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Цель. Проверка адекватности разработанной экспериментально-статистической математической модели по прогнозированию значения кратности воздушно-механической пены в зависимости от геометрических параметров оросителя и определение характеристик орошения оптимального по кратности пены оросителя. Методы. Определение характеристик орошения осуществлялось эмпирическим методом – путем проведения лабораторных и комплексных испытаний в реальных условиях. Результаты. Опыты по определению кратности генерируемой оросителем пены показали достаточную степень сходимости результатов экспериментов с предсказанными при помощи математической модели значениями (отклонение не более 16,1 %). Экспериментально получены значения кратности генерируемой оптимальным оросителем пены в диапазоне от 11,2 до 13,6, что на 60–94 % больше, чем у используемых на данный момент оросителей розеточного типа. Для оптимального по кратности пены оросителя при проведении комплексных испытаний установлены характеристики орошения (защищаемая площадь, интенсивность и равномерность орошения). Определены дальнейшие пути повышения эффективности оросителя при пожаротушении. Область применения исследований. Полученные результаты могут быть использованы при конструировании пенных оросителей для автоматических установок пожаротушения с повышенной эффективностью работы.

In order to predict volume changes of Nb 3 Sn coils during reaction heat treatment (RHT), coefficients of thermal expansion (CTE) of the involved materials need to be known. While the CTEs of bulk materials are widely available, there is a lack of knowledge about the dimensional changes of the Nb 3 Sn Rutherford cables. By extensometry we have measured the length changes of 11 T dipole Nb3Sn Rutherford cables during the RHT. Similar to the length change behavior of multifilament wires, after an initial cable length increase the cable length decreases when the temperature exceeds about 150 °C, due to relaxation of the Nb subelements when the Cu matrix is annealed. At higher temperatures the cable length increase is determined by the CTE of the unreacted Nb, before the onset of Nb 3 Sn formation leads to an increased expansion rate. During cooling, the thermal contraction of fully reacted Nb 3 Sn cable is similar to that of Nb 3 Sn bulk.

This article reviews recent progress in semi-arid climate change research in China. Results indicate that the areas of semi-arid regions have increased rapidly during recent years in China, with an increase of 33% during 1994-2008 compared to 1948-62. Studies have found that the expansion rate of semi-arid areas over China is nearly 10 times higher than that of arid and sub-humid areas, and is mainly transformed from sub-humid/humid regions. Meanwhile, the greatest warming during the past 100 years has been observed over semi-arid regions in China, and mainly induced by radiatively forced processes. The intensity of the regional temperature response over semi-arid regions has been amplified by land-atmosphere interactions and human activities. The decadal climate variation in semi-arid regions is modulated by oceanic oscillations, which induce land-sea and north-south thermal contrasts and affect the intensities of westerlies, planetary waves and blocking frequencies. In addition, the drier climates in semi-arid regions across China are also associated with the weakened East Asian summer monsoon in recent years. Moreover, dust aerosols in semi-arid regions may have altered precipitation by affecting the local energy and hydrological cycles. Finally, semi-arid regions in China are projected to continuously expand in the 21st century, which will increase the risk of desertification in the near future.

One of the best ways to increase the fiber content in the diet is supplementing wheat bran in bread. Wheat bran is known to affect the cellular structure of the dough, resulting in lower final bread volume. The present study was focused on analyzing the effect of wheat bran in throughout the bread making process; the results were compared with the recipe without bran. Wheat bran at different level viz., 0%, 8%, 16% and 24% w/w on flour basis was added into the wheat flour for the preparation of sandwich bread. Results showed that wheat bran significantly (p 0.05) affected the dough kneading parameters. Dough properties like stickiness and extensibility decreased with respect to increase in bran quantity. Unexpectedly, wheat bran enhanced the aeration of dough during mixing and the expansion rate of dough during fermentation. However, wheat bran decreased the specific volume of bread upto 10.81%, which was confirmed using 2D image analysis method where it was observed as the wheat bran alters the pore size distribution in bread crumb.

ANFO is a well-known, reliable and safe commercial explosive. It has been around since the late 1950's and its detonation properties are well characterized. In this study, the detonation process of dry, wet and aluminised ANFO, was recorded using two high-speed cameras with recording rates of 1,200 fps and 50,000 fps. The 1,200-fps footage allowed the observation of the post blast fumes (i.e. NOx) produced by ANFOs with different water contents. The 50,000-fps footage allowed the observation of the detonation area, gas expansion phase and the measurement of the velocity of detonation (VOD). The video footage also recorded a bright zone in front of the gases (longer than 50 mm). We assumed that a reaction is taking place in this zone, but it is difficult to be sure if this is the reaction zone or not as it is longer than previously reported reaction zone lengths.Analysis showed that ANFO detonates effectively for water contents of up to 9 wt.%, and more importantly, there is little variation in the VOD. As far as the expansion of gases is concerned, the ANFO-Al expansion rate appears to be different. In this mixture, the absence of NOx fumes could have been due to the expected higher temperatures produced by the burning of the aluminium additive as observed in the images recorded with the high-speed camera.

Human mesenchymal stem cells (MSCs) are presently on the top of hierarchy in the field of stem cell therapy, due to their miraculous therapeutic abilities in diminishing the symptoms of many chronic diseases and initiating regeneration and repair for various damaged tissues and organs. The foremost initial step to reach high success rate in any MSCs based study is the optimization of culture growth media by establishing a suitable fetal bovine serum (FBS) percentage that suits the purpose of MSCs based experiment. Choosing the suitable FBS percentage is a controversial issue and merely depends on the researchers experience and suggested recommendations by the suppliers. Despite the huge improvements in overall MSCs investigating approaches, there are no definite protocols that set up a range of FBS percentages that can be followed. Toward achieving this objective, we evaluate in the present report the effect of using various FBS percentages (5-20%) added to DMEM low glucose media, on the biological behaviour of MSCs. Growing MSCs in high FBS percentages containing culture media (15% and 20% FBS) increase the proliferation and expansion rate of MSCs, although it decreases the immunosuppressive properties. On the other hand, adding low FBS percentage (7% FBS) to MSCs culture media enhanced the immunosuppression characteristics of MSCs, even though the proliferation rate was moderately reduced. 7% FBS is the cut off percentage that can be used without negatively altering major MSCs biological properties in which using 5% FBS will cause a tremendous decrease in the proliferation capacity and immunosuppressive properties. This report may assist other researchers in choosing appropriate FBS percentage when preparing MSCs culture media that serve the purpose of their MSCs based studies.

