Continuous phase shift of sinusoidal signals using injection locked oscillators

This work presents an alternative to generate continuous phase shift of sinusoidal signals based on the use of super harmonic injection locked oscillators (ILO). The proposed circuit is a second harmonic ILO with varactor diodes as tuning elements. In the locking state, by changing the varactor bias, a phase shift instead of a frequency shift is observed at the oscillator output. By combining two of these circuits, relative phases up to 90 could be achieved. Two prototypes of the circuit have been implemented and tested, a hybrid version working in the range of 200-300 MHz and a multichip module (MCM) version covering the 900¿1000 MHz band.

Anaerobically controlled expression system derived from the arcDABC operon of Pseudomonas aeruginosa: application to lipase production.

The anaerobically inducible arcDABC operon encodes the enzymes of the arginine deiminase pathway in Pseudomonas aeruginosa. Upon induction, the arcAB mRNAs and proteins reach high intracellular levels, because of a strong anaerobically controlled promoter and mRNA processing in arcD, leading to stable downstream transcripts. We explored the usefulness of this system for the construction of expression vectors. The lacZ gene of Escherichia coli was expressed to the highest levels when fused close to the arc promoter. Insertion of lacZ further downstream into arcA or arcB did not stabilize the intrinsically unstable lacZ mRNA. On the contrary, lacZ mRNA appeared to be a vulnerable endonuclease target destabilizing arcAB mRNAs in the 5'-to-3' direction in P. aeruginosa. The native arc promoter was modified for optional expression in the -10 sequence and in the -40 region, which is a binding site for the anaerobic regulator ANR. In P. aeruginosa grown either anaerobically or with oxygen limitation in unshaken cultures, this promoter was stronger than the induced tac promoter. The P. aeruginosa lipAH genes, which encode extracellular lipase and lipase foldase, respectively, were fused directly to the modified arc promoter in an IncQ vector plasmid. Semianaerobic static cultures of P. aeruginosa PAO1 carrying this recombinant plasmid overproduced extracellular lipase 30-fold during stationary phase compared with the production by strain PAO1 without the plasmid. Severe oxygen limitation, in contrast, resulted in poor lipase productivity despite effective induction of the ANR-dependent promoter, suggesting that secretion of active lipase is blocked by the absence of oxygen. In conclusion, the modified arc promoter is useful for driving the expression of cloned genes in P. aeruginosa during oxygen-limited growth and stationary phase.

15N uptake fom manure and fertilizer sources by three consecutive crops under controlled conditions

There are several regions of the world where soil N analysis and/or N budgets are not used to determine how much N to apply, resulting in higher than needed N inputs, especially when manure is used. One such region is the North Central "La Comarca Lagunera", one of the most important dairy production areas of Mexico. We conducted a unique controlled greenhouse study using 15N fertilizer and 15N isotopic-labeled manure that was labeled under local conditions to monitor N cycling and recovery under higher N inputs. The manure-N treatment was applied only once and was incorporated in the soil before planting the first forage crop at an equivalent rate of 30, 60 and 120 Mg ha-1 dry manure. The 15N treatments were equivalent to 120 and 240 kg ha-1 (NH4)2SO4-N for each crop. The total N fertilizer for each N fertilized treatment were 360, and 720 kg ha-1 N. We found very low N recoveries: about 9 % from the manure N inputs, lower than the 22 to 25 % from the fertilizer N inputs. The manure N recovered belowground in soil and roots ranged from 82 to 88 %. The low recoveries of N by the aboveground and low soil inorganic nitrate (NO3-N) and ammonium (NH4-N) content after the third harvested suggested that most of the 15N recovered belowground was in the soil organic form. The losses from manure N inputs ranged from 3 to 11 %, lower than the 34 to 39 % lost from fertilizer N sources. Our study shows that excessive applications of manure or fertilizer N that are traditionally used in this region will not increase the rate of N uptake by aboveground compartment but will increase the potential for N losses to the environment.

Efficacy of brief motivational intervention in reducing binge drinking in young men: A randomized controlled trial.

