TL;DR: The first continuous, multi-century and observationally constrained record of GrIS surface melt intensity and runoff is presented, revealing that the magnitude of recent GrIS melting is exceptional over at least the last 350 years.
Abstract: The Greenland ice sheet (GrIS) is a growing contributor to global sea-level rise1, with recent ice mass loss dominated by surface meltwater runoff2,3. Satellite observations reveal positive trends in GrIS surface melt extent4, but melt variability, intensity and runoff remain uncertain before the satellite era. Here we present the first continuous, multi-century and observationally constrained record of GrIS surface melt intensity and runoff, revealing that the magnitude of recent GrIS melting is exceptional over at least the last 350 years. We develop this record through stratigraphic analysis of central west Greenland ice cores, and demonstrate that measurements of refrozen melt layers in percolation zone ice cores can be used to quantifiably, and reproducibly, reconstruct past melt rates. We show significant (P < 0.01) and spatially extensive correlations between these ice-core-derived melt records and modelled melt rates5,6 and satellite-derived melt duration4 across Greenland more broadly, enabling the reconstruction of past ice-sheet-scale surface melt intensity and runoff. We find that the initiation of increases in GrIS melting closely follow the onset of industrial-era Arctic warming in the mid-1800s, but that the magnitude of GrIS melting has only recently emerged beyond the range of natural variability. Owing to a nonlinear response of surface melting to increasing summer air temperatures, continued atmospheric warming will lead to rapid increases in GrIS runoff and sea-level contributions.
TL;DR: In this paper, the disciplinary role of short-maturity debt in cash-rich firms' over-investment in acquisitions is investigated and shown to be mostly concentrated among weakly governed and limited access to the public debt market.
TL;DR: The challenges that loomed the largest for Rwanda's family planning program were service accessibility for rural Rwandans, adolescent access to and use of contraceptives, opposition from religious institutions, as well as inadequate human resources and funding.
Abstract: Rwanda has made significant strides in improving the health of its people, including increasing access to and use of family planning. Contraceptive use has increased from 17% to 53% in just one decade, from 2005 to 2015. The data consist of 13 in-depth interviews conducted with family planning program experts in Rwanda to better understand the mechanisms for success, elucidate remaining challenges, speculate on the future of the program, and discuss potential applicability for translating aspects of the program in other settings. All respondents first noted the positive aspects of government will, leadership, and management of the family planning program when asked to describe the reasons for success. The challenges that loomed the largest for the program were service accessibility for rural Rwandans, adolescent access to and use of contraceptives, opposition from religious institutions, as well as inadequate human resources and funding. These challenges were openly acknowledged and are in the process of being addressed. The importance of government leadership and focus in the success of Rwanda’s family planning program was prominent. All positive aspects of the program are based upon the strong foundation the government has built and nurtured. Since innovation is welcomed and program evaluation is considered essential, the outlook for Rwanda’s family planning program is favorable. The issues that remain are common and persistent challenges for family planning programs. Other nations could learn tangible practices from Rwanda’s success and follow Rwanda’s efforts to mitigate the remaining challenges.
TL;DR: In this article, the authors performed detailed mapping at nine sites using Galileo and Voyager imagery, noting key examples of strike-slip morphologies where present, including en echelon structures, strikeslip duplexes, laterally offset pre-existing features, and possible strained craters.
TL;DR: In this paper, Cayley and Klein used linear algebra and transformation groups to construct "linear" and "circular" geometries, including Euclidean, hyperbolic, elliptic, and spherical.
Abstract: Euclidean and other geometries are distinguished by the transformations that preserve their essential properties. Using linear algebra and transformation groups, this book provides a readable exposition of how these classical geometries are both differentiated and connected. Following Cayley and Klein, the book builds on projective and inversive geometry to construct 'linear' and 'circular' geometries, including classical real metric spaces like Euclidean, hyperbolic, elliptic, and spherical, as well as their unitary counterparts. The first part of the book deals with the foundations and general properties of the various kinds of geometries. The latter part studies discrete-geometric structures and their symmetries in various spaces. Written for graduate students, the book includes numerous exercises and covers both classical results and new research in the field. An understanding of analytic geometry, linear algebra, and elementary group theory is assumed.
