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1.
J Breast Imaging ; 6(3): 271-276, 2024 May 27.
Article in English | MEDLINE | ID: mdl-38625712

ABSTRACT

OBJECTIVE: The objectives of this Society of Breast Imaging (SBI)-member survey study were to assess the current imaging patterns for evaluation of symptomatic and asymptomatic breast implant integrity, including modalities used and imaging intervals. METHODS: A 12-question survey assessing the frequency of imaging modalities used to evaluate implant integrity, approximate number of breast implant integrity studies requested per month, intervals of integrity studies, and referring provider and radiology practice characteristics was distributed to members of the SBI. RESULTS: The survey response rate was 7.6% (143/1890). Of responding radiologists, 54.2% (77/142) were in private, 29.6% (42/142) in academic, and 16.2% (23/142) in hybrid practice. Among respondents, the most common initial examination for evaluating implant integrity was MRI without contrast at 53.1% (76/143), followed by handheld US at 46.9% (67/143). Of respondents using US, 67.4% (91/135) also evaluated the breast tissue for abnormalities. Among respondents, 34.1% (46/135) reported being very confident or confident in US for diagnosing implant rupture. There was a range of reported intervals for performing implant integrity studies: 39.1% (43/110) every 2-3 years, 26.4% (29/110) every 4-5 years, 15.5% (17/110) every 6-10 years, and 19.1% (21/110) every 10 years. CONCLUSION: For assessment of implant integrity, the majority of respondents (53.2%, 76/143) reported MRI as initial imaging test. US is less costly, but the minority of respondents (34.1%, 46/135) had confidence in US performance. Also, the minority of respondents (39.1%, 43/110) performed implant integrity evaluations every 2-3 years per the FDA recommendations for asymptomatic surveillance.


Subject(s)
Breast Implants , Magnetic Resonance Imaging , Practice Patterns, Physicians' , Humans , Female , Magnetic Resonance Imaging/statistics & numerical data , Practice Patterns, Physicians'/statistics & numerical data , Surveys and Questionnaires , Radiologists/statistics & numerical data , Societies, Medical , Ultrasonography, Mammary/statistics & numerical data , Prosthesis Failure
2.
Sci Total Environ ; 926: 171747, 2024 May 20.
Article in English | MEDLINE | ID: mdl-38531460

ABSTRACT

Conventional monitoring and mapping approaches are laborious, expensive, and time-consuming because they need a large number of data and consequently extensive sampling and experimental operations. Therefore, due to the growing concern about the potential of contamination of soils and agricultural products with heavy metals (HMs), a field experiment was conducted on 77 farm lands in an area of 2300 ha in the southeast of Shiraz (Iran) to investigate the source of metal contamination in the soils and vegetables and to model spatial distribution of HMs (iron, Fe; manganese, Mn; copper, Cu; zinc, Zn; cadmium, Cd; nickel, Ni, and lead, Pb) over the region using geographic information system (GIS) and geostatistical (Ordinary Kriging, OK) approaches and compare the results with deterministic approaches (Inverse Distance Weighting, IDW with different weighting power). Furthermore, some ecological and health risks indices including Pollution index (PI), Nemerow integrated pollution index (NIPI), pollution load index (PLI), degree of contamination (Cdeg), modified contamination degree (mCd), PIaverage and PIvector for soil quality, multi-element contamination (MEC), the probability of toxicity (MERMQ), the potential ecological index (RI), total hazard index (THI) and total carcinogenic risk index (TCR) based on ingestion, inhalation, and dermal exposure pathways for adults and children respectively for analyzing the noncarcinogenic and carcinogenic risks were calculated. Experimental semivariogram of the mentioned HMs were calculated and theoretical models (i.e., exponential, spherical, Gaussian, and linear models) were fitted in order to model their spatial structures and to investigate the most representative models. Moreover, principal component analysis (PCA) and cluster analysis (CA) were used to identify sources of HMs in the soils. Results showed that IDW method was more efficient than the OK approach to estimate the properties and HMs contents in the soils and plants. The estimated daily intake of metals (DIM) values of Pb and Ni exceeded their safe limits. In addition, Cd was the main element responsible for ecological risk. The PIave and PIvector indices showed that soil quality in the study area is not suitable. According to mCd values, the soils classified as ultra-high contaminated for Cu and Cd, extremely high for Zn and Pb, very high, high, and very low degree of contamination for Ni, Mn, and Fe, respectively. 36, 60, and 4 % of the sampling sites had high, medium, and low risk levels with 49, 21, and 9 % probability of toxicity, respectively. The maximum health risk index (HRI) value of 20.42 with extremely high risk for children was obtained for Ni and the HI for adults and children were 0.22 and 1.55, respectively. The THI values of Pb and Cd were the highest compared to the other HMs studied, revealing a possible non-cancer risk in children associated with exposure to these metals. The routes of exposure with the greatest influence on the THI and TCR indices were in the order of ingestion > inhalation > dermal. Therefore, ingestion, as the main route of exposure, is the route of greatest contribution to health risks. PCA analysis revealed that Fe, Mn, Cu, and Ni may originate from natural sources, while Fe was appeared to be controlled by fertilizer, and Cu primarily coming from pesticide, while Cd and Pb were mainly associated with the anthropogenic contamination, atmospheric depositions, and terrific in the urban soils. While, Zn mainly originated from fertilization. Findings are vital for developing remediation approaches for controlling the contaminants distribution as well as for monitoring and mapping the quality and health of soil resources.


