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The presence of genetically modified organisms (GMOs) in food and feed products is regulated in many countries. Various countries have issued labeling threshold levels to supervise GMO commercialization, and efficient detection methods to quantify GMO contents are critical to meet labeling regulations. The aim of this study was to develop event-specific methods to measure the event-specific/lectin gene (Le1) copy number ratio in soybean using droplet digital PCR (ddPCR), which is a recently developed technology that offers high accuracy. Duplex ddPCR methods were developed and optimized using a central composite design for the five most widely authorized GM soybean events, in which the target gene was labeled with one fluorescent reporter and the endogenous gene with another. The methods produced specific results, and the performance complied with international GMO labeling regulations. Further, the duplex ddPCR methods are compatible with chip-based digital PCR platforms and original real-time PCR, but allow higher throughput and are more sensitive in identification and quantification of these five widely authorized genetically modified soybean events.

The implementation of genetically modified organism (GMO) labeling policies requires accurate quantitative methods to measure the GMO content in test samples. A Kemingdao/phospholipase D (KMD/PLD) duplex ddPCR method was established with rice genomic DNA (gDNA) of homozygous KMD as template by optimizing the annealing temperature and cycle number. Duplex ddPCR showed a linear response over the dynamic range from 68 to 175,000 copies, covering four orders of magnitude. The limit of detection (LOD) and limit of quantification (LOQ) for duplex ddPCR were determined to be 9 copies and 34 copies of the rice haploid genome, respectively. A very high dilution factor would result in unacceptable bias and coefficients of variation for determining copy number of the gDNA solution, and more than 1000 copies of the DNA template in one reaction is preferred to obtain accurate quantitative results by duplex PCR. Five blinded DNA samples with copy number ratio of 10%, 5%, 1%, 0.1%, and 0.05%, and three blinded real-life matrix samples with mass fraction of 5%, 1%, and 0.5% were quantified by duplex ddPCR, simplex ddPCR, and qPCR. These three methods all gave comparable GMO content and copy numbers within the required precision, but the duplex ddPCR showed the narrowest uncertainty interval and provided the highest precision in comparison to simplex ddPCR and qPCR. The ddPCR is a more appealing and reliable technology for the accurate quantification of GMO content than simplex ddPCR and qPCR considering the uncertainty and precision of quantitative results, the time consumption of generating droplets, and the cost of ddPCR reagents.

Atypical haemolytic uremic syndrome (aHUS) is a clinically and genetically heterogeneous condition caused by a complex interplay between genomic susceptibility factors and environmental influences. Pathogenic variants in the DGKE gene are recently identified in cases with infantile-onset autosomal recessive aHUS. The presence of low serum C3 levels, however, has rarely been described in cases of DGKE-associated aHUS. Molecular genetic testing was performed by a commercial next-generation sequencing (NGS) panel as well and by an in-house developed targeted NGS for DGKE gene. Copy number variations (CNVs) were computed from NGS data by calculating a normalised copy number ratio of aligned number of reads at targeted genomic regions against multiple reference regions of the same sample and multiple controls. We report here two such novel clinically relevant variants (c.727_730delTTGT and c.251_259delGCGCCTTC) in the DGKE gene, in two families of infantile aHUS with low serum C3 levels.

The humidified tandem differential mobility analyzer (HTDMA) is widely used to measure the hygroscopic properties of submicron particles. The size-resolved aerosol hygroscopicity κ measured by a HTDMA will be influenced by the contribution of multiply charged aerosols, but this effect on field measurements has seldom been discussed for previous field measurements. Our calculations demonstrate that the number ratio of multiply charged particles is quite considerable for some specific sizes between 100 and 300 nm, especially during a pollution episode. The presence of multiple charges will lead to a compression effect on the aerosol hygroscopicity in HTDMA measurements. Therefore, we propose a new algorithm that performs multi-charge correction of the size-resolved hygroscopicity κ, taking both the compression effect and the multi-charge number contribution into consideration. Application of the algorithm to field measurements showed that the relatively high hygroscopicity in the accumulation size range leads to the overestimation of the hygroscopicity of particles smaller than 200 nm. The low hygroscopicity of coarse-mode particles leads to the underestimation of the hygroscopicity of accumulation particles between 200 and 500 nm in size. The difference between the corrected and measured κ values can be as large as 0.05, highlighting that special attention must be paid to the multi-charge effect when a HTDMA is used for aerosol hygroscopicity measurements.

Qualitative and quantitative detection of genetically modified products is inseparable from the application of reference materials (RMs). In this study, a batch of genomic DNA (gDNA) certified reference materials (CRMs) was developed using genetically modified rice Kemingdao (KMD) homozygotes as the raw material. The gDNA CRMs in this batch showed good homogeneity; the minimum sample intake was determined to be 2 μL. The stability study showed that transportation by cold chain is preferable, no significant degradation trend was observed during a 12-month period when storing the gDNA CRMs at 4 °C and − 20 °C, and the number of freeze-thaw cycles cannot exceed 10. The property values of the copy number ratio of transgene and endogenous gene and the copy number concentration for gDNA CRMs were determined by a collaborative characterization of eight laboratories using the duplex KMD/PLD droplet digital PCR (ddPCR) assays. The uncertainty components of characterization, potential between-unit heterogeneity, and potential degradation during long-term storage were combined to estimate the expanded uncertainty of the certified value with a coverage factor k of 2.0. The certified value of copy number ratio for KMD gDNA CRM is 0.99 ± 0.05, and that of copy number concentration is (1.76 ± 0.10) × 105 copies/μL. Compared to the gDNA CRMs in availability, this batch of KMD gDNA CRMs is assigned accurate property values and can be directly used for qualitative and quantitative detection of GMOs as well as evaluation of the parameters of analytical methods with no need of further DNA concentration measurement.

