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The development of a bibliographic network to serve the needs of the academic, research, and special libraries in the Arabian Gulf region has long been the dream of professionals in the field. The formulation of Gulf Cooperation Council (GCC), introduction of automation in libraries, and strong networking capabilities of the DOBIS/LIBIS Library Automated System, hold the promise of shared access to library resources. It is hoped that the recent improvements in telecommunications in the region would further advance the chances of development of a bibliographic network. Introduction of Gulfnet, a computer-to-computer communication link among academic institutions in the Gulf region, should contribute to the development of such a network by facilitating interlibrary loan services. In this venture toward greater regional library cooperation the King Fahd University of Petroleum & Minerals (KFUPM) Library can serve as a central node by providing a central database for online cataloging, cooperative acquisition, interlibrary loan, and other resource-sharing activities. There is a need, interalia, for agreement on standards for bibliographic procedures among libraries in the Gulf for achieving a reasonable level of cooperation and resource-sharing. However, the creation of an effective bibliographic network will only be possible with the provision of a legal base by delegating the authority for networking to a region-based organization like GCC and administrative support of individual governments of the Gulf states. [ABSTRACT FROM PUBLISHER]

Introduction & Purpose:Chlorine is the most important matter to water disinfection due to a residual effect. But by formation of by-products could be harmful to consumers’ health ,The researchers decided to use the method or other material. For this reason, in this study ozone used to water disinfection and its performance to disinfect of contaminated water with Escherichia coli was investigated. Methods: E. coli was utilized to contaminated water preparation. Culture and counting methods were performed according to the standard methods and recorded with CFU/ml. Normality of the data was analyzed by using Asmynrf-Kolmogrov test and T-test and ANOVA were used to statistical analysis, too. Results :Theresults showed that the destruction of E. coli increased by increasing of ozone concentration and decreasing of density. Removal of the concentration of 1 mg per liter, compared with a concentration of 5 mg per liter of ozone in the ozone density〖10〗^4و〖10〗^5 CFU / ml is significant(P_value0.05). Conclusion :Ozone due to its oxidizing effect on microorganisms is a good disinfectant properties. The results of this study, ozone can be highly contaminated with E. coli was significantly effective in disinfecting water.

The seaweeds like Sargassum ilicifolum arecan used for animal nutrition. The aim of this study was evaluated the nutritional value of Sargassum ilicifolum as a food supplement in the diet of sheep. In this experiment were five diets containing zero, 10, 20, 30 and 40 percent of the seaweed were used. A completely randomized design was used to this purpose. In this study, the chemical composition of seaweed(Sargassum ilicifolum), DMdegradability,concentration electrolytes parameter from blood,rumen and performance parameters were measured. Treatment effects on feed intake were not significant(p>0.05). Water consumption increased with increase in algae value in deit. In this investigation in situ degradability of dry matter of seaweed in the intervals 0, 4, 8, 16, 24, 48, 72 and 96 hours was studied, amount of part fast degradability (a) and part slow degradability (b) for Sargassum illicifolumwere respectively 42% and33.6%. The effective degradability in outflow rates 2%, 5% and 8% were 49.6%, 45.5% and 44.3%, respectively. Effective treatment wasnot significant on the concentration Na and Cl, but was significant on the concentration K (P

