BACKGROUND
An alginate-based matrix supports the three-dimensional (3D) architecture of non-human primate follicles and, in the presence of FSH, permits the in vitro development of pre-antral ...follicles to the small antral stage, including the production of ovarian steroids and paracrine factors. The current study investigated the ability of gonadotrophins, fetuin and oxygen (O2) to improve primate follicle growth and oocyte maturation in vitro.
METHODS
Macaque secondary follicles were isolated from the early follicular phase ovaries, encapsulated in a sodium alginate matrix and cultured individually for 40 days in supplemented medium. The effects of recombinant human (rh) FSH (15, 3 and 0.3 ng/ml for high, medium and low FSH, respectively), bovine fetuin (1 or 0 mg/ml) and O2 (5 or 20% v/v) were examined. Half of the follicles in each culture condition received rhLH on Day 30–40. Follicles that reached antral stage were treated with rh chorionic gonadotrophin for 34 h to initiate oocyte meiotic maturation. Media were analyzed for ovarian steroids and anti-müllerian hormone (AMH).
RESULTS
Improved culture conditions supported non-human primate, secondary follicle growth to the antral stage and, for the first time, promoted oocyte maturation to the MII stage. In the presence of fetuin at 5% O2, follicles had the highest survival rate if cultured with high or medium FSH, whereas follicles grew to larger diameters at Week 5 in low FSH. Oocyte health and maturation were promoted under 5% O2. High FSHstimulated steroid production by growing follicles, and steroidogenesis by follicles cultured with low FSH was promoted by LH. AMH biosynthesis was elevated with high compared with low FSH and for longer under 5% O2 than under 20% O2.
CONCLUSIONS
This encapsulated 3D culture model permits further studies on the endocrine and local factors that influence primate follicle growth and oocyte maturation, with relevance to enhancing fertility preservation options in women.
The iron-based high temperature superconductors exhibit a rich phase diagram reflecting a complex interplay between spin, lattice, and orbital degrees of freedom. The nematic state observed in these ...compounds epitomizes this complexity, by entangling a real-space anisotropy in the spin fluctuation spectrum with ferro-orbital order and an orthorhombic lattice distortion. A subtle and less-explored facet of the interplay between these degrees of freedom arises from the sizable spin-orbit coupling present in these systems, which translates anisotropies in real space into anisotropies in spin space. We present nuclear magnetic resonance studies, which reveal that the magnetic fluctuation spectrum in the paramagnetic phase of BaFe2As2 acquires an anisotropic response in spin-space upon application of a tetragonal symmetry-breaking strain field. Our results unveil an internal spin structure of the nematic order parameter, indicating that electronic nematic materials may offer a route to magneto-mechanical control.
In animal communication, functionally referential alarm calls elicit the same behavioral responses as their referents, despite their typically distinct bioacoustic traits. Yet the auditory forebrain ...in at least one songbird species, the black-capped chickadee Poecile atricapillus, responds similarly to threat calls and their referent predatory owl calls, as assessed by immediate early gene responses in the secondary auditory forebrain nuclei. Whether and where in the brain such perceptual and cognitive equivalence is processed remains to be understood in most other avian systems. Here, we studied the functional neurogenomic (non-) equivalence of acoustic threat stimuli perception by the red-winged blackbird Agelaius phoeniceus in response to the actual calls of the obligate brood parasitic brown-headed cowbird Molothrus ater and the referential anti-parasitic alarm calls of the yellow warbler Setophaga petechia, upon which the blackbird is known to eavesdrop. Using RNA-sequencing from neural tissue in the auditory lobule (primary and secondary auditory nuclei combined), in contrast to previous findings, we found significant differences in the gene expression profiles of both an immediate early gene, ZENK (egr-1), and other song-system relevant gene-products in blackbirds responding to cowbird vs. warbler calls. In turn, direct cues of threats (including conspecific intruder calls and nest-predator calls) elicited higher ZENK and other differential gene expression patterns compared to harmless heterospecific calls. These patterns are consistent with a perceptual non-equivalence in the auditory forebrain of adult male red-winged blackbirds in response to referential calls and the calls of their referents.
Blue‐Green Infrastructure (BGI) and Sustainable Drainage Systems (SuDS) are increasingly recognised as vital components of urban flood risk management. However, uncertainty regarding their hydrologic ...performance and lack of confidence concerning their public acceptability create concerns and challenges that limit their widespread adoption. This paper investigates barriers to implementation of BGI in Portland, Oregon, using the Relevant Dominant Uncertainty (RDU) approach. Two types of RDU are identified: scientific RDUs related to physical processes that affect infrastructure performance and service provision, and socio‐political RDUs that reflect a lack of confidence in socio‐political structures and public preferences for BGI. We find that socio‐political RDUs currently exert the strongest negative influences on BGI decision making in Portland. We conclude that identification and management of both biophysical and socio‐political uncertainties are essential to broadening the implementation of BGI and sustainable urban flood risk management solutions that are practical, scientifically sound, and supported by local stakeholders.
Global distributions of thermal, epithermal, and fast neutron fluxes have been mapped during late southern summer/northern winter using the Mars Odyssey Neutron Spectrometer. These fluxes are ...selectively sensitive to the vertical and lateral spatial distributions of H and CO2in the uppermost meter of the martian surface. Poleward of ±60° latitude is terrain rich in hydrogen, probably H2Oice buried beneath tens of centimeter-thick hydrogen-poor soil. The central portion of the north polar cap is covered by a thick CO2layer, as is the residual south polar cap. Portions of the low to middle latitudes indicate subsurface deposits of chemically and/or physically bound H2Oand/or OH.
