348 research outputs found
Multiband monopole antenna for mobile applications
β In this paper, a multiband monopole antenna has
been proposed for mobile applications. The monopole antenna
has simple structure with a physical size of 15 cm Γ 7 cm. The
antenna consists of monopole shape loaded by a set of folded
arms with a varying length which lead to a better impedance
matching result and multiband performance. The simulated
results show that the proposed antenna provide multiband
frequency operation of 0.8 GHz, 1.8 GHz 2.1 GHz, 2.6 GHz
and 3.5 GHz which covers the range from 0 to 4 GHz. The
antenna is designed to operate at sub-6 GHz which proposed as
lower frequency band to deliver 5G in early stage. The
designed antenna has been fabricated and measured to validate
the simulated results. RF Coaxial U.FL Connector was used as
the port connector. The measurement results agrees well with
the simulated ones for all frequency bands
Simulation of Coating -Visco-Elastic liquid in the Mico-Nip of Metering Size Press
For a set of operating conditions and coating color formulations, undesirable phenomena like color spitting and coating ribs may be triggered in the Micro-nip during the coating process. Therefore, our interest in this work focus on another parameter affect on the undesirable phenomena as the vortices in the Micro-nip. The problem deals with the flow through the Micro-nip of metering size press. The flow enters and exits at a tangential velocity of 20 m/s between two rollers with diameter 80 cm and 60 -m apart. In the upper and bottom part of the domain the angular velocity is 314 rad /s. It has one sub-domain. Previous studies focus on the Micro-nip without considering the inertia and the viscoelasticity of the material. Roll coating is a technique commonly used in the coating industry to meter a thin fluid film on a moving substrate. During the film formation, the fluid is subjected to very high shear and extensional rates over a very short period of time. The fluid domain changes as a function of the hydrodynamic pressure within the nip as a result of the deformable cover usually used on one of the rolls. The free surface also adds more complexity to the flow due to the force equilibrium in the fluid gas interface. Last of all, the rheological behavior of the coating fluid is usually non-Newtonian, so the metering flow hydrodynamics is finally very difficult to describe. It is concluded that the normal forces of micro-nip increases with increasing the inhibitors. Therefore, it affects on the smoothness and creates defects. On the other hand, it can be concluded that the creation of big vortex in the middle of micro-nip affects on the coating liquid behavior
