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A hybrid silicon DFB laser array emitting over 200nm was integrated with EAMs (3dB bandwidth>30GHz). Four bandgaps spread over >100nm were realized using quantum well intermixing for increased spectral gain and for laser-modulator detuning.

Using a single epitaxial structure, multiple CW operational DFB lasers with backside photodetectors, emitting over a 200 nm range from 1250–1450 nm are integrated on silicon. Four bandgaps spread over >100 nm were realized using quantum well intermixing for increased spectral gain.

Reducing energy consumption in multi-processor systems-on-chip (MPSoCs) where communication happens via the network-on-chip (NoC) approach calls for multiple voltage/frequency island (VFI)-based designs. In turn, such multi-VFI architectures need efficient, robust, and accurate run-time control mechanisms that can exploit the workload characteristics in order to save power. Despite being tractable, the linear control models for power management cannot capture some important workload characteristics (e.g., fractality, non-stationarity) observed in heterogeneous NoCs, if ignored, such characteristics lead to inefficient communication and resources allocation, as well as high power dissipation in MPSoCs. To mitigate such limitations, we propose a new paradigm shift from power optimization based on linear models to control approaches based on fractal-state equations. As such, our approach is the first to propose a controller for fractal workloads with precise constraints on state and control variables and specific time bounds. Our results show that significant power savings (about 70%) can be achieved at run-time while running a variety of benchmark applications.

Managing cardiac disease and abnormal heart rate variability remain challenging problems with an enormous economic and psychological impact worldwide. Consequently, the purpose of this paper is to introduce a fractal approach to pacemaker design based on the constrained finite horizon optimal control problem. This is achieved by modeling the heart rate dynamics via fractional differential equations. Also, by using calculus of variations, we show that the constrained finite horizon optimal control problem can be reduced to solving a linear system. Finally, we discuss the hardware complexity involved in the practical implementation of fractal controllers.

Social networking has gained immense traction in many areas, including teaching and learning. Networking sites for teachers aim to facilitate teacher communication and information sharing, but fall short of their potential. In order to support more effective use of online resources and better communication among teachers, we develop a suite of new user modeling and recommendation capabilities within a middle school teacher networking site. We foster collaboration among novice and experienced teachers when they share similar interests, enabling new mentoring relationships, and promote the use of relevant educational resources. We illustrate our approach with an implemented system called PedConnect that analyzes user activities and presents intelligent suggestions for collaboration and resource use.

The present work reports the results of the study of the effect of metal contaminants on the oxidation, thermal, and storage stability of Jatropha curcas biodiesel (JCB) with and without antioxidants. Taking Pyrogallol (PY) as the most effective antioxidant based on the earlier work of the authors, JCB was mixed with different transition metals—Fe, Ni, Mn, Co, and Cu in different concentrations. Induction period (IP) was measured using Rancimat method (EN 14112). The ASTM D6468 and thermogravimetric analysis (TGA) methods are used for evaluating the thermal behavior of JCB. Based on results, several correlations are developed for assessing the oxidation, thermal, and storage stability. For the purpose of optimization, response surface methodology (RSM) is used. A comparison between the experimental values and those predicted by the correlation shows that all the data points lie within ±10% deviation lines of the experimental results. The optimized concentration of PY for 2 ppm metal-contaminated biodiesel to have an IP of 6 hr is 326.96, 361.64, 386.15, 417.24, and 600 ppm for Fe, Ni, Mn, Co, and Cu, respectively. From the experiments it is found that if metal concentration is 0, then, 200 ppm of PY is sufficient to make biodiesel stable for 6 months. If metal (Fe) concentration is 2 ppm or more, then 800 ppm PY is sufficient to make biodiesel stable for 5.5 months. This is the first study of its kind being reported in the literature in which RSM is used for design of experiment for developing the correlation for oxidation, thermal, and storage stability. The models developed by RSM will be highly useful for predicting the optimum antioxidant concentration to impart maximum fuel stability in JCB.

A hybrid silicon integrated broadband (60 nm) DFB array and high-speed modulator (50 Gbps) are presented, showing the potential of this technology for future transmitters in optical interconnects.

