Generating high-power Lissajous structured modes and trochoidal vortex beams by an off-axis end-pumped Nd:YVO4 laser with astigmatic transformation.

High-power structured beams with the transverse morphologies as the Lissajous figures are generated by an Nd:YVO4 laser under two-dimensional off-axis pumping. By fine-tuning the cavity length in the neighborhood around the condition of longitudinal-transverse coupling, different cases of accidental degeneracies from the intracavity astigmatism are achieved to lead the output emission to be various Lissajous modes with different transverse frequency ratios. The generated Lissajous modes reveals good power performance with slope efficiency up to 47% and optical-to-optical conversion efficiency to be higher than 37.5% at a pump power of 16 W. Moreover, by applying beam transformation via a single-lens astigmatic mode converter, the generated Lissajous modes are further converted into structured vortex beams with transverse patterns localized on the trochoidal curves. The transformed trochoidal vortex beams are confirmed to preserve well-defined mode structures even when the average output power has been scaled up to be higher than 4 W.

High-peak-power structured beams by an Nd:YAG/Cr4+:YAG laser in a near-hemispherical cavity.

An Nd:YAG/Cr4+:YAG passively Q-switched (PQS) laser in a near-hemispherical cavity is exploited to generate high-order structured pulsed fields. Under tightly focused on-axis pumping, radial-order Laguerre-Gaussian (LG) modes with controllable mode orders by the input pump power are realized to exhibit quite stable temporal behavior. The pulse repetition rates of radial-LG modes can reach up to 78 kHz with an average output power of 0.57 W and peak power beyond 300 W under a 5-W pump level. Furthermore, by introducing 1D off-axis pumping into the PQS laser, various structured pulsed fields with transverse morphologies as high-order Ince-Gaussian (IG) modes are further created. With clean and well-defined beam structures, the IG pulsed fields can be nicely reconstructed by the resonant modes of the inhomogeneous Helmholtz equation for spherical cavities. More importantly, these high-order PQS IG modes reveal highly regular pulse trains with the maximum pulse repetition rate beyond 20 kHz and overall peak power higher than 1.5 kW.

A scalable and continuous-upgradable optical wireless and wired convergent access network.

In this work, a scalable and continuous upgradable convergent optical access network is proposed. By using a multi-wavelength coherent comb source and a programmable waveshaper at the central office (CO), optical millimeter-wave (mm-wave) signals of different frequencies (from baseband to > 100 GHz) can be generated. Hence, it provides a scalable and continuous upgradable solution for end-user who needs 60 GHz wireless services now and > 100 GHz wireless services in the future. During the upgrade, user only needs to upgrade their optical networking unit (ONU). A programmable waveshaper is used to select the suitable optical tones with wavelength separation equals to the desired mm-wave frequency; while the CO remains intact. The centralized characteristics of the proposed system can easily add any new service and end-user. The centralized control of the wavelength makes the system more stable. Wired data rate of 17.45 Gb/s and w-band wireless data rate up to 3.36 Gb/s were demonstrated after transmission over 40 km of single-mode fiber (SMF).

Coding for stable transmission of W-band radio-over-fiber system using direct-beating of two independent lasers.

We demonstrate experimentally Manchester (MC) coding based W-band (75 - 110 GHz) radio-over-fiber (ROF) system to reduce the low-frequency-components (LFCs) signal distortion generated by two independent low-cost lasers using spectral shaping. Hence, a low-cost and higher performance W-band ROF system is achieved. In this system, direct-beating of two independent low-cost CW lasers without frequency tracking circuit (FTC) is used to generate the millimeter-wave. Approaches, such as delayed self-heterodyne interferometer and heterodyne beating are performed to characterize the optical-beating-interference sub-terahertz signal (OBIS). Furthermore, W-band ROF systems using MC coding and NRZ-OOK are compared and discussed.

Hyperfine splitting of the 2s1/2 and 2p1/2 levels in Li- and be-like ions of (59)(141) Pr.