Background: Brief motivational intervention (BMI) is one of the few effective strategies targeting alcohol consumption, but has not been tested in young men in the community. We evaluated the efficacy of BMI in reducing alcohol use and related problems among binge drinkers and in maintaining low-risk drinking among non-bingers. Methods: A random sample of a census of men included during army conscription (which is mandatory for 20-year-old males in Switzerland) was randomized to receive a single face-to-face BMI session (N = 199) or no intervention (N = 219). A six-month follow-up rate was obtained for 88.7% of the subjects. Results: Among binge drinkers, there was 20% less drinking in the BMI group versus the control group (incidence rate ratio = 0.80, confidence interval 0.66-0.98, p = 0.03): the BMI group showed a weekly reduction of 1.5 drinks compared to an increase of 0.8 drinks weekly in the control group. Among subjects who experienced one or more alcohol-related consequences over the last 12 months, there was 19% less drinking in the BMI group compared to the control group (incidence rate ratio = 0.81; confidence interval 0.67-0.97, p = 0.04). Among non-bingers, BMI did not contribute to the maintenance of low-risk drinking. Conclusion: BMI reduced the alcohol use of binge drinkers, particularly among those who experienced certain alcohol-related adverse consequences. No preventive effect of BMI was observed among non-bingers. BMI is a plausible secondary preventive option for young binge drinkers. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

Combined efficacy of acamprosate and disulfiram in the treatment of alcoholism: a controlled study.

This study presents the results of a multicenter investigation of the efficacy of acamprosate in the treatment of patients with chronic or episodic alcohol dependence. One hundred eighteen patients were randomly assigned to either placebo or acamprosate, and both groups were stratified for concomitant voluntary use of disulfiram. Treatment lasted for 360 days, with an additional 360-day follow-up period. The primary efficacy parameters evaluated were: relapse rate and cumulative abstinence duration (CAD). Results were analyzed according to Intention-To-Treat principles using chi2, t, and multiple regression analyses where appropriate. After 30 days on study medication, 40 of 55 (73%) acamprosate-treated patients were abstinent, compared with 26 of 55 (43%) placebo-treated patients (p = 0.019). The treatment advantage remained throughout the study medication period and was statistically significant until day 270 (p = 0.028). Twenty-seven percent of patients on acamprosate and 53% of patients on placebo had a first drink within the first 30 days of the study. The mean CAD was 137 days (40% abstinent days) for the patients treated with acamprosate and 75 days (21% abstinent days) for the placebo group (p = 0.013). No adverse interaction between acamprosate and disulfiram occurred, and the subgroup who received both medications had a better outcome on CAD than the those on only one or no medication. Acamprosate was well tolerated. Diarrhea was the only significant treatment-induced effect. It was concluded that acamprosate was a useful and safe pharmacotherapy in the long-term treatment of alcoholism. Concomitant administration of disulfiram improved the effectiveness of acamprosate.

HIV-1 superinfection with a triple-class drug-resistant strain in a patient successfully controlled with antiretroviral treatment.

We report a case of HIV-1 superinfection (HSI) with a clade B, triple-class resistant virus in a patient successfully controlling viremia with continuous combination antiretroviral therapy started 8 years earlier during primary HIV infection. The course of HIV infection prior to HSI was monitored in both the source partner and recipient (8 and 11 years, respectively) and 4 years following HSI. This case report demonstrates re-infection with HIV-1 despite effective combination antiretroviral therapy.

Cefuroxime prophylaxis is effective in noninstrumented spine surgery: a double-blind, placebo-controlled study.

STUDY DESIGN: Double-blind, placebo-controlled randomized clinical trial. OBJECTIVE: To assess the efficacy of 1 preoperative 1.5 g dose of cefuroxime in preventing surgical site infection after surgery for herniated disc. SUMMARY OF BACKGROUND DATA: Antibiotic prophylaxis was only tested in nonconclusive trials in this setting. METHODS: The study was conducted in 2 university hospitals in Switzerland. Patients were assessed for occurrence of surgical site infection (defined by the criteria of the Centers for Diseases Control and Prevention), other infections, or adverse events up to 6 months after surgery. Outcome measures were compared in a univariate, per-protocol analysis. RESULTS: Baseline characteristics were similar in patients allocated to cefuroxime (n = 613) or placebo (n = 624). Eight (1.3%) patients in the cefuroxime group and 18 patients (2.8%) in the placebo group developed a surgical site infection (P = 0.073). A diagnosis of spondylodiscitis or epidural abscess was made in 9 patients in the placebo group, but none in the cefuroxime group (P < 0.01), which corresponded to a number necessary to treat of 69 patients to prevent one of these infections. There were no significant adverse events attributed to either cefuroxime or placebo. CONCLUSION: A single, preoperative dose of cefuroxime significantly reduces the risk of organ-space infection, most notably spondylodiscitis, after surgery for herniated disc.

Risk of mental disorders in children of parents with alcohol or heroin dependence: a controlled high-risk study.