Naphthalene degrading bacterial consortium (DV-AL) was developed by enrichment culture technique from sediment collected from the Alang-Sosiya ship breaking yard, Gujarat, India. The 16S rRNA gene based molecular analyzes revealed that the bacterial consortium (DV-AL) consisted of four strains namely, Achromobacter sp. BAB239, Pseudomonas sp. DV-AL2, Enterobacter sp. BAB240 and Pseudomonas sp. BAB241. Consortium DV-AL was able to degrade 1000 ppm of naphthalene in Bushnell Haas medium (BHM) containing peptone (0.1%) as co-substrate with an initial pH of 8.0 at 37 °C under shaking conditions (150 rpm) within 24 h. Maximum growth rate and naphthalene degradation rate were found to be 0.0389 h −1 and 80 mg h −1 , respectively. Consortium DV-AL was able to utilize other aromatic and aliphatic hydrocarbons such as benzene, phenol, carbazole, petroleum oil, diesel fuel, and phenanthrene and 2-methyl naphthalene as sole carbon source. Consortium DV-AL was also efficient to degrade naphthalene in the presence of other pollutants such as petroleum hydrocarbons and heavy metals.

We demonstrate multiple bandgap integration on the hybrid silicon platform using quantum well intermixing. A broadband DFB laser array and a DFB-EAM array are realized on a single chip using four bandgaps defined by ion implantation enhanced disordering. The broadband laser array uses two bandgaps with 17 nm blue shift to compensate for gain roll-off while the integrated DFB-EAMs use the as-grown bandgap for optical gain and a 30 nm blue shifted bandgap for modulation. The multi-channel DFB array includes 13 lasers with >90 nm gain-bandwidth. The transponder includes four DFB-EAMs with 14 dB DC extinction at 4 V bias.

We have demonstrated a traveling-wave electroabsorption modulator based on the hybrid silicon platform. For a device with a 100 μm active segment, the small-signal electro/optical response renders a 3 dB bandwidth of around 42 GHz and its modulation efficiency reaches 23 GHz/V. A dynamic extinction ratio of 9.8 dB with a driving voltage swing of only 2 V was demonstrated at a transmission rate of 50 Gb/s. This represents a significant improvement for modulators compatible with integration of silicon-based photonic integrated circuits.

We present a quantum well intermixed hybrid silicon DFB laser array with gain-bandwidth >90nm. CW laser maximum output power is 4 mW/laser at 20 °C with maximum operating temperature of 60 °C

We demonstrate an integrated 1310 nm DFB-EAM transponder on the hybrid silicon platform using ion implantation induced quantum well intermixing. CW laser operation up to 60 °C is achieved along with 2 GHz modulator bandwidth.

The use of virtual keyboards is becoming ubiquitous with increasing use in mobile devices and touch-screens. Till now the research has mainly focused on developing layouts which support high typing speed, but the error aspect has been largely ignored. This research aims at developing a novel error model which relates accuracy with a given layout using the distance between keys. The main idea here is that the error model should predict the error rate by the layout specification alone.

We review III-V on silicon-on-insulator (SOI) heterogeneous integration for the demonstration of lasers, suitable for inter-chip and intra-chip optical interconnects. A low temperature oxygen plasma enhanced bonding technology is used to realize the III-V/SOI integration. The realization of silicon AWG lasers, quantum well intermixed DFB lasers and micro ring lasers on the III-V/SOI material platform is discussed.

The performance of Watson & Ahumada's model of human visual motion sensing is compared against human psychophysical performance. The stimulus consists of random dots undergoing rotary motion, displayed in a circular annulus. The model matches psychophysical observer performance with respect to most parameters. It is able to replicate some key psychophysical findings such as invariance of observer performance to dot density in the display, and decrease of observer performance with frame duration of the display.Associated with the concept of rotary motion is the notion of a center about which rotation occurs. One might think that for accurate estimation of rotary motion in the display, this center must be accurately known. A simple vector analysis reveals that this need not be the case. Numerical simulations confirm this result, and may explain the position invariance of MST(d) cells. Position invariance is the experimental finding that rotary motion sensitive cells are insensitive to where in their receptive field rotation occurs.When all the dots in the display are randomly drawn from a uniform distribution, illusory rotary motion is perceived. This case was investigated by Rose & Blake previously, who termed the illusory rotary motion the omega effect. Two important experimental findings are reported concerning this effect. First, although the display of random dots evokes perception of rotary motion, the direction of motion perceived does not depend on what dot pattern is shown. Second, the time interval between spontaneous flips in perceived direction is lognormally distributed (mode approximately 2 s). These findings suggest the omega effect fits in the category of a typical bistable illusion, and therefore the processes that give rise to this illusion may be the same processes that underlie much of other bistable phenomenon.

This paper is concerned with online personalized navigation services for road network systems in India. We study it as a path cost optimization problem on semi-structured graphs. Existing online services like Google Maps and Live Search Maps do not yet provide road navigation for India. Our strategy is based on the cognitive clustering process that humans use for finding a route between a source-destination pair over a real road network. A semi-automatic web based tool has been developed for collaborative community assisted creation of road maps by leveraging Google Maps services. Our experiments over real route maps indicate that the proposed algorithm performs very well with caching and provides more accurate navigational directions when compared with available web-based map services for Indian road network system.