High-resolution spectroscopy of the 2s(1/2)-2p(1/2) transition in the extreme ultraviolet region is shown to resolve the level splitting induced by the nuclear magnetic field of both the 2s(1/2) and the 2p(1/2) levels in lithiumlike (141)Pr(56+) and of the 2s(1/2)2p(1/2) (3)P(1) level in berylliumlike (141)Pr(55+). The (141)Pr ions are an ideal test of this measurement approach because their energy levels are known well from first principles and are unaffected by small energy contributions from QED and nuclear magnetization effects. The accuracy attained in the measured 196.5 ± 1.2 meV 2s(1/2) splitting is more than an order of magnitude better than that achieved before using crystal spectroscopy of the 2s(1/2)-2p(3/2) x-ray transition and at the level needed to implement a proposed scheme for disentangling the contributions from QED and nuclear magnetization effects in higher-Z ions, such as (209)Bi.

A multiply-add engine with monolithically integrated 3D memristor crossbar/CMOS hybrid circuit.

Silicon (Si) based complementary metal-oxide semiconductor (CMOS) technology has been the driving force of the information-technology revolution. However, scaling of CMOS technology as per Moore's law has reached a serious bottleneck. Among the emerging technologies memristive devices can be promising for both memory as well as computing applications. Hybrid CMOS/memristor circuits with CMOL (CMOS + "Molecular") architecture have been proposed to combine the extremely high density of the memristive devices with the robustness of CMOS technology, leading to terabit-scale memory and extremely efficient computing paradigm. In this work, we demonstrate a hybrid 3D CMOL circuit with 2 layers of memristive crossbars monolithically integrated on a pre-fabricated CMOS substrate. The integrated crossbars can be fully operated through the underlying CMOS circuitry. The memristive devices in both layers exhibit analog switching behavior with controlled tunability and stable multi-level operation. We perform dot-product operations with the 2D and 3D memristive crossbars to demonstrate the applicability of such 3D CMOL hybrid circuits as a multiply-add engine. To the best of our knowledge this is the first demonstration of a functional 3D CMOL hybrid circuit.

Corrigendum: A multiply-add engine with monolithically integrated 3D memristor crossbar/CMOS hybrid circuit.

This corrects the article DOI: 10.1038/srep42429.

Chorionic villi sampling: laboratory experience with 4,000 consecutive cases.

Experience with 4,000 consecutive CVS cases shows that 1) the combination of both the direct and culture methods greatly reduces false diagnoses and maternal cell contamination; 2) the time interval between the sampling procedure and processing of villus specimens influences the quality of direct preparations; 3) maternal cell contamination (MCC) can be minimized with dissection of CVS specimens. We have compiled a large volume of confined placental mosaicism (CPM) cases to serve as a resource in interpreting mosaic cytogenetic findings. It was noted that, in up to 92% of the mosaic cases, the abnormal cell line was confined to the placenta. The frequency of true chromosomal mosaicism was 0.2%, and is not different from that for amniocentesis.

The production and evaluation of contrast-carrying liposomes made with an automatic high-pressure system.

An automatic, high-pressure system (Microfluidizer) has been found useful for producing contrast-carrying liposomes on an industrial scale. The goal of this investigation was to determine the feasibility of using this new microemulsification process to manufacture contrast-carrying microemulsified liposomes (MELs). Seven contrast media (three ionic, four nonionic) were encapsulated into the MELs. Light and electron microscopy, light scattering, radioisotope, and CT scan techniques were used to characterize these MELs, and the contrast entrapments among the studied media were compared. The contrast-carrying MELs had good properties for imaging normal reticuloendothelial tissues, selectively. They had a narrow size range (0.1-3.0 micron), a single bilayer wall, high liver and spleen upake, and low leakage rates. The nonionic media were significantly more effectively entrapped in the MELs than the ionic media (P less than .05). The iodine-to-lipid weight ratio was about 1:16 for ionic media and 1:4 for nonionic media. Physical properties of the contrast media such as osmotic pressure and charge appeared to affect contrast entrapment. It was concluded that the microemulsification process is a useful system for producing contrast-carrying liposomes continuously, on a large scale and in a reproducible manner.

