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The relativistic magnetron is one of the most attractive high-power microwave sources, due to its compactness with high efficiency. It can generate hundreds of megawatts of microwave power in the L- and S-bands. However, the efficiency of the magnetron is often limited due to the mode stability. In this Letter, three-dimensional particle-in-cell simulation suggests even further increase of total efficiency of the magnetron can be realised via mode stabilisation using a self-excited extended interaction in a collector region. A six-vaned radial relativistic magnetron with a single radial output port powered by 400 kV, 900 MW with an efficiency of ∼48%. This improvement is attributed to the mode locking of operating π-mode by a power-boosted TE315 mode excited in the extended cavity.

Rice (Oryza sativa L.) is one of the most important food crops in the world. However, rice paddy fields are considered as one of the major sources of anthropogenic CH4 emissions. The objectives of this study were to estimate CH4 fluxes from a rice paddy field during rice growing seasons in South Korea and to assess the impacts of water managements on reduction of CH4 emissions using a process-based model. Three CH4 flux monitoring chamber systems installed at a rice paddy field in Gimje (South Korea) were used to measure CH4 fluxes. These measured datasets were used to evaluate the performance of the Denitrification–Decomposition (DNDC) model to simulate CH4 fluxes. A mid-late maturing rice cultivar (Shindongjinbyeo) was transplanted with a planting density with 0.15 m × 0.30 m (hill × row) on June 21, 2012 and June 21, 2013 after barely had been harvested at the study site. The DNDC model underestimated CH4 fluxes from a rice paddy field at the beginning of the rice growing seasons (overall 0.7 of R2 for the year 2013), while the DNDC model well-estimated CH4 emissions during the rice growing seasons. The DNDC model was used to assess the impacts of continuous flooding and midseason drainage on CH4 emissions. This study suggests that the DNDC model can be used to assess efficacious mitigation strategies to reduce the greenhouse gases.

Background Magnetic resonance imaging (MRI) is a sensitive and useful method for the detection of synovitis and joint destruction in rheumatoid arthritis (RA) patients. However, the patterns of MRI-detected bone erosion, bone marrow edema (BME), synovitis, and tenosynovitis have received insufficient attention. Objectives Therefore, this study evaluated the patterns of bone erosion, BME, synovitis, and tenosynovitis, and calculated the RA-MRI score (RAMRIS) of patients with RA at the carpal and metacarpophalangeal (MCP) joints using MRI. Methods MRI datasets from 43 RA patients were analyzed. All patients had undergone MRI of one wrist. In addition, 36 patients had MCP joint images taken, and 3 had also received MRI of the contralateral wrist and MCP joints. The MR images were evaluated for bone erosion, BME, and synovitis in consensus by 2 blinded readers according to the OMERACT RA-MRI score (RAMRIS). The MRI-detected tenosynovitis was evaluated based on Haavardsholm9s tenosynovitis score. Results The capitate, lunate, triquetrum, and hamate bones were the most common sites of erosion and BME and showed the highest RAMRIS erosion and BME scores. Moreover, MRI-detected tenosynovitis was present in 78.3% of all patients with RA, and the extensor compartment 4 and flexor digitorum profundus and superficialis were frequently affected. Conclusions This study identified the distribution and prevalence of MRI-detected bone erosion, BME, synovitis, and tenosynovitis of the wrist and MCP joints in RA patients. The patterns of the MRI-detected abnormalities may help to select sites for the application of MRI protocols in clinical trials and practice. References Ejbjerg B, McQueen F, Lassere M, Haavardsholm E, Conaghan P, O9Connor P, et al. The EULAR-OMERACT rheumatoid arthritis MRI reference image atlas: the wrist joint. Annals of the rheumatic diseases. 2005;64 Suppl 1:i23–47. Ostergaard M, Edmonds J, McQueen F, Peterfy C, Lassere M, Ejbjerg B, et al. An introduction to the EULAR-OMERACT rheumatoid arthritis MRI reference image atlas. Annals of the rheumatic diseases. 2005;64 Suppl 1:i3–7. Conaghan P, Bird P, Ejbjerg B, O9Connor P, Peterfy C, McQueen F, et al. The EULAR-OMERACT rheumatoid arthritis MRI reference image atlas: the metacarpophalangeal joints. Annals of the rheumatic diseases. 2005;64 Suppl 1:i11–21. Haavardsholm EA, Ostergaard M, Ejbjerg BJ, Kvan NP, Kvien TK. Introduction of a novel magnetic resonance imaging tenosynovitis score for rheumatoid arthritis: reliability in a multireader longitudinal study. Annals of the rheumatic diseases. 2007;66(9):1216–20. Acknowledgements The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. Disclosure of Interest None declared