Male subfertility is an important clinical entity. It entails direct medical, financial, and psychological impact on the couple. A standardization of protocol in its management is yet to be achieved. Detailed workup of the males presenting with subfertility is necessary to elucidate the etiology and prognosticate the disease. Microsurgical reconstruction holds an important place in the management of obstructive disease of male genital tract. With the advent of microsurgical sperm retrieval techniques, couples have a chance to become the biological parents in the cases of nonobstructive azoospermia. All available treatment options should be given to patients to help them achieve a long-term possibility of spontaneous conceptions.

We report successful use of methyl-prednisolone in a 21-month old child with ARDS that did not improve with conventional therapy. The child improved and could be extubated after 10 days of methylprednisolone therapy. Subsequently, the child was weaned off supplementary oxygen. Methylprednisolone appeared to be safe and effective in a child with unresolving ARDS.

Renal cell carcinoma associated with fused ectopic kidneys has rarely been reported in the literature. Here we report the first case of robot-assisted heminephrectomy for chromophobe renal cell carcinoma in an L-shaped fused ectopic kidney. The present case report highlights the importance of three-dimensional vision and enhanced maneuverability with the EndoWrist technology of the robotic surgical system for precise dissection. This report also highlights the importance of preoperative contrast-enhanced computed tomography with three-dimensional arterial reconstruction for surgical planning.

Context: The concept of visceral fat and its role in various metabolic disorders is well-known. Epicardial fat (EF) is also visceral fat, and very few studies are done, especially in the Indian subcontinent. Aims: To study and establish the relationship of EF thickness (EFT) and abdominal visceral fat thickness (VAT) in obese and nonobese type 2 diabetics and to evaluate the usefulness of EFT as a marker of visceral adiposity. Settings and Designs: This cross-sectional study was carried out in the Department of Medicine, JSS Hospital, Mysore, India, between October 2012 and October 2014. Materials and Methods: A total of 68 patients were studied. Patients underwent transthoracic echocardiography and ultrasound abdomen. EFT and VAT were measured. Statistical Analysis: SPSS version 17.0 (SPSS Inc., Chicago, IL, USA) was used. T-test used for comparing quantitative variables. Correlation analysis was done using Pearson correlation test. P ≤ 0.05 was considered statistically signifi cant. Kruskal-Wallis and Mann-Whitney test were used for analysis. Results: The mean value of EFT was 5.92 mm, 7.43 mm, 12.97 mm, 11.27 mm, and 13.8 mm for nonobese, obesity Grade I, II, III, and morbid, respectively (P < 0.0001). The mean EFT between nonobese and obese diabetics was 5.92 mm and 10.2 mm, respectively (P < 0.0001). The mean VAT between nonobese and obese diabetics was 16.58 mm and 38.53 mm, respectively. EFT was signifi cantly correlating with VAT in obese diabetics. Conclusion: EFT and VAT were signifi cantly correlated among obese diabetics while not significantly correlated among nonobese diabetics, suggesting obesity is an independent risk factor for visceral adipose tissue deposition both in abdomen as well as in epicardial surface.

Intraosseous ganglion is a benign bony cyst that mainly involves the epiphysis and metaphysis of long bones. Intraosseous ganglions are rare in talus, and in all the cases reported in literature, the patients had symptoms pertaining to the ankle joint. No case has been reported where the lesion in the talus has caused symptoms specific to the subtalar joint. A 20-year-old female presented to our hospital with pain in the right foot from last 6 months. Ankle joint movements were within normal limits, but the subtalar movement were significantly reduced. Plain radiographs of the foot and ankle were normal. Computed tomography (CT) scan of the foot and ankle showed a cystic lesion (0.5 × 0.5 cm) involving the base of the talar body which communicated with the subtalar joint. The patient was treated by curettage of the lesion through a curvilinear incision over the medial aspect of the subtalar joint. The clinical results after 3 months were excellent. The patient returned to her regular and light recreational activities with full, painless range of motion. There was no recurrence of symptoms at 6 months. Intraosseous ganglion is of talus is a rare entity. Symptomatic patient should be treated surgically.

In this paper, we review the current status of the hybrid silicon photonic integration platform with emphasis on its prospects for increased integration complexity. The hybrid silicon platform is maturing fast as increasingly complex circuits are reported with tens of integrated components including on-chip lasers. It is shown that this platform is well positioned and holds great potential to address future needs for medium-scale photonic integrated circuits.

We report on silicon fab-compatible non-gold ohmic contacts to n-InP and p-InGaAs using Ti/W and Pd/Ge/W based metallization schemes where gold is replaced by aluminum as a thick probe layer. Specific contact resistivity of