2,329 research outputs found
Present day views of asthma: with special reference to etiology and treatment and including an analysis of 117 cases
1. Asthma is a comparatively common disease in
British Guiana.
2. Clinically, asthma can be divided into two
types, one termed primary for convenience and in
which there is usually a family history of asthma,
hay fever or allergic manifestations such as eczema,
urticaria, cyclic vomiting or migraine. This type
usually begins in childhood. The other, termed
"secondary ", usually follows some respiratory
affection e.g. measles, whooping cough, bronchitis
or pneumonia and usually starts in later life.
Oriel and Knott have found in these two types
(38) (39)
biochemical differences which tend to support this
clinical differentiation.
3. In the diagnosis and treatment of the condition, Ascaris lumbricoides infection must be kept
in mind and stool examination for eggs of this
helminth should be practised as a routine in all
cases of asthma in the tropics if only to exclude
this condition.
4. A number of factors probably operate in the
production of this malady. The one constant factor
appears to be an inherited diathesis or predisposition,
though in some cases this predisposition may
be acquired. Other factors such as allergy, toxaemia,
reflex irritation, psychical disturbances,
biochemical changes and endocrine disturbances all
may play their role in the production of this distressing
disease. Only time and experience will determine
the relative merits of each.
5. Early treatment is of the greatest importance.
6. No one treatment is applicable to every case
of asthma. Each case requires thorough investigation
and individual treatment.
7. The most successful form of therapy is by
elimination, when applicable.
8. If the specific cause cannot be eliminated
or avoided, specific desensitisation should be
attempted.
9. If the specific cause cannot be determined,
recourse must be had to non-specific desensitisation
with peptone, milk, tuberculin or vaccines. It
is always worth while trying different forms of
treatment since in many cases where one form of
therapy fails another may succeed.
10. Psycho-analysis and endocrine therapy may
be indicated in individual cases.
11. In adults, arsenic in the form of neo-arsenobillon
intravenously the author has found of
benefit and often succeeds where other methods of
treatment fail
A Comparison of the High-Frequency Magnetic Fluctuations in Insulating and Superconducting La2-xSrxCuO4
Inelastic neutron scattering performed at a spallation source is used to make
absolute measurements of the dynamic susceptibility of insulating La2CuO4 and
superconducting La2-xSrxCuO4 over the energy range 15<EN<350 meV. The effect of
Sr doping on the magnetic excitations is to cause a large broadening in
wavevector and a substantial change in the spectrum of the local spin
fluctuations. Comparison of the two compositions reveals a new energy scale of
22 meV in La1.86Sr0.14CuO4.Comment: RevTex, 7 Pages, 4 postscript figure
A Survey of Activity-Based Costing (ABC) Practices within the Department of the Army
Activity-Based Costing (ABC) does not appear to have been as readily accepted within the Department of the Army as within private industry (Kehoe et al., 1995). Barely able to accomplish their missions at current resource levels, military resource managers know historically that identified efficiencies and savings often are translated into self inflicted budget and manpower cuts. Yet, it is almost universally accepted that the benefits of using Activity-Based Costing are real and obtainable, but not yet worth the effort required with the perceived risk being taken. Current conventional wisdom is for Army Resource Managers to wait and see what benefits and fates come to those who pioneer ABC. The US Army Cost and Economic Analysis Center (CEAC) had been charged with the role of establishing policy for ABC within the Army. Wanting to base policy on successful applications, their first task is to define Army ABC, and then to find such initiatives from which to draw from. The purpose of this thesis is to find Activity-Based Costing practices within the US Army, and then to use them to discover the major dimensions of ABC in the Army environment. This research found that the home of Activity-Based Costing is in the Army Major Commands and their subcommands. Within these commands there is much interest in ABC, but efforts are stymied by lack of policy and widespread knowledge of ABC principles. Training is perceived not as individual, but as an organizational need. Base Operations was identified as the area most suitable for ABC, while combat units the least. Overall ABC is generally considered to be a positive tool which can be employed to help leadership better manage their operations and resources
