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

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

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

Fouling of heat exchanger surfaces by dust particles from flue gases of glass furnaces

Fouling by dust particles generally leads to a reduction of the heat transfer and causes corrosion of secondary heat exchangers. Α deposition model, including thermodynamic equilibrium calculations, has been derived and applied to describe the deposition (i.e. fouling) process and the nature of the deposition products in a secondary heat exchanger. The deposition model has been verified by means of laboratory experiments, for the case of flue gases from soda-lime glass furnaces. Corrosion of iron-containing metallic materials, caused by the deposition products, has been briefly investigated with the same equipment. There is a close similarity between the experimental results and model calculations. The largest deposition rates from flue gases on cylindrical tubes in cross-flow configuration, are predicted and measured at the upstream stagnation point. The lowest deposition rates are determined at downstream stagnation point locations. At tube surface temperatures of approximately 520 to 550 K, the fouling rate on the tube reaches a maximum. In this temperature region NaHSO4 is the most important deposition product. This component is mainly formed at temperatures from 470 up to 540 K. The compound Na3H(SO4)2 seems to be stable up to 570 K, for even higher temperatures Na2SO4 has been found. These deposition products react with iron, SO3, oxygen and water vapour forming the complex corrosion product Na3Fe(SO4)3. NaHSO4, which is formed at tube surface temperatures below 540 K, causes more severe corrosion of iron-containing materials than Na2SO4. Maintaining temperatures of the heat exchanger surfaces above 550 to 600 Κ reduces the fouling tendency and corrosion in case of flue gases from oil-fired soda-lime glass furnaces

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