mohammad eftekhari

The abdomen is the second most common site for sepsis. This potentially life- threatening condition necessitates finding the source and providing prompt medical and/or surgical treatment. This presentation reveals an uncommon cause of intra- abdominal sepsis.A 43-year-old woman presented to the emergency department with abdominal pain, tachycardia, tachypnea, and generalized abdominal tenderness. The evaluation of the laboratory tests showed an elevation in white blood cell count and liver enzymes. Ultrasonography of the liver revealed the presence of hydatid cysts, and the abdomino- pelvic computed tomography scan with contrast displayed multiple pyogenic cysts in her liver, one of which had ruptured into the peritoneum. She underwent surgery, received antimicrobial agents, and was successfully discharged without experiencing any complications.One clinical presentation of a hepatic hydatid cyst could be intra-abdominal sepsis, which requires emergency surgery along with antibiotic and anti-helminthic drugs.

X-rays are routinely utilized for different diagnostic purposes but there is always the risk of an inaccurate diagnosis. This systematic review was designed to investigate whether inverse grayscale mode increased diagnostic accuracy. From inception to February 2022, MEDLINE, Embase, Scopus, Web of Science, and CENTRAL were searched for studies comparing grayscale inversion diagnostic accuracy to the conventional method. Quality assessment was performed using the Quality Assessment of Diagnostic Accuracy Studies version 2 (QUADAS-2) tool. Eighteen studies were included with an overall patient population of 1704. The number of studies investigating each lesion are as follows, lung masses: 13, pneumothoraces: 4, bony lesions: 3, interstitial lung diseases: 3, orthopedic studies: 2, bullous lung disease: 1, pleural effusion: 1, urinary calculus: 1, and large vascular occlusion: 1. Two studies had an overall moderate risk of bias and the remainders had low risk. The combined mode, featuring the conventional mode with the addition of the inverse grayscale, demonstrated better performance or insignificant difference in comparison with the conventional mode in all studies except one, which showed lower sensitivity in detecting pulmonary nodules. Also, meta-analysis of 250 patients in four pulmonary nodule studies showed better area under the ROC curve (AUC) of inverse mode (0.83, 95% CI: 0.75,0.90) in comparison with conventional mode (0.80, 95% CI: 0.72,0.88). Application of inverse mode when using radiography for detection of pulmonary nodules might improve diagnostic accuracy. Also, the inverse/combined mode showed better performance for lesions other than pulmonary nodule in some studies. However, there was insufficient evidence to draw a consistent conclusion.

In present study, an improved severe plastic deformation process named improved tube cyclic expansion extrusion process has been introduced. The idea of this process is taken from the conventional tube cyclic expansion extrusion process, and in this novel process, it is tried to solve some important problems of the conventional process. Improved tube cyclic expansion extrusion process is capable of severe plastic deforming and improving microstructure and mechanical properties of tubular components. Also, this process can be considered for producing relatively long tubes. For this purpose, the improved tube cyclic expansion extrusion process was successfully performed on AZ91 magnesium alloy tubes, up to two passes. Then, the microstructure evolution and the mechanical properties improvement were scrutinized. The results showed that the microstructure and mechanical properties were improved considerably. In this way, after two passes of this process, an ultrafine grained (UFG) microstructure was formed, and the values of ultimate strength (UTS), hardness (Hv) and ductility (EL%) became 3.6, 1.83 and 1.8 times higher, respectively. Also, the comparison of the results of the improved tube cyclic expansion extrusion process with those of the conventional tube cyclic expansion extrusion process indicated that ultimate strength and hardness of the improved process were near to those of the conventional process, but the value of elongation to failure of the improved process is considerably higher than the value of the conventional process. This can be considered as one of the important advantages of the improved process over the conventional process.

 The coronavirus disease 2019 (COVID-19) pandemic has negatively influenced several aspects of medical education (ME).

 We aimed to assess the perception of emergency medicine (EM) residents of COVID-19 impacts on the quality of ME and their wellness.