TL;DR: In this paper, a new global photogrammetric control network for Enceladus was proposed to support geologic mapping and other investigations using the data from NASA's Cassini spacecraft.
Abstract: NASA’s Cassini spacecraft spent 13 years exploring the Saturn system, including 23 targeted
flybys of the small, geologically active moon Enceladus. These flybys provided a wealth of image data
from Cassini’s Imaging Science Subsystem. To improve the usability of the Enceladus data set, we created
a new, global photogrammetric control network for Enceladus that enabled compilation of a versatile
cartographic package to support geologic mapping and other investigations. The network used
586 images in four image filters with a pixel scale generally between 50 and 500 m per pixel and a phase
angle less than 120° and consisted of 10,362 tie points and 173,704 individual image measures, averaging
nearly 17 measures per tie point. Least squares bundle adjustment resulted in a root-mean-square
residual of 0.45 pixel, corresponding to root-mean-square ground point uncertainties of 66, 51, and 46 m
in latitude, longitude, and radius, respectively. Using our geodetic control network, we created new global
image mosaics, coregistered flyby mosaics to support geologic mapping, and updated pointing kernels
for every image used in the solution. These products, including the updated pointing kernels, are
available to the community through NASA’s Planetary Data System Imaging Annex. The bundle
adjustment solution also yielded independently determined shape information, resulting in radii within
the stated uncertainty of International Astronomical Union values. The challenges of the data set, and the
technical methodology described here are applicable to bodies imaged during multiple flybys with
variable viewing and illumination geometry, including other midsized satellites of Saturn, and the Europa
Clipper mission.
TL;DR: Black Panther has been a critical and financial success and a defining moment for black storytelling in Hollywood as discussed by the authors, it is the first superhero movie with a predominantly black creative team and cas...
Abstract: Black Panther has been a critical and financial success and a defining moment for black storytelling in Hollywood. This is the first superhero movie with a predominantly black creative team and cas...
TL;DR: In this article, the singularity properties of 2-step nilpotent Lie algebras are studied in terms of a simple directed graph, where conditions are given on the graph and on a lattice.
Abstract: Dani and Mainkar introduced a method for constructing a 2-step nilpotent Lie algebra $\mathfrak{n}_G$ from a simple directed graph $G$ in 2005. There is a natural inner product on $\mathfrak{n}_G$ arising from the construction. We study geometric properties of the associated simply connected 2-step nilpotent Lie group $N$ with Lie algebra $\mathfrak{n}_G$. We classify singularity properties of the Lie algebra $\mathfrak{n}_G$ in terms of the graph $G$. A comprehensive description is given of graphs $G$ which give rise to Heisenberg-like Lie algebras. Conditions are given on the graph $G$ and on a lattice $\Gamma \subseteq N$ for which the quotient $\Gamma \backslash N$, a compact nilmanifold, has a dense set of smoothly closed geodesics.
TL;DR: In this paper, the crystal structure, microstructure and performance of nanostructured powders with nominal composition Y4Zr3O12, undoped and doped at Yb3+ 1
TL;DR: In this paper, the authors examined the impact of ICT on community bonds and boundaries in the mountain biking community and found that online and in-person communication intersect to blur the distinction between strong and weak ties, make the boundaries of the community more porous, and accelerate the development of trust between members.
Abstract: The affordances of new information and communication technologies (ICTs) have altered the ways that communities emerge, interact, and organize, creating possibilities for new forms of interaction. Using a case study of the mountain biking community, this paper examines the impact of ICTs on community bonds and boundaries. Based on 60 intensive interviews in North America, survey results from 2363 mountain bikers around the world, and email exchanges with an addition 98 of the survey respondents, the findings suggest several ways that online and in-person communication intersect to blur the distinction between strong and weak ties, make the boundaries of the community more porous, and accelerate the development of trust between members.
