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Cement mortar without fibers might crack due to shrinkage or volume changes. Cracking in cement mortar leads to elastic deformation. The development of these cracks causes elastic deformation of cement mortar. This study examined the influence of two steel fibers' geometrical forms (crimped and hooked with just one end) in different amounts by volume (Volume fraction = 0.25%, 0.5%, and 0.75%) on the cement mortar's mechanical features. Among the characteristics were splitting, compressive as well as flexural strength. The samples were prepared, poured into cubic molds for compressive strength testing cylindrical molds used for splitting strength testing, and prismatic molds for flexural strength testing, and processed at various times 3, 14, and 28 days before the tests. According to the findings, the highest increase was obtained after adding 0.75% of crimped fibers, the compressive strength increased by 13.3 %21.29%, and 44.8%, for 3,14.28 days respectively, and split tensile strength increased by 66.17%,68.9%, and 79.48% for 3.14 and 28 days respectively and flexural strength increased by 72 %,91% and 92% for 3.14 and 28 days, respectively.

Information about the ecology and lifestyle of bats (Chiroptera) in Algeria is scarce. In this paper, we present the results of an inventory study of Chiroptera fauna in the Chebket ES-Sellaoua Mountains in Eastern Algeria, conducted between January 2014 and December 2015. Surveys were carried out in 10 caves throughout the region by means of a visual survey and animal captures. Five species were detected: Rhinolophus ferrumequinum, Rhinolophus hipposideros, Myotis punicus, Miniopterus schreibersi and Pipistrellus kuhli, belonging to three families: Rhinolophidae, Miniopteridae and Vespertilionidae.. Data published in Mendeley (doi:10.17632/vh83vg9n9j.2).

For a long time, limestone has been massively used in stone building and monuments because of its easy extraction and common presence in the landscape. On ancient monuments, mostly built in urban areas, it is exposed to urban-borne pollutants responsible for specific alteration mechanisms and weathering kinetics. Especially, the dissolution of calcite and the precipitation of new phases will affect the limestone pore network, modify the stones capillary properties, and influence the further alteration. In order to better understand these processes, an altered limestone sample from 'Tribunal Administratif' (TA) in Paris was studied. The main secondary phase was found to be syngenite, which can be explained by the location of the sample close to the soil, a potential source of K (fertilizers). This phase is more soluble than gypsum that is commonly found on altered limestone. In order to assess the reactivity of the system (limestone and new phases), oxygen and hydrogen isotopes were used to trace the transfer of water (D 2 18 O) and identify the location of the reactive areas (susceptible to alteration). For that, TA samples were exposed in a climatic chamber to relative humidity (RH) cycles (25% RH for 2.5 days and 85% RH for 4.5 days) for 2 months with a D 2 18 O vapor to simulate alteration occurring in conditions sheltered from the rain. Results have shown that the water vapor easily circulates deep in the sample and reacts preferentially with syngenite the most reactive phase (compared with calcite and quartz). This phase could evolve in gypsum when exposed to an environment different from the one resulting in its formation.

Objectives: It is urgent to develop non-pharmacological interventions or multifactor combination approaches to combat Alzheimer's disease (AD). The effect of exercise (EX) combined with environmental enrichment (EE) on behavioral phenotypes and neurogenesis markers in an Alzheimer-like rat model was investigated., Materials and Methods: The groups consisted of AD, sham-operated, AD+EX, AD+EE, and AD+EX+EE. AD was produced by injection of amyloid-beta (1-42, 6 µg) intrahippocampally, and a daily treadmill for 3 consecutive weeks was used for EX animals. EE was a large cage (50× 50× 50 cm) containing differently shaped objects. Spatial learning and memory were evaluated in the Morris water maze (MWM), and a shuttle box was used to evaluate inhibitory avoidance memory. RT-PCR was performed to assess the expression of early neurogenesis markers, DCX, and Sox2 within the hippocampus., Results: Pretreatment with exercise and EE, both individually and in combination, could provide protection from memory impairments in AD rats. Combined treatment led to a significantly more pronounced improvement in memory deficits of AD rats than either paradigm alone. Combination therapy with exercise and EE could also reverse the passive avoidance memory impairment and hippocampal DCX expression of AD rats to the control levels., Conclusion: These data suggest that exercise in combination with cognitive engagement can provide a non-pharmacological and multidomain policy that may prevent or delay AD symptoms., Competing Interests: The authors declare no conflicts of interest.

The behaviour of stepped bars of different materials when impacted longitudinally by mild sphere of different radii was investigated. The passage (or propagation) of the longitudinal stress wave, created from the impact, from one end to another was recorded by strain gauges positioned at various stations along each bar. Different bar combinations with Lagrangian (material) and Eulerian (geometrical) discontinuities were investigated both experimentally and theoretically. Space – time diagrams which demonstrate the stress wave traversals across the discontinuity were constructed. The theoretical analysis of stress wave propagation in solids using the well-established Rayleigh acoustic equations assuming plane sections remain plane, was discussed, and the results were compared well with the experiments. It was noted that a pulse travelling along a bar with a discontinuity, either in cross sectional area or material difference, will be subjected to amplification or attenuation as it passed through this discontinuity. The amount of change in amplitude was governed by the impedance ratio of the input to output bars. However, the reflected part of the pulse from the discontinuity was always attenuated, with the pulse sign governed by the impedance ratio. [ABSTRACT FROM AUTHOR]

An experimental chamber (CIME2) has been specially designed to simulate wet atmospheric deposition on limestones used in Paris cultural heritage. This instrument is a complementary tool to CIME, a previously developed chamber dedicated to the simulation of dry atmospheric deposition on monuments and artifacts. The aim of this paper is to describe CIME2 and characterize the wet deposits produced inside it. Mist (fog), drizzle, and rainfall are differentiated in order to document their ability to saturate the limestones most currently used in Paris monuments: The Saint-Maximin's limestone, the Liais of Saint-Maximin, and the Chauvigny's limestone are tested. The comparison between normalized and environmental petrophysical data shows that in the wet deposition simulations, limestones are not systematically water-saturated. Moreover, the realistic experimental conditions chosen favor a more rapid evaporation of the stone water. The quantification of the non-saturation state is a first step that has to be taken into account to improve the geochemical models used to predict the alteration.