The fatigue-crack growth of the die-forged Al-5.87Zn-2.07Mg-2.42Cu alloy at different ageing conditions: peak aged (T6), over aged (T73) and retrogression and re-ageing (RRA), has been examined in the study. The RRA alloy has the highest resistance to fatigue crack initiation. With increasing stress intensity range (Δk), the T73 sample has the largest expansion rate and it is the smallest for the RRA sample. In the second stage of crack propagation, the crack-growth rate is the largest for the T6 specimen and smallest for the RRA specimen. The crack propagation mode of the alloy in different ageing conditions is mainly based on transgranular expansion. Intergranular expansion was also observed in the T73 state and significant secondary cracks were observed in the RRA sample.

The results of experimental studies on determination of the effect of the deflector-type sprinkler geometric parameters on the air-mechanical foam formation process are presented in the article. A collapsible sprinkler was developed for the experiment. The elements of the collapsible sprinkler which allow creating its various configurations in a fairly wide range of geometric parameters were made from polylactide (PLA-plastic) with the help of 3D printing. The dependencies of the air-mechanical foam expansion rate and stability on the sprinkler holder length, as well as the external diameter, the taper angle and the ledges height of the sprinkler sprayer were established. The ranges of optimal values along the holder length L = 45÷55 mm and the sprayer ledges height h = 1÷3 mm of the sprinkler for generation of foam with the greatest expansion rate and stability were determined, as well as the ranges of values of these parameters at which the change in the quality characteristics does not occur (L = 90÷150 mm, h = 5÷15 mm). A decrease in the foam quality characteristics with an increase in the sprayer taper angle of the sprinkler was established. Approximate dependencies of the foam expansion rate and stability on the sprayer taper angle of the sprinkler in the range α = 30÷135° were obtained. In addition, it is determined that an increase in the sprayer external diameter in the range from 20 mm to 100 mm results in a gradual deterioration in the foam qua lity. The results of the conducted researches will allow optimizing geometrical parameters of existing designs of deflector-type sprinklers with the aim to increase their fire extinguishing efficiency.

Glaciers in the Himalaya are increasingly retreating and thinning due to climate change. This process is the primary cause of glacial lakes expansion and has increased the possibilities of the glacial lake outburst floods (GLOFs) that have been responsible for heavy loss of life and damage to downstream infrastructures. This study examines the status of the existing potentially dangerous glacial lakes in the Nepalese Himalaya such as Imja Tsho, Tsho Rolpa, Thulagi, Chamlang South, Barun Tsho, and Lumding Tsho; which were more susceptible to GLOF after the devastating earthquake in 2015. We examined the evolution and decadal expansion rate of lakes from 1987 to 2016 using Landsat images. The results show significant expansion of Imja Tsho, Barun Tsho, and Lumding Tsho at the rates of 42.1, 46.8, and 32.9% respectively, during 2006 - 2016; while other glacial lakes (i.e., Chamlang South, Barun Tsho, and Lumding Tsho) are relatively stable. Although the current status of glacial lakes may be stable in term of burst risk, high expanding lakes must be prioritized for detail studies. Continuous model-based monitoring and risk assessment, mitigation measures and disaster management strategies are necessary for reducing the impact of GLOFs.

Theoretical and experimental investigations are conducted to study the freezing process of a sessile water droplet. A novel model that considers the effects of both supercooling and gravity and assumes the freezing front (ice-water interface) to be a spherical surface is developed to simulate the droplet freezing behaviors. Two correlations describing the evolution of triple-phase line height and that of contact angle of unfrozen ice-water mixture on frozen ice are developed to close the model, with their concrete expressions being determined by combining the theory and experiment. Experiments are conducted on different sizes of water droplets deposited on cold aluminum plates having different contact angles and temperatures. The droplet freezing behaviors including the triple-phase line movements and droplet shape evolutions are observed and recorded using the image recognition technology. Calculations are implemented to simulate the evolution of droplet freezing shape, the movement of freezing front, the formation of pointy tip, and the variations of droplet volume and expansion rate. Comparisons are made between the calculation and experiment, and good agreements are obtained, with the calculated freezing times agreeing with the measured ones within 2%.

It is shown with several concrete examples that the Dyer-Roeder approximation is valid in spacetimes which fulfill the condition that fluctuations in the expansion rate along a light ray locally cancels with the shear contribution to the redshift. This is the case for standard cosmological scenarios including perturbed FLRW spacetimes, N-body simulations and Swiss-cheese models. With another concrete example it is then illustrated that it is possible to construct statistically homogeneous and effectively statistically isotropic cosmological models which do not fulfill the condition. In this case, the Dyer-Roeder approximation is invalid. Instead, the mean redshift-distance relation can be described using a relation based on the spatial averages of the transparent part of the spacetime., 15 pages, 11 captioned figures. Accepted for publication in PRD

This paper studies the influence of assembly unit of expansive agents (CaO and calcium sulphoaluminate) on the limited and free compressive strengths, the limited expansion rate, carbonation resistance, chloride ion penetration resistance and corrosion resistance of reinforcement concrete. The dosages of expansive agent were 0%, 3%, 6%, 9%, and 12% by the total amount of cementitious materials. Two kinds of mineral admixture (blast furnace slag and fly ash) were applied in this study. Results show that suitable dosage (lower than or equal to 9%) of double expansion agent with a large amount of mineral admixtures can improve the limited and free compressive strengths. However, when the dosage of the double expansion agent is higher than 9%, the addition of the double expansion agent leads to the reduction of limited and free compressive strengths. The variation of the limit expansion rate reaches the maximum value when the curing age is 14 days. The increasing addition of expansive agents and lower water-binder ratio demonstrate positive effect on the limited expansion rate. Concrete with 60% mineral admixtures (fly ash and ground granulated blast furnace slag) shows lower limited expansion rate and higher compressive strength than the concrete with 50% mineral admixtures. Finally, the incorporation of double expansion agent can improve the resistance to carbonation, chloride ion penetration resistance, anti-corrosion of steel bars and mechanical strengths (the limited and free compressive strengths).