TL;DR: It is suggested that negative and positive aspects of the self are partially dissociable and positively associated with narcissistic traits, and negatively associated with depressive symptom severity only.
Abstract: Adolescence is a period of significant identity development and particular vulnerability to depression associated with negative self-evaluation. We investigated if increased depressive symptom severity was also associated with positive self-evaluation. We also considered pubertal developmental differences in positive and negative self-evaluation, and if these could reflect dissociated facets of the self. This cross-sectional sample consisted of healthy male and female adolescents ( N = 109) aged 12–17 from the United States. Participants completed a self-referential encoding task, which required them to indicate if a single-word adjective was self-descriptive. We administered the Children’s Depression Inventory, the Pubertal Development Scale, and the Child Narcissism Scale. Negative-word endorsement was significantly predicted by pubertal maturation level and depressive symptoms, but not by narcissism. Positive-word endorsement was significantly predicted by narcissism and negatively predicted by depressive symptoms, but not by pubertal maturation. In this typically developing sample, positive self-judgment does not vary across the pubertal range and is positively associated with narcissistic traits, and negatively associated with depressive symptom severity. Negative self-judgements are positively correlated with puberty and are associated with depressive symptom severity only. Our findings suggest that negative and positive aspects of the self are partially dissociable.
TL;DR: In this paper, the authors argue that Astell's theory of friendship is determinedly anti-Aristotelian; it is a theory of spiritual friendship offered as an alternative to Aristotelians' virtue friendship.
Abstract: Mary Astell’s theory of friendship has been interpreted either as a version of Aristotelian virtue friendship, or as aligned with a Christian and Platonist tradition. In this paper, I argue that Astell’s theory of friendship is determinedly anti-Aristotelian; it is a theory of spiritual friendship offered as an alternative to Aristotelian virtue friendship. By grounding her conception of friendship in a Christian–Platonist metaphysics, I show that Astell rejects the Aristotelian criteria of reciprocity and partiality as essential features of the friendship bond and that she develops a theory of friendship that is neither reciprocal nor partial. Further, I argue that Astell’s theory of friendship advances her feminist aims by providing a justification for female–female spiritual bonds in contradistinction to female–male marriage bonds. Astell argues that the female–female bond of spiritual friendship is sanctioned by God, and is, therefore, a divinely authorized alternative to the male–female bond ...
TL;DR: Since methylmercury output did not increase and nitrate removal was not permanently affected, PRBs could be a low cost approach to combat eutrophication.
TL;DR: It is demonstrated that altering any sensory system impacts landing behavior, though loss of vision had the least effect and the fact that no ablation entirely eliminates all aspects of landing preparation suggests that its underpinnings are complex and that there is no single sensory trigger for its initiation.
Abstract: Coordinated landing from a jump requires preparation, which must include appropriate positioning and configuration of the landing limbs and body to be successful. While well studied in mammals, our lab has been using the cane toad (Rhinella marinus) as a model for understanding the biomechanics of controlled landing in anurans, animals that use jumping or bounding as their dominant mode of locomotion. In this article, we report new results from experiments designed to explore how different modes of sensory feedback contribute to previously identified features of coordinated landing in toads. More specifically, animals in which vision, hindlimb proprioception, or vestibular feedback were removed, underwent a series of hopping trials while high-speed video was used to record and characterize limb movements and electromyographic (EMG) activity was recorded from a major elbow extensor (anconeus). Results demonstrate that altering any sensory system impacts landing behavior, though loss of vision had the least effect. Blind animals showed significant differences in anconeus EMG timing relative to controls, but forelimb and hindlimb movements as well as the ability to successfully decelerate the body using the forelimbs were not affected. Compromising hindlimb proprioception led to distinctly different forelimb kinematics. Though EMG patterns were disrupted, animals in this condition were also able to decelerate after impact, though with less control, regularly allowing their trunks to make ground contact during landing. Animals with compromised vestibular systems showed the greatest deficits, both in takeoff and landing behavior, which were highly variable and rarely coordinated. Nevertheless, animals in this condition demonstrated EMG patterns and forelimb kinematics similar to those in control animals. The fact that no ablation entirely eliminates all aspects of landing preparation suggests that its underpinnings are complex and that there is no single sensory trigger for its initiation.
