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1.
Among many conventional techniques, nuclear techniques have shown to be faster, more reliable, and more effective in detecting explosives. In the present work, neutrons from a 5 Ci Am-Be neutron source being in water tank are captured by elements of soil and landmine (TNT), namely (14)N, H, C, and O. The prompt capture gamma-ray spectrum taken by a NaI (Tl) scintillation detector indicates the characteristic photo peaks of the elements in soil and landmine. In the high-energy region of the gamma-ray spectrum, besides 10.829 MeV of (15)N, single escape (SE) and double escape (DE) peaks are unmistakable photo peaks, which make the detection of concealed explosive possible. The soil has the property of moderating neutrons as well as diffusing the thermal neutron flux. Among many elements in soil, silicon is more abundant and (29)Si emits 10.607 MeV prompt capture gamma-ray, which makes 10.829 MeV detection difficult. The Monte Carlo simulation was used to adjust source-target-detector distances and soil moisture content to yield the best result. Therefore, we applied MCNP4C for configuration very close to reality of a hidden landmine in soil. 相似文献
2.
Vincent Y W Lin David Houlden Allison Bethune Meghan Nolan Farhad Pirouzmand David Rowed Julian M Nedzelski Joseph M Chen 《Otology & neurotology》2006,27(7):1017-1022
To determine whether the percentage calculated by dividing the amplitude of postexcision direct facial nerve stimulus responses (at pontomedullary junction) by the amplitude of distal ipsilateral transcutaneous (stylomastoid region) maximal stimulus responses and response amplitude progression by increasing stimulus intensities have predictive value for determining normal or near-normal (House-Brackmann Grade 1 or 2) immediate postoperative facial nerve function. STUDY DESIGN: Intraoperative recordings of three muscle groups: 1) frontalis, 2) orbicularis oculi, and 3) orbicularis oris. Postexcision direct facial nerve stimulation at the pontomedullary junction and transcutaneous maximal facial nerve stimulation at the ipsilateral stylomastoid region and their associated response amplitudes were recorded. SETTING: Tertiary referral center. PATIENTS AND METHODS: Patients who underwent acoustic neuroma surgery from January 2004 to March 2006 with intraoperative facial nerve monitoring and an intact facial nerve after tumor excision were included. Recordings were available for 38 patients. RESULTS: With a stimulus intensity of 0.3 mA at the root exit zone, there was an 81% positive predictive value in patients that exhibited a compound action potential of greater than 20% of maximum (sensitivity, 81%). This increased to 93% when the compound action potential was greater than 50% of maximum. When the amplitude increase was greater than 5 microV, there was a 77% positive predictive value (sensitivity, 87%). CONCLUSION: The percentage of the response amplitude of direct facial nerve stimulation at the pontomedullary junction when compared with the maximum response amplitude of ipsilateral transcutaneous stimulation at the stylomastoid foramen is a good predictor of normal to near-normal immediate postoperative facial nerve function. Progression of amplitude response also seems to be a good predictor of normal to near-normal immediate postoperative facial nerve function. 相似文献
3.
