2,621 research outputs found
Bacteriological and epidemiological studies of streptococcal infections: with particular reference to epidemiological analyses by serological typing of haemolytic streptococci
(1) PREPARATION OF TYPE -SPECIFIC SERA:
(a) Vaccine was prepared from Griffith's thirty
types of haemolytic streptococci.
(b) Rabbits were injected and test-bleedings made
at various times to estimate the titre of the serum.
(c) The method of preparing type- specific agglutinating sera was described, and particular mention of
cross -reactions was made.(2) THE TYPING OF HAEMOLYTIC STREPTOCOCCI:
(a) A series of investigations were carried out t
determine the most suitable media for growing homogeneous suspensions of haemolytic streptococci.
The method of incubation best suited was
described.
(b) A description of the slide -agglutination method
of typing used throughout this work was given.CLINICO- BACTERIOLOGICAL INVESTIGATIONS OF
SCARLET FEVER CASES.
(3) The procedure adopted in swabbing patients
was intimated.(4) There followed a description of the method
adopted for storing haemolytic streptococci "in vacuo".(5) Statistical records for the period September 1937 to January 1939 were drawn up and included
the total number of admissions of scarlet fever cases
to the City Fever Hospital, the total number swabbed,
the total number of complications, and the total
number of complications swabbed.(6) Monthly graphs and tables indicating the
result of typing the above cases was given.(7) The monthly percentage increase and decrease
of the various types of haemolytic streptococci were
recorded.(8) An investigation was carried out to show
whether any difference in the types of haemolytic
streptococci found in the throats and noses of scarlet
fever cases existed.(9) The next investigation was carried out to
determine whether there occurred more than one type of
haemolytic streptococcus in the throat swabs of
patients on admission to hospital.(10) This investigation was an attempt to ascertain whether any cases, which had been in the wards
for some time, had more than one type of haemolytic
streptococci in their throats.(11) The results of the last investigation were
compared with those found during the first day complications became manifest.(12) Daily swabs were taken in a single ward
over a period of 23 days and all the patients typed.
All cross- infections were noted.(13) The same investigation was carried out over
a period of 46 days.(14) 384 cases showing complications were investigated. The haemolytic streptococci present on
admission and those responsible for the complications
were noted. Correlations between types and lesions,
etc., were recorded.(1 5) An investigation was undertaken showing the
decrease of haemolytic streptococci in the throats of
patients during their stay in hospital.(16) During the month of May, 1938, twenty cases
of scarlet fever were typed and the same done to fifteen cases showing complications. The results were
investigated.(17) A statistical record of scarlet fever cases
occurring in the City of Edinburgh from the 1/9/37 to
31/12/38 was drawn up.(18) The number of patients per month from the
various schools and institutions in Edinburgh was calculated and recorded in tables.A graph comparing the number of school children
with all other cases is given.(19) The types of haemolytic streptococci found
in school cases and other patients were noted and
certain correlations observed.(20) An attempt was made to show that there
existed a relationship of types of haemolytic streptococci found in the patients from individual schools.(21) 54 cases of puerperal fever were investigated bacteriologically.(22) Similarly 40 cases of erysipelas were
investigated.(23) This was also done with 10 cases of otitis
media or mastoiditis, and(24) with 60 cases of tonsillitis.(25) A miscellaneous group of diseases sent into
the City Fever Hospital as scarlet fever cases was
examined for haemolytic streptococci (42 patients).(26) Eight positive haemolytic streptococci
;swabs from the Third Year Medical Students were examined. This was carried out during a time when "coughs,
and colds" were common.(27) 32 cases of respiratory diseases occurring
in a rural area were investigated for the presence of
haemolytic streptococci. These were typed and compared with the urban strains.(28) The next investigation was carried out to
ascertain the presence of haemolytic streptococci in
normal throats and to find what correlation there
existed between the types found and the various streptococcal infections. The normal throats were those of:
(a) 40 nurses from the City Fever Hospital.
(b) The positive swabs from a number of nurses
from the Western General Hospital,
(c) Six resident doctors in the City Fever Hospital.
(d) Ten strains from the Third Year Medical students were typed. The period was one when
only a few "coughs and colds" were about.
(e) 16 families, from whom cases of scarlet fever
had been sent to hospital, were visited and
all members swabbed, with a view to determining the presence of haemolytic streptococci and observing any correlations.
