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The mediastinum forms the central part of the thoracic cavity that is surrounded by pleural space on the two sides, thoracic vertebrae at the posterior, thoracic inlet on the top, and diaphragm at the bottom. It encompasses cardiopulmonary organs and organ systems. Pathological dysfunction or deformity in any part of the mediastinum can have adverse cardiovascular and respqiratory effects. Pectus excavatum and pectus carinatum are the most common congenital chest deformities that are characterized by sternal depression and protuberance of the sternum, respectively. Together, these account for 90% of chest wall deformities. Patients are known to be represented with respiratory distress and cardiovascular dysfunction. The aim of the review article is to present the anatomical and physiological role of the mediastinum in association with important parts of the thoracic cavity and pathological dysfunction of the mediastinum (cardiopulmonary system) due to pectus excavatum and pectus carinatum.

The present study aims to investigate the effect of Sn interlayer on the quality, microstructure and mechanical properties of 7075 T6-AZ31H24 dissimilar joints fabricated by friction stir lap welding. In this regard, various joints were fabricated by changing the interlayer thickness and the number of FSW passes. The microstructure of the joints was studied by optical, scanning and transmission electron microscopes linked to EDS and EBSD detectors. Shear-tensile test was utilized for evaluation of the mechanical properties of the joints. The results showed that the use of 40 μm-thick Sn interlayer was very effective on the improvement of joint quality and joint strength. In this case, the tunneling defect was eliminated and the lap shear fracture load improved by 10% with respect to conventional friction stir lap welding. This was attributed to the facilitated displacement and more proper mixing of dissimilar materials in the nugget due to the lubricating effect of molten tin. Although increase of interlayer thickness showed positive effects on dissimilar material mixing, width of nugget and thickness of mixed region, however, joint strength decreased due to the formation of Mg2Sn intermetallic compound at the out part of the mixed region. Increasing the FSW passes from one to three led to spreading of Mg-Al mixed regions throughout the nugget, thereby the joint strength was deteriorated significantly by formation of various brittle intermetallic compounds (Mg17Al12, Mg2Al3 and Mg2Sn) within the nugget.

The need of intubation and mechanical ventilation is associated with poor prognosis in COVID‐19 patients. Herein, we present two cases of patients with COVID‐19 where intubation and mechanical ventilation failed, and therefore, percutaneous dilatational tracheotomy was performed. The usage of PDT was associated with faster and better recovery in these patients.

Objectives: Increasing macrolide resistance of Mycoplasma pneumoniae strains is becoming a public health concern worldwide. Nevertheless, no comprehensive genomic background of circulating isolates...

A mixture of pre-milled Fe3O4 and Al powder was added to the surface of an aluminum alloy 1050 substrate to obtain hybrid surface nanocomposites using friction stir processing. In situ nano-sized products were formed by the exothermic reaction of Al and Fe3O4. The reaction is triggered by hot working characteristics of the process. The microstructure and crystallographic microtexture transition and grain boundaries evolution of the fabricated nanocomposite were investigated using optical microscopy, X-ray diffraction, field emission scanning electron microscopy, and electron backscattered diffraction analyses. It is illustrated that matrix means grain size decreased in the specimens, which is processed without and with the introduction of the powder mixture to ∼8 and 2 μm, respectively. In addition, high angle grain boundaries showed marked increasing that demonstrates the happening of dynamic restoration phenomenon in the aluminum matrix. Moreover, the fraction of low ΣCSL boundaries showed increasing (remarkably in the presence of hard particles); these boundaries play the main role in dynamic recrystallization. The incorporation of nano-sized products such as Al13Fe4 and Al2O3 in the dynamically recrystallized aluminum matrix produced a pre-dominantly CubeTwin texture component induced by the stirring function of the rotating tool. As a result, the effect of nano-sized products is constrained. Keywords: Friction stir processing, Grain refinement, Microtexture, Grain boundary, Nanocomposites, Aluminum matrix composite

Introduction Malignant cells from different organs after entering through peripheral blood circulation system trap into the first capillary bed in the lungs. Presentation of case A 11-year-old boy with osteosarcoma in right leg was amputated. He had brain and lung metastasis. He underwent chemotherapy and resection of lung nodules with bilateral thoracotomy in two different phases. The patient was discharged in the healthy condition and clear chest radiography. Conclusion The resection of the adenopathy at the mediastina and hilum pulmonis along with assessment of the hormonal receptors is recommended to determine the stage of the diseases.

