Quantum Nondemolition Measurement of a Quantum Squeezed State Beyond the 3 dB Limit.

We use a reservoir engineering technique based on two-tone driving to generate and stabilize a quantum squeezed state of a micron-scale mechanical oscillator in a microwave optomechanical system. Using an independent backaction-evading measurement to directly quantify the squeezing, we observe 4.7±0.9 dB of squeezing below the zero-point level surpassing the 3 dB limit of standard parametric squeezing techniques. Our measurements also reveal evidence for an additional mechanical parametric effect. The interplay between this effect and the optomechanical interaction enhances the amount of squeezing obtained in the experiment.

Thermally induced parametric instability in a back-action evading measurement of a micromechanical quadrature near the zero-point level.

We report the results of back-action evading experiments utilizing a tightly coupled electro-mechanical system formed by a radio frequency micromechanical resonator parametrically coupled to a NbTiN superconducting microwave resonator. Due to excess dissipation in the microwave resonator, we observe a parametric instability induced by a thermal shift of the mechanical resonance frequency. In light of these measurements, we discuss the constraints on microwave dissipation needed to perform BAE measurements far below the zero-point level.

The Advanced LIGO photon calibrators.

The two interferometers of the Laser Interferometry Gravitational-wave Observatory (LIGO) recently detected gravitational waves from the mergers of binary black hole systems. Accurate calibration of the output of these detectors was crucial for the observation of these events and the extraction of parameters of the sources. The principal tools used to calibrate the responses of the second-generation (Advanced) LIGO detectors to gravitational waves are systems based on radiation pressure and referred to as photon calibrators. These systems, which were completely redesigned for Advanced LIGO, include several significant upgrades that enable them to meet the calibration requirements of second-generation gravitational wave detectors in the new era of gravitational-wave astronomy. We report on the design, implementation, and operation of these Advanced LIGO photon calibrators that are currently providing fiducial displacements on the order of 10-18m/Hz with accuracy and precision of better than 1%.

Bacterial endocarditis in a patient with mitral valve prolapse.

Bacterial endocarditis developed following dental manipulation in a child with mitral valve prolapse. Antibiotic prophylaxis is recommended for patients with this cardiac abnormality who undergo procedures that may be associated with bacteremia.

QUANTUM MECHANICS. Quantum squeezing of motion in a mechanical resonator.

According to quantum mechanics, a harmonic oscillator can never be completely at rest. Even in the ground state, its position will always have fluctuations, called the zero-point motion. Although the zero-point fluctuations are unavoidable, they can be manipulated. Using microwave frequency radiation pressure, we have manipulated the thermal fluctuations of a micrometer-scale mechanical resonator to produce a stationary quadrature-squeezed state with a minimum variance of 0.80 times that of the ground state. We also performed phase-sensitive, back-action evading measurements of a thermal state squeezed to 1.09 times the zero-point level. Our results are relevant to the quantum engineering of states of matter at large length scales, the study of decoherence of large quantum systems, and for the realization of ultrasensitive sensing of force and motion.

Granulomatous mediastinitis due to Aspergillus flavus in a nonimmunosuppressed patient.

A patient with granulomatous mediastinitis due to Aspergillus flavus is described. A 22 year old black man presented with cough, fever and a right hilar mass. Mediastinal biopsies revealed granulomatous fibrosing mediastinitis with fungal elements compatible with aspergillus species. A flavus was isolated on culture of this material and later from sputum and bronchial washings. Studies of the patient's immune status revealed normal humoral and cellular immunity. No underlying neoplasm was found. The patient was treated with amphotericin B and 5-fluorocytosine but esophageal and superior vena caval compression developed and he died. This is the first reported case of granulomatous mediastinitis due to A. flavus in a patient whose immune responses were not suppressed (nonimmunosuppressed patient). Infection with Aspergillus species should be considered in the differential diagnosis of granulomatous mediastinitis.

The cephalosporins: activity and clinical use.