The mechanical properties of polymer composite materials used in shipbuilding are examined in this article. The samples from polymer composite materials based on glass fibers and polyester resin were made for this purpose. The manufacturing samples technique from polymer composite materials for mechanical test operation is represented here. The influence of woven roving fabric layers number ratio to the number of glass-fiber mat layers under testing samples for expansion, compression and 3 point bending has been determined by mechanical tests method. As the data processing result obtained in the experiment course it has been determined that the number of woven roving fabric layers increase with polymer composite materials increases the breaking load and tensile ultimate strength and decreases these values under compression and 3 point bending. The results obtained in this article are the basis for identifying polymer composite materials mechanical properties with different reinforcement schemes in case of their application in ship structures such as a material for transport vessels superstructure .

European anchovy (Engraulis encrasicolus L.) is one of the most abundant fish species in the Sea of Azov – Black Sea basin. Anchovy is the main commercial species in the region. In recent decades the share of anchovy catch has reached 80–85 %. The species is represented by two forms – Black Sea anchovy and Sea of Azov anchovy. One of the most important aims of modern research is to assess the state of anchovy population and to forecast its possible changes under the influence of various natural and anthropogenic factors. The results of studying the long-term (2010/11–2017/18) dynamics of the length-age structure and the intraspecific composition of anchovy wintering off the coast of the Eastern Crimea and the North Caucasus are presented. Totally 138 fish samples from trawl catches of fishing vessels were studied. Standard length of 44 202 specimens was measured with accuracy of 0.1 cm. The age of 1162 specimens was determined. Length-age key was compiled. The intraspecific identification of European anchovy was determined using otolith index (method of Skazkina). As indicators of the length-age structure, the average length and average age, distribution (number ratio of representatives of different length groups and age classes) were studied. Positive trends of the average length and the average age of anchovy were found, reflecting an increase of the proportion of large (> 9.5 cm) individuals in the population – three yearlings (2+) and four yearlings (3+). In the long-term plan the average length of the anchovy increased from 8.06 to 9.09 cm. At the same time the relative number of small (< 7.5 cm) individuals decreased almost 4 times (from 22.5 to 5.7 %), and the share of large individuals increased almost 6 times (from 5.7 to 33 %). The average age increased from 1.64 to 1.98 year. On the one hand, it was due to a nearly 3-fold reduction (from 7.1 to 2.6 %) in the relative number of young-of-the-year individuals (0+) and 1.5-fold reduction (from 72.6 to 47.7 %) of yearlings (1+). On the other hand, it was due to 2.4- and 4.3-fold increase in the relative number of three yearlings (2+) and four yearlings (3+), respectively. The appearance of abundant year class in 2013, 2014 and 2015 was the immediate reason of these changes. The intraspecific determination of the anchovy was found, Sea of Azov and Black Sea forms were identified. In the long-term plan their quantitative redistribution was shown. So, in 2010/11–2013/14 Sea of Azov form dominated in mixed wintering aggregations. Its average share was 58.5 %, with the share varying from 55 to 63 %. Average share of Black Sea form did not exceed 41.5 %, with the share varying from 37 to 45 %. However, in 2014/15 the number ratio of Sea of Azov and Black Sea forms changed to the opposite – with Black Sea anchovy dominating. Its share increased to 53 %, and in subsequent years ranged from 52 to 63 %, with average value of 56 %. The results obtained are in full accordance with the hypothesis of intraspecific structure reorganization of anchovy because of the change in climatic conditions (general regional warming). Earlier we suggested this hypothesis based on the results of research of long-term (1999–2010) structure dynamics of anchovy wintering off the western coast of Crimea. According to this hypothesis, in 1999–2004 Sea of Azov anchovy dominated in wintering aggregations with average share 66.7 % of the total number, with the share varying from 56 to 87 % in different years. The average share of Black Sea anchovy in that period did not exceed 33.3 %, with the share varying from 13 to 44 % in different years. In 2005 the ratio of two forms changed to the opposite. Black Sea anchovy dominated. In 2005–2010 its share was 76.7 % on average, varying in different years from 57 to 88 %. Apparently, the reorganization of the anchovy intraspecific structure should be considered as ecological adaptation of this species, ensuring more perfect adaptability to changing environmental conditions, in particular, to the water temperature. Sea of Azov anchovy and Black Sea anchovy are “temperature races”. Sea of Azov anchovy is resistant to lower reproductive temperature, Black Sea anchovy – to higher one. From the standpoint of the occurred changes in the length-age structure, the current state of anchovy population can be considered as quite good. However, taking into account the sharp decline of relative number of young-of-the-year individuals (0+) in 2016 and 2017, significant rejuvenescence of the population, and consequently anchovy length decrease should be expected in the nearest future.

The condition of the number of universities that very much as well as the changing demands of consumers and potential consumers of the attributes and performance of educational services that they get trigger increased intensity of competition among service providers colleges. Evident of instability number ratio of new admissions process at UMB. This study aims to examine and analyze the effect of brand image, service quality to customer satisfaction as well as its implications on word of mouth at the University of Mercu Buanan Jakarta. The research data is taken from the questionnaire data of 100 students, the results of the calculation formula of slovin with error or error rate of 10% = 0. The sampling method that has been used is convenience sampling of 6947 the population of regular students at UMB. The analysis method that has been used in this research is the Structural Equation Modeling (SEM). Research shows that brand image, service quality and customer satisfaction significantly influence word of mouth. Partially showed that the brand image factors certainly has a positive and significant impact on customer satisfaction, service quality factors are also has a positive and significant impact on customer satisfaction, and customer satisfication factor also has a positive and significant impact on word of mouth. Service quality is the most powerful variable influence on customer satisfaction in Mercu Buana University.