Background: Black and Latina women have lower rates of return to work than non-Latina whites (NLW) after breast cancer treatment. We recently showed that stopping work during chemotherapy is associated with not returning to work for 5 years after treatment. Little is known about the impact of breast cancer on employment outcomes in other low-English proficiency (LEP) immigrant or minority groups. The ongoing longitudinal Breast Cancer and the Workforce study measures work status in LEP immigrants and ethnic minorities undergoing breast cancer treatment with curative intent. For this pilot, we assessed work status and financial stability during treatment. Methods: Women aged 18–64, undergoing treatment for stage I-III breast cancer, employed at diagnosis, and able to consent in English, Korean, Mandarin, or Spanish were recruited at 3 community oncology clinics and an NCI-designated cancer center. Participants enrolled any time prior to completing their last treatment (chemo, XRT, or surgery) and self-administered web surveys with in-person assistance, as needed, in their preferred language. Demographic, financial, and pre- and post-diagnosis employment characteristics were analyzed using descriptive statistics. Results: The sample (n = 61) median age was 48 years. 20 (33%) were black, 14 (23%) NLW, 11 (18%) Latina, 8 (13%) Korean, 7 (12%) Chinese, and 1 (2%) other. 37 (61%) were foreign born, 35 (58%) had When surveyed, 25 (41%) were working full time, 11 (18%) part time and 25 (41%) not working (13% on disability, 16% on paid sick leave, 12% other). 31 (51%) changed work status – stopped working or reduced hours. Of pre-diagnosis full-time workers (n = 47), 23 (49%) changed work status – 4 (9%) to part-time, 8 (17%) sick leave, 7 (15%) disability and 4 (9%) stopped working. Of pre-diagnosis part-time workers (n = 13), 6 (46%) changed status – 2 (16%) sick leave, 1 (8%) disability and 3 (23%) stopped working. Overall, 26 (43%) had less money to spend on food since starting treatment; 31 (53%) did not have enough money to cover their needs. Discussion: In this pilot, 51% of women changed work status during breast cancer treatment. 41% stopped working, of whom almost a third did not have sick leave or disability. 43% experienced food insecurity during treatment, and 53% said they did not have enough money to cover their needs. Additional research is needed to understand the factors that disrupt work during or soon after treatment, how these factors vary for low-income and minority groups, and to better define the impact of change in work status on financial stability. Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-11-05.

High-strain-rate superplastic behavior of powder-metallurgy processed 0%, 10%, 20%,and 30% SiC particulate reinforced 6061 Al composites was studied over a range of temperatures from 430 to 610 °C. The strength of the 6061 Al composites was lowerthan that of the 6061 Al matrix alloy in the temperature range where grain boundarysliding is believed to control the plastic flow. The difference in their strength was alsoobserved to be temperature dependent, increasing with increase in temperature.Abnormally high activation energy for superplastic flow was another important featureof the 6061 Al composites. These behaviors in particle weakening and activationenergy have strong resemblance to those noted in the high-strain-rate superplastic 2124Al composites studied previously. The observed particle weakening was attributed toliquid-enhanced superplastic flow and discussed by adopting the concept of effectivediffusivity considering mass flow through liquid phase formed at the solute-segregatedregion near SiC/Al interfaces.