Subject(s)
Metals, Heavy , Soil Pollutants , Adult , Child , Humans , Vegetables , Geographic Information Systems , Environmental Monitoring , Cadmium/analysis , Copper/analysis , Lead/analysis , Risk Assessment , Metals, Heavy/analysis , Soil/chemistry , Carcinogens/analysis , Receptors, Antigen, T-Cell , Soil Pollutants/analysis , China
3.
PLoS One ; 19(1): e0296933, 2024.
Article in English | MEDLINE | ID: mdl-38198486

ABSTRACT

Hydraulic conductivity (Kψ) is one of the most important soil properties that influences water and chemical movement within the soil and is a vital factor in various management practices, like drainage, irrigation, erosion control, and flood protection. Therefore, it is an essential component in soil monitoring and managerial practices. The importance of Kψ in soil-water relationship, difficulties for its measurement in the field, and its high variability led us to evaluate the potential of stepwise multiple linear regression (SMLR), and multilayer perceptron (MLPNNs) and radial-basis function (RBFNNs) neural networks approaches to predict Kψ at tensions of 15, 10, 5, and 0 cm (K15, K10, K5, and K0, respectively) using easily measurable attributes in calcareous soils. A total of 102 intact (by stainless steel rings) and composite (using spade from 0-20 cm depth) soil samples were collected from different land uses of Fars Province, Iran. The common physico-chemical attributes were determined by the common standard laboratory approaches. Additionally, the mentioned hydraulic attributes were measured using a tension-disc infiltrometer (with a 10 cm radius) in situ. Results revealed that the most of studied soil structure-related parameters (soil organic matter, soluble sodium, sodium adsorption ratio, mean weight diameter of aggregates, pH, and bulk density) are more correlated with K5 and K0 than particle-size distribution-related parameters (sand, silt, and standard deviation and geometric mean diameter of particles size). For K15 and K10, the opposite results were obtained. The applied approaches predicted K15, K10, K5, and K0 with determination coefficient of validation data (R2val) of 0.52 to 0.63 for SMLR; 0.71 to 0.82 for MLPNNs; and 0.58 to 0.78 for RBFNNs. In general, the capability of the applied methods for predicting Kψ at all the applied tensions was ranked as MLPNNs > RBFNNs > SMLR. Although the SMLR method provided easy to use pedotransfer functions for predicting Kψ in calcareous soils, the present study suggests using the MLPNNs approach due to its high capability for generating accurate predictions.


