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Let [Formula: see text] be a connected graph and [Formula: see text] be the distance between the vertices [Formula: see text] and [Formula: see text] in [Formula: see text]. The diameter of [Formula: see text] is defined as [Formula: see text] and is denoted by [Formula: see text]. A subset of vertices [Formula: see text] is called a resolving set for [Formula: see text] if for every two distinct vertices [Formula: see text], there is a vertex [Formula: see text], [Formula: see text], such that [Formula: see text]. A resolving set containing the minimum number of vertices is called a metric basis for [Formula: see text] and the number of vertices in a metric basis is its metric dimension, denoted by [Formula: see text]. Metric dimension is a generalization of affine dimension to arbitrary metric spaces (provided a resolving set exists). Let [Formula: see text] be a family of connected graphs [Formula: see text] depending on [Formula: see text] as follows: the order [Formula: see text] and [Formula: see text]. If there exists a constant [Formula: see text] such that [Formula: see text] for every [Formula: see text] then we shall say that [Formula: see text] has bounded metric dimension, otherwise [Formula: see text] has unbounded metric dimension. If all graphs in [Formula: see text] have the same metric dimension, then [Formula: see text] is called a family of graphs with constant metric dimension. In this paper, we study the metric properties of an infinite class of circulant graphs with three generators denoted by [Formula: see text] for any positive integer [Formula: see text] and when [Formula: see text]. We compute the diameter and determine the exact value of the metric dimension of these circulant graphs.

Summary Background Large ventral lateral clock neurons (lLNvs) exhibit higher daytime-light-driven spontaneous action-potential firing rates in Drosophila , coinciding with wakefulness and locomotor-activity behavior. To determine whether the lLNvs are involved in arousal and sleep/wake behavior, we examined the effects of altered electrical excitation of the LNvs. Results LNv-hyperexcited flies reverse the normal day-night firing pattern, showing higher lLNv firing rates at night and pigment-dispersing-factor-mediated enhancement of nocturnal locomotor-activity behavior and reduced quantity and quality of sleep. lLNv hyperexcitation impairs sensory arousal, as shown by physiological and behavioral assays. lLNv-hyperexcited flies lacking sLNvs exhibit robust hyperexcitation-induced increases in nocturnal behavior, suggesting that the sLNvs are not essential for mediation of arousal. Conclusions Light-activated lLNvs modulate behavioral arousal and sleep in Drosophila .

Engineering studies consist of two parts: theory lectures and laboratory practices. Effectiveness of laboratories plays an important role in providing necessary design skills. However, evaluation of laboratories can be subjective and inconsistent. Consequently, a criterion is required to evaluate the engineering laboratories. This paper proposes an evaluation criterion for assessing the effectiveness of engineering laboratories in terms of pedagogic aspects. The identified pedagogic aspects in this paper are: relationship between theory and laboratory practice, content level, activity level, learning environment and laboratory manual. We evaluated seven different laboratories and generated recommendations based on our evaluation results.

The present work deals with the development of a newly designed free electrolytic diffusion approach (the distribution of charge over microelectrodes) for the purification of metals and was successfully applied for the purification of nickel from the industrial effluent containing high proportion of nickel. Atomic absorption spectrophotometer (AAS) analyzed the purified nickel deposited on working microelectrodes. The results obtained show that the purity of nickel was enhanced from 95% to 99.9% with traces of copper etc. It was concluded that distribution of charge over the microcathodes at a rate of 50 cycles per second (cps) shows better results for the production of high purity (HP) nickel as compared to 25 cycles per second (cps).

Acute transient parotid gland enlargement in association with general anesthesia is a rare complication and has also been called anesthesia mumps. Unilateral or bilateral parotid or submandibular swelling usually develops during surgery under anesthesia or, a few hours later and usually resolves in a few days with no sequelae. It has been reported as a complication after general anesthesia in patients undergoing spinal surgeries in prone and lateral decubitus position, even after cesarean section in the supine position and also reported in Intensive Care Unit patients. We present a case of a unilateral parotid swelling noticed in immediate postoperative course, in a patient who underwent spine surgery.

To determine whether endurance exercise training can alter the β-adrenergic-stimulated inotropic response in older women, we studied 10 postmenopausal healthy women (65.4 ± 0.9 yr old) who exercised for 11 mo. Left ventricular (LV) function was evaluated with two-dimensional echocardiography during infusion of isoproterenol after atropine. Maximal O2 consumption increased 23% in response to training (from 1.35 ± 0.06 to 1.66 ± 0.07 l/min; P = 0.004). Training had no effect on baseline LV function, end-diastolic diameter, LV wall thickness, or LV mass. The increase in LV systolic function in response to isoproterenol was unaffected by training. Furthermore, neither the systolic shortening-to-end-systolic wall stress relationship nor the end-systolic wall stress-to-end-systolic diameter relationship during isoproterenol infusion changed with training. We conclude that older postmenopausal women can increase their maximal O2consumption with exercise training without eccentric LV hypertrophy or enhancement of β-adrenergic-mediated LV contractile function. These observations provide an explanation for the finding that maximal cardiac output and stroke volume are not increased in older women in response to training.

Atta-ur-Rahman Institute for Natural Product Discovery, Universiti Teknologi MARA, Puncak Alam Campus, 42300 Bandar Puncak Alam, Selangor D. E. Malaysia; Faculty of Applied Science Universiti Teknologi MARA, 40450 Shah Alam; Faculty of Pharmacy, Universiti Tecknologi MARA, Puncak Alam 42300, Selangor, Malaysia; H.E.J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi, Karachi75270, Pakistan; E-mail: taha_hej@yahoo.com