344 research outputs found
Investigating the effects of heavy metals in the waste leachate on the groundwater quality near the landfill (case study: Landfill of Saravan, Rasht)
The main and fundamental scientific reason of scientific community attention to the issue of leachate pollution and its treatment is the possible danger of contamination of water, soil and to some extent air. The reason is that the leachate of landfill in fact is acomplex waste withhigh pollution. Today, in our country, especially in northern areas due to high groundwater levels, the problem of waste disposal and the effects of their leachate entering alluvial groundwater and aquifer contamination downstream based on hydrodynamic thickness in the movement of water is highly regarded andentering a considerable amount of pollution (nitrates, heavy metals, etc.) to underground water sources used for drinking and agriculture, in the long term become a social problem. Saravan landfill is located on 15 km road Rasht of to Tehran is like a black spot in the in the green Hyrcanian forest and receives more than 500 tons of waste daily from provinces cities,particularly Rasht which with no environmental assessment for selected waste disposal, waste disposal is inadequate in Saravan and because of evaporation, fermentation and decomposition of the waste and leachate percolation into the soil and water resources it is associated with high pollution and unleashed leachate river in the heart of nature and based on the ranking of Index criteria it is unacceptable. In this study, sampling was conducted in 2 upstream wells, 3 downstream wells of Saravan landfill then the samples were analyzed by atomic absorption. The results indicate the presence of heavy metals (chromium - lead – zinc -iron - manganese) in water of downstream wells of the landfill compared to upstream wells and the control wells or in other words, it was significantly more than the control and upstream wells and the average concentrations of Pb, Cr, MN, Fe higher than drinking water standards and the mean concentration of MN and Cr in the research water wells was more than standard water for irrigation and agricultural. It shows the leachate percolation into soil and ground water that has been polluted the nearby water of the landfill.Keywords: Groundwater, Landfill, Leachate, Heavy Metals, Sarava
Desmoplastic fibroma of the jaws: A case series and review of literature
Desmoplastic fibroma (DF) is a benign, locally aggressive neoplasm that rarely occurs in the facial skeleton. It usually presents during the first three decades of life. Due to its aggressiveness and high recurrence rate, early diagnosis is imperative, and complete surgical removal of the lesion is the treatment of choice. Herein, we present three cases of DF namely a 2 year-old girl with a mandibular DF, a 9 year-old boy with a maxillary lesion and a 1.5-year old boy with a mandibular DF. Complete clinicopathological information, treatment plan and long-term follow-up of patients are discussed. Histopathologic features of 3 cases revealed non-capsulated spindle cell tumor with fascicular or swirling patterns in incisional biopsy. Immunohistochemical staining was performed to make a definitive diagnosis. Strongly positive nuclear immunoreactivity for β-catenin confirmed the diagnosis of desmoplastic fibroma in 3 cases. Segmental mandibulectomy, partial maxillectomy and hemimandibulectomy were done for the cases. There was no recurrence in our reported cases after 8 and 11 months and 3 years follow up, respectively. It is noteworthy that despite the aggressive nature of DF, young patients often respond well to wide resection treatment. © 2020, Iranian Society of Pathology. All rights reserved
Serum hyaluronate as a non-invasive marker of hepatic fibrosis and inflammation in HBeAg-negative chronic hepatitis B
Background: HBV infection is a serious global heath problem. It is crucial to monitor this disease more closely with a non-invasive marker in clinical trials. We aimed to evaluate the predictive value of serum hyaluronate for the presence of extensive liver fibrosis and inflammation.
Methods: 28 healthy volunteers and 65 patients with HBeAg negative chronic hepatitis B were enrolled. Liver biopsies scored according to Ishak system. Association of serum hyaloronate with liver fibrosis and inflammation were assessed, and cut off points for serum hyaluronate levels were identified by receiver operating characteristics (ROC) curves and their values for prediction of fibrosis and inflammation were assessed.