Subject(s)
Neural Networks, Computer , Soil , Linear Models , Sodium , Water
4.
Environ Sci Pollut Res Int ; 31(2): 3222-3238, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38085482

ABSTRACT

Although assisted phytoremediation using chemical treatments is a suitable technique for the removal of heavy metals (HMs), the estimation of this process using simple models is also crucial. For this purpose, a greenhouse trial was designed to evaluate the effectiveness of citric, oxalic, and tartaric acid on Cd, Pb, Ni, and Zn phytoremediation by maize and sorghum and to estimate this process using sigmoid HMs uptake model. Results showed that mean values of root and shoot dry weight and metals uptake, translocation factor (TF) of Pb and Zn, and uptake efficiency (UE) of Cd in maize were higher than sorghum but the TF of Cd and the phytoextraction efficiency (PEE) and UE of Pb in sorghum were higher than maize. Citric, oxalic, and tartaric acid significantly increased the UE of Pb by 17.7%, 22.5%, and 32.5%, respectively. Tartaric acid significantly increased the mean values of shoot dry weight, shoot Cd, Pb, and Ni uptake, and PEE of Pb and Ni, but decreased TF of Zn. The R2, NRMSE, and KM values indicated the ability of sigmoid HM uptake model in estimating HMs uptake in maize and sorghum treated with organic acids. Thus, tartaric acid was more effective than citric and oxalic acids to enhance phytoremediation potential. Sigmoid HM uptake model is suitable to estimate the HMs uptake in plants treated with organic acids at different growth stages.


Subject(s)
Metals, Heavy , Soil Pollutants , Sorghum , Tartrates , Zea mays , Cadmium/analysis , Lead , Soil Pollutants/analysis , Metals, Heavy/analysis , Biodegradation, Environmental , Citric Acid , Soil
5.
J Neurosurg Spine ; 40(3): 389-394, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38064706

ABSTRACT

OBJECTIVE: The goal in this study was to explore the spatial relationship of perimedullary vessels visualized on MRI to localize the side and the site of spinal dural arteriovenous fistula (SDAVF). METHODS: A retrospective analysis of 30 consecutive patients diagnosed with SDAVF on MRI was undertaken. Two experienced reviewers blinded to all reports and angiographic images analyzed T2-weighted as well as postcontrast T1-weighted sequences. A focal prominent zone of perimedullary vessels with lateralization to one side in the thecal space was evaluated to locate the side and the site of the fistula. Spinal digital subtraction angiography served as the gold standard technique. RESULTS: Good interrater agreement (κ = 0.77) was shown for the diagnosis of SDAVF with perimedullary vessels on T2-weighted MRI. Flow voids on T2-weighted MRI demonstrated a sensitivity of 1.0 (95% CI 1.0-1.0) and an accuracy of 0.87 (95% CI 0.79-0.95) to identify the presence of fistula. The flow voids on T2-weighted MRI also demonstrated 0.88 (95% CI 0.71-1.03) sensitivity and 0.81 (95% CI 0.70-0.92) accuracy to identify the side of SDAVF. Furthermore, flow voids on T2-weighted MRI showed 0.87 (95% CI 0.71-1.03) sensitivity and 0.87 (95% CI 0.79-0.95) accuracy to identify the site of SDAVF within 3 vertebral levels above or below the actual site. Area under the receiver operating characteristic curve demonstrated significant results (0.87 [95% CI 0.73-1.0]; p < 0.001) for flow voids on T2-weighted MRI to identify the site of shunts within 3 vertebral levels in the cranial or caudal direction. CONCLUSIONS: Spatial distribution of perimedullary vessels observed on standard MRI show promise to locate the side and the site of fistula in patients with SDAVF.


Subject(s)
Central Nervous System Vascular Malformations , Fistula , Humans , Retrospective Studies , Central Nervous System Vascular Malformations/diagnostic imaging , Angiography, Digital Subtraction , Magnetic Resonance Imaging
6.
Environ Monit Assess ; 196(1): 96, 2023 Dec 28.
Article in English | MEDLINE | ID: mdl-38153593