Background: The weight of evidence suggests that sleep is essential for the processes of memory consolidation and sleep deprivation (SD) impairs the retention of long-term memory in both humans and experimental animals, which is associated with oxidative stress damage within the brain. Green tea polyphenols have revealed carcinogenic, antioxidant, anti-, and anti-mutagenic properties. We aimed to investigate the possible protective effect of green tea extract (GTE) and its main active catechin, epigallocatechin-3-gallate (EGCG), on post-training total sleep deprivation (TSD) -induced spatial memory deficits and oxidative stress profile in the hippocampus of the rat., Methods: Male rats were treated with saline, GTE (100 and 200 mg/kg/day), and EGCG (50 mg/kg/day) intraperitoneally for 21 days and then trained in Morris water maze (MWM) in a single day protocol. Immediately after the end of MWM training, animals were sleep deprived for 6 h by the gentle handling method, and then evaluated for spatial memory. Hippocampal levels of malondialdehyde, (MDA), and thiol was assessed as oxidant and antioxidant markers., Results: Spatial memory was impaired in the TSD group and GTE at the dose of 200 mg/kg/day as well as EGCG at the dose of 50 mg/kg/day could reverse the impairment to the saline-treated levels. Despite the unchanged MDA levels, hippocampal total thiol was significantly decreased after TSD and EGCG increased it to the basal levels., Conclusion: In conclusion, green tea and its main catechin, EGCG, could prevent memory impairments during 6 h of TSD; probably through normalizing the antioxidant thiol defense system which was impaired during TSD., Competing Interests: The authors declare no conflict of interest., (© 2021 The Author(s).)

Objectives: Cognitive decline is one of the most prevalent health problems and is associated with increased healthcare utilization and economic burden. Physical and cognitive training both have positive effects on cognition but have been less applied in combination. We hypothesized that simultaneous cognitive-physical components would yield greater cognitive benefits than single-domain interventions in rats., Methods: A total of 40 male Wistar rats were divided into four treatment groups: the control, enriched environment (EE), exercise (EX), and EE + EX. Animals in EE groups housed in the large cages (50 × 50 × 50 cm) contained differently shaped objects for 3 weeks. EX animals were forced to run on a treadmill once daily for 3 consecutive weeks. Morris water maze test was used for the assessment of spatial learning and memory. Real-time PCR was performed to assess the expression of nestin, and Sox2 in the hippocampus., Results: EX and EE animals separately did not show a significantly enhanced function in spatial memory in comparison with the control group. When animals were treated with EE and EX simultaneously, they exhibited significantly superior performance in spatial memory than control, EX, or EE groups separately. The hippocampal expression of Sox2 was significantly higher in EE + EX group than in the control, EX, and EE alone., Conclusions: These results may have clinical implications for behavioral interventions in conditions with cognitive deficiencies., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Northwick Park Hospital in London, United Kingdom (UK) is one of the busiest stroke units in the country and is located in one of the areas most heavily affected by the COVID-19 pandemic in the first half of 2020. Admissions to the stroke unit and changes during the peak of COVID-19 were reviewed. Compared with the previous year, mean 96 patients were admitted with suspected stroke during April and May 2020 compared with mean 116 per month in non-COVID periods, ratio 0.82, P = 0.01. This reduction involved both strokes and mimics and was unlikely to have occurred by chance. Numbers of patients thrombolysed and of patients referred for thrombectomy decreased dramatically during this time. Mechanisms by which the COVID-19 pandemic and the March lockdown may have affected admissions to the unit are discussed. Reduced admissions to the stroke unit allowed it to contribute its resources to the care of patients with COVID-19 during the peak of admissions., Competing Interests: Declaration of Competing Interest None., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Objectives: The purpose of this study was to provide appropriate preoperative supportive conditions to improve anxiety and vital signs for patients undergoing Coronary Artery Bypass Grafting -CABG- surgery., Methods: This clinical trial study was performed on 90 patients undergoing CABG surgery in Farshchian Hospital of Hamadan, Iran in 2019. Sample was selected by convenience and were randomly divided into three groups: control (n=30), intervention1 (n=30), and intervention2 (n=30). The control group received only the routine preoperative counseling of ward and admitted to the operating room as usual; the intervention1 and intervention2 groups in addition received another two counseling sessions, then the intervention1 group was admitted in the operating room as usual, but the intervention2 group was admitted by the counselor in the operating room. Data were collected using a three-part questionnaire including demographic characteristics, vital signs chart, and the Spielberger's State-Trait Anxiety Inventory., Results: The results showed that there was a significant difference in the mean anxiety of the three groups after admission in the operating room (intervention2 was lower than intervention1 and control groups, p<0.001; and intervention 1 group was lower than control group, p<0.001) and also there was a significant difference between the mean systolic blood pressure, heart rate and respiratory rate of the three groups (p <0.001) but the mean of the variables of temperature and diastolic blood pressure in the three groups were not significantly different (p=0.59 and p=0.225, respectively)., Conclusions: Our results revealed preoperative consultation and admission in the operating room by the consultant can reduce the level of anxiety and stability of vital signs of patients undergoing CABG., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright by the Universidad de Antioquia.)