Replenished ethnicity Jimenez, Tomas R; Jimenez, Tomas R
2010., 20091019, 2009, c2010., 2009-11-18, 20100101
eBook
Unlike the wave of immigration that came through Ellis Island and then subsided, immigration to the United States from Mexico has been virtually uninterrupted for one hundred years. In this vividly ...detailed book, Tomás R. Jiménez takes us into the lives of later-generation descendents of Mexican immigrants, asking for the first time how this constant influx of immigrants from their ethnic homeland has shaped their assimilation. His nuanced investigation of this complex and little-studied phenomenon finds that continuous immigration has resulted in a vibrant ethnicity that later-generation Mexican Americans describe as both costly and beneficial. Replenished Ethnicity sheds new light on America's largest ethnic group, making it must reading for anyone interested in how immigration is changing the United States.
The immigration patterns of the last three decades have profoundly changed nearly every aspect of life in the United States. What do those changes mean for the most established Americans-those whose ...families have been in the country for multiple generations?The Other Side of Assimilationshows that assimilation is not a one-way street. Jiménez explains how established Americans undergo their own assimilation in response to profound immigration-driven ethnic, racial, political, economic, and cultural shifts. Drawing on interviews with a race and class spectrum of established Americans in three different Silicon Valley cities,The Other Side of Assimilationilluminates how established Americans make sense of their experiences in immigrant-rich environments, in work, school, public interactions, romantic life, and leisure activities. With lucid prose, Jiménez reveals how immigration not only changes the American cityscape but also reshapes the United States by altering the outlooks and identities of its most established citizens.
Recent research in humans, livestock, and wildlife using high-throughput next-generation sequencing (NGS) has identified that resident microbiota play an essential role in disease resistance, host ...health, and adaptation to biotic and abiotic stressors. Since amphibians are currently facing population declines and extinctions attributable to anthropogenic pressures and emerging diseases, an understanding of the effects of microbiome dysbiosis and mitigation is a prerequisite for amphibian conservation and disease management. Interest is now growing with regard to understanding the influence of unfavorable environmental conditions on the amphibian microbiome and the effects of dysbiosis on the susceptibility to pathogenic infections. Here, we summarize information on the amphibian microbiome, specifically concerning intrinsic and extrinsic factors that shape the skin and gut microbiome. We explore diverse types of unfavorable environmental perturbations and the ways in which they can impact the microbiota of an individual so that we can better comprehend the consequences of stressors and dysbiosis on pathogen emergence and health. We discuss the role of the microbiome in amphibian conservation and identify gaps of knowledge that need to be filled if we are to achieve a meta-organism conservation approach. NGS studies should be complemented with other high-throughput “-omic” approaches to target microbiome functionality. Understanding the microbiome might be the missing piece in the overall strategy that will help maintain the health of amphibians in a world with highly affected environments and that will prevent/mitigate emerging infectious diseases.
In GPS-denied indoor environments, localization and tracking of people can be achieved with a mobile device such as a smartphone by processing the received signal strength (RSS) of RF signals emitted ...from known location beacons (anchor nodes), combined with Pedestrian Dead Reckoning (PDR) estimates of the user motion. An enhacement of this localization technique is feasible if the users themselves carry additional RF emitters (mobile nodes), and the cooperative position estimates of a group of persons incorporate the RSS measurements exchanged between users. We propose a centralized cooperative particle filter (PF) formulation over the joint state of all users that permits to process RSS measurements from both anchor and mobile emitters, as well as PDR motion estimates and map information (if available) to increase the overall positioning accuracy, particularly in regions with low density of anchor nodes. Smartphones are used as a convenient mobile platform for sensor measurements acquisition, low-level processing, and data transmission to a central unit, where cooperative localization processing takes place. The cooperative method is experimentally demonstrated with four users moving in an area of 1600 m 2 , with 7 anchor nodes comprised of active RFID (radio frequency identification) tags, and additional mobile tags carried by each user. Due to the limited coverage provided by the anchor beacons, RSS-based individual localization is inaccurate (6.1 m median error), but this improves to 4.9 m median error with the cooperative PF. Further gains are produced if the PDR information is added to the filter: median error of 3.1 m (individual) and 2.6 m (cooperative); and if map information is also considered, the results are 1.8 m (individual) and 1.6 m (cooperative). Thus, for each version of the particle filter, cooperative localization outperforms individual localization in terms of positioning accuracy.