 This descriptive study was conducted in Tehran, Iran. A questionnaire consisting of 33 questions (5 on hospital experience, 5 on clinical experience, 12 on education, and 11 on wellness) and 1 open-ended question were designed based on the elements found in the existing literature. Face and content validity were determined by an expert panel. The baseline and demographic data were recorded, and the viewpoints of EM residents about different items in the questionnaire (ME and wellness) were evaluated.

 The mean age of residents was 36.4 ± 7.3 years, and 64.8% and 71.8% of the participants were female and married, respectively. Most residents (81.7%) had a previous history of COVID-19 infection (mainly mild and outpatient). We observed that 90.1% of the residents had concerns about transmitting the virus to their families. Most residents agreed on the negative impacts of COVID-19 on the EM residency program and routine clinical care in hospitals. COVID-19 led to a decrease in the diversity of other diseases and bedside learning opportunities. They added that virtual learning and online programs were comfortable and flexible despite some unpleasant outcomes. EM residents experienced anxiety and stress due to the change in physical and social activities and sleep habits during the COVID-19 pandemic.

 EM residents declared that despite the positive attitudes developed after the pandemic, COVID-19 had non-negligible and negative effects on ME. They were also exposed to greater anxiety and worriedness during the mentioned period.

Effective management of radioiodine (RAI)-refractory differentiated thyroid cancer is a challenge due to limited treatment options. Multikinase inhibitor therapy including sorafenib has been an optional treatment in recent years. This study aims to compare the clinical benefit rate, progression free survival, and quality of life between patients who received limited dose of sorafenib (200-400 mg per day) as opposed to the control group.

Twenty-two patients who received sorafenib and twenty-three cases in the control group were studied for two years. Baseline variables were comparable between two subgroups. The results of diagnostic imaging methods were also taken into consideration. Quality of life was measured using the EORTC (European Organization for Research and Treatment of Cancer) quality of life questionnaire.

Based on the RECIST (Response Evaluation Criteria in Solid Tumors) criteria, clinical benefit rate was 77.3% and 47.8% in sorafenib and control subgroups respectively (p value=0.042). The median of progression free survival for the sorafenib subgroup was 24 months and in the control subgroup was 22 months (p value=0.020). In a comparison between two groups regarding their quality of life, all subscales were statistically insignificant between the two groups except for the symptom subscale (p value=0.001).

Low-dose sorafenib maintenance therapy is an effective treatment option in RAI- refractory differentiated thyroid cancer with the main effect of stabilizing the disease. Except for unpleasant but tolerable adverse effects, this treatment has no significant negative influence on the quality of life as far as the physical, role, cognitive, emotional, financial and social functions are concerned.

Large Vessel Vasculitis (LVV) is a chronic inflammatory process that affects the aorta and its main branches. LVV include Takayasu’s Arteritis (TA) and Giant Cell Arteritis (GCA). The diagnosis of TA is made according to clinical criteria and based on the criteria of the American College of Rheumatology (ACR). Monitoring of disease progression and response to treatment is also done using the National Institutes of Health (NIH) criteria. Despite these criteria, diagnosing and evaluating TA activity is a challenging issue and usually occurs in the advanced stages of the disease. The lack of a comprehensive and non-invasive diagnostic method for diagnosing and monitoring the course of TA is obvious. The aim of this study was to evaluate the diagnostic agreement between 2-[18F]FDG PET-CT scan and clinical criteria for assessing TA disease activity. 

Twenty-four known cases of TA, who met the inclusion criteria, were enrolled in this study. The disease-related constitutional signs and symptoms, as well as laboratory and imaging findings were recorded. Patients underwent 2-[18F]FDG PET-CT imaging with standard protocol. Fused PET-CT images were reviewed and, if necessary, images without attenuation correction were visualized as well. Also, 24 control patients of the same age and sex, among the patients who were referred to the imaging center for oncological indications were examined to compare the uptake of different vascular territories.

