InGaAs/InGaAsP MQW optical amplifier integrated withgrating-assisted vertical-coupler noise filter

A photonic integrated circuit with an InGaAs/InGaAsP multiple-quantum-well (MQW) traveling-wave optical amplifier and a grating-assisted vertical-coupler filter as a noise filter have been demonstrated. A fiber-to-amplifier/filter gain of ~0.5 dB and a 3-dB filter bandwidth (FWHM) of ~70 Å at 1.56 μm filter center wavelength have been achieved. This photonic circuit is potentially suitable as a building-block for preamplifier lightwave receivers or high-gain, high-power optical amplifiers which are essential for optical communication systems and lightwave networks     

Characterization of a slowly inactivating outward current in adult mouse ventricular myocytes

We recently have reported that suppression of the slowly inactivating component of the outward current, Islow, in ventricular myocytes of transgenic mice (long QT mice) overexpressing the N-terminal fragment and S1 segment of Kv1.1 resulted in a significant prolongation of action potential duration and the QT interval. Here we describe the detailed biophysical properties and physiological role of Islow by applying the whole-cell patch-clamp technique at both room temperature and 37 degreesC. This current activates rapidly with time constants ranging from 3.8+/-0.8 ms at -20 mV to 2.1+/-0.5 ms at 50 mV at room temperature. The half-activation voltage and slope factor are -12.5+/-2.6 mV and 7. 7+/-1.0 mV, respectively. The inactivation of this current is slow compared with the fast inactivating component Ito, with time constants of approximately 100 ms at 37 degreesC. The steady-state inactivation of Islow is not temperature-dependent, with half-inactivation voltages and slope factors of -35.1+/-1.3 and -5. 4+/-0.4 mV at 37 degreesC, and -37.6+/-1.8 and -5.8+/-0.6 mV at room temperature. Double exponentials were required to describe the time-dependent recovery of Islow from steady-state inactivation, with time constants of 233+/-34 and 3730+/-702 ms at 37 degreesC, and 830+/-240 and 8680+/-2410 ms at room temperature. Islow is highly sensitive to 4-aminopyridine but is insensitive to tetraethylammonium, alpha-dendrotoxin, and E-4031. Stimulation with action-potential waveforms under voltage-clamp mode revealed that this current plays an important role in the early and middle phases of repolarization of the cardiac action potential. We conclude that the biophysical properties and pharmacological profiles of Islow are similar to those of Kv1.5-encoded currents.     

Lymph node revealing solution: a new method for detection of minute axillary lymph nodes in breast cancer specimens

The staging and prognosis of patients with breast cancer is related to the presence or absence of axillary lymph node involvement. However, in some cases no lymph nodes or too small a number of lymph nodes are revealed by the traditional method of palpating and sectioning the axillary fat. In the present study we demonstrate the usefulness of the lymph node revealing solution (LNRS) in breast cancer. Specimens from 13 patients, in whom <10 lymph nodes were identified in the axilla by the traditional method, were included in the study. After excising the lymph nodes by the traditional method, axillary tissue was immersed in LNRS for 6-12 hours. Additional lymph nodes, which stood out as white chalky nodules, were excised and processed as usual. The LNRS increased the mean number of nodes per case from 6.0+/-2.5 found by the traditional method to 12.54+/-4.61 nodes per case (p < 0.01). The size of the nodes identified by the LNRS was significantly smaller (p < 0.01) than those detected by the traditional method. The LNRS changed the lymph node stage of the disease in four of the studied cases (30%). LNRS seems to be the technique of choice for detection of axillary lymph nodes in cases where the number of detected lymph nodes by the traditional method is too small for accurate staging.     

Are there sex differences in neuropsychological functions among patients with schizophrenia?

