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Background Radionuclide ventriculography (RNVG) can be used to quantify mechanical dyssynchrony and may be a valuable adjunct in the assessment of heart failure with reduced ejection fraction (HFrEF). The study aims to investigate the effect of beta-blockers on mechanical dyssynchrony using novel RNVG phase parameters. Methods A retrospective study was carried out in a group of 98 patients with HFrEF. LVEF and dyssynchrony were assessed pre and post beta-blockade. Dyssynchrony was assessed using synchrony, entropy, phase standard deviation, approximate entropy, and sample entropy from planar RNVG phase images. Subgroups split by ischemic etiology were also investigated. Results An improvement in dyssynchrony and LVEF was measured six months post beta-blockade for both ischemic and non-ischemic groups. Conclusions A significant improvement in dyssynchrony and LVEF was measured post beta-blockade using novel measures of dyssynchrony.

Radionuclide ventriculography (RNVG) can be used to quantify mechanical dyssynchrony and may be a valuable adjunct in the assessment of heart failure with reduced ejection fraction (HFrEF). The study aims to investigate the effect of beta-blockers on mechanical dyssynchrony using novel RNVG phase parameters.A retrospective study was carried out in a group of 98 patients with HFrEF. LVEF and dyssynchrony were assessed pre and post beta-blockade. Dyssynchrony was assessed using synchrony, entropy, phase standard deviation, approximate entropy, and sample entropy from planar RNVG phase images. Subgroups split by ischemic etiology were also investigated.An improvement in dyssynchrony and LVEF was measured six months post beta-blockade for both ischemic and non-ischemic groups.A significant improvement in dyssynchrony and LVEF was measured post beta-blockade using novel measures of dyssynchrony.

Optical feedback cavity-enhanced absorption spectroscopy (OF CEAS) has been demonstrated with a thermoelectrically cooled continuous wave distributed feedback quantum cascade laser (QCL) operating at wavelengths around 7.84 μm. The QCL is coupled to an optical cavity which creates an absorption pathlength greater than 1000 m. The experimental design allows optical feedback of infra-red light, resonant within the cavity, to the QCL, which initiates self-locking at each TEM00 cavity mode frequency excited. The QCL linewidth is narrowed to below the mode linewidth, greatly increasing the efficiency of injection of light into the cavity. At the frequency of each longitudinal cavity mode, the absorption coefficient of an intracavity sample is obtained from the transmission at the mode maximum, measured with a thermoelectrically cooled detector: spectral line profiles of CH4 and N2O in ambient air were recorded simultaneously and with a resolution of 0.01386 cm−1. A minimum detectable absorption coefficient of 5.5×10−8 cm−1 was demonstrated after an averaging time of 1 s for this completely thermoelectrically cooled system. The bandwidth-normalised limit for a single cavity mode is 5.6×10−9 cm−1 Hz−1/2 (1σ).

Little is known about the effect of commercial rockweed (Ascophyllum nodosum) harvest on intertidal community structure, and on interactions among species. Using predator-exclusion cages and by simulating rockweed harvest, we studied the combined effects of predation by common eiders (Somateria mollissima) and harvest on an intertidal invertebrate community associated with rockweed. Predation had no effect on invertebrate species richness, and only a short-term (

A successful rabbit control operation was conducted in July 1992 on Blackstone Hill, Otago, New Zealand. A greater than 90% kill of rabbits was achieved using aerially sown sodium monofluoroacetate (1080) carrot bait. Streams and rivers on Blackstone Hill were monitored for 4 weeks after the operation and only two out of 29 samples contained measurable amounts of 1080 at 0.0003 and 0.0006 mg/1. Measurable amounts of 1080 occurred only within 48 h of the application of toxic bait. All subsequent samples were either free from 1080 or contained concentrations below the limit of detection (0.0003 mg/1). These levels pose no threat to humans, stock, or aquatic life.