Biodistribution and radioimmunopharmacokinetics of 131I-Ama monoclonal antibody in atherosclerotic rabbits.

Monoclonal antibodies have been raised against Ama isolated from human and experimental atherosclerotic plaque. 131I-Ama-MoAb in the whole antibody form was injected into normal NZW rabbits and Watanabe hyperlipidemic rabbits. Biodistribution studies showed that atheromatous aortas had a significantly higher (5-7X) uptake of 131I-Ama-MoAb than that of normal aortas. However, 131I-Ama-MoAb was cleared very slowly from atherosclerotic rabbits. As a result, atheromas could not be identified by imaging because of the low target to non-target ratios.

Surface-assisted photoalignment in dye-doped liquid-crystal films.

This study examines the surface-assisted photoalignment effect of dye-doped liquid-crystal films having a homogeneous alignment. Observations made using a polarizing optical microscope, a scanning electronic microscope, and an atomic force microscope confirm that the morphology of laser-induced surface-adsorbed dyes at the command surface strongly affects the orientation of liquid crystals (LC's) in a manner that depends significantly on the intensity and duration of the pumping. In weak-intensity regime, a homogeneous and fine layer of adsorbed dyes competes with a layer of ripple structure in reorienting LC's. These two effects dominantly cause LC's to reorient perpendicular and parallel to the polarization direction of the pump beam in the early and late stages, respectively. In the high-intensity regime, rough and inhomogeneous ribbonlike adsorbents produced by rapid and random aggregation and adsorption form on the top of the preformed microgrooves, reorienting LC's irregularly. This surface morphology does not enable photoalignment.

Ultratag RBC kit for combined cardiac first-pass and multigated acquisition studies.

UNLABELLED: The authors developed a procedure to use the in vitro Ultratag (Mallinckrodt, St. Louis, MO) red blood cell (RBC) labeling kit for both first-pass (FP) and multigated acquisition (MUGA) studies with a high specific activity in a reduced volume (50 mCi/0.5 ml) and a high labeling efficiency that can be used with a single-crystal camera to yield a quality study. METHODS: A packed red blood cell (PRBC) bolus was created by two methods: (a) reducing the volume of the components of the Ultratag kit and (b) centrifuging the final dose volume. The labeling efficiency of each bolus was evaluated, each PRBC bolus was visually inspected for clots and percent hemolysis was assessed using a hemocytometer at 30 min, 1 hr and 2 hr postcentrifugation. RESULTS: Use of the first method, the 50% kit, provided the best results. However, the resulting volume from this kit only approached 1 ml, which is not clinically adequate for a first-pass study. In the second method, the total volume was centrifuged to form a PRBC bolus, which appeared to be stable in the syringe for at least 2 hr. A combined FP/MUGA study from a centrifuged 50% reduced kit was performed in one normal subject as a preliminary assessment of the clinical utility of this procedure. The image quality of the scan is diagnostically adequate. CONCLUSION: By using the in vitro Ultratag kit, a compact PRBC bolus was created that was stable in the syringe and could be reinjected safely into the patient for combined cardiac FP/MUGA studies.

RAPD analysis of Astragalus medicines marketed in Taiwan.

The genetic variability of Astragalus medicine materials sold by twenty randomly selected stores in Taiwan was investigated using RAPD analysis in order to obtain available primers which could clearly differentiate among them. Total DNA isolated from the rhizomes of the samples were used as templates, and sixty 10 mer arbitrary primers were used in the analysis. The aim of the present study is to construct an identification model of molecular biotechniques applicable to Chinese herbal medicines in RAPD analysis. Three of the primers, OPT-03, OPT-13, and OPT-17, revealed polymorphic RAPD fingerprints among the samples of Astragalus membranaceus, and between Astragalus membranaceus and Hedysarum polybotrys samples. SSCP analysis was also conducted on PCR products from the ITS-1 region of ribosomal DNA in order to differentiate the two species.

