Very low noise mixer at 115 GHz using a Mott diode cooled to 20 K

Measurements on a cooled resistive mixer are reported using a Mott-barrier diode cooled to 20 K, operating at 115 GHz and pumped with a local oscillator power as low as 150 ?W. The mixer noise temperature of 200 K is not only the lowest reported for a resistive mixer above 90 GHz but indicates that some improvement in shot-noise models for resistive mixers is desirable.     

Prognostic factors for recurrence of a first seizure during childhood

This study was designed with the objective of evaluating the chance of recurrence in our area and to answer questions regarding prognostic factors capable of helping in the management of the first seizure in childhood. One hundred and thirty six children from 1 month to 12 years of age seen at the Pediatric Emergency Division of Hospital de Clínicas de Porto Alegre because of a first seizure with or without triggering factors were included in the study. The follow-up included 121 children. We concluded that family history of seizures, presence of triggering factors at first event, seizure type, seizure duration and paroxysmal electroencephalographic abnormalities were predictive factors for seizure recurrence. The recurrence in this sample was 36.36% during the study. Cumulative recurrence risks were 14.88%, 23.14%, 28.93%, 33.06% and 35.54% to 3, 6, 9, 12 and 15 months, respectively.     

Lycoperdonosis

In a defined group of 10,281 generally healthy inpatients admitted to surgical services, two deaths were identified as being due in part to an adverse effect of a drug, for a rate of 0.19 drug-related dealths/1,000 surgical patients (approximate 95 per cent confidence limits, 0.02 to 0.71/1,000). Both deaths occurred in women more than sixty years old and were due to hemorrhage associated with heparin therapy.     

Effect of conductive thermal-control paint on spacecraft-antenna performance

The effect of applying a conductive thermal-control paint to the surface of a reflector antenna has been investigated at X band frequencies using a swept-frequency technique. With a particular space-qualified paint, a maximum boresight gain loss of 0.1 dB was recorded.     

Fast algorithm for the exact determination of the mapped effective areas of trihedral radar reflectors

A computer processing technique has recently been described for the evaluation of monostatic scattering cross-sections of regularly shaped trihedral radar reflectors, the final stage of which involves the determination of an effective area mapped out by orthogonal projections of real and image aperture boundary lines on an oblique plane. Previously the area determination was carried out by an integration process plus a geometrical procedure. An alternative method described here reduces the area to a set of triangles which are evaluated and summed: this gives an exact value and is approximately 50 times faster in computer CPU time.     

Self-esteem and sources of cognitive bias in the evaluation of past performance

Examined relationships between self-esteem and cognitive biases involved in processing self-relevant information. 49 male and 52 female paid college students completed a series of self-esteem measures, participated in an anagram-solving task, and then answered questions concerning (a) their standards for successful achievement and (b) their retention of solved and unsolved anagrams. Low self-esteem males had higher discrepancies between their criteria for successful achievement and perceived performances than high-self-esteem males; females did not show this relationship. Predicted relationships between self-esteem and retention of solved vs unsolved anagrams were not found for either males or females. As anticipated, no significant relationship was found between level of performance and self-esteem. Implications for interpreting the self-esteem construct and for identifying sex differences in self-esteem are discussed. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Thermally initiated oxidation and ignition of flexible polyurethane foams

Oxidation and ignition of flexible polyurethane foams have been investigated by observing the effects of internal and external heating. External temperatures of some 190°C are required to induce combustion. Internal temperatures of 250 ?350°C initiate a self-propagating internal reaction which results in foam ignition when the reaction reaches the foam surface. The stability of a polyurethane foam to such heating increases with the age of the foam.     

Craniofacial electromyogram activation response: another indicator of anesthetic depth

The female gametophyte is an absolutely essential structure for angiosperm reproduction. It produces the egg cell and central cell (which give rise to the embryo and endosperm, respectively) and mediates several reproductive processes including pollen tube guidance, fertilization, the induction of seed development, and perhaps also maternal control of embryo development. Although much has been learned about these processes at the cytological level, specific molecules mediating and controlling megagametogenesis and female gametophyte function have not been identified. A genetic approach to the identification of such molecules has been initiated in Arabidopsis and maize. Although genetic analyses are still in their infancy, mutations affecting female gametophyte function and specific steps of megagametogenesis have already been identified. Large-scale genetic screens aimed at identifying mutants affecting every step of megagametogenesis and female gametophyte function are in progress; the characterization of genes identified in these screens should go a long way toward defining the molecules that are required for female gametophyte development and function.     

Suppression of human bladder cancer growth by increased expression of C-CAM1 gene in an orthotopic model

Recently, we demonstrated that an immunoglobulin-like cell adhesion molecule, C-CAM, acts as a tumor suppressor in prostate cancer. It is known that C-CAM is expressed in many epithelial cell types. In this study, we tested the possibility that C-CAM may also suppress bladder cancer progression. We used an orthotopic tumor model, which provides a relevant organ condition for examining the interaction between primary tumor cells and their microenvironment; this interaction has a critical impact on the behavior of carcinoma. We constructed a recombinant adenovirus expressing C-CAM1 (an isoform of C-CAM) and infected the 253J B-V cell line, a tumorigenic human bladder carcinoma subline. In vitro, C-CAM1 protein was detected in C-CAM1 adenovirus-infected cells but not in antisense control virus-infected cells, and the levels of expression showed dose dependency. When these cells were injected orthotopically in nude mice, we found that the increased expression of C-CAM1 in the 253J B-V cells repressed the growth of 253J B-V-induced tumors. Taken together, these data indicate that C-CAM1 is a potent tumor suppressor in human bladder cancer.