ABSTRACT

Mitigation of global climate change by means such as soil carbon (C) sequestration has become an important area of research. Soil organic matter (SOM) that is stabilized with clay minerals is the most persistent in soils. Currently, little is known regarding the C sequestration ability of nanoclay extracted from Vertisols in semi-arid regions. Therefore, the aim of this study was to extract and characterize nanoclay and bulk clay from a Vertisol from Iran, in terms of physicochemical surface properties and resistance of SOM to chemical oxidation. The clay fractions were studied before and after H2O2 treatment by total C analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), dynamic light scattering (DLS), pyrolysis gas chromatography mass spectrometry (GC-MS), Fourier transform infrared (FTIR) spectroscopy, specific surface area analysis, and zeta potential. TEM and SEM images showed that the diameter of the extracted nanoclays was 16-46 nm and their morphology was more porous than bulk soil clay. The nanoclay had a much greater specific surface area (111.9 m2 g-1) than the bulk clay (67.9 m2 g-1). According to total C, FTIR, and zeta potential results, the nanoclay was enriched with 1.4 times more C than the bulk clay after peroxide treatment, indicating enhanced soil C stabilization in the nanoclay. About 45% of the peroxide-resistant SOM in the nanoclay was associated with N-containing compounds, indicating that these compounds contribute to SOM stability. The results demonstrate important role of nanoclay in soil C sequestration in Vertisols.


Subject(s)
Carbon Sequestration , Hydrogen Peroxide , Clay , Environmental Monitoring , Soil , Peroxides
7.
Sci Rep ; 13(1): 18861, 2023 Nov 01.
Article in English | MEDLINE | ID: mdl-37914697

ABSTRACT

Due to the high performance of hydrophobic surfaces in pressure drop reduction, they have been proposed for various applications. However, despite the extensive uses of two-phase flows in many industries, the effect of hydrophobic surfaces on the pressure drop reduction of two-phase flows has not been well understood yet. Thus, in the present study, by implementing the phase-field and finite element methods, the bubbly flows as an example of two-phase flows are considered for examining the effect of hydrophobic microgrooved microchannels on the pressure drop reduction of these regimes in the laminar state. We found out that hydrophobic microgrooved surfaces not only can be efficient in the bubbly flow but also can even cause a maximum pressure drop reduction of up to 70%, which is almost 3.5 times higher than in single-phase flow. We also studied the influence of each parameter, such as bubbles volume or length, Reynolds number, capillary number, and their combination on this phenomenon. The pressure drop reduction grows by increasing the volume of the bubbles but decreases by increasing the flow velocity or the surface tension coefficient. The combination of these parameters demonstrated different results in some circumstances.

8.
Environ Monit Assess ; 195(11): 1367, 2023 Oct 24.
Article in English | MEDLINE | ID: mdl-37875717

ABSTRACT

The soil's physical and mechanical (SPM) properties have significant impacts on soil processes, such as water flow, nutrient movement, aeration, microbial activity, erosion, and root growth. To digitally map some SPM properties at four global standard depths, three machine learning algorithms (MLA), namely, random forest, Cubist, and k-nearest neighbor, were employed. A total of 200-point observation was designed with the aim of a field survey across the Marvdasht Plain in Fars Province, Iran. After sampling from topsoil (0 to 30 cm) and subsoil depths (30 to 60 cm), the samples were transferred to the laboratory to determine the mean weight diameter (MWD) and geometric mean diameter (GMD) of aggregates in the laboratory. In addition, shear strength (SS) and penetration resistance (PR) were measured directly during the field survey. In parallel, 79 environmental factors were prepared from topographic and remote sensing data. Four soil variables were also included in the modeling process, as they were co-located with SPM properties based on expert opinion. For selecting the most influential covariates, the variance inflation factor (VIF) and Boruta methods were employed. Two covariate dataset scenarios were used to assess the impact of soil and environmental factors on the modeling of SPM properties including SPM and environmental covariates (scenario 1) and SPM, environmental covariates, and soil variables (scenario 2). From all covariates, nine soil and environmental factors were selected for modeling the SPM properties, of which four of them were the soil variables, three were related to remote sensing, and two factors had topographic sources. The results indicated that scenario 2 outperformed in all standard depths. The findings suggested that clay and SOM are key factors in predicting SPM, highlighting the importance of considering soil variables in addition to environmental covariates for enhancing the accuracy of machine learning prediction. The k-nearest neighbor algorithm was found to be highly effective in predicting SPM, while the random forest algorithm yielded the highest R2 value (0.92) for penetration resistance properties at 15-30 depth. Overall, the approach used in this research has the potential to be extended beyond the Marvdasht Plain of Fars Province, Iran, as well as to other regions worldwide with comparable soil-forming factors. Moreover, this study provides a valuable framework for the digital mapping of SPM properties, serving as a guide for future studies seeking to predict SPM properties. Globally, the output of this research has important significance for soil management and conservation efforts and can facilitate the development of sustainable agricultural practices.