The cephalosporin antibiotics have been employed with increasing frequency since their introduction into clinical practice in the early 1960s. With the exception of cephaloridine, cephalosporin compounds are not associated with the production of significant untoward effects. The availability of newer cephalosporins, both oral and parenteral, with enhanced antibacterial activity, has expanded the clinical indications for administration of these antibiotics.

Treatment of bacterial infections in pregnancy.

Treatment of bacterial infections in pregnancy requires an understanding of the unique problems related to the administration of antibacterial agents to pregnant women. The clinician must be aware not only of the antibiotic-associated untoward effects which may develop in the mother, but also of the possibility that adverse reactions may occur in the fetus. Precise knowledge of the microbial aetiology of those infections which occur during pregnancy and an understanding of the intricacies of antibiotic administration to pregnant women will assure the greatest likelihood that bacterial infections in pregnancy will be effectively, and safely, treated.

Listeria monocytogenes endophthalmitis.

Listeria monocytogenes and a staphylococcus organism caused a catastrophic endophthalmitis in a patient despite appropriate local and systemic antimicrobial chemotherapy. Although L monocytogenes is widespread in nature and has produced a variety of clinical illnesses, it has only one previously been reported to cause endophthalmitis. If appropriate microbiologic techniques are not employed, the organism may go unrecognized as an ocular pathogen.

Bilateral emphysematous pyelonephritis.

Emphysematous pyelonephritis is a severe infection found almost exclusively in diabetics, characterized by the presence of gas within the renal parenchyma. The diagnosis is established radiographically. An additional case is added to the 52 cases reported in the literature; we believe this is the fifth reported case with bilateral emphysematous pyelonephritis. If appropriate diagnostic studies demonstrate no evidence of either perinephric abscess or urinary obstruction, intensive medical management should be the initial therapy for this condition. Surgical intervention is necessary in patients without prompt response to medical therapy.

Resection of intraocular squamous cell carcinoma.

A patient with recurrent squamous cell carcinoma of the conjunctiva was referred with 20/20 vision in an eye with obvious intraocular extension. A modified iridocyclochoroidectomy was performed and the tumour was removed. Three and a half years later the patient's vision is 20/30 and there is no recurrence. This is the first case in which an eye has been successfully salvaged with documented intraocular squamous cell carcinoma of the conjunctiva.

Efficacy of diclofenac sodium ophthalmic solution versus placebo in reducing inflammation following cataract extraction and posterior chamber lens implantation.

One hundred forty-eight patients were enrolled in a randomized, prospective, placebo-controlled clinical trial evaluating the efficacy of diclofenac sodium (Voltaren Ophthalmic) in reducing ocular inflammation following extracapsular cataract extraction with posterior chamber intraocular lens implantation. Eligible patients were enrolled and randomized (2:1 diclofenac:placebo) if the sum of anterior chamber cells plus flare one day postoperatively (baseline) was at least four. None of the patients received concomitant steroidal anti-inflammatory treatment. The 99 patients receiving diclofenac sodium had significantly greater improvement from baseline in summed flare plus cell score than the 49 placebo patients at two to five days and seven to nine days after baseline. Similarly, diclofenac sodium patients had significantly less post-baseline conjunctival erythema and ciliary flush than placebo patients. Significantly more diclofenac sodium patients than placebo patients showed moderate to marked improvement from baseline in overall assessment of inflammatory response. Forty-nine percent of placebo patients but only 17% of diclofenac patients were considered therapeutic failures (P < .001). By five to seven days, 82% of diclofenac sodium patients and 59% of placebo patients had corrected visual acuities of 20/40 or better (P < .001). There were no clinically important differences in mean intraocular pressure at any visit.

Transvenous "rescue" of a Kimray-Greenfield filter from the right atrium.

The complications of transvenous interruption of the inferior vena cava are most commonly associated with premature discharge of the device or inadvertent placement at a site other than the preselected position which is most commonly the infrarenal vena cava. This case report illustrates a useful technique for the transvenous retrieval of a partially ejected Kimray-Greenfield filter that became lodged in the right atrium. This simple technique may save the need for open thoracotomy to retrieve the misplaced filter.