Most of the p53 target genes, all except MDM2, COP1 and PIRH2, perform functions in apoptosis, differentiation and cell cycle arrest. The aforementioned oncogenes downregulate p53 through a negative feedback mechanism, and thus contribute to tumor development. In this study, we report a new p53 target, PRL-1, which is believed to be a significant regulator in the development and metastasis of a variety of cancer types. Phosphatase of regenerating liver 1 (PRL-1) overexpression reduced the levels of endogenous and exogenous p53 proteins, and inhibited p53-mediated apoptosis. On the other hand, the ablation of PRL-1 by small interfering RNA (siRNA) increased p53 protein levels. The p53 downregulation was mediated by p53 ubiquitination and subsequent proteasomal degradation. Furthermore, p53 ubiquitination by PRL-1 was achieved through two independent pathways, by inducing PIRH2 transcription and by inducing MDM2 phosphorylation through Akt signaling. In addition, we showed that the PRL-1 gene harbors a p53 response element in the first intron, and its transcription is regulated by the p53 protein. These findings imply that the new oncogenic p53 target, PRL-1, may contribute to tumor development by the downregulation of p53 by a negative feedback mechanism.

A Relativistic backward wave oscillator (RBWO) is a reliable source of a high power electromagnetic wave (HPEM). The RBWO is capable of high efficiency by a relatively long interaction region between a backward wave and an electron beam. But the pulse shortening problem occurs frequently in experiments of RBWO because of the mode competition, the RF breakdown and so on. After this mode competition between axial modes of TM01, the RF power is vanished. There also occurs a mode competition between TM01 and TM02 when the radii of the hollow electron beam are smaller than a critical value. Mode competition which is one of the main causes of pulse shortening is found to be very sensitive to the position of the electron beam in this RBWO device. Experimental study is done on 100MW RBWO and in progress on X-band hundreds MWRBWO.

Lignocellulosic biosorbents, including juniper fiber, show promise as sorbents for removing pollutants from wastewater run-off because of their low cost. In this study, juniper fiber modified with iron species from acid mine drainage (AMD) was tested for its capacity to remove phosphorus from water compared to unmodified juniper fiber. In batch tests, the maximum adsorbate loading (Qmax) of phosphorus onto the modified adsorbent was 1.83 mg g(-1) at pH 4.0, obtained by fitting the isotherm results to the Langmuir isotherm model. This value is similar to the sorption capacity of other conventional adsorbents such as goethite, which implies that the modified lignocellulosic material would be effective as a sorbent for removing phosphorus from water. In the kinetic test, the pseudo-second order kinetic model fitted well the sorption of phosphorus onto the modified filter medium, showing the kinetic constant (k) of 8.09 x 10(-2) g(mg min)(-1) at initial phosphorus concentration of 10 mg l(-1).