Introduction The mediastinal space is confined from the top to the thorax inlet, at the bottom with the diaphragm. Presentation of case A female with a right lung tumor with a history of chemotherapy, intubation, mediastinal fixation was performed on the affected side due to inadequate lung expansion, treatment-resistant fistula and intolerance of surgery to the pulmonary fistula. By fixing the mediastinal space on the affected side, right pleural space was drained. Conclusion It is recommended that patients undergoing surgery for chronic empyema due to immunodeficiency and refractory infections, who do not tolerate surgery due to chronic pleural effusion and cavitation due to loculated Empyema develop thoracic surgery, fixation and continued treatment should be performed.

Introduction and importance: Pulmonary Function Tests (PFTS) is an important tool in the assessment of pulmonary pathologies and preoperative evaluation. Case presentation: A 54-year-old man with history of massive pleurisy in the left thorax, treated by placing chest tube and drainage of bloody effusion, was readmitted for epithelioid mesothelioma. He was then presented with pneumothorax due by a refractory bronchial fistula while having a plural catheter. Based on the consultation, the whole-body bone scan was conducted, and findings demonstrated epithelioid mesothelioma (stage 1) with the refractory fistula for which the patient was candidate for thoracic surgery. Decreased lung capacity was seen by Pulmonary Function Testing – PFTS. Clinical discussion The novel PFTS Evaluation Technique was designed to measure the true pulmonary capacities in order to evaluate the pulmonary post-operative tolerance. In this technique the chest tube was placed for 4 weeks until the patient reaches mediastinal fixation then the measurements by PFTS were carried out in two steps. First, using an open chest tube and second, using a clamped chest tube. In both steps, the pulmonary capacities were measured and provided to the pulmonologist for consultation. Conclusion In this case, after acquiring the approval of the specialist depended on PFTS after PFTS Evaluation Technique, the radical extra pleural pneumonectomy surgery was conducted, and the patient was discharged with a good general appearance and treated fistula., Highlights • PFTS is an important tool in the assessment of pulmonary pathologies and for preoperative evaluation. • The patient with pulmonary fistula cannot undergo pneumonectomy surgery. • The PFTS evaluation technique lead to improve the method of evaluating lung capacity tests. • Mediastinal fixation is a suitable approach for patients with refractory fistula and lack of surgical tolerance.

Reactive friction stir processing was used to fabricate in situ hybrid nano-composite. Nano-sized Al2O3 and Al13Fe4 products were formed in the stir zone of rolled AA1050 through the addition of pre-milled Al + Fe3O4 powder mixture. The thermomechanical phenomena associated with the process and addition of active powder mixture provided the occurrence of the aluminothermy reaction. Microstructural investigations showed significant matrix grain refinement; the mean grain size of ~ 3 μm was achieved. The nano-sized reinforcement products prevented grain growth after dynamic recrystallization process by pinning the grain boundaries. The excellent matrix grain refining and formation of in situ hard reinforcements led to the increase of hardness and tensile strength to ~ 56% and 49% over those of the untreated substrate, respectively.

Progress in sustainable manufacturing is a crucial element to minimise negative environmental impacts. The conventional fusion weld process used to join aluminium alloys resulted in coarse grain structure, inevitable defects, and severe joint softening. Friction stir processing (FSP) has the potential to modify the microstructure of materials in joint structure and improve the mechanical properties. In this investigation, the effect of friction stir post–processing was evaluated to study the microstructural characteristics and mechanical properties of GTAW (gas tungsten arc welding) welds in the aluminium 5052 alloy. During FSP, the grains’ dendritic microstructure was destroyed, and the dynamic recrystallisation resulted in a very fine and equiaxed grains structure in the fusion zone. The hardness of the friction-stir-processed welds significantly improved because of microstructure grain refinement. The processed joint demonstrated higher ultimate tensile and yield strength (~275 MPa and 221 MPa, respectively) and superior elongation (31.1%) compared to the unprocessed weld, at the same time, the mechanical strength (yield and ultimate tensile) is similar to that of the base metal.