Optical feedback cavity-enhanced absorption spectroscopy (OF-CEAS) has been demonstrated by coupling a distributed feedback diode laser to a ring cavity. Frequency-selected light decaying from the ring cavity is retro-reflected, inducing a counter-propagating intra-cavity beam, and providing optical feedback to the laser. At specific laser-to-cavity distances, all cavity mode frequencies return to the diode laser with the same phase, allowing spectra to be accumulated across the range of frequencies of the current-tuned laser. OF-CEAS has been used to measure very weak oxygen isotopologue ( 16O 18O and 16O 17O) absorptions in ambient air at wavelengths near 762 nm using the electric-dipole forbidden O 2 A-band. A bandwidth reduced minimum detectable absorption coefficient of 2.2 × 10 -9 cm -1 Hz -1/2 is demonstrated. © Springer-Verlag 2009.

Diode laser cavity ring-down spectroscopy is a versatile method for quantitative determination of trace atmospheric constituents. Examples include measurement of mixing ratios of small organic compounds, isotopologue-specific spectroscopy, and optical extinction by atmospheric aerosol particles.

In a recent experiment [1] a high efficiency regime of stable electron acceleration to kinetic energies ranging from 10 to 40 MeV has been achieved. The main parameters of the electron bunches are comparable with those of bunches provided by commercial Radio‐Frequency based Linacs currently used in Hospitals for Intra‐Operative Radiation Therapy (IORT). IORT is an emerging technique applied in operating theaters during the surgical treatment of tumors. Performances and structure of a potential laser‐driven Hospital accelerator are compared in detail with the ones of several commercial devices. A number of possible advantages of the laser based technique are also discussed.

While criteria for serodiagnosis of Chlamydia pneumoniae infection are well established, isolation of the organism is often difficult. To increase detection of this organism, C. pneumoniae-specific sequences were identified to permit amplification of C. pneumoniae by polymerase chain reaction (PCR). A cloned C. pneumoniae 474-bp PstI fragment was shown by dot blot and Southern hybridization to differentiate C. pneumoniae from the other Chlamydia spp., react with all C. pneumoniae isolates tested, and not recognize DNA from normal throat flora or common respiratory tract agents. This cloned fragment was sequenced and primers for use in PCR were chosen on the bases of GenBank analysis, G + C ratio, and absence of secondary structure. All C. pneumoniae isolates tested were amplified by the HL-1-HR-1 primer pair or the HM-1-HR-1 primer pair, producing the expected 437- and 229-bp amplification products, respectively. None of the Chlamydia trachomatis serovars (B/TW-5/OT, C/TW-3/OT, D/UW-3/Cx, E/UW-5/Cx, F/UW-6/Cx, H/UW-4/Cx, I/UW-12/Ur, and L2/434/Bu), Chlamydia psittaci strains (Mn, 6BC, GPIC, FP, and OA), HeLa cells, or other organisms tested were amplified. Reaction conditions including MgCl2, oligonucleotides, and primer concentrations and temperature were optimized before application to clinical samples. Clinical specimens from patients from whom C. pneumoniae was isolated were also positive by PCR, while samples from patients with known C. trachomatis or C. psittaci infection were not amplified by PCR.

Diabetes is frequently encountered in patients presenting with end-stage heart failure to be listed for transplantation. While diabetes used to be a contra-indication for heart transplantation, careful preoperative evaluation and individualized postoperative medication lead to long-term outcome after heart transplantation equal to non-diabetic patients. About 1/3 of transplanted patients develop a post-transplant diabetes. Several risk factors have been identified leading to this condition. Mostly, post-transplant diabetes is of temporary nature. Several studies have shown no impact of diabetes on the incidence of rejection, malignancies, and transplant vasculopathy. However, glucose intolerance must be taken into consideration when planing immunosuppressive therapy since different medications have distinct impact on glucose metabolism after transplant. A multidisciplinary team allows for closely monitoring and treating patients with diabetes after heart transplant.

