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We are developing a 1x8 single mode (SM) optical interface to facilitate the adoption of dense wavelength division multiplexing (DWDM) silicon photonic (SiPh) optical interconnects in exascale computing systems. A common method for fiber attachment to SiPh transceivers is ‘pigtailing’- the permanent adhesive bonding of fiber/v-groove arrays to onchip grating couplers (GC). This approach precludes standard high throughput surface mounting and solder reflow assembly of the transceiver onto system printed circuit boards. Our approach replaces the fixed pigtail with a low profile, small form factor, detachable expanded beam optical connector which consists of four essential parts: a GC array, a surface mount glass microlens array chip, an injection molded solder reflowable optical socket, and an injection molded SM light turn ferrule. The optical socket and ferrule are supplied by US Conec Ltd. To design the GC, we developed an optical simulator that considers CMOS foundry constraints in the optimization process. On-wafer measurements of the GC coupling loss to SMF28 fiber at 1310nm is ~1.4dB with a 1dB bandwidth of ~22nm. This ensures a wide low loss spectral window for at least 16 DWDM channels. The geometry of the optical system is arranged so that only a simple spherical lens is required for efficient mode matching in the expanded beam space. The fiber to fiber insertion loss through the light turn ferrule, two microlenses and GCs, and a looped back SOI waveguide ranged from 4.1-6.3dB, with insertion loss repeatability of 0.2dB after multiple mating cycles.

Tb/s class, copackaged coarse wavelength division multiplexing optical engine based on four wavelength vertical cavity surface emitting lasers (VCSELs) around 1 $\mu$ m is presented. The capability to scale bandwidth of 64 Gb/s using equalization and advanced modulation scheme, e.g., four-level pulse amplitude modulation (PAM4) is demonstrated. The capability to scale link distance of 2 km using single-mode VCSELs and standard SMF-28 fiber is demonstrated. Single-mode VCSELs error-free transmission at 25 Gb/s NRZ over 2 km of SMF-28 is achieved. Using forward-error-correction error-free transmission is possible for the PAM4 modulation over 2 km of SMF-28.

Postprandial hypertriglyceridaemia, defined as an increase in plasma triglyceride-containing lipoproteins following a fat meal, is a potential risk predictor of atherosclerotic cardiovascular disease and other chronic diseases. Several non-modifiable factors (genetics, age, sex and menopausal status) and lifestyle factors (diet, physical activity, smoking status, obesity, alcohol and medication use) may influence postprandial hypertriglyceridaemia. This narrative review considers the studies published over the last decade that evaluated postprandial hypertriglyceridaemia. Additionally, the genetic determinants of postprandial plasma triglyceride levels, the types of meals for studying postprandial triglyceride response, and underlying conditions (e.g. familial dyslipidaemias, diabetes mellitus, metabolic syndrome, non-alcoholic fatty liver and chronic kidney disease) that are associated with postprandial hypertriglyceridaemia are reviewed; therapeutic aspects are also considered.

Residual vascular risk exists despite the aggressive lowering of Low-Density Lipoprotein Cholesterol (LDL-C). A contributor to this residual risk may be elevated fasting, or non-fasting, levels of Triglyceride (TG)-rich lipoproteins. Therefore, there is a need to establish whethe a standardised Oral Fat Tolerance Test (OFTT) can improve atherosclerotic Cardiovascular (CV) Disease (ASCVD) risk prediction in addition to a fasting or non-fasting lipid profile.:An expert panel considered the role of postprandial hypertriglyceridaemia (as represented by an OFTT) in predicting ASCVD. The panel updated its 2011 statement by considering new studies and various patient categories. The recommendations are based on expert opinion since no strict endpoint trials have been performed.:Individuals with fasting TG concentration 2.5 mmol/L (220 mg/dL).:Postprandial hypertriglyceridaemia is an emerging factor that may contribute to residual CV risk. This possibility requires further research. A standardised OFTT will allow comparisons between investigational studies. We acknowledge that the OFTT will be mainly used for research to further clarify the role of TG in relation to CV risk. For routine practice, there is a considerable support for the use of a single non-fasting sample.

