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During processing of ready-to-eat (RTE) deli meats, any secondary processing procedures such as peeling and cutting introduce the distinct possibility of cross-contamination between equipment, personnel, and food. To eliminate or reduce pathogens such as Listeria monocytogenes and ensure food safety, RTE deli meats can be pasteurized prior to or after packaging. In this study, ambient steam in-package pasteurization was compared with pressurized steam prepackaging pasteurization to reduce L. monocytogenes from fully cooked RTE bologna. The bologna (14 cm diameter×1.5 cm thickness) samples were surface-inoculated to contain about 8 log 10 of L. monocytogenes . To achieve 2 log reductions for L. monocytogenes , the bologna samples needed to be treated for about 10 s in pressurized steam at 131 °C or for about 2.5 min in ambient steam at 100 °C. The pasteurization time using pressurized steam treatment was about 75–90% shorter than using ambient steam treatment. Pressurized steam treatment may be integrated into a vacuum packaging unit to effectively eradicate L. monocytogenes from RTE meats just prior to sealing the retail packages to further reduce the treatment time, avoid post-treatment recontaminations by pathogens, and improve food safety without detrimentally affecting meat quality.

Background: The addition of droperidol to morphine for patient-controlled analgesia reduces the incidence of nausea and vomiting, but may result in unwanted side effects. Method: We studied 40 women randomised to receive morphine sulphate with or without added droperidol (10mg droperidol/60mg morphine) by patient-controlled analgesia following elective caesarean section under spinal anaesthesia. Results: Median morphine demand in the 20h after surgery was 74mg with morphine alone, and 53mg with added droperidol, the median consumption of which was 8.8mg. The incidence of nausea was reduced from 80% to 38.8% (P

Cerebral oximetry was evaluated as a monitor of oxygenation during carotid endarterectomy in 22 patients. The oximeter was a reliable continuous monitor, identifying changes in cerebral oxygenation during episodes of hypotension and after arterial occlusion. Changes in oxygenation correlated well with the surgical assessment of backbleeding after arterial clamping, but less well with other methods which are used to make a decision on insertion of an arterial shunt. There was no correlation between internal carotid artery stump pressure and change in cerebral oxygenation after application of the arterial cross clamp. However, cerebral oxygenation correlated weakly with the change in middle cerebral artery velocity as measured by transcranial Doppler ultrasonography (r = 0.49, p < 0.02).

Most girls go through puberty with awareness of their sexuality and recognition of the physical changes but with little concern for the details such as onset or rate of progress. Some girls and most mothers are not eager for sexual maturity and recognition of delay is late, unless there are complicating features. Diagnosis of delay and its cause may require careful observation over several months and judicious selection of appropriate tests. It is important not to jump to conclusions which may be wrong. Identification of the occasional serious cause is important since harm may result from delay. Recognition of constitutional delay from long-term causes of hypogonadotrophic hypogonadism may be difficult and replacement treatment may be advisable to gain oestrogen benefits with deferment of final diagnosis. Where there is a fundamental defect of the ovaries or genital tract which will prevent fertility, the condition must be communicated with sensitivity but without ambiguity. Conditions which are reversible so far as pubertal development is concerned require accurate diagnosis and, usually, long-term management.

A computer model simulating the formation of an artificially ionized layer in the atmosphere by a series of microwave pulses was developed and is presented. The approach utilizes possible opportunities offered by the existing Arecibo transmitter and antenna. A modified version of the kinetic theory of the breakdown of air by a powerful microwave emission was incorporated into a model of electromagnetic propagation through the atmosphere by a converging ionizing microwave pulse. This model takes into consideration radio wave self-action as well as absorption, and produces profiles of electron concentration formed in the atmosphere by both an isolated pulse and a series of pulses. Effects of varying the shape of the ionizing pulse are considered as well as the influence of the ambient electron concentration. Also, the dependence of the electron concentration on the energy and duration of the pulse is investigated. The possible increase in the rate of electron production is considered when using an intense pulse to initiate the breakdown followed by a series of pulses of lesser energy. The influence of the refraction of the microwave beam is estimated. The computer model presented shows that an AIL (Artificial Ionized Layer) of electrons reaching concentrations on the ordermore » of 10{sup 8} cm{sup {minus}3} Could be formed over a height range of 40--70 km, if the Arecibo antenna and radio facility were reconfigured so that it would be able to generate microwaves with f = 2.38 GHz and a power of approximately 1--4 MW. In addition, a pulse compressor would be used to form pulses with durations of approximately 0.1--0.15 {mu}s with a repetition frequency of 103 Hz.« less

The salient features of the sidebands generated on the HF waves in an ionospheric plasma modified by two pump frequencies are presented and compared to theories. Particular attention is focused upon the properties of the nonlinear modulation process by comparing the modulation index theory and the observations. The observations show that the amplitudes of the sidebands are related to the HF power and the difference frequency of the two pump waves. The relationships of the amplitude of the sideband with HF frequency, the scale height, and the temperature of the electrons in the ionosphere are discussed. The modulation index theory shows agreement with the observations over a range of conditions.