Exploring the coordinated development process of people–land allocation in the urbanization process of urban agglomerations is of great significance to promote improvement of the urbanization development level and quality and realize the healthy development of urbanization. We took nine urban agglomerations in China as the research object and the coupling between urban expansion and population growth as the entry point. The overall coupling and the spatial coupling were used to reveal the people–land coupling relationship of nine urban agglomerations at different time periods. We found that both construction land and population within each urban agglomeration were in the stage of continuous growth, and the increase of both was similar and synchronous. The overall and spatial coupling between urban expansion and population growth is increasing. The expansion rate of construction land is a factor that influences the overall and spatial coupling between urban expansion and population growth, i.e., the greater the expansion rate of construction land, the higher the overall and spatial coupling between urban expansion and population growth. This study provides a new perspective for exploring the coupling between urban expansion and population growth and offers a new approach for studying the relationship between the two.

International audience; Carbon nanotubes (CNTs) offer attractive opportunities due to their physical, electrical, mechanical, optical, and thermal properties. They are used in a wide range of applications and are found in numerous consumer products. On the downside, their increasing presence in the environment poses potential threats to living organisms and ecosystems. The aim of this study was to evaluate the toxicity of double-walled carbon nanotubes (DWCNTs) on a new model system: the acellular slime mold Physarum polycephalum. Despite its ecological significance, its simplicity of organization, and its behavioral complexity, exposure of such organisms to nanoparticles has been poorly investigated. Slime molds were exposed to DWCNTs using three routes of exposure (topical, food, environment). We first demonstrated that DWCNTs were rapidly internalized by slime molds especially when DWCNTs were mixed with the food or spread out in the environment. Secondly, we showed that a 6-week exposure to DWCNTs did not lead to bioaccumulation nor did it lead to persistence in the slime molds when they entered a resting stage. Thirdly, we revealed that 2 days following exposure, DWCNTs were almost entirely excreted from the slime molds. Lastly, we uncovered that DWCNTs exposure altered the migration speed, the pseudopods formation, and the expansion rate of the slime molds. Our results extend our current knowledge of CNTs cytotoxicity and introduce P. polycephalum as an ideal organism for nanotoxicology.

Tensions in cosmological parameters measurement motivate a revisit of the effects of instrumental systematics. In this article, we focus on the Pearson's correlation coefficient of the cosmic microwave background temperature and polarization E modes $\mathcal{R}_\ell^{\rm TE}$ which has the property of not being biased by multiplicative instrumental systematics. We build a $\mathcal{R}_\ell^{\rm TE}$-based likelihood for the Planck data, and present the first constraints on $\Lambda$CDM parameters from the correlation coefficient. Our results are compatible with parameters derived from a power spectra based likelihood. In particular the value of the Hubble parameter $H_0$ characterizing the expansion of the Universe today, 67.5 $\pm$ 1.3 km/s/Mpc, is consistent with the ones inferred from standard CMB analysis. We also discuss the consistency of the Planck correlation coefficient with the one computed from the most recent ACTPol power spectra., Comment: 10 pages, 5 figures

Agriculture is the primary source of India for the raise of livestock and it's the backbone of the economy that gives surplus food materials for living and it conjointly acts as stuff for industries. India's twenty eighth percent of the national income depends on the agricultural sector. Agriculture contributes to the expansion rate of employment. The most important issue faced in agriculture is loss or damage of crops due to environmental conditions such as flood, lack of water during summer and various pests which affects the crops. Among these crop diseases and pests have an enormous contribution to agricultural huge loss. The diseases can be identified with advanced deep learning algorithms. Though many DL methods works well in identifying the disease still there are misclassifications during training. To avoid the misclassification in predicting the appropriate disease an ensemble activation approach is proposed. In this paper, deep learning based technique is enforced for the automatic detection of plant leaf diseases. The convolution Neural Network approach is applied during this paper. Activation functions play a vital role in convolution Neural Network (CNN). In this paper, a combination of hybrid activation function is proposed to improve the accuracy rate of the CNN model. The hybrid Activation function is tested and trained on different datasets. The hybrid activation function is compared with the standard activation function ReLU. The Experimental results by trial and error show that the hybrid activation function achieves higher accuracy than the ReLU activation function.

In this letter we propose a reduction of the $H_0$ tension puzzle by means of a theory of minimally modified gravity which is dubbed VCDM. After confronting the theory with the experiments, we find that the data allow for a low-redshift transition in the expansion history of the universe at either $z\simeq 0.3 $ or $z \simeq 1.8\,$, corresponding to one of the two local minima of the total $\chi^2$. From the bestfit values the total fitness parameter is improved by $\Delta \chi^2 \simeq 12$, for the data set considered. We then infer the local Hubble expansion rate today within this theory by means of low redshift Pantheon data. The resulting local Hubble expansion rate today is $H^{\rm{loc}}_0=73.6\pm1.4$. We find the tension is reduced within the VCDM theory., Comment: 9 pages, 4 figures; minor revision in v5

The transformation law of autogenous volume deformation of MgO-admixed concrete with specimen size was revealed through continuous observation on standard-size (Φ200 mm × 500 mm), medium-size (Φ250 mm × 500 mm), and large-size specimens (Φ250 mm × 600 mm) over 6 years. Besides, the pore parameters of concrete core samples obtained from autogenous volume deformation specimens in the 1st, 3rd, and 6th years of age were investigated. The results show that the autogenous volume deformation of MgO-admixed concrete increases with the increase in the MgO content or age. The expansion rate of the concrete specimen decreases after the age of 360 days, and the autogenous volume expansion deformation of the specimen tends to be stable after about 2 years. When the size of the specimen changes, the autogenous volume deformation of MgO-admixed concrete decreases with the increase of specimen size. During the age of 2–6 years, the expansion of medium- and large-size specimens is reduced by 6–10 and 15–20%, respectively, compared with the standard-size specimens under the same MgO content. With the condition of an appropriate MgO content, regardless of the size of the specimen, the pore structure of the concrete becomes better and better with the growth of age, the concrete becomes denser and denser, and the expansion caused by MgO hydration will not cause damage to concrete structures.