Observation of Magnetic Order in a Superconductor
Polarized beam neutron scattering measurements on a highly perfect crystal of
show a distinct magnetic transition with an onset at
about 235K, the temperature expected for the pseudogap transition. The moment
is found to be about 0.1 for each sublattice and have a correlation
length of at least 75 \AA. We found the critical exponent for the magnetic
neutron intensity to be 2 =0.37 0.12. This is the proper range for
the class of transition that has no specific heat divergence possibly
explaining why none is found at the pseudogap transition.Comment: 3 figure
Observation of Magnetic Moments in the Superconducting State of YBaCuO
Neutron Scattering measurements for YBaCuO have identified
small magnetic moments that increase in strength as the temperature is reduced
below and further increase below . An analysis of the data shows
the moments are antiferromagnetic between the Cu-O planes with a correlation
length of longer than 195 \AA in the - plane and about 35 \AA along the
c-axis. The origin of the moments is unknown, and their properties are
discusssed both in terms of Cu spin magnetism and orbital bond currents.Comment: 9 pages, and 4 figure
Magnetic Order in YBaCuO Superconductors
Polarized and unpolarized neutron diffraction has been used to search for
magnetic order in YBaCuO superconductors. Most of the
measurements were made on a high quality crystal of YBaCuO. It
is shown that this crystal has highly ordered ortho-II chain order, and a sharp
superconducting transition. Inelastic scattering measurements display a very
clean spin-gap and pseudogap with any intensity at 10 meV being 50 times
smaller than the resonance intensity. The crystal shows a complicated magnetic
order that appears to have three components. A magnetic phase is found at high
temperatures that seems to stem from an impurity with a moment that is in the
- plane, but disordered on the crystal lattice. A second ordering occurs
near the pseudogap temperature that has a shorter correlation length than the
high temperature phase and a moment direction that is at least partly along the
c-axis of the crystal. Its moment direction, temperature dependence, and Bragg
intensities suggest that it may stem from orbital ordering of the -density
wave (DDW) type. An additional intensity increase occurs below the
superconducting transition. The magnetic intensity in these phases does not
change noticeably in a 7 Tesla magnetic field aligned approximately along the
c-axis. Searches for magnetic order in YBaCuO show no signal
while a small magnetic intensity is found in YBaCuO that is
consistent with c-axis directed magnetic order. The results are contrasted with
other recent neutron measurements.Comment: 11 pages with 10 figure
X-Ray-Diffraction Study of Charge-Density-Waves and Oxygen-Ordering in YBa2Cu3O6+x Superconductor
We report a temperature-dependent increase below 300 K of diffuse
superlattice peaks corresponding to q_0 =(~2/5,0,0) in an under-doped
YBa_2Cu_3O_6+x superconductor (x~0.63). These peaks reveal strong c-axis
correlations involving the CuO_2 bilayers, show a non-uniform increase below
\~220 K with a plateau for ~100-160 K, and appear to saturate in the
superconducting phase. We interpret this unconventional T-dependence of the
``oxygen-ordering'' peaks as a manifestation of a charge density wave in the
CuO_2 planes coupled to the oxygen-vacancy ordering.Comment: 4 pages, 4 figure
Detection of the Unusual Magnetic Orders in the Pseudogap Region of a High-Temperature Superconducting YBa2Cu3O6.6 Crystal by Muon-Spin Relaxation
We present muon spin relaxation (muSR) measurements on a large YBa2Cu3O6.6
single crystal in which two kinds of unusual magnetic order have been detected
in the pseudogap region by neutron scattering. A comparison is made to
measurements on smaller, higher quality YBa2Cu3Oy single crystals. One type of
magnetic order is observed in all samples, but does not evolve significantly
with hole doping. A second type of unusual magnetic order is observed only in
the YBa2Cu3O6.6 single crystal. This magnetism has an ordered magnetic moment
that is quantitatively consistent with the neutron experiments, but is confined
to just a small volume of the sample (~ 3%). Our findings do not support
theories that ascribe the pseudogap to a state characterized by loop-current
order, but instead indicate that dilute impurity phases are the source of the
unusual magnetic orders in YBa2Cu3Oy.Comment: 4 pages, 4 figure
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