Out of 15 active patients (according to the NIH criteria), 2-[18F]FDG PET-CT scan was able to correctly identify 14 patients. Also, out of 9 inactive patients, PET scan was negative in eight patients showing that 2-[18F]FDG PET-CT scan could well differentiate between active and inactive status of the disease (p-value < 0.0001). Sensitivity, specificity, positive predictive value and negative predictive value of scan in this study were 93.3%, 88.9%, 93.3% and 88.9%, respectively. The study also showed that the severity of vascular lesion uptake was not affected by immunosuppressive drugs, including corticosteroids and methotrexate. Scan findings were comparable with the results of anatomical imaging in terms of disease activity and the number of vascular lesions with p-value = 0.1 and 0.304, respectively.

In this study we showed that 2-[18F]FDG PET-CT has comparable results with other imaging modalities and NIH criteria; therefore, it can play an important role in assessing the severity of TA, even when patients are on immunosuppressive drugs.

Targeted radionuclide therapy with [177Lu]Lu-prostate-specific membrane antigen (PSMA) has shown promising results for the treatment of castration-resistant prostate cancer (mCRPC). Nevertheless, a proportion of patients do not respond to this therapy. Here, we aimed to evaluate the prognostic significance of the pretreatment pathologic and laboratory factors for the prediction of biochemical response to the first cycle of [177Lu]Lu-PSMA therapy. In this retrospective study, mCRPC patients, referred for [177Lu]Lu-PSMA therapy, were included. We retrieved the data of patients, undergone [177Lu]Lu-PSMA, from March 2019 to March 2021. Multiple baseline pathologic and laboratory parameters were extracted and correlated with the response to the first cycle. The prostate-specific antigen (PSA) level was evaluated six weeks after [177Lu]Lu-PSMA therapy for the biochemical response. Forty-three patients with a mean age of 69.8±10.2 were included. Bone and visceral metastases were present in 81.4% and 14.0% of the patients, respectively. Except for two, all patients had received hormone- and chemotherapy. The mean PSA level was 189.9±259.0 at baseline. Following one cycle of [177Lu]Lu-PSMA, “≥ 10% PSA response” and “≥ 50% PSA response” were seen in 81.4% and 44.2% of the patients, respectively. Patients with higher baseline PSA more frequently had ≥ 10% PSA response (p= 0.004). Also, the reduction in the PSA level correlated with baseline PSA (p=0.013, r=0.375). [177Lu]Lu-PSMA therapy results in the biochemical response in a considerable number of patients after one cycle. In nearly half of patients, PSA declines more than 50%. Higher baseline PSA is correlated with the level of PSA response.

2-[18F]fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography (2-[18F]FDG-PET/CT) is implemented in papillary thyroid cancer (PTC) patients with elevated Thyroglobulin (Tg) and negative Iodine-131 whole-body scan (131I-WBS). Here, we evaluated the impact of TSH stimulation after levothyroxine withdrawal on the detection rate of 2-[18F]FDG-PET/CT. A prospective study was performed on 60 PTC patients, presented with negative 131I-WBS and elevated or unjustifiably high Tg. 2-[18F]FDG-PET/CT was performed in 30 patients while they were on levothyroxine therapy (unstimulated-TSH [uns-TSH]) and after Levothyroxine withdrawal in the other 30 patients (stimulated-TSH [s-TSH]). Results of the two groups were compared using nonparametric tests. Receiver operating characteristic curve was used to find Tg cutoff values for predicting positive scan results. Overall, 2-[18F]FDG-PET/CT was positive in 63.3% of the patients, 80% (24/30) in s-TSH and 46.7% (14/30) in uns-TSH group. The detection rate was higher in s-TSH group (p=0.007). It was still significant in multiple regression analysis (p=0.041). In uns-TSH group, 2-[18F]FDG-PET/CT was more often positive in patients with higher uns-Tg level (p=0.002). An uns-Tg level of ≥19.00 ng/mL predicted positive results with the sensitivity of 0.786 and specificity of 0.750 (area under curve=0.819). Although statistically insignificant (p=0.055), s-Tg was higher in patients with positive 2-[18F]FDG-PET/CT studies in the s-TSH group. No relation was demonstrated between TSH and anti-Tg-antibody levels and 2-[18F]FDG-PET/CT positivity. TSH-stimulation after levothyroxine withdrawal might enhance the detection rate of 2-[18F]FDG-PET/CT in PTC patients. Additionally, 2-[18F]FDG-PET/CT is more often positive in patients with higher Tg levels.

