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• Time-dependent pathogen rate reduction in 3-D fracture network fractures. • 3-D E. coli transport simulation in networks of thousands of fractures. • Extended colloid filtration theory predicts pathogen BTC & 3-D plume in groundwater. • Model simulations were supported by field sampling and laboratory filtration tests. • Potential pathogen release to the bathing water is possible during floods. Microbial transport in fractured carbonate rock using enhanced solutions is a significant and neglected research topic in the literature. We propose an extended colloid filtration theory (CFT) combined with a particle-tracking following streamlines (PTFS) model for the rapid prediction of breakthrough curves (BTCs) and plumes of pathogens in three-dimensional (3-D) discrete fracture networks (DFNs). We adapted CFT in porous media to pathogen transport in fractures containing Terra Rossa (soil) deposits. As an example of the model capability, a simulation was used to predict the 3-D motion field and Escherichia coli count in groundwater originating from the Forcatella managed aquifer recharge (MAR) Facility (Brindisi, Italy) using a DFN composed of 3,900 fractures. In arid regions, MAR facilities are significant for sustaining basic human needs, such as freshwater supply for drinking and crop production. The Markov chain Monte Carlo (MCMC) technique was applied to E. coli counts in the collected water samples to increase data representativeness. The pathogen transport coefficients were further supported by batch filtration tests carried out in the CNR/IRSA Laboratory (Bari, Italy). The mean E. coli attachment rate coefficient of 0.15 × 10−8 m2 d–1 (sticking efficiency = 1.1 × 10−8 m) resulted in a 2.1 log 10 removal in 600 m of reclaimed water filtration. The simulation output visualized the E. coli 3-D pathways in groundwater and the positions of contaminated groundwater spring outflows on Forcatella Beach. The simulation results agreed with the mean MCMC output of E. coli concentrations in bathing water under unperturbed geochemical and environmental flow and transport conditions. However, results indicate that concentrations of pathogenic strains, parasites, and enteric viruses may enter the marine environment of MAR sites during flood periods. [Display omitted] [ABSTRACT FROM AUTHOR]

Although cell therapy has been applied in regenerative medicine for decades, recent years have seen greatly increased attention being given to the use of stem cell-based derivatives such as cell-free secretome. Dental pulp stem cells (DPSCs) are widely available, easily accessible, and have high neuroprotective and angiogenic properties. In addition, DPSC-derived secretome contains a rich mixture of trophic factors. The current investigation evaluated the short-term therapeutic effects of human DPSCs and their secretome in a rat model of mild ischemic stroke. Mild ischemic stroke was induced by 30 min middle cerebral artery occlusion, and hDPSCs or their secretome was administered intra-arterially and intranasally. Neurological function, infarct size, spatial working memory, and relative expression of seven target genes in two categories of neurotrophic and angiogenic factors were assessed three days after stroke. In the short-term, all treatments reduced the severity of neurological and histological deficits caused by ischemic stroke. Moreover, transient middle cerebral artery occlusion led to the striatal and cortical over-expression of BDNF, NT-3, and angiogenin, while NGF and VEGF expression was reduced. Almost all interventions were able to modulate the expression of target genes after stroke. The obtained data revealed that single intra-arterial administration of hDPSCs or their secretome, single intranasal transplantation of hDPSCs, or repeated intranasal administration of hDPSC-derived secretome was able to ameliorate the devastating effects of a mild stroke, at least in the short-term. [Display omitted] • Dental pulp stem cells (DPSCs) or their secretome were capable of improving stroke injury. • DPSCs or their secretome reduced neurological and histological deficits following ischemic stroke. • Transient MCAO led to striatal and cortical over-expression of BDNF, NT-3, and angiogenin, while NGF and VEGF expression was reduced. • DPSCs or their secretome modulated the expression of target genes after stroke. [ABSTRACT FROM AUTHOR]

