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Steel‐concrete composite beams are commonly used in bridge construction. The corrosion of the supporting steel beams and the shear connectors are however known as a major cause of premature deterioration of composite bridges. Stainless steel beams and shear connectors offer a viable alternative solution to the steel corrosion problem in composite bridges located in harsh environmental conditions. This paper presents experimental and numerical investigations of the tensile and shear behaviour of stainless steel welded shear connectors. The results of tensile coupon and double shear tests on stainless steel and carbon steel shear connectors to characterise the tensile and shear response are reported. Numerical modelling is carried out using the ABAQUS finite element software to develop calibrated ductile damage and shear damage fracture models for stainless steel shear connectors. The development and validation of the numerical models together with the calibration of the fracture models are presented and comparisons are made with those of carbon steel shear connectors. [ABSTRACT FROM AUTHOR]

This study aimed to demonstrate the potential benefits of donepezil (DPZ) and vitamin D (Vit D) in combination to counteract the neurodegenerative disorders induced by CuSO4 intake in experimental rats. Neurodegeneration (Alzheimer-like) was induced in twenty-four male Wistar albino rats by CuSO4 supplement to drinking water (10 mg/L) for 14 weeks. AD rats were divided into four groups: untreated AD group (Cu-AD) and three treated AD groups; orally treated for 4 weeks with either DPZ (10 mg/kg/day), Vit D (500 IU/kg/day), or DPZ + Vit D starting from the 10th week of CuSO4 intake. Another six rats were used as normal control (NC) group. The hippocampal tissue content of β-amyloid precursor protein cleaving enzyme 1 (BACE1), phosphorylated Tau (p-tau), clusterin (CLU), tumor necrosis factor-α (TNF-α), caspase-9 (CAS-9), Bax, and Bcl-2 and the cortical content of acetylcholine (Ach), acetylcholinesterase (AChE), total antioxidant capacity (TAC), and malondialdehyde (MDA) were measured. Cognitive function tests (Y-maze) and histopathology studies (hematoxylin and eosin and Congo red stains) and immunohistochemistry for neurofilament. Vit D supplementation alleviated CuSO4-induced memory deficits including significant reduction hippocampal BACE1, p-tau, CLU, CAS-9, Bax, and TNF-α and cortical AChE and MDA. Vit D remarkably increased cortical Ach, TAC, and hippocampal Bcl-2. It also improved neurobehavioral and histological abnormalities. The effects attained by Vit D treatment were better than those attained by DPZ. Furthermore, Vit D boosted the therapeutic potential of DPZ in almost all AD associated behavioral and pathological changes. Vit D is suggested as a potential therapy to retard neurodegeneration. [ABSTRACT FROM AUTHOR]

This work was carried out to monitor contamination levels of twelve heavy metals (HMs) in the agricultural soils of Kafr El-Zayat city in Egypt. The concentrations of Mg, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Sr, and Pb were determined using inductively coupled plasma optical emission spectroscopy (ICP-OES). Contamination levels were estimated based on various geochemical parameters such as contamination factor (CF), enrichment factor (EF), geo-accumulation index (Igeo), degree of contamination (Cd), and pollution load index (PLI). The results showed that the majority of investigated soil samples were moderately contaminated (1 ≤ CF < 3) with V, Cr, Co, Cu, Zn, and Sr and had low contamination levels (CF <1) with Mg, Mn, Fe, Ni, and Pb. All investigated elements had geo-accumulation indices smaller than zero indicating uncontaminated soil samples except for V which showed (0 < Igeo < 1) indicating uncontaminated to moderate pollution levels. All soil samples were found to have deficient to minimal enrichment for all investigated HMs based on the average values of EF (EF < 2). Cluster analysis (CA) and principal component analysis (PCA) revealed that HMs were clustered into three groups compromising As and V; Ni, Cr, Mn, Co, Fe, and Mn; and Pb, Cu, Sr, and Zn, which suggests the presence of different sources of pollution. The contribution of anthropogenic sources to V, Cr, Co, Cu, Zn, As, and Sr was estimated to be 45, 30, 26, 11, 23, 27, and 13% of the total metal content, respectively. In general, the investigated agricultural soil samples could be classified as moderately contaminated and polluted based on the Cd factor (Cd = 13.7), and the PLI (PLI = 1.1), respectively. [ABSTRACT FROM AUTHOR]