Subject(s)
Environmental Monitoring , Soil , Iran , Environmental Monitoring/methods , Clay , Agriculture
9.
Langmuir ; 39(31): 10978-10992, 2023 Aug 08.
Article in English | MEDLINE | ID: mdl-37489709

ABSTRACT

Drag force, corrosion, and biofouling have always been issues that disrupt the reliable operation of systems dealing with fluid flow. Inspired by nature, liquid- or solid-infused surfaces are brand-new surfaces that can address these problems. The present study examines nine comprehensive yet affordable samples with different surface structures, from the nanoscale to the microscale on the aluminum substrate. These surface structures, modified with stearic acid or octadecyltrichlorosilane, are infiltrated with various lubricants. The wetting test shows the magnificent slippery properties of fabricated surfaces with a contact angle hysteresis lower than 10°. The conducted polarization test reveals that the surface structures comprised of aluminum oxide or boehmite have good anti-corrosion properties. Moreover, the higher the viscosity of the lubricant, the better the anti-corrosion abilities. In the anti-bacterial tests, the surfaces possessing a liquid lubricant perform better than those containing solid ones; among them, those with lower viscosities are preferable. The frictional drag test carried out in an aquarium shows that for viscous working fluids, the layered-double hydroxide (LHD) surface containing silicone oil with a viscosity of 5 mPa s could provide a maximum drag reduction of 18%. By increasing the velocity of the surface, the drag reduction ability of LIS reduces. For more viscous lubricants and also solid ones, no appreciable drag reduction is achieved. For less viscous working fluid, however, the anodized surface filled with the same lubricant shows the best results with a maximum drag reduction of 15%. The surface based on LDH also shows good durability in the conducted stability tests.

10.
Langmuir ; 39(23): 8354-8366, 2023 Jun 13.
Article in English | MEDLINE | ID: mdl-37267064

ABSTRACT

Improving the shedding rate of condensed droplets has many applications in industries and daily problems, including increasing heat transfer and self-cleaning properties. One way to achieve this goal is by enhancement of the wetting properties of surfaces. In this research, the hierarchical superhydrophobic coating over aluminum has been applied using a relatively cost-effective method, spraying, which is also applicable to any metal surface used as a condenser. According to the results obtained from the experimental tests, the fabricated surface is highly superhydrophobic, with a contact angle of 158° and contact angle hysteresis of less than 5°. The results show that the presented surface increases the heat transfer coefficient by 20.6% at the subcooling temperature of 25.5 °C when the surface temperature and relative humidity are 70 °C and 98%, respectively. In addition, this coated surface showed great potential at lower surface temperatures by increasing the water condensation rate as much as 50.5% at the subcooling temperature of 12 °C, when the surface temperature and relative humidity are 11.25 °C and 70%, respectively. Therefore, it is found that for the fabricated superhydrophobic paint in the present study, the effectiveness of the dropwise condensation mode profoundly depends on surface temperatures besides subcooling temperatures. In other words, a surface with lower temperatures shows better performance for the same subcooling temperatures. In addition, various types of durability tests are carried out. The results reveal that this coating has good durability against high surface temperatures, submerged conditions for 30 days, imposing hot steam for 150 h, corrosion, and organic solvents. Hence, it is suitable for industrial applications.

11.
J Chem Phys ; 158(7): 074702, 2023 Feb 21.
Article in English | MEDLINE | ID: mdl-36813725

ABSTRACT

We numerically investigate the pressure drop reduction (PDR) performance of microchannels equipped with liquid-infused surfaces, along with determining the shape of the interface between the working fluid and lubricant within the microgrooves. The effects of different parameters, such as the Reynolds number of working fluid, density and viscosity ratios between the lubricant and working fluid, the ratio of the thickness of the lubricant layer over the ridges to the depth of the groove, and the Ohnesorge number as a representative of the interfacial tension, on the PDR and interfacial meniscus within the microgrooves are comprehensively studied. The results reveal that the density ratio and Ohnesorge number do not significantly affect the PDR. On the other hand, the viscosity ratio considerably affects the PDR, and a maximum PDR of 62% compared to a smooth non-lubricated microchannel is achieved for a viscosity ratio of 0.01. Interestingly, the higher the Reynolds number of the working fluid, the higher the PDR. The meniscus shape within the microgrooves is strongly affected by the Reynolds number of the working fluid. Despite the insignificant effect of interfacial tension on the PDR, the interface shape within the microgrooves is appreciably influenced by this parameter.