The Jefferson Lab Hall A experiment E99-114 comprised a series of measurements to explore proton Compton scattering at high momentum transfer. For the first time, the polarisation transfer observables in the p (~ 0 ~ p) reaction were measured in the GeV energy range, where it is believed that quark-gluon degrees of freedom begin to dominate. The experiment utilised a circularly polarised photon beam incident on a liquid hydrogen target, with the scattered photon and recoil proton detected in a lead-glass calorimeter and a magnetic spectrometer, respectively.

Etude sur les fongicides maneb, mancozeb et zineb qui sont respectivement les complexes de Mn, Mn−Zn et Zn. Zineb donne de faibles pics endothermiques a 166, 252 et 293°C. Maneb et mancozeb ont un pic endothermique e intense a 185-190°C (degagement de CS 2 ) et un pic plus faible a 290°C (degagement de H 2 S)

A new medium (XT80) containing trimethoprim-sulfamethoxazole (TMP-SMZ) was characterized and compared with kanamycin-containing tryptic soy agar (KA) for the recovery of multiply resistant organisms (MRO) in rectal and stool cultures. Cultures from 151 patients hospitalized for bone marrow transplantation were screened for MRO. A total of 366 MRO were recovered from 702 cultures on 94 patients during a 6-month period. XT80 detected more gram-negative bacilli and Corynebacterium spp. than KA. Detection of Staphylococcus spp. was equivalent for the two media. Multiple-antibiotic resistance, defined as resistance to three or more classes of antibiotics, was confirmed by standard agar disk diffusion susceptibility testing. Growth on XT80 correctly identified heteroresistant strains of methicillin-resistant Staphylococcus spp. XT80 more rapidly detected thymidine-dependent mutants of Staphylococcus spp. and members of the family Enterobacteriaceae. Lipophilic Corynebacterium spp., including Corynebacterium group JK, also were more readily detected with XT80. TMP-SMZ given as prophylaxis against Pneumocystis carinii infection exerts a selective pressure on organisms that colonize immunocompromised patients and appears to select for colonization with MRO. Colonization with MRO preceded infection for 94% of 36 patients who developed bacteremia. XT80 is a useful screening tool; growth on this medium correlates closely with resistance to TMP-SMZ and is as accurate a predictor as KA for the carriage of MRO.

The effect of delay in processing on results of lysis-centrifugation (LC; Isolator) blood cultures was assessed in 4,577 paired blood specimens. Blood specimens were obtained at all hours from 384 febrile marrow transplant patients with indwelling venous catheters and were processed by the LC technique and by a conventional two-bottle method. Most patients (84%) were receiving broad-spectrum antibiotics at the time of blood culture. Specimens were delivered to the laboratory, where Isolator tubes were held at 35 degrees C and processed in batches between 0700 and 1730 h daily. This procedure resulted in a delay beyond the manufacturer-suggested processing time of less than 8 h for 1,853 (42%) of the LC cultures. There was no overall difference in the recovery of organisms present in LC cultures processed after being held for 8 to 24 h compared with the conventional two-bottle method. LC methodology had shorter time to detection than the conventional method for detection of Candida spp. and Pseudomonas spp. (P less than 0.05). However, time to detection for Streptococcus spp. and members of the family Enterobacteriaceae, responsible for 16.3% of total isolates, was prolonged significantly by delay in processing when compared with the conventional two-bottle method (P less than 0.01). Results of this study support the recommendation of the manufacturer for processing of Isolator tubes within 8 h or less. Although one can safely delay processing beyond 8 h in terms of total recovery of organisms, such delays were associated with longer time to detection for certain important potentially pathogenic organisms which accounted for a sizeable proportion of blood culture isolates from marrow transplant patients.

Methods.—The great difficulties heretofore encountered in investigating the course of nerve fibres in the brain have been, firstly, the want of a method of preparation by which their gross anatomy could be thoroughly exposed, and, secondly, the failure of any previously known process of staining to satisfactorily indicate their direction on microscopic examination. In endeavouring to collect reliable data from the records of lesions of the human brain, it becomes only too evident that until more efficient methods of localising lesions be adopted than those generally in use at the present day, little can possibly be added to the knowledge we already possess.