Recent progress in understanding immune activation in the pathogenesis in HIV-TB coinfection
Purpose of review Tuberculosis is the leading infectious cause of death worldwide, and HIV-1 the best recognized risk factor for active TB. This review focuses on immune complex formation; the interplay of type I and II interferon signaling; and T-cell activation in HIVβTB pathogenesis. Recent findings Circulating immune complexes and complement, and FcΞ³ signaling in whole blood act as early markers of TB disease in HIV-1-infected persons. HIV-1 is associated with a type I interferon response in whole blood, reducing the specificity of TB biomarkers dependent on type I and II interferon genes. Type I and type II interferons are implicated in both protection and TB disease, a protective outcome may depend on modulating these pathways. Whilst M. tuberculosis-specific CD4 T cells are preferentially depleted during HIV-1 infection, activation markers on M. tuberculosis-specific CD4 T cells, in particular HLA-DR, reflect immune activation and have promise as biomarkers of M. tuberculosis disease activity in individuals with HIV-1. Summary TB pathogenesis in HIV-1 involves a complex interaction of underlying activation of both the innate and adaptive immune systems. Further research is required to understand whether biomarkers of activation could be used to predict or quantify TB disease in the context of HIV-1 infection
A comparison of the professional qualifications among teachers graduated from Farhangian University, former Teacher Education Centers and other universities
Background and Objectives:In the ideals proposed by experts for education systems in the twenty-first century, the teacher is mentioned as the fulcrum of any change. Competence is a set of knowledge, skills and abilities of a particular job that makes a person successful in performing tasks. In recent educational research, the term professional competence is used to describe the specific prerequisites that teachers need to succeed in their work. It is assumed that this professional competence can be learned and taught. Professional competence includes having professional knowledge as well as motivational and emotional aspects. Professional knowledge is divided into different types such as content knowledge, pedagogical content knowledge and pedagogical-psychological knowledge. A teacher's competence refers to his or her ability to adequately meet the demands and requirements of the teaching profession, using an integrated set of knowledge, skills, and attitudes that manifest in the teacher's performance and response. Based on the growth model of