In a mass casualty incident (MCI), when medical resources are overwhelmed by the number and severity of casualties, victims’ triage plays a crucial role in disaster management. This study aimed to assess the difference between two triage methods, Simple Triage and Rapid Treatment (START) and Sacco Triage Method (STM), in an MCI scenario and determine which way leads to more accurate and quick triage results.

 In this simulated prospective cohort study, observers were selected among 2nd-year medical students and newly graduated paramedics and presented with an imaginary disaster scenario. Half of the medical students and paramedics used the START method, and the other half prioritized patients with STM. The triage results accuracy, time to triage, and time to evacuation in the two methods were recorded and analyzed.

One-hundred-fifty observers were divided into four groups. All of them were male, and their mean age was 20.37±1.22 years. The overall accuracy for STM was 89.52% which showed a better and statistically significant performance than the START method (p<0.001). The mean time to triage for each patient in START and STM was 14.29+-2.95 and 16.84+-3.33 seconds, respectively. The mean time to evacuation for each triage method was 4.76+-.98 minutes for START and 5.61+-1.11 minutes for STM. In both STM and START groups, medical students performed better in triage than paramedics (p<0.001 for START and p=0.025 for STM). Medical students were also significantly faster than paramedics in the time to triage and evacuation categories in the STM group (p<0.001).

In conclusion, 2nd-year medical students and newly graduated paramedics performed a more accurate and quicker triage with STM than the START method.

In this study, equal channel angular pressing (ECAP) process with an additional expansion-extrusion stage named expansion-extrusion equal channel angular pressing (EECAP) process is utilized for producing bulk ultrafine grained (UFG) Mg–9Al–1Zn magnesium alloy. In this process, cyclic expansion-extrusion (CEE) and equal channel angular pressing (ECAP) processes are combined. AZ91 magnesium alloy was used for this experiment. An FEM simulation was performed to calculate the compressive hydrostatical stress. Furthermore, microstructural and mechanical properties were investigated. The experimental findings revealed that the ductility of the sample remains almost constant (0.03% drop) while ultimate tensile strength increased about 30%. The average value of microhardness improved from 48 Hv to 65 Hv (35%) and grain size refined from 144 µm to 3.4 µm. Despite the expansion part of the die, there is no need for back pressure. Another advantage of this new method is maintaining ductility while strengthening.

Non-cutaneous malignant melanomas (NCM) are rare malignancies. Due to their nonspecific symptoms, they present later in life. The value of FDG PET/CT in this group of patients is not clear. The aim of this study is to assess the role of FDG PET/CT in the management of NCM and its prognostic implication.

We retrospectively selected twenty-three patients with a diagnosis of NCM evaluated with FDG PET/CT in Shariati hospital between 2019 and 2021. The PET/CT data were reviewed and compared with available conventional imaging findings. Five patients died within five months. The surviving patients were followed within a time interval of 7 to 27.5 months after their PET/CT study, regarding their disease status.

Among 23 patients (8 ocular, 5 sinonasal, 3 pharyngeal, 2 anorectal, 2 vulvovaginal, and 3 unknown primaries), PET/CT was able to detect residual primary disease, assess treatment response, and reveal or exclude metastases. Additional lesions compared to conventional imaging were found in five, while in one with brain metastases PET/CT was unable to detect lesions on MRI.  Thirteen patients had negative PET/CT finding of which 11 (85%) did not have remarkable finding on follow-up. Metastatic disease was recognized in eight. Patients with extensive metastases on FDG PET/CT had a poorer outcome.