Innovative nuclear pharmacy service. A comprehensive management plan for clinical investigations.

OBJECTIVE: To provide an overview of the investigational nuclear pharmacy service at the Medical University of South Carolina. DATA SOURCES: References were selected from published bibliographies of nuclear pharmacy and hospital pharmacy articles and from specific-topic searches of the MEDLINE computerized database (all languages, through 1992). STUDY SELECTION: Studies of clinical pharmacy functions that were considered relevant to the specialty practice of nuclear pharmacy were chosen. DATA EXTRACTION: Studies were reviewed for internal consistency and appropriateness. DATA SYNTHESIS: Data on the clinical impact of nuclear pharmacy services do not exist. CONCLUSIONS: Based on our experience in establishing an investigational drug service, we conclude that nuclear pharmacists should take an active role in clinical investigations. The outcomes of this kind of involvement are very rewarding.

Thomson scattering in the average-atom approximation.

The average-atom model is applied to study Thomson scattering of x-rays from warm dense matter with emphasis on scattering by bound electrons. Parameters needed to evaluate the dynamic structure function (chemical potential, average ionic charge, free electron density, bound and continuum wave functions, and occupation numbers) are obtained from the average-atom model. The resulting analysis provides a relatively simple diagnostic for use in connection with x-ray scattering measurements. Applications are given to dense hydrogen, beryllium, aluminum, and titanium plasmas. In the case of titanium, bound states are predicted to modify the spectrum significantly.

TRPV4 mediates tumor-derived endothelial cell migration via arachidonic acid-activated actin remodeling.

Changes in intracellular calcium [Ca(2+)](i) levels control critical cytosolic and nuclear events that are involved in the initiation and progression of tumor angiogenesis in endothelial cells (ECs). Therefore, the mechanism(s) involved in agonist-induced Ca(2+)(i) signaling is a potentially important molecular target for controlling angiogenesis and tumor growth. Several studies have shown that blood vessels in tumors differ from normal vessels in their morphology, blood flow and permeability. We had previously reported a key role for arachidonic acid (AA)-mediated Ca(2+) entry in the initial stages of tumor angiogenesis in vitro. In this study we assessed the mechanism involved in AA-induced EC migration. We report that TRPV4, an AA-activated channel, is differentially expressed in EC derived from human breast carcinomas (BTEC) as compared with 'normal' EC (HMVEC). BTEC display a significant increase in TRPV4 expression, which was correlated with greater Ca(2+) entry, induced by AA or 4αPDD (a selective TRPV4 agonist) in the tumor-derived ECs. Wound-healing assays revealed a key role of TRPV4 in regulating cell migration of BTEC but not HMVEC. Knockdown of TRPV4 expression completely abolished AA-induced BTEC migration, suggesting that TRPV4 mediates the pro-angiogenic effects promoted by AA. Furthermore, pre-incubation of BTEC with AA induced actin remodeling and a subsequent increase in the surface expression of TRPV4. This was consistent with the increased plasma membrane localization of TRPV4 and higher AA-stimulated Ca(2+) entry in the migrating cells. Together, the data presented herein demonstrate that: (1) TRPV4 is differentially expressed in tumor-derived versus 'normal' EC; (2) TRPV4 has a critical role in the migration of tumor-derived but not 'normal' EC migration; and (3) AA induces actin remodeling in BTEC, resulting in a corresponding increase of TRPV4 expression in the plasma membrane. We suggest that the latter is critical for migration of EC and thus in promoting angiogenesis and tumor growth.

Antitumor and immunostimulating effects of Anoectochilus formosanus Hayata.