The goal of this systematic review is to synthesize the published meta-analyses assessing the role of nutritional, behavioral and physical activity factors/interventions on the prevention or treatment of pediatric and adolescent obesity. An online search was conducted in PubMed (end-of-search: September 30, 2015); English-language meta-analyses pooling observational and/or interventional studies examining weight-related indices on children and adolescents were included. Sixty-six meta-analyses corresponding to more than 900,000 children and adolescents were retrieved. The majority of meta-analyses included interventional studies most of which referred to mixed or combined interventions, including components such as diet, physical activity and sedentary behavior reduction. Discrepancies between meta-analyses on observational and interventional studies were noted. Combined interventions including physical activity and nutritional modifications seemed to represent the most effective means for tackling childhood obesity. Synthesis of interventional or observational evidence may yield discrepant results. The combination of enhanced physical activity and improved nutrition emerged as a promising intervention in the fight against childhood/adolescent obesity. However, further research is needed about the most effective multidimensional prevention strategy.

The need for additional IO bandwidth for data center device interconnection is well established. Optical interconnects can deliver required bandwidth along with energy and space efficiency at a cost that encourages adoption. To this end, we are developing an optical transceiver incorporating multimode VCSEL emitters in a coarse wavelength division multiplex (CWDM) system capable of transmission at 25Gbps per channel, 100Gbps/fiber, and a maximum aggregate bidirectional data rate of 1.2Tbps. Electrical connection to the transceiver can be made by solder reflow or LGA connector, and optical connection is made by means of a custom optical connector supporting CWDM transmission.

Tb/s class, co-packaged CWDM optical engine based on 4 wavelength VCSELs around 1μm is presented. The capability to scale bandwidth and link distance > 2km using single mode VCSELs and standard SMF28 fiber is demonstrated.

During the last decades survival has significantly improved and centenarians are becoming a fast-growing group of the population. Human life span is mainly dependent on environmental and genetic factors. Favourable modifications of lifestyle factors (e.g. physical activity, diet and not smoking) and healthcare (e.g. effective vascular disease prevention) have also increased human life span. Genetic factors contribute to the variation of human life span by around 25%, which is believed to be more profound after 85 years of age. It is likely that multiple factors influence life span and we need answers to questions such as: 1) What does it take to reach 100?, 2) Do centenarians have better health during their lifespan compared with contemporaries who died at a younger age?, 3) Do centenarians have protective modifications of body composition, fat distribution and energy expenditure, maintain high physical and cognitive function, and sustained engagement in social and productive activities?, 4) Do centenarians have genes which contribute to longevity?, 5) Do centenarians benefit from epigenetic phenomena?, 6). Is it possible to influence the transgenerational epigenetic inheritance (epigenetic memory) which leads to longevity?, 7) Is the influence of nutrigenomics important for longevity?, 8) Do centenarians benefit more from drug treatment, particularly in primary prevention?, and, 9) Are there any potential goals for drug research? Many definitions of successful ageing have been proposed, but at present there is no consensus definition. Such definitions may need to differentiate between "Longevity Syndrome" and "Exceptional Longevity"

International audience; Background/Aim: Triglycerides (TGs) are measured in studies evaluating changes in non-fasting lipid profiles after a fat tolerance test (FTT); however, the optimal timing for TG measurements after the oral fat load is unclear. The aim of this study was to evaluate how non-fasting TG levels vary after an oral FTT in healthy subjects. Methods: This meta-analysis included 113 studies with >5 participants of Caucasian race that were indexed in PubMed from its inception through March 2010, using the search term "postprandial lipemia". We only included studies that provided mean values and standard deviation (SD) (or standard error of the mean) for TG measurements at baseline (=fasting) and for at least one other time-point. Exclusion criteria included uncommon sampling time-points after the FTT, baseline TGs >= 2.0 mmol/L (>= 177mg/dl), and a body mass index >= 30kg/m(2). Results: All studies combined, weighted mean +/- SD TG values in mmol/L were 1.25 +/- 0.32 fasting, 1.82 +/- 0.40 at 2 h, 2.31 +/- 0.62 at 4 h, 1.87 +/- 0.63 at 6 h, and 1.69 +/- 0.80 at 8 h. After stratifying studies based on fat quantity in the test meal (= 40-= 50-= 70-= 80-= 90-= 100-= 110-120, >= 120 g), the highest standardized mean difference in TG levels from fasting levels was found in those having an oral fat load of >= 70 g and

