Single-mode power dependence on surface relief size formode-stabilized oxide-confined vertical-cavity surface-emitting lasers

We have studied the mode behavior of oxide-confined vertical-cavity surface-emitting lasers (VCSELs) with a surface relief for fundamental mode selection. The dependence of single-mode power on the surface relief diameter was measured and compared with numerically calculated values. VCSELs with diameters of 9 and 12 μm were equipped with surface reliefs with diameters in the range 4-10 μm. The results show that there exists an optimum relief diameter for each VCSEL size. A maximum single-mode power of 2.2 mW was achieved for a 9-μm-diameter VCSEL with a 4-μm-diameter surface relief     

Model-based design: a report from the trenches of the DARPA Urban Challenge

The impact of model-based design on the software engineering community is impressive, and recent research in model transformations, and elegant behavioral specifications of systems has the potential to revolutionize the way in which systems are designed. Such techniques aim to raise the level of abstraction at which systems are specified, to remove the burden of producing application-specific programs with general-purpose programming. For complex real-time systems, however, the impact of model-driven approaches is not nearly so widespread. In this paper, we present a perspective of model-based design researchers who joined with software experts in robotics to enter the DARPA Urban Challenge, and to what extent model-based design techniques were used. Further, we speculate on why, according to our experience and the testimonies of many teams, the full promises of model-based design were not widely realized for the competition. Finally, we present some thoughts for the future of model-based design in complex systems such as these, and what advancements in modeling are needed to motivate small-scale projects to use model-based design in these domains.     

Interleukin-35 Prevents the Elevation of the M1/M2 Ratio of Macrophages in Experimental Type 1 Diabetes

Macrophages play an important role in the early development of type 1 diabetes (T1D). Based on the phenotype, macrophages can be classified into pro-inflammatory (M1) and anti-inflammatory (M2) macrophages. Despite intensive research in the field of macrophages and T1D, the kinetic response of M1/M2 ratio has not been studied in T1D. Thus, herein, we studied the M1 and M2 macrophages in the early development of T1D using the multiple low dose streptozotocin (MLDSTZ) mouse model. We determined the proportions of M1 and M2 macrophages in thymic glands, pancreatic lymph nodes and spleens on days 3, 7 and 10 after the first injection of STZ. In addition, we investigated the effect of IL-35 in vivo on the M1/M2 ratio and IL-35⁺ plasmacytoid dendritic cells in diabetic mice and in vitro on the sorted macrophages. Our results revealed that the M1/M2 ratio is higher in STZ-treated mice but this was lowered upon the treatment with IL-35. Furthermore, IL-35 treated mice had lower blood glucose levels and a higher proportion of IL-35⁺ cells among pDCs. Macrophages treated with IL-35 in vitro also had a higher proportion of M2 macrophages. Together, our data indicate that, under diabetic conditions, pro-inflammatory macrophages increased, but IL-35 treatment decreased the pro-inflammatory macrophages and increased anti-inflammatory macrophages, further suggesting that IL-35 prevents hyperglycemia by maintaining the anti-inflammatory phenotype of macrophages and other immune cells. Thus, IL-35 should be further investigated for the treatment of T1D and other autoimmune disorders.     

Driver behavior in car-to-pedestrian incidents: An application of the Driving Reliability and Error Analysis Method (DREAM)

To develop relevant road safety countermeasures, it is necessary to first obtain an in-depth understanding of how and why safety-critical situations such as incidents, near-crashes, and crashes occur. Video-recordings from naturalistic driving studies provide detailed information on events and circumstances prior to such situations that is difficult to obtain from traditional crash investigations, at least when it comes to the observable driver behavior. This study analyzed causation in 90 video-recordings of car-to-pedestrian incidents captured by onboard cameras in a naturalistic driving study in Japan. The Driving Reliability and Error Analysis Method (DREAM) was modified and used to identify contributing factors and causation patterns in these incidents. Two main causation patterns were found. In intersections, drivers failed to recognize the presence of the conflict pedestrian due to visual obstructions and/or because their attention was allocated towards something other than the conflict pedestrian. In incidents away from intersections, this pattern reoccurred along with another pattern showing that pedestrians often behaved in unexpected ways. These patterns indicate that an interactive advanced driver assistance system (ADAS) able to redirect the driver's attention could have averted many of the intersection incidents, while autonomous systems may be needed away from intersections. Cooperative ADAS may be needed to address issues raised by visual obstructions.     

The diabetic foot. Optimal prevention and treatment can halve the risk of amputation

Almost half of all lower leg amputations are performed in patients with diabetes. In over 70 per cent of these cases, amputation is precipitated by progression of foot ulceration to deep gangrenous infection. Most foot ulcers are preceded by trauma, usually due to ill-fitting shoes, and are precipitated by sensory motor neuropathy with varying degrees of peripheral vascular disease. The Swedish Medical Research Council and the Swedish Institute for Health Services Development arranged a conference on diabetic foot problems in April 1998, the purpose of which was to arrive at a consensus regarding the prevention and management of diabetic foot. It was concluded that a satisfactory multidisciplinary approach should include regular control of feet and footwear, preventive foot care (education, footwear, chiropody), continuous follow-up of high-risk feet, and early recognition of revascularisation. Continuous registration of amputation, irrespective of type, cause and site, might substantially reduce the amputation rate among diabetics. Were such an approach to reduce the incidence of diabetes-related amputation by 50 per cent, annual costs for the management of diabetic foot in Sweden would be reduce by SEK 400 million (the value of improved quality of life not taken into consideration).     