Similar to cutaneous melanoma, PET/CT is valuable in the management of NCM patients and is superior to conventional imaging modalities, with the exception of brain metastases. Patients with negative PET/CT findings have a better outcome as opposed to patients with significant positive PET/CT findings.

Primary cardiac osteosarcoma is a very rare malignancy with a high incidence of local recurrence and systemic metastasis, contributing to the poor prognosis. Radiological modalities are commonly used for the evaluation of cardiac masses. 2-[18F]fluoro-2-deoxy-D-glucose ([18F]FDG) positron emission tomography/computed tomography is a valuable whole-body imaging modality in the evaluation of most subtypes of sarcomas. The value of [18F]FDG PET/CT is not well-established in primary cardiac osteosarcoma, and it has rarely been documented in the literature. Here, we report the findings of [18F]FDG PET/CT in a case of a 38-year-old man with primary cardiac osteosarcoma, which clearly demonstrates the recurrent lesions in the myocardium.

In present research, the severe plastic deformation process of hydrostatic tube cyclic extrusion compression was applied through two passes on the aluminum alloy series 5052 tube, and after that the changes of microstructure and mechanical properties of tubes were studied. Hydrostatic tube cyclic extrusion compression process is able to improve the microstructure and the mechanical properties of tubular pieces. Also, this process has the potential to produce relatively long tubes. In this process, owing to the use of pressurized fluid between the tube and die, the friction force is eliminated in these regions. This facilitates the production of longer pieces. Also, in this process, higher hydrostatic compressive stresses are applied on the material causing the delay in the crack formation and propagation. Thus, higher strains can be applied on the material. After two passes of this process, some microstructural and mechanical properties were improved significantly. For instance, the yield strength and the hardness became 1.7, 2.6 and 2.1 times higher, respectively. Also, a loss of ductility of 16℅ was observed. The microstructure analysis revealed that after two passes of the process, the microstructure was changed from a coarse grain microstructure with an average grain size of about 360 μm to an ultrafine cellsubgrain microstructure with average size of about 635 nm.

The concept of sustainability was first crystallized in 1987 in a report by the United Nations Commission on Environment and Development (Brandtland Commission), emphasizing the current human needs and the need for future generations to be able to fulfill their aspirations. Issues such as environmental degradation, the marginalization of significant groups in society, anti-capitalist protests, and the search for innovation and creativity in the public and private sectors have put the issue of sustainability on the agenda of global and organizational problems. the organization should be stable and stablish the sustainability dimension, if they want to live in today's variable environment and roam the evolution path. Many factors including HR can be applied to organization's sustainability analysis, so it is necessary that organizations expand connection between sustainability and human resources management subdivisions.with such a purpose, the available reasearch is mindful to recognise and ranking the components that are effective on human resourse sustainability in the Fars province electronic industries. Fundemental descriptive reasearch method with applicable purpose is applied. The statistical society of reasearch is the Fars privince electronical industries reporter's .purposeful sampling method is used for certification and fusion fuzzy Delphi approach was used for data and hierarchical analysis .This way the effective factors in the sustainable human resourse management implimentation were identufied in social, economical and ecologicalservises. For identification ، screening and ranking the components combined approach and hierarchical technique (AHP) were used .the results showed that the environmental dimension was higher than social and economical dimensions and environmental dimension were the most important one.

In present study, hydrostatic tube cyclic extrusion compression process is introduced as a novel severe plastic deformation process for grain refining and improving mechanical properties of tubular components. Also, this process has the potential to produce relatively long and large tubes. In this process, because of the utilization of pressurized hydraulic fluid between the tube and die, there is nearly no contact friction. This leads to a significant reduction in pressing load. In this research, after applying hydrostatic tube cyclic extrusion compression process on pure copper tube, the microstructure evolution and the mechanical properties improvement were examined. The results denoted that this process was successfully performed on pure copper tube. In this way, the microstructure and mechanical properties were improved significantly. For example, after this process, the ultimate strength of pure copper, the yield strength and the value of hardness became 1.57, 1.85 and 1.86 times higher, respectively, and a low loss of ductility was achieved. Also, after this process, an ultrafine cellular microstructure with average size of about 990 nm were observed. While, the average value of grain size for the unprocessed tube was about 40 μm. The stages of the formation of the observed microstructure are as follows: the creation of a high density of dislocations, the dislocations coalescence with each other and the formation of tangled structures, the formation of ordered arrangements of dislocations and low angle boundaries, the formation of dislocation cells to diminish strain energy, the creation of new dislocations and their movement to boundaries.