A low cost Tb/s class CWDM optical engine prototype based on four different wavelength VCSELs around 1um is presented. 100Gbps operation per fiber is demonstrated.

The Multiwavelength Assemblies for Ubiquitous Interconnects (MAUI) program is a collaboration between Agilent Laboratories, Palo Alto, CA, and the University of Southern California, Los Angeles, with the goal of enabling fiber-to-the-processor by developing very-high-density optical interconnects and complementary metal-oxide-semiconductor (CMOS) interface electronics. This paper focuses on the parallel wavelength-division-multiplexed optical interconnect technologies and their potential impact on computer systems.

The electrooptic effect in lithium niobate crystals (LiNbO3) for extremely high externally applied electric fields of up to 65 kV/mm is investigated. Homogeneous electrooptic refractive-index changes of up to 4.8×10-3 are found for ordinarily polarized light. No quadratic electrooptic effect is observed. An upper bound for the quadratic electrooptic coefficient of |s13|≤2.3×10-21 m2/V2 is determined. Electrooptic, angular, and wavelength tuning of the Bragg condition of a thermally fixed hologram are demonstrated.

We present experimental data showing a significant dependence of light absorption on temperature in photorefractive LiNbO3:Fe crystals. The results are successfully explained by assuming that the widths of the Fe2+ absorption bands in the visible and in the infrared spectral region depend on temperature. The findings are of relevance for thermal fixing of holograms. Furthermore, a temperature-induced increase of the infrared absorption is promising for improved infrared recording. (C) 2002 American Institute of Physics.

In May 2012, a group of scientists and clinicians met in Athens (Greece) to consider the relevance of ageing, longevity, exceptional longevity and related genetic and non genetic markers. During this meeting, we firstly reviewed recent epidemiological and clinical studies on ageing, longevity and exceptional longevity, briefly analysed the ageing theories and discussed successful and unsuccessful ageing also taking into account the evolutionary perspective. Secondly, we considered the three phenotypes based on the definition of ageing, longevity and exceptional longevity and the associated biomarkers. Third, we discussed proposed treatments suitable to counteract or slow down ageing. Finally, this panel produced a consensus statement to highlight the importance of ageing, longevity and exceptional longevity, since this is a rapidly increasing phenotype worldwide. We acknowledge that not all experts in this field may completely agree with this statement.

In this letter, we demonstrate error-free operation of a 12-fiber /spl times/4-wavelength /spl times/5.21-Gb/s parallel-wavelength-division-multiplexed (PWDM) optical link. The 250-Gb/s transmitter and receiver assemblies each have a 5/spl times/8-mm footprint and consume a combined power of 1.5 W. To our knowledge, this is the first publication of a fully functional PWDM optical interconnect as well as the highest demonstrated bandwidth per unit area and bandwidth per unit power consumption for any multiple-channel fiber-optic interconnect. This technology is intended for short-distance high-bandwidth-density applications such as multiprocessor computer backplanes.

The Mediterranean diet (Mediet) is an eating pattern characterizing a lifestyle and culture that has been reported to contribute to better health and quality of life. The Mediet reflects food patterns typical of Mediterranean regions, where olive oil plays an essential role in the food pyramid. Olive oil is located in the middle and it is considered the principal source of dietary fat because of its high nutritional quality (particularly extra virgin olive oil). Several studies have shown the effect of the Mediet on healthy status by lowering the rates of coronary heart disease, certain cancers, and some other age-related chronic diseases. Although the scientific literature regarding diet and life span is complex and with different opinions, there are studies that demonstrate the beneficial effects of the Mediet on longevity. Therefore, the Mediet may be considered as including several nutraceuticals that favourably influence health. In the present review we discuss two Mediterranean populations from the island of Ikaria (Greece) and the Sicani Mounts (Sicily, Italy) whose longevity is attributed to a close adherence to the Mediet.

