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Notes: This paper presents a design for a Fabry–Perot optical frequency reference resonator which utilizes the high dimensional stability of cryogenically cooled sapphire. We show that cryogenic sapphire cavities can achieve substantial improvements in frequency stability compared with room-temperature cavities. The design of a laser stabilization system based on such a resonator is discussed. Estimates of fundamental and practical limitations on the frequency stability of such a system suggest that a fractional frequency stability of 10−16 over integration times from 10 to 104 s is possible. The fundamental limits to stability from quantum shot noise, radiation pressure fluctuations, and thermal noise are overwhelmed by practical limits which arise due to mechanical, thermal, and optical effects. © 1995 American Institute of Physics.

Notes: Objective To study the pathological features of fetuses dying because of parvovirus B19 infection, with particular reference to the presence of hydrops; to assess the usefulness of immunochemistry as a screening method for the detection of parvovirus infection at post-mortem examination.Design Review of clinical, sonographic, serological and pathological data; immunohistochemical staining of post-mortem tissue.Sample Cases of intrauterine fetal death occurring during the 18-month period January 1993 to June 1994 inclusive, referred for post-mortem examination to the Pathology Department, Royal Victoria Infirmary, Newcastle upon Tyne.Results Eleven cases of fetal death due to parvovirus infection were identified. Seven fetuses were less than 18-week size. Three fetuses showed conspicuous hydropic change. One of the 11 cases was detected for the first time by retrospective immunochemical screening. Of cases originating from the Newcastle district, parvovirus infection was responsible for about 10YO of all non-malformed fetal deaths occurring between 10 and 24 weeks of gestation referred for pathological examination.Conclusions During the period of study, parvovirus infection was a relatively common cause of mid-trimester fetal death. Many fetuses dying because of this infection are not noticeably hydropic, and the possibility of parvovirus infection should be considered in any case of intrauterine fetal death. Immunochemistry can be used to confirm the histopathological diagnosis, and may be of particular help where there is advanced autolysis; immunohistochemical screening may detect occasional cases not initially identified by examination of routinely stained tissue sections.

Notes: The effect of adding Lactobacillus buchneri 40788, a heterofermentative lactobacilli, to whole-plant maize and its effect on fermentation and aerobic stability of the resulting silage were evaluated. Whole-plant maize (380 g DM kg–1 fresh weight) was ensiled in laboratory silos after the following treatments: untreated, L. buchneri 40788 at 1 × 105, 2·5 × 105, 5 × 105, and 1 × 106 colony forming units g–1 of fresh forage or, a commercial inoculant containing homolactic acid bacteria, a single species of propionibacteria and enzymes. Addition of L. buchneri 40788 resulted in a decrease in lactic acid concentration but increased the concentration of acetic acid in silage and markedly decreased the numbers of yeasts present in the silage. All levels of L. buchneri 40788, increased the aerobic stability of silages but the effect was greatest for the two highest levels of inoculation. Treatment with the commercial inoculant had no effect on the fermentation or aerobic stability of silage. On-farm treatment of maize silage with L. buchneri 40788, stored in a bag silo, resulted in changes in fermentation that were similar to those observed in laboratory silos. Treatment decreased the numbers of yeast in silage and increased aerobic stability (+25 h) of the silage when exposed to air. Treatment had no effect on the dry-matter intake of silage fed to sheep. These results showed that treating silage with L. buchneri 40788 can increase the aerobic stability of maize silage in laboratory and farm silos.

Notes: The LBNL third generation electron cyclotron resonance (ECR) ion source has progressed from a concept to the fabrication of a full scale prototype superconducting magnet structure. This new ECR ion source will combine the recent ECR ion source techniques that significantly enhance the production of high charge state ions. The design includes a plasma chamber made from aluminum to provide additional cold electrons, three separate microwave feeds to allow multiple-frequency plasma heating (at 10, 14, and 18 GHz or at 6, 10, and 14 GHz) and very high magnetic mirror fields. The design calls for mirror fields of 4 T at injection and 3 T at extraction and for a radial field strength at the wall of 2.4 T. The prototype superconducting magnet structure which consists of three solenoid coils and six race track coils with iron poles forming the sextupole has been tested in a vertical Dewar. After training, the sextupole magnet reached 105% of its design current with the solenoids off. With the solenoids operating at approximately 70% of their full design field, the sextupole coils operated at 95% of the design value which corresponds to a sextupole field strength at the plasma wall of more than 2.1 T. © 1998 American Institute of Physics.