The location of people, robots, and Internet-of-Things (IoT) devices has become increasingly important. Among the available location technologies, solutions based on ultrawideband (UWB) radio are ...having much success due to their accuracy, which is ideally at a centimeter level. However, this accuracy is degraded in most common indoor environments due to the presence of obstacles which block or reflect the radio signals used for ranging. One way to circumvent this difficulty is through robust estimation algorithms based on measurement redundancy, permitting to minimize the effect of significantly erroneous ranges (outliers). This need for redundancy often conflicts with hardware restraints put up by the location system's designers. In this work, we present a procedure to increase the redundancy of UWB systems and demonstrate it with the help of a commercial system made by Decawave. This system is particularly easy to deploy, by configuring a network of beacons (anchors) and devices (tags) to be located; however, its architecture presents a major disadvantage as each tag to be located can only measure ranges to a maximum of four anchors. This limitation is embedded in the Positioning and Networking Stack (PANS) protocol designed by Decawave, and therefore is not easy to bypass without a total redesign of the firmware. In this paper, we analyze the strategies that we have been able to identify in order to provide this equipment with multiple range measurements, and thus enable each tag to be positioned with more than four measured ranges. We will see the advantages and disadvantages of each of these strategies, and finally we will adopt a solution that we implemented to be able to measure up to eight ranges for each mobile device (tag). This solution implies the duplication of the tags at the mobile user, and the creation of a double interleaved network of anchors. The range among tags and the eight beacons is obtained through an API via a wireless BLE protocol at a 10 Hz rate. A robustified Extended Kalman filter (EKF) is designed to estimate, by trilateration, the position of the pair of mobile tags, using eight ranges. Two different scenarios are used to make localization experimentation: a laboratory and an apartment. Our position estimation, which exploits redundant information and performs outlier removal, is compared with the commercial solution limited to four ranges, demonstrating the need and advantages of our multi-range approach.
Display omitted
•Bioink formulations based on alginate and CNF (cellulose nanofibers) were developed.•Suitable alginate-CNF formulations were successfully 3D printed showing shape ...fidelity.•Freeze-dried scaffolds presented CNF modulated porosity and stiffness.•Curcumin was successfully stabilized in the bioinks, and loaded patches were 3D printed.•Curcumin release kinetics showed dependence on both CNF content and scaffold disintegration.
Alginate and nanocellulose are potential biomaterials to be employed as bioinks for three-dimensional (3D) printing. Alginate-cellulose nanofibers (A-CNF) formulations with CNF amounts up to 5 wt% were developed and rheologically characterized to evaluate their printability. Results showed that formulations with less than 3 wt% CNF did not present suitable characteristics to ensure shape fidelity after printing. Selected A-CNF bioinks were 3D printed and freeze-dried to obtain porous scaffolds. Morphological and mechanical analysis were performed, showing that CNF contributed to the reinforcement of the scaffolds and modulated their porosity. The applicability for drug delivery was evaluated by the addition of curcumin to printable A-CNF formulations. The curcumin loaded bioinks were successfully 3D printed in patches and the in vitro release tests showed that alginate and CNF played an important role in curcumin stabilization, whereas the CNF content and the disintegration of the scaffold were essential in the release kinetics.