In situ detection of myocardial infarction in pig by measurements of aspartate aminotransferase (ASAT) activity in the interstitial fluid

Recent studies have suggested that the fetal dysmorphogenesis in diabetic pregnancies is associated with an increase in embryonic oxygen-free radicals. This excess of oxygen-free radicals may result from either overproduction or decreased clearance by the enzymatic scavenging mechanism. However, there are no in vivo data on the activity of embryonic oxygen-free radical scavenging enzymes. The purpose of the current study is to investigate whether this increase in embryonic oxygen-free radicals is the result of a change in the activity of the fetal oxygen-free radical scavenging/antioxidant enzymes during pregnancy complicated by maternal diabetes in an in vivo rat model. Thirty-six Sprague-Dawley rats were randomly assigned to one of two study groups: nondiabetic control and an untreated diabetic group. On day 12, fetuses were examined for crown-rump lengths, somite numbers, and external anomalies. The activity of fetal oxygen-free radical scavenging enzymes, including superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (CAT), were determined. The untreated diabetic group of rats had a significantly higher mean blood glucose level than that of the nondiabetic controls and also a significantly lower weight gain, higher resorption rate, smaller embryonic size with lower total protein content, and a approximately 6-fold increase in the rate of fetal neural tube defects compared to the nondiabetic controls. Superoxide dismutase activity was significantly reduced in the embryos with neural tube defects regardless of maternal diabetic status (2.25 +/- 0.83 vs. 1.17 +/- 0.04 u/mg protein; P < 0.05). Glutathione peroxidase and catalase activity were significantly reduced in malformed versus normal-formed embryos of nondiabetic mothers (GPX-2.68 +/- 1.15 vs. 4.46 +/- 1.12 mu/mg protein, CAT -1.67 +/- 0.53 vs 2.49 +/- 0.61 u/mg protein respectively; P < 0.01). However, overall catalase activity was increased in embryos of diabetic mothers as compared to controls. Two-way analysis of variance identified fetal malformations as the variance associated with reduced fetal SOD activity, whereas maternal diabetes was associated with the increase in fetal catalase activity. Neither neural tube defect nor maternal diabetes was found to be the variable affecting fetal GPX activity, Fetal oxygen-free radical scavenging enzymes respond differently to the adverse environment created by maternal diabetes during pregnancy. Defects in embryonic SOD and catalase activity, regardless of maternal diabetic status, may reduce the ability of the fetus to clear free oxygen radicals, thereby exposing it to an increased oxidative load that may cause fetal dysmorphogenesis. The diabetic state of the mothers did not decrease embryonic activity of any of the scavenging enzymes. Therefore, although excess oxidative load, as observed in diabetes, may cause tissue injury and embryopathy, the mechanism does not appear to be a diabetes-induced reduction in the action of the scavenging enzymes.     

Assessment of the relative systemic potency of inhaled fluticasone and budesonide

Studies using dry powder devices have suggested that fluticasone propionate (FP) has a greater systemic effect than budesonide (BUD). The aim of the present study was to investigate and compare the relative systemic potency of FP and BUD from their respective pressurized metered-dose inhalers (pMDIs). A placebo-controlled, open, randomized, cross-over study was conducted in 21 healthy male volunteers. Placebo, BUD (200, 400 and 1,000 micrograms b.i.d.) and FP (200, 375 and 1,000 micrograms b.i.d.) were inhaled for 4 days, with a wash-out period of at least 3 days between treatments. Blood samples for cortisol analysis were drawn during the last 24 h of each treatment period. Cortisol levels, measured as 24 h pooled plasma cortisol, were statistically significantly lower (p = 0.0001) for all dose levels during FP pMDI treatment (21, 39 and 84% suppression from placebo) than during BUD pMDI treatment (1, 3 and 27% suppression from placebo). The relative systemic potency FP:BUD was 3.7:1 (95% confidence interval (95% CI) 2.9-4.8)). The relative systemic potency based on the single 08:00 h samples was 5.2:1 (95% CI 3.0-9.3). In conclusion, in healthy male volunteers using pressurized metered-dose inhalers, fluticasone propionate was shown to have a stronger systemic effect than budesonide.     

Experiments in feedback linearized iterative learning‐based path following for center‐articulated industrial vehicles

This paper describes the design, industrial application, and field testing of a technique for autonomous wheeled‐vehicle path following that uses iterative learning control (ILC) in a feedback linearized space. One advantage of this approach is that ILC is used without having to employ approximate linearization at every time step. The main contribution of this paper is the unique field experiments that used two large industrial‐scale center‐articulated underground mining vehicles. The described field work not only tested the underlying technique on commercial vehicles, but also presents a method for parallel speed learning, wherein the speed is adjusted over subsequent learning trials to improve cycle productivity. Finally, presented are field results for an approach to prelearning through simulation before deployment in the field to reduce the initial path‐following errors.