Isoimmunization in the human subject to the blood group factors A, B and Rh

The process by which specific antibodies are formed in an individual in response to stimulation by an antigen is called immunization. An antigen which is contained in some individuals of a species may, under suitable conditions, stimulate the production of specific antibodies when injected into other individuals of the same species who do not already possess the antigen. This process is called iso-immuhization and the antibodies produced are iso-antibodies. The first experiments on this subject were made on animals (6) by Ehrlich and Morgenroth who discovered that when one goat was iniected with the blood of another goat, immune iso-haemolysins(8)became apparent in its serum. in 1933 Irwin and Hill madeuse of the phenomenon of iso-immunization for the purpose of studying the cellular individuality of erythrocytes in doves. Back cross-hybrids were joined by parabiosis and it was found that each member of a pair of parabiotic twins developed antibodies against the erythrocytes of the other, due to mutual (3)iso-immunization. Dienst first suggested that there might be Iso-immunization within the human species. He showed that following pregnancy in some cases there was an increase in the Anti-A or anti-B iso-agglutinin titre of the mother's serum when the infant's erythrocytes contained a corresponding, A or B agglutinogen.<p

Two point correlations of a trapped interacting Bose gas at finite temperature

We develop a computationally tractable method for calculating correlation functions of the finite temperature trapped Bose gas that includes the effects of s-wave interactions. Our approach uses a classical field method to model the low energy modes and treats the high energy modes using a Hartree-Fock description. We present results of first and second order correlation functions, in position and momentum space, for an experimentally realistic system in the temperature range of $0.6T_c$ to $1.0T_c$. We also characterize the spatial coherence length of the system. Our theory should be applicable in the critical region where experiments are now able to measure first and second order correlations.Comment: 9 pages, 4 figure

The working practices and clinical experiences of paediatric speech and language therapists: a national UK survey

Background: The majority of speech and language therapists (SLTs) work with children who have speech, language and communication needs. There is limited information about their working practices and clinical experience and their views of how changes to healthcare may impact upon their practice. Aims: To investigate the working practices and professional experiences of paediatric SLTs working in the UK through an online survey. Methods & Procedures: The survey was conducted online using Survey Monkey. Therapists were alerted to the survey through the Bulletin of the Royal College of Speech and Language Therapists and by e-mails to national special interest groups. Outcomes & Results: A total of 516 clinicians completed the survey. A large majority worked in the National Health Service (NHS). A varied pattern of working was revealed. Most worked in several settings and saw a range of clients. A typical clinician spends less than one-quarter of their time giving direct therapy and more than one-quarter training parents and other professionals. Nearly half of respondents felt that their time could be better used. Too little time for direct therapy and the time required for administration emerged as their principal concerns. Most clinicians have specialist knowledge of particular client groups and spend more time with them than do non-specialists. Nevertheless, clients are more likely to be treated by a therapist who does not claim to have specialist knowledge of their condition than by one who does. The only clients for whom this is not the case are those with dysphagia. Eighty per cent of respondents felt that proposed changes to the NHS would not benefit the children they treat and there was widespread concern about cuts and the effects of general practitioner commissioning. Despite this, a large majority expected to remain speech and language therapists 5 years from now. Conclusions & Implications : This survey provides an overview of the working practices of paediatric speech and language therapists. Its findings have significant implications for training and workforce development in the profession

User needs, benefits and integration of robotic systems in a space station laboratory

The methodology, results and conclusions of the User Needs, Benefits, and Integration Study (UNBIS) of Robotic Systems in the Space Station Microgravity and Materials Processing Facility are summarized. Study goals include the determination of user requirements for robotics within the Space Station, United States Laboratory. Three experiments were selected to determine user needs and to allow detailed investigation of microgravity requirements. A NASTRAN analysis of Space Station response to robotic disturbances, and acceleration measurement of a standard industrial robot (Intelledex Model 660) resulted in selection of two ranges of low gravity manipulation: Level 1 (10-3 to 10-5 G at greater than 1 Hz.) and Level 2 (less than = 10-6 G at 0.1 Hz). This included an evaluation of microstepping methods for controlling stepper motors and concluded that an industrial robot actuator can perform milli-G motion without modification. Relative merits of end-effectors and manipulators were studied in order to determine their ability to perform a range of tasks related to the three low gravity experiments. An Effectivity Rating was established for evaluating these robotic system capabilities. Preliminary interface requirements were determined such that definition of requirements for an orbital flight demonstration experiment may be established