teachers' professional competence, the psychological characteristics of the teacher seem to play an important role in gaining learning opportunities. In addition, it has been suggested that beyond specific subject knowledge, more aspects of the teacher, such as teachers' beliefs and motivational and emotional characteristics, are important prerequisites for educating and motivating students. The aim of this study is to investigate professional qualifications among teachers graduated from Farhangian University, former Teacher Education Centers and other universities. Methods: The method of the study is causal-comparative. The sample was comprised of 210 teachers in three groups that graduated from Farhangian University, former Teacher Education Centers and other universities such that the groups were similar in demographic factors. All subjects assessed by teacher professional qualifications questionnaire. The results of two-way analysis of variance show that teachersβ professional qualifications in three groups are different. Findings: The results of the cognitive qualification show that Farhangian Universityβs graduates have the best state. In management qualification, the difference between Farhangian Universityβs graduates and former Teacher Education Centersβ graduates is not significant but this difference is significant when other universitiesβ graduates are considered. Attitude qualification difference is not significant between the groups. Conclusion: The results of this study showed that the professional competence of teachers is significantly different. The cognitive competence of Farhangian University graduates is higher than other graduates. Graduates of teacher training centers also have higher cognitive competencies compared to graduates of other universities. In terms of managerial competence, the graduates of Farhangian University have not shown a significant difference with the graduates of teacher training centers, but they are in a better position compared to the group of graduates of other universities. In this case, the difference between former teacher training graduates and other universities is not significant. In attitudinal competence, the difference between groups of teachers is not significant, meaning that these three categories have equally developed attitudinal competence in their graduates
Construction material selection criteria for timber gridshell application: a literature review