In this paper, mortar specimens with different w/c ratio were tested under axial compression. The damage progress was monitored by acoustic emission (AE) technique and AE signals were collected. AE characteristics of mortar specimens with different w/c ratio are studied and the damage evolution process is analyzed by AE amplitude, peak frequency and AE N/E ratio (cumulative hits/cumulative energy). Under different w/c ratio, variation trend of the ratio of AE cumulative hits number to total AE cumulative hits number (AE cumulative hits number ratio) in each amplitude and frequency band is generally consistent, what’s more, AE cumulative hits number ratio in each frequency band and amplitude band at different stress level are studied. Distribution variation trend of AE cumulative hits number ratio in each amplitude and frequency band changing with the stress is generally consistent. When AE cumulative hits number ratio significantly increases sharply, it indicates that the mortar specimen will be destroyed. The damage evolution progress of mortar specimens with different w/c ratio under axial compression is analyzed by AE cumulative hits number ratio in each frequency band and amplitude band at different stress level and AE N/E ratio.

A reduced mitochondrial DNA (mtDNA) copy number, the ratio of mitochondrial DNA to genomic DNA (mtDNA:gDNA), has been linked with dysfunctional mitochondria. Exercise can acutely induce mtDNA damage manifested as a reduced copy number. However, the influence of a paired (exercise and temperature) intervention on regional mtDNA (MINor Arc and MAJor Arc) are unknown. Thus, the purpose of this study was to determine the acute effects of exercise in cold (7 °C), room temperature (20 °C), and hot (33 °C) ambient temperatures, on regional mitochondrial copy number (MINcn and MAJcn). Thirty-four participants (24.4 ± 5.1 yrs, 87.1 ± 22.1 kg, 22.3 ± 8.5 %BF, and 3.20 ± 0.59 L·min−1 VO2peak) cycled for 1 h (261.1 ± 22.1 W) in either 7 °C, 20 °C, or 33 °C ambient conditions. Muscle biopsy samples were collected from the vastus lateralis to determine mtDNA regional copy numbers via RT-qPCR. mtDNA is sensitive to the stressors of exercise post-exercise (MIN fold change, −1.50 ± 0.11, MAJ fold change, −1.70 ± 0.12) and 4-h post-exercise (MIN fold change, −0.82 ± 0.13, MAJ fold change, −1.54 ± 0.11). The MAJ Arc seems to be more sensitive to heat, showing a temperature-trend (p = 0.056) for a reduced regional copy number ratio after exercise in the heat (fold change −2.81 ± 0.11, p = 0.019). These results expand upon our current knowledge of the influence of temperature and exercise on the acute remodeling of regional mtDNA.

A lockdown is an appropriate method to suppress the spread of COVID-19 in a region. However, apart from the spread of COVID-19, it also affects various aspects and sectors. Therefore, a lockdown decision for a region must go through a careful planning before being finalized. There are many criteria to be considered in a lockdown decision, among them are the number of positive cases, health facilities and demographic situation in an area. This article will discuss a recommender system model that may assist the lockdown decision in a region by considering several criteria originating from multiple databases. in this model had two kinds of inputs, namely internal and external databases. In this case, Internal database is reproduction number of covid-19 case in West Java. External Database is elderly age number ratiom health facility number ratio, nurse ratio and medical worker ratio (specialists and general practitioners), beds in health facilities and population density. The outputs of this method were decisions whether to implement lockdown or new normal for a region in accordance of predetermined parameters. The results of this model can be used for the government in formulating strategies to reduce the number of spread of Covid-19 in terms of determining which areas should apply lockdown.

To quantify the amount of authorized GM maize or soybean, conversion factor (Cf) values are required for converting the copy number ratio of GM sequence to an endogenous sequence into weight-based GMO amounts. Cf values are available for the several latest real-time PCR instruments such as QuantStudio5, QuantStudio12K Flex, LightCycler 96, and LightCycler 480 for GM soybeans but not for GM maize. For the quantification of GM maize, we experimentally determined the Cf values targeting Cauliflower mosaic virus 35S promoter (P35S), GA21 construct specific, MIR604 event specific and MIR162 event specific sequences using the four real-time PCR instruments.

The properties of the young pulsars and their relations to the supernova remnants (SNRs) have been the interesting topics. At present, 383 SNRs in the Milky Way galaxy have been published, which are associated with 64 radio pulsars and 46 pulsars with high energy emissions. However, we noticed that 630 young radio pulsars with spin periods of less than half a second have been not yet observed the SNRs surrounding or nearby them, which arises a question of that could the two types of young radio pulsars with/without SNRs hold distinctive characteristics? Here, we employ the statistical tests on the two groups of young radio pulsars with (52) and without (630) SNRs to reveal if they share different origins. Kolmogorov-Smirnov (K-S) and Mann-Whitney-Wilcoxon (M-W-W) tests indicate that the two samples have the different distributions with parameters of spin period ($P$), derivative of spin period ($\dot P$), surface magnetic field strength ($B$), and energy loss rate ($\dot E$). Meanwhile, the cumulative number ratio between the pulsars with and without SNRs at the different spindown ages decreases significantly after $\rm10-20\,Kyr$. So we propose that the existence of the two types of supernovae (SNe), corresponding to their SNR lifetimes, which can be roughly ascribed to the low-energy and high-energy SNe. Furthermore, the low-energy SNe may be formed from the $\rm8-12\,M_{\odot}$ progenitor, e.g., possibly experiencing the electron capture, while the main sequence stars of $\rm12-25\,M_{\odot}$ may produce the high-energy SNe probably by the iron core collapse., Comment: 8 pages, 10 figures, 3 tables. Published in MNRAS