260
(f) This investigation was carried out upon my own'
person to estimate the number of haemolytic
streptococci present in throat and nose
before and after contact with scarlet fever
patients.(29) The presence of haemolytic streptococci on
toys and food in the scarlet fever wards was investigated.(30) A similar investigation was carried out on
the handkerchiefs of patients.AIR -CONTAMINATION WITH HAEMOLYTIC STREPTOCOCCI
IN THE CITY FEVER HOSPITAL WARDS.(31) (a) A research was made to determine the
incidence of haemolytic streptococci in the air of
fever wards.
(b) A similar investigation was done in a
puerperal ward; and in
(c) an erysipelas ward; and in
(d) a diphtheria; and in
(e) a measles ward.
(f) The first investigation (a) was
repeated in a ward with a high complication rate, and
repeated in another with a low complication rate. The
results were correlated.(32) Air contamination with haemolytic streptococci in the Ear, Nose and Throat Department of the
Edinburgh Royal Infirmary was investigated.(33) The next investigation was to determine
the presence of haemolytic streptococci and their
types in picture houses, buses, trams, shops and
open places.(34) An attempt was made to correlate the
types found in scarlet fever with those of all other
streptococcal infections.(35) A research into the problem of air-borne
infection was carried out. The object of this investigation was to determine what effects variations of
ventilation, and wet and dry sweeping have on the
number of organisms in the air.B. prodigiosus was the organism used in this
investigation and was sprayed by means of an atomiser.(36) Cross-contamination in the cubicles of the
City Fever Hospital was investigated.(37) The final investigation was an attempt to
type those strains of haemolytic streptococci which
were either too granular or failed to type by ordinaryj
methods
The Concept of Fact in German Physics around 1900: A Comparison between Mach and Einstein
The concept of fact has a history. Over the past centuries, physicists have
appropriated it in various ways. In this article, we compare Ernst Mach and
Albert Einstein's interpretations of the concept. Mach, like most
nineteenth-century physicists, contrasted fact and theory. He understood facts
as real and complex combinations of natural events. Theories, in turn, only
served to order and communicate facts efficiently. Einstein's concept of fact
was incompatible with Mach's, since Einstein believed facts could be
theoretical too, just as he ascribed mathematical theorizing a leading role in
representing reality. For example, he used the concept of fact to refer to a
generally valid result of experience. The differences we disclose between Mach
and Einstein were symbolic for broader tensions in the German physics
discipline. Furthermore, they underline the historically fluid character of the
category of the fact, both within physics and beyond.Comment: Physics in Perspective, 202
Estimating classification error under edit restrictions in combined survey-register data using Multiple Imputation Latent Class modelling (MILC)
Both registers and surveys can contain classication errors. These errors can be estimated by making use of information that is obtained when making use of a combined dataset. We propose a new method based on latent class modelling that estimates the number of classification errors in the multiple sources, and simultaneously takes impossible combinations with other variables into account. Furthermore, we use the latent class model to multiply impute a new variable, which enhances the quality of statistics based on the combined dataset. The performance of this method is investigated by a simulation study, which shows that whether the method can be applied depends on the entropy of the LC model and the type of analysis a researcher is planning to do. Furthermore, the method is applied to a combined dataset from Statistics Netherlands
Nematode control in suckler beef cattle over their first two grazing seasons using a targeted selective treatment approach
peer-reviewedBackground
With concerns over the development of anthelmintic resistance in cattle nematode populations, we must re-examine our approach to nematode control in cattle. Targeted selective treatments (TST), whereby individual animals are treated instead of entire groups, are being investigated as an alternative. The study objective was to determine if anthelmintic usage could be reduced using a TST-based approach to nematode control in spring-born suckler beef cattle over their first and second grazing seasons (SGS) without affecting performance. In the first grazing season (FGS), 99 calves with an initial mean (s.d.) calf age and live weight on day 0 (June 28th 2012) of 107 (23.1) days and 160 (32.5) kg, respectively, were used. The study commenced on day 0 when calves were randomised and allocated to one of two treatments; 1), standard treatment (control) and 2), TST. Control calves were treated subcutaneously with ivermectin on days 0, 41 and 82 in the FGS. All calves were treated with ivermectin on day 124 and housed on day 133. In the SGS, only heifer calves from the FGS were used and control heifers were treated with ivermectin on day 393. Animals were weighed, blood and faecal sampled every three weeks. The TST animals were treated with ivermectin if thresholds based on a combination of plasma pepsinogen concentrations, faecal egg count and/or the presence of Dictyocaulus viviparus larvae in faeces (FGS only) were reached.