Rapidly growing topic, the discrete fracture network engineering (DFNE), has already attracted many talents from diverse disciplines in academia and industry around the world to challenge difficult problems related to mining, geothermal, civil, oil and gas, water and many other projects. Although, there are few commercial software capable of providing some useful functionalities fundamental for DFNE, their costs, closed code (black box) distributions and hence limited programmability and tractability encouraged us to respond to this rising demand with a new solution. This paper introduces an open source comprehensive software package for stochastic modeling of fracture networks in two- and three-dimension in discrete formulation. Functionalities included are geometric modeling (e.g., complex polygonal fracture faces, and utilizing directional statistics), simulations, characterizations (e.g., intersection, clustering and connectivity analyses) and applications (e.g., fluid flow). The package is completely written in Matlab scripting language. Significant efforts have been made to bring maximum flexibility to the functions in order to solve problems in both two- and three-dimensions in an easy and united way that is suitable for beginners, advanced and experienced users. [ABSTRACT FROM AUTHOR]

1-Allyl-3-methylimidazolium tetraflouroborate ([AMIM][BF 4 ]) ionic liquid modified carbon-ceramic electrode was applied for Imidacloprid electrochemical determination. Surface of the modified electrode was characterized using s canning electron microscopy (SEM), and Energy Dispersive X-ray Analysis (EDX). These analyses showed the deposition of ionic liquid on the surface of carbon-ceramic electrode caused formation of graphene-like nanoplatelets. Based on high surface area and rich edge defects which resulting from graphene-like nanoplatelets and high ionic conductivity of ionic liquid (IL), the modified electrode exhibited electro-catalytic activity for Imidacloprid reduction. Operational parameters including IL volume, solution pH; which affect the analytical performance of modified electrode were optimized. The calibration curve for Imidaclopride was linear in the range of 5 × 10 −8 –7 × 10 −6 M with the detection limit (S/N = 3) of 31 nM (3.1 × 10 −8 M). This modified electrode was applied for imidacloprid determination in some commercial formulation and agricultural products and the results were in good agreement with standard high-performance liquid chromatography method. [ABSTRACT FROM AUTHOR]

Objectives: There are several reports of the association between SARS-CoV-2 infection (COVID-19) and cerebral venous sinus thrombosis (CVST). In this study, we aimed to compare the hospitalization rate of CVST before and during the COVID-19 pandemic (before vaccination program).Materials and Methods: In this retrospective cohort study, the hospitalization rate of adult CVST patients in Namazi hospital, a tertiary referral center in the south of Iran, was compared in two periods of time. We defined March 2018 to March 2019 as the pre-COVID-19 period and March 2020 to March 2021 as the COVID-19 period.Results: 50 and 77 adult CVST patients were hospitalized in the pre-COVID-19 and COVID-19 periods, respectively. The crude CVST hospitalization rate increased from 14.33 in the pre-COVID-19 period to 21.7 per million in the COVID-19 era (P = 0.021). However, after age and sex adjustment, the incremental trend in hospitalization rate was not significant (95% CrI: -2.2, 5.14). Patients > 50-year-old were more often hospitalized in the COVID-19 period (P = 0.042). SARS-CoV-2 PCR test was done in 49.3% out of all COVID-19 period patients, which were positive in 6.5%. Modified Rankin Scale (mRS) score ≥3 at three-month follow-up was associated with age (P = 0.015) and malignancy (P = 0.014) in pre-COVID period; and was associated with age (P = 0.025), altered mental status on admission time (P<0.001), malignancy (P = 0.041) and COVID-19 infection (P = 0.008) in COVID-19 period.Conclusion: Since there was a more dismal outcome in COVID-19 associated CVST, a high index of suspicion for CVST among COVID-19 positive is recommended. [ABSTRACT FROM AUTHOR]

