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Sparse data exist on the complex natural immunity to SARS-CoV-2 at the population level. We applied a well-validated multiplex serology test in 5000 participants of a general population study in Catalonia in blood samples collected from end June to mid November 2020. Based on responses to fifteen isotype-antigen combinations, we detected a seroprevalence of 18.1% in adults (n = 4740), and modeled extrapolation to the general population of Catalonia indicated a 15.3% seroprevalence. Antibodies persisted up to 9 months after infection. Immune profiling of infected individuals revealed that with increasing severity of infection (asymptomatic, 1–3 symptoms, ≥ 4 symptoms, admitted to hospital/ICU), seroresponses were more robust and rich with a shift towards IgG over IgA and anti-spike over anti-nucleocapsid responses. Among seropositive participants, lower antibody levels were observed for those ≥ 60 years vs < 60 years old and smokers vs non-smokers. Overweight/obese participants vs normal weight had higher antibody levels. Adolescents (13–15 years old) (n = 260) showed a seroprevalence of 11.5%, were less likely to be tested seropositive compared to their parents and had dominant anti-spike rather than anti-nucleocapsid IgG responses. Our study provides an unbiased estimate of SARS-CoV-2 seroprevalence in Catalonia and new evidence on the durability and heterogeneity of post-infection immunity. [ABSTRACT FROM AUTHOR]

Serological diagnostic of the severe respiratory distress syndrome coronavirus 2 (SARS-CoV-2) is a valuable tool for the determination of immunity and surveillance of exposure to the virus. In the context of an ongoing pandemic, it is essential to externally validate widely used tests to assure correct diagnostics and epidemiological estimations. We evaluated the performance of the COVID-19 ELISA IgG and the COVID-19 ELISA IgM/A (Vircell, S.L.) against a highly specific and sensitive in-house Luminex immunoassay in a set of samples from pregnant women and cord blood. The agreement between both assays was moderate to high for IgG but low for IgM/A. Considering seropositivity by either IgG and/or IgM/A, the technical performance of the ELISA was highly imbalanced, with 96% sensitivity at the expense of 22% specificity. As for the clinical performance, the negative predictive value reached 87% while the positive predictive value was 51%. Our results stress the need for highly specific and sensitive assays and external validation of diagnostic tests with different sets of samples to avoid the clinical, epidemiological and personal disturbances derived from serological misdiagnosis. [ABSTRACT FROM AUTHOR]

We propose a new history-friendly approach to evolutionary socio-economic dynamics based around competition between five 'utopias' as central ideas about which to order society: capitalism, socialism, civil liberty, nature, and nationalism. In our model, citizens contribute economic resources to support their preferred utopia, and societal dynamics are explained as a co-evolutionary process between these competing utopias. We apply the model to analyze certain aspects of socio-economic and political change in the US from the 1960s-present. We carry out a history-friendly analysis inspired by such episodes as the outbreak of civil movements in the 1970s, the rise of neo-liberalism in the 1980s, and the channels through which America has engendered an 'age of fracture'. Further applications for empirical and theoretical research are suggested. [ABSTRACT FROM AUTHOR]

In this paper, we propose an industrial dynamics model to analyze the interactions between the price-performance sensitivity of demand, the sources of innovation in a sector, and certain features of the corresponding pattern of industrial transformation. More precisely, we study market concentration in different technological regimes and demand conditions. The computational analysis of our model shows that market demand plays a key role in industrial dynamics. Thus, although for intermediate values of the price-performance sensitivity, our results show the well-known relationships in the literature between technological regimes and industry transformation, we find surprising outcomes when demand is strongly biased either towards price or performance. Hence, for different technological regimes, a high performance sensitivity of demand tends to concentrate the market. On the other hand, under conditions of high price sensitivity, the industry generally tends to atomize. That is to say, for extreme values of the price-performance sensitivity of demand, we find concentrated or atomized market structures no matter the technological regime we are in. These results highlight the importance of considering the role of demand in the analysis of industrial dynamics. [ABSTRACT FROM AUTHOR]