We report a genome-wide association study (GWAS) of major depressive disorder (MDD) in 1221 cases from the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study and 1636 screened ...controls. No genome-wide evidence for association was detected. We also carried out a meta-analysis of three European-ancestry MDD GWAS data sets: STAR*D, Genetics of Recurrent Early-onset Depression and the publicly available Genetic Association Information Network-MDD data set. These data sets, totaling 3957 cases and 3428 controls, were genotyped using four different platforms (Affymetrix 6.0, 5.0 and 500 K, and Perlegen). For each of 2.4 million HapMap II single-nucleotide polymorphisms (SNPs), using genotyped data where available and imputed data otherwise, single-SNP association tests were carried out in each sample with correction for ancestry-informative principal components. The strongest evidence for association in the meta-analysis was observed for intronic SNPs in ATP6V1B2 (P=6.78 x 10⁻⁷), SP4 (P=7.68 x 10⁻⁷) and GRM7 (P=1.11 x 10⁻⁶). Additional exploratory analyses were carried out for a narrower phenotype (recurrent MDD with onset before age 31, N=2191 cases), and separately for males and females. Several of the best findings were supported primarily by evidence from narrow cases or from either males or females. On the basis of previous biological evidence, we consider GRM7 a strong MDD candidate gene. Larger samples will be required to determine whether any common SNPs are significantly associated with MDD.
Language grounding is broadly defined as the problem of mapping natural language instructions to robot behavior. To truly be effective, these language grounding systems must be accurate in their ...selection of behavior, efficient in the robot’s realization of that selected behavior, and capable of generalizing beyond commands and environment configurations only seen at training time. One choice that is crucial to the success of a language grounding model is the choice of representation used to capture the objective specified by the input command. Prior work has been varied in its use of explicit goal representations, with some approaches lacking a representation altogether, resulting in models that infer whole sequences of robot actions, while other approaches map to carefully constructed logical form representations. While many of the models in either category are reasonably accurate, they fail to offer either efficient execution or any generalization without requiring a large amount of manual specification. In this work, we take a first step towards language grounding models that excel across accuracy, efficiency, and generalization through the construction of simple, semantic goal representations within Markov decision processes. We propose two related semantic goal representations that take advantage of the hierarchical structure of tasks and the compositional nature of language respectively, and present multiple grounding models for each. We validate these ideas empirically with results collected from following text instructions within a simulated mobile-manipulator domain, as well as demonstrations of a physical robot responding to spoken instructions in real time. Our grounding models tie abstraction in language commands to a hierarchical planner for the robot’s execution, enabling a response-time speed-up of several orders of magnitude over baseline planners within sufficiently large domains. Concurrently, our grounding models for generalization infer elements of the semantic representation that are subsequently combined to form a complete goal description, enabling the interpretation of commands involving novel combinations never seen during training. Taken together, our results show that the design of semantic goal representation has powerful implications for the accuracy, efficiency, and generalization capabilities of language grounding models.
Evidence for water ice near the lunar poles Feldman, W. C.; Maurice, S.; Lawrence, D. J. ...
Journal of Geophysical Research,
25 October 2001, Letnik:
106, Številka:
E10
Journal Article, Conference Proceeding
Recenzirano
Odprti dostop
Improved versions of Lunar Prospector thermal and epithermal neutron data were studied to help discriminate between potential delivery and retention mechanisms for hydrogen on the Moon. Improved ...spatial resolution at both poles shows that the largest concentrations of hydrogen overlay regions in permanent shade. In the north these regions consist of a heavily cratered terrain containing many small (less than ∼10‐km diameter), isolated craters. These border circular areas of hydrogen abundance (H) that is only modestly enhanced above the average equatorial value but that falls within large, flat‐bottomed, and sunlit polar craters. Near the south pole, H is enhanced within several 30‐km‐scale craters that are in permanent shade but is only modestly enhanced within their sunlit neighbors. We show that delivery by the solar wind cannot account for these observations because the diffusivity of hydrogen at the temperatures within both sunlit and permanently shaded craters near both poles is sufficiently low that a solar wind origin cannot explain their differences. We conclude that a significant portion of the enhanced hydrogen near both poles is most likely in the form of water molecules.
Autonomous mobile-manipulation robots need to sense and interact with objects to accomplish high-level tasks such as preparing meals and searching for objects. To achieve such tasks, robots need ...semantic world models, defined as object-based representations of the world involving task-level attributes. In this work, we address the problem of estimating world models from semantic perception modules that provide noisy observations of attributes. Because attribute detections are sparse, ambiguous, and are aggregated across different viewpoints, it is unclear which attribute measurements are produced by the same object, so data association issues are prevalent. We present novel clustering-based approaches to this problem, which are more efficient and require less severe approximations compared with existing tracking-based approaches. These approaches are applied to data containing object type-and-pose detections from multiple viewpoints, and demonstrate comparable quality using a fraction of the computation time.
We study the task of locating a user in a mapped indoor environment using natural language queries and images from the environment. Building on recent pretrained vision-language models, we learn a ...similarity score between text descriptions and images of locations in the environment. This score allows us to identify locations that best match the language query, estimating the user's location. Our approach is capable of localizing on environments, text, and images that were not seen during training. One model, finetuned CLIP, outperformed humans in our evaluation.
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