Background: Rhytidectomy poses a significant risk of bleeding. Several studies have reported the safety profile and efficacy of tranexamic acid (TXA), an antifibrinolytic agent, in minimizing perioperative sequelae, particularly hematoma and bleeding., Objectives: The aim of this systematic review was to analyze the effect of TXA administration in facelift surgery, its effect with different routes of administration, and to compare different administration routes in reducing intraoperative blood loss, postoperative edema, and ecchymosis in rhytidectomy., Methods: A systematic literature search was conducted to identify studies that reported on TXA in facelift surgery. The primary outcomes of interest were intraoperative blood loss, time to achieve hemostasis, operation duration, and postoperative hematoma, edema, ecchymosis, drain output, and major and minor complications. Meta-analyses of hematoma, operation duration, drain output, and major and minor complications were performed, and the risk of bias was assessed with ROBINS-I for nonrandomized studies, and Cochrane's RoB 2.0, a tool for randomized controlled trials., Results: In total, 104 articles were included in the initial screening. Out of 388 participants 170 patients were administered TXA, predominantly female (over 91%), with ages from the late 50s to mid-60s. TXA administration varied, with subcutaneous injection being the most common method. The meta-analysis revealed that the pooled prevalence of minor and major hematoma in TXA recipients was remarkably low, with a significant reduction in the risk of minor hematoma (odds ratio [OR] = 0.18, 95% CI 0.05-0.62, P < .001) and no significant difference in major hematoma risk. Interestingly, TXA significantly reduced postoperative drainage compared to the controls (mean difference = -25.59, 95% CI, -30.4--20.77, P < .01). Additionally, neither minor nor major complications were significantly different between the TXA recipients and controls. Specifically, the pooled odds for the incidence of major complications were not significantly different (OR = 1.47, 95% CI, 0.23-9.19, P = .68), and similar results were found for minor complications (OR = 0.59, 95% CI, 0.23-1.48, P = .26)., Conclusions: TXA significantly reduces postoperative drain output and minor hematomas in facelift surgery without increasing major complications. It also reduces edema, ecchymosis, and intraoperative blood loss. However, further studies are required to explore the efficacy of TXA with different dosages and administration routes., (© The Author(s) 2024. Published by Oxford University Press on behalf of The Aesthetic Society. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Background: The response function of imaging systems is regularly considered to improve the qualified maps in various fields. More the accuracy of this function, the higher the quality of the images., Methods: In this study, a distinct analytical relationship between full-width at half-maximum (FWHM) value and detector energy thresholds at distinct tube peak voltage of 100 kV has been addressed in X-ray imaging. The outcomes indicate that the behavior of the function is exponential. The relevant cut-off frequency and summation of point spread function S(PSF) were assessed at large and detailed energy ranges., Results: A compromise must be made between cut-off frequency and FWHM to determine the optimal model. By detailed energy range, the minimum and maximum of S(PSF) values were revealed at 20 keV and 48 keV, respectively, by 2979 and 3073. Although the maximum value of FWHM occurred at the energy of 48 keV by 224 mm, its minimum value was revealed at 62 keV by 217 mm. Generally, FWHM value converged to 220 mm and S(PSF) to 3026 with small fluctuations. Consequently, there is no need to increase the voltage of the X-ray tube after the energy threshold of 20 keV., Conclusion: The proposed FWHM function may be used in designing the setup of the imaging parameters in order to reduce the absorbed dose and obtain the final accurate maps using the related mathematical suggestions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Purpose: The extraction of information from images provided by medical imaging systems may be employed to obtain the specific objectives in the various fields. The quantity of signal to noise ratio (SNR) plays a crucial role in displaying the image details. The higher the SNR value, the more the information is available., Methods: In this study, a new function has been formulated using the appropriate suggestions on convolutional combination of the longitudinal and transverse magnetization components related to the relaxation times of T1 and T2 in MRI, where by introducing the distinct index on the maximum value of this function, the new maps are constructed toward the best SNR. Proposed functions were analytically simulated using Matlab software and evaluated with respect to various relaxation times. This proposed method can be applied to any medical images. For instance, the T 1 - and T 2 -weighted images of the breast indicated in the reference [35] were selected for modelling and construction of the full width at x maximum (FWxM) map at the different values of x-parameter from 0.01 to 0.955 at 0.035 and 0.015 intervals. The range of x-parameter is between zero and one. To determine the maximum value of the derived SNR, these intervals have been first chosen arbitrarily. However, the smaller this interval, the more precise the value of the x-parameter at which the signal to noise is maximum., Results: The results showed that at an index value of x = 0.325, the new map of FWxM (0.325) will be constructed with a maximum derived SNR of 22.7 compared to the SNR values of T 1 - and T 2 -maps by 14.53 and 17.47, respectively., Conclusion: By convolving two orthogonal magnetization vectors, the qualified images with higher new SNR were created, which included the image with the best SNR. In other words, to optimize the adoption of MRI technique and enable the possibility of wider use, an optimal and cost-effective examination has been suggested. Our proposal aims to shorten the MRI examination to further reduce interpretation times while maintaining primary sensitivity., Significance: Our findings may help to quantitatively identify the primary sources of each type of solid and sequential cancer., (© 2023. International Federation for Medical and Biological Engineering.)