TL;DR: In this paper, the Declination metric is used to detect partisan gerrymandering, and it is shown that Declination cannot detect all forms of packing and cracking, and compared to the Efficiency Gap.
Abstract: We explore the Declination, a new metric intended to detect partisan gerrymandering. We consider instances in which each district has equal turnout, the maximum turnout to minimum turnout is bounded, and turnout is unrestricted. For each of these cases, we show exactly which vote-share, seat-share pairs $(V,S)$ have an election outcome with Declination equal to 0. We also show how our analyses can be applied to finding vote-share, seat-share pairs that are possible for nonzero Declination.
Within our analyses, we show that Declination cannot detect all forms of packing and cracking, and we compare the Declination to the Efficiency Gap. We show that these two metrics can behave quite differently, and give explicit examples of that occurring.
TL;DR: This study demonstrates that blind toads are still able to perform coordinated landings, reinforcing the importance of proprioceptive and/or vestibular feedback during hopping, and indicates that vision is more responsible for fine-tuning the motor control strategy for landing.
Abstract: In toad hopping, the hindlimbs generate the propulsive force for take-off while the forelimbs resist the impact forces associated with landing. Preparing to perform a safe landing, in which impact forces are managed appropriately, likely involves the integration of multiple types of sensory feedback. In toads, vestibular and/or proprioceptive feedback is critical for coordinated landing; however, the role of vision remains unclear. To clarify this, we compare pre-landing forelimb muscle activation patterns before and after removing vision. Specifically, we recorded EMG activity from two antagonistic forelimb muscles, the anconeus and coracoradialis, which demonstrate distance-dependent onset timing and recruitment intensity, respectively. Toads were first recorded hopping normally and then again after their optic nerves were severed to remove visual feedback. When blind, toads exhibited hop kinematics and pre-landing muscle activity similar to when sighted. However, distance-dependent relationships for muscle activity patterns were more variable, if present at all. This study demonstrates that blind toads are still able to perform coordinated landings, reinforcing the importance of proprioceptive and/or vestibular feedback during hopping. But the increased variability in distance-dependent activity patterns indicates that vision is more responsible for fine-tuning the motor control strategy for landing.
Abstract: We consider the lifetime of a phosphor layer situated near a metallic film. We first make general observations of the effect of the plasmons on the lifetime and quantum efficiency of the luminescent ions in the phosphor layer and on the role of the plasmons in the emission process. The effect of the plasmons in the excitation process and on the total luminescence from the system is also discussed. We then derive an expression for the lifetime of the optical ions interacting with the surface plasmon modes using the Einstein A and B coefficient formalism, which requires a determination of the mode density of the surface plasmons. Because the surface plasmons represent a 2-dimensional system, a length parameter must be introduced into the expression of the mode density. We derive this parameter using a semi-classical approach, and show its dependence on the dielectric constants of the system and on the distance from the metallic layer.
TL;DR: This paper analyzed public opinion about state parties using an original survey fielded as part of the 2012 Cooperative Congressional Election Study and found limited evidence that ordinary people are responsive to the actual legislative behavior of state parties.
Abstract: Scholarship has established that ideological positions offered by state parties differ substantially from the national parties, and from one another. However, less attention has been devoted to investigating whether ordinary people are aware of the ideological distinctiveness of state parties. In particular, do people notice that their state party is ideologically different than the national party? In this article, I draw upon theories of low information rationality to develop an account of public reasoning about state parties. I analyze public opinion about state parties using an original survey fielded as part of the 2012 Cooperative Congressional Election Study. I find limited evidence that ordinary people are responsive to the actual legislative behavior of state parties. Instead, individuals’ judgments about state party ideology may be rooted in inferences drawn from national-level politics. The findings support arguments that a complicated federal structure obscures the role of state-level actors in the policymaking process.
