A Modeling Procedure of the Broadband Dielectric Spectroscopy for Ionic Liquids.

The dielectric spectroscopy (DS) measurement is an attractive noninvasive method to reveal the intrinsic information of biological materials and cell cultures. However, the presence of a double layer due to electrode polarization within the lower RF and microwave range significantly affects the accurate analysis of dielectric properties of ionic liquids. In this paper, we measure the broadband DS of five saline solutions with a microfluidic coplanar waveguide (CPW) transmission line sensor across the frequency range from 40 kHz to 110 GHz. Derived from a parallel-plate structure that is transformed from the quasi-TEM CPW sensor through a conformal mapping technique, a broadband spectroscopy modeling method is proposed, where a Cole-Cole function or a constant phase element formula is used depending on the ionic concentrations and the measurement window. Validation analysis on the five saline solutions demonstrates the capability of the modeling method in separating relaxation properties of the bulk sample from the double-layer effects.

Cadaveric kidneys for transplantation. A paradox of shortage in the face of plenty.

The number of cadaveric kidneys currently available for transplantation is insufficient; therefore, the Center for Disease Control (CDC) undertook a collaborative pilot project to increase the number of cadaveric kidneys available for transplantation. In phase one, a retrospective review of medical records of in-hospital deaths was done to determine the potential number of cadaveric kidney donors and to define the characteristics of potential donors. The medical records of 10,420 (43.1%) of the 24,164 patients who died in 67 acute-care hospitals in Georgia, Kansas, and Missouri were retrieved. In addition to determining suitability for donorship, criteria were developed to reflect the broadest range of criteria in use. By center-specific criteria there were 1.7 potential donors/100 in-hospital deaths, which could make available 109 kidneys/million population. By broad intercenter criteria there were 3.5 potential donors/100 in-hospital deaths, which could provide 232 kidneys/million population. During 1975, by center-specific criteria, kidneys from 19.3% of the suitable potential donors were retrieved. The small number of transplantable cadaveric kidneys retrieved was not attributable to lack of suitable organs but rather the failure to identify suitable donors, obtain consent, and retrieve the kidneys.

Increasing the supply of cadaveric kidneys for transplantation.

The number of cadaveric kidneys currently available for transplantation is insufficient. Therefore, the Center for Disease Control (CDC) undertook a collaborative project with the two transplant programs in Georgia to increase te retrieval of cadaveric kidneys. We used retrospective analysis to select productive hospitals, hospital-specific surveillance systems to identify potential donors, and procurement and retrieval evaluation to identify preventable deficiencies. During 900 hospital months of prospective surveillance, we identified a total of 555 potential donors by death record review, giving a potential donor rate of 2.3 donors/100 deaths (110 kidneys/million population/year). We observed an increase in the number of referrals, consent obtained from next of kin, and kidneys retrieved. This period of intensive activity demonstrated that additional kidneys can be retrieved by using systematic methods.

Health impact of measles vaccination in the United States.

As a result of intensive efforts to vaccinate children, measles and its attendant complications of encephalitis and death have declined more than 99% from the prevaccine era. Similarly, subacute sclerosing panencephalitis has declined markedly. Measles vaccine has been demonstrated to be extremely safe, as well as extremely effective. The health and resource benefits due to vaccination against measles during the first 20 years of vaccine licensure have been enormous. In this period it is estimated that vaccination against measles has prevented 52 million cases, 5,200 deaths, and 17,400 cases of mental retardation, achieving a net savings of $5.1 billion. These substantial health and resource benefits of measles vaccination will continue to accrue in the future.

Vaccine-preventable disease and immunization in the developing world.

Vaccines have given health care providers control over a substantial portion of the morbidity and mortality in the developing world. Global efforts have immunized two-thirds of the world's children with DTP and polio vaccines; 72% have received BCG and 59% measles vaccine; but only 29% of pregnant women have received two doses of tetanus toxoid. In addition, vaccines against yellow fever, Japanese encephalitis, hepatitis B, rubella, and mumps and meningococcal polysaccharide vaccine are being used in specific regions of the world. New vaccine candidates will enhance the vaccine armamentarium over the next decade to include the causes of pneumonia, diarrhea, and meningitis: Haemophilus influenzae type b, pneumococcal and meningococcal protein conjugate vaccines, typhoid and rotavirus vaccine. Genetically engineered vaccine vehicles, genetic reassortants, and genetic deletions are being investigated as new vaccine candidates.