The water extract of Anoectochilus formosanus Hayata showed a potent tumor inhibitory activity in BALB/c mice after subcutaneous transplantation of CT-26 murine colon cancer cells. The tumor-inhibition ratios of mice pre-administered with A. formosanus for 2 days before tumor transplantation, and treated further for 12 consecutive days, were 55.4% and 58.9% at the oral dose of 50 and 10 mg/mouse per day, respectively. Even for the tumor-bearing mice, after oral administration of the water extract of A. formosanus for 12 consecutive days, the tumor inhibition ratios were still 23.8% and 40.5% at doses of 50 and 10 mg/mouse, respectively. Because the low-concentration water extract of A. formosanus does not show direct cytotoxicity in CT-26 tumor cells, we observed further that oral administration of the water extract of A. formosanus may activate murine immune responses, such as stimulating the proliferation of lymphoid tissues and activating the phagocytosis of peritoneal macrophages against Staphylococcus aureus. This study suggests that the antitumor activity of A. formosanus may be associated with its potent immunostimulating effect. It is worth further analyzing the immunomodulating component purified from A. formosanus, and evaluating its potential value for the treatment of human cancers.

Properties of a coaxial cw CO(2) laser.

A cw CO(2) laser has been developed in which the active medium is formed by a discharge between coaxial electrodes. The laser gain and saturation properties have been studied as functions of the various device parameters. Over-all efficiency is about the same as for a conventional longitudinal discharge laser, and advantages of the coaxial geometry include low voltage operation, rapid cooling, and rugged construction.

A study of the concept of non-radioactive unit-dosed reagent kits [cold unit doses (CUDs)] as an efficient and cost-saving method for 99mTc radiopharmaceutical preparation.

Traditionally, when preparing 99mTc-labeled radiopharmaceuticals, [99mTc]pertechnetate is added to the entire contents of a vial of reagent kit, and patient doses are subsequently withdrawn from the vial. This technique of compounding can be potentially wasteful for two reasons: (1) once reconstituted with 99mTc, most reagent kits have a relatively short shelf-life, and thus the entire contents may not be used before expiration and (2) due to a need to conserve radioactivity in many hospitals, enough [99mTc]pertechnetate is added to the reagent kit in order to retrieve only 1-2 patient doses, even though adequate chemicals (ligand, reducing agent, etc.) are present in the reagent kit to supply as many as 5-10 doses. Hence, a method for optimizing the efficient use of reagent kits would be desirable. The purpose of this study was to determine the feasibility of unit-dosing non-radioactive reagent kits and storing these cold unit doses (CUDs) for eventual labeling with 99mTc. To evaluate this concept, unit doses were prepared from reagent kits of medronate (MDP) and pentetate (DTPA). The specific variables studied in this research were the effects of storage time, storage temperature and reconstitution volume (dilution) on the unit doses. These effects were monitored by measuring the radiochemical and biodistribution properties of the unit doses following their final reconstitution with [99mTc]pertechnetate. The labeling efficiency was determined using instant thin layer chromatograph (ITLC), and the biodistribution patterns of these radiolabeled CUDs were studied in mice. The results showed the MDP- and DTPA-CUDs stored at -18 degrees C retained the properties which resulted in acceptable radiochemical purity and biodistribution in mice for as long as 30 days. On the other hand, the radiochemical purity of MDP and DTPA unit doses stored at 25 degrees C deteriorated rapidly. Mean radiochemical purities as low as 0.58-19.4% were observed on day 30. Altered biodistributions were observed in a manner consistent with the decreased labeling efficiencies. The CUDs of lower dilution (3 mL) appeared to be more stable than the CUDs of higher dilution (10 mL). However, the effect of reconstitution volume was much less significant than the temperature effect on the CUDs. In conclusion, the concept of unit-dosing non-radioactive reagent kits appears to provide an efficient and cost-saving method for preparing infrequent and emergency radiopharmaceutical doses. The study also showed that the storage temperature of these unit doses is critical to the success of the procedure. The volume of reconstitution has a minimal impact on the stability of CUDs if stored at the appropriate temperature.