Suppression of decoherence tied to electron-phonon coupling in telecom-compatible quantum dots: low-threshold reappearance regime for quantum state inversion.

We demonstrate suppression of dephasing tied to deformation potential coupling of confined electrons to longitudinal acoustic (LA) phonons in optical control experiments on large semiconductor quantum dots (QDs) with emission compatible with the low-dispersion telecommunications band at 1.3 µm. By exploiting the sensitivity of the electron-phonon spectral density to the size and shape of the QD, we demonstrate a fourfold reduction in the threshold pulse area required to enter the decoupled regime for exciton inversion using adiabatic rapid passage (ARP). Our calculations of the quantum state dynamics indicate that the symmetry of the QD wave function provides an additional means to engineer the electron-phonon interaction. Our findings will support the development of solid-state quantum emitters in future distributed quantum networks using semiconductor QDs.

Treatment of complicated urinary tract infection in adults: combined analysis of two randomized, double-blind, multicentre trials comparing ertapenem and ceftriaxone followed by appropriate oral therapy.

The efficacy and safety of parenteral ertapenem, a Group 1 carbapenem, 1 g once a day, for the treatment of complicated urinary tract infections (UTIs; i.e. acute pyelonephritis, UTI in men, or UTI associated with obstruction, foreign body or a urological abnormality interfering with normal voiding) in adults, were compared with those of parenteral ceftriaxone, 1 g once a day, in two similarly designed prospective, double-blind, randomized studies. In both studies, patients could be switched to an oral agent after > or = 3 days of parenteral study therapy. At entry, 850 patients were stratified according to whether they had acute pyelonephritis or other complicated UTI without acute pyelonephritis. Two hundred and fifty-six patients in the ertapenem group and 224 in the ceftriaxone group were microbiologically evaluable. Ninety-six per cent of these patients were switched to oral therapy, usually ciprofloxacin; the median (range) duration of parenteral and total therapy, respectively, was 4 (2-14) days and 13 (14-18) days for ertapenem and 4 (2-14) days and 13 (3-17) days for ceftriaxone. The most common pathogens were Escherichia coli and Klebsiella pneumoniae, which accounted for 64.7% and 9.8% of isolates, respectively. At the primary efficacy endpoint 5-9 days after treatment, 229 (89.5%) patients who received ertapenem and 204 (91.1%) patients who received ceftriaxone had a favourable microbiological response (95% confidence interval, -7.4 to 4.0), indicating that outcomes in the two treatment groups were equivalent. Success rates in both treatment groups were similar when compared by stratum and severity of infection. The frequency and severity of drug-related adverse events were generally similar in both treatment groups. In this combined analysis, ertapenem was highly effective therapy for the treatment of complicated UTIs in adults with moderate-to-severe disease.

Comparison of lumbar sagittal alignment produced by different operative positions.

STUDY DESIGN: This study is a prospective evaluation of the effects of commonly used spinal tables on lumbar sagittal alignment. OBJECTIVES: The objective was to determine the differences, if any, in lumbar sagittal alignment produced by different positions on routinely used spinal operating tables. SUMMARY OF BACKGROUND DATA: Earlier studies have documented the advantages of the knee-chest position in lumbar decompressive procedures. When simultaneous fusion is performed and augmented with internal fixation, intraoperative position is the critical determinant of sagittal plane balance. Other investigators have documented an association between the knee-chest position and decreased lumbar lordosis. METHODS: Ten asymptomatic volunteers underwent a series of four lateral lumbar radiographs, as follows: standing, prone on the Jackson (Orthopaedic Systems, Inc., Hayword, CA) spinal table, and prone on the Andrews (Orthopaedic Systems, Inc.) table with the hips flexed 60 degrees and 90 degrees, respectively. Intervertebral body angle measurements were obtained from L1 to S1. Lordosis values were compared and analyzed for each of the positions. Standing lordosis was assumed to be physiologic. RESULTS: Physiologic lordosis values were produced only on the Jackson operative table. Both positions on the Andrews table resulted in a statistically significant decrease in lumbar lordosis. Decreasing hip flexion on the Andrews table from 90 degrees to 60 degrees produced a statistically significant increase in lumbar lordosis. However, this change did not reproduce physiologic values. CONCLUSION: When instrumentation is used to augment lumbar fusions, positions incorporating hip flexion should be avoided to ensure maintenance of sagittal plane balance.