Aluminium (Al) toxicity inhibits soybean root growth, leading to insufficient water and nutrient uptake. Two soybean lines (‘Magellan’ and PI 567731) were identified differing in Al tolerance, as determined by primary root length ratio, total root length ratio, and root tip number ratio under Al stress. Serious root necrosis was observed in PI 567731, but not in Magellan under Al stress. An F8 recombinant inbred line population derived from a cross between Magellan and PI 567731 was used to map the quantitative trait loci (QTL) for Al tolerance. Three QTL on chromosomes 3, 13, and 20, with tolerant alleles from Magellan, were identified. qAl_Gm13 and qAl_Gm20 explained large phenotypic variations (13–27%) and helped maintain root elongation and initiation under Al stress. In addition, qAl_Gm13 and qAl_Gm20 were confirmed in near-isogenic backgrounds and were identified to epistatically regulate Al tolerance via internal detoxification instead of Al3+ exclusion. Phylogenetic and pedigree analysis identified the tolerant alleles of both loci derived from the US ancestral line, A.K.[FC30761], originally from China. Our results provide novel genetic resources for breeding Al-tolerant soybean and suggest that internal detoxification contributes to soybean tolerance to excessive soil Al.

Ultra-long-chain fatty acids (ULCFAs) are biosynthesized in the restricted tissues such as retina, testis, and skin. The conformation of a single ULCFA, in which the sn-1 unsaturated chain has 32 carbons, in three types of tensionless phospholipid bilayers is studied by molecular dynamics simulations. It is found that the ultra-long tail of the ULCFA flips between two leaflets and fluctuates among an elongation into the opposite leaflet, lying between two leaflets, and turning back. As the number ratio of lipids in the opposite leaflet increases, the ratio of the elongated shape linearly decreases in all three cases. Thus, ULCFAs can sense the density differences between the two leaflets and respond to these changes.

For the last two decades we have been observing a huge increase in discoveries of long-period comets (LPCs), especially those with large-perihelion distances. We collected data for a full sample of LPCs discovered over the 1801-2017 period including their osculating orbits, discovery moments (to study the discovery distances), and original semimajor axes (to study the number ratio of large-perihelion to small-perihelion LPCs in function of 1/a-original, and to construct the precise distribution of an 1/a-original). To minimize the influence of parabolic comets on these distributions we determined definitive orbits (which include eccentricities) for more than 20 LPCs previously classified as parabolic comets. We show that the percentage of large-perihelion comets is significantly higher within Oort spike comets than in a group of LPCs with a

The enforcement of GMO labeling regulations requires validated analytical methods and certified reference materials (CRMs). The early labeling regulations stipulated that the GMO content should be expressed as percentage, but did not specify what unit this percentage referred to. Two reference systems, using mass fraction and copy number ratio as measurement units, individually, are established for GMO analysis using different metrological traceability chains. Three types of CRMs, powder CRMs certified for mass fractions, genomic DNA CRMs, and plasmid DNA CRMs certified for copy number ratios, were developed for calibration and quality control. The type, certification, and measurement unit commutability of current GMO CRMs are presented and discussed in this paper. Both existing reference systems are facing a metrological challenge, although later EU regulations specified that the measurement unit of GMO content must be expressed in mass fraction and recommended to convert one unit into another by introducing a conversion factor, further efforts are required to explore which reference system is more metrologically sound. The determination of conversion factor per CRM batch is recommended to be based on the pure CRMs produced from pure GM materials, which is expected to be the best choice for calibration of PCR measurement results.

We create weakly bound bosonic ${}^{23}{\mathrm{Na}}^{39}\mathrm{K}$ molecules in a mixture of ultracold $^{23}\mathrm{Na}$ and $^{39}\mathrm{K}$. The creation is done in the vicinity of a so far undetected Feshbach resonance at about 196 G which we identify in this work by atom-loss spectroscopy. We investigate the involved molecular state by performing destructive radio-frequency binding-energy measurements. For the constructive molecule creation we use radio-frequency pulses with which we assemble up to 6000 molecules. We analyze the molecule creation efficiency as a function of the radio-frequency pulse duration and the atom number ratio between $^{23}\mathrm{Na}$ and $^{39}\mathrm{K}$. We find an overall optimal efficiency of $6\phantom{\rule{0.16em}{0ex}}%$ referring to the $^{39}\mathrm{K}$ atom number. The measured lifetime of the molecules in the bath of trapped atoms is about 0.3 ms.

ionIn this article, we have designed a sensitive and recycled DNB (DNA nanoball) nanoarrays sequencing complex structures based on BGISEQ-500RS sequencer for the monitoring performance of Exo III activity. In the shortage of Exo III, the effective number ratio of DNB would be captured by an optical system due to one fluorescent. In contrast, in the presence of Exo III, some DNB would disappear or discard from the fields of the optical system by fluorescence extinction and uncleaned fluorescent, respectively. As a result, the effective number of DNB of this strategy was relative to the concentration of Exo III. For Exo III, our strategy showed a highly sensitive linear response in the low detection range of 0.01 U/mL to 0.5 U/mL, with detection limits below 0.01 U/mL. With the comparison between DNB nanoarrays and other fluorescent sensors, this study possessed superior sensitivity, selectivity, and reusability, accompanying with the low cost and simple setup.