Measurements have been made of the sum of the cathode- and anode-fall voltages of arcs moving in a transverse magnetic field between copper and brass electrodes in air, argon and helium. The experiments have covered a range of arc current of 40-700 A and a velocity range up to 470 m s−1. The gas pressure was mainly about 1 atm but a check at 11 atm showed no major difference. Comparison between these voltages, the excitation and ionization potentials of the gases and recent data on cathode-fall voltages of static arcs show that even with arcs moving at speeds up to nearly 500 m s−1 on cold-cathode emitting materials, ionization of electrode vapour rather than gas appears to have occurred in the cathode-fall region. The ionized vapour is generally that of the cathode, but it is possible for anode material carried by vapour jets to be ionized in the cathode-fall region when the arc is moving sufficiently slowly.

Field tests with small cages were used to determine if a reduced concentration of carbaryl (Sevin® 4 Oil) in a flaky wheat bran bait and a reduced rate of application of the bait could still yield satisfactory control of Anabrus simplex Haldeman on rangeland. A reduction from 5% AI to 2% AI in concentration yielded no statistical difference in mortality. The tests indicate that control with bait may be achieved with 60% less carbaryl and a reduction in rate of application as great as 75% when compared with present carbaryl bait labels.

Cefixime was 8 to 10 times more active than cefaclor and augmentin against isolates of Escherichia coli, Klebsiella pneumoniae and Salmonella typhi, MIC90 values ranging from 0.06 to 0.25 micrograms/ml. However, none of these three drugs was particularly active against isolates of more resistant gram-negative bacilli such as Enterobacter, Serratia, Citrobacter, Acinetobacter, Providencia and Achromobacter spp. The lowest MIC values for gram-negative bacilli were seen with ciprofloxacin, except for isolates of Acinetobacter, where cotrimoxazole was the most active of the five drugs studied. Augmentin and ciprofloxacin exhibited the lowest MICs for isolates of streptococci and corynebacteria. Although cefixime may be among the most active oral beta-lactam drugs, it does not appear to be useful for treatment of infections caused by more resistant gram-negative bacilli.

Forty-two patients with elevated serum prolactin were treated in a randomized, open-label trial with the conventional ergot bromocriptine, or a new ergot pergolide. Before treatment, the patients underwent thorough endocrine evaluation and computed tomographic scan. All patients had prolactin levels greater than 25 ng/ml, and 27 patients had a pituitary mass. Follow-up studies performed after 6 months of treatment showed both drugs effectively reduced prolactin levels to normal, though pergolide effects were more rapid. There was no change in the contents of the pituitary fossa in the 10 patients with hyperprolactinemia but without pituitary mass. Sixty percent of patients with pituitary mass had diminution of tumor size. Pergolide appears to be an effective medical treatment for hyperprolactinemia and pituitary tumor and offers a possible alternative to bromocriptine and surgical treatment.

This report deals with a new integrated thermionic device capable of withstanding ambient temperatures in excess of 500/sup 0/C, which eliminates the problems associated with earlier versions. The history of the ITC (Integrated Thermionic Circuit) is traced along with Los Alamos Scientific Laboratory (LASL) interests for geothermal instrumentation. The evolution of the new structure is discussed and a set of practical device design and performance equations are demonstrated.

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A simple physical theory is developed which permits a calculation of the significant points of avalanche transistor transient behavior. A model for the transistor is defined in terms of charge variables and the physical parameters of the device. The transient performance of the model is calculated by focusing attention on the minority carrier charge stored in the base region and the influence of basewidth modulation upon this stored charge. In the charge formulation of the problem, the physical details of the avalanche multiplication process need not be considered; multiplication is accounted for by the boundary conditions which it imposes upon the stored charge. Good agreement has been obtained between calculated and experimentally observed data for a simple avalanche transistor relaxation oscillator.