Slow 4He^{4}He Quenches Produce Fuzzy, Transient Vortices

We examine the Zurek scenario for the production of vortices in quenches of liquid $^{4}He$ in the light of recent experiments. Extending our previous results to later times, we argue that short wavelength thermal fluctuations make vortices poorly defined until after the transition has occurred. Further, if and when vortices appear, it is plausible that that they will decay faster than anticipated from turbulence experiments, irrespective of quench rates.Comment: 4 pages, Revtex file, no figures Apart from a more appropriate title, this paper differs from its predecessor by including temperature, as well as pressure, quenche

Speech production in children with Down's syndrome: The effects of reading, naming and imitation

People with DS are known to have difficulties with expressive language, and often have difficulties with intelligibility. They often have stronger visual than verbal short-term memory skills and, therefore, reading has often been suggested as an intervention for speech and language in this population. However, there is as yet no firm evidence that reading can improve speech outcomes. This study aimed to compare reading, picture naming and repetition for the same 10 words, to identify if the speech of eight children with DS (aged 11-14 years) was more accurate, consistent and intelligible when reading. Results show that children were slightly, yet significantly, more accurate and intelligible when they read words compared with when they produced those words in naming or imitation conditions although the reduction in inconsistency was non-significant. The results of this small-scale study provide tentative support for previous claims about the benefits of reading for children with DS. The mechanisms behind a facilitatory effect of reading are considered, and directions are identified for future research

On the dispersionless Kadomtsev-Petviashvili equation in n+1 dimensions: exact solutions, the Cauchy problem for small initial data and wave breaking

We study the (n+1)-dimensional generalization of the dispersionless Kadomtsev-Petviashvili (dKP) equation, a universal equation describing the propagation of weakly nonlinear, quasi one dimensional waves in n+1 dimensions, and arising in several physical contexts, like acoustics, plasma physics and hydrodynamics. For n=2, this equation is integrable, and it has been recently shown to be a prototype model equation in the description of the two dimensional wave breaking of localized initial data. We construct an exact solution of the n+1 dimensional model containing an arbitrary function of one variable, corresponding to its parabolic invariance, describing waves, constant on their paraboloidal wave front, breaking simultaneously in all points of it. Then we use such solution to build a uniform approximation of the solution of the Cauchy problem, for small and localized initial data, showing that such a small and localized initial data evolving according to the (n+1)-dimensional dKP equation break, in the long time regime, if and only if n=1,2,3; i.e., in physical space. Such a wave breaking takes place, generically, in a point of the paraboloidal wave front, and the analytic aspects of it are given explicitly in terms of the small initial data.Comment: 20 pages, 10 figures, few formulas adde

Coherent control of stimulated Raman scattering using chirped laser pulses

A novel method for the control of stimulated Raman scattering and hot electron production in short-pulse laser-plasma interactions is proposed. It relies on the use of a linear frequency chirp in nonbandwidth limited pulses. Theoretical calculations show that a 12% bandwidth will eliminate Raman forward scattering for a plasma density that is 1% of the critical density. The predicted changes to the growth rate are confirmed in two-dimensional particle-in-cell simulations. Relevance to areas of current research is also discussed. © 2001 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70620/2/PHPAEN-8-8-3531-1.pd

New Experiments for Spontaneous Vortex Formation in Josephson Tunnel Junctions

It has been argued by Zurek and Kibble that the likelihood of producing defects in a continuous phase transition depends in a characteristic way on the quench rate. In this paper we discuss an improved experiment for measuring the Zurek-Kibble scaling exponent $\sigma$ for the production of fluxons in annular symmetric Josephson Tunnel Junctions. We find $\sigma \simeq 0.5$. Further, we report accurate measurements of the junction gap voltage temperature dependence which allow for precise monitoring of the fast temperature variations during the quench.Comment: 12 pages, 5 figures, submitted to Phys. Rev.