Purpose: To investigate atrophy expansion rate (ER) using ultra-widefield (UWF) fundus autofluorescence (FAF) in Stargardt disease (STGD1). Design: Retrospective, longitudinal study. Participants: Patients with biallelic ABCA4 mutations who were evaluated with UWF FAF and Heidelberg 30° × 30° and 55° × 55° FAF imaging. Methods: Patients with atrophy secondary to STGD1 were classified into genotype groups: group A, biallelic severe or null-like variants with early-onset disease; group B, 1 intermediate variant in trans with severe or null-like variant; and group C, 1 mild variant in trans with severe or null-like variant or late-onset disease. The boundaries of definitely decreased autofluorescence (DDAF) were outlined manually and areas (in square millimeters) were recorded at baseline and follow-up. Bland-Altman analysis was conducted to examine agreement between observers and devices. Linear mixed modeling was used to evaluate predictors of ER in DDAF area and square root area (SRA). Main Outcome Measures: Patient and ocular predictors of DDAF area ER and DDAF SRA ER included age at onset, duration of symptoms, genotype group, baseline visual acuity, and baseline atrophy size. Results: A total of 138 eyes from 69 patients (33 men [47%]; mean age ± standard deviation, 41 ± 20 years; range, 10–83 years) carrying 61 unique ABCA4 variants were recruited. Ultra-widefield FAF measurements were equivalent to Heidelberg 30° × 30° imaging. Baseline DDAF area was the only significant predictor of DDAF area ER (P < 0.001). Age at baseline and genotype group were predictors for DDAF SRA ER. Definitely decreased autofluorescence area ER ranged from 4.65 mm2/year (group A) to 0.62 mm2/year (group C). Conclusions: Ultra-widefield FAF is a feasible and reliable method for assessing atrophy ER in STGD1. The value of ABCA4 mutation severity in predicting atrophy ER warrants further investigation.

Objective Previous studies on the relationship between positron emission tomography (PET) images and abdominal aortic aneurysm (AAA) progression have shown contradictory results, and the objective of this study was to systematically review the role of PET in predicting AAA prognosis. Data sources PubMed, Embase, and Web of Science were searched for studies evaluating the correlation between PET imaging results and AAA growth, repair, or rupture. Review methods Two authors independently performed the study search, data extraction, and quality assessment following a standard method. Results Of the 11 studies included in this review, nine used 18F-fluorodeoxyglucose (18F-FDG) PET and computed tomography (CT) imaging, whereas the remaining two used 18F-sodium fluoride (18F-NaF) PET/CT and 18F-FDG PET/magnetic resonance imaging (MRI). Findings from the 18F-FDG PET/CT studies were contradictory. Six studies found no significant association or correlation, and two studies found a significant negative correlation between 18F-FDG uptake and AAA expansion. Additionally, one study found that the 18F-FDG uptake was statistically positively related to the expansion rate in a specific AAA subgroup whose AAAs expanded significantly. Two studies suggested that increased 18F-FDG uptake was significantly associated with AAA repair, while the other studies either found no association between 18F-FDG uptake and AAA rupture or repair or failed to report the occurrence of clinical events. One PET/CT study that used 18F-NaF as a tracer showed that an increased tracer uptake was significantly associated with AAA growth and clinical events. Finally, the 18F-FDG PET/MRI study indicated that 18F-FDG uptake was not significantly correlated with AAA expansion. Conclusion A definitive role for 18F-FDG PET imaging for AAA prognosis awaits further investigation, and new PET tracers such as 18F-NaF have the potential to be a promising method for predicting AAA clinical outcomes.

New measurements of the expansion rate of the Universe have plunged the standard model of cosmology into a severe crisis. In this letter, we propose a simple resolution to the problem that relies on a first order phase transition in a dark sector in the early Universe, before recombination. This will lead to a short phase of a New Early Dark Energy (NEDE) component and can explain the observations. We model the false vacuum decay of the NEDE scalar field as a sudden transition from a cosmological constant source to a decaying fluid with constant equation of state. The corresponding fluid perturbations are covariantly matched to the adiabatic fluctuations of a sub-dominant scalar field that triggers the phase transition. Fitting our model to measurements of the cosmic microwave background (CMB), baryonic acoustic oscillations (BAO, and supernovae (SNe) yields a significant improvement of the best-fit compared with the standard cosmological model without NEDE. We find the mean value of the present Hubble parameter in the NEDE model to be $H_0=71.4 \pm 1.0 ~\textrm{km}\, \textrm{s}^{-1}\, \textrm{Mpc}^{-1}$ ($68\, \%$ C.L.)., 6 pages, 2 figures, 1 table, v4: corrected BOSS likelihood in MontePython, v5: matches version published in PRD Letters (selected as Editors' suggestion)