Single solution for oral therapy of diarrhoea.

PIP: Questions about the suitability of a single oral electrolyte solution containing 90 mmol/liter of sodium for rehydration therapy in diarrhea are raised because of the possibility of repeating the experience of 30 years ago in the U.S. when widespread use of electrolyte solutions and commercial milk preparations resulted in the so-called era of hypertonicity. Given that most diarrhea cases requiring rehydration occur in developing countries where nutrition is questionable and given that even in developing countries hypernatremia occurs too frequently, the letter writers argue that the single formulation of an oral therapy solution may be ill-advised. Studies on oral fluid therapy have been carried out in children over 2 years of age in developing countries, and it was found that children with underlying hypertonicity secondary to high solute artificial feedings were pushed to the fringe of their extracellular-volume and renal-function tolerances. The letter writers argue for further studies of the suitability of such a high sodium concentration in the electrolyte solution and feel that a mixture with a lower sodium concentration in the under 2 age group in developing countries is more suitable.^ieng

Global eradication of poliomyelitis: benefit-cost analysis.

A benefit-cost analysis of the Poliomyelitis Eradication Initiative was undertaken to facilitate national and international decision-making with regard to financial support. The base case examined the net costs and benefits during the period 1986-2040; the model assumed differential costs for oral poliovirus vaccine (OPV) and vaccine delivery in industrialized and developing countries, and ignored all benefits aside from reductions in direct costs for treatment and rehabilitation. The model showed that the "break-even" point at which benefits exceeded costs was the year 2007, with a saving of US$ 13 600 million by the year 2040. Sensitivity analyses revealed only small differences in the break-even point and in the dollars saved, when compared with the base case, even with large variations in the target age group for vaccination, the proportion of case-patients seeking medical attention, and the cost of vaccine delivery. The technical feasibility of global eradication is supported by the availability of an easily administered, inexpensive vaccine (OPV), the epidemiological characteristics of poliomyelitis, and the successful experience in the Americas with elimination of wild poliovirus infection. This model demonstrates that the Poliomyelitis Eradication Initiative is economically justified.

The virtual elimination of rubella and mumps from the United States and the use of combined measles, mumps and rubella vaccines (MMR) to eliminate measles.

The measles elimination effort, which began in 1978, has made dramatic contributions to the virtual elimination of rubella and congenital rubella syndrome (CRS) and the control of mumps in the USA. The use of combined MMR vaccine has resulted in immunization levels at school entry in excess of 95% against each of these diseases. As a result, record low levels of rubella, CRS, and mumps were reported in 1984. Continued use of MMR, along with improved surveillance and aggressive response to outbreaks, can be expected to eliminate rubella and mumps as well as measles.

Isolation of Vibrio cholerae from nightsoil during epidemics of classical and E1 Tor Cholera in East Pakistan.

A clear difference has been observed between the classical Inaba V. cholerae and the El Tor Ogawa V. cholerae in relation to the ability to isolate the organism from the environment.An early attempt to utilize nightsoil sampling as a tool to measure the extent of infection in the community during an epidemic of classical Inaba cholera in Dacca, East Pakistan, in the spring and fall of 1968 proved unsuccessful. During an epidemic caused by both the classical Inaba and the El Tor Ogawa vibrios in Chittagong between July 1968 and March 1969 the reasons for this failure became apparent. In Dacca, only 2 isolations of classical Inaba were made from 9906 individual latrine and pooled communal nightsoil samples, whereas in Chittagong, from 62 588 similar samples in which 2 classical Inaba isolations were also made, there were 52 El Tor Ogawa isolations. In areas where cases due to both biotypes were occurring simultaneously, El Tor Ogawa vibrios were isolated 10 times more frequently than the classical Inaba.It remains unclear whether the differences observed between El Tor Ogawa and classical Inaba are related to the biotype or to the serotype of the organism, or to both. An extrapolation of nightsoil sampling, therefore, to the incidence and prevalence of infection in a community must consider both the biotype and the serotype.