Serous otitis or otitis media with effusion is one of the common diseases which if left untreated can lead to complications like tympanic membrane atrophy, cholesteatoma formation, behavioural changes, osteonecrosis and sensori - nueral deafness. One of the treatment options for serous otitis is VT placement which has its own complications like ottorhea, perforation and tympano - sclerosis. The rejection time of VT is closely related to the location of the ventilation tube. The complications arising due to VT placement are related to the time period since placement of the tube, social status of the patient, age, personal hygiene including prevention of water entry into the affected ear, etc. This prospective analytical survey with a one year follow up was carried out on children suffering from serous otitis who had been operated (VT placement) during the first half of 1378 at Shahid Rahnemom Hospital. Most of the VT rejections in all age groups occurred about 7-9 months after the operation but no significant difference was observed between the age groups. In the study determining the relation between gender and VT rejection time (P.V= 0.536), it was realized that the maximum number of VT rejections were between 3-6 months after the operation (47.7%) of which 44.3% was seen in boys and 51.9% in girls, thus, no significant difference was observed between the two sexes (P.V=0.691). 33.9% of the total had ottorhea. 35.1 % sclerosis, and 3.4% had a perforation. 27.6% of the patients had no complications. 7.7% of those patients who had a VT in the anterosuperior compartment of the tympanic membrane had a perforation, while only 2.7% of those who had a VT in the postero – interior compartment had a perforation. Age and gender have no effect on VT rejection time. The probability of a VT remaining in place is more in Shepherd type ventilation tubes than Richard type VT. Ventilation tubes placed in the antero - inferior quadrant are rejected earlier than those placed in the antero - superior quadrant. In the population under study, perforation is the least occurring complication in all age groups. There is on significant difference in the complications arising in either gender.      

BACKGROUND AND OBJECTIVES: Treatment of nasolacrimal obstruction is controversial. The purpose of this study was to compare the efficacy of dacryocystorhinostomy (DCR) with catheter intubation or bodkin tube in the treatment of nasolacrimal obstruction.METHODS: This Quasi- experimental study was conducted on patients with lacrimal obstruction who referred to the department of ophthalmology, Babol Medical University from 1999 to 2006. All cases were treated with DCR with intubation or Bodkin tube. Catheter or bodkin tube was drawn out 3 weeks and 4 months, respectively. After treatment all cases were followed at a 3 month interval for one year. Success rates in these two treated groups were compared. FINDINGS: In group DCR with catheter, 79 cases (50 females, 29 males) with the mean age of 34±16 years and in group bodkin tube, 103 cases (50 females, 53 males) with the mean age of 35±0.5 years were treated. The mean age and sex distribution among these two treated groups were equal (p=0.052). The success rate with DCR with catheter intubation was 96.2% and DCR with Bodkin tube was 99.1%. Significant difference was not seen between two groups in treatment failure.CONCLUSION: Dacryocystorhinostomy with catheter intubation or bodkin tube both have the same efficacy for treatment of nasolacrimal obstruction. However the efficacy of dacryocystorhinostomy with Bodkin tube is associated with lower recurrence rate but the difference was not significant.