Surface pasteurization by applying steam or hot water before or after packaging of processed foods may be used to eliminate pathogens such as Listeria monocytogenes from ready-to-eat meat and poultry products. Surface pasteurization treatment with a mixture of pressurized steam and hot water was integrated into a continuous vacuum-packaging system to reduce L. monocytogenes from fully cooked franks. The franks (2.54 cm diameter by 15.24 cm length) were surface inoculated to contain up to 6 log CFU/cm2 L. monocytogenes. The inoculated franks were treated at 121 degrees C for 1.5 s in an arrangement of six franks per packaging chamber followed by immediate vacuum sealing of the top films of food packages in the same unit. A 3-log CFU/cm2 reduction of L. monocytogenes on fully cooked franks was obtained using the integrated pasteurization-packaging system. The pasteurization depth was 1.27 mm below the surfaces of the franks. This process provides a commercially applicable means of ensuring food safety by effectively eradicating L. monocytogenes from ready-to-eat meat and poultry products at the very last possible step of food packaging before reaching retail consumers.

Commercially formulated meat products, including chicken patties, chicken tenders, franks, beef patties, and blended beef and turkey patties, were obtained from processors. Each product was inoculated with 7 to 8 logs of Salmonella (Senftenberg, Typhimurium, Heidelberg, Mission, Montevideo, and California) or Listeria innocua. The inoculated meat samples were heat treated at 55 to 70 degrees C. At each temperature, the decimal reduction time (D) was obtained by linear regression of survival curves. Values of D and the temperature difference required for the thermal inactivation curve to drop a logarithmic cycle (z) were determined for the Salmonella serotypes and L. innocua in each product. At 55 to 70 degrees C. for the five tested products, the D-values for the Salmonella serotypes and L. innocua were 26.97 to 0.25 min and 191.94 to 0.18 min, respectively, and their z-values were 7.60 to 9.83 degrees C and 4.86 to 8.67 degrees C, respectively. Significant differences were found for the D- and z-values among the five products. This study will better enable processors to determine the process lethality of pathogens in commercial meat products.

We have compared intermittent bolus and continuous infusion of extradural local anaesthetic for pain relief in a randomized, double-blind study of 48 patients who underwent major abdominal gynaecological surgery. Each patient received 5 ml of 0.375% bupivacaine hourly, either as a bolus over 5 min or as a constant infusion. Patients who received the intermittent administration technique maintained a more extensive sensory block, reported marginally better analgesia and had a lower requirement for rescue medication. The intermittent bolus technique was not associated with an increase in side effects.

PURPOSE To determine the effects of sargramostim (recombinant human granulocyte-macrophage colony-stimulating factor [rhu GM-CSF]) on the incidence, duration, and complications of myelosuppression after moderate-dose fluorouracil, doxorubicin, cyclophosphamide (FAC) adjuvant chemotherapy in patients with node-positive breast cancer. PATIENTS AND METHODS In this randomized, double-blind, placebo-controlled study, 142 women with stage II and III breast cancer were to receive four 21-day cycles of chemotherapy that consisted of fluorouracil 600 mg/ m2 intravenously (IV), doxorubicin 60 mg/m2 IV, and cyclophosphamide 750 mg/m2 IV on day 1, followed by placebo or GM-CSF 250 micrograms/m2/d daily subcutaneously (SC) on days 3 through 15. All patients received prophylactic ciprofloxacin by mouth when the absolute neutrophil count (ANC) was less than 1,000/microL. RESULTS Eighty-six percent of GM-CSF patients (n = 62) and 96% of placebo patients (n = 69) completed four assessable cycles of treatment on study. Overall, the median duration of severe neutropenia (ANC < 500/microL) was 2.8 days with GM-CSF and 6.8 days with placebo (P < .001); the duration of ANC less than 1,000/microL was 6.0 versus 9.1 days, respectively (P < .001). Hospitalizations for febrile neutropenia were uncommon in either group: GM-CSF, six; placebo, eight. The only other difference in hematologic toxicity was grade 3/4 thrombocytopenia observed with greater frequency in GM-CSF patients than placebo patients in cycles 3 and 4. GM-CSF increased mean the FAC dose-intensity among patients who completed two or more cycles (P < .001). GM-CSF was generally well tolerated and associated with more injection-site reactions, but less mucositis than placebo. There were no deaths on study. CONCLUSION GM-CSF significantly enhanced ANC recovery after FAC chemotherapy; it decreased the incidence and duration of associated neutropenia and moderately increased the dose-intensity of adjuvant chemotherapy. Whether these effects will ultimately translate into improved long-term outcome remains to be determined.