Sexually transmittable diseases and other genital infections during adolescence.

PIP: Sexually transmitted (STD), diseases in which sexual contact is epidemiologically important but not the only mode of acquisition, will continueto increase in incidence unless effective control strategies can be applied. The recent increase in incidence has been due, in part, to increased levels of sexual activity among young people. Focus in this discussion is on the epidemiology of STD, the importance of an accurate sexual history in the diagnosis of STD, gonorrhea, syphilis, nongonococcal urethritis, vaginitis, herpes genitalis, pelvic inflammatory disease, and adolescent attitudes and knowledge. The sexual partners of infected patients are at particulary high risk of acquiring STD. The prevelence of inection among partners of patients with STD is so high that antibiotic therapy can be initiated as soon as a patient is identified as a sexual partner of an index case. Such epidemiolofgic treatment probably is appropriate in gonorrhea, syphilis, and infections produced by Haemophilus ducreyi, Gardnerella vaginalis, Calymmatobacterium granulomatis, Ureaplasma urealyticm, Chlamydia, trachomatis, and parasites. An important result of the sexual role of transmission is the high incidence of coinfection. The incidence of syphilis has remained relatively constant during the past 20 years, but gonorrhea has markedly increased in incidence, as have nonspecific urethritis in men, nonspecific genital infection in women, and herpes genitalis. The diagnosis of gonorrhea must be based on bacteriologic techniques; smears and cultures must be obtained from the urethra in the male and from the urethra and cervix in the female. The failure of prevention of gonorrhea has been due, in part, to a change in contraceptive methods, with greater use of oral contraceptives (OCs) and IUDs. The diagnosis of syphilis is established most accurately by examination of the exudate utilizing darkfield microscopy. The presence of nonspecific antibodies is most helpful as a diagnostic tool in the late primary phase of syphilitivc infection. Nongonococcal urethritis may be distinguished from gonococcal urethritis by the presence of a more mucoid, less copious, less purulent discharge. Nonspecific genital infection is a considerable problem in both sexes. Patients with nonspecific vaginitis experience itching and burning of the vulva, often accompanied by a slightly gray to white, frothy discharge that has an odor described as "fishy." Herpes genitalis is produced by herpes simplex virus type II and occasionally by herpes simplex virus type I. Clinical disease develops after an incubation period of 3-6 days. Approximately 500,000 cases of pelvic inflammatory disease occur annually in the US. An investigation designed to assess knowledge of, attitudes toward, and behavior regarding prophylaxis amoung a group of 200 single US female adolescents demonstrated much ignorance about veneral disease prophylaxis.^ieng

Therapeutic use of gentamicin in horses: concentrations in serum, urine, and synovial fluid and evaluation of renal function.

Serum, synovial fluid, and urine concentrations of gentamicin were measured in normal mature horses which had been given a single dose of the drug. Mean peak serum concentration (16.8 microgram/ml) occurred in horses 30 minutes after they were given a single intramuscular dose of 4.4 mg of gentamicin/kg of body weight. In horses given a smaller dose of gentamicin (1.7 mg/kg), mean peak serum concentrations of gentamicin (10.2 microgram/ml) appeared at 1 hour. Synovial fluid concentration was maximum at 2 hours for both doses; in horses given the larger dose, mean peak concentration was 6.4 microgram/ml, and in those given the smaller dose (1.7 mg/kg), 3.4 microgram/ml. Measurable concentrations of gentamicin in serum and synovial fluid persisted 8 hours. During the first 8 hours, percentages of gentamicin excreted in the urine were between 3.9 and 32.8% of the larger dose and between 3.3 and 13.4% of the smaller dose. Serum creatinine concentrations were serially measured in 10 hospitalized horses intramuscularly given 1.7 to 4.4 mg of gentamicin/kg 4 times a day' significant increase in creatinine concentration was not found.