Introduction Triple-negative breast cancer (TNBC) is known for its aggressive nature and poor prognosis. Despite its responsiveness to chemotherapy, TNBC presents challenges in terms of survival, recurrence, and mortality rates, particularly in diverse populations. Limited research in the Middle East hampers comprehensive understanding and tailored management. Methods A retrospective study at the King Hussein Medical Center in Jordan between the period 2009 to 2023 explored TNBC patients (n=110) who underwent adjuvant chemotherapy after local excision or modified radical mastectomy (MRM). Data encompassed demographics, clinical variables, and operative details. Statistical analysis employed Wilcoxon and chi-squared tests, examining mortality risks and associations between variables. Results Among 110 TNBC patients (mean age 52), 84% underwent MRM, 16% wide local excision and axillary clearance (WLE&AC). Lymphovascular invasion (LVI) was observed in 41%, linked to higher lymph node positivity. Neoadjuvant therapy preceded MRM in 25% of cases. While 75% had grade III tumors, the prevalence of invasive ductal carcinoma was 85%. Conclusions This study contributes crucial insights into TNBC characteristics and management in Jordan. Despite limitations such as retrospective design and sample size, the findings underscore the need for tailored interventions in TNBC patients, emphasizing the importance of neoadjuvant therapy and vigilant consideration of LVI status in treatment planning. Future longitudinal research should delve into disease progression and treatment outcomes in diverse populations, facilitating optimized TNBC management strategies., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Al Husban et al.)

Purpose: Pavlik harness treatment is the most common treatment in newborns diagnosed with developmental dysplasia of the hip (DDH). The success rates and predictors for failure have been debated over the last decade. In this study, we explored our treatment failure rate and potential prognostic factors that could predict the failure of Pavlik harness (PH) treatment in patients with DDH., Methods: Two hundred and sixty-five patients were treated with PH based on the Graf hip types of classification. Age, gender, first born status, family history, foot deformity, plagiocephaly, breech presentation, hip abduction, hip stability, Graf hip type, Galeazzi sign, bilateralism, and femoral nerve palsy were tested as predictors for failure in multivariate logistic regression mode. Success and failure were determined by the normalization of the hip based on the Graf hip classification., Results: The failure rate of patients treated with Pavlik harness was 16.6% which is within the reported range of failure rate. The mean age of patients who were successfully treated was 6.73 weeks in comparison to 8.84 weeks for those who failed. Age, plagiocephaly, hip instability, Graf classification, and the development of femoral nerve palsy were found to be predictors for failure of PH treatment upon univariate analysis only. However, only the presence of Galeazzi sign, hip instability, high grades of Graf hip classification, and the development of femoral nerve palsy proved to be independent predictors for failed PH treatment upon multivariate logistic regression analysis., Conclusions: Pavlik harness treatment is a successful treatment with an average success of 83.4%. Several independent predictors for failure of PH treatment have been identified. These include a positive Galeazzi sign, a frankly dislocated hip, Graf types III and IV, and the development of femoral nerve palsy., (© 2023. The Author(s) under exclusive licence to SICOT aisbl.)

This study aimed to measure the prevalence and risk factors of diabetic retinopathy (DR) among patients with diabetes mellitus aged 20 to 82 years attending the Faiha Diabetes, Endocrine, and Metabolism Center (FDEMC) in Basrah. A cross-sectional study was conducted at FDEMC, including 1542 participants aged 20 to 82 from January 2019 to December 2019. Both eyes were examined for evidence of DR by a mobile nonmydriatic camera, and statistical analysis was performed to measure the prevalence rates (95% CI) for patients with different characteristics. The mean age of participants was 35.9, with 689 males (44.7%; 95% CI: 42.2-47.2%) and 853 females (55.3%; 95% CI: 52.8-57.8%). The prevalence rate of DR was 30.5% (95% CI: 28.1-32.8%), and 11.27% of cases were proliferative retinopathy. DR significantly increased with age (p-value=0.000), it was higher in females (p-value=0.005), and significantly increased with a longer duration of diabetes (p-value<0.001), hyperglycemia (p-value<0.001), hypertension (p-value=0.004), dyslipidemia (p-value<0.001), nephropathy (p-value<0.001) and smoking (p-value<0.001). There was no statistical association between DR and the type of diabetes or obesity. One-third of the participants in this study had DR. Screening and early detection of DR using a simple tool such as a digital camera should be a priority to improve a person's health status., Competing Interests: The authors declare no conflict of interest., (©2023 JOURNAL of MEDICINE and LIFE.)