12.
Clin Perinatol ; 49(3): 603-621, 2022 09.
Article in English | MEDLINE | ID: mdl-36113925

ABSTRACT

Advances in pre and postnatal neuroimaging techniques, and molecular genetics have increased our understanding of the congenital malformation of the brain. Correct diagnosis of these malformations in regards to embryology, and molecular neurogenetics is of paramount importance to understand the inheritance pattern and risk of recurrence. Lesions detected on prenatal imaging require confirmation either with postnatal ultrasound and/or with MR imaging. With the advent of the faster (rapid) MRI techniques, which can be conducted without sedation, MRI is commonly used in the evaluation of congenital malformation of the brain. Based on neuroimaging pattern, the congenital malformations of the posterior fossa are classified into 4 main categories: (a) predominantly cerebellar, (b) cerebellar and brainstem, (c) predominantly brainstem, and (d) predominantly midbrain malformations.


Subject(s)
Cerebellum , Neuroimaging , Brain , Cerebellum/abnormalities , Cerebellum/diagnostic imaging , Female , Humans , Magnetic Resonance Imaging/methods , Mesencephalon/abnormalities , Neuroimaging/methods , Pregnancy
13.
Biomed Res Int ; 2021: 9926128, 2021.
Article in English | MEDLINE | ID: mdl-34327241

ABSTRACT

Interest in the design and manufacture of RNA and DNA aptamers as apta-biosensors for the early diagnosis of blood infections and other inflammatory conditions has increased considerably in recent years. The practical utility of these aptamers depends on the detailed knowledge about the putative interactions with their target proteins. Therefore, understanding the aptamer-protein interactions at the atomic scale can offer significant insights into the optimal apta-biosensor design. In this study, we consider one RNA and one DNA aptamer that were previously used as apta-biosensors for detecting the infection biomarker protein TNF-α, as an example of a novel computational workflow for selecting the aptamer candidate with the highest binding strength to a target. We combine information from the binding free energy calculations, molecular docking, and molecular dynamics simulations to investigate the interactions of both aptamers with TNF-α. The results reveal that the RNA aptamer has a more stable structure relative to the DNA aptamer. Interaction of aptamers with TNF-α does not have any negative effect on its structure. The results of molecular docking and molecular dynamics simulations suggest that the RNA aptamer has a stronger interaction with the protein. Also, these findings illustrate that basic residues of TNF-α establish more atomic contacts with the aptamers compared to acidic or pH-neutral ones. Furthermore, binding energy calculations show that the interaction of the RNA aptamer with TNF-α is thermodynamically more favorable. In total, the findings of this study indicate that the RNA aptamer is a more suitable candidate for using as an apta-biosensor of TNF-α and, therefore, of greater potential use for the diagnosis of blood infections. Also, this study provides more information about aptamer-protein interactions and increases our understanding of this phenomenon.


Subject(s)
Aptamers, Nucleotide/metabolism , DNA/metabolism , RNA/metabolism , Tumor Necrosis Factor-alpha/metabolism , Molecular Docking Simulation , Molecular Dynamics Simulation , Thermodynamics
14.
Nanotechnology ; 32(19): 195302, 2021 May 07.
Article in English | MEDLINE | ID: mdl-33503594

ABSTRACT

Superhydrophobic surfaces demonstrate significant characteristics which make them suitable for a wide variety of applications. In this study, we propose a facile, one-step, and cost-effective anodizing scheme using aluminum nitrate/stearic acid mixture solution to create a superhydrophobic surface on an aluminum mesh. The surface outperforms the surface anodized by the widely used oxalic acid solution in terms of superhydrophobicity and water-surface friction behavior. The proposed surface reduced the friction by 11% on average respective to the surface prepared by oxalic acid. The durability of the introduced superhydrophobic surface has also been investigated. The proposed surface retained its high water contact angle and showed higher hydrophobicity relative to the surface anodized by oxalic acid after ten abrasion cycles. This method and surface may be used for numerous applications due to its ease of fabrication, low cost, and excellent performance in energy-loss reduction.