International audience; An Expert Panel group of scientists and clinicians met to consider several aspects related to non-fasting and postprandial triglycerides (TGs) and their role as risk factors for cardiovascular disease (CVD). In this context, we review recent epidemiological studies relevant to elevated non-fasting TGs as a risk factor for CVD and provide a suggested classification of non-fasting TG concentration. Secondly, we sought to describe methodologies to evaluate postprandial TG using a fat tolerance test (FTT) in the clinic. Thirdly, we discuss the role of non-fasting lipids in the treatment of postprandial hyperlipemia. Finally, we provide a series of clinical recommendations relating to non-fasting TGs based on the consensus of the Expert Panel: 1). Elevated non-fasting TGs are a risk factor for CVD. 2). The desirable non-fasting TG concentration is

At the present time, there is no widely agreed definition of postprandial lipaemia (PPL). This lack of a shared definition limits the identification and treatment of patients with exaggerated PPL as well as the evaluation of potential therapeutic agents. PPL is a complex syndrome characterized by non-fasting hypertriglyceridaemia that is associated with an increased risk of vascular events. This review considers the definition of PPL and the methodology for assessing this process.

The use of multi-wavelength light emitting diodes to generate predominantly white light for illumination has increased dramatically over the past years. Due to the nonlinear and often unpredictable relation between current and light output (i.e. efficiency) of LED's, direct feedback control using the actual optical intensity of each LED set has to be used to adjust and maintain the desired color points. While control of three-color systems (RGB) for display backlights has been shown, here we describe the control of a four color system (RGB+Amber) with a three channel sensor.

The direct integration of dense 48-channel parallel multiwavelength optical transmitter and receiver subassemblies directly onto a first level package using a flex lead attach has been demonstrated. Such an approach, at 10 Gb/s/channel would provide a linear edge bandwidth density of 300 Gb/s/cm. By attaching dense multichannel optical subassemblies directly onto an MCM, the performance limitations of the connectors and node card wiring can be avoided and the total bandwidth off the MCM can be increased while also enabling longer distance and higher speed signaling. This approach involves only a modest modification to the bent-flex approach commonly used for parallel optical modules intended for board mounting but enables a significant density and performance improvement for this application.

Adiponectin is a protein secreted exclusively by white adipose tissues and is abundantly present in human plasma. Adiponectin was found decreased in obese and diabetes mellitus type 2 patients and increased with weight reduction. A negative correlation between circulating adiponectin levels and body mass index and insulin resistance has been demonstrated. Plasma adiponectin concentrations were found lower in diabetes mellitus type 2 patients with coronary artery disease. Moreover, studies in aortic endothelial cells revealed that the protein exerts a dose-dependent decrease of the surface expression of vascular adhesion molecules and cytokine production from macrophages, suggesting the implication of adiponectin in atherosclerosis and inflammation. Weight loss and treatment with thiazolidinediones stimulate endogenous adiponectin production. Peripheral administration of adiponectin leads to reduction of visceral adiposity and increase of free fatty acid oxidation and insulin resistance. Furthermore, it enhances the expression of uncoupling proteins and sympathetic nerve activity in adipose tissues. Experimental studies in mice have shown that intraperitoneal administration of adiponectin lowers plasma glucose. These data show adiponectin to be an important factor in the issue of obesity and its associated disorders, and indicate a potential future utilization of adiponectin as a drug in the treatment of metabolic syndrome.