Introduction: Healthcare providers are at high risk of becoming infected when taking care of patients who have COVID-19, especially while attending aerosol generating procedures. Protective personal equipment must be used in the correct manner to prevent transmission of the disease. Published protocols on protective personal equipment (PPE) donning and doffing have been issued by disease control agencies., Methods: A questionnaire-based cross-sectional study was designed. An online anonymous questionnaire, which was validated and tested for reliability, focused on PPE related knowledge, donning and doffing practices of healthcare providers across the eastern region of Saudi Arabia., Results: A total of 312 healthcare providers across the eastern region of Saudi Arabia participated in the study, 208 physicians (66.7%) and 104 non-physicians (33.3%). Results indicate poor practice regarding PPE donning (13.8% reported the correct sequence) and PPE doffing (3.5% reported the correct sequence) among participants. In addition, practice and confidence scores regarding other issues with PPE were analyzed. Based on questionnaire responses, being male (T = 2.825; p = 0.008), being a non-physician (T = -2.120; p = 0.014) and being an allied medical professional (F = 5.379; p = 0.003) were significantly associated with higher confidence levels. Also, being a consultant was significantly associated with higher practice scores (F = 4.774; p = 0.008)., Conclusion: The study demonstrates deficiencies among healthcare providers in following the recommended practices for correctly using PPE during the pandemic. Poor practice in PPE donning and doffing necessitates additional educational and training programs focused on infection control practices., Competing Interests: Conflict of interest statement The authors declare no conflict of interest., (©2021 Pacini Editore SRL, Pisa, Italy.)

Introduction: Developmental dysplasia of the hip (DDH) is a common paediatric orthopaedic condition that attracts a substantive amount of controversy. The treatments vary because of the wide spectrum of the condition and the age of children at presentation. Although conservative and surgical treatments exist; it is widely accepted that conservative treatment is the first line of treatment in the first 6 months of life. Several devices have been proposed as the treatment of choice; however, to the best of our knowledge these have not been critically appraised. Therefore, we conducted this review., Methods: A modified Cochrane method was followed with a preplanned detailed research protocol that was developed to guide all aspects of the review. Treatment failure of the devices was chosen as the primary outcome. Secondary outcomes included femoral nerve palsy (FNP), avascular necrosis of the femoral head (AVN), residual dysplasia, skin problems, failure of subsequent surgical treatment, compliance and tolerance issues. Results are reported according to the PRISMA guidelines., Results: A total of 30 studies were included in the review comparing 5 devices (The Pavlik harness, the Von Rosen splint, the Tubingen brace, the Frejka pillow, and the Aberdeen splint). The devices were compared in terms of success rate, AVN rate and residual dysplasia. The von Rosen splint has been shown to be superior to other devices in term of success rates and residual dysplasia (Χ 2 : P < 0.05)., Conclusion: The review findings should be interpreted with caution as there are substantive flaws in the literature and a randomized control trail is warranted to confirm the best device to treat DDH. This is feasible given the magnitude of the problem, the clear diagnostic criteria and the treatment options., (Copyright © 2020 Royal College of Surgeons of Edinburgh (Scottish charity number SC005317) and Royal College of Surgeons in Ireland. Published by Elsevier Ltd. All rights reserved.)

The system matrix (SM) being a main part of statistical image reconstruction algorithms establishes relationship between the object and projection space. The aim was to determine it in a short duration time, towards obtaining the best quality of contrast images. In this study, a new analytical method based on Cavalieri's principle as subdividing common regions has been proposed in which the precision of the amounts of estimated areas was improved by increasing the number of divisions (NOD), and consequently the total SM's time was increased. An important issue is the tradeoff between the NODs and computational time. For this purpose, a Monte Carlo simulated Jaszczak phantom study was performed by the Monte Carlo N-Particle transport code version 5 (MCNP5) in which the tomographic images of resolution and contrast phantoms were reconstructed by maximum likelihood expectation maximization (MLEM) algorithm, and the influence of NODs variations was investigated. The results show that the lowest and best quality have been obtained at the NODs of 0 and 8, respectively and in the optimum case, the SM's total time at NOD of 8 was 925 s, which was much lower than those of the conventional Monte Carlo simulations and experimental test., (© 2020 Published by Elsevier Ltd.)