Caesarean section is associated with significant cardiovascular disturbances. We present a patient known to have a large pelvic arteriovenous malformation who underwent elective Caesarean section. To assist in the monitoring and management of the anticipated haemodynamic changes a flow directed pulmonary artery catheter with the capacity to allow continuous cardiac output measurement was used.

Objective— To compare the frequency of common antenatal problems, the amount of antenatal surveillance and the obstetric and neonatal outcome in women with and without a history of infertility. Design— A prospective cohort study with age and parity matched controls. Setting— A single consultant unit at the Jessop Hospital for Women, Sheffield, over a 22-month period. Subjects— 114 women with a history of infertility who reached 16 weeks gestation with a singleton live fetus and 114 control women matched for age and parity. Main outcome measures— Frequency of antepartum, complications, amount of antepartum surveillance, obstetric and neonatal outcome. Results— Common antenatal complications were not increased. In the infertility compared with the control group, the relative risk of requiring an emergency caesarean section was 2.43 (95% CI 1.05–5.63). There was no difference in birthweight. Conclusion— Many of the previously observed differences in outcome of pregnancy in women after infertility compared with those without are associated with age and parity but these characteristics do not explain the increased frequency of emergency caesarean section.

Sixty six women with first or second trimester fetal loss were investigated for the presence of lupus anticoagulant by routine coagulation tests and the dilute Russell's viper venom time with a platelet neutralisation procedure, and for raised anticardiolipin antibodies by an enzyme linked immunosorbent assay. Of 35 women with recurrent fetal loss, seven were positive for lupus anticoagulant and six had increased IgG anticardiolipin antibodies, while of 31 women with only one or two episodes of fetal loss, one had lupus anticoagulant and none increased IgG anticardiolipin antibodies. These findings were significantly different. There was no difference in the incidence of increased IgM anticardiolipin antibodies between the two groups (three and two cases, respectively). A further 11 women with intrauterine death in the third trimester were studied and lupus anticoagulant and raised IgM anticardiolipin antibodies were found in one case. No woman was known to have systemic lupus erythematosus. It is concluded that lupus anticoagulant and increased IgG anticardiolipin antibodies are independently associated with recurrent first and second trimester fetal loss and that such cases should be investigated, even in the presence of otherwise good health, by a comprehensive methodological approach.

The Ionospheric Focused Heating rocket was launched on May 30, 1992. The sounding rocket carried an instrument and chemical payload along a trajectory that crossed the intersection of the beams from the 430-MHz incoherent scatter radar and the 5.1-MHz high-power radio wave facility near Arecibo. The release of 30 kg of CF{sub 3}Br into the F region at 285 km altitude produced an ionospheric hole that acted like a convergent lens to focus the HF transmission. The power density inside the radio beam was raised by 12 dB immediately after the release. A wide range of new processes were recorded by in situ and ground-based instruments. Measurements by instruments flying through the modified ionosphere show small-scale microcavities (< 1 m) and downshifted electron plasma (Langmuir) waves inside the artificial cavity, electron density spikes at the edge of the cavity, and Langmuir waves coincident with ion gyroradius (4 m) cavities near the radio wave reflection altitude. The Arecibo incoherent scatter radar showed 20 dB or greater enhancements in ion acoustic and Langmuir wave turbulence after the 5.1-MHz radio beam was focused by the artificial lens. Enhancements in airglow from chemical reactions and, possibly, electron acceleration were recorded with optical instruments. Themore » Ionospheric Focused Heating experiment verified some of the preflight predictions and demonstrated the value of active experiments that combine high-power radio waves with chemical releases. 30 refs., 14 figs., 1 tab.« less