Farhad Islami MD PhD Rebecca L. Siegel MPH Stacey A. Fedewa PhD MPH Elizabeth M. Ward PhD Ahmedin Jemal DVM PhD 《CA: a cancer journal for clinicians》2017,67(4):273-289
Liver cancer is highly fatal, and death rates in the United States are increasing faster than for any other cancer, having doubled since the mid‐1980s. In 2017, it is estimated that the disease will account for about 41,000 new cancer cases and 29,000 cancer deaths in the United States. In this article, data from the Surveillance, Epidemiology, and End Results (SEER) Program and the National Center for Health Statistics are used to provide an overview of liver cancer incidence, mortality, and survival rates and trends, including data by race/ethnicity and state. The prevalence of major risk factors for liver cancer is also reported based on national survey data from the Centers for Disease Control and Prevention. Despite the improvement in liver cancer survival in recent decades, only 1 in 5 patients survives 5 years after diagnosis. There is substantial disparity in liver cancer death rates by race/ethnicity (from 5.5 per 100,000 in non‐Hispanic whites to 11.9 per 100,000 in American Indians/Alaska Natives) and state (from 3.8 per 100,000 in North Dakota to 9.6 per 100,000 in the District of Columbia) and by race/ethnicity within states. Differences in risk factor prevalence account for much of the observed variation in liver cancer rates. Thus, in contrast to the growing burden, a substantial proportion of liver cancer deaths could be averted, and existing disparities could be dramatically reduced, through the targeted application of existing knowledge in prevention, early detection, and treatment, including improvements in vaccination against hepatitis B virus, screening and treatment for chronic hepatitis C virus infections, maintaining a healthy body weight, access to high‐quality diabetes care, preventing excessive alcohol drinking, and tobacco control, at both the state and national levels. CA Cancer J Clin 2017;67:273–289. © 2017 American Cancer Society. 相似文献
4.
Farhad Jalili Hana Trigui Juan Francisco Guerra Maldonado Sarah Dorner Arash Zamyadi B. Jesse Shapiro Yves Terrat Nathalie Fortin Sbastien Sauv Michle Prvost 《Toxins》2022,14(11)
Health-related concerns about cyanobacteria-laden sludge of drinking water treatment plants (DWTPs) have been raised in the past few years. Microscopic taxonomy, shotgun metagenomic sequencing, and microcystin (MC) measurement were applied to study the fate of cyanobacteria and cyanotoxins after controlled sludge storage (stagnation) in the dark in a full-scale drinking water treatment plant within 7 to 38 days. For four out of eight dates, cyanobacterial cell growth was observed by total taxonomic cell counts during sludge stagnation. The highest observed cell growth was 96% after 16 days of stagnation. Cell growth was dominated by potential MC producers such as Microcystis, Aphanocapsa, Chroococcus, and Dolichospermum. Shotgun metagenomic sequencing unveiled that stagnation stress shifts the cyanobacterial communities from the stress-sensitive Nostocales (e.g., Dolichospermum) order towards less compromised orders and potential MC producers such as Chroococcales (e.g., Microcystis) and Synechococcales (e.g., Synechococcus). The relative increase of cyanotoxin producers presents a health challenge when the supernatant of the stored sludge is recycled to the head of the DWTP or discharged into the source. These findings emphasize the importance of a strategy to manage cyanobacteria-laden sludge and suggest practical approaches should be adopted to control health/environmental impacts of cyanobacteria and cyanotoxins in sludge. 相似文献
5.
Farhad Shaveisi-Zadeh Bahram Nikkho Mohamaad Bagher Khadem Erfan Amir Amiri Ali Azizi Nasrin Mansouri Mitra Tarlan Zahra Rostami-Far 《The Journal of international medical research》2022,50(7)
ObjectiveCOVID-19 has recently emerged as a serious threat to global health. This study examined the laboratory investigations of patients with COVID-19, with an emphasis on liver enzymes.MethodsThis retrospective, single-center study was performed on patients with COVID-19 who were admitted to Imam Reza Hospital, Iran from March 2020 to February 2021. Laboratory tests included a complete blood cell count, white blood cell (WBC) count, neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), lymphocyte/monocyte ratio, and levels of aspartate aminotransferase, alanine aminotransferase (ALT), and alkaline phosphatase. Patient survival was among the outcome measures investigated in association with laboratory findings.ResultsWe enrolled 77 patients with COVID-19 and 63 healthy controls. In comparison with the control group, patients with COVID-19 showed COVID-19 increased ALT, WBC, neutrophils, NLR, and PLR, and decreased platelet counts and lymphocytes.ConclusionAlthough elevated levels of AST, NLR, PLR, and LMR were found in patients with COVID-19, they were not linked to mortality. Given the presence of AST in other tissues, the influence of SARS-CoV-2 on the liver should be interpreted with caution. 相似文献
6.