TL;DR: In this article, the authors explore artistic and activist work that has arisen in response to episodes of violence committed by the apartheid state against anti-apartheid activists and their supporters.
Abstract: This paper explores artistic and activist work that has arisen in response to episodes of violence committed by the apartheid state against anti-apartheid activists. More specifically, it c...
TL;DR: For a dead methodology, it sure is productive as mentioned in this paper... the decline in the academic power and prestige of the discipline, which J.R. Tolkien noted soon after World War I and later lamented in his 19...
Abstract: For a dead methodology, Philology sure is productive.The decline in the academic power and prestige of the discipline, which J.R.R. Tolkien noted soon after World War I and later lamented in his 19...
TL;DR: The New York Intellectuals went from being the intellectual community in U.S. cultural life to a historical coterie with little contemporary relevance over the course of a very few decades.
Abstract: Over the course of a very few decades, the New York Intellectuals went form being the intellectual community in U.S. cultural life to a historical coterie with little contemporary relevance. This article suggests some of the reasons for this evolution, both intellectual and personal.
TL;DR: Two present studies replicated Gelb and Granit’s experiment using a similar figure-ground stimulus albeit with a two-alternative forced choice procedure rather than their original method of adjustment, finding that a detection advantage was found for the figural over the ground region.
Abstract: In 1923, Adhemar Gelb and Ragnar Granit, two prominent researchers in early Gestalt perceptual theory, reported a lower threshold for detection of a target (a small colored dot) on the ground region of an image than on an adjacent figural region. Although their results had a wide influence on the understanding of figure-ground perception, they are at odds with more recent investigations in which figural regions appear to have a processing advantage over ground regions. The two present studies replicated Gelb and Granit's experiment using a similar figure-ground stimulus albeit with a two-alternative forced choice procedure rather than their original method of adjustment. Experiment 1 found that, contrary to Gelb and Granit's findings, a detection advantage was found for the figural over the ground region. Experiment 2 indicated that explicit contours might have played a role in detection.
TL;DR: H1/pHGFK1 exerts anti-tumoural and radiosensitive activities mainly through the inhibition and reversal of IR-induced MET and ATM–Chk2 axis activities in glioblastoma.
Abstract: The therapeutic resistance to ionising radiation (IR) and anti-angiogenesis mainly impair the prognosis of patients with glioblastoma. The primary and secondary MET aberrant activation is one crucial factor for these resistances. The kringle 1 domain of hepatocyte growth factor (HGFK1), an angiogenic inhibitor, contains a high-affinity binding domain of MET; however, its effects on glioblastoma remain elusive. We formed the nanoparticles consisting of a folate receptor-targeted nanoparticle-mediated HGFK1 gene (H1/pHGFK1) and studied its anti-tumoural and radiosensitive activities in both subcutaneous and orthotopic human glioma cell-xenografted mouse models. We then elucidated its molecular mechanisms in human glioblastoma cell lines in vitro. We demonstrated for the first time that peritumoural injection of H1/pHGFK1 nanoparticles significantly inhibited tumour growth and prolonged survival in tumour-bearing mice, as well as enhanced the anti-tumoural efficacies of IR in vivo by reducing Ki-67 expression, enhancing TUNEL staining-indicated apoptotic indexes, reducing microvascular intensity and reversing IR-induced MET overexpression in tumour tissues. Furthermore, we showed that HGFK1 suppressed the proliferation and induced cell apoptosis and enhanced sensitivity to IR in glioblastoma cell lines, mainly by suppressing the activities of MET receptor, down-regulating ATM-Chk2 axis but up-regulating Chk1. H1/pHGFK1 exerts anti-tumoural and radiosensitive activities mainly through the inhibition and reversal of IR-induced MET and ATM–Chk2 axis activities in glioblastoma. H1/pHGFK1 nanoparticles are a potential radiosensitiser and angiogenic inhibitor for glioblastoma treatment.