IntroductionConventional water treatment consist of unit processes include coagulation, flocculation, clarification, filtration and disinfection that goal is removal of turbidity, color and certain bacterial species. In filtration process flocculated substances that have not removed in pervious stage are sediment. Filter media is often silica sand that removal mechanism is complex and consists of mechanical filtration, sedimentation, adsorption, chemical and biological oxidation. The effective removal mechanism in filtration process is adsorption. Two basic factors for adsorption are van der walls force and mass attraction. Sometimes for quantifying and qualifying upgrading of filters, we use other media such as granular activated carbon and anthracite, that in these cases filters have dual media. Activated carbons (ACs) are effective adsorbents in water treatment, because of high removal capability toward soluble and particulate pollutants but slow adsorption kinetics and difficulty for regeneration limited extensive application. Todays, progresses in new technology result in production of other carbon structures such as carbon nano tubes (CNTs). CNTs with mesopore structures and diameter about 2 - 50 nanometer have high potential in organic materials and pathogens removal. Removal of organic matters with carbon nano tubes are in groups such as organic dyes, pharmaceutical, pesticides, phenol, aromatic amines and natural organic matters. Adsorption mechanisms of CNTs are driving including hydrophobic effect, π–π interaction, π–π electron-donor-acceptor (EDA) interaction, electrostatic interaction and hydrogen bonding. Although good potential in organic removal, using in slurry state is a problem that it is necessary to remove CNTs in final treatment. So, if we can capable to deposition these CNTs on media, we can solve this problems. One way to use is deposition of CNTs on silica sand. Although silica sand has adsorption capability, with deposition of CNTs it can remove soluble organic matters. Similar to this coating graphene oxide (GO) was deposited on silica gel that new adsorbent used for mercury and rodamin B removal in batch and continues experiments. One of the shortages in this research was inattention in stability of coating. In other research, pristine single wall carbon nanotube was coated on silica sphere and a method based on non-covalent bonding was represented. The result of this research shows that, bonding has a strong stability.Methods In order to deposition of CNTs on silica sand, physical and chemical processes were used. In physical process heat and in chemical process covalent bonding is effective factors for bonding. Materials that used in this research are carbon nano tube (purchased from nanosov), hydrochloric acid37% (Merck, Germany), nitric acid 65% (Merck, Germany), silica sand (gift from Tehran pars plant) and 3 (triethoxysilyl) - prophylamin (Merck, Germany). Whereas heating may reinforce the bonding between carbon nano tube and silica sand, define temperatures was used to evaluate temperature effects.For evaluating adsorption effects, 4 parameters (pH, adsorbent dose, adsorbate dose and contact time) was investigated. In this study initial pH at neural condition, initial adsorbent in 5-40 gr, initial adsorbate in 2- 12 mg /l and contact time in 10 – 60 minutes was adjusted. For preparation different concentration of TOC a 1000 mg/l stock solution of TOC was prepared and TOC analyzer (model -VCSH, Shimadzu, Japan) for determination of TOC was used.For reversibility of humic acid from surface of new adsorbent adsorption/desorption studies was investigated. So in some series 20 g of engineered nano adsorbent was entered in 200 ml solution of humic acid with initial TOC of 10 mg/l and when adsorption process was equilibrated the adsorption capacity was measured. After that the new adsorbent was poured in 200 ml solution that pH was adjusted from 10-13 with 0.05 and 2 molar NaOH to attain optimum pH. Also desorption time for 10-50 minutes for evaluating optimum time was done. Finally desorption process at 25ºc, 120 rpm and for 5 cycles was repeated.Results and discussionInvestigation method of chemical bonding The method of chemical deposition is establishment of covalent bonding between amin groups of silica and hydroxyl groups of oxidized carbon nano tube. So first, silica sand is hydrolyzed to active OH groups. Then silica sand and amin prophyl is combined to produce NH2 groups and finally oxidized carbon nano tubes and amin groups of silica sand is heated to be resulted –NH groups that is a strong bonding.Stability of MWCNTs coated on sand To investigate stability of MWCNTs coated on sand, ultrasound method was used. Ultrasounds are mechanical waves with high power that disperse in adsorbent to detach CNTs from surface of silica sands. These waves have 40 khz dispersion power frequency. So 6 samples (firstly physical and chemical samples, physical and chemical samples was heated in oven in 100ºc and physical and chemical samples was heated in oven in 200ºc) was putted in the ultrasound bath for 