Results: In patients with CHB serum hyaluronate had the most significant correlation and predictive values for the liver fibrosis and inflammation comparing to the other variables. At the cut off point of 126.4 ngm/ml it could discriminate extensive fibrosis from milder ones with sensitivity of 90.9% and specificity of 98.1%. With the same value it could discriminate extensive inflammation from their milder counterparts with sensitivity of 63.6% and specificity of 92.6%.
Conclusion: Serum hyaluronate was the best predictor of extensive liver fibrosis and inflammation and it could discriminate subgroups of patients with chronic hepatitis B. It could be used as a non-invasive test to monitor these patients more closely with developing anti viral agents in clinical trials
Assessment of Service Quality at Central Library of Management and Planning Organization (MPO), Iran
This study examines the quality of services at Iran’s Central Library of Management and Planning Organization (MPO) from the viewpoint of itsusers. The research was conducted in two phases: First, the library and its services were compared to the Standards for Special Libraries published bythe National Library of Iran (NLI). The library was found to meet most of the standards. Second, the quality of service provided by the library atexpected and observed levels was examined from the viewpoint of organizational and non-organizational members using a modified version ofthe SERVQUAL questionnaire. Findings showed a significant was difference between two (expected and observed) levels, meaning that users’expectations have not been met. The most significant difference related to “appropriate collection of information resources”. The results also showedthere was no significant difference between organizational and non-organizational users’ opinions about the quality of services. Findingsalso showed that “relevant information services” was the priority of user groups-users emphasized the need for timely and accurate information.There was a correlation between the rate at which the library conformed to the national standards and users’ expectations of quality
A suggested prototype for assessing bone health
Background- Osteoporosis is becoming a health concern worldwide. Considering the fact that prevention plays an important role in reducing the burden of this silent disease and in view of the limited resources available, many countries have adopted certain programs to fight osteoporosis through shifting their attention towards at-risk individuals. The Iranian Multicenter Osteoporosis Study (IMOS) is one of these programs. The program aims to assess bone health and the prevalence of vitamin D deficiency in different parts of Iran with various altitudes, latitudes and lifestyle habits in a way that the results could be generalized to the country. Method- The present article presents the protocol used in the third phase of the study. It was designed based on the experiences gathered in the previous phases to overcome the shortcomings particularly subject loss. The questionnaire applied in this study was developed based on a thorough literature review of the risk factors and secondary causes of osteoporosis and was approved by an expert panel. It should be added that while the majority of the existing studies aim to study a certain aspect of osteoporosis, the present protocol provides the information needed for policy makers and researchers to study different osteoporosis-related issues. Conclusion- The authors believe the protocol, to be implemented with small modifications, can help policymakers in different parts of the world, particularly developing countries, gather accurate information on different aspects of bone health at the national level. © 2015, Academy of Medical Sciences of I.R. Iran. All rights reserved
Performance Improvement and Two-Phase Flow Study of a Piezoelectric Micropump with Tesla Nozzle-Diffuser Microvalves
The Present article aims to design a piezoelectric micropump using a combinational form of microvalves with sufficient diodicity in low-pressure gradients. The goal is to enhance the capability of piezoelectric micropumps with Tesla-type valves in order to deliver insulin. Tesla-type valves are in the category of passive valves which have sufficient diodicity in case of high-pressure gradients. However, low mass flow rates are often required in drug delivery devices. In this paper, the performance of MT135 Tesla-type valve in low pressure-gradient flows has been investigated and a range of reunion angles, which have not been studied before has been examined by numerical solutions. Inspired by nozzle-diffuser valve types, some changes in the bypass path of the microvalve have been exerted to boost the diodicity of the valve in low-pressure conditions that resulted in 9.97% increase of diodicity. At last but not least, the velocity gradients in single-phase flow of water has been attained and performance of micropump toward other kinds of flows has been investigated by a volume of fluid (VOF) model including water as the primary phase and air as the secondary one. To complete the analysis, a VOF model consisting of an arbitrary kind of Casson fluid with the primary phase of water was reached and discussed
Out-of-plane behavior of one-way spanning unreinforced masonry walls
An analytical model is developed to describe the out-of-plane response of one-way spanning unreinforced masonry (URM) walls by investigating the effects of various parameters. Horizontal crack height, masonry compressive strength, and diaphragm support stiffness properties are assumed as variables, and sensitivity analyses are performed to study the influence of these parameters on the cracked wall characteristic behavior. The parametric studies show that crack height significantly influences wall stability by affecting both the instability displacement and the wall lateral resistance. The reduction in cracked wall lateral resistance and in the instability displacement caused by finite masonry compressive strength is shown to be significantly amplified by the applied overburden. A study using the typical configuration of flexible diaphragms and URM walls indicates that the wall top support flexibility does not significantly influence cracked wall out-of-plane response. An existing simplified wall behavioral model is improved, and a procedure is proposed for calculation of the wall out-of-plane response envelope.Hossein Derakhshan; Michael C. Griffith; and Jason M. Ingha
CXCL-10: a new candidate for melanoma therapy?
