Suchergebnisse

Abstract
Cadmium (Cd) is a widespread environmental pollutant. A number of observational studies have reported that Cd might be a cause of nasopharyngeal (NPC), pharyngeal (PC), or laryngeal cancers (LC). In this study evidence about the relation of Cd and NPC, PC, and LC has been summarized. A literature review was conducted until 20 June 2020 in PubMed, Ovid, Scopus, Web of Science and Google scholar databases to investigate the epidemiologic evidence for the relation between cadmium exposure and cancers of the nasopharynx, pharynx, and larynx. Ten articles were selected after careful screening of retrieved studies. All of these studies obtained a Newcastle-Ottawa Scale (NOS) quality score from 6 to 8. Due to high heterogeneity, in all analyses, random effect was used. The pooled results showed that cadmium levels in NPC (standard mean difference (SMD=0.55; 95% CI=0.20, 0.89; p=0.002) and PC (SMD=9.79; 95% CI=0.62, 18.96; p=0.036) patients/tissues were significantly higher than their controls. But cadmium levels were not significantly different between LC cases/tissues and their controls. (SMD=−0.05; 95% CI=−0.99, 0.89; p=0.921). Exposure to cadmium is likely to cause nasopharyngeal and pharyngeal cancer.

The Persian Gulf has always been the focus of regional and international actors because of its geopolitical position and the large volume of energy reserves. These features have made security a top priority for countries in the region; but differing views on security have prevented the formation of trust and cooperation among regional actors. Saudi Arabia, despite its unique political structure, has an undeniable and influential power in the region. Saudi Arabia's security strategies as one of the key players in the Persian Gulf security equations include: Partnership and Coalition with the West (US); Regional Partnerships within the Persian Gulf Cooperation Council; Coalition with Arab and non-Arab actors and increasing the military power. The main purpose of this paper is to examine the reasons for adopting these strategies. The research method used in this paper to achieve the purpose is the descriptive-analytical method and the library method was used to collect information. The paper's hypothesis is this: It seems that the reasons for adopting these strategies should be sought in Saudi Arabia's lower power than Iran and its efforts to maintain the status quo in the region.

Abstract. In this investigation, relations between the ground's thermal properties and 70 earthquakes with a magnitude >4 Richter in the Alborz region during a period of 12 years (1992 to 2004) were studied. Typical changes of ground temperature, 0.4 °C; thermal diffusivity, 0.028 m2 s−1×10−6 and ground heat flux take place a few hours prior to the earthquakes. The values of thermal diffusivity depend on the ground moisture content, which may change during seismic activities. The analysis of ground heat flux from the epicentre and it's surrounding regions show some anomalous behavior before the earthquakes but with different signs in the areas close to the sea and far away from the sea. The changes of the ground's thermal properties prior to the earthquakes in the Alborz region are attributed to the increase in seismic activities in the epicentre and it's surrounding regions. The anomalous behavior in the ground thermal properties shows great potential in providing early warning of imminent earthquake.

Ethnicity and nationality are types of modern social identities that have reformed after being globalized. This research tries to study the role of modernity characteristics on ethnic identity. Research data was collected using a researcher-made questionnaire, and 384 students of Islamic Azad University, Tehran North Branch were selected by non-probability random sampling in 2019. The results show the significant relationship between ethnic identity and modernity characteristics, modern lifestyle (r=-0.66), modern identity (r=-0.74), modern socialization (r=-0.40), and purposeful use of virtual social networks (r= 0.31). In other words, ethnic identities are weakened by the tendency of participants to the western beneficial and individualistic patterns and values adapted with law, avoiding and underestimating religious and traditional norms. Meanwhile, virtual social networks as a modernity tool have been an opportunity to state the ethnics political and social demands particularly frontiersmen such as Kurds and Turks. Principally, they have appeared in the form of dramatic movements and inter-ethnic tensions that following modernity elements finally reduces ethnical belongings and tendency to the global identity, and only purposeful and conscious use of virtual space can bring integrity and vitality of ethnic identity. In addition, it has unified, awakened, and sued ethnics all over the national borders because of mutual history and identity. According to the results of research, the ethnic belonging of Kurdish and Turkish students was higher than others, and these ethnicities have more complete awareness about their history, epic, land, ethnic customs, rituals, industry, style of clothing, and local cuisine. In addition, they adhered to marriage, companionship, and cooperation with their people and were proud of their native names. ; La etnicidad y la nacionalidad son tipos de identidades sociales modernas que han sido reformadas después de ser globalizadas. Esta investigación busca estudiar el papel de las características de la modernidad en la identidad étnica. Los datos de la investigación se recopilaron mediante un cuestionario elaborado por un investigador, y 384 estudiantes de la Universidad Islámica Azad, Teherán North Branch fueron seleccionados por muestreo aleatorio no probabilístico en 2019. Los resultados muestran la relación significativa entre la identidad étnica y las características de la modernidad, estilo de vida moderno (r = -0.66), identidad moderna (r = -0.74), socialización moderna (r = -0.40) y uso intencionado de redes sociales virtuales (r = 0.31). En otras palabras, las identidades étnicas se debilitan por la tendencia de los participantes a los patrones y valores beneficiosos e individualistas occidentales adaptados con la ley, evitando y subestimando las normas religiosas y tradicionales. Mientras tanto, las redes sociales virtuales como herramienta de modernidad han sido una oportunidad para expresar las demandas étnicas políticas y sociales, en particular los hombres de la frontera como los kurdos y los turcos. Principalmente, han aparecido en forma de movimientos dramáticos y tensiones interétnicas que al seguir los elementos de la modernidad finalmente disminuyen las pertenencias étnicas y la tendencia a la identidad global, y solo el uso deliberado y consciente del espacio virtual puede aportar integridad y vitalidad a la identidad étnica. Además, ha unificado, despertado y demandado a las etnias en todas las fronteras nacionales debido a la historia y la identidad mutuas. Según los resultados de la investigación, la pertenencia étnica de los estudiantes kurdos y turcos fue mayor que la de otros, y estas etnias tienen una conciencia más completa sobre su historia, épica, tierra, costumbres étnicas, rituales, industria, estilo de ropa y cocina local. Además, se adhirieron al matrimonio, la asociación y la cooperación con su gente y estaban orgullosos de sus nombres nativos.

"This book is a comprehensive and up-to-date resource for operations researchers, management scientists, industrial engineers, and other business practitioners and specialists looking for systemic and advanced discussions of supply chain management"--Provided by publisher

The topological indices are functions on the graph that do not depend on the labeling of their vertices. They are used by chemists for studying the properties of chemical compounds. Let be a simple connected graph. The Hyper-Zagreb index of the graph , is defined as ,where and are the degrees of vertex and , respectively. In this paper, we study the Hyper-Zagreb index and give upper and lower bounds for .

A 10-bit pipelined Analog to Digital converter is proposed in this paper with using 0.18 µm TSMC technology. In this paper, a new structure is proposed to increase the speed of the pipeline analog to digital convertor. So at the first stage is not used the amplifier and instead the buffer is used for data transfer to the second stage. The speed of this converter is 350MS/s. An amplifier circuit with accurate gain of 6 and a very accurate unit gain buffer circuit that are open loop with a new structure were. used. In this Converter, the first 3 bits are extracted simultaneously with sampling. The proposed analog-to-digital converter was designed with the total power consumption 75mW using power supply of 1.8v.