Extended AbstractIntroductionEarth's climate is not constant, and environmental changes are the result of changing climate systems. Temperature is one of the basic elements in climate and its change can cause changes in the climate structure of other regions. In atmospheric sciences, the relationship between circulation patterns in distant places and their relationship with the climate of different regions is called teleconnection. Teleconnection indices are known as factors affecting the climate on a large scale, and their effects on precipitation and temperature have been studied. The quasi-biennial OSCILLATION is one of the main components on a global scale in the mantle layer with an average period of 26 months and is considered one of the main components in short-term climate fluctuations. The North Atlantic OSCILLATION indicates the westerly winds over the Atlantic Ocean, indicating the pressure difference between the northern latitudes (Iceland region) and the temperate latitudes (Azores region). The Arctic OSCILLATION is one of the most prominent patterns of sea level pressure changes in high latitudes (20° Northern Hemisphere). Considering the geographical location of Iran and consequently the influence of different weather masses from high latitudes, it is essential to know the factors affecting the climate of this region. The main aim of this study is to determine the role of the simultaneous occurrence of QBO with NAO and AO teleconnections on winter temperature in Iran. MethodologyIn this study, the average monthly temperature data of 100 selected stations in Iran obtained from the Iranian Meteorological Organization (IMO) and Tele-connection indices including QBO, NAO, and AO extracted from the National Oceanic and Atmospheric Organization (NOAA) for a statistical period of 30 years (1988-2019) were investigated. First, all data were sorted by weather seasons (December–January and February). To determine the Pearson correlation coefficient, monthly data as the dependent variable and Tele-connection indices as the independent variable were analyzed in STATISTICA software. The main purpose of this study was to investigate the simultaneous effect of North Atlantic Ocean OSCILLATIONs and Atlantic OSCILLATIONs with Quasi-Biennial OSCILLATION, their positive and negative phases were identified. In this way, for North Atlantic Ocean OSCILLATIONs and Atlantic OSCILLATION numbers less than -0.5 negative phase, numbers between 0.5 and -0.5 neutral phase, and more than 0.5 were considered positive phase. Considering that the range of changes in the cycle of quasi-biennial fluctuations is very large, in order to determine the phases of this cycle, after standardizing the existing values, its positive and negative phases were determined. In the next step, the monthly temperature anomalies for the mentioned months were calculated and their spatial distribution was zoned using the Inverse distance weighting (IDW) method. Results and DiscussionThe results of the research indicate that there is an inverse and significant relationship between the positive QBO phases and February temperature in most of the northern and western regions so, the highest correlation coefficient was calculated at Ilam station as -0.81. There is a significant inverse relationship between NAO and AO teleconnection with temperature in northern and western parts, especially in February and January, so the highest correlation coefficient up to -0.66 with the Arctic OSCILLATION index was observed in Tabriz station. The warmest and coldest winters of the statistical period coincided with the simultaneous occurrence of negative and positive phases of NAO and AO (the very warm winter of 2010 and the very cold winter of 2008). The coincidence of the positive phases of NAO and AO with positive phases of QBO causes normal and subnormal temperatures in most regions of the country, especially in the eastern half. Contrary to this situation, the coincidence of the positive phases of NAO and AO with the negative phases of quasi-biennial fluctuations has no coherent and regular effect on temperature changes. The coincidence of the negative phases of NAO, and AO with the negative phases of QBO causes normal and higher-than-normal temperatures in most of the western half of Iran, especially in the northwest so, the warmest winters of the statistical period have happened in this case (December 2009, January and February 2010). The coincidence of the positive phases of North Atlantic OSCILLATIONs and Arctic OSCILLATIONs with the neutral phases of quasi-biennial OSCILLATIONs provides the conditions for the occurrence of below-normal temperatures in most parts of Iran, especially in the western parts of Iran. If, contrary to this situation, the coincidence of the negative phases of the North Atlantic OSCILLATIONs and the Arctic OSCILLATIONs with the neutral phases of the quasi-biennial OSCILLATIONs does not have a tangible effect on the winter temperature anomaly, and only the possibility of a temperature much warmer than normal seems unlikely. ConclusionThe results showed that the simultaneous occurrence of positive phases of NAO and AO with positive phases of QBO causes normal and lower-than-normal temperatures in half of eastern Iran. The coincidence of the negative phases of NAO and AO with the negative phases of QBO causes higher-than-normal temperatures in most of the western half of Iran. Also, the simultaneous occurrence of neutral phases of QBO with positive phases of NAO and AO causes normal and lower-than-normal temperatures in most regions of Iran except the southern and southeastern parts. If exactly opposite to this situation, the simultaneous occurrence of neutral phases of QBO with negative phases of NAO and AO does not have a noticeable effect on temperature changes, and only the possibility of much hotter than normal temperatures in these conditions seems unlikely.