Aim: To assess the specific effect of alcohol dependence (AD) or heroin dependence (HD) in patients and their spouses on the risk of psychopathology in their 276 6.0- to 17.9- year-old children (mean 11.3 years). Methods: The sample included 101 offspring of patients with AD, 23 of patients with HD, and 152 of medical controls, as well as their 2 parents. Participants were assessed using semistructured diagnostic interviews and family history reports by psychologists blind to patient diagnoses. Results: Children of HD and AD patients had largely elevated rates of recurrent major depressive disorder. Children of HD patients were also at an increased risk for attention deficit hyperactivity disorder and substance use disorders (SUD). There were interactions between SUD in the 2 parents to increase the risk of SUD in offspring. Conclusions: These results emphasize the need for prompt identification and treatment of these children and highlight the need to pay clinical attention not only to the patient, but also to the co-parent in order to optimize prevention in offspring.

The effectiveness of a standardised preoperative preparation in reducing child and parent anxiety: a single-blind randomised controlled trial.

AIMS: To evaluate the effect of a structured preoperative preparation on child and parent state anxiety, child behavioural change and parent satisfaction. BACKGROUND: It is estimated that around 50-70% of hospitalised children experience severe anxiety and distress prior to surgery. Children who are highly anxious and distressed preoperatively are likely to be distressed on awakening and have negative postoperative behaviour. Although education before surgery has been found to be useful mostly in North America, the effectiveness of preoperative preparation programme adapted to the Australian context remains to be tested. DESIGN: This single-blind randomised controlled study was conducted at a tertiary referral hospital for children in Western Australia. METHODS: Following ethics approval and parental consent, 73 children and one of their carers (usually a parent) were randomly assigned into two groups. The control group had standard practice with no specific preoperative education and the experimental group received a preoperative preparation, including a photo file, demonstration of equipment using a role-modelling approach and a tour. RESULTS: The preoperative preparation reduced parent state anxiety significantly (-2·32, CI -4·06 to -0·56, p = 0·009), but not child anxiety (-0·59, CI -1·23 to 0·06, p = 0·07). There was no significant difference in child postoperative behaviour or parent satisfaction between the groups. There was a significant two-point pain score reduction in the preoperative preparation group, when compared with the control group median 2 (IQR 5) and 4 (IQR 4), respectively (p = 0·001).¦CONCLUSIONS: Preoperative preparation was more efficient on parent than child. Although the preoperative preparation had limited effect on child anxiety, it permitted to decrease pain experience in the postoperative period.¦RELEVANCE TO CLINICAL PRACTICE: Parents should be actively involved in their child preoperative preparation.

Computer-assisted cartography using topographic properties: precision and accuracy of local soil maps in central Mexico

Map units directly related to properties of soil-landscape are generated by local soil classes. Therefore to take into consideration the knowledge of farmers is essential to automate the procedure. The aim of this study was to map local soil classes by computer-assisted cartography (CAC), using several combinations of topographic properties produced by GIS (digital elevation model, aspect, slope, and profile curvature). A decision tree was used to find the number of topographic properties required for digital cartography of the local soil classes. The maps produced were evaluated based on the attributes of map quality defined as precision and accuracy of the CAC-based maps. The evaluation was carried out in Central Mexico using three maps of local soil classes with contrasting landscape and climatic conditions (desert, temperate, and tropical). In the three areas the precision (56 %) of the CAC maps based on elevation as topographical feature was higher than when based on slope, aspect and profile curvature. The accuracy of the maps (boundary locations) was however low (33 %), in other words, further research is required to improve this indicator.

Controlled expression of recombinant proteins in Physcomitrella patens by a conditional heat-shock promoter: a tool for plant research and biotechnology.

The ability to express tightly controlled amounts of endogenous and recombinant proteins in plant cells is an essential tool for research and biotechnology. Here, the inducibility of the soybean heat-shock Gmhsp17.3B promoter was addressed in the moss Physcomitrella patens, using beta-glucuronidase (GUS) and an F-actin marker (GFP-talin) as reporter proteins. In stably transformed moss lines, Gmhsp17.3B-driven GUS expression was extremely low at 25 degrees C. In contrast, a short non-damaging heat-treatment at 38 degrees C rapidly induced reporter expression over three orders of magnitude, enabling GUS accumulation and the labelling of F-actin cytoskeleton in all cell types and tissues. Induction levels were tightly proportional to the temperature and duration of the heat treatment, allowing fine-tuning of protein expression. Repeated heating/cooling cycles led to the massive GUS accumulation, up to 2.3% of the total soluble proteins. The anti-inflammatory drug acetyl salicylic acid (ASA) and the membrane-fluidiser benzyl alcohol (BA) also induced GUS expression at 25 degrees C, allowing the production of recombinant proteins without heat-treatment. The Gmhsp17.3B promoter thus provides a reliable versatile conditional promoter for the controlled expression of recombinant proteins in the moss P. patens.