This paper illustrates how a deterministic approximation of a stochastic process can be usefully applied to analyse the dynamics of many simple simulation models. To demonstrate the type of results that can be obtained using this approximation, we present two illustrative examples which are meant to serve as methodological references for researchers exploring this area. Finally, we prove some convergence results for simulations of a family of evolutionary games, namely, intra-population imitation models in n-player games with arbitrary payoffs. [ABSTRACT FROM AUTHOR]

The Lunar Orbiter Laser Altimeter (LOLA) is an instrument on the payload of NASA’s Lunar Reconnaissance Orbiter spacecraft (LRO) (Chin et al., in Space Sci. Rev. 129:391–419, ). The instrument is designed to measure the shape of the Moon by measuring precisely the range from the spacecraft to the lunar surface, and incorporating precision orbit determination of LRO, referencing surface ranges to the Moon’s center of mass. LOLA has 5 beams and operates at 28 Hz, with a nominal accuracy of 10 cm. Its primary objective is to produce a global geodetic grid for the Moon to which all other observations can be precisely referenced. [ABSTRACT FROM AUTHOR]

The objective of the Lunar Reconnaissance Orbiter (LRO) Laser Ranging (LR) system is to collect precise measurements of range that allow the spacecraft to achieve its requirement for precision orbit determination. The LR will make one-way range measurements via laser pulse time-of-flight from Earth to LRO, and will determine the position of the spacecraft at a sub-meter level with respect to ground stations on Earth and the center of mass of the Moon. Ranging will occur whenever LRO is visible in the line of sight from participating Earth ground tracking stations. The LR consists of two primary components, a flight system and ground system. The flight system consists of a small receiver telescope mounted on the LRO high-gain antenna that captures the uplinked laser signal, and a fiber optic cable that routes the signal to the Lunar Orbiter Laser Altimeter (LOLA) instrument on LRO. The LOLA instrument receiver records the time of the laser signal based on an ultrastable crystal oscillator, and provides the information to the onboard LRO data system for storage and/or transmittal to the ground through the spacecraft radio frequency link. The LR ground system consists of a network of satellite laser ranging stations, a data reception and distribution facility, and the LOLA Science Operations Center. LR measurements will enable the determination of a three-dimensional geodetic grid for the Moon based on the precise seleno-location of ground spots from LOLA. [ABSTRACT FROM AUTHOR]

Development of SARS-CoV-2 reagents was partially supported by the NIAID Centers of Excellence for Influenza Research and Surveillance (CEIRS) contract HHSN272201400008C. The Funding section now reads: "This study was partially funded by the KidsCorona Child and Mother COVID-19 OpenData and Biobank Initiative from Hospital Sant Joan de Déu (Stavros Niarchos Foundation, Santander Foundation and others), LaCaixa Foundation, Sant Pau Research Institute, ISGlobal and Fundació Privada Daniel Bravo Andreu, Barcelona, Spain. The original article can be found online at https://doi.org/10.1038/s41598-021-98296-y. [Extracted from the article]

The Mercury Laser Altimeter (MLA) is one of the payload science instruments on the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) mission, which launched on August 3, 2004. The altimeter will measure the round-trip time of flight of transmitted laser pulses reflected from the surface of the planet that, in combination with the spacecraft orbit position and pointing data, gives a high-precision measurement of surface topography referenced to Mercury’s center of mass. MLA will sample the planet’s surface to within a 1-m range error when the line-of-sight range to Mercury is less than 1,200 km under spacecraft nadir pointing or the slant range is less than 800 km. The altimeter measurements will be used to determine the planet’s forced physical librations by tracking the motion of large-scale topographic features as a function of time. MLA’s laser pulse energy monitor and the echo pulse energy estimate will provide an active measurement of the surface reflectivity at 1,064 nm. This paper describes the instrument design, prelaunch testing, calibration, and results of postlaunch testing. [ABSTRACT FROM AUTHOR]

Eight samples of peach nectars were profiled by a trained panel and assessed for overall liking by a consumer panel. Internal preference mapping was used to derive a multidimensional space of samples based only on acceptance data. The first three preference dimensions showed significant fit for 91.2% of the consumer population. According to the position of these consumers on the maps, four subgroups could be formed. The first dimension was mainly related to sweetness and off-flavour. The second dimension was related to acidity and texture attributes (body, viscosity, sliminess, mouth-coating) and the third dimension was defined by flavour intensity, peach flavour, and artificial and cooked flavours. Based on these results, the preference criteria of each consumer subgroups were established. [ABSTRACT FROM AUTHOR]