Methods: A cross-sectional analysis was performed among 1633 asymptomatic adults who underwent colonoscopy examinations during routine health check-ups at the First Affiliated Hospital, College of Medicine, Zhejiang University, between 2015 and 2018., Results: A total of 449 (27.50%) participants were diagnosed with colorectal polyps, and those with colorectal polyps had significantly higher hemoglobin levels than did those without colorectal polyps. Hemoglobin levels were positively associated with the prevalence of colorectal polyps, with rates of 16.43%, 26.20%, 32.17%, and 35.87% among participants with hemoglobin levels in the first, second, third, and fourth quartiles, respectively ( P  for trend < 0.001). Stepwise multiple regression analysis showed that elevated hemoglobin levels independently increased the risk of colorectal polyps (odd ratio = 1.017; 95% confidence interval: 1.008-1.026)., Conclusion: Elevated hemoglobin levels were significantly and independently associated with the prevalence and risk of colorectal polyps in asymptomatic adults., Competing Interests: The authors declare no conflict of interest., (Copyright © 2020 Chao Shen et al.)

Nanoparticles (NPs) indicating a unique potential in bioradiation and nuclear reactor shielding are employed in many fields due to their particular specifications leading improving the mechanical properties as well as pore structure of the concrete-shield. The aim was to introduce a novel coefficient ( ξ ), namely the experimental to theoretical density ratio for mixed-NPs material at various nanoparticles percent concentrations ( ω n a n o ) based on pure mathematical aspects along with the some suitable physical purposes by Monte Carlo method. The change in the mixture density to the change in ω n a n o is always proportional to the ω n a n o value. The density will become maximum at the ω n a n o ∗ in which the physical, morphological and chemical features of NPs along with the amounts of voids in the material have a key role over estimating porosity percentage. The NPs' separation probability as born-cascaded-pairs towards very small radii may be formulated as ξ - ξ - 1 + ω n a n o ∗ + k ' ' | ω n a n o - ω n a n o ∗ | = k ' where k ' and k ' ' are constant values. In conclusion, the theoretical results may be experimentally used in future work for different applications such as designing shield at a nuclear facility.

Inflammatory myofibroblastic tumor (IMT) is a benign lesion that occurs most frequently in the soft tissues and viscera. In the head and neck region, the tumor has been reported to occur in the orbit, tongue, nasopharynx, larynx, and paranasal sinuses and the central nervous system. Despite being a benign lesion, it exhibits infiltrative and destructive behaviours, making histopathological examination necessary to confirm the diagnosis. We report the case of a 38-year-old female presented with a right nasolabial fold mass, which was confirmed histologically to be an IMT. Surgical excision of the mass was achieved through a sublabial approach with an uneventful postoperative period. To the best of our knowledge, this is the first reported case of an IMT in the nasolabial fold.

Objective: The characterization of cancerous tissue and bone metastasis can be distinguished by accurate assessment of accumulated uptake and activity from different radioisotopes. The various parameters and phenomena such as calibration factor, Compton scattering, attenuation and penetration intrinsicallyinfluence calibration equation, and the qualification of images as well., Methods: The camera calibration factor (CF) translates reconstructed count map into absolute activity map, which is determined by both planar and tomographic scans using different phantom geometries. In this study, the CF for radionuclides of Tc-99m and Sm-153 in soft tissue and bone was simulated by the Monte Carlo method, and experimental results were obtained in equivalent tissue and bone phantoms. It may be employed for the simultaneous correction of the scattering and attenuation rays interacted with the camera, leading to corrected counts. Also, the target depth (d) may be estimated by a combination of scattering and photoelectric functions, which we have published before., Results: The calibrated equations for soft tissue phantom for the radionuclides were obtained by RTc = - 10d+ 300 and RSm = -8d + 100, and the relative errors between the simulated and experimental results were 4.5% and 3.1%, respectively. The equations for bone phantom were RTc = -30d + 300 and RSm = - 10d + 100, and the relative errors were 5.4% and 5.6%. The R and d are in terms of cpm/mCi and cm. Besides, the collimators' impact was evaluated on the camera response, and the relevant equations were obtained by the Monte Carlo method. The calibrated equations as a function of various radiation angles on the center of camera's cells without using collimator indicated that both sources have the same quadratic coefficient by -2E-08 and same vertical width from the origin by 8E-05., Conclusion: The presented procedure may help determine the absorbed dose in the target and likewise optimize treatment planning., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Aim: One of the most important microvasculatures' geometrical variables is number of pores per capillary length that can be evaluated using MRI. The transportation of blood from inner to outer parts of the capillary is studied by the pores and the relationship among capillary wall thickness, size and the number of pores is examined., Background: Characterization of capillary space may obtain much valuable information on the performance of tissues as well as the angiogenesis., Methods: To estimate the number of pores, a new pseudo-liquid drop model along with appropriate quantitative physiological purposes has been investigated toward indicating a package of data on the capillary space. This model has utilized the MRI perfusion, diffusion and relaxivity parameters such as cerebral blood volume (CBV), apparent diffusion coefficient (ADC), Δ R 2 and Δ R 2 * values. To verify the model, a special protocol was designed and tested on various regions of eight male Wistar rats., Results: The maximum number of pores per capillary length in the various conditions such as recovery, core, normal-recovery, and normal-core were found to be 183 ± 146, 176 ± 160, 275 ± 166, and 283 ± 143, respectively. This ratio in the normal regions was more than that of the damaged ones. The number of pores increased with increasing mean radius of the capillary and decreasing the thickness of the wall in the capillary space., Conclusion: Determination of the number of capillary pore may most likely help to evaluate angiogenesis in the tissues and treatment planning of abnormal ones.

