Maximizing throughput in zero-buffer tandem lines with dedicated and flexible servers

Abstract For tandem queues with no buffer spaces and both dedicated and flexible servers, we study how flexible servers should be assigned to maximize the throughput. When there is one flexible server and two stations each with a dedicated server, we completely characterize the optimal policy. We use the insights gained from applying the Policy Iteration algorithm on systems with three, four, and five stations to devise heuristics for systems of arbitrary size. These heuristics are verified by numerical analysis. We also discuss the throughput improvement, when for a given server assignment, dedicated servers are changed to flexible servers

The Effect of the Marketing Mix and Specialized Knowledge on the Export Performance of SMEs Exporting Dry Fruits

Export is a crucial driver of economic growth in various countries and significantly contributes to a country's entry into global markets and enhances economic success. In developing countries such as Iran, economic and social development programs prioritize the expansion of exports, particularly high value added agricultural products. The growth in non-oil exports, such as dried fruits, and the entry of domestic producers into new global markets have led to an increased demand for Iran's export products. This has also resulted in higher production levels, increased employment opportunities, and higher value added in the related activities. To enhance export performance, which is a crucial measure of a company's success in utilizing its resources and capabilities in the international arena over a specific period of time, it is important to focus on improving marketing strategies and specialized knowledge. Therefore, this research aims to examine the impact of marketing mix and specialized marketing knowledge on the export performance of small and medium-sized enterprises (SMEs) involved in exporting dried fruits in Mashhad, Iran in 2022. A total of 80 questionnaires were distributed among senior managers, board members, and business managers of dried fruits SMEs using the available sampling method. Structural equation modeling was employed for data analysis and test of research hypotheses. The statistical data and structural equation modeling revealed that the joint impact of marketing mix and specialized marketing knowledge has a positive and significant influence on export performance. In order to improve the company's profitability, it is essential for senior managers and sales managers to recognize the significance of these two factors and undergo relevant training to acquire the necessary skills. Moreover, managers should make effective use of appropriate distribution channels to expand their exports. Simultaneously, they should consider adapting product quality and packaging to align with the preferences of foreign buyers

First record of the seed-eating wasp, Systole eremodauci (Hym.: Eurytomidae) from Iran

The family Eurytomidae includes economically important wasps, which feed on the seeds of various agricultural, horticultural and rangeland plants. This report is part of a survey conducted during 2009-2012 to identify the seed-eating pests of non-legume rangeland plants in the Fars province of Iran. The eurytomid species Systole eremodauci Zerova, 1994 was collected on ammoniacum plant, Dorema ammoniacum (D. Don.), and is first recorded from Iran

Etk/Bmx tyrosine kinase activates Pak1 and regulates tumorigenicity of breast cancer cells

Etk/Bmx, a member of the Tec family of nonreceptor protein-tyrosine kinases, is characterized by an N-terminal pleckstrin homology domain and has been shown to be a downstream effector of phosphatidylinositol 3-kinase. P21-activated kinase 1 (Pak1), another well characterized effector of phosphatidylinositol 3-kinase, has been implicated in the progression of breast cancer cells. In this study, we characterized the role of Etk in mammary development and tumorigenesis and explored the functional interactions between Etk and Pak1. We report that Etk expression is developmentally regulated in the mammary gland. Using transient transfection, coimmunoprecipitation and glutathioneS-transferase-pull down assays, we showed that Etk directly associates with Pak1 via its N-terminal pleckstrin homology domain and also phosphorylates Pak1 on tyrosine residues. The expression of wild-type Etk in a non-invasive human breast cancer MCF-7 cells significantly increased proliferation and anchorage-independent growth of epithelial cancer cells. Conversely, expression of kinase-inactive mutant Etk-KQ suppressed the proliferation, anchorage-independent growth, and tumorigenicity of human breast cancer MDA-MB435 cells. These results indicate that Pak1 is a target of Etk and that Etk controls the proliferation as well as the anchorage-independent and tumorigenic growth of mammary epithelial cancer cells

Basic effects of pulp refining on fiber properties- a review

The requirement for high quality pulps which are widely used in paper industries has increased the demand for pulp refining (beating) process. Pulp refining is a promising approach to improve the pulp quality by changing the fiber characteristics. The diversity of research on the effect of refining on fiber properties which is due to the different pulp sources, pulp consistency and refining equipment has interested us to provide a review on the studies over the last decade. In this article, the influence of pulp refining on structural properties i.e., fibrillations, fine formation, fiber length, fiber curl, crystallinity and distribution of surface chemical compositions is reviewed. The effect of pulp refining on electrokinetic properties of fiber e. g., surface and total charges of pulps is discussed. In addition, an overview of different refining theories, refiners as well as some tests for assessing the pulp refining is presented. (C) 2014 Elsevier Ltd. All rights reserved

Tychiini and Mecinini (Coleoptera: Curculionidae, Curculioninae) of Iran: eleven species recorded for the first time, with new data on host plants and distribution of several species

A faunistic study on the tribes Tychiini and Mecinini (Curculionidae, Curculioninae) was carried out during the years 2010-2013 in different ecological regions of Iran. Twenty nine species belonging to the genera Mecinus Germar, 1821, Gymnetron Schoenherr, 1825, Rhinusa Stephens, 1829, Cleopomiarus Pierce, 1919, Tychius Germar, 1817 and Sibinia Germar, 1817 were collected. Localities and ecological notes on each species are provided. Among these, The following 11 species are new to the Iranian fauna: Mecinus crassifemur (Arzanov, 1991), Mecinus simus (Mulsant & Rey, 1859), Gymnetron linkei Reitter, 1907, Rhinusa antirrhini (Paykull, 1800), Rhinusa brondelii (H. Brisout de Barneville, 1862), Rhinusa florum (Rübsaamen, 1895), Tychius reitteri Faust, 1889, Tychius tridentinus Penecke, 1922, Sibinia aureofulva (Desbrochers des Loges, 1875), Sibinia pellucens (Scopoli, 1772), Sibinia unicolor Fảhraeus, 1843, whereas all other 18 species are new for one or more provinces. Host plants of several species reported for the first time and commented as well

Oak cynipid gall inquilines of Iran (Hym.: Cynipidae: Synergini), with description of new species

Ten known cynipid inquiline species associated with oak cynipid galls (Hymenoptera, Cynipidae: Synergini and Cynipini), their distribution and host associations are given for the first time for the Iranian cynipid fauna: Ceroptres cerri Mayr, C. clavicornis Hartig, Saphonecrus haimi (Mayr), Synergus gallaepomiformis (B. de Fonsc), S. pallidipennis Mayr, S. pallipes Hartig, S. reinhardi Mayr, S. thaumacerus (Dalman), S. umbraculus (Olivier) and S. variabilis Mayr. Five new species of cynipid inquilines, Saphonecrus irani Melika & Pujade-Villar sp. n., Synergus acsi Melika & Pujade-Villar sp. n., Synergus bechtoldae Melika & Pujade-Villar sp. n., Synergus palmirae Melika & Pujade-Villar sp. n. and Synergus mikoi Melika & Pujade-Villar sp. n. are described from Iran; the description and diagnosis of adults of these new species, their host associations and biology are given. Finally, galls that may induce by the inquiline Synophrus olivieri Kieffer have been collected