Osteomyelitis: microbiologic, clinical, and therapeutic considerations.

A distinction between "acute" osteomyelitis and "chronic" osteomyelitis is difficult on both clinical and histopathologic grounds. The classification of osteomyelitis into three groups (hematogenous osteomyelitis, osteomyelitis secondary to a contiguous focus of infection, and osteomyelitis associated with vascular insufficiency) allows the physician to clearly distinguish among the types of infection on the bases of (1) the pathogenesis, (2) the bones involved, (3) the microorganisms responsible, and (4) the therapy. When antimicrobial agents are administered to a patient with any form of osteomyelitis, a bactericidal antibiotic should be employed, if possible. If feasible, a parenteral route of administration should be utilized, and therapy should be administered for a prolonged period of time. When more than one bactericidal antibiotic has been demonstrated to be effective against the isolated microorganisms, the least toxic agent should be selected.

Newer antibiotics: guidelines for use.

The number of antimicrobial agents available for use has increased significantly since the introduction of penicillin in the mid 1940s. Consequently, choosing among them has become an increasingly complex problem. In selecting an antibiotic, careful consideration must be given to the status of the patient and to the organism isolated. In addition, the physician must have detailed knowledge about the specific characteristics of each agent and must apply basic guidelines of antimicrobial therapy in order to make a rational choice.

[Surveillance of bacterial resistance in China (1998-1999)].

OBJECTIVE: To determine the rates of bacterial resistance of clinical isolates obtained from patients with hospital infections (HI) or community acquired infections (CAI) in the study wards of 13 hospitals located at different areas in China. METHODS: Susceptibility test was performed on 2 081 strains isolated from 13 hospitals, using standard plate dilution method according to the guidelines of NCCLS (1998). MIC(50) and MIC(90) were used to show the antibacterial activity of antimicrobial agents, and data of R%, I% and S% represent resistant, intermediate and susceptible rates of bacteria to antimicrobial agents tested. RESULTS: Among total 98 strains of S. aureus, 87 were isolated from patients with CAI and 11 were from HI patients. The incidence of methicillin resistant S.aureus (MRSA) from total infections caused by S. aureus was 27.55%, while the incidence of MRSA from HI patients was 81.82%, which was significantly higher than that (21.84%) from CAI patients. The rate of penicillin resistant S. pneumoniae (PRSP) (R% + I%) was 22.50%; the rate of R (MIC >/= 2 mg/L) was 2.5%, and most of PRSP strains was intermediate, with I% of 20%. No strains of S. aureus, neither strains of E. faecalis, nor of E. faecium were found resistant to vancomycin. The intermediate rate (I%) of E. faecalis and E. faecium to vancomycin was 3.23% and 3.77%, respectively. Cross resistance of E. coli to quinolones was present obviously, and more than 60% of E. coli strains were resistant to fluoroquinolones tested. CONCLUSION: Multi-drug resistance (MDR) of bacteria is a serious problem in China, including MDR of MRSA, PRSP, and enterobacteriaceae; and the resistant rate of enterobacterinceae is the highest up-to-date.

Quantum mechanics. Mechanically detecting and avoiding the quantum fluctuations of a microwave field.

Quantum fluctuations of the light field used for continuous position detection produce stochastic back-action forces and ultimately limit the sensitivity. To overcome this limit, the back-action forces can be avoided by giving up complete knowledge of the motion, and these types of measurements are called "back-action evading" or "quantum nondemolition" detection. We present continuous two-tone back-action evading measurements with a superconducting electromechanical device, realizing three long-standing goals: detection of back-action forces due to the quantum noise of a microwave field, reduction of this quantum back-action noise by 8.5 ± 0.4 decibels (dB), and measurement imprecision of a single quadrature of motion 2.4 ± 0.7 dB below the mechanical zero-point fluctuations. Measurements of this type will find utility in ultrasensitive measurements of weak forces and nonclassical states of motion.