We measure the expansion rate of the recent Universe and the calibration scale of the baryon acoustic oscillation (BAO) from low-redshift data. BAO relies on the calibration scale, i.e., the sound horizon at the end of drag epoch $r_d$, which often imposes a prior of the cosmic microwave background (CMB) measurement from the Planck satellite. In order to make really independent measurements of $H_0$, we leave $r_d$ completely free and use the BAO data sets combined with the 31 observational $H(z)$ data, GW170817 and Pantheon sample of Type Ia supernovae. In $\Lambda$CDM model, we get $H_0=68.63^{+1.75}_{-1.77}$ km s$^{-1}$ Mpc$^{-1}$, $r_d=146.85^{+3.29}_{-3.77}$ Mpc. For the two model-independent reconstructions of $H(z)$, we obtain $H_0=68.02\pm1.82$ km s$^{-1}$ Mpc$^{-1}$, $r_d=148.18^{+3.36}_{-3.78}$ Mpc in the cubic expansion, and $H_0=68.58\pm1.76$ km s$^{-1}$ Mpc$^{-1}$, $r_d=148.02^{+3.63}_{-3.60}$ Mpc in the polynomial expansion. The values of Hubble constant $H_0$ and sound horizon $r_d$ are consistent with the estimate derived from the Planck CMB data assuming a flat $\Lambda$CDM model, but $H_0$ is in $2.4\sim2.6$ $\sigma$ tension with SH0ES 2019, respectively., Comment: 8 pages, 5 figures, 3 tables

We consider redshift drift in a general space-time as expressed in terms of physically interpretable multipole series. An important realisation from the derived results is that redshift drift cannot in general be thought of as a direct probe of the average expansion rate of the Universe due to the presence of structure along the light beams from the astrophysical sources to the observer. We also predict the general presence of a dipolar and a quadrupolar offset in the detection of redshift drift for observers placed in locally anisotropic environments., 4 pages

The stability of steel-slag road materials remains a critical issue in their utilization as an aggregate base course. In this pursuit, the present study was envisaged to investigate the effects of fly ash on the mechanical properties and expansion behavior of cement-fly-ash-stabilized steel slag. Strength tests and expansion tests of the cement-fly-ash-stabilized steel slag with varying additions of fly ash were carried out. The results indicate that the cement-fly-ash-stabilized steel slag exhibited good mechanical properties. The expansion rate and the number of bulges of the stabilized material reduced with an increase in the addition. When the addition of fly ash was 30&ndash, 60%, the stabilized material was not damaged due to expansion. Furthermore, the results of X-CT, XRD and SEM-EDS show that fly ash reacted with the expansive component of the steel slag. In addition, the macro structure of the stabilized material was found to be changed by an increase in the concentration of the fly ash, in order to improve the volumetric stability. Our study shows that the cement-fly-ash-stabilized steel slag exhibits good mechanical properties and volumetric stability with reasonable additions of fly ash.

Stirred single-use bioreactors in combination with microcarriers (MCs) have established themselves as a technology that has the potential to meet the demands of current and future cell therapeutic markets. However, most of the published processes have been performed using fetal bovine serum (FBS) containing cell culture medium and non-biocompatible MCs. This approach has two significant drawbacks: firstly, the inevitable potential risks associated with the use of FBS for clinical applications, secondly, non-biocompatible MCs have to be removed from the cell suspension before implantation, requiring a step that causes loss of viable cells and adds further costs and complications. This study aimed to develop a new platform based on a chemically defined xeno- and serum-free cell culture medium and biodegradable MC that can support the growth of human adipose stem cells (hASCs) while still preserving their undifferentiated status. A specific combination of components and manufacturing parameters resulted in a MC prototype, called &ldquo, BR44&rdquo, which delivered the desired functionality. MC BR44 allows the hASCs to stick to its surface and grow in a chemically defined xeno- and serum-free medium (UrSuppe). Although the cells&rsquo, expansion rate was not as high as with a commercial non-biodegradable standard MC, those cultured on BR44 maintained a better undifferentiated status in both static and dynamic conditions than those cultured on traditional 2D surfaces.

Measurements for the expansion rate of the universe disagree. Indeed, local measurements suggest a higher value of the Hubble constant than those performed through the cosmic microwave background. This fact led to a very interesting debate within the scientific community. The paper is not devoted to give solutions to the problem of “Hubble tension”. The aim of this paper is, on the contrary, to deduce the [Formula: see text] cosmological parameter from a theoretical point of view, using only two experimental data: the temperature of CMB today and the temperature of photons near the decoupling time.

The rapid accumulation of observed Fast Radio Bursts (FRBs) originating from cosmological distances makes it likely that some will be strongly lensed by intervening matter along the line of sight. Detection of lensed FRB repeaters, which account for a noteworthy fraction of the total population, will allow not only an accurate measurement of the lensing time delay, but also follow-up high-resolution observations to pinpoint the location of the lensed images. Recent works proposed to use such strongly-lensed FRBs to derive constraints on the current expansion rate $ H_{0} $ as well as on cosmic curvature. Here we study the prospects for placing constraints on departures from general relativity via such systems. Using an ensemble of simulated events, we focus on the gravitational slip parameter $\gamma_{\rm PN}$ in screened modified gravity models and show that FRB time-delay measurements can yield constraints as tight as $ \left| \gamma_{\rm PN}-1\right| \lesssim 0.04\times(\Lambda/100\rm kpc)\times[N/10]^{-1/2} $ at $1\sigma$ with $10$ detections., Comment: 12 pages, 7 figures

In this study, the bit-level table of orthogonal test is adopted as the coding form of Genetic Algorithm (GA), and a Back Propagation (BP) neural network prediction model of the basic properties of full steel slag aggregate concrete (FSSAC) is established, and the experiment data are validated with good agreement. The impacts of several parameters including the sand ratio, water-cement ratio, content of steel slag sand, replacement particle size of steel slag sand, content of coarse steel slag, and replacement particle size of coarse steel slag on the compressive strength and expansion rate of the FSSAC are numerically investigated. The results show that the compressive strength of the FSSAC declines with the increase of the sand ratio, water-cement ratio, content of the steel slag sand, or coarse steel slag while it first increases and then decreases as the replacement particle size of steel slag sand or replacement particle size of coarse steel slag increases. The expansion rate of the FSSAC increases as the sand ratio or content of coarse steel slag increases. With a gradual increase of the water-cement ratio, content of steel slag sand, replacement particle size of steel slag sand, or replacement particle size of coarse steel slag, the expansion rate of the FSSAC first increases and then decreases. In addition, the impacts of the three most important parameters (i.e., water-cement ratio, content of steel slag sand, and replacement particle size of steel slag sand) on the stress-strain relationship of the FSSAC stub columns is further numerically studied.