Combination of mechanical alloying and friction stir processing was used for the fabrication of Al/(Al13Fe4 + Al2O3) nano-composites. Pre-milled hematite + Al powder mixture was introduced into the stir zone generated on 1050 aluminum alloy sheet by friction stir processing. Uniform and active milled powder mixture reacted with plasticized aluminum to produced Al13Fe4 + Al2O3 particles. Al13Fe4 intermetallic showed elliptical shape with a typical size of ~ 100 nm, while nano-sized Al2O3 exhibited irregular floc-shaped particles that formed clusters with the remnant of iron oxide particles in the fine recrystallized aluminum matrix. As the milling time (1-3 h) of the introduced powder mixture increased, the volume fraction of Al13Fe4 + Al2O3 particles increased in the fabricated composite. The hardness and ultimate tensile strength of the fabricated nano-composites varied from 54.5 to 75 HV and 139 to 159 MPa, respectively; these are much higher than those of the friction stir processed base alloy (33 HV and 97 UTS). The highest hardness and strength were achieved for the nano-composite fabricated using the 3-h milled powder mixture; hard nano-sized reaction products and fine recrystallized grains of Al matrix had major and minor roles on enhancing these properties, respectively.

Introduction and importance: Pneumonectomy is commonly associated with cardiopulmonary complications. Pneumonectomy in Pancoast tumor with mediastinal extension and no metastasis could be successful and efficient. Case presentation Herein, we report a successful pneumonectomy of a 54-year-old man with pancoast tumor along with the involvement of mediastinal space including right hilum of the lung, right bronchial, inferior vena cava vein and pericardium. Clinical discussion Based on the bronchoscopy and biopsy, the complete involvement of right bronchial tree was reported and non-small cell carcinoma was diagnosed in pathology. Conclusion To reduce the complications of the surgery, the cardiopulmonary pump machine was used during the operation., Highlights • The role of Pneumonectomy to commonly associated with cardiopulmonary complications. • Pneumonectomy in pancoast tumor with mediastinal extension and no metastasis. • Pneumectomy is with low 5-year survival rate, especially in the case of extended excision. • We report a successful pneumonectomy of a 54-year-old man with pancoast tumor.

Summary The application of ball-milling for reactant powders (Fe2O3+Al) to form in situ nanosized reaction products in the stir zone of 1050 aluminium alloy was examined and the evolution of microstructure, grain boundaries and microtexture of the fabricated Al/(Al13Fe4+Al2O3) nanocomposite was investigated. The mean matrix grain size of the fabricated nanocomposites by the combination of ball milling and friction stir processing were found to be ∼3.2, 3.1 and 2.1 μm for 1, 2 and 3 h milled powder mixtures, respectively. The fraction of high-angle grain boundaries increased markedly in the stir zone indicating the occurrence of dynamic restoration of the aluminium matrix. This was also associated with increasing of the fraction of low ∑CSL boundaries. In addition, the fraction of high-angle grain boundaries increased as the reaction product increased. The developed textures were compared with the most important deformation and recrystallisation texture components of cubic close packed structure. Some of the main texture components formed due to the restoration of aluminium in the stir zone of the material with no powder addition were CubeND {001} , BR {236} and R (or retained S{123} ); these are usually found in the rolled materials. However, the presence of nanosized reaction products in the fabricated nanocomposite changed the texture components to the dominant Goss {011} , P {011} and R{124} textures.

