on … the practical application of MR, as in note 15.
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