Nearby star-forming galaxies offer a unique environment to study the populations of young (<100 Myr) accreting binaries. These systems are tracers of past populations of massive stars that heavily affect their immediate environment and parent galaxies. Using a Chandra X-ray Visionary program, we investigate the young neutron-star binary population in the low metallicity of the Small Magellanic Cloud (SMC) by reaching quiescent X-ray luminosity levels (~few times 1032 erg/s). We present the first measurement of the formation efficiency of high-mass X-ray binaries (HMXBs) as a function of the age of their parent stellar populations by using 3 indicators: the number ratio of HMXBs to OB stars, to the SFR, and to the stellar mass produced during the specific star-formation burst they are associated with. In all cases, we find that the HMXB formation efficiency increases as a function of time up to ~40–60 Myr, and then gradually decreases.

Geochemical and medical ecology studies were conducted in the areas of natural geochemical anomalies with excessive content of heavy metals (Ni, Cr, Co, Cu, Pb) in the Sverdlovsk region (the Middle Urals). The purpose of the work was to study the human morbidity rate in the natural geochemical anomalies (biogeochemical province), which, along with abnormally high content of heavy metals in the soil did not cause endemic diseases. Morbidity data were analyzed by generalized linear model device. The interpretable variable is arcsine-converted value of the cases number ratio to the study area population size. In the course of morbidity average data analysis covering five-year period it's statistically significant increase was stated on the territory of the natural geochemical anomaly (p < 0.001) in comparison with full tone. The main contribution to the morbidity rate increase in the geochemical anomaly make infectious and parasitic diseases, diseases of the circulatory system, respiratory, digestive. As s reason for the increase of morbidity rate is proposed the weakening of immunity under the influence of high concentrations of the chemical elements. Fixed non-specific effect of the natural geochemical factor is probably universal for abnormal areas of the earth's surface, characterized by the endemia absence.

Numerical simulations were carried out to study the origin of multiple stellar populations in the intermediate-age clusters NGC 411 and NGC 1806 in the Magellanic Clouds. We performed NBODY6++ simulations based on two different formation scenarios, an ad hoc formation model where second-generation (SG) stars are formed inside a cluster of first-generation (FG) stars using the gas accumulated from the external intergalactic medium and a minor merger model of unequal mass ($M_{SG}$/$M_{FG}$ ~5-10%) clusters with an age difference of a few hundred million years. We compared our results such as the radial profile of the SG-to-FG number ratio with observations on the assumption that the SG stars in the observations are composed of cluster members, and confirmed that both the ad hoc formation and merger scenarios reproduce the observed radial trend of the SG-to-FG number ratio which shows less centrally concentrated SG than FG stars. It is difficult to constrain the formation scenario for the multiple populations by only using the spatial distribution of the SG stars. SG stars originating from the merger scenario show a significant velocity anisotropy and rotational features compared to those from the ad hoc formation scenario. Thus, observations aimed at kinematic properties like velocity anisotropy or rotational velocities for SG stars should be obtained to better understand the formation of the multiple populations in these clusters. This is, however, beyond current instrumentation capabilities., 11 pages, 8 figures, 1 table; accepted for publication in MNRAS

The Puri-Li kinetic model is explored here to study the contribution of microglia and astroglia during the pathogenesis of Alzheimer's disease (AD). This is carried out by solving the Puri-Li model under steady-state conditions. The derived expressions show that both of them play a role in the pathogenesis of AD. Examination of the steady-state solutions where microglia and astroglia are involved shows that equilibrium conditions are achieved by microglia and astroglia destroying neurons. These findings from this model are in agreement with the results in the literature, where microglia and astroglia are considered to act as inflammatory cells producing toxins to destroy neurons. In addition, the study also showed that the number ratio of the total astroglial cells to the total microglial cells increases with the progression of AD. With advances in three dimensional imaging and selective staining, this ratio could be used as a valuable marker to monitor AD.

Environmental transmission electron microscopy analysis is performed on gold nanoparticulate catalysts with different supports and activities (Au/CeO2, Au/SiO2 and Au/TiC) in pure O2 and CO/air. Examining the morphology of individual Au nanoparticles (AuNPs) numerically followed by statistical treatments, it is suggested that the number ratio of morphology-changeable AuNPs in gases correlated with the catalytic activity. Even in a less active sample of Au/SiO2, the fraction of morphology-changeable AuNPs is not negligible. With the results, we discuss the correlation of catalytic activity with the supports. The present research stimulates further studies on the formation process of perimeter interfaces of individual AuNPs.

The goal of this paper is to characterise the light variation properties of Mira variables in the Small Magellanic Cloud. We have investigated a combined optical and near infrared multi-epoch dataset of Mira variables based on our monitoring data obtained over 15 years. Bolometric correction relations are formulated for various near-infrared colours. We find that the same bolometric correction equation holds for both the bolometricly brightest and faintest pulsation phases. Period-bolometric magnitude relations and period-colour relations were derived using time-averaged values. Phase lags between bolometric phase and optical and near-infrared phases were detected from the O-rich (the surface C/O number ratio is below unity) Mira variables, while no significant systematic lags were observed in most of the C-rich (the C/O ratio is over unity) ones. Some Miras show colour phase inversions, e.g., $H-K_{\rm s}$ at its bluest while $J-H$ and $J-K_{\rm s}$ are at their reddest values at about the bolometricly brightest phase. Their occurrence conditions were studied but no clear direct or indirect trigger was found. A large NIR colour change unassociated with stellar pulsation was observed in Miras with long secondary periods, and its possible explanation is described., Comment: 20 pages, 22 figures, accepted for publication in MNRAS