Adrenal lesions are commonly observed during 18F-FDG PET/CT studies. Although, most of these lesions are considered benign, an important consideration in oncologic patients is metastasis. Benign lesions, such as adenomas usually present with low 18F-FDG uptake, although overlap with malignant lesions exist and clear SUV cut-off for distinguishing adrenal adenomas has not been established. Different criteria have been proposed to further characterize adrenal lesions, as benign or metastatic. Conventional imaging modalities have additional value when the degree of uptake is equivocal. In this review, we go through some of the common adrenal lesions, as well as discerning features that favor either benign or malignant etiology.

Given the importance and prevalence of trauma patients in the emergency department and the questioning of urinalysis value in predicting intra-abdominal injury, this study was conducted to examine the accuracy of various types of this test.

This diagnostic accuracy study was conducted on adult patients with abdominal trauma. Data gathering were performed retrospectively until sample size completion using a preprepared checklist. Required data, including demographic characteristics, diseases confounding urinalysis, trauma mechanism, important associated injuries, vital signs, etc., were recorded. Accuracy of urinalysis (including macroscopic, microscopic and dipstick) results was compared with findings of patients' enhanced computed tomography (CT) scan findings that was considered as the gold standard, reported by a radiologist.

Totally, 152 multiple trauma patients with the mean age of 37.9 ± 17.7 years were enrolled (90.8% males), of whom 66 (43.42%) patients had hematuria and the CT scan was abnormal in 30 (19.73%) cases. There was a significant correlation between gross hematuria and abnormal CT scan (P < 0.01) as opposed to microscopic or dipstick hematuria (P > 0.05). Based on the findings, the highest sensitivity was for dipstick and microscopic equally and highest specificity, positive predictive value, negative predictive value, positive and negative likelihood ratios, NLR and accuracy were for the gross test.

Microscopic hematuria and dipstick had no significant correlation with abnormal CT scan findings and cannot predict the intra-abdominal injuries in multiple trauma patients. But, macroscopic hematuria could be valuable in this regard.

Pigment villondular synovitis (PVNS) is a rare synovial condition. The nature of this disorder is usually characterized as benign; however, malignant transformation has also been reported. MRI is the diagnostic modality of choice in evaluating this entity, revealing low T1 and T2 weighted signals and blooming artifact on gradient echo sequences.  Three-phase 99mTc-MDP bone scan has been infrequently used to assess these lesions; and a varied pattern on three phase bone scans has been reported. In the present case, we report a case of diffuse type PVNS lesion of the knee, evaluated with three-phase 99mTc-MDP bone scan.  This lesion had a progressive nature. Flow and blood pool images revealed minimal activity in the lesion, with increased radiotracer uptake on delayed images. After surgical resection, the patient’s diagnosis of a PVNS was confirmed. Although, the pattern of PVNS has been characterized as more prominent on vascular and blood pool images, other patterns such as limited arterial and venous perfusion, as observed in our case, is also possible. In addition, SPECT-CT as in this case, provided valuable information regarding the extent of joint involvement.

