Plasma and lipoprotein fatty acid composition in glycogen storage disease type I

Nocturnal intragastric feeding has been shown to be an effective means to improve clinical and biochemical features in glycogen storage disease type I (GSD-I). In this study, we investigated the fatty acid patterns in a whole plasma and in circulating lipoproteins in patients on this therapy. The results demonstrated massive concentration of total fatty acids coupled with higher levels of triglycerides, free cholesterol, cholesterol ester and phospholipids. This hyperlipidemia involved all fatty acids without distinction of carbon or bond numbers. However, the increase was more pronounced for saturated than polyunsaturated fatty acids, as was demonstrated by the ratios of both oleic acid to linoleic acid (1.91±0.40 vs 0.80±0.09 in controls) and of ω3+ω6 to ω9 fatty acid families (0.92±0.11 vs 1.66±0.08 in controls). The fatty acid patterns in very low (VLDL), low (LDL) and high (HDL) density lipoprotein showed substantial differences in composition, reflecting an association between an abnormal lipoprotein pattern and essential fatty acid deficiency. Furthermore, GSD-I patients exhibited a significant increase in VLDL (17±2 vs 47±7 mg/dl) and LDL cholesterol (124±7 vs 206±24 mg/dl), coupled with a decrease in HDL cholesterol (49±4 vs 28±3 mg/dl). These data documenting high LDL cholesterol and low HDL cholesterol associated with an increased concentration and proportion of saturated fatty acids suggest that GSD-I patients on nocturnal intragastric feeding are at high risk for atherosclerosis and its complications.     

Predicting and controlling risks from human exposures to vibration and mechanical shock: flag waving and flag weaving

At work or in leisure activities, many people are exposed to vibration or mechanical shocks associated with risks of injury or disease. This paper identifies information that can be used to decide whether there may be a risk from exposure to hand-transmitted vibration or whole-body vibration and shock, and suggests actions that can control the risks. The complex and time-varying nature of human exposures to vibration and shock, the complexity of the different disorders and uncertainty as to the mechanisms of injury and the factors influencing injury have prevented the definition of dose–response relationships well proven by scientific study. It is necessary to wave a flag indicating when there is a need to control risks from exposure to vibration and shock while scientific enquiry provides understanding needed to weave a better flag. It is concluded that quantifying exposure severity is often neither necessary nor sufficient to either identify risks or implement measures that control the risks.Practitioner Summary: The identification of risks associated with exposure to vibration and mechanical shock cannot, and need not, rely solely on the quantification of exposure severity. Qualitative methods can provide a sufficient indication of the need for control measures, which should not be restricted to reducing standardised measures of exposure severity.     

Massively parallel Lucas Kanade optical flow for real-time video processing applications

This paper deals with dense optical flow estimation from the perspective of the trade-off between quality of the estimated flow and computational cost which is required by real-world applications. We propose a fast and robust local method, denoted by eFOLKI, and describe its implementation on GPU. It leads to very high performance even on large image formats such as 4 K (3,840 × 2,160) resolution. In order to assess the interest of eFOLKI, we first present a comparative study with currently available GPU codes, including local and global methods, on a large set of data with ground truth. eFOLKI appears significantly faster while providing quite accurate and highly robust estimated flows. We then show, on four real-time video processing applications based on optical flow, that eFOLKI reaches the requirements both in terms of estimated flows quality and of processing rate.     

To what end? Drip irrigation and the water–energy–food nexus in Morocco

This article draws on three case studies of drip irrigation adoption in Morocco to consider the water–energy–food nexus concept from a bottom-up perspective. Findings indicate that small farmers' adoption of drip irrigation is conditional, that water and energy efficiency does not necessarily reduce overall consumption, and that adoption of drip irrigation (and policies supporting it) can create winners and losers. The article concludes that, although the water–energy–food WEF nexus concept may offer useful insights, its use in policy formulation should be tempered with caution. Technical options that appear beneficial at the conceptual level can have unintended consequences in practice, and policies focused on issues of scarcity and efficiency may exacerbate other dimensions of poverty and inequality.     

A two-phase mathematical-programming heuristic for flexible assignment of activities and tasks to work shifts

In the service industry, workers perform work shifts and are assigned to interruptible activities and uninterruptible tasks during their shifts. The work shifts of regular employees are often established several weeks in advance of the operations when the activity and task demands are still uncertain. Just a few days before the operations when these demands are unveiled with more certainty, the planned schedules can be slightly modified and on-call temporary employees can be scheduled to satisfy the demands as best as possible. As acceptable modifications, extending the planned shifts and moving workers’ meal breaks are considered. In this paper, we are interested in the scheduling problem encountered in this second step, which also involves assigning activities and tasks to the scheduled work shifts. To produce good-quality solutions in fast computational times for large-sized instances, we develop a two-phase heuristic. In the first phase, an approximate mixed-integer programming model is used to suggest temporary shifts and extensions to regular shifts and to schedule and assign tasks. In the second phase, a column-generation heuristic embedded in a rolling horizon procedure determines the final shifts and assigns activities to them. Computational results obtained on randomly generated instances are reported to evaluate the validity of the proposed solution method.     