Notes: Four articles have been published in this Journal about the historic cattle trial, Pickett v Tyson Fresh Meats, Inc., in which Plaintiff cattlemen alleged that Tyson/IBP--the buyer--used captive (contracted) supplies of cattle to manipulate the cash market in violation of the 1921 Packers & Stockyards Act (PSA). The first article gave a Trial's eye view by David Domina who served as co-lead counsel representing Plaintiff cattlemen. Domina's article led to a published comment by Thomas Green who was the lead attorney representing Tyson during the Trial phase of lengthy legal proceedings. Green alleged that Domina's article was "littered with rank speculation and baseless opinion." Domina countered that "proof is not litter, and evidence is not rank speculation" and that Green's commentary was "abusive." The adversarial exchange between Domina and Green was followed by another advocacy article in which William Rosales maintained that Pickett "represents an opportunity for the judiciary to reform the meatpacking industry (and) awaken the (PSA's) intended power to dethrone the economic kings of the meatpacking industry."After a five week Trial in Federal Court, the Jury found Tyson/IBP guilty on all counts and assessed actual damages of $1.28 billion over 2/1994 -10/2002. Justice for Plaintiff cattlemen was short, as the Trial Judge set aside the Jury's verdict--a rare but not unprecedented legal action--and entered summary judgment for Tyson. The Eleventh Appellate Court subsequently sided with the Trial Judge. On March 24, 2006, the United States Supreme Court denied without comment Plaintiff's Petition to rehear the case, thus ending legal activities in Pickett v Tyson and effectively killing similar legal action pending against two other major beef packers, Excel (Cargill) and Swift (ConAgra).This article emphasizes three significant and troubling legal and economic issues from the historic litigation: (1) the Courts' narrow and extreme interpretation of the antitrust rule-of-reason; (2) the Courts' endorsement of a "meeting the competition" defense, and (3) whether the Courts inserted themselves above the Jury as fact-finders in the case, contrary to the 7th Amendment to the U.S. Constitution that establishes the Jury as the only fact-finder in civil litigation.In essence Pickett was filed under the Packers and Stockyards Act, tried under Sherman and Clayton antitrust law, and overturned, in part, under the Robinson-Patman Act.

Notes: An array of microlenses, with focal lengths that can be electrically varied, can control the coupling of light into a single mode fiber using an applied voltage. We have examined this technology with a view to the design of a confocal microlens/image-fiber endoscope. Maximum coupling to the fiber was found to occur over a voltage range of ∼1 V and over an axial range of 1 cm. Contrast ratios between minimum and maximum coupling of up to 30 dB were demonstrated. © 2001 American Institute of Physics.

Notes: Single leaves of 3-month-old Cedrella odorata seedlings were exposed to a step reduction in the ambient dew point. The resultant time series of dynamic variations in leaf surface water vapour concentration, leaf surface water vapour concentration gradient, transpiration rate and stomatal conductance to water vapour, are analysed using the data-based mechanistic (DBM) modelling methodology of Young (e.g. Young & Lees 1992; Minchin et al. 1996 ). It is shown that the identified second-order, dynamic model between transpiration rate (as the input) and stomatal conductance (as the output) provides an appropriate, physiologically meaningful, description of the system. In particular, the dynamic relationship between these two variables is remarkably linear and can be resolved in terms of two parallel, first-order, subsystems; a model which complements the results of Cowan (1977) for cotton. The model is also compared with the recently published simulation model of Haefner, Buckley & Mott (1997).

Notes: Aims  To investigate heroin and cocaine use in a sample of British prisoners, and to explore the characteristics of inmates who use these drugs for the first time while in prison.Design, participants  A cross-sectional survey of all prisons in England and Wales conducted as part of a major national study of psychiatric morbidity. A total of 3142 prisoners (88.2% of those selected) completed a structured interviewer-administered questionnaire.Measurements  Interview measures of personal demographics, social history, psychiatric morbidity and drug use. Personality disorders were diagnosed via the Structured Clinical Interview for DSM-IV (SCID-II) and neurotic symptoms were assessed using the revised Clinical Interview Schedule (CIS-R).Findings  More than 60% of the heroin users and cannabis users reported that they had used these drugs in prison compared with less than a quarter of the life-time cocaine users. More than a quarter of the heroin users reported that they had initiated use of this drug in prison. The extent of an individual's experience of prison was related more consistently to heroin and/or cocaine use in and out of prison than other personal background, social history or psychiatric variables assessed.Conclusions  The findings indicate that prisons are a high-risk environment for heroin and other drug initiation and use. Although related to drug use, psychiatric variables were not generally associated with initiation in prison, which was dominated by prison exposure. There is a need to explore ways of reducing heroin initiation in prison as part of a broader risk-prevention strategy.