To reveal the impact mechanism of water droplet diameter distribution in the rain zone on the cooling capacity and water-splashing noise for natural draft wet cooling towers (NDWCTs), a 3 D numerical model of thermal performance and a theoretical calculation model of water-splashing noise were established and validated, respectively. Using these two models, the influences of different diameter distributions on the ventilation, thermal performance, and the sound pressure level (SPL) of water-splashing noise were analyzed to an NDWCT used for 1000 MW unit. The diameter distribution is described by the number ratios, which is the ratio of the number of water droplets with the same diameter to the total number of all the water droplets in the rain zone. The results revealed that, as the number ratio of the water droplet with a diameter of 1 mm or 2 mm increases, the SPL decreases and the cooling capacity worsens. Conversely, when the number ratio of the water droplet with the diameter of 4 mm increases, the SPL also increases, and the cooling capacity is enhanced. In addition, an increase in the number ratio of the water droplet with a diameter of 3 mm acts to improve the ventilation and thermal performance, while the SPL demonstrates a slight reduction. Therefore, when considering the simultaneous optimization of cooling capacity and water-splashing noise, it is recommended that the number ratio of the water droplet with a diameter of 3 mm is increased. When the number ratio of the water droplet with the diameter of 3 mm reaches 45%, compared with the working condition of the actual measured water droplet diameter distribution, the outlet water temperature reduces by 0.22 °C, the ventilation rate increases by 4.72%, while there is no significant change in the SPL.

Authentication of the explosives in nuclear warheads is a key point for the global nuclear disarmament. In this paper, a detection method of the explosives in nuclear warheads based on API-TOF (associated α particle imaging - time of flight) is proposed. First, the basic principles and current research situation of API-TOF are introduced. Second, a numerical simulation platform of the detection method of the explosives in nuclear warheads based on API-TOF was established, and a numerical simulation study of the feasibility of this method was carried out. The research results show that, this method can detect the nuclides of 12C, 14N and 16O of the explosive in the nuclear warhead in 15 min, and reconstruct the carbon-oxygen number ratio and nitrogen-oxygen number ratio of the explosive accurately, and reconstruct the spatial distribution of the explosive nuclei with the explosive profile clearly discriminated in the reconstruction image. From the simulation results, the detection method of the explosive in the nuclear warhead based on API-TOF is confirmed.

Flux-rope/TCR events near the magnetotail lunar orbit ( - 67 R E X * - 39 R E) were studied using magnetic-field and plasma data measured by THEMIS B and C between January 2011 and March 2012. The aberrant coordinate GSM*, where the X * axis is rotated 4° relative to GSM- X , was used to count the occurrence rate. The number ratio of earthward to tailward events was about 3:5. Moreover, the event occurrence rate distribution showed a clear dawn-dusk asymmetry distribution, with dusk-side events accounting for 57.98%. A superposed epoch analysis of the flux-rope events showed that earthward events had a shorter duration in the leading than in the trailing part. Earthward events also displayed a lower temperature and a lower flow speed than tailward events. We studied the relationship between the event occurrence rate and geomagnetic activity level even further. The occurrence rate of tailward flux-rope/TCR events increases with increasing AE-index, whereas earthward events occur mainly in the relatively quiet period of geomagnetic activity (AE ~ 100–300 nT). Flux-rope/TCR events identified within a 10 mm time frame were treated as belonging to a single reconnection event. By comparing the occurrence rates of earthward and tailward events along X *, we estimated the most likely location of the near-Earth reconnection site as X * = - 36 R E.

Mimicking the diverse glyco-conjugate structures in nature is always the dream of scientists. Right now, hierarchical self-assembled structures of natural conjugates of peptides and sugars could not easily be achieved via linear glycopolypeptide with monosaccharides as attachments. In this work, by using a series of well-designed alternating amphiphilic glycopolypeptide brushes (AAGBs) with pendants of glycodendrons and short peptides, various self-assembled morphologies were achieved, including nanowires, nanoribbon, and compound micelles mainly depending on the number ratio of the sugar units to the amino acids species (S/F). Among these morphologies, nanowire attracted our great attention. TEM studies demonstrated that it is formed via a hierarchical self-assembly, i.e., a series of successive processes, including micellization, micelles alignment forming nanofilament, branching of the nanofilaments by micelles, and finally nanowire formation. As far as we know, such hierarchical self-assembly process with high complexity has not been observed in literature for glycopolypeptides even polypeptides, which will deepen our understanding on self-assembly mechanism of natural glyco-conjugates and expand the library of biomimetic materials.

We construct a sample of 10,680 wall galaxies and 3,064 void galaxies with $M_R \lesssim -20$ by cross referencing a void catalog from literature with Baryon Oscillation Spectroscopic Survey (BOSS) CMASS and WiggleZ galaxies, where the CMASS survey targets redder galaxies and the WiggleZ survey targets bluer galaxies. Comparing the density profiles of the red and blue galaxies as a function of the void radius, we find that the number ratio of red-to-blue galaxies increases with distances from the void centers, suggesting a deficit of luminous and normal red galaxies in voids. We find a mean (g -- r) magnitude color of 1.298 and 1.210 for the wall and void galaxies, respectively, when considering the combined red and blue sample, which is found to be a significant difference. However, when considering the blue and red samples separately, we find no significant color difference. We conclude that the constituents galaxies of each population, rather than intrinsic color difference, is the main driver in the apparent average color difference of galaxies in voids and walls, indicating a deficit of luminous and normal red galaxies in voids. Our analysis suggests that the primary environmental-dependence effect on galaxy evolution for normal and luminous galaxies between void and wall regions is manifested in the number of red galaxies, which depends on the environmental-dependent merger history. Using a semi-analytic simulation model, we can successfully reproduce the apparent color difference between the void and wall galaxies., Comment: 11 pages, 10 figures, accepted to MNRAS

Using first-principles calculations, we studied the geometric and band structures of 20 possible configurations of buckled hydrogenated SnPb alloy (SnxPb8−xH8) films. The configurations are topological insulators (TIs) when x ≥ 1. When x increases from 1 to 7, the band gap increases from 0.087 eV to 0.98 eV. The topological characteristics are suggested by s–pxy band inversion and confirmed by helical edge states, which are time-reversal symmetry protected. According to spin–orbit coupling (SOC) analysis results, we draw the conclusion that the Pb atoms have greater SOC strength than the Sn atoms, so when the number ratio of Pb and Sn atoms is greater than 1/12 the SOC strength is large enough to trigger the band inversion between the s and pxy orbitals, causing the SnPb alloy film to turn into a topological insulator (TI) from a normal band insulator (NI). We give a simple rule for the topological criterion of hydrogenated SnPb alloy films by comparing the ratio of Pb and Sn atoms. This would provide a useful reference for the design of topological devices based on NI–TI hetero-junctions for experiments.