In-situ Al/(Al13Fe4 + Al2O3) hybrid nano-composite was fabricated using reactive friction stir processing (FSP) by introduction of Fe2O3 powder into the stir zone of rolled AA1050 aluminum alloy. Composite reinforcements were produced in-situ by exothermic reaction of Al and Fe2O3 that initiated by hot working characteristics of FSP. However, the existence of intermediate phase (Fe3O4) suggests that the reaction was not completed due to short time of FSP. EBSD results showed that the matrix mean grain size decreased to 8 and 3 μm after FSP without and with introduction of powder, respectively; this was also associated with the marked increase in HAGB. The fabricated nano-composite exhibited superior hardness (45 HV) and ultimate tensile strength (~ 171 MPa) as compared to those of the base and FSPed alloy with no powder addition. Formation of in-situ reinforcements and grain refinement acted as major and minor contributors to enhancement of mechanical properties (hardness and ultimate tensile strength), respectively.

Background: Mycoplasma pneumoniae is a common cause of community-acquired pneumonia (CAP) worldwide, especially among children and debilitated populations. The present study aimed to investigate a loop-mediated isothermal amplification (LAMP) technique for rapid detection of M. pneumoniae in clini-cal specimens collected from patients with pneumonia. Methods: Throat swabs were collected from 110 outpatients who suffered from pneumonia. Throat swab samples were obtained from patients referred to the hospital outpatient clinics of Tehran University hospitals, Iran in 2017. The presence of M. pneumoniae in the clinical specimens was evaluated by LAMP, PCR and culture methods. Sensitivity and specificity of the LAMP and PCR assays were also determined. Results: Out of 110 specimens, LAMP assay detected M. pneumoniae in 35 specimens. Detection limit of the LAMP assay was determined to be 33fg /μL or ~ 40 genome copies/reaction. Moreover, no cross-reaction with genomic DNA from other bacteria was observed. Only 25 specimens were positive by the culture method. The congruence between LAMP assay and culture method was ‘substantial’ (κ=0.77). Specificity and sensitivity of LAMP assay were 88.2%, 100% in compare with culture. However, the con-gruence between LAMP assay and PCR assay was ‘almost perfect’ (κ=0.86). Specificity and sensitivity of LAMP assay were 92.5%, 100% in compare with PCR. Conclusion: Overall, the LAMP assay is a rapid and cost-efficient laboratory test in comparison to other methods including PCR and culture. Therefore, the LAMP method can be applied in identification of M. pneumoniae isolates in respiratory specimens.

The application of friction stir welding (FSW) is growing owing to the omission of difficulties in traditional welding processes. In the current investigation, artificial neural network (ANN) technique was employed to predict the microhardness of AA6061 friction stir welded plates. Specimens were welded employing triangular and tapered cylindrical pins. The effects of thread and conical shoulder of each pin profile on the microhardness of welded zone were studied using tow ANNs through the different distances from weld centerline. It is observed that using conical shoulder tools enhances the quality of welded area. Besides, in both pin profiles threaded pins and conical shoulders increase yield strength and ultimate tensile strength. Mean absolute percentage error (MAPE) for train and test data sets did not exceed 5.4% and 7.48%, respectively. Considering the accurate results and acceptable errors in the models’ responses, the ANN method can be used to economize material and time.

Introduction Mycoplasma pneumoniae is a major cause of atypical community-acquired pneumonia (CAP) with a prevalence range of 15-20% and up to 40% in adults and children, respectively. In Iran, the recorded frequency ranges between 1-6.15%. We aimed to investigate the frequency of M. pneumoniae among patients with atypical pneumonia acquired from the community. Methods Over a period of 5 months between January and June 2017, 520 patients with suspected CAP, who had been to the hospital outpatient clinics of Tehran University, were enrolled in this study. Throat swab specimens were obtained from 110 outpatients who presented with symptoms of atypical pneumonia. M. pneumoniae was identified via culture and biochemical tests, such as fermentation of glucose and arginine, hemolysis, and hemadsorption. For confirmation, PCR was performed to amplify the gene fragment coding for p1 adhesin. Results The major and minor clinical signs of the patients were dyspnea (67.3%) and nausea (15.5%), respectively. Out of 110 specimens, 25 (22.7%) and 29 (26.4%) isolates were identified to be M. pneumoniae via culture and molecular assay, respectively. Comparing the results of the two methods, the PCR showed better sensitivity and rapidity for the detection of M. pneumoniae. There was a high congruence between culture and the PCR assay; kappa level was 'almost perfect' (κ=0.90). Conclusion This is the first report of high frequency of M. pneumoniae in our region. This finding can serve as baseline information for further investigation and confirmation of the potential epidemics of M. pneumoniae pneumonia in our community.

