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Os(bptpy)2(PF6)2-mediated decarboxylation of oxamic acids under near-infrared irradiation in the presence of alcohols and heterocycles provide urethanes and heterocyclic amides respectively.

This review article describes the recent development in the chemistry of carbamoyl radicals generated from oxamic acids. This mild and efficient method compares well with previous methods of generation of these nucleophilic radicals. The oxidative decarboxylation of oxamic acids can be mediated through thermal, photochemical, electrochemical or photoelectrochemical means, generating carbamoyl radicals, which may further add to unsaturated systems to provide a broad range of important amides. Oxidative decarboxylation of oxamic acids also offers a straightforward entry for the preparation of urethanes, ureas, and thioureas.

In semiconductor industry, CD-SEMs (critical dimension scanning electron microscopes) are key enablers for metrology and process control. Additional applications that exploit the potential of CD-SEM equipment have being developed – such as contour extraction algorithms, in order to continue to address the increasing metrology requirements of the semiconductor industry. An important example of the utilization of image information is the industry’s use of full contour extraction for various applications, such as MPC (mask process correction) modeling, OPC (optical proximity correction) modeling, and advanced measurement solutions, especially for newer technologies such as ILT (Inverse Lithography Technology), where the characteristics of the 2D curvilinear patterns are such that standard measurement solutions are no longer an option. As mask errors become more and more critical, providing good measurements is critical for calibrating MPC models, estimating etch bias over complex features, providing CD uniformity analysis, among other. More complex patterns also lead to less robust measurements in traditional CD-SEMs requiring more refined algorithms and statistics control to achieve a good level of certainty. Tool drift can lead to a lack of focus during the image acquisition and induce a blur problem in the image, affecting the quality of the signal to be analyzed, and consequently misleading the measurements. These measurements can induce false statistics and lead to bad decisions in a fab environment. Another important factor for considering over SEM images is the quality of the signal on the pattern edges. This characteristic may have a significant impact over the measurement results, also leading to errors in the production flow. For example, using wrong measurements for addressing etching recipes or for generating MPC models may induce errors in the mask fabrication process, reducing its overall quality. Therefore, being capable of identifying blur on SEM images as well as edge quality variation is an important tool for mask manufacturers to prevent from using erroneous measurements for the decisions required during the entire fabrication flow. In this work, the impact of blur on CD-SEM measurements is evaluated. Also, the impact of the blur over the detection of pattern’s edges is demonstrated over experimental data, coming from three different mask production flows, with different etch signatures and acquisition conditions. The proposed approach enables removing untrustworthy measurements from a calibration or a verification set.

A soft cervical collar is a simple-to-use, noninvasive, nonintrusive, cheap and comfortable external support that can be used after cervical surgery or injuries such as whiplash [1, 2]. It limits cervical and head movements such as antero-posterior flexion/extension and backward motion of the mandible [3, 4]. In obstructive sleep apnoea (OSA), upper airway obstruction can be caused by anterior flexion of the head or by backward seesaw motion of the mandible and the tongue in supine position [3, 5–7]. Prior to a randomised controlled trial (RCT) using such a support to treat OSA, we assessed in a pilot study 1) night tolerance of the soft cervical collar in patients with OSA; 2) alteration of pharyngeal patency according to polygraphy data with this support in OSA; and 3) trial population size for conclusive results., In severe obstructive sleep apnoea, a soft cervical collar was well tolerated at night in 10 patients with no changes in polygraphy results. With the same design, a randomised controlled trial would need 246 inclusions for conclusive results. https://bit.ly/2KiU3j1

Tech clusters like Silicon Valley play a central role for modern innovation, business competitiveness, and economic performance. This paper reviews what constitutes a tech cluster, how they function internally, and the degree to which policy makers can purposefully foster them. We describe the growing influence of advanced technologies for businesses outside of traditional tech fields, the strains and backlash that tech clusters are experiencing, and emerging research questions for theory and empirical work.

In advanced technology nodes, layout regularity has become a mandatory prerequisite to create robust designs less sensitive to variations in manufacturing process in order to improve yield and minimizing electrical variability. In this paper we describe a method for designing regular full custom layouts based on design and process co-optimization. The method includes various design rule checks that can be used on-the-fly during leaf-cell layout development. We extract a Layout Regularity Index (LRI) from the layouts based on the jogs, alignments and pitches used in the design for any given metal layer. Regularity Index of a layout is the direct indicator of manufacturing yield and is used to compare the relative health of different layout blocks in terms of process friendliness. The method has been deployed for 28nm and 40nm technology nodes for Memory IP and is being extended to other IPs (IO, standard-cell). We have quantified the gain of layout regularity with the deployed method on printability and electrical characteristics by process-variation (PV) band simulation analysis and have achieved up-to 5nm reduction in PV band.