Two new antimony(III) quaternary chalcogenides, Na9Sb(Ge2S6)2 and Na9Sb(Ge2Se6)2, were successfully synthesized in vacuum-sealed silica tubes. They crystallize in different space groups: C2/m for Na9Sb(Ge2S6)2 and C2/c for Na9Sb(Ge2Se6)2. In comparison with their structures, similar ethane-like [Ge2Q6]6− ligands and infinite [(Na/Sb)Q4]n chains exist in both of them, but note that two interesting [Na2Sb2(Ge2S6)2]8− and [NaS6] layers are discovered in the structure of Na9Sb(Ge2S6)2, rather than a 3D framework structure for Na9Sb(Ge2Se6)2. Moreover, overall investigation of the quaternary chalcogenides containing M–M bonds (M = Si, Ge) indicates that the orientation of the M–M bonds has a close relation with the number ratio of sodium/another cation and cation radius in the crystal structure, which may provide a feasible way to predict the orientations of the M–M bonds in the layers for new compounds. The UV-vis-NIR diffuse reflectance and IR spectra of Na9Sb(Ge2S6)2 are measured and show that it can be expected to be a promising IR optical window material with a wide IR transmission range from 0.48–22 μm. Raman spectra further verify the IR absorption edges and the presence of Ge–Ge bonds for the title compounds.

Particle detachment from an obliquely oscillating plate was studied experimentally and theoretically. The plate was placed in a horizontal position, and vibrations were applied in the horizontal and vertical directions by piezoelectric vibrators. The frequency of vibration was constant at 280 Hz. The amplitude of vibration increased with time and approached a constant value in each experiment. The movement of micrometer-sized spherical particles was analyzed using images captured by a high-speed microscope camera, which showed that the particles rolled on the plate before detaching from the surface, and that the rolling significantly reduced the adhesive force between the particles and surface. Furthermore, the removal efficiency, defined by the number ratio of detached particles to total particles, was analyzed as a function of the horizontal and vertical vibration accelerations. It was found that the removal efficiency was significantly affected by the horizontal vibration acceleration. These experimental results can be explained by the force and moment balance model.

Digital PCR (dPCR), as a new technology in the field of genetically modified (GM) organism (GMO) testing, enables determination of absolute target copy numbers. The purpose of our study was to test the transferability of methods designed for quantitative PCR (qPCR) to dPCR and to carry out an inter-laboratory comparison of the performance of two different dPCR platforms when determining the absolute GM copy numbers and GM copy number ratio in reference materials certified for GM content in mass fraction. Overall results in terms of measured GM% were within acceptable variation limits for both tested dPCR systems. However, the determined absolute copy numbers for individual genes or events showed higher variability between laboratories in one third of the cases, most possibly due to variability in the technical work, droplet size variability, and analysis of the raw data. GMO quantification with dPCR and qPCR was comparable. As methods originally designed for qPCR performed well in dPCR systems, already validated qPCR assays can most generally be used for dPCR technology with the purpose of GMO detection. Graphical abstract The output of three different PCR-based platforms was assessed in an inter-laboratory comparison.

Objectives The aim of this study was to assess whether the low- to high-kVp computed tomography (CT) number ratio at dual-energy CT is affected by changes in patient diameter. Methods Seven contrast-producing elements were housed sequentially within an abdomen phantom. Fat rings enlarged the phantom diameter from 26 to 44 cm. The phantom was scanned using single-energy CT at tube potentials of 80 and 140 kVp and rapid-kVp-switching dual-energy CT. Results CT numbers decreased proportionally (∼20% CT number reduction for smallest to largest phantom diameters) for low- and high-energy acquisitions but resulted in consistent dual-energy ratios for each contrast element. For 17 of 21 material pair combinations, the dual-energy ratio ranges of the two elements did not overlap, implying that discrimination should remain possible for these material pairs at all patient sizes. Conclusions The dual-energy ratio for different contrast materials is largely unaffected by changes in phantom diameter. This should allow for robust separation of most contrast material combinations irrespective of patient size.

Self-assembly behavior of the blends of AB diblock copolymers and C homopolymers in soft confinement is studied by using a simulated annealing method. Polymer solution droplets in a poor solvent environment realize the soft confinement. Several sequences of soft confinement-induced copolymer aggregates with different shapes and internal structures are predicted as functions of the size of confinement, the number ratio of AB diblock copolymers to C homopolymers, the volume fraction of blocks, the selectivity of confinement’s surface, the incompatibility between blocks, and the competition between two block–homopolymer interactions. Simulation results demonstrate that those factors are able to tune the morphology of the aggregates precisely. We anticipate the rules achieved here is helpful to fabrication of polymeric particle with predesigned morphology.