In June 1992 a NASA sponsored sounding rocket was flown through the Arecibo heater beam to study the structure of the heated volume. The rocket carried an instrument payload and traversed the 5.1-MHz reflection height at 268.5 km. Data from the plasma density probe are presented in this paper. The rocket passed through several regions of disturbed plasma both above and below the reflection level. In these regions, over 180 deep filamentary density depletions were detected. Measured perpendicular to the magnetic field, these depletions or filaments have a mean width at half maximum of 7 m which is roughly equal to twice the ion gyroradius (O + ) and a mean depletion depth of 6%. The ratio of parallel to perpendicular scale for these structures exceeds 20,000, and the spacing between the filaments is around 15 m. A power spectrum of the rocket data clearly shows the spectral content of the filaments and also reveals peaks at longer wavelengths which we interpret as the spacing between the bunches and between sets of filaments within a given bunch. We believe that previous scintillation and satellite measurements emphasized these longer wavelengths. The power spectrum measured by the rocket instrumentation falls off as k −4 for wavenumber k larger than 0.4/m and remains above the system noise for structure down to 1 m. It is clear that VHF backscatter from these structures can be explained by our data, as can many features of heater-related, field-aligned irregularities found in the literature.

This paper describes a two-dimensional computer model of the mesosphere/thermosphere/ ionosphere, which was designed for the analysis of F-layer depletions produced by rocket launches. Model results are compared with ionospheric data from May 1973, before and after the launch of Skylab I. They are also compared with more extensive data taken in conjunction with the September 1979, launch of HEAO-C. Our own experimental observations of the HEAO-C launch are also described. These include optical measurements of O(1D) airglow and incoherent scatter measurements with the Arecibo radar.

Uterine activity was measured quantitatively during subsequent labor after prostaglandin E2 gel (PGE2). Thirty primigravidae with a low Bishop score were included in this randomized double-blind study. Fewer women who received PGE2 required subsequent surgical induction. The pattern of uterine activity was different. Cervical dilatation was achieved with less uterine activity in the PGE2 group, especially during the shorter latent phase.

The oil crisis in the early seventies stimulated an intensive search for energy alternatives. Among the alternatives proposed for the long range (year 2000 and beyond) as a source of base load electric power is P. Glaser's solar power satellite. In a bold concept, Glaser proposed collecting solar energy on a geosynchronous satellite and relaying it by a microwave beam to a large collector on the ground. The concept in principle is feasible but requires a number of advances in technology to make it cost competitive and raises some questions about the effects of microwave radiation and the impacts on telecommunications. We propose to describe the concept, outline the problems it raises, treat the telecommunications problems with care, and comment generally on the problems of dealing with a bold proposal to solve, in part, a major problem facing society.

Plasma fluid equations describing concentration, velocity and temperature are coupled to the nonlinear wave equation in a numerical model of F-region heating by high power radio waves. Self-focusing of radio waves is calculated for plane waves and beams propagating in an underdense ionosphere. Ponderomotive forces are found to be negligible in comparison with thermal forces for self-focusing in the ionosphere. The structure of plasma irregularities near focal points is determined by diffraction of the radio waves.

Summary Severe pre-eclampsia leading to fetal death in advanced abdominal pregnancy is reported. Attention is drawn to the low reported incidence of pre-eclampsia in this condition and possible explanations are put forward.

Intense HF-radiowaves of the ordinary mode transmitted from the ground enhance plasma waves near the reflection height. These have been extensively studied in the past by the use of Incoherent-Scatter-Radars. Intense HF-radiowaves propagating in the ionosphere also produce electron density irregularities with scale sizes much larger than the HF wavelength of ∼ 60 m. These have been observed by radio star intensity scintillations. For the past 2 years a new method was used at Arecibo, P.R. which allows radar- and scintillation-measurements at 430 MHz to be performed simultaneously along the same line of sight. The scale sizes deduced from the scintillation measurements are shorter than the scale sizes observed with the radar and are inconsistent with the HF-power density thresholds predicted by existing theories.

The value of routine regular antenatal cardiotocography (CTG) in the management of high-risk pregnancy was assessed in a prospective randomized controlled study of 353 patients. All patients had a weekly CTG trace during the last 6 weeks of pregnancy and according to the random allocation the tracings were concealed from, or available to, the clinicians. Other methods of assessing fetal welfare were available to both groups. There was no significant difference between the concealed and revealed groups in the timing and mode of delivery, birthweights, Apgar score and neonatal morbidity. No apparent effect from the routine use of antenatal CTG in high-risk pregnancy was shown.

A new technique is used to measure F region plasma drifts at night. The technique involves observing the motion of density cavities generated by high-power radio waves in the ionosphere. The airglow signature of the cavities is recorded and analyzed with a ground-based, low-light-level imaging system. The heater-induced cavity optical tracer method is capable of providing velocity information with an error less than 1 m/s and a time resolution better than 60 s.

Six further cases of acute fatty liver of pregnancy are presented and discussed in relation to the world literature on this rare disease of pregnancy, the aetiology of which is still unknown. The importance of vomiting in late pregnancy is emphasized. A common feature seems to be a metabolic stress, possibly related to infection, which tips a susceptible liver into metabolic failure.