In this study, the effects of tungsten on microstructure and wear performance of Fe-Cr-C claddings were evaluated. In this regard, tungsten inert gas surfacing process was employed to deposit Fe-Cr-C and Fe-Cr-C-W hardfacing alloys on plain carbon steel substrate using preplaced powders. Phase composition, microstructure, and wear behavior of clad layers were investigated using X-ray diffraction analysis, optical and scanning electron microscopy, and reciprocating wear tests, respectively. The claddings were well bonded to the substrate and showed a uniform microstructure. Cr7C3 and WC carbides were detected in the deposited layers. Further investigations indicated that the hardness and wear resistance can be improved by adding tungsten into Fe-Cr-C hardfacing alloys.

Sulfur mustard (SM), with an old manufacturing history still remains as potential threat due to easy production and extensive effects.Increasing studies on SM indicates the interest of researchers to this subject. Almost all human body organs are at risk for complications of SM. This study offers organ-by-organ information on the effects of SM in animals and humans.The data sources were literature reviews since 1919 as well as our studies during the Iraq-Iran war. The search items were SM and its all other nomenclatures in relation to, in vivo, in vitro, humans, animals, eye, ocular, ophthalmic, lungs, pulmonary, skin, cutaneous, organs and systemic. Amongst more than 1890 SM-related articles, 257 more relevant clinicopathologic papers were selected for this review.SM induces a vast range of damages in nearly all organs. Acute SM intoxication warrants immediate approach. Among chronic lesions, delayed keratitis and blindness, bronchiolitis obliterans and respiratory distress, skin pruritus, dryness and cancers are the most commonly observed clinical sequelae.Ocular involvements in a number of patients progress toward a severe, rapid onset form of keratitis. Progressive deterioration of respiratory tract leads to "mustard lung". Skin problems continue as chronic frustrating pruritus on old scars with susceptibility to skin cancers. Due to the multiple acute and chronic morbidities created by SM exposure, uses of multiple drugs by several routes of administrations are warranted.

Objective: In this study, the short term effects of Faradarmani -an Iranian complementary and alternative medicine which is based on the theory of "Consciousness Bond of the Parts"- is examined on the frequency and severity of Asthma attacks. Method: 84 Asthma patients (lottery) with less than one year since diagnosis were randomly selected and divided into two groups of 42 (control and test). Spirometry was taken from both groups. The control group continued their conventional medicine treatment without the intervention of the research group. In addition to routine medicine treatment, the test group was put through Faradarmani treatment. Spirometry was repeated at the end of each month. Length of this research project was three months. Collected data was analyzed after twelve weeks. Results: In the third month of treatment, total number of severe and medium cases had reached 4.8% (1.8-11.3) in test group and 11.9% (1.8-21.9) in control group. (21.3% decline in test, 14.3% decline in control group). The coefficient of decrease in the test group is 1.49. Decline of application of spray in the test group was 3.2 (2.18-4.19) times. Conclusion: Faradarmani had a considerable affect on the decline of the severity and frequency of Asthma attacks on patients.

Friction stir welding (FSW) process is an emerging solid state joining process in which the material that is being welded does not melt and recast. This process uses a non-consumable tool to generate frictional heat in the abutting surfaces. The welding parameters such as tool rotational speed, welding speed, axial force, etc., and tool pin profile play a major role in deciding the weld quality. Friction stir tool plays a major role in friction stir welding process. In this investigation, it is tried to evaluate the effect of tool pin thread and tool shoulder curvature on FSW zone formation in AA6061 aluminium alloy. In this regard, six different tool pin geometries (threadless triangular pin with/without conical shoulder, threaded triangular pin with conical shoulder, threadless square pin with/without conical shoulder, threaded square pin with conical shoulder) are used to fabricate the joints. The formation of FSP zones are analyzed macroscopically. Tensile properties of the joints are evaluated and correlated with the FSP zone formation. Consequently, it is obtained that welding creates a higher quality compared to other tool pin profiles using the square tool with curved shoulder and having threaded pin.