TL;DR: In this article, Y4Zr3O12 bulk ceramics doped with Yb3+ and Pr3+ were characterized to assess their structural, mechanical, thermal and optical properties.
TL;DR: A direct role for HE4 in mediating malignant properties of ovarian cancer cells is found and the need for HE 4-targeted therapies that will suppress activation of oncogenic transcriptional activation and signaling cascades is validated.
Abstract: Human epididymis protein 4 (HE4) has received much attention recently due to its diagnostic and prognostic abilities for epithelial ovarian cancer. Since its inclusion in the Risk of Ovarian Malignancy Algorithm (ROMA), studies have focused on its functional effects in ovarian cancer. Here, we aimed to investigate the role of HE4 in invasion, haptotaxis, and adhesion of ovarian cancer cells. Furthermore, we sought to gain an understanding of relevant transcriptional profiles and protein kinase signaling pathways mediated by this multifunctional protein. Exposure of OVCAR8 ovarian cancer cells to recombinant HE4 (rHE4) promoted invasion, haptotaxis toward a fibronectin substrate, and adhesion onto fibronectin. Overexpression of HE4 or treatment with rHE4 led to upregulation of several transcripts coding for extracellular matrix proteins, including SERPINB2, GREM1, LAMC2, and LAMB3. Gene ontology indicated an enrichment of terms related to extracellular matrix, cell migration, adhesion, growth, and kinase phosphorylation. LAMC2 and LAMB3 protein levels were constitutively elevated in cells overexpressing HE4 and were upregulated in a time-dependent manner in cells exposed to rHE4 in the media. Deposition of laminin-332, the heterotrimer comprising LAMC2 and LAMB3 proteins, was increased in OVCAR8 cells treated with rHE4 or conditioned media from HE4-overexpressing cells. Enzymatic activity of matriptase, a serine protease that cleaves laminin-332 and contributes to its pro-migratory functional activity, was enhanced by rHE4 treatment in vitro. Proteomic analysis revealed activation of focal adhesion kinase signaling in OVCAR8 cells treated with conditioned media from HE4-overexpressing cells. Focal adhesions were increased in cells treated with rHE4 in the presence of fibronectin. These results indicate a direct role for HE4 in mediating malignant properties of ovarian cancer cells and validate the need for HE4-targeted therapies that will suppress activation of oncogenic transcriptional activation and signaling cascades.
TL;DR: This work proposes that the interaction between Kcnk5b and calcineurin acts as a signaling node to regulate allometric growth, and finds that this regulation is epistatic to inherent mechanisms instructing overall size as inhibition of calcineURin is able to bypass genetic instruction of size as seen in sof and wild-type fins.
Abstract: The establishment of relative size of organs and structures is paramount for attaining final form and function of an organism. Importantly, variation in the proportions of structures frequently underlies adaptive change in morphology in evolution and maybe a common mechanism underlying selection. However, the mechanism by which growth is integrated within tissues during development to achieve proper proportionality is poorly understood. We have shown that signaling by potassium channels mediates coordinated size regulation in zebrafish fins. Recently, calcineurin inhibitors were shown to elicit changes in zebrafish fin allometry as well. Here, we identify the potassium channel kcnk5b as a key player in integrating calcineurin’s growth effects, in part through regulation of the cytoplasmic C-terminus of the channel. We propose that the interaction between Kcnk5b and calcineurin acts as a signaling node to regulate allometric growth. Importantly, we find that this regulation is epistatic to inherent mechanisms instructing overall size as inhibition of calcineurin is able to bypass genetic instruction of size as seen in sof and wild-type fins, however, it is not sufficient to re-specify positional memory of size of the fin. These findings integrate classic signaling mediators such as calcineurin with ion channel function in the regulation of size and proportion during growth.
TL;DR: In this paper, it was shown that these deposits of CH 4 preferentially precipitate at low latitudes where net annual solar energy input is lowest and N 2 will dominate at these low elevations, since there is much more N 2 in the atmosphere than CH 4, so only CH 4 can do so.