Timber gridshells have the potential to be a sustainable and cost-effective solution for long-span applications and free-form architecture. Despite this, their overall use has been limited, and there is a lack of research focusing on their construction materials. This literature review aims to investigate timber gridshells and their construction materials to identify the criteria used in selecting suitable materials for gridshell applications. A review of peer-reviewed scientific articles, books, and theses was conducted to gather information on timber gridshells, construction materials used in gridshells, timber used in active bending structures, and building standards. The research findings identified six main factors that are important when selecting a suitable material for timber gridshell application: structural strength and strength grading, bending strength and behaviour, bending strength/bending elasticity ratio, durability, commercial availability, and cost. These findings are also discussed to identify the characteristics that make a material suitable for timber gridshell applications, depending on the gridshellβs context, whether in a tropical or international context. This review serves as a necessary reference for architects and engineers when selecting materials for their timber gridshell projects, providing insight into the selection criteria for construction materials and sharing information on the material properties of suitable timber gridshell materials
Azides in the Synthesis of Various Heterocycles
In this review, we focus on some interesting and recent examples of various applications of organic azides such as their intermolecular or intramolecular, under thermal, catalyzed, or noncatalyzed reaction conditions. The aforementioned reactions in the aim to prepare basic five-, six-, organometallic heterocyclic-membered systems and/or their fused analogs. This review article also provides a report on the developed methods describing the synthesis of various heterocycles from organic azides, especially those reported in recent papers (till 2020). At the outset, this review groups the synthetic methods of organic azides into different categories. Secondly, the review deals with the functionality of the azido group in chemical reactions. This is followed by a major section on the following: (1) the synthetic tools of various heterocycles from the corresponding organic azides by one-pot domino reaction; (2) the utility of the chosen catalysts in the chemoselectivity favoring CβH and C-N bonds; (3) one-pot procedures (i.e., Ugi four-component reaction); (4) nucleophilic addition, such as Aza-Michael addition; (5) cycloaddition reactions, such as [3+2] cycloaddition; (6) mixed addition/cyclization/oxygen; and (7) insertion reaction of C-H amination. The review also includes the synthetic procedures of fused heterocycles, such as quinazoline derivatives and