Readers should note that there is a phrase missing in the Acknowledgment Section of this article as published

In the present study, the surface of St52 steel was alloyed with preplaced Fe-Cr-C and Fe-Cr-Nb-C powders by using a tungsten-inert gas (TIG) heat source. The microstructure and phase composition of the alloyed surfaces were investigated using optical microscopy, scanning electron microscopy (SEM) and X-ray diffraction. Microhardness measurements were performed across the alloyed zone. The tribological behaviour of the coatings was evaluated using dry sliding wear tests at room temperature. It was found that the as-deposited coatings consisted of high volume fraction of carbides (Cr7C3, NbC). The Nb free and Nb-contained clad coatings both exhibited an excellent wear resistance compared to 0.22% C carbon steel under dry sliding wear tests. The wear resistance of Nb-contained clad coating was higher than that of the Nb-free clad coating because the hard carbide NbC was distributed in clad coating which increased the wear resistance of clad coating under dry sliding wear test. No cracks were found in the coatings.

Sulfur mustard (SM) has widely been used against the military and civilians during the Iraq-Iran war (1980–1988). It mostly affects the respiratory system. A large historical cohort study was designed to evaluate the pulmonary status of non-military victims in Sardasht, Iran, in comparison with a matched control group 20 years after a single massive exposure. The exposed group was divided into two subgroups of hospitalized and non-hospitalized based on the severity of the injuries indicated by hospitalization a few days following exposure. All participants’ respiratory symptoms and signs were evaluated by internists. Dyspnea (n = 261; P = 93.2%) was the most common symptom. Chronic cough, cough severity, sputum, hemoptysis, dyspnea, pattern of dyspnea, severity of dyspnea (P

Respiratory problems are a major cause of mortality in people with spinal cord injury. More than 2000 veterans with spinal cord injury live in Iran. This study aimed to evaluate the pulmonary function of veterans with spinal cord injury participating in the health-screening program in Tehran-2013. This retrospective descriptive study was conducted by reviewing participants’ medical records. All veterans (368) were male with the mean age of 49.62 ± 6.45 years. The mean time since injury was 27.17 ± 5.03 years; 32 veterans (8.7%) suffered from tetraplegia and 336 (91.3%) were paraplegic; 120 veterans (32.6%) had complete spinal cord injury and 248 had incomplete spinal cord injury (67.4%). Among them, 159 veterans had difficulty coughing; 198 complained of dyspnea and 119 had a history of hospitalization for pneumonia during the last year. It seems that veterans’ pulmonary status in the screening was appropriate indicating the suitability of periodic visits to veterans in the home care program. It is suggested that future studies be conducted simultaneously with health screening programs.

Purpose Statins are known as cholesterol-lowering agents, but have been suggested for the treatment of asthma because of their anti-inflammatory effects. In this study, the potential therapeutic effects of atorvastatin were investigated in asthmatic patients. Methods A total of 62 patients with persistent mild to moderate asthma who presented at asthma clinics of Arak University of Medical Sciences were recruited in a double-blind randomized clinical trial. The asthma clinical control score was assessed based on the standardized Asthma Control Test. Lung volume, i.e., percentage of forced expiratory volume in one second (FEV1%) and percentage of forced vital capacity (FVC%), and peripheral blood eosinophils were also measured. The intervention group was treated with atorvastatin 40 mg per day for 8 weeks, while the control group received a placebo. Asthma controller treatments were not changed. At the beginning and end of the study, serum cholesterol and triglyceride levels were measured to evaluate adherence of the patients to the treatment. Results The asthma control score did not significantly differ between the intervention and control groups (P=0.06). Difference in FEV1%, FVC%, and blood eosinophil count between the intervention and control groups were not statistically significant (P>0.05). The differences in post-treatment cholesterol and low-density lipoprotein cholesterol levels were significant (P Conclusions Our study shows that atorvastatin is not effective in the treatment of persistent mild to moderate asthma.