Magnetoplasmons in quasineutral epitaxial graphene nanoribbons

We present an infrared transmission spectroscopy study of the inter-Landau-level excitations in quasineutral epitaxial graphene nanoribbon arrays. We observed a substantial deviation in energy of the L(0(-1)) → L(1(0)) transition from the characteristic square root magnetic-field dependence of two-dimensional graphene. This deviation arises from the formation of an upper-hybrid mode between the Landau-level transition and the plasmon resonance. In the quantum regime, the hybrid mode exhibits a distinct dispersion relation, markedly different from that expected for conventional two-dimensional systems and highly doped graphene.

Feeding Artemisia annua alters digesta pH and muscle lipid oxidation products in broiler chickens

Because of growing consumer concern about the use of antimicrobials and the ban on most antibiotic feed additives in the European Union, there is increased interest in using alternatives to antimicrobials in poultry diets. Dried leaves of Artemisia annua have been used in Oriental medicine due to their antimicrobial activities. In the current study, the effect of including A. annua in broiler diets on hindgut and ceca pH, lipid oxidation products, and phenolic content of dark and white meat, and bird performance were investigated. A total of 96 broiler chicks were kept in 48 cages. Two cages with 2 birds per each cage are considered as 1 replicate, and there were 8 replications per treatment. The birds were fed corn-soy diets containing 0% (control), 2% (ART2), or 4% (ART4) dried A. annua leaves from d 14 through d 42. Cecal digesta pH was the lowest in birds fed the ART4 diet (P < 0.02), whereas the pH of ileal digesta was the lowest in ART2 (P < 0.01). Lipid oxidation products measured as TBA reactive substances (TBARS) were lower in the breast and thigh muscle of birds fed ART2 and ART4 diets compared with the control (P < 0.0001). No difference was found in total fat content of the liver, abdominal fat pads, or breast or thigh muscle content (P > 0.05). Artemisia annua addition did not affect final BW, weight gain, feed consumption, carcass weight, or feed:gain. No difference was observed in the relative weight of liver, abdominal fat, spleen, or heart tissue. Gastric acidity is protective against intestinal colonization and translocation of pathogenic bacteria. Therefore, gut pH and muscle tissue TBARS reduction in birds fed ART2 and ART4 suggest that A. annua may prove useful as a natural phytogenic feed additive with antioxidant potential that could be incorporated into poultry diets.

Actigraphy monitoring of symptoms in patients with Parkinson's disease

Although the Unified Parkinson's Disease Rating Scale (UPDRS) is the "gold-standard" tool in assessing the severity of symptoms in patients with Parkinson's disease (PD), not all activity-related disease symptoms can be accurately captured by the well-established clinical rating scale. Using an alternative approach, this study examined the level of physical activity measured by actigraphy over time and whether change in physical activity was associated with disease severity assessed by UPDRS. We used a longitudinal design in which physical activity and disease severity were assessed repeatedly during a 4-month interval, over a 3-year observational period, in a sample of 61 patients with idiopathic PD and a control group of 32 neurologically intact individuals. Physical activity data during awake-time were analyzed using the power-law exponent (PLE) method. Correlational relationships between changes in maxima values of PLE and scores of total UPDRS, UPDRS-part II (Activities of Daily Living), and UPDRS-part III (Motor Examination) in patients with PD were examined. Results show an increase in maxima values of PLE and the UPDRS total score in PD patients and that there is a positive association between changes in maxima values and total UPDRS score (r=0.746, p=0.032), UPDRS-part II score (r=0.687, p=0.027), and UPDRS-part III score (r=0.893, p=0.018). There was no significant change in the level of physical activity over time for the controls. Findings from this study indicate that change in physical activity, as captured by actigraphy, is associated with increased severity in patients' clinical symptoms of PD over time. Thus, these data suggest that, when used in conjunction with the conventional UPDRS measure, an actigraphic measure of physical activity may provide clinicians an adjunct measurement approach to monitor patients' activity-based disease progression or responses to treatment in outpatient clinic settings.

Photonic generation of phase-coded microwave signals with tunable carrier frequency

A photonic scheme to generate a phase-coded microwave signal with tunable carrier frequency based on a simple single-trip and two-pass structure is proposed. Facilitated by the fiber Bragg grating and phase modulator along the trip, both frequency doubling and signal phase coding could be achieved simultaneously. Phase-coded microwave signals at 20 and 22 GHz are experimentally generated.

Photonic arbitrary waveform generation based on crossed frequency to time mapping

Microwave photonic arbitrary waveform generation based on incoherent frequency-to-time-mapping (FTTM) accompanied by intersymbol interference, so called crossed FTTM (CFTTM). The pulse shape can be defined and tuned by properly adjusting the spectrum shaper (symbol shape) and the degree of intersymbol interference. UWB-, triangular-, rectangle-, comb- and user-defined pulse shapes are experimentally obtained.