Background: Melanoma is a malignancy that stems from melanocytes and is defined as the most dangerous skin malignancy in terms of metastasis and mortality rates. CXC motif chemokine 10 (CXCL10), also known as interferon gamma-induced protein-10 (IP-10), is a small cytokine-like protein secreted by a wide variety of cell types. CXCL10 is a ligand of the CXC chemokine receptor-3 (CXCR3) and is predominantly expressed by T helper cells (Th cells), cytotoxic T lymphocytes (CTLs), dendritic cells, macrophages, natural killer cells (NKs), as well as some epithelial and cancer cells. Similar to other chemokines, CXCL10 plays a role in immunomodulation, inflammation, hematopoiesis, chemotaxis and leukocyte trafficking. Conclusions: Recent studies indicate that the CXCL10/CXCR3 axis may act as a double-edged sword in terms of pro- and anti-cancer activities in a variety of tissues and cells, especially in melanoma cells and their microenvironments. Most of these activities arise from the CXCR3 splice variants CXCR3-A, CXCR3-B and CXCR3-Alt. In this review, we discuss the pro- and anti-cancer properties of CXCL10 in various types of tissues and cells, particularly melanoma cells, including its potential as a therapeutic target. © 2020, International Society for Cellular Oncology
Ionic Liquid 3-Methyl-1-sulphonic Acid Imidazolium Chloride {[Msim]Cl}: A Highly Efficient, Mild and Green Catalyst for the Synthesis of β-Acetamido Ketones
Brønstedacidic ionic liquid 3-methyl-1-sulphonic acid imidazolium chloride {[Msim]Cl} is utilized as a highly efficient, inexpensive, mild and green catalyst for the synthesis of β-acetamido ketones by the one-pot multi-component coupling between acetophenones, arylaldehydes, acetonitrile and acetyl chloride at room temperature. Under these conditions, the title compounds are produced in high to excellent yields and in relatively short reaction times. In addition, this method is superior to reported methods, for the synthesis of β-acetamido ketones and is applicable for the synthesis of tris(β-acetamido ketone).Keyword: 3-Methyl-1-sulphonic acid imidazolium chloride {[Msim]Cl}, β-acetamido ketone, Brønsted acidic catalyst, ionic liquid, one-pot multi-component reaction, acetophenon
Emergency tracheostomy in two airway trauma patients suspected of COVID-19: A case report
Coronavirus disease 2019, known as COVID-19, was first identified in Wuhan, China, in December 2019 and became a pandemic on Mar 11, according to the World Health Organization report. In the epidemic of COVID-19, many patients admitted to hospitals for other reasons may be silent carriers of COVID-19 and have the risk of infecting medical personnel. Thus, meticulous personal protection measures should be considered in suspicious patients, especially when close contact with the patient�s airway is anticipated. We introduce two airway trauma patients suspected of COVID-19 who required emergency tracheostomy. Patient one was a 29-year-old man who suffered facial trauma following a car accident. A chest CT scan showed peripheral ground-glass opacities suggestive for COVID-19. The second patient was a young elevator mechanic who experienced maxillofacial trauma after an elevator crash. The methods of anesthesia and airway protection and safety precautions are described. © 2020, Author(s)
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