Mode-selective optical packet switching in mode-division multiplexing networks.

A novel mode-selective optical packet switching, based on mode-multiplexers/demultiplexers and multi-port optical micro-electro-mechanical systems (MEMS) switches, has been proposed and experimentally demonstrated. The experimental demonstration was performed using the LP(01), LP(11a) and LP(11b) modes of a 30-km long mode-division multiplexed few-mode fiber link, utilizing 40 Gb/s, 16-QAM signals.

Lysyl oxidase secreted by tumour endothelial cells promotes angiogenesis and metastasis.

BACKGROUND: Molecules that are highly expressed in tumour endothelial cells (TECs) may be candidates for specifically targeting TECs. Using DNA microarray analysis, we found that the lysyl oxidase (LOX) gene was upregulated in TECs compared with its expression in normal endothelial cells (NECs). LOX is an enzyme that enhances invasion and metastasis of tumour cells. However, there are no reports on the function of LOX in isolated TECs. METHODS: TECs and NECs were isolated to investigate LOX function in TECs. LOX inhibition of in vivo tumour growth was also assessed using ß-aminopropionitrile (BAPN). RESULTS: LOX expression was higher in TECs than in NECs. LOX knockdown inhibited cell migration and tube formation by TECs, which was associated with decreased phosphorylation of focal adhesion kinase (Tyr 397). Immunostaining showed high LOX expression in human tumour vessels in vivo. Tumour angiogenesis and micrometastasis were inhibited by BAPN in an in vivo tumour model. CONCLUSION: LOX may be a TEC marker and a possible therapeutic target for novel antiangiogenic therapy.

Biglycan is a specific marker and an autocrine angiogenic factor of tumour endothelial cells.

BACKGROUND: We isolated tumour endothelial cells (TECs), demonstrated their abnormalities, compared gene expression profiles of TECs and normal endothelial cells (NECs) by microarray analysis and identified several genes upregulated in TECs. We focused on the gene encoding biglycan, a small leucine-rich repeat proteoglycan. No report is available on biglycan expression or function in TECs. METHODS: The NEC and TEC were isolated. We investigated the biglycan expression and function in TECs. Western blotting analysis of biglycan was performed on sera from cancer patients. RESULTS: Biglycan expression levels were higher in TECs than in NECs. Biglycan knockdown inhibited cell migration and caused morphological changes in TECs. Furthermore, immunostaining revealed strong biglycan expression in vivo in human tumour vessels, as in mouse TECs. Biglycan was detected in the sera of cancer patients but was hardly detected in those of healthy volunteers. CONCLUSION: These findings suggested that biglycan is a novel TEC marker and a target for anti-angiogenic therapy.

Ultra-broad band, low power, highly efficient coherent wavelength conversion in quantum dot SOA.

We report broadband, all-optical wavelength conversion over 100 nm span, in full S- and C-band, with positive conversion efficiency with low optical input power exploiting dual pump Four-Wave-Mixing in a Quantum Dot Semiconductor Optical Amplifier (QD-SOA). We also demonstrate by Error Vector Magnitude analysis the full transparency of the conversion scheme for coherent modulation formats (QPSK, 8-PSK, 16-QAM, OFDM-16QAM) in the whole C-band.

Risk for interspecies transmission of zoonotic pathogens during poultry processing and pork production in Peru: A qualitative study.

Interspecies transmission of pathogens is an unfrequent but naturally occurring event and human activities may favour opportunities not previously reported. Reassortment of zoonotic pathogens like influenza A virus can result from these activities. Recently, swine and birds have played a central role as "mixing vessels" for epidemic and pandemic events related to strains like H1N1 and H5N1. Unsafe practices in poultry markets and swine farms can lead to interspecies transmission, favouring the emergence of novel strains. Thus, understanding practices that lead to interspecies interactions is crucial. This qualitative study aimed to evaluate poultry processing practices in formal and informal markets and the use of leftovers by swine farmers in three Peruvian cities: Lima (capital), Tumbes (coastal) and Tarapoto (jungle). We conducted 80 direct observations at formal and informal markets and interviewed 15 swine farmers. Processors slaughter and pluck chickens and vendors and/or processors eviscerate chickens. Food safety and hygiene practices were suboptimal or absent, although some heterogeneity was observed between cities and chicken vendors versus processors. Both vendors (76%) and processors (100%) sold the chicken viscera leftovers to swine farmers, representing the main source of chicken viscera for swine farms (53%). Swine farmers fed the chicken viscera to their swine. Chicken viscera cooking times varied widely and were insufficient in some cases. Non-abattoired poultry leads to the sale of poultry leftovers to small-scale swine farms, resulting in indirect but frequent interspecies contacts that can lead to interspecies transmission of bacterial pathogens or the reassortment of influenza A viruses. These interactions are exacerbated by suboptimal safety and hygiene conditions. People involved in these activities constitute an at-risk population who could play a central role in preventing the transmission of pathogens between species. Educational interventions on hygiene and food safety practices will be important for reducing the risk of interspecies influenza transmission.

A serpin with M(r) 43,000 is a binding protein of M(r) 25,000 protein, a substrate for protein ser/thr kinase detected in Xenopus laevis oocytes.