Objective: One of the major problems associated with parallel hole collimators (PCs) is the trade-off between their resolution and sensitivity. To solve this problem, a novel PC - namely, extended parallel hole collimator (EPC) - was proposed, in which particular trapezoidal denticles were increased upon septa on the side of the detector., Materials and Methods: In this study, an EPC was designed and its performance was compared with that of two PCs, PC35 and PC41, with a hole size of 1.5 mm and hole lengths of 35 and 41 mm, respectively. The Monte Carlo method was used to calculate the important parameters such as resolution, sensitivity, scattering, and penetration ratio. A Jaszczak phantom was also simulated to evaluate the resolution and contrast of tomographic images, which were produced by the EPC6, PC35, and PC41 using the Monte Carlo N-particle version 5 code, and tomographic images were reconstructed by using maximum likelihood expectation maximization algorithm., Results: Sensitivity of the EPC6 was increased by 20.3% in comparison with that of the PC41 at the identical spatial resolution and full-width at tenth of maximum here. Moreover, the penetration and scattering ratio of the EPC6 was 1.2% less than that of the PC41. The simulated phantom images show that the EPC6 increases contrast-resolution and contrast-to-noise ratio compared with those of PC41 and PC35., Conclusion: When compared with PC41 and PC35, EPC6 improved trade-off between resolution and sensitivity, reduced penetrating and scattering ratios, and produced images with higher quality. EPC6 can be used to increase detectability of more details in nuclear medicine images.

Objective: In addition to the trade-off between resolution and sensitivity which is a common problem among all types of parallel hole collimators (PCs), obtained images by high energy PCs (HEPCs) suffer from hole-pattern artifact (HPA) due to further septa thickness. In this study, a new design on the collimator has been proposed to improve the trade-off between resolution and sensitivity and to eliminate the HPA., Methods: A novel PC, namely high energy extended PC (HEEPC), is proposed and is compared to HEPCs. In the new PC, trapezoidal denticles were added upon the septa in the detector side. The performance of the HEEPCs were evaluated and compared to that of HEPCs using a Monte Carlo-N-particle version5 (MCNP5) simulation. The point spread functions (PSF) of HEPCs and HEEPCs were obtained as well as the various parameters such as resolution, sensitivity, scattering, and penetration ratios, and the HPA of the collimators was assessed. Furthermore, a Picker phantom study was performed to examine the effects of the collimators on the quality of planar images., Results: It was found that the HEEPC D with an identical resolution to that of HEPC C increased sensitivity by 34.7%, and it improved the trade-off between resolution and sensitivity as well as to eliminate the HPA. In the picker phantom study, the HEEPC D indicated the hot and cold lesions with the higher contrast, lower noise, and higher contrast to noise ratio (CNR)., Conclusion: Since the HEEPCs modify the shaping of PSFs, they are able to improve the trade-off between the resolution and sensitivity; consequently, planar images can be achieved with higher contrast resolutions. Furthermore, because the HEEPC S reduce the HPA and produce images with a higher CNR, compared to HEPCs, the obtained images by HEEPCs have a higher quality, which can help physicians to provide better diagnosis.