This article presents a promising approach for multi-Tb/s optical interconnects. This approach is contained in the MAUI project, which develops a parallel multiwavelength optical subassembly (PMOSA) that uses PWDM to gain the component-density advantages of two-dimensional parallel optics and the connector and cabling density advantages of CWDM. In the MAUI approach, a standard multimode 12-fiber ribbon is used with 4 wavelengths transmitted through each fiber, for a total of 48 optical channels.

This paper describes a 3 W 500-Gbps (4x12x10.42-Gb/s) parallel wavelength-division multiplexed optical interconnect that uses a 12-fiber ribbon with 4 wavelengths per fiber. The transmitter and receiver are each 5mm x 8 mm chip-scale packages.

This paper describes a 500-Gbps parallel wavelength-division multiplexed (PWDM) optical interconnect where 48 channels of 10.42-Gbps data are transmitted over a parallel 12-fiber ribbon with 4 wavelengths per fiber. The transmitter and receiver are each chip-scale packages with a footprint of 5 mm times 8 mm and a combined power consumption of 3 W. This work is motivated by the continually increasing bandwidth needs of short-distance computer processor interconnects, which are demanding optical solutions that maximize bandwidth per unit area, power consumption, and cost

We discuss a 12-fiber /spl times/ 4-wavelength /spl times/ 10.4-Gbit/s short-distance parallel-wavelength-division-multiplexed optical interconnect. The 0.5-Tbit/s transmitter and receiver assemblies each have a 5 /spl times/ 8-mm footprint and together consume 2.95 W.

This work presents the first fully-functional 48-channel parallel-wavelength-division-multiplexed (PWDM) transmitter, receiver and link results at a per-channel data rate of 5.21-Gb/s. This high-density PWDM optical interconnect gives an aggregate link bandwidth of a quarter terabit per second.

This report presents the results of research in the use of holographic modules in optoelectronic systems, their applications, and the characterization of polymer materials on which to record volume holograms for these modules. The first chapter makes the case that a direct interface between an optical memory and a chip integrating detectors and logic circuitry can better utilize the high parallelism inherent in holographic modules. Introduced also is the idea of reconfigurable computing and Field Programmable Gate Arrays (FPGAs) as the framework in which to design a hybrid system, the Optically Programmable Gate Array (OPGA), that outperforms its electronic counterpart by reducing its reconfiguration time by three orders of magnitude. The OPGA is the combination of three elements: an addressing device to selectively recall holographic data pages, an optical memory, and an optoelectronic chip. We also present a system that uses holograms to extract spatial and color information (4-D imaging) of a specimen and project it on to a 2-D space on the detector. By multiplexing several holograms many depth slices and color bands can be sent in parallel, making unnecessary the use of sophisticated and time-consuming scanning schemes.

This letter presents the theory and experimental results of an athermal holographic filter design employing a thermally actuated microelectromechanical system mirror to compensate for the drift of Bragg wavelength due to changes of temperature. The center wavelength of our holographic filter is shown to remain constant from 21/spl deg/C to 60/spl deg/C.

In this paper we report on a holographic method used to record fast events in the nanosecond time scale. Several frames of the expansion of shock waves in air and in a polymer sample are recorded holographically in a single shot experiment, using a pulse train generated with a single pulse from a Q-switched Nd:YAG laser. The time resolution is limited by the laser pulse width, which is 5.9 ns. The different frames are recorded on the holographic material using angle multiplexing. Two cavities are used to generate the signal and reference pulses at different angles. We also present a method in which the recording material is replaced by a CCD camera. In this method the holograms are recorded directly on the CCD and digitally reconstructed. The holograms are recorded on a single frame of the CCD camera and then digitally separated and reconstructed.

Whether the evaluation of body composition in obese people using low-cost, simple bedside, two-compartment techniques reflects the data obtained by indirect methods such as dual x-ray absorptiometry (DEXA) remains controversial. The aim of this study was to compare the data obtained by three methods of assessment of body composition (DEXA; bioelectrical impedance, BIA; and near infrared interactance, NII).Data on body composition obtained in 53 obese women by these three methods were compared, using the Bland and Altman procedure to test the relative validity.Although the correlation coefficients between DEXA and the two other methods were high, there were some major differences (limits of agreement) between data concerning fat and lean mass.The present study indicates that these methods cannot be considered as interchangeable and raises some questions on the use of BIA and NII as a single method of evaluation of body composition in clinical research and practice in obese populations.

