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Summary form only given. We report on a diode-pumped laser regenerative amplifier design capable of delivering energies in the 100-500 mJ range with good extraction efficiency. We recently demonstrated a 100 mJ regenerative amplifier and we present our latest results in the 300 mJ-500 mJ range. In order to achieve such a high level of energy, several issues have to be faced. First, the pumping energy has to be high. For this reason, we side pump the amplification medium with stacks of 8 diode bars delivering 150 mJ in 400 /spl mu/s, for a peak current of 80 A. We use Nd:phosphate glass as an amplification medium because of its spectral properties but its poor thermal conductivity restricts the laser repetition rate to 1 Hz. At such a low rate, no external cooling is applied to the laser head. Then, the amplification medium size is chosen to achieve a stored fluence of the order of its saturation fluence. This is done to ensure good regenerative amplification. This results in the use of square amplification rods with sizes between 3.5 and 7 mm, depending on the available pumping energies Second, a phase plate is used to shape the laser mode in order to fit at best the amplification rod size and therefore increasing the extraction efficiency. Experimental measurements have shown above 10% energy conversion efficiencies, which is comparable to the results achieved by other pumping strategies.

Purpose: To compare the contrast to noise ratio (CNR) of two different rib suppression methodologies ‐ dual‐energy (DE) image subtraction and blind signal separation (BSS)‐used for lung cancer patients receiving image‐guided radiotherapy. Methods: A database consisting of 28 planar radiographs obtained at 60 kVp and 120 kVp were used in this study. DE subtraction imaging was performed by taking a weighted logarithmic subtraction of the individual images. A weighting parameter of 2.1 was chosen to produce the optimal soft tissue (rib suppressed) images for each image pair. Similarly, BSS was used to extract the soft tissue and bony image components from a patient image. An open source program for performing BSS, called FastICA, was used in conjunction with the same 60 kVp and 120 kVp images. Regions of interest (ROIs) were contoured on the resultant images and the CNR from each technique was calculated and compared. Results: A paired t‐test was run on the CNR values, resulting in a p value 20% higher, and 4 had CNR values > 40% higher. Conclusion: Based on this study, DE image subtraction creates images with higher CNR values than those generated with FastICA. This is likely due, at least in part, to the ability to customize the weighting factor of the DE subtraction images. However, there are numerous methods for performing BSS outside of FastICA, and further study is warranted to determine if alternative BSS methods could produce better rib suppressed images. This research was supported by Varian Medical Systems.

Purpose: To determine the relationship between simulated tumor thickness and signal intensity in a dual energy (DE) subtraction image. Methods: A phantom was constructed using cork (simulating lung), tissue equivalent material, and pork ribs. While keeping the total phantom thickness constant (16 cm), the thickness of cork was varied from 8–12 cm. Simulated tumors with thicknesses ranging from 1–5 cm were placed within inserts inside the cork. Ribs were placed on top of the phantom such that they overlapped the simulated tumor on a planar radiograph. Planar x‐ray images were subsequently acquired using 60 kVp (4 mAs) and 120 kVp (1 mAs) for the various combinations of cork and simulated tumor thicknesses. DE subtraction was performed for each image set to provide rib suppression. Pixel intensity values of the simulated tumor on DE images were obtained and plotted vs. tumor thickness. Results: This study yielded a linear relationship between the simulated tumor thickness and DE pixel value. The relative pixel value increased with increasing tumor thickness. Moreover, the slope was nearly independent of the thickness of cork. The effect of the cork was to shift the intercept, with larger thicknesses of cork resulting in a more negative intercept value. Conclusion: The results of this study illustrate a linear relationship between DE signal intensity and simulated tumor thickness. By demonstrating this relationship, DE imaging may be used as a quantitative means to quickly and efficiently assess 3D tumor response in lung cancer patients. Using this technique, DE imaging may provide a means of screening for patients who are candidates for adaptive radiotherapy. Project supported by a grant from Varian Medical Systems.