Objective: The goal of the present study was to estimate the number of compartments and the mean apparent diffusion coefficient (ADC) value with the use of the DWI signal curve., Materials and Methods: A useful new mathematic model that includes internal correlation among subcompartments with a distinct number of compartments was proposed. The DWI signal was simulated to estimate the approximate association between the number of subcompartments and the molecular density, with density corresponding to the ratio of the ADC values of the compartments, as determined using the Monte Carlo method., Results: Various factors, such as energy depletion, temperature, intracellular water accumulation, changes in the tortuosity of the extracellular diffusion paths, and changes in cell membrane permeability, have all been implicated as factors contributing to changes in the ADC of water (ADCw); therefore, one may consider them as pseudocompartments in the new model proposed in this study. The lower the coefficient is, the lower the contribution of the compartment to the net signal will be. The results of the simulation indicate that when the number of compartments increases, the signal will become significantly lower, because the gradient factor (i.e., the b value) will increase. In other words, the signal curve is approximately linear at all b values when the number of compartments in which the tissues have been severely damaged is low; however, when the number of compartments is high, the curve will become constant at high b values, and the perfusion parameters will prevail on the diffusion parameters at low b values. Therefore, normal tissues will be investigated when the number of compartments and the ADC values are high and the b values are low, whereas damaged tissues will be evaluated when the number of compartments and the ADC values are low and the b values are high., Conclusion: The present study investigates damaged tissues at high b values for which the effect of eddy currents will also be compensated. These b values will probably be used in functional MRI.

Purpose: Estimation of Compton attenuation and the photoelectric absorption coefficients were explored at various depths., Methods: A new method was proposed for estimating the depth based on the convolution of two exponential functions, namely convolution of scattering and primary functions (CSPF), which the convolved result will conform to the photopeak region of energy spectrum with the variable energy-window widths (EWWs) and a theory on the scattering cross-section. The triple energy-windows (TEW) and extended triple energy-windows scatter correction (ETEW) methods were used to estimate the scattered and primary photons according to the energy spectra at various depths due to a better performance than the other methods in nuclear medicine. For this purpose, the energy spectra were employed, and a distinct phantom along with a technetium-99 m source was simulated by Monte Carlo method., Results: The simulated results indicate that the EWW, used to calculate the scattered and primary counts in terms of the integral operators on the functions, was proportional to the depth as an exponential function. The depth will be calculated by the combination of either TEW or ETEW and proposed method resulting in the distinct energy-window. The EWWs for primary photons were in good agreement with those of scattered photons at the same as depths. The average errors between these windows for both methods TEW, and ETEW were 7.25% and 6.03% at different depths, respectively. The EWW value for functions of scattered and primary photons was reduced by increasing the depth in the CSPF method., Conclusions: This coefficient may be an index for the scattering cross-section.

Objective: Improving signal to noise ratio (SNR) and qualified images by the various methods is very important for detecting the abnormalities at the body organs. Scatter and attenuation of photons by the organs lead to errors in radiopharmaceutical estimation as well as degradation of images. The choice of suitable energy window and the radionuclide have a key role in nuclear medicine which appearing the lowest scatter fraction as well as having a nearly constant linear attenuation coefficient as a function of phantom thickness., Methods: The energy windows of symmetrical window (SW), asymmetric window (ASW), high window (WH) and low window (WL) using Tc-99m and Sm-153 radionuclide with solid water slab phantom (RW3) and Teflon bone phantoms have been compared, and Matlab software and Monte Carlo N-Particle (MCNP4C) code were modified to simulate these methods and obtaining the amounts of FWHM and full width at tenth maximum (FWTM) using line spread functions (LSFs). The experimental data were obtained from the Orbiter Scintron gamma camera., Results: Based on the results of the simulation as well as experimental work, the performance of WH and ASW display of the results, lowest scatter fraction as well as constant linear attenuation coefficient as a function of phantom thickness. WH and ASW were optimal windows in nuclear medicine imaging for Tc-99m in RW3 phantom and Sm-153 in Teflon bone phantom. Attenuation correction was done for WH and ASW optimal windows and for these radionuclides using filtered back projection algorithm. Results of simulation and experimental show that very good agreement between the set of experimental with simulation as well as theoretical values with simulation data were obtained which was nominally less than 7.07 % for Tc-99m and less than 8.00 % for Sm-153. Corrected counts were not affected by the thickness of scattering material. The Simulated results of Line Spread Function (LSF) for Sm-153 and Tc-99m in phantom based on four windows and TEW method were indicated that the FWHM and FWTM values were approximately the same in TEW method and WH and ASW, but the sensitivity at the optimal window was more than that of the other one., Conclusions: The suitable determination of energy window width on the energy spectra can be useful in optimal design to improve efficiency and contrast. It is found that the WH is preferred to the ASW and the ASW is preferred to the SW.