Type Ia Supernovae (SNe Ia) represents a distinct class of stellar objects which is crucial for cosmological applications such as estimating expansion rate of the universe and measuring the matter density at large scales. Spectroscopic and photometric observations (Light Curves) are used to identify these objects. Recent studies indicate heterogeneity among SNe Ia which is a vital issue for cosmological studies. We investigate the existence of subgroups within SNe Ia class using the photometric properties such as decline rate of light curve and the position of SN in the host galaxy. For this study, a sample of 40 SNe Ia from Asiago Supernova Catalogue and Calan/Tololo survey is taken. Density Based Spatial Clustering of Applications with Noise (DBSCAN) algorithm is implemented on the data sample. Our results show the presence of sub-groups in the SNe Ia sample. Strong correlation among various parameters of SNe Ia is found in each sub-group.

Zhao, Gong-Bo, et al., We perform a joint BAO and RSD analysis using the eBOSS DR16 LRG and ELG samples in the redshift range of z [0.6, 1.1], and detect an RSD signal from the cross-power spectrum at a ∼4σ confidence level, i.e., fσ8 = 0.317 ± 0.080 at zeff = 0.77. Based on the chained power spectrum, which is a new development in this work to mitigate the angular systematics, we measure the BAO distances and growth rate simultaneously at two effective redshifts, namely, DM/rd (z = 0.70) = 17.96 ± 0.51, DH/rd (z = 0.70) = 21.22 ± 1.20, fσ8 (z = 0.70) = 0.43 ± 0.05, and DM/rd (z = 0.845) = 18.90 ± 0.78, DH/rd (z = 0.845) = 20.91 ± 2.86, fσ8 (z = 0.845) = 0.30 ± 0.08. Combined with BAO measurements including those from the eBOSS DR16 QSO and Lyman-α sample, our measurement has raised the significance level of a non-zero ωΛ to ∼11σ. The data product of this work is publicly available at https://github.com/icosmology/eBOSS_DR16_LRGxELG and https://www.sdss.org/science/final-bao-and-rsd-measurements/., GBZ is supported by the National Key Basic Research and Development Program of China (No. 2018YFA0404503), and a grant of CAS Interdisciplinary Innovation Team. GBZ, YW, and WBZ are supported by NSFC Grants 11925303, 11720101004, 11673025, and 11890691. YW is also supported by the Nebula Talents Program of NAOC and by the Youth Innovation Promotion Association CAS. EMM has received funding from the European Research Council (ERC) under the European Unions Horizon 2020 research and innovation programme (grant agreement no. 693024).

Maximum power point tracking (MPPT) controllers achieve higher importance due to the high expansion rate of photovoltaic systems. The probability of partial shading conditions (PSCs) is also increased which drastically reduced the maximum power extraction capability from PV systems. In this paper, different types of MPPT algorithms using direct control method have been examined under the same test conditions. The current research trend on MPPT controllers has also been highlighted. This paper gives a brief description to engineers and practitioners working in the area of MPPT controllers.

The western region of China is rich in mineral resources. The vigorous development of mineral resources has exacerbated the environmental and safety problems in the region. One of the important links to solve this problem is to control the development laws and distribution characteristics of the overburdened cracks in the mining of this area. In this paper, the Xiashijie coal mine 3-2 coal seam and 4-2 coal seam are examples of repeated mining, and are examined as the background, through theoretical analysis to optimize the size of the coal pillars in the lower section, using the 3DEC numerical simulation experiment method and the rise of the cracks in the short-distance coal seam. Repeated mining monitoring and analysis of the development law are used to ascertain distribution characteristics of overburdened cracks caused by the repeated mining process of the working face. The results show that: (1) By establishing a mechanical model of the overlying strata structure under short-distance coal seam group mining, and carrying out the force analysis of the double section coal pillar under repeated mining, the reasonable size of a lower section coal pillar was determined to be 70 m. (2) As the development height of a fracture progresses with the working face, its expansion rate undergoes four obvious changes: fluctuations within a certain range, the expansion rate reaches the peak after the rock formation is concentrated and broken, the cyclical change gradually decreases, and the expansion rate is zero after complete mining. (3) The fracture zone height of 222 and 224 face under repeated mining in the 4-2 coal seam was 19.56&ndash, 22.31 times and 22.38&ndash, 24.54 times larger, respectively, and the post-mining fracture extension of the face with larger width and deeper burial under repeated mining was higher than that of the adjacent face. This study provides scientific guidance for the rational division of coal pillars and the solution of the problem of water conservation mining under repeated mining in the adjacent face of a short-distance coal seam.

The Hubble parameter is one of the central parameters in modern cosmology, which describes the present expansion rate of the universe. Their values inferred from the late-time observations are systematically higher than those from the early-time measurements by about $10\%$. To come to a robust conclusion, independent probes with accuracy at percent levels are crucial. Gravitational waves from compact binary coalescence events can be formulated into the standard siren approach to provide an independent Hubble parameter measurement. The future space-borne gravitational wave observatory network, such as the LISA-Taiji network, will be able to measure the gravitational wave signals in the Millihertz bands with unprecedented accuracy. By including several statistical and instrumental noises, we show that within 5 years operation time, the LISA-Taiji network is able to constrain the Hubble parameter within $1\%$ accuracy, and possibly beats the scatters down to $0.5\%$ or even better., 15 pages, 6 figures

This research demonstrates a new measurement and scaling approach to constrain the estimates of methane (CH4) fluxes emitted from permafrost thaw (thermokarst) lakes. Permafrost is estimated to store about 20% of the total terrestrial carbon (C) stock. Permafrost thawing releases C in part as CH4, however, there are large uncertainties in the global CH4 budget that limit the accuracy of climate change projections. Estimating how much C is released from permafrost is critical to overcome this knowledge gap. Lake CH4 fluxes are estimated by combining direct observations, geophysical mapping and satellite remote sensing along with a scaling strategy based on lake expansion rate. This research contributes to advance the understanding of CH4 fluxes from thermokarst lakes and improve atmospheric C models.