It has now become technologically feasible to construct ground-based HF radar systems which can deliver RF energy to the ionospheric plasma, with power densities sufficient to alter the ionospheric electron thermal budget and plasma characteristics. Effects produced by a ground-based transmitter of a power aperture of the order of 10,000 Mw sq m in the frequency range from 4 to 12 MHz are shown in a graph. Another graph presents a profile of electron gas temperature enhancement due to energy deposition by a high power HF transmitter. The conduction of high-power HF ionospheric plasma experiments is discussed. Attention is given to plasma instabilities, wave-particle acceleration effects, spacial and time scales, parametric instabilities, spread-F, and the possibility of placing high power-aperture radars on an orbiting space platform.

Between 1974 and 1985 16 pregnant women at high risk of foetal loss due to Rhesus isoimmunization received antenatal plasma exchange with 4.5% human albumin solution once or twice weekly throughout the second trimester until delivery, usually at 28–29 weeks. Overall foetal survival was 75% (92% since 1980). Of 11 children followed for up to 4 yr, development is entirely normal in 7. Two have had periods of dystonia, and two others have had delay in language development and motor skills respectively, but all four are improving. Immunoglobulins were replaced by human intramuscular immunoglobulin, thus avoiding the allergenic and viral hazards of fresh frozen plasma. Although direct intravascular transfusion may eventually supercede plasma exchange, the regime described here can produce good overall quality of long-term outcome for selected patients.

An analytical model for the effects of rapid annealing in narrow base bipolar transistors has been developed. This model utilizes transistor base-emitter voltage and an empirical curve to calculate annealing factor with time. The model has been incorporated into the TRAC circuit analysis code and used to predict the time-dependent response of a low-power Schottky TTL NAND gate and a four-bit shift register as a function of neutron fluence and operating condition.

Function of the pituitary-adrenal axis was assessed in 16 adult female patients who had been taking cyproterone acetate for greater than 1 year. Some evidence of reduced basal cortisol output was seen in 25% of the patients, but plasma cortisol levels could be stimulated both by hypoglycaemia and by direct corticotrophin (ACTH) stimulation. The latter effect was confirmed by analysis of steroid excretion in urine although basal excreation rates indicated extensive adrenal suppression. These results suggest that cyproterone acetate does have some glucocorticoid activity which is able partially to suppress the pituitary--adrenal axis, but leaves it still responsive to stress.

SummaryThere is currently both an absolute and relative reduction in births to older women. In a single hospital population the number of older women. In a single hospital population the number of older women having amniocentesis for pre-natal diagnosis is only a small, though increasing, proportion of those at risk. The main factors in failure of offering amniocentesis are late booking and communication difficulty.

The response of the ionospheric plasma to multiple pumps is seen in the enhancements of the incoherent scatter plasma line. Two strong HF pumps are transmitted, along with weaker sidebands. The two main pumps have a frequency separation ranging from 0 to 7 kHz. At zero frequency separation the standard decay and purely growing mode instabilities are observed. When two pumps are present, the normal decay instability usually disappears, and is replaced by strong oscillations at the pump frequencies plus features half way between pairs of pumps. These "arithmetic mean" peaks appear in most of the cases observed. The weak transmitted sidebands seem to influence greatly the observed spectra; the theory is treated in a companion paper.

The blood flow through the hands, feet, calf of the leg, and forearm is essentially the same during pregnancy and the puerperium in normal women, and in women with mild or severe toxaemia of pregnancy or essential hypertension. The resistance to flow of blood through the limbs is, however, raised.

1. In foetal lambs, delivered by Caesarean section under light chloralose anaesthesia, injection of sodium cyanide into the left atrium or ascending aorta caused a rise of arterial pressure and femoral vasoconstriction. The response to 0·77 mg/kg was barely present at 0·6 of term; by 0·8 of term there was a large response to one third of this dose. 2. The cardiovascular response to cyanide injection into the left atrium or ascending aorta was diminished either by section of the vagi or by carotid denervation, and was abolished by cutting both sets of nerves. 3. Injection of sodium cyanide into both common carotids simultaneously caused a substantial cardiovascular response and often a respiratory effort, abolished by carotid denervation, whereas injection into a single carotid rarely caused an effect. 4. It is concluded that the carotid chemoreceptors in mature foetal lambs can be excited by a stimulus of sufficient intensity, even though they do not respond to moderate hypoxaemia.

This article reviews literature on the effects of volume expansion in pre-eclampsia, concerning the risks of pulmonary oedema and hypertension, and the quality of placental perfusion