In an attempt to get some clue as to the function of M(r) 25,000 protein, a protein Ser/Thr kinase substrate detected in Xenopus laevis oocytes [Hashimoto, E. et al. (1995) J. Biochem. 118, 453-460], the binding protein was surveyed using the (32)P-labeled protein by casein kinase II as a screening probe. When the cytosolic proteins from oocytes were transferred to a polyvinylidene fluoride membrane and incubated with the labeled protein, only one protein with M(r) 43,000 was visualized on autoradiography. This protein was purified to a nearly homogeneous state through several column chromatography steps. The amino acid sequence of the amino-terminal region of this protein identified it as a kind of serine protease inhibitor (serpin) [Holland, L.J. et al. (1992) J. Biol. Chem. 267, 7053-7059]. However, the M(r) 25,000 protein did not have any effect on the inhibitory action of this serpin on alpha-chymotrypsin. In addition, several binding proteins were also detected in the particulate fraction of oocytes, although the exact identity of these proteins is not clear at this time. These results suggest that the M(r) 25,000 protein may play some role(s) by interacting with these binding proteins in Xenopus oocytes.

Soil phosphorus fractionation and phosphorus-use efficiencies of tropical rainforests along altitudinal gradients of Mount Kinabalu, Borneo.

We studied soil phosphorus (P) fractionation and P-use efficiencies (PUEs) of rainforests along altitudinal gradients (700-3100 m) on two types of parental rocks (sedimentary versus ultrabasic) on Mount Kinabalu, Borneo. Sedimentary rocks were known to contain more quartz (which does not adsorb P) than ultrabasic rocks. The pool (top 30 cm) of total P was always greater on sedimentary (ranging from 34.9 to 72.6 g m-2) than on ultrabasic (9.0-29.2 g m-2) rocks at comparable altitudes. Accordingly, the pools of organic P and labile inorganic P were always greater on sedimentary than on ultrabasic rocks. The pool of primary mineral, calcium P increased upslope from 1.7 to 4.3 g m-2 on sedimentary rock, suggesting that the altitudinal sequence of the sites reflected a decreasing magnitude of soil weathering upslope. The pool of calcium P on ultrabasic rock did not vary consistently with altitude (1.2-2.8 g m-2), probably reflecting the greater between-site variability of primary mineral P in parent rocks. When all sites were compared, the pool of most labile, bicarbonate-extracted inorganic P increased (ranging from 0.02 to 1.85 g m-2) with increasing calcium P. Calcium P was therefore considered to be an important P source to the biota on Kinabalu. Gross patterns in the variation of PUE (indexed as the reciprocal of the P concentration in litter) were best explained by the pool size of actively cycling P (total P minus occluded inorganic P). PUE, however, demonstrated distinct altitudinal patterns to generate an intricate conrol of P use pattern by soil P pools and altitude.

Relationships between the slope of the oxygen equilibrium curve and the cooperativity of hemoglobin as analyzed using a normalized oxygen pressure scale.

The oxygen equilibrium curve (OEC) for hemoglobin, which is usually expressed as a S vs. P plot, was expressed by normalizing P by Pdmax, where S is oxygen saturation, P is partial pressure of oxygen, and Pdmax is P at which the slope of the usual OEC is maximized. The maximal slope of normalized OEC gives Pdmax.S'max, where S'max is the maximal slope of the usual OEC, a measure for the oxygen transport efficiency of hemoglobin. Here, the term "efficiency" is used in the sense that the oxygen release from hemoglobin becomes more sensitive to oxygen pressure changes as S'max becomes larger. An analysis using 38 sets of published oxygen equilibrium data for human adult hemoglobin under various experimental conditions showed that (a) expressing OEC by means of S vs. P/Pdmax or S vs. log P is advantageous for analyzing the slope of OEC compared to usual S vs. P plot and (b) while the OEC differs depending on experimental conditions, S'max varies in close linear correlation to nmax (the maximal slope of the Hill plot which measures oxygen binding cooperativity), and Pdmax.S'max is almost equal to nmax/4. Thus, the parameter expressing oxygen transport efficiency is closely related to the parameter expressing oxygen binding cooperativity.

Intermittent nitrate therapy for prior myocardial infaraction does not induce rebound angina nor reduce cardiac events.

OBJECTIVE: Long-term nitrate therapy for ischemic heart disease may cause drug tolerance which diminishes its beneficial effects; consequently, intermittent administration of nitrates is recommended. With this regimen, however, the potential occurrence of rebound angina during the nitrate-free intervals is a source of concern. SUBJECTS AND METHODS: We carried out a retrospective study of 606 patients to determine whether rebound angina occurred when conventional continuous nitrate administration was replaced by intermittent administration as part of a long-term therapy protocol for prior myocardial infarction. The subjects were receiving treatment for myocardial infarction and included 293 patients treated with nitrates (Nitrate group) and 313 patients who were not (No-nitrate group). The former included 186 patients who received intermittent nitrate administration (Intermittent group) and 107 patients who received continuous administration (Continuous group). The mean period of observation was 4.3 +/- 1.6 months. RESULTS: There were no cases of rebound angina in the Intermittent group. Cardiac events occurred in one case in the No-nitrate group (0.3%), in 4 cases in the Continuous group (3.7%) and in 2 cases in the Intermittent group (1.1%). The incidence of cardiac events was thus significantly increased in the Continuous group compared to the No-nitrate group (p < 0.05; odds ratio 9.06; 95% CI 1.41-58.28). The Intermittent group did not significantly differ from the No-nitrate group in the incidence of cardiac events. CONCLUSION: It is concluded that intermittent administration of nitrates does not cause rebound angina and is therefore safe. A randomized controlled trial is needed to find the long-term effect on cardiac events.