Management of locally advanced colon cancer metastases is challenging and operation carries an increased risk of morbidity and mortality. The knowledge of exact sites of involvement can aid the surgeon to make a decision regarding complete resection or palliative therapy. PET/CT scan is an advantage in this setting because metabolic alterations often precede the anatomic changes; moreover, it can show unexpected metastases. In addition, PET/CT scan can differentiate adhesions and scar from local invasion of tumor.  We report a rare case of locally advanced colon cancer metastases to mesentery with extension to liver, chest wall and mediastinum depicted on PET/CT scan. The patient was treated with resection of the involved sites. The pathology report confirmed a poorly differentiated adenocarcinoma mainly involving the mesentery with extension to surrounding organs including the liver. Unfortunately, the patient’s condition deteriorated following surgical intervention. Although there is a trend toward complete resection of primary tumor and involved sites in patients with metastatic colon carcinoma to improve overall patient survival by eliminating any residual disease, in more advanced stages of the disease, palliative therapy might be the preferred approach. PET/CT has invaluable complimentary role to improve surgical planning in advanced oncological situations.

Rosai Dorfman disease is a rare form of nonlangerhans cell histiocytosis, presenting with extensive lymphadenopathies. Treatment in most cases of nodal disease, involves close observation; however, extranodal involvement requires a more definitive treatment strategy. Herein, we report a case of extensive Rosai Dorfman disease in a 43-year-old woman presenting for evaluation of treatment response by 18F-FDG PET/CT after frequent relapses and disease progression. In addition to extensive lymphadenothapies in cervical, supraclavicular, superior mediastinum, axillary, abdominopelvic and inguinofemoral regions, the patient had metabolically active bone and subcutaneous lesions which were not previously recognized. Following this 18F-FDG PET/CT study, the patient management was changed to sirolimus and prednisolone. To choose the best treatment option for Rosai Dorfman patients, knowledge of the full extent of disease is important. Compared with conventional imaging, 18F-FDG PET/CT has the advantage of being a whole-body imaging modality and can recognize disease involvement prior to any anatomical changes.

In patients with papillary thyroid cancer (PTC), sentinel lymph node (SLN) radio-guided biopsy is not routinely used for detection of involved neck lymph nodes (NLN); 99mTc-sulfur colloid antimony (99mTc-SC) has been used for this purpose. In this study, besides 99mTc-SC another radiotracer, 99mTc-phytate (99mTc-P) with different doses and injection methods were evaluated. Twenty-two patients, scheduled to undergo thyroidectomy for PTC, were injected for radio-guided SLN biopsy in the morning of operation in 3 groups: intra tumoral injection of about 1 mCi 99mTc-P (group A; n=5); peritumoral injection of less than 3 mCi 99mTc-SC (group B; n=6); and peritumoral injection of 3 to 5 mCi 99mTc-SC with application of massage (group C; n=9). A patient refused to complete the study. No NLN was detected in the pre-operative ultra-sonographic examinations of all patients. Central neck dissection was done for all the participants. The presence of radio guided detected NLN and results of pathology were assessed. In group A and B, no SLN was detected. NLNs were resected in 4 patients in group A and B; 2 of them involved by the tumor. In group C, 6 out of 9 patients (66.7%) had between 1 to 6 SLNs; the procedure failed to detect SLN in a patient in group C with surgically resected reactive NLN (failure rate 1 out of 7). The results underscored the significance of SLN radio guided biopsy in patients with PTC; the radiotracer, dose and method of injection may affect the detection rate.

In this paper, different geometries and arrangements of vortex generators for improving the heat transfer performance of heat sinks have been studied. The effect of different parameters including the inclination angle of vortex generators and the distance between them are also investigated on heat transfer performance of heat sinks. Numerical computations are done based on the finite volume method and they have been validated with available experimental data which were in accurate compatible with each other with RMSE error of less than 6%. According to the obtained outcomes, between rectangular, triangular and symmetrical NACA0012 vortex generator, heat sink with NACA0012 vortex generator has the best thermal performance. On the other hand, heat sink with rectangular vortex generator has the highest fluid flow pressure drop. So, using rectangular vortex generator with heat sink needs a fan with the highest power. Also, the results show that thermal resistance of the heat sink decreases with Reynolds number increase. Also, heat sink pressure drop increases with Re number enhancement. Meanwhile, the pressure drop rate is more sensible in higher Reynolds numbers.