Zainab Samad Ali Aahil Noorali Awais Farhad Safia Awan Nada Qaiser Qureshi Minaz Mawani Mushyada Ali Laiba Masood Ghufran Adnan Linda K. Shaw Fahim Haider Jafary Salim S. Virani Eric J. Velazquez Zulfiqar Bhutta Gerald S. Bloomfield Javed Tai 《Global Heart》2022,17(1)
Background and Objective:Few data exist on trends in acute myocardial infarction (AMI) patterns spanning recent epidemiological shifts in low middle-income countries (LMICs). To understand temporal disease patterns of AMI characteristics and outcomes between 1988–2018, we used digitized legacy clinical data at a large tertiary care centre in Pakistan.Methods:We reviewed digital health information capture systems maintained across the Aga Khan University Hospital and obtained structured elements to create a master dataset. We included index admissions of patients >18 years that were discharged between January 1, 1988, and December 31, 2018, with a primary discharge diagnosis of AMI (using ICD-9 diagnoses). The outcome evaluated was in-hospital mortality.Clinical characteristics derived from the electronic database were validated against chart review in a random sample of cases (k 0.53–1.00).Results:The final population consisted of 14,601 patients of which 30.6% (n = 4,470) were female, 52.4% (n = 7,651) had ST elevation MI and 47.6% (n = 6,950) had non-ST elevation MI. The median (IQR) age at presentation was 61 (52–70) years. Overall unadjusted in-hospital mortality was 10.3%. Across the time period, increasing trends were noted for the following characteristics: age, proportion of women, prevalence of hypertension, diabetes, proportion with NSTEMI (all ptrend < 0.001). In-hospital mortality rates declined significantly between 1988–1997 and 2008–2018 (13.8% to 9.2%, p < 0.001).Conclusions:The patterns of AMI have changed over the last three decades with a concomitant decline in in-hospital mortality at a tertiary care centre in Pakistan. Clinical digitized data presents a unique opportunity for gaining insights into disease patterns in LMICs. 相似文献
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9.
Farhad Ahmadi Batool Jafari Mehdi Rahimi-Nasrabadi Sahar Ghasemi Kumars Ghanbari 《Toxicology in vitro》2013,27(2):641-650
In this work we proposed a model for in vitro interaction of fenitrothion (FEN) with calf thymus-DNA by combination of multispectroscopic and two dimensional molecular modeling (ONIOM) methods. The circular dichroism results showed that FEN changes the conformation of B-DNA and caused some changes to C-DNA form. The FT-IR results confirmed a partial intercalation between FEN and edges of all base pairs. The competitive fluorescence, using methylene blue as fluorescence probe, in the presence of increasing amounts of FEN, revealed that FEN is able to release the non-intercalated methylene blue from the DNA. The weak chemical shift and peak broadening of 1H NMR spectrum of FEN in the presence of DNA confirmed a non-intercalation mode. The 31P NMR showed that FEN interacts more with DNA via its –NO2 moiety. The ONIOM, based on the hybridization of QM/MM (DFT, 6.31++G (d,p)/UFF) methodology, was also performed by Gaussian 2003 package. The results revealed that the interaction is base sequence dependent, and FEN interacts more with AT base sequences. 相似文献
10.
Vijaya Raj Bhatt Hagop Kantarjian Jorge E. Cortes Farhad Ravandi Gautam Borthakur 《Clinical Lymphoma, Myeloma & Leukemia》2013,13(2):153-158
BackgroundDespite being considered as good prognostic acute myelogenous leukemia (AML), the long-term survival rate in core binding factor (CBF) AML leaves room for substantial improvement.Materials and MethodsWe reviewed relevant English language literature related to treatment of CBF AML available in PubMed. Review also included meeting abstracts.ResultsMulticycle high dose cytarabine in consolidation improves remission duration but larger groups report overall survival in the range of 40% to 50% at 5 years or longer.ConclusionsConcerted effort is needed toward improving outcomes in CBF AML through clinical trials and risk-adapted approach. 相似文献