One-cm-thick Si detector at LHe temperature

A silicon p-i-n diode of thickness 1 cm has been studied experimentally at liquid helium temperature. This preliminary study is aimed at the construction of a much bigger detector to detect low energy neutrino events.     

Ceftazidime plus amikacin plus teicoplanin or vancomycin in the empirical antibiotic therapy in febrile neutropenic cancer patients

A prospective randomized trial was performed to compare teicoplanin to vancomycin as part of the empirical antibiotic therapy of febrile neutropenic cancer patients. Fifty-three patients were randomized to receive ceftazidime (100 mg/kg daily every 8 h), amikacin (15 mg/kg daily every 8 h) and teicoplanin (6 mg/kg once a day) and 53 other patients received ceftazidime, amikacin (same dosages) and vancomycin (30 mg/kg/day every 6 h). In 99 evaluable episodes, the success rates were 54% for patients receiving teicoplanin and 52% for patients receiving vancomycin (p=0.76, 95% CI-18-23). The response rates were similar for patients with unexplained fever and for patients with documented infections. There were no differences in renal toxicity or cutaneous side effects between the two groups. The overall death rate was 18.9%, with 10 deaths in each group. The most important factor associated with death was the diagnosis of a fungal infection (p=0.001). Teicoplanin seems to be well tolerated and as effective as vancomycin in the empirical antibiotic therapy of fever in neutropenic cancer patients.     

Differential proprioceptive feedback and DRL performance of normal and septal rats.

In a study with 18 Long-Evans hooded rats, normal Ss and Ss with septal lesions were run on a differential reinforcement of low rate schedule in the presence or absence of a differential response feedback produced by systematically varying the force required to depress the lever. For each of 3 treatment conditions, the required force either decreased, increased, or remained constant. By the end of training, normal and lesioned Ss were not significantly different from each other on all performance measures examined when differential response feedback was provided (i.e., decreasing or increasing force). However, significant lesion-normal differences were present when such feedback was absent (i.e., constant force). (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cued DRL training: Effects on the permanence of lesion-induced overresponding.

Attempted to determine the degree to which lesions in the septum and anatomically related structures result in the presence and/or permanence of overresponding on a DRL 20-sec schedule. Male Long-Evans hooded rats were given 15 days of training to determine the presence or absence of overresponding. Ss that overresponded were divided into 2 groups, with one receiving 15 days of cued DRL training and the other receiving 15 days of regular DRL training. Overresponding occurred in 60 Ss following lesions in septum, hippocampus, medialis dorsalis, and ventral thalamus pars dorsalis. While in effect, cued DRL facilitated performance in 8 controls and in operated Ss but did not facilitate performance when removed in septals. Exposure to the cued DRL allowed hippocampals to reduce responding and increase the frequency of obtained reinforcements. Lesions in medialis dorsalis and ventral thalamus led to an overresponding that disappeared with prolonged regular DRL training. Cued DRL training actually functioned as a time-out from DRL training. Variations in the permanence of the overresponding symptom according to lesion locus preclude identification of the lesion-induced dysfunction based solely on the presence or absence of overresponding. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of prefeeding on the DRL performance of rats with septal lesions.

Conducted 2 experiments with a total of 17 Long-Evans male hooded rats (8 with septal lesions and 9 unoperated controls) to study the effects of prefeeding prior to daily sessions on a DRL-20 schedule. Prefeeding reduced responses and increased reinforcement in the case of septal Ss, regardless of the level of body weight. In the case of normal Ss, prefeeding led to a decrease in responding and an increase in the number of reinforcements obtained only when the Ss were at 85% of ad lib body weight. At ad lib levels, prefeeding, although it decreased responding, also decreased the frequency of obtained reinforcements. Results suggest an impairment in normal Ss in the discrimination of response feedback by stimulation arising from stomach distention. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A laser system for the parametric amplification of electromagnetic fields in a microwave cavity

We describe recent improvements in the development of the high power laser system used in the motion induced radiation (MIR) experiment to amplify electromagnetic fields inside a microwave cavity. The improvements made on the oscillator stabilization, the pulse train shaping device, and the spatial beam uniformity are reported.     

Studies on the catalytic dechlorination and abatement of chlorided VOC: the cases of 2-chloropropane, 1,2-dichloropropane and trichloroethylene

The conversion of monochloropropanes and dichloropropanes over acid catalysts has been investigated in the presence of oxygen. In the temperature range of 450–550 K, dehydrochlorination of monochloropropanes to propene and HCl occurs selectively over silica–alumina, while significant formation of chlorinated by-products is observed over ZSM5 zeolite catalyst even at higher temperatures. Dichloropropanes conversion over silica–alumina catalyst gives rise mainly to chloropropenes in the temperature range 500–700 K. CO_x are predominant products only at the highest reaction temperatures (just above 700 K). Water vapor in the feed only slightly affects conversions and selectivities. Deactivation processes occur upon dichloropropane conversion, mainly due to coke deposition.

The conversion of highly chlorinated compounds, such as trichloroethylene (TCE) has been tested over silica–alumina and over HY zeolite in the presence of water vapor in the so-called “steam reforming” conditions (HVOC:water=1:2). With diluted feed (1200 ppm) on HY, reaction occurs above 800 K and formation of chlorinated by-products is minimized, CO_x being the main reaction products. At higher HVOC concentrations conversion is obtained at even lower temperature (600 K), but no more negligible by-products formation has been detected. In our conditions zeolite catalyst is more effective in TCE total conversion than silica–alumina.