Peripheral blood CD40-CD40L expression in human breast cancer

BACKGROUND

Breast cancer is the most common cancer in women. T cell-based immunotherapy for cancer has attracted much attention recently. CD40 and CD40L occupy an important position of specific immune response. In this paper, we want to study the role of co-stimulatory molecules CD40/CD40L and their clinical significance in peripheral blood of patients with breast cancer.

METHODS

Thirty breast cancer patients served as observation group, who were diagnosed as having infiltrating ductal breast cancer histopathologically, and 30 healthy as control group. Flow cytometric analysis was conducted to detect the expression of CD40 and CD40L on B and T lymphocytes in peripheral blood. The relationship between the CD40/CD40L expression levels and pathological grades was analyzed.

RESULTS

The expression levels of CD40/CD40L on B cells and T cells in breast cancer patients were significantly higher than those in the controls (all P < 0.001), and CD40/CD40L levels had a significant positive relationship with pathological grades (all P < 0.001).

CONCLUSIONS

The upregulated levels of co-stimulators CD40/CD40L on B cells and T cells may play an important role in the immune pathogenesis of breast cancer.

Laparoscopic versus open surgery for rectal cancer: a clinical comparative study

OBJECTIVE

To compare short-term surgical outcomes and long-term survival following laparoscopic or open resection for rectal cancer.

METHODS

A total of 381 patients undergoing laparoscopic surgery and 276 undergoing open surgery for curative resection of rectal cancer were included. Long-term survival and peri- and postoperative data were retrospectively reviewed from a prospectively-collected database.

RESULTS

Surgical groups were comparable regarding age, gender, tumour stage and preoperative comorbidities. Laparascopic surgery was associated with significantly longer duration of surgery, less intraoperative blood loss and fewer postoperative infections than open surgery. Patients who underwent laparoscopic resection had significantly earlier recovery of gastrointestinal function than those who underwent open surgery. There were no significant between-group differences in number of lymph nodes excised, specimen length or distal margin. The 3- and 5-year survival rates and overall survival were similar in the two groups, and survival was not influenced by tumour location.

CONCLUSION

Laparoscopic surgery can achieve the same oncological results as open resection in patients with rectal cancer, supporting its continued use in the management of this disease.

Bandwidth improvement for slow light using amplification characteristics of cascaded vertical-cavity surface-emitting lasers

A scheme to improve the bandwidth of slow light using cascaded vertical-cavity surface-emitting lasers (VCSELs) is proposed and experimentally demonstrated. In the scheme, a proper adjustment on the gain peaks of two cascaded VCSELs enables the generation of the desired composite gain spectrum, which has flat-top gain and delay profiles with enhanced peak values. By employing the improved gain and delay profiles in a slow light system, a large delay can be achieved within a wider bandwidth. In the experiment, by using two cascaded VCSELs, a tunable slow light up to 135 ps for a 5 Gbits/s pseudorandom binary sequence is demonstrated with relatively low signal distortion.

Photonic generation of impulse ultrawideband signals with switchable shapes and polarities based on frequency-to-time mapping

A photonic approach to generate impulse ultrawideband (UWB) signals with switchable shapes and polarities based on the frequency-to-time mapping technique is proposed and demonstrated. UWB monocycle, doublet, and triplet signals with two polarities can be obtained by adjusting the switchable spectrum shaper.

Two new naturally occurring optical polyacetylene compounds from Torricellia angulata var intermedia and the determination of their absolute configurations

Four compounds were isolated from Torricellia angulata var intermedia (Harms.) Hu (Torricelliaceae), followed by formation of derivatives, which gave two new polyacetylene compounds 3 and 4 with respectively a chiral carbon center whose absolute configurations were determined unambiguously by the recently developed extended Mosher's method. This is the first time to obtain natural polyacetylenes possessing a chiral hydroxyl group.

PDM RZ-to-NRZ and NRZ-to-PRZ format conversions using a variable DGD element inside a polarization-diversified loop

A novel scheme for bit-rate-variable polarization-division-multiplexed return-to-zero to nonreturn-to-zero and NRZ to pseudo-return-to-zero format conversions is proposed using a variable differential-group-delay element inside a polarization-diversified loop. Conversion for both 2×10 and 2×12.5 Gbit/s PDM signals are successfully demonstrated with approximately 1 dB additional power penalty by properly adjusting DGD values of the variable DGD element.

Spin transition in the ν=8/3 fractional quantum Hall effect

We present here the results from a density dependent study of the activation energy gaps of the fractional quantum Hall effect states at Landau level fillings ν=8/3 and 7/3 in a series of high quality quantum wells. In the density range from 0.5×10(11) to 3×10(11) cm(-2), the 7/3 energy gap increases monotonically with increasing density, supporting its ground state being spin polarized. For the 8/3 state, however, its energy gap first decreases with increasing density, almost vanishes at n~0.8×10(11) cm(-2), and then turns around and increases with increasing density, clearly demonstrating a spin transition.