The history of yellow fever

An historical overview of yellow fever dating back to the 18th and 17th centuries. The author looks at the history of the first outbreak in Trinidad where Trinidad is specifically named in 1793. The paper highlights the key role that Trinidad has played in the unravelling of yellow fever epidemiological mysteries. Recorded and suspected outbreaks of yellow fever is also presented in table form

Jungle yellow fever mosquito studies in Trinidad: 1954

Eruption of a yellow fever epizootic/epidemic was signalled by the Trinidad Regional Virus Laboratory with the isolation of virus from the first human case in April 1954. Mosquito investigations were conducted in three major areas. Descriptions are provided of the forest environments, the mosquito collection techniques, transportation logistics, mosquito identification and isolation of viruses. An addendum briefly reviews subsequent yellow fever outbreaks in the island, addresses the question of origin and provides recommendations for the future.(AU)

The history of yellow fever

An historical overview of yellow fever dating back to the 18th and 17th centuries. The author looks at the history of the first outbreak in Trinidad where Trinidad is specifically named in 1793. The paper highlights the key role that Trinidad has played in the unravelling of yellow fever epidemiological mysteries. Recorded and suspected outbreaks of yellow fever is also presented in table form

Jungle yellow fever mosquito studies in Trinidad: 1954

Eruption of a yellow fever epizootic/epidemic was signalled by the Trinidad Regional Virus Laboratory with the isolation of virus from the first human case in April 1954. Mosquito investigations were conducted in three major areas. Descriptions are provided of the forest environments, the mosquito collection techniques, transportation logistics, mosquito identification and isolation of viruses. An addendum briefly reviews subsequent yellow fever outbreaks in the island, addresses the question of origin and provides recommendations for the future.

Monitoring for activity of arboviruses in Trinidad and Tobago

Paper covers the history and some of the operations of the Trinidad Regional Virus Laboratory

Monitoring for activity of arboviruses in Trinidad and Tobago

Paper covers the history and some of the operations of the Trinidad Regional Virus Laboratory

Jungle yellow fever mosquito studies in Trinidad: 1954

Eruption of a yellow fever epizootic/epidemic was signalled by the Trinidad Regional Virus Laboratory with the isolation of virus from the first human case in April 1954. Mosquito investigations were conducted in three major areas. Descriptions are provided of the forest environments, the mosquito collection techniques, transportation logistics, mosquito identification and isolation of viruses. An addendum briefly reviews subsequent yellow fever outbreaks in the island, addresses the question of origin and provides recommendations for the future (AU)

MR imaging of lumbar arachnoiditis.

To assess the usefulness of MR in defining the changes of lumbar arachnoiditis, we reviewed retrospectively the MR, plain-film myelographic, and CT myelographic findings in 100 patients referred for evaluation of failed-back-surgery syndrome. In 11 of 12 cases of arachnoiditis demonstrated by plain-film and CT myelography, an abnormal configuration of nerve roots was seen by MR. The correlated MR and CT and plain-film myelographic changes were divided into three anatomic groups: group 1 showed conglomerations of adherent roots residing centrally within the thecal sac, group 2 demonstrated roots adherent peripherally to the meninges giving rise to an "empty-sac" appearance, and group 3 demonstrated a soft-tissue mass replacing the subarachnoid space. There was one false-negative MR study. For the diagnosis of moderate to severe arachnoiditis, we found MR to correlate excellently with CT myelographic and plain-film myelographic findings.

Aedes aegypti strain fitness for yellow fever virus transmission

Three geographical strains of Aedes aegypti from Thailand (Amphur), East Africa (Kampala), and the West Indies (Santo Domingo) were compared for susceptibility to infection with low-passage yellow fever virus (French viscerotropic) as well as for ability to transmit virus by bite at varying extrinsic incubation periods. Santo Domingo strain appeared the most competent and Kampala the least when mosquitoes were exposed to a low level virus-infecting blood meal; at higher virus levels, a similar trend was noted but differences were less evident and in no case were the differences statistically significant. All three strains were infected with and transmitted yellow fever virus (AU)

Leptospirosis in Trinidad: further studies resulting in recognition of two new serotypes

Investigations on leptospirosis in Trinidad during the period 1962-1967, and characteristic of previously isolated leptospires are reported. Leptospires in the serogroups hebdomadis icterohaemorrhagiae, canicola, grippotyphosa and ballum were recognized to be present on the island. Two of the serotypes in the hebdomadis group, for which the names Trinidad and Tabaquite are proposed, were shown to be previously undescribed serotypes. The complement fixation test proven to be useful in recognizing leptospiral infection in humans. (AU)

Virus research facilities in Central and South America

Meeting of the Advisory Committee on Medical Research, 11. Pan American Health Organization; 19-23 Jun. 1972