organometal heterocycles (i.e., phosphorus-, boron- and aluminum-containing heterocycles). Due to many references that have dealt with the reactions of azides in heterocyclic synthesis (currently more than 32,000), we selected according to generality and timeliness. This is considered a recent review that focuses on selected interesting examples of various heterocycles from the mechanistic aspects of organic azides
ΠΠ΅Π³ΠΎΡΠ½ΡΠΉ ΡΡΠ±Π΅ΡΠΊΡΠ»Π΅Π· Ρ Π±ΠΎΠ»ΡΠ½ΡΡ Ρ Π½ΠΎΡΠΌΠ°Π»ΡΠ½ΠΎΠΉ ΡΠ΅Π½ΡΠ³Π΅Π½ΠΎΠ³ΡΠ°ΠΌΠΌΠΎΠΉ Π»Π΅Π³ΠΊΠΈΡ Π² ΡΠ°ΠΉΠΎΠ½Π΅ Ρ Π²ΡΡΠΎΠΊΠΎΠΉ Π·Π°Π±ΠΎΠ»Π΅Π²Π°Π΅ΠΌΠΎΡΡΡΡ ΡΡΠ±Π΅ΡΠΊΡΠ»Π΅Π·ΠΎΠΌ
The objective was to describe early symptoms of pulmonary tubeculosis (T) when the chest radiograph (CXR) is normal.Seventy patients with culture-positive pulmonary T and normal CXR were selected from a review of 377 consecutive patients with smear- or culture-positive pulmonary T in Babol (Iran) in 1994-2000. Patients with abnormal CXR at the time of the diagnosis were excluded from the analysis.Sixty-eight of the 70 patients (98%) were symptomatic at the time of the diagnosis with cough and sputum production being reported most commonly (97%). Two patients were examined due to contact tracing of a case of infectious pulmonary T, while other 68 patients were tested because of symptoms presence. Sixtyeight patients (97%) had cough longer that 1 month, sputum production was in 63 patients (90%), fever for more than 1 week was in 18 patients (25%), haemoptysis was in 28 patients (40%), weight loss was in 21 patients (30%), hoarseness was in 1 patient (1,4%), dyspnea was in 5 patients (7%). The sputum smears of 5 patients (7 % ) were positive. No-one of patients had underlying diseases. Fifty-six patients (80%) had positive Mantoux skin test. The incidence of culture-positive pulmonary T with a normal chest radiograph was less than 1% in the period from 1988 to 1989 and steadily increased to 10% in the period from 1996 to 1997.The culture-positive pulmonary T with abnormal CXR is not uncommon and the incidence of such presentation is increasing. Patients with this presentation of T are typically symptomatic and/or are detected by contact tracing of infectious pulmonary T cases. The results suggest that patients presenting cough for more than 1 month, a fever longer than 1 week or documented weight loss after known exposure to infectious T should undergo sputum examination for a mycobacterium tuberculosis despite a normal CXR.Π¦Π΅Π»Ρ ΡΠ°Π±ΠΎΡΡ β ΠΎΠΏΠΈΡΠ°ΡΡ ΡΠ°Π½Π½ΠΈΠ΅ ΡΠΈΠΌΠΏΡΠΎΠΌΡ Π»Π΅Π³ΠΎΡΠ½ΠΎΠ³ΠΎ ΡΡΠ±Π΅ΡΠΊΡΠ»Π΅Π·Π° (Π’) ΠΏΡΠΈ Π½ΠΎΡΠΌΠ°Π»ΡΠ½ΠΎΠΉ ΡΠ΅Π½ΡΠ³Π΅Π½ΠΎΠ³ΡΠ°ΠΌΠΌΠ΅ Π»Π΅Π³ΠΊΠΈΡ
(Π ΠΠ).70 Π±ΠΎΠ»ΡΠ½ΡΡ