Background Targeted next-generation sequencing (NGS) has been widely used as a cost-effective way to identify the genetic basis of human disorders. Copy number variations (CNVs) contribute significantly to human genomic variability, some of which can lead to disease. However, effective detection of CNVs from targeted capture sequencing data remains challenging. Results Here we present SeqCNV, a novel CNV calling method designed to use capture NGS data. SeqCNV extracts the read depth information and utilizes the maximum penalized likelihood estimation (MPLE) model to identify the copy number ratio and CNV boundary. We applied SeqCNV to both bacterial artificial clone (BAC) and human patient NGS data to identify CNVs. These CNVs were validated by array comparative genomic hybridization (aCGH). Conclusions SeqCNV is able to robustly identify CNVs of different size using capture NGS data. Compared with other CNV-calling methods, SeqCNV shows a significant improvement in both sensitivity and specificity. Electronic supplementary material The online version of this article (doi:10.1186/s12859-017-1566-3) contains supplementary material, which is available to authorized users.

Aiming at the group of autonomous agents consisting of multiple leader agents and multiple follower ones, a flocking behavior method with multiple leaders and a global trajectory was proposed. In this flocking method, the group leaders can attain the information of the global trajectory, while each follower can communicate with its neighbors and corresponding leader but does not have global knowledge. Being to a distributed control method, the proposed method firstly sets a movable imaginary point on the global trajectory to ensure that the center and average velocity of the leader agents satisfy the constraints of the global trajectory. Secondly, a two-stage strategy was proposed to make the whole group satisfy the constraints of the global trajectory. Moreover, the distance between the center of the group and the desired trajectory was analyzed in detail according to the number ratio of the followers to the leaders. In this way, on one hand, the agents of the group emerge a basic flocking behavior; on the other hand, the center of the group satisfies the constraints of global trajectory. Simulation results demonstrate the effectiveness of the proposed method.

Introduction/Background Recovery from aphasia remains difficult to predict. Among the language features predicting recovery from aphasia, production scores such as repetition or phonology seem to be more relevant predictors than only severity. As motor cortex is strongly involved in language processes, both production and perception, the present study aimed to determine whether the integration of an electrophysiological measure of the motor networks using motor-evoked potentials MEP in the acute phase of stroke can improve the prediction of recovery from post-stroke aphasia. Material and method Hundred and twelve patients with aphasia within 14 days after a first ischemic or haemorrhagic stroke completed the study. The severity of aphasia was assessed using the Aphasia Severity Rating Scale (ASRS) at baseline and 6 month (M6) after the stroke. The ASRS is a 6-point Likert scale from the lowest score 0 to 5. A severe aphasia initially was defined as an ASRS score MEPs were recorded from the abductor pollicis brevis muscle and orbicularis oris. The resting motor threshold (rMT) was defined for each muscle and a ratio between left and right rMT (rMTr) was calculated for upper-limbs and for lips. Results A first-level model, including only clinical variables (i.e. initial severity) predicted severity at six months for severe patients. When the rMTr of upper limbs was added in a second-level model, the predictive power significantly increased from 41 to 51%, as well as adding in a third-level model rMTr of upper-limbs and initial fibres number ratio of the corticospinal tracts (41 to 55%). With the changes of severity as the dependent variable, the same factors made a significant contribution and the predictive power of a second-level model increased from 4 to 20% to the same extent as in a third-level model (4% to 27%). Conclusion Added with usual clinical factors, MEPs of upper-limbs and lips contribute to the prediction of aphasia recovery, particularly for patients with severe aphasia initially.

A field test study was conducted on a natural draft wet cooling tower to quantitatively investigate the water droplet diameter distribution in the rain zone for the first time. A test rig with alterable test positions was designed and constructed. The test time for each set of data is 300 s. The test data are presented in the form of a number ratio (R) with water droplet diameter (d). The results manifest that d is scattered between 0.312 mm and 15 mm, regardless of the crosswind velocity. Under low crosswind speed conditions, R has nearly an identical distribution pattern along the circumferential and radial directions, which are relatively large at d = 0.812 mm and 5.5 mm, respectively. As the droplets move from the position of c1r1h1 to c1r1h3, the R at d > 3.75 mm increases significantly, and the difference in R at d = 0.812 mm and d = 5.5 mm increases from 0.7% to 4.1%, respectively. When the crosswind speed is relatively high, the R is basically consistent at different height positions and shows a difference on the windward side, leading to a noticeable increase in R at d

We present an assembly of cationic and anionic microgels at the air/water interface. Monodispersed, micrometer-sized, and oppositely charged microgels were synthesized by aqueous free-radical precipitation polymerization by using N-isopropylmethacrylamide, comonomers, and cross-linkers. The oppositely charged microgels were prepared by using different types of water-soluble initiators. These microgels were mixed in a solution to assemble them at the air/water interface. In particular, linear and branched chainlike structures of the microgels were spontaneously formed at the air/water interface. Effects of salt concentration, microgel concentration, and number ratio of cationic and anionic microgels on the structures of microgel assembly were investigated by optical microscopy and scanning electron microscopy.

We study fingering instabilities and pattern formation at the interface of an oppositely polarized two-component Bose-Einstein condensate with strong dipole-dipole interactions in three dimensions. It is shown that the rotational symmetry is spontaneously broken by fingering instability when the dipole-dipole interactions are strengthened. Frog-shaped and mushroom-shaped patterns emerge during the dynamics due to the dipolar interactions. We also demonstrate the spontaneous density modulation and domain growth of a two-component dipolar BEC in the dynamics. Bogoliubov analyses in the two-dimensional approximation are performed, and the characteristic lengths of the domains are estimated analytically. Patterns resembling those in magnetic classical fluids are modulated when the number ratio of atoms, the trap ratio of the external potential, or tilted polarization with respect to the z direction is varied., Comment: 9 pages, 10 figures and 4 movies