We report a new cyanide-bridged Cs⊂{Fe
Co
} box, a soluble model of photomagnetic Prussian blue analogues (PBAs). The Cs
ion has a high affinity for the box and can replace the K
ion in the preformed ...K-cube. This exchange is kinetically impeded at room temperature but is accelerated by heating and using the 18-crown-6 ether. The inserted Cs
ion confers a high robustness to the cube, which withstands boiling, as shown by variable-temperature NMR studies. The stability of this model complex in solution allows the probing of the electronic interaction between the alkali ion and the cyanide cage by using various techniques. These interactions are known to play a role in the photomagnetic behaviour of PBAs. Firstly, the
Cs NMR spectroscopy proves that there is an electronic communication between the encapsulated alkali ion and the cyanide cage. The measured up-field signal, observed at ca. -200 ppm at 300 K, reveals that a certain amount of spin density is transferred through the bonds from the paramagnetic Co(ii) ion to the encapsulated cation. Secondly, cyclovoltammetric studies show that the nature of the inserted ions affects the redox properties of the cage and influences the electronic communication between the metal ions. However, the differences in the electrochemical properties of the K-cube and the Cs-cube remain moderate. As the switching properties are influenced by the redox potential of the Fe and Co centers, similar photomagnetic behaviour is observed, with both of them being highly photomagnetic. This result contrasts strikingly with previous studies on the 3D polymeric PBAs, where the PBAs with a high amount of Cs
show poor photomagnetic behaviour. In that case, cooperative behaviour likely influences the switching properties. Finally, EPR spectroscopy shows that the K-cube is more anisotropic than the Cs-cube. This difference is reflected in the changes occurring in the slow magnetic relaxation (single molecule magnet behaviour) observed in the two cubes.
Group I alkoxides are highly active precatalysts in the heterodehydrocoupling of silanes and amines to afford aminosilane products. The broadly soluble and commercially available KOtAmyl was utilized ...as the benchmark precatalyst for this transformation. Challenging substrates such as anilines were found to readily couple primary, secondary, and tertiary silanes in high conversions (>90 %) after only 2 h at 40 °C. Traditionally challenging silanes such as Ph3SiH were also easily coupled to simple primary and secondary amines under mild conditions, with reactivity that rivals many rare earth and transition‐metal catalysts for this transformation. Preliminary evidence suggests the formation of hypercoordinated intermediates, but radicals were detected under catalytic conditions, indicating a mechanism that is rare for Si−N bond formation.
Group I alkoxides and amylates efficiently catalyze the heterodehydrocoupling of challenging silane and amine substrates under mild conditions! This represents one of the most straightforward and accessible methods to form aminosilanes through heterodehydrocoupling! This train is now leaving the station – don't miss it!
The literature on assimilation and ethnic identity formation largely assumes that the durability of ethnic boundaries is a function of the assimilation measures that sociologists commonly employ. But ...this literature fails to account adequately for the role of immigration patterns in explaining the durability and nature of ethnic boundaries. Using 123 in-depth interviews with later-generation Mexican Americans, this article shows that Mexican immigrant replenishment shapes ethnic boundaries and ethnic identity formation. The sizable immigrant population sharpens intergroup boundaries through the indirect effects of nativism and by contributing to the continuing significance of race in the lives of later-generation Mexican Americans. The presence of a large immigrant population also creates intragroup boundaries that run through the Mexican-origin population and that are animated by expectations about ethnic authenticity. The article illustrates the importance of immigrant replenishment to processes of assimilation and ethnic identity formation.
Background: Nuclear short-range correlations (SRCs) are corrections to mean-field wave functions connected with the short-distance behavior of the nucleon-nucleon interaction. These SRCs provide ...corrections to lepton-nucleus cross sections as computed in the impulse approximation (IA). Purpose: We want to investigate the influence of SRCs on the one-nucleon (1N) and two-nucleon (2N) knockout channels for muon-neutrino induced processes on a 12 C target at energies relevant for contemporary measurements. Method: The model adopted in this work corrects the impulse approximation for SRCs by shifting the complexity induced by the SRCs from the wave functions to the operators. Due to the local character of the SRCs, it is argued that the expansion of these operators can be truncated at a low order. Results: The model is compared with electron-scattering data, and two-particle two-hole responses are presented for neutrino scattering. The contributions from the vector and axial-vector parts of the nuclear current as well as the central, tensor, and spin-isospin parts of the SRCs are studied. Conclusions: Nuclear SRCs affect the 1N knockout channel and give rise to 2N knockout. The exclusive neutrino-induced 2N knockout cross section of SRC pairs is shown and the 2N knockout contribution to the QE signal is calculated. The strength occurs as a broad background which extends into the dip region.
PDF