Exact simulation of conducted EMI in switched mode power supplies is proposed. In order to achieve exact simulations, PSPICE active component ABM model and modified transformer model are proposed. Each model parameter is extracted from measurements and databooks. PSPICE simulation results with high frequency PCB pattern model are accordant with EMI measurements for a 50[W] isolated flyback converter. EMI relations of each component and EMI patterns are analyzed. INTRODUCTION Recently EMI (Electro-Magnetic Interference) / EMC regulations such as FCC, VDE, CISPR are tighter than ever. Exact prediction of EMI can help designer to satisfy EMI regulations cheaply and cope with EMI problems easily before making hardware. In recent years, many EMI prediction methods have been proposed. Most methods are time domain simulations focused on special points such as passive components, active device, and PCB pattern [3][4]. Some method uses spectral analysis of noise sources such as transistor and diode [5]. These methods, however, could not analyze interactions of system components. In addition, some method needs system hardware. The purpose of this paper is to develop a modeling tool for an exact simulation of conducted EMI noise of switched mode power supplies, and to analyze EMI effects due to the interactions of system components. For this purpose, the following high frequency (150kHz~30MHz) component models need to be developed. (1) Active component models (switches, diodes, etc.) (2) Passive component models (transformer, capacitor, inductor, resistor, etc.) (3) Printed Circuit Board (PCB) pattern model With these models, a 50 W isolated flyback converter’s EMI pattern is simulated and compared with the hardware measurements. EMI interactions of each component and EMI patterns are analyzed. HIGH FREQUENCY COMPONENT MODELING ACTIVE COMPONENT MODELING Active components such as switches and diodes are main noise sources in switched mode power supplies. Especially, the parasitic ringing voltage and current of the switches affect EMI pattern severely. Therefore, an exact active component model to predict accurate ringing frequency, amplitude, overshoot, and rising / falling transient is needed. However, use of commercial simulation software such as PSPICE is difficult because of limited library models available and inaccuracy of model parameter values for the purpose of EMI simulation. To obtain an exact model for the tested device, an equation-oriented ABM (Analog Behavioral Model) was developed. This ABM model is composed of characteristic equations of MOSFET and diode. This model use characteristic curves of data-sheet to extract model parameters. Figure 1 shows the MOSFET ABM model. MOSFET model includes two parts. One part is the model of the DC transfer-function characteristics. The other part is the model of the body diode and the parasitic capacitances ( Cgs, Cgd, Cds ). The DC transfer-function model of MOSFET realizes the characteristic of turn-on and off. Equation (1.a) represents turn-off characteristic. Equation (1.b) represents turn-on characteristic in the saturation region. Equation (1.c) represents turn-on characteristic in the linear region. Equations (1.d) and (1.e) represent the drain saturation voltage and current. Figure 2 shows the PSPICE ABM model for the DC transfer characteristics using eq. (1.a ~ 1.e)[7][8]. The parasitic capacitance model of MOSFET is an important factor because the parasitic capacitances make resonant oscillations with system inductances. Drain to source capacitance is modeled as the junction capacitance of the body diode. The body diode model must represent non-linear capacitance characteristics according to the reverse voltage. PSPICE diode model is used as the body diode model of MOSFET. Equation (2.b) represents the drain to source capacitance. In general, gate to source capacitance can be modeled as a constant value capacitance. Gate to drain capacitance characteristic curve is non-linear and discontinuous. In order to realize a simple model, an approximated continuous characteristic curve is used as shown in Figure 3. Eq. (3.a ~ 3.c) represents the gate to drain capacitance. Figure 4 shows the PSPICE ABM model for the capacitances using eq. (2.a ~ 3.c). Figure 5 illustrates the modeling procedure and table 1 summarizes the model parameters and their values for the IRF 840 MOSFET.

The growth-promoting and metabolic effects of recombinant ovine placental lactogen (oPL) were compared with those of recombinant bovine growth hormone (bGH) in young lambs. Lambs were treated by twice daily subcutaneous injection with oPL (n = 16) or bGH (n = 16) at a dose of 0.1 mg/kg live weight/day or with saline (n = 16) for 21 days commencing on day 3 of life. Jugular blood samples were taken on days 0, 10 and 20 of treatment. Half the lambs in each group were slaughtered at 24 days, and the other half at 9 months of age. Both bGH and oPL treatments induced small but significant (P0.05) increases in circulating concentrations of insulin-like growth factor-I (IGF-I) on day 10 of treatment, but not on day 20. Neither treatment altered plasma concentrations of glucose, non-esterified fatty acids, urea or creatinine compared to those in saline-treated lambs. Relative to those of bGH-treated (0.24 +/- 0.01 kg/day) or saline-treated (0.25 +/- 0.01 kg/day) lambs, live weight gains of oPL-treated lambs (0.28 +/- 0.01 kg/day) were significantly (P0.05) increased during treatment and differences in live weight were still apparent at 9 months of age. Similarly, treatment with oPL, but not bGH, significantly (P0.01) increased daily energy intake. It is concluded that placental lactogen and growth hormone do not have identical biological actions. While oPL is growth-promoting in young lambs, this effect may be mediated by stimulating voluntary feed intake rather than by elevating circulating concentrations of IGF-I.