Ρ ΠΏΠΎΠ΄ΡΠ²Π΅ΡΠΆΠ΄Π΅Π½Π½ΡΠΌ Π±Π°ΠΊΡΠ΅ΡΠΈΠΎΠ»ΠΎΠ³ΠΈΡΠ΅ΡΠΊΠΈ Π»Π΅Π³ΠΎΡΠ½ΡΠΌ Π’ ΠΈ Π½ΠΎΡΠΌΠ°Π»ΡΠ½ΠΎΠΉ Π ΠΠ Π±ΡΠ»ΠΈ ΠΎΡΠΎΠ±ΡΠ°Π½Ρ ΠΈΠ· 377 Ρ ΠΏΠΎΠ΄ΡΠ²Π΅ΡΠΆΠ΄Π΅Π½Π½ΡΠΌ ΠΏΠΎΡΠ΅Π²ΠΎΠΌ ΠΌΠΎΠΊΡΠΎΡΡ ΠΈΠ»ΠΈ Π±Π°ΠΊΡΠ΅ΡΠΈΠΎΡΠΊΠΎΠΏΠΈΠ΅ΠΉ ΠΌΠ°Π·ΠΊΠ° Π»Π΅Π³ΠΎΡΠ½ΡΠΌ Π’ Π² ΠΠ°Π±ΠΎΠ»Π΅ (ΠΡΠ°Π½) Π² 1994-2000 Π³. ΠΠΎΠ»ΡΠ½ΡΠ΅, ΠΈΠΌΠ΅Π²ΡΠΈΠ΅ ΠΏΠ°ΡΠΎΠ»ΠΎΠ³ΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΠΈΠ·ΠΌΠ΅Π½Π΅Π½ΠΈΡ Π½Π° Π ΠΠ Π² ΠΏΠ΅ΡΠΈΠΎΠ΄ ΠΏΠΎΡΡΠ°Π½ΠΎΠ²ΠΊΠΈ Π΄ΠΈΠ°Π³Π½ΠΎΠ·Π°, Π±ΡΠ»ΠΈ ΠΈΡΠΊΠ»ΡΡΠ΅Π½Ρ ΠΈΠ· Π°Π½Π°Π»ΠΈΠ·Π°.68 (98%) ΠΈΠ· 70 Π±ΠΎΠ»ΡΠ½ΡΡ
Π² ΠΏΠ΅ΡΠΈΠΎΠ΄ ΠΏΠΎΡΡΠ°Π½ΠΎΠ²ΠΊΠΈ Π΄ΠΈΠ°Π³Π½ΠΎΠ·Π° ΠΈΠΌΠ΅Π»ΠΈ ΡΠ°Π·Π»ΠΈΡΠ½ΡΠ΅ ΡΠΈΠΌΠΏΡΠΎΠΌΡ Π·Π°Π±ΠΎΠ»Π΅Π²Π°Π½ΠΈΡ, Π½Π°ΠΈΠ±ΠΎΠ»Π΅Π΅ ΡΠ°ΡΡΠΎ ΠΎΡΠΌΠ΅ΡΠ°Π»ΡΡ ΠΊΠ°ΡΠ΅Π»Ρ Ρ ΠΌΠΎΠΊΡΠΎΡΠΎΠΉ (97%). ΠΠ²Π° ΠΏΠ°ΡΠΈΠ΅Π½ΡΠ° ΠΎΠ±ΡΠ»Π΅Π΄ΠΎΠ²Π°Π»ΠΈΡΡ ΠΏΠΎ ΠΏΠΎΠ²ΠΎΠ΄Ρ ΠΊΠΎΠ½ΡΠ°ΠΊΡΠ° Ρ Π±ΠΎΠ»ΡΠ½ΡΠΌΠΈ Π»Π΅Π³ΠΎΡΠ½ΡΠΌ Π’, Π² ΡΠΎ Π²ΡΠ΅ΠΌΡ ΠΊΠ°ΠΊ ΠΎΡΡΠ°Π»ΡΠ½ΡΠ΅ 68 Π±ΡΠ»ΠΈ ΠΎΠ±ΡΠ»Π΅Π΄ΠΎΠ²Π°Π½Ρ Π² ΡΠ²ΡΠ·ΠΈ Ρ ΠΈΠΌΠ΅Π²ΡΠΈΠΌΠΈΡΡ ΠΆΠ°Π»ΠΎΠ±Π°ΠΌΠΈ.68 (97%) Π±ΠΎΠ»ΡΠ½ΡΡ
ΠΆΠ°Π»ΠΎΠ²Π°Π»ΠΈΡΡ Π½Π° ΠΊΠ°ΡΠ΅Π»Ρ Π΄Π»ΠΈΡΠ΅Π»ΡΠ½ΠΎΡΡΡΡ Π±ΠΎΠ»Π΅Π΅ 1 ΠΌΠ΅Ρ, 63 (90%) β Π½Π° ΠΏΡΠΎΠ΄ΡΠΊΡΠΈΡ ΠΌΠΎΠΊΡΠΎΡΡ, 18 (25%) β Π½Π° Π»ΠΈΡ
ΠΎΡΠ°Π΄ΠΊΡ Π±ΠΎΠ»Π΅Π΅ 1 Π½Π΅Π΄, 28 (40%) β Π½Π° ΠΊΡΠΎΠ²ΠΎΡ
Π°ΡΠΊΠ°Π½ΡΠ΅, 21 (30%) β Π½Π° ΡΠ½ΠΈΠΆΠ΅Π½ΠΈΠ΅ ΠΌΠ°ΡΡΡ ΡΠ΅Π»Π°, 1 (1,4%) ΠΏΠ°ΡΠΈΠ΅Π½Ρ ΠΆΠ°Π»ΠΎΠ²Π°Π»ΡΡ Π½Π° Ρ
ΡΠΈΠΏΡ, 5 (7%) β Π½Π° ΠΎΠ΄ΡΡΠΊΡ. Π ΠΌΠ°Π·ΠΊΠ΅ ΠΌΠΎΠΊΡΠΎΡΡ Ρ 5 (7 % ) Π±ΠΎΠ»ΡΠ½ΡΡ
ΠΎΠΏΡΠ΅Π΄Π΅Π»ΡΠ»ΠΈΡΡ ΠΌΠΈΠΊΠΎΠ±Π°ΠΊΡΠ΅ΡΠΈΠΈ ΡΡΠ±Π΅ΡΠΊΡΠ»Π΅Π·Π° (ΠΠΠ’). ΠΠΈΠΊΡΠΎ ΠΈΠ· Π±ΠΎΠ»ΡΠ½ΡΡ
Π½Π΅ ΠΈΠΌΠ΅Π» ΡΠΎΠΏΡΡΡΡΠ²ΡΡΡΠ΅ΠΉ ΠΏΠ°ΡΠΎΠ»ΠΎΠ³ΠΈΠΈ. 56 (80%) ΠΏΠ°ΡΠΈΠ΅Π½ΡΠΎΠ² ΠΈΠΌΠ΅Π»ΠΈ ΠΏΠΎΠ»ΠΎΠΆΠΈΡΠ΅Π»ΡΠ½ΡΡ ΠΏΡΠΎΠ±Ρ ΠΠ°Π½ΡΡ. Π§Π°ΡΡΠΎΡΠ° Π»Π΅Π³ΠΎΡΠ½ΠΎΠ³ΠΎ Π’, ΠΏΠΎΠ΄ΡΠ²Π΅ΡΠΆΠ΄Π΅Π½Π½ΠΎΠ³ΠΎ ΠΏΠΎΡΠ΅Π²ΠΎΠΌ ΠΌΠΎΠΊΡΠΎΡΡ, ΠΏΡΠΈ Π½ΠΎΡΠΌΠ°Π»ΡΠ½ΠΎΠΉ Π ΠΠ ΡΠΎΡΡΠ°Π²ΠΈΠ»Π° ΠΌΠ΅Π½Π΅Π΅ 1% Π² ΠΏΠ΅ΡΠΈΠΎΠ΄ Ρ 1988 ΠΏΠΎ 1989 Π³. ΠΈ Π²ΠΎΠ·ΡΠΎΡΠ»Π° Π΄ΠΎ 10% Π² ΠΏΠ΅ΡΠΈΠΎΠ΄ 1996 ΠΏΠΎ 1997 Π³.ΠΠ΅Π³ΠΎΡΠ½ΡΠΉ Π’, ΠΏΠΎΠ΄ΡΠ²Π΅ΡΠΆΠ΄Π΅Π½Π½ΡΠΉ Π±Π°ΠΊΡΠ΅ΡΠΈΠΎΠ»ΠΎΠ³ΠΈΡΠ΅ΡΠΊΠΈ, ΠΏΡΠΈ Π½ΠΎΡΠΌΠ°Π»ΡΠ½ΠΎΠΉ Π ΠΠ Π²ΡΡΡΠ΅ΡΠ°Π΅ΡΡΡ Π½Π΅ ΡΠ°ΠΊ ΡΠ΅Π΄ΠΊΠΎ, ΠΈ Π΅Π³ΠΎ ΡΠ°ΡΡΠΎΡΠ° Π²ΠΎΠ·ΡΠ°ΡΡΠ°Π΅Ρ. ΠΠΎΠ»ΡΠ½ΡΠ΅ Ρ ΡΠ°ΠΊΠΎΠΉ ΡΠΎΡΠΌΠΎΠΉ Π’ ΠΎΠ±ΡΡΠ½ΠΎ ΠΈΠΌΠ΅ΡΡ ΠΊΠ»ΠΈΠ½ΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΠΏΡΠΎΡΠ²Π»Π΅Π½ΠΈΡ Π·Π°Π±ΠΎΠ»Π΅Π²Π°Π½ΠΈΡ ΠΈ/ΠΈΠ»ΠΈ ΠΊΠΎΠ½ΡΠ°ΠΊΡ Ρ Π±ΠΎΠ»ΡΠ½ΡΠΌΠΈ Π»Π΅Π³ΠΎΡΠ½ΡΠΌ Π’. Π Π΅Π·ΡΠ»ΡΡΠ°ΡΡ ΡΠ²ΠΈΠ΄Π΅ΡΠ΅Π»ΡΡΡΠ²ΡΡΡ, ΡΡΠΎ Ρ ΠΏΠ°ΡΠΈΠ΅Π½ΡΠΎΠ² Ρ ΠΊΠ°ΡΠ»Π΅ΠΌ ΠΏΡΠΎΠ΄ΠΎΠ»ΠΆΠ°ΡΡΠ΅ΠΌΡΡ, 1 ΠΌΠ΅Ρ, Π»ΠΈΡ
ΠΎΡΠ°Π΄ΠΊΠΎΠΉ Π±ΠΎΠ»Π΅Π΅ 1 Π½Π΅Π΄ Π»ΠΈΠ±ΠΎ Π΄ΠΎΠΊΡΠΌΠ΅Π½ΡΠΈΡΠΎΠ²Π°Π½Π½ΠΎΠΉ ΠΏΠΎΡΠ΅ΡΠ΅ΠΉ ΠΌΠ°ΡΡΡ ΡΠ΅Π»Π° ΠΏΠΎΡΠ»Π΅ ΠΈΠ·Π²Π΅ΡΡΠ½ΠΎΠ³ΠΎ ΠΊΠΎΠ½ΡΠ°ΠΊΡΠ° Ρ Π±ΠΎΠ»ΡΠ½ΡΠΌ Π’ Π½Π΅ΠΎΠ±Ρ
ΠΎΠ΄ΠΈΠΌΠΎ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°ΡΡ ΠΌΠΎΠΊΡΠΎΡΡ Π½Π° ΠΠΠ’ Π½Π΅Π·Π°Π²ΠΈΡΠΈΠΌΠΎ ΠΎΡ Π½ΠΎΡΠΌΠ°Π»ΡΠ½ΠΎΠΉ Π ΠΠ
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