Results
No TST calves reached the treatment threshold criteria in the FGS. The FGS average daily live weight gain (ADG ± s.e.m.) for control and TST group calves was 0.89 ± 0.02 kg and 0.94 ± 0.02 kg day−1, respectively (P = 0.17). In the SGS, all heifers were treated with ivermectin on day 431 due to clinical signs of respiratory disease. The ADG for control and TST heifers from turnout on day 321 to day 431 was 0.90 ± 0.04 and 0.80 ± 0.04 kg day−1, respectively (P = 0.03).
Conclusions
Spring-born FGS suckler beef calves require minimal anthelmintic treatment to maintain performance. In contrast, clinical parasitic disease may develop in the SGS unless appropriate anthelmintic treatment is provided
On Finding Maximum Cardinality Subset of Vectors with a Constraint on Normalized Squared Length of Vectors Sum
In this paper, we consider the problem of finding a maximum cardinality
subset of vectors, given a constraint on the normalized squared length of
vectors sum. This problem is closely related to Problem 1 from (Eremeev,
Kel'manov, Pyatkin, 2016). The main difference consists in swapping the
constraint with the optimization criterion.
We prove that the problem is NP-hard even in terms of finding a feasible
solution. An exact algorithm for solving this problem is proposed. The
algorithm has a pseudo-polynomial time complexity in the special case of the
problem, where the dimension of the space is bounded from above by a constant
and the input data are integer. A computational experiment is carried out,
where the proposed algorithm is compared to COINBONMIN solver, applied to a
mixed integer quadratic programming formulation of the problem. The results of
the experiment indicate superiority of the proposed algorithm when the
dimension of Euclidean space is low, while the COINBONMIN has an advantage for
larger dimensions.Comment: To appear in Proceedings of the 6th International Conference on
Analysis of Images, Social Networks, and Texts (AIST'2017
Respiratory Syncytial Virus; Anti-viral immunity in humans and macaques.
The results presented in this thesis show that hRSV infection in humans results in a multifaceted immune response, which cannot be described as purely Th1- or Th2-like. However, the observed higher level of IL-13 producing hRSV-specific T cells in infants hospitalized with severe hRSV bronchiolitis could provide a clue for an immunopathological mechanism of natural hRSV-mediated severe disease. Another hRSV-specific immunological factor potentially involved in the pathogenesis of severe hRSV disease could be the frequency and/or phenotype like those of HLADP4-restricted T cell responses directed to the conserved region of the RSV G protein. The BBG2Na- and rMVA-F/G-based vaccination strategies evaluated in infant macaques resulted in low VN and cellular immune responses and no detectable protection. A combination of both approaches in a prime-boost regime could possibly increase vaccine immunogenicity, but in this case the immunopathological safety would again have to be evaluated in different animal models
Research Chimpanzees May Get a Break
A recent report by the Institute of Medicine leaves few urgent reasons standing for the continued use of chimpanzees in biomedical research. It is high time to think about their retirement, Frans de Waal argues, without neglecting prospects for non-invasive research on behavior, cognition, and genetics
3-methylhistidine as an Indicator for Protein Beakdown: An Experimental Model in Male Capra hircu
The role of the amino acid 3-methylhistidine as an indicator of protein breakdown and weight loss is often suggested. Despite existing information for other animal species, little is known about the actual levels of 3-methyhistidine in the serum of less studied domestic species such as the goat. We have evaluated the 3-methyhistidine serum concentrations in young Boer goat bucks subjected to two distinct feeding regimens: winter-grass hay with or without supplementation. Non-supplemented animals had a negative nitrogen balance and experienced weight loss throughout the experiment and significantly higher concentrations of 3-methyhistidine than supplemented animals that had a slight increase in live weight. This amino acid can be considered a valid indicator of protein breakdown and weight decrease in male goats. Serum 3-methylhistidine concentrations in adequately fed male goats were similar throughout the assay (20-40 μmol/l) whereas in weight-losing animals, concentrations of up to 170μmol/l can be expected.
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