The Repertory Grid method was used to aid consumers in developing a vocabulary to describe the sensory characteristics perceived from samples of three varieties of apples (Cox, Jonagold and Boskoop) from three different harvest dates each (early, middle, and late harvest). The aims of this work were to study whether consumers perceived different degrees of mealiness and to compare the perceptual spaces of samples obtained from consumer data and from conventional profiling with a trained panel, using Generalized Procrustes analysis. The relative positions of samples were similar for the consumers and the trained assessors' consensus spaces but the latter resulted in a better separation of samples. Boskoop samples were perceived as more acid, astringent, crispy and hard while the Cox variety was described as sweeter and more floury. Jonagold samples were perceived as juicier and occupied an intermediate position, with the mealy Jonagold sample closer to the Cox samples. The agreement between sample spaces showed that both panels perceived the major differences between samples in a similar way but the trained panel was able to differentiate further, mainly between the texture characteristics. [ABSTRACT FROM AUTHOR]

In rat pre-implantation embryos, we compared the polarization of cytoplasmic organelles with cell membrane regionalization as revealed by the cytochemical demonstration of 5′-nucleotidase and alkaline phosphatase. The polarization is shown at the eight-cell stage by columns of organelles extending from the nuclei to the embryo periphery. No consistent segregation of cytoplasmic components was recognized prior to the eight-cell stage. As to regionalization, both enzyme activities were demonstrated, from the late four-cell stage onwards on the cell surface between blastomeres of early and late morulae, while the external surface of the embryo lacked these activities. In early blastocysts, these enzyme activities were lost on the inner surface of the blastocyst cavity and in late blastocysts; 5′-nucleotidase activity appeared on the external surface of the embryonal trophoplast and extended to the abembryonal pole. From these observations we conclude that cell membrane regionalization precedes the polarization of the cytoplasm; however, this temporal relationship does not necessarily imply a causal relationship, since both phenomena may be independent expressions of an underlying morphonetic process. [ABSTRACT FROM AUTHOR]

A cytochemical method has been used to test claims that the differentiation of the mouse morulae can be accounted for by the position of the blastomeres: the central becoming inner mass cells and the peripheral trophoblast cells. The cytochemical method is an adaptation of Gomori-Takamatsu's demonstration of alkaline phosphatase activity, which stains the inner cell mass and not the trophoblast. The significance of this procedure is dicussed. A simple physical model shows that by packing spheres of similar size, at least 17 are needed to have one completely enclosed. On these basis, if the position is the decisive factor, alkaline phosphatase activity should be detected in embryos with more than 17 cells. Table 1 shows that it is a correct assumption. But since blastomeres that have gone through more cell cycles are smaller and have a better chance of reaching a central position, it became necessary to dissociate number of cells from number of cell cycles. This we did by detecting the appearance of the enzyme activity in halved and fused embryos developed in vitro. Table 2 shows that the activity is detected in halved embryos from the 11-cell stage onwards. Table 3 shows that it is detected in fusion embryos from the 22-cell stage onwards. The results suggest that a temporal coordinate, the number of cell cycles or another temporal change, might interact with the spatial coordinate to produce differentiation. [ABSTRACT FROM AUTHOR]

Hereditary hydronephrosis (MIM 143400) is an autosomal dominant trait that causes unilateral or bilateral pelvi-ureteric junction (PUJ) obstruction. Linkage analysis was undertaken in 5 families with hereditary PUJ obstruction using the major histocompatibility complex locus as a test marker. The data as a whole supported a hereditary hydronephrosis locus on 6p. Maximal lod scores were 3.090 at a recombination fraction of 0.1 with full penetrance, and 2.486 at a recombination fraction of 0.1 with a penetrance of 90%. However, analysis of two point lod scores using the HOMOG program revealed significant evidence for genetic heterogeneity with one locus on 6p in 4 of the families, and a different locus in one family. After exclusion of this unlinked family, two point analysis gave a maximal lod score of 3.9 at a recombination fraction of 0.05 with full penetrance, and 4.2 at a recombination fraction of 0.0 with 90% penetrance. These data support the assignment of one of the loci for hereditary hydronephrosis to chromosome 6p. [ABSTRACT FROM AUTHOR]