30 min and after that samples was dried and it was seen that physical deposition has not stability and the MWCNTs coated on sand detached from silica sand, but chemical deposition has a strong stability and in samples that was putted it in 200ºc in oven, this stability is very permanent that demonstrate high temperatures has good effects on stability.SEM of MWCNTs coated on sand SEM was used to detect possible morphological changes in pristine and oxidized MWCNTs and also for watching surface of silica sand and MWCNTs coated on silica sand. According to SEM, oxidized MWCNTs with nitric acid, some bundle appear exfoliated and curled and a major alteration of the structural integrity of MWCNTs is observed and length of tube was shortened. On the other side, observation of CNT sand illustrate a non uniform coating of MWCNTs on silica sand that completely differ from surface of silica acid treatment.Investigation potential of CNT sand in removal of organic matter Although MWCNTs potential in removal of organic matter has been demonstrated in some previous research, in this study humic acid was used for index of organic matter to define capability of this adsorbent. So response surface methodology was used for experiment design and initial concentration of adsorbent, adsorbate and contact time was investigated and 20 experiments were defined. According to response from RSM- X/M (mg/g) – with increasing in contact time and decreasing in adsorbent dose the adsorption capacity was increased. Also with increasing in contact time and increasing in adsorbate dose, adsorption capacity is increased that be because of increasing in adsorbate collision with adsorbent. The equilibrium time is about 60 minutes and adsorption capacity at equilibrium time is reached to above 70 mg/g Regeneration of adsorbent To evaluating regeneration of adsorbent the adsorption/desorption process was investigated. Data obtained indicate at pH=10 the regeneration efficiency is about 26.3% and increases up 75.7% at pH=13. Also 30 minutes is the best time for regeneration time and after 5 cycles of regeneration, the adsorption capacity is about 40 mg/g.Conclusion Although silica sand is not applicable to removal of soluble organic matter, but by deposition of carbon nano tubes onto its surface, it can capable to remove this organics. Stability investigations indicate that physical coating has a week bonding between silica sand and carbon nano tubes. In chemical bonding that establish a covalent bonding between silica sand and carbon nano tubes, bonding has a strong stability. Scanning electron microscopy (SEM) on silica surface reveals a non uniform coating of carbon nano tubes on silica sand. Determination of TOC shows in sample with CNT sand, adsorption capacity is higher than to 70% and in sample with raw sand is less than 1%. Regeneration studies indicate that the optimum pH is 13 and optimum time for desorption is 30 minutes. Also after 5 cycles of regeneration the adsorption capacity is about 40 mg/g. These experiment show that the new adsorbent – CNT sand - has a good potential in organic matter removal and regeneration process is simple.

Shifting of surface irrigation to drip system is key tool to reduce water saving. Due to the soil moisture profile variation of the drip irrigation; water distributed of the root zone is not uniform. Moreover, moisture deficit and inefficient fertilizing in drip system due to unavailability in deeper layers of soils is one of the disadvantages of drip system in pistachio orchards with depth root systems. An experiment was carried out by adjusted subsurface drip irrigation (SSDIadj) system in pistachio of Damghan region (Semnan province) in a randomized complete block design with split plot arrangement in three replications for three years. The potassium fertilizer amounts (Fertigation) at three levels (50, 70, and 100% of requirement) were considered as the main plot and the design of conductor tubes of the SSDIadj system in seven levels as sub plots. The irrigation guide tubes were arranged for sand tube irrigation in (control), 40-40-40-40, 40-40- 50-50, 40-40-60-60, 40-40-50-60, 40-40-50-70, and 40-40-50-80. Meteorological data from the nearest meteorological station was collected and analyzed. Yield, water consumption, irrigation water productivity index and growth conditions of ShahPasand pistachio cultivar were determined in different treatments. Data were analyzed using Genstat-12 software and based on the analysis of surplus costs and aerial data, the best treatment including combination of potassium fertilizer and arranged tubes of SSDIadj system was determined. The recommended treatments are including of full irrigation, full potassium fertilizer and guide tubes 40-40-50-70 and or 40-40-50-80. The treatments with stratified conductive tubes in the optimal distribution of water, improving productivity and reducing inefficient consumption water. In addition, there are no restrictions on subsurface irrigation such as root accumulation, root penetration into pores of drippers and as well as accumulation of salts.

