Pair contact process with a particle source.

We study the phase diagram and critical behavior of the one-dimensional pair contact process (PCP) with a particle source using cluster approximations and extensive simulations. The source creates isolated particles only, not pairs, and so couples not to the order parameter (the pair density) but to a nonordering field, whose state influences the evolution of the order parameter. While the critical point p(c) shows a singular dependence on the source intensity, the critical exponents appear to be unaffected by the presence of the source, except possibly for a small change in beta. In the course of our paper, we obtain high-precision values for the critical exponents of the standard PCP, confirming directed-percolationlike scaling.

Significance of fever in Jamaican patients with homozygous sickle cell disease.

OBJECTIVE: To investigate the cause and outcome of high fever in Jamaican children with homozygous sickle cell disease. DESIGN: Retrospective review of febrile episodes in a three year period (1 September 1993 to 31 August 1996). SETTING: Sickle cell clinic, an outpatient clinic in Kingston run by the Medical Research Council Laboratories (Jamaica). PATIENTS: Patients with homozygous sickle cell disease under 17 years of age presenting with an axillary temperature >/= 39.0 degrees C (102.4 degrees F). MAIN OUTCOME MEASURES: Diagnosis, death. RESULTS: There were 165 events in 144 patients (66 (45.8%) boys) with a median age of 6.1 years. Bacteraemia was found in 10 (6.1%) events (three Streptococcus pneumoniae, two Haemophilus influenzae type b, two Salmonella sp, one Escherichia coli, one Enterobacter sp, and one Acinetobacter sp), and urinary tract infections in four (2.4%). All cultures of cerebrospinal fluid were sterile. Acute chest syndrome occurred in 36 (21.8%) events. A painful crisis was associated with 45 (27.3%) events and was the only pathology identified in 20 events (12.1%). Hospital admission was necessary in 66 cases including all those with bacteraemia and 31 with acute chest syndrome. There were two deaths: a 5 year old boy with septic shock associated with H influenzae septicaemia, and a 3 year old boy with the acute chest syndrome. CONCLUSIONS: Painful crisis and acute chest syndrome were the most common complications associated with high fever, but other important associated features included bacteraemia and urinary tract infection. Enteric Gram negative organisms accounted for 50% of positive blood cultures.

Marriage among lepers

One group of eleven carefully selected, strong and able-bodied couples in whom the disease was arrested were allowed to marry after vasectomy of the male, and to adopt a child and support themselves upon land within our colony. There have been no relapses of the disease after three years, and the experiment has proved a happy one. A second group with whose selection and marriage we had nothing to do came under our care. Among seventeen couples nine have had babies, and in four of the women concerned the disease has relapsed due to the strain of pregnancy and lactation. Lepers will marry, as do other people. RElapses follow and children are born who create new problems. For a limited number of selected suitable cases it seems to be highly desirable to permit marriage after sterilization and to aid these families in becoming self-supporting.

Sterilization and marriage of lepers

Certain selected inmates of our leper colony in whom the discase has been arrested have been allowed to choose mates. After they had built, with some assistance, houses for themselves on plots of land assigned to them, and after the males had been sterilized, they were married. Each couple was required to select from among the children of the colony one to adopt and bring up as their own. Those who entered this relationship did so voluntarily, and the experiment so far has been eminently sucessful. It has had a good effect upon all of the inmates of the colony, and has. reduced to one fourth the per capita cost of maintaining those concerned.