15.
Nanotechnology ; 32(4): 045706, 2021 Jan 22.
Article in English | MEDLINE | ID: mdl-32906105

ABSTRACT

In this study, via molecular dynamic simulations, we showed that the latest described graphene-like carbon nitride membranes, such as g-C4N3, g-C6N6, and g-C3N4 single-layers, can be used as high-performance membranes for water desalination. In addition to having inherent nanopores and extraordinary mechanical properties, the carbon nitride membranes have high water permeability and strong ion rejection (IR) capability. The important point about carbon nitride membranes is that the open or closed state of the pores can be changed by applying tensile stress and creating a positive strain on the membrane. The effect of the imposed pressure, the tensile strain, the ion concentration, and the effective pore size of the membranes are reported. It is demonstrated that, with the applied tensile strain of 12%, the g-C6N6 membrane is the best purification membrane, with a water permeability of 54.16 l cm-2 d-1 MPa-1 and the IR of 100%. Its water permeability is one order of magnitude greater than other one-atom-thick membranes.

16.
Sci Rep ; 10(1): 9293, 2020 06 09.
Article in English | MEDLINE | ID: mdl-32518389

ABSTRACT

Droplet-based microfluidic logic gates have many applications in diagnostic assays and biosciences due to their automation and the ability to be cascaded. In spite of many bio-fluids, such as blood exhibit non-Newtonian characteristics, all the previous studies have been concerned with the Newtonian fluids. Moreover, none of the previous studies has investigated the operating regions of the logic gates. In this research, we consider a typical AND/OR logic gate with a power-law fluid. We study the effects of important parameters such as the power-law index, the droplet length, the capillary number, and the geometrical parameters of the microfluidic system on the operating regions of the system. The results indicate that AND/OR states mechanism function in opposite directions. By increasing the droplet length, the capillary number and the power-law index, the operating region of AND state increases while the operating region of OR state reduces. Increasing the channel width will decrease the operating region of AND state while it increases the operating region of OR state. For proper operation of the logic gate, it should work in both AND/OR states appropriately. By combining the operating regions of these two states, the overall operating region of the logic gate is achieved.

17.
Am Surg ; 85(8): 865-870, 2019 Aug 01.
Article in English | MEDLINE | ID: mdl-31560305

ABSTRACT

In recent years, nonoperative management of complicated appendicitis has become more common. Patients managed nonoperatively do well, but there is a paucity of literature on patients who fail nonoperative management. The purpose of this study was to examine the overall failure rate, morbidity associated with failure, and potential predictors of failure in nonop management of appendicitis. This is a descriptive retrospective review of patients from a single hospital system who were diagnosed with advanced appendicitis and underwent nonop management between January 1, 2007, and November of 2017. The data were obtained through review of patient charts from the electronic medical record. Failure was defined as requirement of an operation due to ongoing infection secondary to appendicitis. There were 183 patients initially managed nonoperatively, with 70 patients failing nonoperative management. Patients failing nonoperative management experienced longer hospitalization (6.2 vs 2.9 days, P < 0.0001), and more patients in the failure group required admission to the ICU (10.0% vs 1.8%, P = 0.028). Multivariate analysis revealed that longer duration of symptoms reduced the likelihood of failure (odds ratio: 0.77 [0.64-0.92]). In this retrospective review, 38 per cent of patients failed nonop management of appendicitis. Symptom duration could provide insight for clinicians in assessing the role of nonoperative management because increasing symptom duration reduced the likelihood of failure.