• Detailed comparison of LDPM and FDEM for analyzing cracking in concrete. • Uniquely validated models by comparing versus the size effect law. • Study of influencial parameters on the size effect. • Statistical analysis of concrete performance. • Fracturing patterns in concrete weight coating of offshore pipelines. We study the structural response of concrete weight coating of offshore pipelines subject to various loading conditions by utilizing the Lattice Discrete Particle Model and Finite Discrete Element Method in a comparative manner. We use laboratory experiments to validate our numerical simulations. We discuss the framework in detail, experiment setups, and outline the capabilities and limitations of both methods. A parametric study with a correlation to the size effect is also presented. We simulate Uniaxial Compressive Strength, Brazilian Disk and a three-point bending of a beam with a notch in both methods. We observe that strength and macroscopic fracture patterns fit well between numerical and experimental methods. We discuss the effectiveness of the methods concerning the transition of size effect, as well as comparing to the size effect law. Our statistical analysis quantifies the capability of capturing the size effect in both models. Capturing the size effect helps to increase the accuracy of predicting the structure response and performance which in turn a key factor in durability of concrete structures. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study is to identify geochemical anomalies using power spectrum–area (S–A) method based on the grade values of Cu, Mo and Au in 2709 soil samples collected from Kahang porphyry-type Cu deposit, Central Iran. S–A log–log plots indicated that there are three stages of Cu, Mo and Au enrichment. The third enrichment was considered as the main stage for the presence of Cu, Mo and Au at the concentrations above 416ppm, 23ppm and 71ppb, respectively. Elemental anomalies are positively associated with monzo–granite–diorite and breccias units which are in the central and western parts of the deposit. The anomalies are located within the potassic, phyllic and argillic alteration types and also there is the positive correlation between the anomalies and nearing faults in the studied area. The results obtained via fractal model were interpreted accordingly to incorporate the information for the mineralized areas including detailed geological map, structural analysis and alterations. The results show that S–A multifractal modeling is applicable for anomalies delineation based on soil data. [Copyright &y& Elsevier]

• Developed local discretization methods to account for aggregate fracture. • Compared crack patterns between experimental and numerical results. • Introduced framework for inclusion of irregularly shaped entrapped air voids. • Evaluated impact of aggregate fracture on three-point bending models. We describe simple and practical innovative developments of the Lattice Discrete Particle Model (LDPM) that capture fracturing (failure) through aggregates in concrete. While the original LDPM treats aggregates as rigid bodies that do not fail, for realistic modeling of cracking observed in High Strength Concrete (HSC), the aggregate cracking must be included. We compared the results of our method with the scans of actual cracking and could obtain matching fracturing patterns. Moreover, good fits were found for HSC brittleness when comparing the simulation results with the experimental for models of a three-point bending beam with a notch. [ABSTRACT FROM AUTHOR]

Due to the importance of hydrogen as an effective antioxidant for its applications in therapy, this research reports the fabrication of a coupled microfluidic microbial electrochemical cell (MXC), including microfluidic microbial fuel cells (MFCs) and a microfluidic microbial electrolysis cell (MEC) series in order to perform it as a self-powered biohydrogen generator. Being able to be a platform of implantable medical devices, utilization a non-phatogenic strain of Escherichia coli as the biocatalyst in order to exploit the embodied energy from human blood and excrement and finally the use of cheap and facile materials (<$2 per device) are the exceptional features of the system. The sustainable potential difference for a series of three microfluidic MFCs is 1.97 V, and is high and sufficient for hydrolyzing an organic substrate. The single cell has a capability for producing the maximum power density of 20 W m−3 and the three cells series connection achieve as 38.2 W m−3 as the highest collective power. The maximum hydrogen production rate of 46 and 28 ppm h−1 obtain for glucose and urea-based substrates, respectively. The coupled microfluidic MXC performance characterize based on its substrate type, concentration, flow rate as well as comparison with other conventional MECs. Image 1 • A self-powered microfluidic biohydrogen generator was developed. • Non-phatogenic strain of Escherichia coli was used as biocatalyst of the system. • The spiral microchannel expedites the bacteria precipitation and biofilm formation. • The maximum hydrogen rate of 46 ppm h−1 was obtained for glucose-based substrate. [ABSTRACT FROM AUTHOR]