In the present study, the effects of chemical REACTION on unsteady free convection flow of a viscous, electrically conducting, and incompressible fluid past a moving semi-infinite vertical cylinder with mass transfer and temperature OSCILLATION is studied. The dimensionless governing partial differential equations are solved using an implicit finite-difference method of Crank–Nicolson type, which is stable and convergent. The transient velocity, transient temperature, and transient concentration profiles are studied for various parameters. The local as well as average skin-friction, Nusselt number, and Sherwood number are also analyzed and presented graphically. The results are compared with available computations in the literature, and are found to be in good agreement.

Background and Aim: Culture and specific staining (including Zeil-Nelson and fluorescent methods) are standard measures for the diagnosis of tuberculosis (TB). Because these methods are time-consuming and, sometimes, due to their low accuracy faster and more accurate methods are necessitated. Methods, which can substitute invasive procedures, when obtaining smear samples and culture is not possible, and in addition to being simple and fast, they have an acceptable diagnostic accuracy.The aim of the present study was to verify the diagnostic value of blood Polymerase Chain REACTION (PCR) method in pulmonary TB.Materials and Methods: This case-control study included 64 proven pulmonary TB cases (according to The National TB Protocol) and 28 subjects who were completely healthy. 4.5ml of blood was derived from each participant and then mixed with 0.5ml EDTA. Finally, DNA extraction and PCR testing using SI 6110 primers was performed for all blood samples.Results: Mean age of the cases and controls was 49.8±18.6 and 48.2±18.5, respectively. 49.2% of the cases and 25% of controls were male. Blood PCR in 23 patients with TB was positive, but none of the controls had a positive PCR (thus, sensitivity of 35.7% and specificity of 100%).Conclusion: With regard to specificity of 100% in PCR method (despite its low sensitivity), in conditions where there is no access to an appropriate specimen, a positive blood PCR can obviate invasive procedures and rapid and definitive diagnosis of the disorder and timely treatment of the patient, his life is saved.

Background: The genitourinary system is one of he most common sites of infection in non-pulmonary tuberculosis (TB). The clinical symptoms and radiologic findings of urinary TB are nonspecific. Current diagnostic tests are of low sensitivity and labor-intensive. Therefore, this study was aimed to evaluate diagnostic value of urine PCR in genitourinary tuberculosis (GNTB).Methods: This was a descriptive study on 33 patients with confirmed genitourinary TB. Demographic data, clinical symptoms, laboratory and radiologic findings were collected. For each patient, three consecutive early morning urine specimens were examined by PCR. The diagnostic value of PCR in mycobacterium tuberculosis (MTB) in comparison with standard microbiological methods was assessed.Findings: There were 33 patients with a mean age of 47.27 16.1 years. The most common presenting symptoms were irritative voiding symptoms (51.5%), flanks pain (27.2%), gross hematuria (9%) and suprapubic pain (9%). Laboratory findings in U/A were hematuria (75.8%) and pyuria (60.6%). IVU was abnormal in 61.5% of patients. Most common abnormalities were pyelocalyceal dilation (44%), ureteral stricture and hydroureter (37%) and multiple small calyceal deformities (25%). Of the 33 patients PCR for MTB was positive in 16 cases (48.5%). In patients with abnormal IVU, PCR was positive in 62.5%.Conclusion: A high index of clinical suspicion is necessary for diagnosis of GUTB. PCR is recommended for instant diagnosis and screening before further examination, it cannot be the only method in identification of GUTB.

A five coupled Kaldor-Kalecki economic model with one delay appeared in the literature, in which the periodic solution of the model was verified by numerical analysis. The periodic solution is an important characteristic of the mutual interactions of economic systems. Also, different investment functions may have different delays. The present paper extends the five coupled Kaldor-Kalecki economic model with one delay to a multiple delay system and discusses the existence of periodic OSCILLATION of this multiple delay model. By linearizing the investment functions at the positive equilibrium and analyzing the instability of the positive equilibrium together with the boundedness of the solutions, some sufficient conditions to guarantee the existence of periodic oscillatory solutions for this model are established. Computer simulations are given to illustrate the validity of the theoretical results. The present result is new.

