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We focus on deterministic global optimization (DGO) for nonconvex parameter estimation problems. Realistic and accurate solutions often require a fitting against very large measurement data sets, resulting in intractable size for DGO. Thus, we aim at accelerating the branch-and-bound algorithm by using reduced data sets for constructing valid bounds. We focus on fitting the equation of state for propane, which is of high interest for the chemical industry. The resulting estimation problem is a challenging nonconvex mixed-integer nonlinear optimization problem. We investigate the validity of using reduced data sets by comparing how the lower and upper bounds change when replacing the full data set with different reduced data sets. We account for regions with high and low quality fits by considering the results for the whole feasible region and 100 different subregions. Our results indicate that both regions containing solution candidates and regions containing only low quality fits can be identified based on reduced data sets. Moreover, we observe that the average CPU time per branch-and-bound iteration typically decreases if reduced data sets are used. [ABSTRACT FROM AUTHOR]

An algorithm is proposed for the global solution of semi-infinite programs (SIPs) without convexity assumptions. It terminates finitely with a guaranteed feasible point, and a certificate of ϵ  f -optimality. The only assumptions are continuity of the functions and existence of an ϵ  f -optimal SIP-Slater point. The lower and upper bounds are obtained by the solution of two nonconvex nonlinear programs (NLP) each, thus shifting the nonconvexity to the global NLP solver. The main contribution of this article is a new procedure for the generation of feasible points. These are obtained by a restriction of the constraints right-hand side by ϵ g  > 0 and a successively finer discretization of the parameter set. A suitable decreasing sequence of ϵ g  → 0 leads to convergence of the generated upper bound. The converging lower bound is obtained by successively tighter discretization, following the principle of Blankenship and Falk [Infinitely constrained optimization problems, J. Optim. Theory Appl. 19 (1976), pp. 261–281]. A proof of convergence is given along with a prototype implementation in general algebraic modelling system. The algorithm is extended to problems with multiple constraints as well as mixed-integer problems. Literature and new problems are solved numerically. The algorithm is extremely simple to implement, but nevertheless very efficient compared to existing methods for nonconvex lower level programs. [ABSTRACT FROM PUBLISHER]

Selective amygdalohippocampectomy (SelAH) is now widely used in the surgical treatment of patients with medically intractable medial temporal lobe epilepsy (MTLE). We present our single-centre experience of a uniform series of drug-resistant MTLE patients treated exclusively with SelAH. A retrospective study of 50 adult patients (25 males, 25 females, mean age 34 years) suffering from medically intractable MTLE was conducted. All patients has been investigated under the same protocol and operated by SelAH performed by one surgeon. Immediate and long-term follow-up was also available and is presented. Forty-two patients (84%) became seizure free (Engel's I); eight of them (16%) were classified as Engel's II; four (8%) as Engel's III; and one as Engel's IV (2%). In 42 of them the final result has been achieved after a single operation, while in the rest eight after a second or third surgical procedure. The mean follow-up period was 6.2 years. Two permanent complications (4%) with no treatment-related mortality have been detected. SelAH performed in well selected cases, where concordance between electrophysiological and MR findings exists, can be a safe and effective surgical treatment method for medically intractable MTLE. [ABSTRACT FROM AUTHOR]

We present a very rare case of hemifacial spasm in a 58-year-old patient who was predisposed by focal temporal bone hyperostosis. The patient presented with a 6-year history of progressive left hemifacial spasm, unresponding to the conservative treatment. She underwent a typical microvasular decompression procedure, during which an unusual local hyperostosis of the interior surface of the left temporal bone was found, distorting the adjacent AICA and causing significant pressure on the facial nerve. The postoperative course was uneventful and in the 24-month follow up, the patient is spasm free. [ABSTRACT FROM AUTHOR]

The goal of this paper is to describe recent attempts to define the stewardship concept and to translate it into action on the ground. The focus is on national forest lands and the unique challenges federal land managers face in working with the public to implement a concept that has different meanings to a variety of stakeholders. Stewardship requires more flexibility than is often found under existing administrative authorities. Large, bureaucratic agencies face many barriers in applying creative and innovative solutions to existing problems, not the least of which are internal and external reward structures. While there exist some authorities that allow for the creative testing of stewardship contracting projects on the ground, a number of challenges remain. Two significant ones are: (1) the need for a clearer, consistent understanding (by both Forest Service employees and constituents) of the authorities that can be used to test stewardship concepts; and (2) a more broad-based agreement on the desired outcome of stewardship projects. Given the current lack of understanding and agreement on how to implement stewardship concepts, the most effective means of moving the issue forward will be to apply innovative tests of contracting methods under current or new temporary authorities. These tests should be designed, implemented, monitored, and evaluated using broad-based, inclusive, on-the-ground coalitions that create effective ties and linkages between local and national levels. [ABSTRACT FROM PUBLISHER]

Discusses the element of stewardship in community-based ecosystem management in the U.S. Characteristics of stewardship; Difference of stewardship from community-based ecosystem management efforts; Factors to achieving effective stewardship within community-based ecosystem management efforts.

This article describes intracranial plasmacytoma as chronic subdural haematoma. A 62-year-old man was admitted in the Department of Neurosurgery, 'G. Gennimatas" Athens General Hospital, suffering from progressive headache with vomiting, dizziness, difficulty in concentration and behavioural changes, more obvious during the past month, after a head injury during a car accident. Neurological examination revealed signs of increased intracranial pressure and a slight left hemiparesis, more obvious in the upper extremity with positive Barre's pyramidal sign.