In this research, the phenomenon of stress relaxation in unreinforced and reinforced sandy soil with geotextile layer has been studied using a large-scale direct shear test. To investigate the effect of shear speed and soil density on the amount of resistance loss due to stress relaxation, two shear speeds of 0.5 and 5 mm/min and two relative densities of 35% and 60%, respectively, loose and medium density, have been used. All samples have been tested in direct shear test under vertical stress of 100 kPa. The results show that the amount of resistance loss due to stress relaxation depends on the shear stress level, soil density, presence of a geotextile layer in the soil and shear speed. In such a way that by increasing the level of shear stress and shear speed and by decreasing the density of sand and also with the presence of a geotextile layer in soil, the amount of resistance loss due to stress relaxation increases.

The research on tall buildings has been increased due to the demands of suitable spaces. The use of pyramidal architecture in tall structures has several benefits including the ability to lighten the adjacent buildings and prevention from the closure of the view in urban spaces. However, the seismic behavior of pyramidal tube structures requires a closer examination of their design and probable behavior under lateral loads. One of the most important parameters in the pyramidal tapered buildings is the calculation of natural frequency of the vibrating structures (ω). In this study we have proposed new equations and methods for the mentioned calculations which has been compared with software calculations. Many researchers have calculated the free vibration of structures using different methods. One formula to obtain the natural frequency of tube structures is obtained from the fourth-order differential equation (Wang, 1996). An approximate solution in order to analyze the free vibration of tall tube-in-tube buildings have been proposed by different researchers (Lee, 2007; Lee and Bang, 2008; Lee and Tovar, 2014). The modeling of tall building using a beam with varying stiffness and mass subject to the variable axial force caused by simple weight was presented by Mohammadnejad (2015). Free vibration analysis using differential equation has been evaluated by Bozdogan (2009) and Bozdogan (2013). The first natural frequency of tall buildings with a system combined of framed tube, shear core, and belt truss has been calculated under axial force (Kamgar and Rahgozar, 2014; 2015; 2018). A new and simple method of determining the natural frequency of tube structures with tube-in-tube wall has been presented. The novelty of this method refers to the mathematical computation process which is much simpler and shorter. The effect of structure’s weight on the natural frequency of structure has been considered by variable axial force. Tall building is modeled by a beam with variable stiffness and mass along the height of the building. Therefore, the partial differential equation with variable coefficients is used which have been presented by Mohammadnejad and Haji-Kazemi (2018). Furthermore, there is no regular research on the vibrational frequency calculation of pyramidal tube systems, especially by mathematical methods, or a small number of studies have been done most of which have been done on 90-degree structures with tube systems.

Background: In the study, we evaluated efficacy and complications of T-tube application in treatment of intestinal atresia in newborns. Methods: In this randomized clinical trial study, 40 neonates with intestinal atresia were studied. The patients were divided into two comparable groups. After preparation of general conditions for operation, the surgery was applied under general anesthesia. In the first group, primary end-to-end anastomosis with T-tube application and in the second group only primary end-to-end anastomosis was done. Baseline variables (age, sex and birth weight), signs of disease, interval between surgery and beginning of oral nutrition, duration of hospitalization, post operation complications and mortality were compared between the two groups.Results: Age, sex, birth weight, age in operation time, frequency of abdominal distention, bilious vomiting, failure of meconium pass and congenital anomalies were not different significantly. Also interval between surgery and beginning of oral nutrition was not different. In 2 of 20 neonates (10%) in T-tube group post operation complications occurred, but in the other group, 9 neonates of 14 neonates (64.3%) complications were seen after operation (p=0.002). Two neonates (10%) in T-tube group and 8 neonates (40%) in the other group died during post operation follow up (p=0.03). Conclusion: It seems that primary end-to-end anastomosis with T-tube application in neonates with intestinal obstruction decreased complications and mortality rate. More similar studies with larger samples are recommended.