Introduction Simultaneous variations in weather and climate over widely separated regions have long been noted in the meteorological literature. Such variations are commonly referred to as "teleconnections". In the extra-tropics, teleconnections link neighboring regions mainly through the transient behavior of atmospheric planetary-scale waves. One of the most well-known teleconnections is the Arctic OSCILLATION. Arctic OSCILLATION is the leading mode of extratropical circulation from the surface to the lower-level stratosphere in the northern hemisphere. Fluctuations in the Arctic OSCILLATION create a seesaw pattern in which atmospheric pressure at polar and middle latitudes fluctuates between negative and positive phases. For instance, a positive Arctic OSCILLATION phase is accompanied by low pressure over the north Polar Regions and high pressure at the mid-latitudes. These features are reversed in a negative Arctic OSCILLATION phase. The Arctic OSCILLATION trends are highly correlated with atmospheric phenomena such as variability in sea level pressure, storm tracks and precipitation throughout northern hemisphere. Materials and methods The purpose of this study is to examine the impact of the Arctic OSCILLATION on the frequency of days with rainfall event in Iran. For doing so, we used three dataset. 1) The gridded daily precipitation of GPCC in a 1˚ latitude × 1˚ longitude resolution. These data have been extracted for 154 grid points within the political boundary of Iran. Therefore, our initial matrix of daily precipitation have been consisted of 9125 rows, one for each day from March 21, 1988 (Farvardin 1, 1367), to March 20, 2013 (Esfand 29, 1391), and 154 columns, one for each grid point in Iran. 2) The daily Arctic OSCILLATION index from the Climate Prediction Center of the National weather service, NOAA. These data have formed a matrix in 9125×1. 3) The mean daily geopotential height data of 700 hPa level at 2. 5˚ × 2. 5˚ grid resolution from National Center Environmental/ Department of Energy (NCEP-DOE). This matrix is also consisted of 9125 rows, one for each day from March 21, 1988, to March 20, 2013, and 5328 columns, one for each grid point in northern hemisphere. In this study, was used to investigate the impact of the Arctic OSCILLATION on the frequency of rainfall evens. Then, the lag correlation was used to find the highest correlation between the Arctic OSCILLATION and the frequency of the days with rainfall event. Based on this, the frequency of rainfall event was investigated. Finally, the long term mean geopotential height of the 700 hPa level in association with the highest correlation was analyzed. MATLAB software was employed to analyze the data. Results and discussion The statistic and its significant test showed that the relationship between the Arctic OSCILLATION and the frequency of days with rainfall event is significant from October 23-November 21 (Aban) to April 21 – May 21 (Ordibehesht). Then, the obtained results of lag correlation showed simultaneous correlation in the two months of October 23-December 21 (Aban and Azar) and lag time for December 22 – March 20 (winter) and March 21-May 21 (Farvardin and Ordibehesht). Based on the obtained correlation results, the frequency of the days with rainfall event from November to May was investigated during the positive and the negative phases of the Arctic OSCILLATION. The results have indicated that the probability of rainfall events during the positive phase of the Arctic OSCILLATION is the highest. A survey on mean daily geopotential height of 700 hPa level, when the Arctic OSCILLATION is positive, reveals that 700-hPa level is anomalously low over the polar caps and over the region of the Icelandic Low while it is anomalously high over the western half of Africa to southwest Europe. This pattern leads to enhanced pressure gradient over the eastern half of Atlantic and northwest Europe. This 700 hPa level pattern forms a trough over the eastern Mediterranean. Positive vorticity and northerly flow in this area create dynamic conditions to develop low pressure system. When the system is accompanied with other weather conditions can cause rainfall in Iran. In addition to the eastern Mediterranean trough, the sub-tropical high pressure also plays an important role in the rainfall events. Reduction in the zonal range of high pressure at the time of the occurrence of a positive phase of the Arctic OSCILLATION and its retreat from the southern half of Iran and even in the formation a divergent core over north Arab Sea as the most important source of humidity can increase the probability of rainfall event in Iran. Conclusion The results showed that the impact of the Arctic OSCILLATION on the frequency of the days with rainfall event starts from October 23-November 21 (Aban) and continues to April 21 – May 21 (Ordibehsht). The probability of rainfall event during the positive phase of the Arctic OSCILLATION is the highest as well. Synoptic pattern of 700 hPa showed that the positive phase of the Arctic OSCILLATION increase pressure gradient over the eastern half of Atlantic. This pattern provides conditions to develop eastern Mediterranean trough in mid troposphere and low pressure system in low troposphere over the eastern Mediterranean. Decrease of pressure due to the positive phase of Arctic OSCILLATION in mid-latitude affects subtropical high pressure and retreat from southern half of Iran. Its retreat and even formation of a divergent core over north Arab Sea can increase the probability of rainfall events in Iran.

When two bodies slide on each other the asperities are engaged and deformed which causes the dynamic friction. By superposing ‎ultrasonic OSCILLATION to one of the bodies, the friction force is reduced. The experiments show that the friction force may be reduced by ‎about 60 percent depending on material properties and the kinetics of the two bodies. This phenomenon is widely used in metal forming ‎and metal cutting. This phenomenon may be used as a replacement of lubricants in such processes due to its higher efficiency and less ‎pollution effects. In this research an elastic-plastic model for the surface contact is given which is capable of predicting the friction force when ultrasonic ‎vibrations are superimposed to macroscopic motion. The result of this model is compared with that of the experimental values. The ‎differences between these values are shown to be less than 10 percent. The result of the model is also compared with that of the Dong ‎model. The comparison show that the present model ‏‎ has better accuracy of the Dong model.