Simultaneous all-optical RZ-to-NRZ format conversion for two tributaries in PDM signal using a single section of highly nonlinear fiber

Simultaneous all-optical RZ-OOK to NRZ-OOK format conversion for two tributaries in PDM signal is demonstrated utilizing a single section of highly nonlinear fiber through polarization nonlinear loop mirror configuration. Less than 1-dB power penalty is achieved in a 2 × 12.5-Gb/s PDM system, and only 1.4-dB SNR penalty is obtained in a 2 × 40-Gb/s PDM system.

Fangchinoline induces autophagic cell death via p53/sestrin2/AMPK signalling in human hepatocellular carcinoma cells

BACKGROUND AND PURPOSE

Fangchinoline is a novel anti-tumour agent with little known of its cellular and molecular mechanisms of action. Here we have investigated the mode of cell death induced by fangchinoline and its underlying mechanism in two human hepatocellular carcinoma cell lines, HepG2 and PLC/PRF/5.

EXPERIMENTAL APPROACH

Apoptosis and autophagy were monitored in fangchinoline-treated HepG2 and PLC/PRF/5 cells by histological methods. The signal transduction pathways involved in activation of autophagy were examined, using immunoblotting, real-time PCR and siRNA techniques.

KEY RESULTS

Fangchinoline did not induce apoptosis in HepG2 and PLC/PRF/5 cells but triggered, dose-dependently, autophagy, an alternative mode of cell death which may contribute to fangchinoline's anti-tumour action. Nuclear translocation of p53 was involved in induction of autophagy by fangchinoline, followed by selective transactivation of the autophagy-related gene sestrin2 and initiation of the autophagic process. Signalling by the AMP-activated protein kinase was also involved as a downstream target of sestrin2 and induced mTOR-independent autophagic cell death in both cell lines. siRNA for Atg 5 or pharmacological block of p53 abolished fangchinoline-induced autophagy and inhibition of autophagy switched cell death to apoptosis in these cells, suggesting that cell death is irreversible once autophagy is induced by fangchinoline.

CONCLUSIONS AND IMPLICATIONS

Fangchinoline is a highly specific agent inducing autophagic cell death in hepatocellular carcinoma cells with a novel mechanism, which elucidates the potential of fangchinoline to potentiate programmed cell death in cancer cells.

Screening for the interacting partners of the proteins MamK & MamJ by two-hybrid genomic DNA library of Magnetospirillum magneticum AMB-1

Magnetotactic bacteria are a group of prokaryotes capable of sensing and navigating along the earth's magnetic field. The linear alignment of magnetosomes, which acts as a compass needle for orientation, is dependent on the proteins MamJ (amb0964) & MamK (amb0965). We constructed Magnetospirillum magneticum AMB-1 two-hybrid DNA libraries by fusing the random genomic fragments of AMB-1 to the N-terminal domain of the α-subunit of RNA polymerase in vector pTRG and used as preys. The genes mamJ & mamK were cloned in frame with the λ repressor protein (λ cI) in vector pBT and used as baits for screening the binding partners. After preliminary screening, we further confirmed the candidate interactions between selected protein pairs. The results showed that there were relatively strong interactions between MamK versus Amb3498 (flagella motor switch protein fliM), versus Amb0854 MCPs (signal domain of methyl-accepting chemotaxis protein) and versus Amb3568 (GGDEF domain-containing protein), respectively. MamJ versus Amb1722 (hypothetical protein), MamJ versus MamK, and MamK versus Amb1807 (cation transport ATPase) exhibited low level of interaction. Although the TPR repeat protein MamA (amb0971) showed no interaction with either MamJ or MamK, the TPR repeat protein Amb0024 with more motif sequences exhibited relatively strong interaction with MamK. Among the identified proteins, all categorized as signal transduction-related displayed interaction only with MamK and without MamJ, suggesting that magnetotaxis via MamK in Magnetospirillum magneticum AMB-1 might be somehow concerned with the widely accepted chemotaxis mechanism in bacteria.

Reversible watermarking based on invariant image classification and dynamical error histogram shifting

In this article, we present a novel reversible watermarking scheme. Its originality stands in identifying parts of the image that can be watermarked additively with the most adapted lossless modulation between: Pixel Histogram Shifting (PHS) or Dynamical Error Histogram Shifting (DEHS). This classification process makes use of a reference image derived from the image itself, a prediction of it, which has the property to be invariant to the watermark addition. In that way, watermark embedded and reader remain synchronized through this image of reference. DEHS is also an original contribution of this work. It shifts predict-errors between the image and its reference image taking care of the local specificities of the image, thus dynamically. Conducted experiments, on different medical image test sets issued from different modalities and some natural images, show that our method can insert more data with lower distortion than the most recent and efficient methods of the literature.