Inflammation can involve several ocular structures, including the sclera, retina, and uvea, and cause vascular changes in these tissues. Although retinal vasculitis is the most common finding associated with uveitis involving the posterior segment, other vascular abnormalities may be seen in the retina. These include capillary nonperfusion and ischemia, vascular occlusions, preretinal neovascularization, microaneurysms and macroaneurysms, and telangiectasia. Moreover, vasoproliferative tumors and subsequent coat-like response can develop secondary to uveitis. Fluorescein angiography is ideal for the investigation of retinal vascular leakage and neovascularization, while optical coherence tomography angiography can provide depth resolved images from the superficial and deep capillary plexus and can demonstrate vascular remodeling. Choroidal vascular abnormalities primarily develop in the choriocapillaris or in the choroidal stroma and can appear as flow void in optical coherence tomography angiography and filling defect and vascular leakage in indocyanine green angiography. Extensive choriocapillaris nonperfusion in the presence of choroidal inflammation can increase the risk of choroidal neovascular membrane development. Iris vascular changes may manifest as dilation of vessels in stroma due to inflammation or rubeosis that is usually from ischemia in retinal periphery secondary to chronic inflammation. More severe forms of scleral inflammation, such as necrotizing scleritis, are associated with vascular occlusion in the deep episcleral plexus, which can lead to necrosis of sclera layer and uveal exposure. • Inflammation can involve several ocular structures, including the sclera, retina, and uvea. • Retinal vasculitis is the most common finding associated with uveitis involving the posterior segment. • Other vascular abnormalities can be seen in the retina, all uveal tissues including iris and choroid and sclera. • Fluorescein angiography, optical coherence tomography angiograph, indocyanine green angiography are ancillary tests that are commonly used for the diagnosis of vascular changes and abnormalities in ocular structures. [ABSTRACT FROM AUTHOR]

Abstract: Buckling and postbuckling behavior of metal plates is governed by their slenderness parameter. Using nonlinear finite element simulations, unstiffened mild carbon steel, stainless steel and aluminum plates under the action of axial compression are first classified into slender, moderate and stocky plates. Then the effects of initial imperfection amplitude on each plate type and material is studied via sensitivity analyses. The results show that the transition from slender to stocky plates, regardless of material type, occurs at the slenderness parameter of 2. Empirical equations for evaluating the buckling and postbuckling capacities of imperfect plates are drawn out. It is observed that the increase of imperfection amplitude decreases the buckling load of slender plates, but their postbuckling reserves and ultimate capacities are unaffected. In contrast, the ultimate strength of stocky plates is highly affected by initial imperfections. [Copyright &y& Elsevier]

Abstract: The anticonvulsant effects of agmatine, an endogenous polyamine and a metabolite of l-arginine, have been shown in various experimental seizure models. Agmatine also potentiates the anti-seizure activity of morphine. The present study aimed to investigate a possible involvement of nitric oxide (NO) pathway in the protection by agmatine and morphine co-administration against pentylenetetrazole (PTZ) –induced seizure in male mice. To this end, the thresholds for the clonic seizures induced by the intravenous administration of PTZ, a GABA antagonist, were assessed. Intraperitoneal administration of morphine at lower dose (1mg/kg) increased the seizure threshold. Also intraperitoneal administration of agmatine (5 and 10mg/kg) increased the seizure threshold significantly. Combination of subeffective doses of morphine and agmatine led to potent anticonvulsant effects. Non-effective doses of morphine (0.1 and 0.5mg/kg) were able to induce anticonvulsant effects in mice pretreated with agmatine (3mg/kg). Concomitant administration of either the non-selective nitric oxide synthase (NOS) inhibitor L-NAME (1, 5mg/kg, i.p.) or the selective NOS inhibitor 7-NI (15, 30mg/kg, i.p.), with an ineffective combination of morphine (0.1mg/kg) plus agmatine (1mg/kg) produced significant anticonvulsant impacts. Moreover, the NO precursor, l-arginine (30, 60mg/kg, i.p.), inhibited the anticonvulsant action of agmatine (3mg/kg) plus morphine (0.5mg/kg) co-administration. Our results indicate that pretreatment of animals with agmatine enhances the anticonvulsant effects of morphine via a mechanism which may involve the NO pathway. [Copyright &y& Elsevier]