OBJECTIVE: Studies of sex differences in neuropsychological performance in schizophrenia report inconsistent results, due in part to methodological artifacts. The study presented here was specifically designed to examine sex differences in neuropsychological performance. It was hypothesized that schizophrenic women would exhibit fewer neuropsychological deficits than schizophrenic men and that their performance would be more similar to that of normal women than schizophrenic men's performance would be to that of normal men. METHOD: Thirty-one outpatients with DSM-III-R-defined schizophrenia were systematically sampled from an extensive service network serving a large urban catchment area for seriously mentally ill persons. Twenty-seven normal comparison subjects were matched within sex on the basis of age, parental socioeconomic status, ethnicity, and handedness. An extensive neuropsychological test battery was administered, and multivariate analysis of variance was used to test for the effects of sex and group and sex-by-group interactions. RESULTS: Male patients were significantly impaired across all functions in comparison with normal male subjects and on tests of attention, verbal memory, and executive functions in comparison with female patients. Female patients performed significantly worse than female normal comparison subjects only on tests of attention, executive functions, visual memory, and motor functions. CONCLUSIONS: The findings suggest that women with schizophrenia may be less vulnerable to particular cognitive deficits, especially those involving verbal processing, than schizophrenic men.     

The role of an academic institute in setting national environmental policy: The case of Israel

Two major players are active in determining the development of environmental policies: the government and “the public.” These diverse players have intrinsic limitations and are often driven by different agenda, different aims, and different means. Therefore, inconsistent actions and lack of a clear agenda and action plan characterize the environmental policy. There is an essential role for a third player, namely, a team that is as professional and as objective as possible. The Samuel Neaman Institute (SNI) has taken it upon itself to serve as this third party, and has been providing the scientific background needed to develop and propose a rational and environmental set of priorities for Israel since 1998.     

Anaphylactoid reactions in children receiving high-dose intravenous cyclosporine for reversal of tumor resistance: the causative role of improper dissolution of Cremophor EL

PURPOSE: An unusually high incidence of anaphylactoid reactions was observed during a phase I/II trial of high-dose intravenous cyclosporine (CsA) therapy to attenuate tumor multidrug resistance (MDR). Five of 21 children experienced severe anaphylactoid reactions shortly after initiation of the first or second CsA infusion. We hypothesized that improper dissolution of the vehicle Cremophor EL may have been a cause for these anaphylactoid reactions. METHODS: All nurses who had administered intravenous CsA were interviewed regarding their technique of preparing the infusion and the occurrence of an anaphylactoid reaction. The responses were statistically analyzed. The effect of various mixing techniques on the distribution of Cremophor EL in the infusion was experimentally evaluated. Different mixing techniques were used to assess their effect on the distribution of Cremophor EL in the solution. RESULTS: Analysis of the preparation techniques of the CsA infusion showed significant correlation between suboptimal mixing of CsA by nurses and the occurrence of anaphylactoid reactions (P = .02). Experimental simulation showed that suboptimal mixing results in an uneven distribution of Cremophor EL, which subsequently sinks to the bottom of the vial. CONCLUSION: Improper mixing of high-dose CsA infusions causes nonsolubilized Cremophor EL to sink to the outflow area of the bottle. An initial bolus infusion of highly concentrated Cremophor EL may produce an anaphylactoid-like response. This mechanism of toxicity is important to recognize, because it is easily preventable by proper preparation of the infusion, thus reducing the incidence of potentially life-threatening anaphylactoid reactions.     

A Photovoltaic C60-Si Heterojunction

A heterojunction was prepared by depositing a thin film of C₆₀ on a p-Si substrate. Photovoltaic properties were observed using a UV-filtered solar simulator and natural sun light. Surface Photovoltage Spectroscopy was employed to distinguish between the nature of photoconversion in the C₆₀ and Si layers.     

Progesterone levels in amniotic fluid and maternal plasma in prostaglandin F2alpha-induced midtrimester abortion

Progesterone concentrations in amniotic fluid and maternal plasma were determined in 11 midtrimester pregnant patients following the intraamniotic administration of prostaglandin F2alpha. Samples were obtained at 3-hour intervals until abortion or spontaneous rupture of membranes occurred or fetal heart tones disappeared. In amniotic fluid, the mean progesterone concentrations increased throughout the sampling period. The plasma progesterone levels declined by about one-third of basal values in the first 3 hours after prostaglandin administration. The paradoxic increase in amniotic fluid progesterone is probably secondary to alterations in uterine blood flow and intrauterine pressure.     

Digitally tunable laser based on the integration of a waveguidegrating multiplexer and an optical amplifier

A novel monolithic semiconductor laser is demonstrated. The optical cavity comprises a 1×N waveguide grating multiplexer connected to N optical amplifiers. By driving a specific output port, laser oscillation is obtained at the wavelength determined by the wavelength path through the multiplexer. Such a laser is very useful for WDM systems because it is capable of producing a comb of precisely spaced frequencies