The Optically Programmable Gate Array (OPGA), an optical version of a conventional FPGA, benefits from a direct parallel interface between an optical memory and a logic circuit. The OPGA utilizes a holographic memory accessed by an array of VCSELs to program its logic. An active pixel sensor array incorporated into the OPGA chip makes it possible to optically address the logic in a very short time allowing for rapid dynamic reconfiguration. Combining spatial and shift multiplexing to store the configuration pages in the memory, the OPGA module can be made compact. The reconfiguration capability of the OPGA can be applied to solve more efficiently problems in pattern recognition and database search.

The high data transfer rate achievable in page-oriented optical memories demands for parallel interfaces to logic circuits able to process efficiently the data. The Optically Programmable Gate Array, an enhanced version of a conventional FPGA, utilizes a holographic memory accessed by an array of VCSELs to program its logic. Combining spatial and shift multiplexing to store the configuration pages in the memory, the OPGA module is very compact and has extremely short configuration time allowing for dynamic reconfiguration. The reconfiguration capability of the OPGA can be applied to solve more efficiently problems in pattern recognition and digit classification.

Reconfigurable processors bring a new computational paradigm where the processor modifies its structure to suit a given application, rather than having to modify the application to fit the device. The Optically Programmable Gate Array, an enhanced version of a conventional FPGA, utilizes a holographic memory accessed by an array of VCSELs to program its logic. Combining spatial and shift multipexing to store the configuration pages in the memory, the OPGA module is very compact and has extremely short configuration time allowing for dynamic reconfiguration. The reconfiguration capability of the OPGA can be applied to solve more efficiently problems in pattern recognition and digit classification.

We have experimentally discovered that the Signal-to-Noise Ratio (SNR) of holograms initially remains constant as the number of holograms stored increases and drops significantly only after a large number of holograms are recorded. This suggests that in a large-scale memory, the limiting noise source is not crosstalk between holograms but holographic noise due to the prolonged exposure of the signal beam. We have carried out experiments to investigate the formation and influence of the inter-pixel grating noise and shown that it is a very important form of holographic noise. We also proposed and demonstrated the use of random-phase modulation in the signal to suppress the inter-pixel grating noise.

Summary form only given, as follows. Reconfigurable processors, like the Field Programmable Gate Arrays (FPGAs), open new computational paradigms where the processor is able to tailor its internal structure to better implement a given application. A typical FPGA consists of an array of configurable logic blocks and a mesh of interconnections fully programmable by the user to perform a given application. By just changing its internal connectivity, the FPGA can implement a totally different new function. However in most of the applications, the FPGA is configured only once and used as coprocessor to carry out some highly complex or time-consuming computation. The reason for such limitation is the small communication bandwidth between the FPGA chip and the external memory, usually ROM, where the configuration data is stored. The Optically Programmable Gate Array (OPGA), an enhanced version of a conventional. FPGA, can overcome this problem. The OPGA utilizes a holographic memory accessed by an array of VCSELs to program its logic. The on-chip logic has been complemented with an array of photodetectors to detect the configuration template recorded in the memory. Combining spatial and shift multiplexing to store the configuration pages in the memory, the OPGA module is very compact and has extremely short configuration time allowing for dynamic reconfiguration. The reconfiguration capability of the OPGA can be applied to solve more efficiently problems in pattern recognition and database searches.

We report on holographic recording of nanosecond events on a conventional CCD camera. Three frames of an air-discharge event, with resolution of 5.9 ns and frame interval of 12 ns, are recorded in a single CCD frame. Each individual frame is reconstructed by digital filtering of the CCD frame, since successively recorded holograms are centered at different carrier frequencies in the spatial frequency domain. (C) 2002 Optical Society of America.