Several diagnostic measures have been employed to precisely detect the SARS-CoV-2 viral infection using viral antigens, nucleic acids, and other serological approaches. The sensitivity and specificity of the serological tests remain a challenging need. Here, we describe the detection of human anti-SARS-CoV-2 IgG and IgM antibodies qualitatively through two optimized in-house ELISA and lateral flow immunoassay. Both approaches are based on the prokaryotic expression of 50 kDa SARS-CoV-2 recombinant nucleocapsid protein. This SARS-CoV-2rN-6×His was used either to coat ELISA plates or to be conjugated to gold nanoparticles followed by colorimetric detection of bound human IgG or IgM. In the LFA, we show the optimization of nanoparticle size, protein-binding capacity, membrane treatment, and finally testing the potential capacity of using either the optimized ELISA or LFA in detecting antibodies raised against viral infection. Assessment of both methods was carried out using human sera-positive and negative SARS-CoV-2 antibodies. The ELISA and LFA tests showed 86%, 96.5% sensitivity, 92%, 93.75% specificity, 97%, 98.2% PPV, and 64%, 88.2% NPV, respectively. In conclusion, both approaches were able to successfully detect human antibodies against SARS-CoV-2 nucleocapsid protein. The importance of both protocols cannot be overstated in the detection and diagnosis of viral infections, especially in developing countries. [ABSTRACT FROM AUTHOR]

Lung infiltrates are frequently observed in patients with COVID-19 infection and require specialized management. Identifying reliable laboratory parameters to reduce the need for chest CT scans in non-desaturation patients is of great interest. This study aimed to investigate the potential of C-reactive protein (CRP) as an indicator to identify the presence of lung infiltrates in early COVID-19 infection. The study was conducted at Al-Azhar University hospitals from May 2021 to March 2022 and included 210 patients with COVID-19 infection confirmed by positive PCR, all of whom were previously healthy, non-smokers, and non-hypoxemic. CRP levels were assessed and correlated with lung infiltrates observed in CT chest examinations. The mean value of CRP was 40.3±14.3 mg/L in males and 36.6±15.2 mg/L among females. One hundred sixty-two patients had pneumonic infiltrates, while 48 had no infiltrates. The mean value of CRP was 45.02±10.2 mg/L in patients with radiological infiltrates and 18.8±7.8 mg/L in patients without radiological infiltrates. Based on our findings, a CRP value greater than 29.8 mg/L was suggested as a cut-off value to indicate the presence of lung infiltrates. CRP is a simple laboratory marker that, at certain limits, may point to the presence of pneumonic infiltrates in early non-hypoxemic patients with COVID-19 infection. [ABSTRACT FROM AUTHOR]

Aromatic plants are considered sources of antioxidants, antimicrobial and favouring agents. Four aromatic plants (Thymus vulgaris L., Foeniculum vulgare, Pimpinella anisum L. and Trigonellafoenum-graecum L.) were analysed in the study. Yoghurt was used to produce a low calorie pie. Chemical and rheological parameters, baking performance, staling rate and sensory properties of the pie were investigated. Volatile aroma compounds were anal-ysed with GC and GC/ MS, and antioxidant activity was evaluated by DPPH and β-carotene assays. The incorporation of yoghurt and some aromatic plants in the pie improved protein, fat, fibre, ash, and minerals contents and allowed achieving about 19% reduction in calories. Sensory evaluation of pie containing the mixture of aromatic plants showed its superior sensory quality. In addition, it could be concluded that aromatic plants were able to inhibit the growth of yeast, mould and bacteria and to prolong the storage periods of pie compared with the control.