Observations by scanning electron microscopy of mouse cleaving embryos reveal the presence of long microvilli around cell contact regions that often bridge the gap between blastomeres. These microvilli correspond, in detergent-extracted morulae, to strings connecting the cortical cytoskeletons of adjoining cells. They appear about 4 h after compaction in synchronized cultures. Transmission electron microscopy, heavy meromyosin decoration and DNase I digestion show that cytoskeletal connections contain bundles of actin microfilaments. The establishment of cytoskeletal connections does not require immediate protein synthesis, as shown by incubation with cycloheximide. Diverse treatments that interfere with compaction were tested for the development of cytoskeletal connections: culture media with low Ca and/or Mg, or EGTA, or α-lactalbumin, do not prevent the establishment of connections, while colchicine delays their appearance and cytochalasin D suppresses it. The relation between cytoskeletal connections, compaction and blastulation is discussed. [ABSTRACT FROM AUTHOR]

Two-cell mouse ova, which were centrifuged for l h at 70 000-90 000x g, showed a precise stratification of the cytoplasm and an elongation of the nucleus. The ova were fixed at different times and observed by light and electron microscopy using cytochemical methods and detergent extractions. Within 40 min after centrifugation the normal-looking morphology was recovered except for the persisting lipid caps at the centripetal poles of the blastomeres. Cleavage, compaction and blastulation were not prevented by centrifugation. Treatments with colcemid or cytochalasin D delayed but did not impair recovery. These results suggest that a resilient cytoskeletal structure may be involved in this kind of embryonic regulation. [ABSTRACT FROM AUTHOR]

The early development of the rat, from the mature oocyte through fertilization until the 8-cell stage, has been studied with the electron microscope. The fine structure is described and discussed, with particular reference to the following topics. The middle piece of the spermatozoon is found in every stage studied, within the ovum cytoplasm; it is not significantly altered by this situation. The nucleoli are numerous during the 1-cell stage and often present in positions that suggest their extrusion into the cytoplasm; in subsequent stages a branching structure develops around them. The dividing cell presents the mitotic apparatus with its centrioles, hollow looking fibers, chromosomes, but without centromeres; in the cytoplasm the small granules align in rows. Mitochondria are evenly distributed during the 1-cell stage and can be found in the 8-cell stage constricted as if dividing. The 'multivesicular bodies' constitute an abundant population of cytoplasmic elements that may be related to the endoplasmic reticulum or the Golgi complex, neither of which is clearly recognizable. In the 8-cell stage the cytoplasm segregates into two zones, one of which contains all the 'multivesicular bodies', while the mitochondria are found in both of them; this distinction provides some basis to adscribe to the 'multivesicular bodies' the properties of the so called 'metachromatic particles'. [ABSTRACT FROM AUTHOR]

Glycosylation is an important posttranslational protein modification in all eukaryotes. Besides glycosylphosphatidylinositol (GPI) anchors and N-glycosylation, O-fucosylation has been recently reported in key sporozoite proteins of the malaria parasite. Previous analyses showed the presence of GDP-fucose (GDP-Fuc), the precursor for all fucosylation reactions, in the blood stages of Plasmodium falciparum. The GDP-Fuc de novo pathway, which requires the action of GDP-mannose 4,6-dehydratase (GMD) and GDP-L-fucose synthase (FS), is conserved in the parasite genome, but the importance of fucose metabolism for the parasite is unknown. To functionally characterize the pathway we generated a PfGMD mutant and analyzed its phenotype. Although the labelling by the fucose-binding Ulex europaeus agglutinin I (UEA-I) was completely abrogated, GDP-Fuc was still detected in the mutant. This unexpected result suggests the presence of an alternative mechanism for maintaining GDP-Fuc in the parasite. Furthermore, PfGMD null mutant exhibited normal growth and invasion rates, revealing that the GDP-Fuc de novo metabolic pathway is not essential for the development in culture of the malaria parasite during the asexual blood stages. Nonetheless, the function of this metabolic route and the GDP-Fuc pool that is generated during this stage may be important for gametocytogenesis and sporogonic development in the mosquito. [ABSTRACT FROM AUTHOR]