Objective: This study investigates modulation transfer function (MTF) in parallel beam (PB) and fan beam (FB) collimators using the Monte Carlo method with full width at half maximum (FWHM), square and circular-shaped holes, and scatter and penetration (S + P) components., Methods: A regulation similar to the lead-to-air ratio was used for both collimators to estimate output data. The hole pattern was designed to compare FB by PB parameters. The radioactive source in air and in a water phantom placed in front of the collimators was simulated using MCNP5 code., Results: The test results indicated that the square holes in PB (PBs) had better FWHM than did the cylindrical (PBc) holes. In contrast, the cylindrical holes in the FB (FBc) had better FWHM than the square holes. In general, the resolution of FBc was better than that of the PBc in air and scatter mediums. The S + P decreased for all collimators as the distance from the source to the collimator surface (z) increased. The FBc had a lower S + P than FBs, but PBc had a higher S + P than PBs. Of the FB and PB collimators with the identical hole shapes, PBs had a smaller S + P than FBs, and FBc had a smaller S + P than PBc. The MTF value for the FB was greater than for the PB and had increased spatial frequency; the FBc had higher MTF than the FBs and PB collimators., Conclusions: Estimating the FB using PB parameters and diverse hole shapes may be useful in collimator design to improve the resolution and efficiency of SPECT images.

With regard to the different requirements, various collimators are widely employed within nuclear medicine systems in order to evaluate the metabolism of organs as well as improve the contrast of images and better diagnosis. In this study, Fan Beam (FB) and Parallel Beam (PB) collimators in the shapes of round and hexagonal holes have been investigated and compared based on the Geometric Efficiency (G), Geometric Resolution (R(c)), Total Resolution (R(t)), FWHM and Scatter and Penetration (S + P) components using the Monte Carlo simulation. Calculations demonstrated that the G was improved with the increase in the distance between point source and collimator face (z). In contrast, the G was reduced with an increase in the angle of slant hole. In the FB collimator, the R(c) and R(t) were increased when the increase in the hole angle and/or the distance. The simulated results indicated in both collimators with the increase in z, a) the FWHM was increased as well as the peak of the PSF curve was decreased, and b) the S + P amounts decreased, but in the distinct z, the FWHM of the FB collimator is better than that of the PB collimator. It is shown that the results were in agreement with the ADAC company data. Also, Benchmark for measuring ADAC company demonstrated the calculated and simulated amounts of the R(c) and R(t) with round and hexagonal holes shapes had maximum and minimum average relative differences equal to -7.6% for PB and 1% for FB, respectively., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Background: Synechia formation between the middle turbinate (MT) and the lateral nasal wall is a common postoperative complication in endoscopic sinus surgery (ESS) often resulting in revision surgery. To keep the middle meatus open several procedures were described in order to medialise the MT. Long term results of these techniques are missing. The purpose of the study was to evaluate the long term results of fixing the heads of the MT to the septum by a resorbable septal-turbinate-suture (STS)., Material and Methods: 17 patients were included in the retrospective study. All patients underwent ESS with STS because of chronic rhinosinusitis with (8) and without polyps (9). The median follow-up was 81 months (range, 36-105 months). In a total 34 nasal cavities were postoperatively examined by endoscopy. Additionally, rhinomanometry and olfaction test were performed., Results: The MT was found in a central position in between septum and lateral wall in 10 nasal cavities (30 % ), in a more medial position in 24 (70 % ) and none in a lateral position. Only 2 patients presented unilateral synechia to the lateral wall and one unilateral to the septum., Conclusions: Synechia of the MT to the lateral nasal wall in ESS can be effectively avoided by a STS. The long term results showed that STS maintains the MT in a medial position with a free middle meatus without impairing the olfactory function.