Purpose: To characterize the contrast improvement of simulated tumors in an anthropomorphic phantom using Dual Energy (DE) subtraction with a clinical on‐board imager (OBI) at oblique angles. Methods: An Alderson lung/chest anthropomorphic phantom with simulated tumors in the thoracic cavity was imaged using a sequential DE imaging methodology. High (120kVp) and low (60kVp) planar images were obtained in pairs every 100 in a full (3600) rotation using the OBI (Varian Medical Systems, Palo Alto, CA). Optimal mAs settings for DE component images were determined byvarying the x‐ray exposure time, while maintaining a constant tube current. DE images were created to best suppress the bone overlaying the simulated tumors.Tumorvisibility in DE images was quantified using the Contrast‐to‐Noise Ratio (CNR). The ratio of the CNR from the DE image relative to a single image (standard protocol) was evaluated as a function of gantry angle.Results: CNR was improved with DE imaging by an average ratio of 1.66 over all gantry angles. The greatest improvement occurred at gantry angles where the tumor was obstructed by the ribs alone. More modest improvements were observed where the tumor overlapped other soft tissue structures (such as the heart) or the dense spine, on a given projection. Conclusions: This study illustrates the feasibility of performing DE imaging at oblique gantry angles using a clinical on‐board imaging system. Incorporating DE imaging into clinical practice may allow for verification of tumor position at oblique gantry angles, and may facilitate the development of markerless motion tracking techniques. Supported by a grant from Varian Medical Systems.

We report on what we believe is the first experimental demonstration of the linear precompensation of a nonlinear transfer function due to frequency conversion. As a proof of principle, we show the effective precompensation with an interferometric filter of FM-to-AM conversion due to second-harmonic generation in a potassium titanyl phosphate crystal.

A multi-Petawatt high-energy laser PETAL coupled to the Ligne d'Int?gration Laser (LIL) is under construction in the Aquitaine Region in France. This Petawatt laser will be dedicated to academic experiments in the fields of high energy density physics and ultra high intensity. Nd?:?glass laser chain coupled with the chirped pulse amplification (CPA technique allows delivery of high energy. Optical parametric CPA for pre-amplification and a new compression scheme will be implemented. PETAL is designed to deliver 3.6?kJ of energy in 500?fs on a target corresponding to 7.2?PW. The PETAL beam linked to the up to 60?kJ?ns UV beams from the LIL will present new scientific research opportunities.

We propose an original optical architecture for the construction of an Integrated Dumper - Regenerative Amplifier, by combining pulse generation and pulse slicing together with downstream regenerative amplification within a common amplifying unit and resonator. This design provides relatively short pulses at high energy, using a fairly simple and robust two-path resonator. The demonstration is performed with the help of a diode-pumped Yb(3+): YAG slab operated at room temperature at 1Hz PRF, in the energy range of 5 to 50mJ per pulse with 500ps to 5ns FWHM.

9667 Background: Genetic counseling and BRCA testing are largely unavailable to underserved women attending public hospitals because of cost and availability. A gift from Avon Foundation in 2001 en...

9591 Background: California Cancer Registry data from 1997–2001 indicate age-adjusted breast cancer mortality rates (per 100,000) for San Francisco County are highest for African Americans (AA; 43)...

We give an up-to-date description of some present development issues, together with an architecture study and a systems engineering analysis, in the area of laser sources for the injection of the Laser Mega-Joule (LMJ), which are a part of the French ICF fusion program. After a brief description of the main concepts, the overview consists of two parts. The first one includes the standard first source (all-fiber design) that will be used for the activation of the facility of Ligne d'Integration Laser (LIL), the reduced-scale demonstrator under construction for the validation of the concepts and technology to be selected for the LMJ. The second one describes the state of the art in the prototyping of a new source, with extended performance with respect to optical noise and robustness, to be tested on LIL in a second step of the activation.

We report on a side-pumped Nd:phosphate laser regenerative amplifier that delivers laser pulses of as much as 100 mJ in a single TEM mode. The laser beam is mode matched to the amplification medium by an intracavity fused-silica phase plate for mode shaping and a telescope for adjustment of the beam mode to the amplification rod section such that most of the energy stored in the rod is transferred to the laser pulses. As a result of the good overlap and the low loss, an optical-to-optical conversion efficiency of as much as 10% was measured for a pumping current of 80 A and greater than 100-mJ output pulses.