According to the Big Bang theory, the universe is undergoing continuous expansion from its early moments till today. This is evident from the observation of the cosmic background radiation by Arno Penzias and Wilson, as well as observation of distant galaxies. Penzias and Wilson got the Nobel Prize for this discovery in 1978. The rate of expansion is given by Hubble’s law. The Hubble rate of expansion increases as the square of the temperature if all the particles are relativistic, and slightly slower if they are non-relativistic. As the universe is cooling down, this expansion rate is slowing down with time. It has been realized for almost 40 years that, if this Hubble rate represented the expansion rate from the beginning of Big Bang till now, there would be some difficulty with our understanding of the universe’s history. This led to the suggestion that there is a different expansion phase of the universe before the Hubble rate of expansion began. This is a phase of extremely rapid expansion and is called the “inflationary” expansion phase.

This study aims at synthesizing the recent invasion history of Carcinus maenas in the SW Atlantic (~20 years), particularly the northward expansion, based on available published papers, technical reports, and new field surveys. Our analyses extend the known distribution range northwards ca. 330 km. totaling ~1000 km along the Argentinean coast since its last detection in Nuevo Gulf in 2015. The expansion rate appeared to slow down during the last 15 years (from 115km/yr. to 30 km/yr.) as the species continues moving northwards into the transition zone between the Magellan and Argentinean biogeographic provinces (41°–43°S). In addition, a species distribution model (SDM) is provided at a much finer spatial resolution than previous studies, which accurately foresees suitable areas of invasion in the southern San Jorge Gulf, and predicts a hotspot of invasibility around 40°–33°S° if the invasion continues northward. Potential impacts of C. maenas on native species, particularly economically important oyster beds are discussed.

We perform a multi-tracer analysis using the complete Sloan Digital Sky Survey IV (SDSS-IV) extended Baryon Oscillation Spectroscopic Survey (eBOSS) DR16 luminous red galaxy (LRG) and the DR16 emission line galaxy (ELG) samples in the configuration space, and successfully detect a cross correlation between the two samples, and find the growth rate to be $f\sigma_8=0.342 \pm 0.085$ ($\sim25$ per cent accuracy) from the cross sample alone. We perform a joint measurement of the baryonic acoustic oscillation (BAO) and redshift space distortion (RSD) parameters at a single effective redshift of $z_{\rm eff}= 0.77$, using the auto- and cross-correlation functions of the LRG and ELG samples, and find that the comoving angular diameter distance $D_M(z_{\rm eff})/r_d = 18.85\pm 0.38$, the Hubble distance $D_H(z_{\rm eff})/r_d = 19.64 \pm 0.57$, and $f\sigma_8(z_{\rm eff}) = 0.432 \pm 0.038$, which is consistent with a $\Lambda$CDM model at $68\%$ CL. Compared to the single-tracer analysis on the LRG sample, the Figure of Merit (FoM) of $\alpha_{\perp}, \alpha_{||}$ and $f\sigma_8$ is improved by a factor of $1.11$ in our multi-tracer analysis, and in particular, the statistical uncertainty of $f\sigma_8$ is reduced by $11.6 \%$., Comment: 15 pages, 13 figures, 2 tables; MNRAS accepted; The BAO and RSD measurements and the covariance matrix are made available at https://github.com/ytcosmo/MultiTracerBAORSD/

The objective of this study was to evaluate the effectiveness of the surgical method of arc resection of soft-tissue nail fold combined with a shaped dressing for ingrown toenails. The surgical method involved the excision of nail fold granulation tissue and partial or total nail avulsion with preservation of its matrix. This surgical approach was applied to 20 consecutive patients (age range, 11–30 years) admitted to the hospital from January 1, 2014, to December 31, 2015. For assessment of the method, the operative technique, dressing change, and postoperative wound healing were recorded by photography. Finally, we evaluated the therapeutic effects by calculating the recurrence rate and nail groove expansion rate. Twenty patients with 38 surgical sites in 26 toes were analyzed; there was no recurrence at 3, 6, and 12 months. There was a statistically significant difference in the groove expansion rate at different time points. We measured the wound distance on postoperative day 1 compared with the day of healing and found that the method of shaped dressing could expand the nail groove by more than 50% (P ≤ .05). The mean ± SD recovery time was 15.1 ± 2.4 days. Arc resection of the nail folds for ingrown toenails coupled with preservation of its matrix minimizes trauma and is easy to manipulate. Applying a shaped dressing after the operation further reduces the risk of recurrence and ensures enough growth space for the toenails.

This test method covers the laboratory determination of the expansion rate of concrete cores (designated as “residual expansion potential” in the following context) extracted from structures affected by alkali silica reactions.

In this study, the characteristics of the alkali-silica reaction (ASR) expansion of steel slag itself, mortar bars, and concrete specimens using steel slag as aggregate are individually investigated by the expansion test method, to determine if steel slag aggregate in concrete can provide volume stability. The results show that when steel slag is aged in water for one month, its self-expansibility is below the permitted limit of 1.5% according to the JIS A 5015 standard. The ASR test results show that the ASR expansion of the mortar bars continuously increased with the increase in the test period. However, all mortar bars were below the permitted limit of 0.1% after 14 days according to the ASTM C 1260 standard. In contrast, the ASR expansion of concrete specimens was above the criteria prescribed by the ASTM C 1293 standard. From the results, the expansion of concrete specimens could not be controlled within the permitted limit by the ASTM 1293 criteria, even if the expansivity of steel slag did not exceed the criteria. Meanwhile, considering the crack propagation patterns of the concrete specimens, the cracks due to ASR expansion developed and connected even when the expansion was below the permitted limit. Besides, when mineral admixtures were used as the binder in the concrete specimens, there were discrepancies in the results between the expansion rate and the crack properties, such as maximum length and total crack length. Therefore, to accurately determine the change in volume due to ASR expansion in concrete using steel slag as coarse aggregate, it is necessary to check the crack patterns in addition to evaluating the expansion rate.