[Survey of pesticide residues in baby foods (1996.4-1998.6)].

Between April 1996 to June 1998, 133 samples of 9 food commodities were analyzed for pesticide residues. In 8 samples of 5 commodities, 5 kinds of pesticides residues were detected. The baby foods in which the pesticides were detected were produced from vegetables and fruits. In our investigations, pesticide residues have been frequently detected in the raw materials. For the baby foods containing pesticides, intake amounts of the pesticides calculated from the daily feeding volume and the ADI were compared. Residual pesticide levels in baby food commodities are low, and it was concluded that they are not likely to present any problem in normal usage.

High-throughput optical image crossbar switch that uses a point light source array.

A high-throughput optical image crossbar switch (OPIX) that uses a point light source array as the switching device is constructed. A prototype OPIX is used to create various switching patterns for two-dimensional images. The newly constructed OPIX is suitable for high-speed operation because it uses point light sources instead of an optical shutter array as the switching device. Since it is based on an imaging system, the OPIX has a large space-bandwidth product. The introduction of OPIX to optical image data buses of parallel optical processing systems is particularly significant.

No induction of interchromosomal effect in male meiosis of Chinese hamsters with reciprocal translocations.

Chinese hamsters from five strains with reciprocal translocations, T(1;3)7Idr, T(1;3)8Idr, T(1;2)9Idr, T(7;9)16Idr, and T(1;5)17Idr, and a karyotypically normal strain, CHS/Idr, were used to look for an interchromosomal effect by chromosomal analysis of meiotic cells and one-cell embryos. The frequencies of nondisjunction at first meiosis in five normal (+/+) males, calculated by doubling the number of hyperhaploid cells, ranged from 0.43% to 1.33%, and there was no significant difference in frequency among individuals. On the other hand, the frequency of hyperhaploid cells in males heterozygous for each translocation ranged from 3.0% to 11.8%, and the frequency of hyperhaploid cells with an extra translocation-unrelated chromosome ranged from 0.2% to 0.4%, which is no different from that estimated from scoring of +/+ males at the second meiotic metaphase. In one-cell embryos from crosses between karyotypically normal females and male heterozygotes for T(1;2)9Idr and T(7;9)16Idr, 1.1% and 0.5% of embryos had an extra translocation-unrelated chromosome. Compared with the control, the frequency of meiotic nondisjunction showed no increase in male heterozygotes for the reciprocal translocations. Therefore, the results suggest that multivalents and rearranged chromosomes existing at first and second meiosis in male Chinese hamsters exert no influence on segregation of normal bivalents and chromosomes unrelated to the rearrangements.

Real-time holographic storage of a temporal bit sequence by using angular multiple recording of spectral components.

A novel method for storing a temporal bit sequence based on the angular multiple holographic recording of optical spectral components is proposed. In a preliminary experiment, a 4-bit-long nonreturn-to-zero 200-Mbit/s sequence is successfully recorded and regenerated from a photorefractive BaTiO(3) crystal.

Image logic algebra and its optical implementations.

A generic language for optical parallel processing image logic algebra (ILA), is proposed. In ILA a neighborhood configuration pattern (NCP) is introduced, and image transformations are defined by the use of NCP operations. The comprehensive relationship of ILA to symbolic substitution, optical array logic, mathematical morphology, and binary image algebra are clarified. Furthermore, an architecture that is suited for ILA and its optical implementations is proposed.

Applications of image-logic algebra: wire routing and numerical data processings.

Image logic algebra (ILA) is a comprehensive language for single-instruction stream multidata stream-type parallel processing, particularly for processing that is based on pattern matching. To demonstrate the usefulness of ILA for application to the computer-aided design of very-large-scale-integrated circuits, we describe a mostly parallel wire-routing algorithm based on Lee's maze algorithm by using ILA; our computer simulation verifies its validity. Another application to numerical data processing algorithms (including addition and multiplication) that is based on Booth's algorithm is also described by using ILA. Furthermore, the computational complexity of the proposed algorithms is evaluated.

Design considerations of the optical image crossbar switch.

Novel types of an optical image crossbar switch based on multiple imaging systems are proposed and demonstrated. The optical systems are based on gometric optics; accordingly, the systems have a large space bandwidth 20 x 20 switching for images with 10(3) x 10(3) pixels is realizable with the proposed optical image crossbar switches. A preliminary experiment is conducted for one of the proposed configurations. The possibility of incorporating the proposed optical switching system into optical parallel processing systems is particularly significant.