The effects of immune complexes on the antibody response of BALB/c mice to Streptococcus pneumoniae R36a (Pn) were investigated. The cell wall polysaccharide (PnC) extracted from Pn was used to form complexes with TEPC-15, a myeloma protein that binds to phosphorylcholine determinants on the PnC. Complexes formed at equivalence were cultured with splenic T cells from BALB/c mice for 2 d, and then the cells were added to fresh BALB/c spleen cell cultures to test their effect on the antibody response to Pn, a response dominated by the T15 idiotype family. The results indicate that TEPC-15/PnC complexes induced potent suppressor T cells (Ts) whereas cells cultured with free antigen or free antibody alone had no effect on the plaque-forming cell response to Pn. The suppression was specific since the response to control antigens such as sheep erythrocytes was unaffected. The suppression appears to be idiotype-specific since the Ts had a relatively weak (and in some cases no) effect on the anti-Pn response of BALB/c mice that had been suppressed for T15 idiotopes by neonatal injection of a monoclonal anti-T15 antibody, MaId 5-4. Furthermore, cells cultured with TEPC-15/PnC complexes were shown to express specific receptors for TEPC-15 idiotopes. The results indicate that antigen/antibody complexes may have important immunoregulatory effects because they are potent inducers of idiotype-specific Ts.

A continuously operated, 1 pps, dense-plasma-focus device capable of delivering a minimum of 10 15 neutrons per pulse for material testing purposes is described. With I 5 scaling, predicted from analysis of existing machines, yields of 10 16 −10 17 neutrons per pulse are postulated. The average power consumption, which has become a major issue as a result of the energy crisis is shown to be highly favorable. A novel approach to the capacitor bank and switch design allowing repetitive operation is discussed.

Tacitus' phrase sine ira et studio at the start of the Annals (1. 1. 3) is the most memorable claim by an ancient historian that he is free from bias. The same assertion had appeared at the start of his Histories (1. 1. 3), and we find other ancient historians claiming this impartiality for themselves and decrying the lack of it in their predecessors.' The claim is not as widespread as is sometimes stated or implied; but that it was a commonplace by the early Empire is assured when we read, at the start of Seneca's Apocolocyntosis (1. 1), nihil nec offensae nec gratiae dabitur. Polybius is the first extant historian to address the problem of bias directly; it was noted most frequently by those who wrote of the late Republic (e.g., Lucceius, Sallust) and the Empire (e.g., Josephus, Tacitus). Cicero's friend L. Lucceius appears to have made the claim most elaborately: he imagined that he had been tempted by Gratia, just as Hercules had been enticed by Voluptas, and had rejected the temptation, as had the great hero (Fam. 5. 12. 3). 2 Most discussed are the two passages in Tacitus; Joseph Vogt's article "Tacitus und die Unparteilichkeit des Historikers" is perhaps the best known.3 Vogt and other commentators are chiefly concerned to account for the disparity between Tacitus' claim and his failure to fulfill it. The sentiment itself has received scant analysis, evidently because it is assumed that the classical historians meant what we mean when we

The primary antigen-specific antibody response of various strains of mice to TEPC-15/PnC immune complexes has been examined. We found that both BALB/c and C3H mice were good responders to the PnC antigen; however, C3H mice were low responders, whereas BALB/c mice were high responders to the TEPC-15/PnC complexes. Using congenic strains on the C3H and BALB/c background, we have shown that the response to the complexes is not restricted by gene products of the H-2 complex or by the Igh (allotype) locus. However, responsiveness may be controlled by genes linked to the Igh locus, since we have shown that strains that are Ighj, Ighd, and Ighf are low responders, whereas strains that are Igha, Ighb, and Ighe are high responders to the immune complex. Moreover, responsiveness correlates with the expression of the T15 Id as measured using the anti-T15 monoclonal antibody, AB1-2. Thus, strains such as BALB/c, BALB.B, BALB.K, and CB-20, which express high levels of T15 (AB1-2) Id in their PFC response to PnC are relatively high responders to TEPC-15/PnC complexes, whereas C3H, C3H.SW, and C3H-OH, which express low levels of the T15 (AB1-2) Id, are low responders to the complexes. Finally, we found that BALB/c mice are high responders to complexes formed with T15+ antibodies, whereas they are low responders to complexes formed using T15- antibodies. The results suggest that the antigen-specific response to these immune complexes is Id-restricted.

In order to get reliable and synchronisable smooth nanosecond range pulses, a high stability singlemode actively Q-switched laser oscillator has been developed which works with Nd:YAG or Nd:YLF. An electronic loop is used for longitudinal mode control. It is based on dual-mode beating detection and the design is mainly numerical. The system produces 10 pps jitter free pulses with ±2% amplitude stability and 100% singlemode spectral limitation. The method is equally suitable for producing repetitive dual-mode modulated pulses.

An integrated work shift scheduling system is developed and applied in the scheduling of 2600 telephone operators in 43 locations of the General Telephone Company of California. The system involves the forecasting of calls on a half-hourly basis, the conversion to operator requirements, the scheduling of tours by a heuristic algorithm, the assignment of operators to tours, and the operation of the system.