Subject(s)
Appendicitis/therapy , Conservative Treatment , Case-Control Studies , Female , Humans , Intensive Care Units/statistics & numerical data , Length of Stay/statistics & numerical data , Male , Middle Aged , Retrospective Studies , Risk Factors , Treatment Failure
18.
Int J Phytoremediation ; 21(5): 435-447, 2019.
Article in English | MEDLINE | ID: mdl-30648415

ABSTRACT

Despite the fact that cadmium (Cd) is a non-essential element for plants, it can influence nutrients and affect human health. Potassium (K) can influence the transportation of heavy metals (HMs) in soil-plant systems. Here, a greenhouse experiment was conducted to evaluate the effect of Cd and K fertilizers on the different partitioning forms of HMs, their concentrations, uptake in the shoots and roots of Ocimum basilicum. Treatments comprised 2 levels of Cd (0 and 40 mg kg-1) and three levels of K (0, 100, and 200 mg kg-1) from three sources, i.e. KCl, K2SO4, and K-nano-chelate. 40 mg Cd kg-1 increased the shoot (above ground parts) Cd concentration. Addition of K as KCl, K2SO4, and K-nano-chelate increased the presence of Cd in shoots by 86, 82 and 76%, respectively, compared to the control. Using the nano-chelate of K can increase the accumulation of Cd in plants grown on contaminated soils to lesser content than that of the other forms of K. Application of 40 mg Cd kg-1 reduced the concentration of Zn, Cu, and Mn in the shoot, but increased shoot Fe concentration. Transfer factor (TF), which is the ratio of metal concentration in shoot to its concentration in root, of the studied HMs, was significantly affected by Cd and K treatments. Therefore, the proper form and dose of chemical fertilizers should be applied in Cd-contaminated soils.


Subject(s)
Metals, Heavy , Ocimum basilicum , Soil Pollutants/analysis , Biodegradation, Environmental , Cadmium/chemistry , Potassium , Soil/chemistry
19.
Am J Surg ; 217(3): 485-489, 2019 03.
Article in English | MEDLINE | ID: mdl-30415929

ABSTRACT

BACKGROUND: Current guidelines do not specifically address optimal antibiotic duration following cholecystostomy. This study compares outcomes for short-course (<7 days) and long-course (≥7 days) antibiotics post-cholecystostomy. METHODS: This was a retrospective review of cholecystostomy patients (≥18 years) admitted (1/1/2007-12/31/2017) to one healthcare system. RESULTS: Overall, 214 patients were studied. Demographics were similar, except short-course patients had higher Charlson Comorbidity Index (p < 0.0001). There were no intergroup differences in tachycardia (22.5%[short-course] vs 23.3%[long-course]) or leukocytosis (67.1%[short-course] vs 64.4%[long-course]) at drain placement nor time to normalization for pulse, temperature or leukocytosis. There were no differences regarding Clostridium Difficile infection (5.0%[short-course] vs 1.6%[long-course]) or cholecystitis recurrence (8.8%[short-course] vs 10.9%[long-course]). No differences were observed regarding gallbladder-related unplanned readmissions (30-day:18.8%[short-course] vs 17.2%[long-course]; 90-day: 20.0%[short-course] vs 25.8%[long-course]). There were no 30- or 90-day mortality differences (overall mortality: 18.3%). CONCLUSION: Post-cholecystostomy outcomes were comparable between short-course and long-course antibiotics, consistent with emerging literature supporting short-course antibiotics for intra-abdominal infection with source control.


Subject(s)
Anti-Bacterial Agents/administration & dosage , Cholecystitis/surgery , Cholecystostomy , Postoperative Complications/prevention & control , Adult , Aged , Female , Humans , Male , Retrospective Studies
20.
Adv Biomed Res ; 7: 82, 2018.
Article in English | MEDLINE | ID: mdl-29930922

ABSTRACT

BACKGROUND: Recent studies have shown that similar host glycan antigens are expressed by helminths such as Echinococcus granulosus hydatid cysts to evade from host immune system. In this work to investigate these antigens further, immunological cross-reactivity between human sera and hydatid cyst wall antigens has been investigated. MATERIALS AND METHODS: Hydatid cyst wall antigens were used in enzyme-linked immunosorbent assay and Western immunoblotting and probed with pooled sera of hydatidosis patients and healthy controls. Sodium metaperiodate treatment was used to investigate glycan antigens. RESULTS: A band with molecular weight about 53 KDa reacted with both hydatid patients' sera and also normal human sera. It has been shown that this band was a glycan antigen. CONCLUSIONS: A 53 KDa glycan antigen of hydatid cyst wall that reacted with all human sera may have an important role for evasion from host immune system.

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