The role of placental lactogen (PL) in the regulation of maternal metabolism and fetal growth is not understood. Both PL and growth hormone (GH) have been suggested as possible regulators of mammogenesis. Our aim was to compare the effects of recombinant ovine placental lactogen (oPL) and bovine growth hormone (bGH) on maternal mammary gland development and fetal growth. Pregnant ewes were treated from day 101 to 107 of gestation with twice daily subcutaneous injections of recombinant oPL (n = 7), bGH (n = 8) (0.15 mg/kg live weight/day) or saline (n = 8). On day 108 of gestation, fetal and maternal tissues were collected. The relative abundance of growth hormone receptor (GHR), insulin-like growth factor-1 (IGF-1) and insulin-like growth factor binding protein-3 (IGFBP-3) mRNA was assessed in mammary gland, maternal liver and heart, and in fetal and placental tissues. There was no detectable change in mammary tissue GHR, IGF-1 or IGFBP-3 gene expression with either bGH or oPL treatment. Maternal administration of bGH, but not oPL, during pregnancy caused an increase in maternal hepatic IGF-1 gene expression (P0.005). Treatment with oPL, but not bGH, resulted in a significant increase (P0.025) in the relative abundance of fetal hepatic IGFBP-3 mRNA. Maternal hepatic GHR gene expression was not affected by treatment. This study suggests that while bGH treatment of pregnant ewes induces characteristic somatogenic responses, oPL treatment does not have comparable effects. However, oPL may indirectly influence the fetal somatotropic axis by altering fetal hepatic IGFBP-3 production.

The influence of pH, temperature and various electron-donators on the nitrate reductase activity of Paracoccus denitrificans DSM 65 was investigated. Nitrate reduction rate was studied in a model solution and in carrot juice. The denitrifying efficiency of P. denitrificans DSM 65 depended on pH, temperature and mainly on the H donator. Enzyme activity was highest at 34°C, pH 7.0 and with fructose as H donator. Fructose has been found to have the greatest influence on nitrate; with fructose as H donator, the specific nitrate degradation rate was twice to three times as high as with glucose or sucrose. At the higher temperatures and pH values the nitrate degradation rate increased as well. This applied to both model solution and carrot juice.

The objective of this study was to investigate the role of amylin (a pancreatic hormone) in regulating metabolism in support of lactation. Rat amylin was infused (320 pmol.kg LW(-1).h(-1)) for 6 h via an external pudic (mammary) artery into six lactating goats. This dose of amylin led to a sixfold increase in plasma concentrations of amylin relative to baseline. Amylin infusion increased plasma concentrations (jugular) of glucose and NEFA up to 16 and 168%, respectively, relative to saline infusion. In contrast, plasma concentrations of Ca and PO4 during amylin infusion were reduced by 18 and 30%, respectively, relative to saline infusion. Plasma concentrations of IGF-I, insulin, and Mg were not different between the two treatments, although IGF-I concentrations in the amylin-infused group, 1 and 6 h postinfusion, were significantly higher than those in the saline-infused group. Similarly, amylin infusion failed to affect milk yield and major constituents of milk except protein; milk protein content decreased progressively until the end of amylin infusion and remained low thereafter. Amylin also had no effect on minerals in milk (Ca, PO4, Mg, Fe, Sr, S, K, or Na) except Zn, which was significantly decreased from 56.8+/-5.8 micromol/L at 0 h to 44.5+/-2.4 micromol/L at 6 h postinfusion. Mammary blood flow (measured with a transit-time blood flow probe) increased up to 26% during amylin infusion, although this effect lasted only for the first 3 h. In conclusion, amylin increased plasma concentrations of glucose and NEFA, and mammary blood flow, while decreasing plasma concentrations of Ca and PO4. Despite these metabolic changes, amylin infusion did not increase milk yield of lactating goats.