About iio B.C. the "Roma" head on the obverse of Roman silver coins began to disappear in favor of a variety of deities and legendary heroes. In little more than a decade the type had been almost completely supplanted and appeared thereafter on the issues of only ten moneyers down to the death of Julius Caesar. The busts which replaced the "Roma" head were many and varied; over fifty different types can be catalogued between ca. iio and 44 B.c. Some appear but once or a few times; others, such as Jupiter, Juno, and Mars, are featured in regular and consistent distribution. But three deities are not: Apollo, Venus, and a young god whose chief attribute is a thunderbolt and who has been variously identified as Veiovis or as the "young Jupiter." The purpose of this paper is to investigate the heavy concentration of these types.

Target identification remains a challenge for the field of chemical biology. We describe here an integrative chemical genomic and proteomic approach combining the use of differentially active analogs of small-molecule probes with stable isotope labeling by amino acids in cell culture (SILAC)-mediated affinity enrichment, followed by subsequent testing of candidate targets using RNA interference (RNAi)-mediated gene silencing. We applied this approach to characterizing the natural product K252a and its ability to potentiate neuregulin-1 (Nrg1)/ErbB4 (v-erb-a erythroblastic leukemia viral oncogene homolog 4)-dependent neurotrophic factor signaling and neuritogenesis. We show that AAK1 (adaptor-associated kinase 1) is a relevant target of K252a, and that the loss of AAK1 alters ErbB4 trafficking and expression levels providing evidence for a previously unrecognized role for AAK1 in Nrg1-mediated neurotrophic factor signaling. Similar strategies should lead to the discovery of novel targets for therapeutic development.

The capability of a thin slab of Yb3+:LSO to be tuned within a Q-switched cavity is demonstrated in a range of laser wavelengths from 1052 to 1065 nm. Using a side-pump architecture, to create a linear gain-stripe in the crystal of which the dimensions can be finely controlled, we generate 50 to 150 ns-wide pulses in the range 1–5 mJ. These experimental data are fitted with the theoretical predictions by means of comprehensive modeling. Our model involves all the relevant parameters for the discussion of energetic, spectral and spatial issues of interest to evaluate the potential of this quasi-three-level material in the field of broadband regenerative amplification. Thanks to pure homogeneous broadening, this finally helps us to size a consistent pump design dedicated to the amplification of broad-bandwidth pulses up to a few milli-joules near 1053–1056 nm, the range of wavelengths involved in ICF.

Beginning in 1974, patients undergoing mastectomy at high risk for recurrence (greater than or equal to 4 nodes positive; median, 9.4 positive; range, 4 to 28) were randomized after stratification for menopausal status and radiotherapy to receive either 5-fluorouracil (5-FU, 500 mg/sq m i.v. every week) or cyclophosphamide, 400 mg/sq m; methotrexate, 30 mg/sq m; and 5-FU, 500 mg/sq m (CMF; all given i.v. every 2 weeks) in a 12-month program. All 62 patients remain evaluable with median follow-up now exceeding 70 months (range, 60 to 80 months). CMF significantly prevented early disease recurrence (97% relapse free on CMF versus 75% on 5-FU at 12 months; p less than 0.05) and demonstrated survival advantage during the initial 40-month follow-up. This significance was subsequently lost, and the percentages of relapse free and overall survival after 70 months are: (formula, see text) The apparently paradoxical relationship between relapse and survival on the 5-FU arm was related to survival after recurrence. Survival after recurrence was significantly longer on the 5-FU compared to the CMF arm (median of greater than 38 versus 10 months, respectively; p less than 0.01). These results suggest (a) long-term survival in adjuvant trials cannot be accurately predicted by short-term differences in relapse frequency, (b) survival after relapse may be influenced by the antecedent adjuvant therapy received, and (c) disease relapse does not necessarily preclude long-term survival.

This report describes a 1 pulse per second, dense-plasma-focus (DPF) materials-testing device capable of delivering a minimum of 10$sup 15$ neutrons per pulse. Moderate scaling up from existing designs is shown to be sufficient to provide 2 x 10$sup 13$ neutrons/ cm$sup 2$. s to a suitable target. The average power consumption, which has become a major issue due to the energy crisis, is analyzed with respect to other plasma devices and is shown to be highly favorable. Also discussed is a novel approach to capacitor-bank and switch design with respect to repetitive-pulse operation. (auth)