This paper studies the short- and long-term effects of nocturnal oxygen therapy (NOT) on sleep apnea in chronic heart failure (CHF). We enrolled 51 adults in New York Heart Association (NYHA) heart failure functional classes II or III, ≤45 % left ventricular ejection fraction (LVEF), in a randomized, open, single-center study. Nocturnal cardiorespiratory polygraphy showed sleep apnea [apnea-hypopnea index (AHI) ≥15 events/h] in 33 patients, of whom 19 were randomly assigned to NOT, 3.0 l/min, and 14 to no NOT. The NOT group underwent follow-up polygraphy at 24 h and 6 months, and the no NOT group a single follow-up polygraphy at 6 months. No significant difference was observed between baseline and 6 months in the no NOT group. In the NOT group, AHI decreased from 36.8 ± 2.6 events/h at baseline to 20.8 ± 3.0 at 24 h and to 18.3 ± 2.4 at 6 months (both P

28nm metal 90nm pitch is one of the most challenging processes for computational lithography due to the resolution limit of DUV scanners and the variety of designs allowed by design rules. Classical two dimensional hotspot simulations and OPC correction isn’t sufficient to obtain required process windows for mass production. This paper shows how three dimensional resist effects like top loss and line end shortening have been calibrated and used during the OPC process in order to achieve larger process window. Yield results on 28FDSOI product have been used to benchmark and validate gain between classical OPC and R3D OPC.

Aims The prevalence of positive carotid sinus massage (CSM) in asymptomatic elderly persons and related risk of syncope are poorly known. Methods and results We examined the ability of CSM to predict the risk of profound bradycardia or syncope in 30 patients with Alzheimer's disease (AD) and no history of syncope, before treatment with cholinesterase inhibitors. Carotid sinus massage was repeated at 1, 2 and 8 months after onset of cholinergic therapy. The long-term incidence of syncope was observed over a 20-month follow-up. Among the study patients (mean age = 80 ± 6 years, 83% women), 10 had positive CSM, with prolonged ventricular standstill in two of them (6.7%). The response to CSM was not predictive of an increased risk in bradycardia-mediated syncope, though syncope occurred in three patients during long-term follow-up, related to orthostatic hypotension in one and to undetermined causes in the others. Cholinergic therapy in all patients, or drugs that slow cardiac conduction, administered to 40% of the responders to CSM and 45% of the non-responders, or the presence of a bundle branch block did not affect the response to CSM or incidence of syncope. Conclusions A positive CSM was (i) observed in 30% of elderly persons with AD and no history of syncope, and (ii) not predictive of an increased risk of bradycardia-mediated syncope.

With the continuous reduction of layout dimension, critical dimension control becomes more and more tricky. Being one contribution of critical dimension variation, etch bias correction needs to get more accurate. The correction by rule-based optical proximity correction, which only takes into account the distance to the facing outer and inner edges, is reaching its limit at 65nm node. Indeed, its found to be not accurate enough in some particular configurations. Thus, applying etch correction by model-based optical proximity correction looks like a good solution. The etch bias to correct for can be approximated by a function of the local density, obtained by convoluting the design with Kernels. However, it is found to be still not accurate enough in some configurations if the Kernels used for etch modeling are symmetrical, as for optical part. In this study, several etch models are tested to correct etch bias variations of poly layer patterning for 65nm node.

International audience; Assist features (AF) are an essential component of reticle enhancement techniques. Their use is indispensable in sub-100 nm technologies to ensure a maximum process window (PW) across chip, especially for critical levels. Indeed, AF, which can be binary, attenuated or phase-shifted, help in providing a larger PW to the features they assist when they are used in conjunction with off-axis illumination. The depth of focus (DOF) of an isolated structure is improved by the presence of AF by providing to the optical system a diffraction pattern close to the diffraction pattern of a dense structure. The resulting DOF and exposure latitude (EL) are dependent on the relative position of the AF from the main feature. Moreover, the PW varies while inserting one, two or more AF. The relative position of each influences the results. In this paper, a method will be detailed to optimise the placement of the AF. For the purpose of this study, the diffraction pattern induced by the insertion of one or several AF is analysed in frequency space. This analysis details the evolution of the intensity of even and odd orders during the insertion of AF. The calculation of the optimum placement is detailed, and the DOF resulting from the insertion of one or more AF is also presented.

Chronic heart failure (CHF) is a public health problem which affects >2% of the adult population, with high morbidity, mortality, and financial cost. Sleep apnea, prevalent in >50% of patients with CHF, can aggravate vital prognosis due to worsening of heart failure. It is considered that a decrease in the apnea–hypopnea load may improve outcomes for those patients. Nocturnal non invasive ventilation can be proposed to treat sleep apnea in this situation, there being few alternatives. The present review concerns the use of nocturnal oxygen therapy (NOT) in patients suffering from both CHF and sleep apnea. The interest of NOT in this situation lies in its ability to reduce the central apnea–hypopnea index and to improve nocturnal oximetry disorders related to sleep apnea. Impact on cardiac contractility, patient tolerance, side effects, and costs of NOT are also approached as well as the underlying mechanisms of NOT. In addition, the results of the SERVE-HF trial have shown an increased death rate in patients with CHF and central sleep apnea and who were treated with adaptive servo-ventilation versus control patients. This may lead to renewed interest in NOT in those patients.