The aim of the study was to compare the clinical and cone-beam computed tomography features of orthokeratinized odontogenic cysts (OOCs) and odontogenic keratocysts (OKCs) and to fully understand features of these 2 odontogenic cysts.This retrospective cross-sectional study included patients with mandibular OOCs and OKCs. The predictor variables included age at the time of diagnosis, sex, anatomical location of the cysts, lesion size, cortical bone expansion rate, and presence of cortical bone destruction, impacted tooth, tooth displacement, and root resorption. The outcome variable was the type of cystic lesion. A 1-way analysis of variance test was used to analyze the differences among the cases of OOCs and OKCs. The specificity and sensitivity of the radiological features were calculated to differentiate OOCs from OKCs.The sample was composed of 12 patients with OOCs and 36 patients with OKCs. The mean ages of the patients with OOCs (30.50 ± 6.14 years) and OKCs (38.39 ± 19.44 years) were concentrated in the third decade. The cystic lesions occurring in areas II and III accounted for 66.67 and 52.78% of the OOC and OKC cases, respectively. The cortical bone expansion rate of the OOC was larger than that of the unilocular OKC (OOC, 2.20 ± 1.05; OKC, 1.48 ± 0.50; P .05). The specificity and sensitivity of unilocular or multiocular cysts to differentiate OOC from OKC were 100%, 42%, 95% confidence interval of 0.1479 to 0.3892 (P .05) and tooth displacement were 100%, 3%, 95% confidence interval of 0.1479 to 0.3892 (P .05).The results of this study suggest clinical and radiological features of OOCs and OKCs mostly overlap, but OOC has distinctive characteristics. Most cystic lesions of OOC are unilocular cysts, rarely accompanied by tooth displacement. The cortical bone expansion rate is larger than that of unilocular cysts of OKC.

Meshed skin grafting is a common technique in operations to minimize surgery on the donor site area. However, the donor site area is empirically determined by surgeons due to the lack of a reliable formula to calculate the donor area required to cover a skin defect. To determine the minimal size for donor skin, the expansion rates of 1.5:1, 3:1, and 6:1 meshed skin graft and the area actually covered by them were investigated in real-world operations. About 51 patients who received 57 operations with meshed skin grafts were enrolled in this study. The average clinical coverage rates of area in cases in which 1.5:1, 3:1, or 6:1 meshed skin grafting was performed were 1.02, 1.29, or 2.18, respectively. Those rates were notably low when recipient sites were concave. The average expansion rates of 1.5:1, 3:1, and 6:1 meshed skin grafts were about 1.16, 1.61, and 2.32, respectively. These results indicate that the size of donor skin should be about 85%, 60%, and 45% size of the recipient site to achieve the target 1.5:1, 3:1, and 6:1 meshed skin graft, respectively. In addition, the donor area should be adjusted in consideration of the shape of the recipient sites.

We demonstrate the existence of sudden, finite-time, singularities, with constant scale factor, expansion rate and density, in expanding Bianchi type IX universes with free anisotropic pressures. A new type of non-simultaneous anisotropic sudden singularity arises because of the divergences of the pressures, which may be of barrel or pancake type. The effect of one or more directions of expansion hitting a sudden singularity is tantamount to dimensional reductions as the non-singular directions continue expanding and can see the sudden singularity in their past., Comment: 8 pages, no figures, pdf problem corrected

An early dark energy component consisting of a cosmic pseudo Nambu-Goldstone boson has been recently proposed to resolve the Hubble tension -- the four-sigma discrepancy between precision measurements of the expansion rate of the universe. Here we point out that such an axion-like component may be expected to couple to electromagnetism by a Chern-Simons term, and will thereby induce an anisotropic cosmic birefringence signal in the polarization of the cosmic microwave background (CMB). We show that observations of the rotation-angle power spectrum and cross-correlation with CMB temperature anisotropy can confirm the presence of this early dark energy component. Future CMB data as expected from the CMB-S4 experiment will improve sensitivity to this effect by two orders of magnitude and help in discriminating between different Hubble tension scenarios., Comment: 6 pages, 2 figures

In the sealing performance test of the hydraulic hose, it is necessary to inject a certain pressure of gas into the hose and hold the pressure for a certain period of time, and judge whether there is a leak by the pressure difference between the two ends of the hose. Since the hose will expand under the action of the internal gas pressure, the outlet pressure will be lower than the inlet pressure, and it is impossible to directly determine whether the hose is leaking. In this paper, by establishing a hydraulic hose model with a diameter of 19mm, using finite element software to simulate the pressure holding process of the hose, observe the radial deformation and volume change of the hose in this state, and study the relationship between the expansion rate of the inner volume of the hose and the pressure in the tube. Using this relationship, the outlet pressure of the hose under a certain inlet pressure condition can be obtained, and the outlet pressure can be compared with the actual outlet pressure to judge whether the air tightness of the hose is good.

The presence of a significant amount of gravitational radiation in the early Universe affects the total energy density and hence the expansion rate in the early epoch. In this work, we develop a physical model to connect the parameter of relativistic degree of freedom $N_\mathrm{eff}$ with the amplitude and shape of primordial tensor power spectrum, and use the CMB temperature and polarization data from {\it Planck} and BICEP2/KECK Array, and the primordial deuterium measurement from damped Lyman-$\alpha$ (DLA) systems to constrain this model. We find that with this extra relation $\Delta N_{\rm eff}(r,n_{\rm t})$, the tensor-to-scalar ratio $r$ is constrained to be $r, Comment: 12 pages, 7 figures