The Sanaga discharge at the Edea Catchment outlet (Cameroon): An example of hydrologic responses of a tropical rain‐fed river system to changes in precipitation and groundwater inputs and to flow regulation

The Sanaga River is one of Sub‐Saharan Africa's largest and greatly regulated rivers. Available flow data for this hydrosystem largely cover the pre‐ and post‐regulation periods. From comparisons between unregulated (hypothetical) and observed scenarios, it has been possible to separate and to quantify hydro‐climatic (groundwater + rainfall) change effects from anthropogenic impacts (especially dam‐related alterations). To appreciate shifts in the river regime, discontinuity detection tests and the IHA model were applied to discharge data series reflecting average and extreme flow conditions, respectively. Results obtained principally from the Hubert segmentation method reveal that a major discontinuity occurred in 1970–1971 separating a surplus phase between 1945–1946 and 1969–1970, and a deficient and much contrasted one, from 1971/1972. This implies that the Sanaga catchment is dominantly affected by hydro‐climatic changes. However, wide land cover/land use changes experienced here since 1988 have resulted in an increase in surface runoff. Additional quickflows linked to these changes may have partly compensated for the substantial decline in the dry season rainfall and groundwater inputs observed from this date. Although at the monthly scale, dam‐related impacts on average flows increase with stage of regulation, the seasonal variability of the river regime remains generally unaffected. A comparison of the IHA statistics, calculated from unregulated and observed streamflow data, show that hydrologic shifts occurring in maximum and minimum discharges are mostly significant from 1971/1972 and are mainly due to the action of dams. Minimum flows appear, however, widely impacted, thus reflecting the prime objective assigned to the existing reservoirs, constructed to supplement flows for hydroelectricity production during the dry season. Copyright © 2010 John Wiley & Sons, Ltd.     

Development and pilot testing of the Neuromuscular Blockade Advisory System

The neuromuscular blocker advisory system (NMBAS) is a computer program developed to provide advisory guidance to anesthesiologists on the timing and dose of rocuronium to paralyze patients during surgery. It is believed that the use of such a system will administer the minimally effective amount of drug, maintaining the patient in a state of paralysis that is useful for surgery yet easily reversible. This will improve patient safety and result in more efficient care. In this paper we present the NMBAS, its basic methodology, and its development though a pilot study. Novel methods of handling neuromuscular response data are presented, including relaxation measurement and the enhanced-train-of-four sensing modality. New methods of handling nonlinearities at the neuromuscular junction to allow application of adaptive control techniques are presented. A novel form of modelling combining model swapping and RLSE adaptation to accommodate the patient variation seen with NMB drugs is introduced. A pilot study testing the NMBAS was undergone to prepare the NMBAS for application in a full clinical trial, in which patients undergoing prostate brachytherapy surgeries using rocuronium for intubation were admitted.     

A performance study of multiprocessor task scheduling algorithms

Multiprocessor task scheduling is an important and computationally difficult problem. A large number of algorithms were proposed which represent various tradeoffs between the quality of the solution and the computational complexity and scalability of the algorithm. Previous comparison studies have frequently operated with simplifying assumptions, such as independent tasks, artificially generated problems or the assumption of zero communication delay. In this paper, we propose a comparison study with realistic assumptions. Our target problems are two well known problems of linear algebra: LU decomposition and Gauss–Jordan elimination. Both algorithms are naturally parallelizable but have heavy data dependencies. The communication delay will be explicitly considered in the comparisons. In our study, we consider nine scheduling algorithms which are frequently used to the best of our knowledge: min–min, chaining, A^*, genetic algorithms, simulated annealing, tabu search, HLFET, ISH, and DSH with task duplication. Based on experimental results, we present a detailed analysis of the scalability, advantages and disadvantages of each algorithm.

Re-examining the causal structure of information technology impact research

About 20 years ago, Markus and Robey noted that most research on IT impacts had been guided by deterministic perspectives and had neglected to use an emergent perspective, which could account for contradictory findings. They further observed that most research in this area had been carried out using variance theories at the expense of process theories. Finally, they suggested that more emphasis on multilevel theory building would likely improve empirical reliability. In this paper, we reiterate the observations and suggestions made by Markus and Robey on the causal structure of IT impact theories and carry out an analysis of empirical research published in four major IS journals, Management Information Systems Quarterly (MISQ), Information Systems Research (ISR), the European Journal of Information Systems (EJIS), and Information and Organization (I&O), to assess compliance with those recommendations. Our final sample consisted of 161 theory-driven articles, accounting for approximately 21% of all the empirical articles published in these journals. Our results first reveal that 91% of the studies in MISQ, ISR, and EJIS focused on deterministic theories, while 63% of those in I&O adopted an emergent perspective. Furthermore, 91% of the articles in MISQ, ISR, and EJIS adopted a variance model; this compares with 71% from I&O that applied a process model. Lastly, mixed levels of analysis were found in 14% of all the surveyed articles. Implications of these findings for future research are discussed.     

Correction of color information of a 3D model using a range intensity image

Most active optical range sensors record, simultaneously with the range image, the amount of light reflected at each measured surface location: this information forms what is called a range intensity image, also known as a reflectance image. This paper proposes a method that uses this type of image for the correction of the color information of a textured 3D model. This color information is usually obtained from color images acquired using a digital camera. The lighting condition for the color images are usually not controlled, thus this color information may not be accurate. On the other hand, the illumination condition for the range intensity image is known since it is obtained from a controlled lighting and observation configuration, as required for the purpose of active optical range measurement. The paper describes a method for combining the two sources of information, towards the goal of compensating for a reference range intensity image is first obtained by considering factors such as sensor properties, or distance and relative surface orientation of the measured surface. The color image of the corresponding surface portion is then corrected using this reference range intensity image. A B-spline interpolation technique is applied to reduce the noise of range intensity images. Finally, a method for the estimation of the illumination color is applied to compensate for the light source color. Experiments show the effectiveness of the correction method using range intensity images.