Pattern printing techniques have advanced rapidly in the past decade, driven by their potential applications in printed electronics. Several printing techniques have realized printed features of 10 ...μm or smaller, but unfortunately, they suffer from disadvantages that prevent their deployment in real applications; in particular, process throughput is a significant concern. Direct gravure printing is promising in this regard. Gravure printing delivers high throughput and has a proven history of being manufacturing worthy. Unfortunately, it suffers from scalability challenges because of limitations in roll manufacturing and limited understanding of the relevant printing mechanisms. Gravure printing involves interactions between the ink, the patterned cylinder master, the doctor blade that wipes excess ink, and the substrate to which the pattern is transferred. As gravure-printed features are scaled, the associated complexities are increased, and a detailed study of the various processes involved is lacking. In this work, we report on various gravure-related fluidic mechanisms using a novel highly scaled inverse direct gravure printer. The printer allows the overall pattern formation process to be studied in detail by separating the entire printing process into three sequential steps: filling, wiping, and transferring. We found that pattern formation by highly scaled gravure printing is governed by the wettability of the ink to the printing plate, doctor blade, and substrate. These individual functions are linked by the apparent capillary number (Ca); the printed volume fraction (φp) of a feature can be constructed by incorporating these basis functions. By relating Ca and φp, an optimized operating point can be specified, and the associated limiting phenomena can be identified. We used this relationship to find the optimized ink viscosity and printing speed to achieve printed polymer lines and line spacings as small as 2 μm at printing speeds as high as ∼1 m/s.
We present the results from extensive, new observations of the Perseus Cluster of galaxies, obtained as a Suzaku Key Project. The 85 pointings analysed span eight azimuthal directions out to 2° = 2.6 ...Mpc, to and beyond the virial radius r
200 ∼ 1.8 Mpc, offering the most detailed X-ray measurements of the intracluster medium (ICM) at large radii in any cluster to date. The azimuthally averaged density profile for r > 0.4r
200 is relatively flat, with a best-fitting power-law index δ = 1.69 ± 0.13, significantly smaller than expected from numerical simulations. The entropy profile in the outskirts lies systematically below the power-law behaviour expected from large-scale structure formation models which include only the heating associated with gravitational collapse. Conversely, the pressure profile beyond ∼0.6r
200 shows an excess with respect to the best-fitting model describing the SZ measurements for a sample of clusters observed with the Planck satellite. The differences between the expected and measured density, entropy and pressure profiles can be explained by a systematic overestimation of the ICM density at large radii caused by homogeneous modelling of inhomogeneous gas distributions (i.e. gas clumping), with the density overestimates ranging from factors of ∼1.2 to 2 or more at r
200 along different directions. We find no evidence for a bias in the temperature measurements within the virial radius. Along the cluster minor axis, we find a flattening of the entropy profiles outside ∼0.6r
200, while along the major axis, the entropy rises all the way to the outskirts.
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•We inkjet-print square drops onto roughened glass.•We demonstrate that increasing roughness leads to sharper drop corners.•We simulate drops to link contact angle hysteresis and drop ...corner fidelity.
Motivated by the process of inkjet printing of electronics, we study experimentally and theoretically the processes limiting the printing of sharply defined, equilibrium corners. Using a non-volatile ionic liquid, we inkjet print squares with rounded corners on a substrate of roughened, display-grade glass. We show experimentally that with increasing roughness, corner radius decreases, allowing more precisely defined features to be printed. To interpret these results in terms of contact-angle hysteresis (difference between the advancing and retreating contact angles θA and θR), we implement the following model with the Surface Evolver program. With drop volume fixed, we minimize drop surface energy subject to a prescribed contact line. We identify θA and θR as the minimum and maximum contact angles around the drop perimeter. We find that with decreasing corner fidelity, contact-angle hysteresis also decreases. We are thus able to infer θR from the corner radius of printed features. We conclude that increasing contact-angle hysteresis allows the printing of more precisely defined features.
Lysophosphatidic acid (LPA) stimulates Rho GTPase and its effector, the formin mDia, to capture and stabilize microtubules in fibroblasts. We investigated whether mammalian EB1 and adenomatous ...polyposis coli (APC) function downstream of Rho-mDia in microtubule stabilization. A carboxy-terminal APC-binding fragment of EB1 (EB1-C) functioned as a dominant-negative inhibitor of microtubule stabilization induced by LPA or active mDia. Knockdown of EB1 with small interfering RNAs also prevented microtubule stabilization. Expression of either full-length EB1 or APC, but not an APC-binding mutant of EB1, was sufficient to stabilize microtubules. Binding and localization studies showed that EB1, APC and mDia may form a complex at stable microtubule ends. Furthermore, EB1-C, but not an APC-binding mutant, inhibited fibroblast migration in an in vitro wounding assay. These results show an evolutionarily conserved pathway for microtubule capture, and suggest that mDia functions as a scaffold protein for EB1 and APC to stabilize microtubules and promote cell migration.
Atypical parkinsonian syndromes (APS), including progressive supranuclear palsy (PSP), corticobasal syndrome (CBS), and multiple system atrophy (MSA), may be difficult to distinguish in early stages ...and are often misdiagnosed as Parkinson disease (PD). The diagnostic criteria for PSP have been updated to encompass a range of clinical subtypes but have not been prospectively studied.
To define the distinguishing features of PSP and CBS subtypes and to assess their usefulness in facilitating early diagnosis and separation from PD.
This cohort study recruited patients with APS and PD from movement disorder clinics across the United Kingdom from September 1, 2015, through December 1, 2018. Patients with APS were stratified into the following groups: those with Richardson syndrome (PSP-RS), PSP-subcortical (including PSP-parkinsonism and progressive gait freezing subtypes), PSP-cortical (including PSP-frontal and PSP-CBS overlap subtypes), MSA-parkinsonism, MSA-cerebellar, CBS-Alzheimer disease (CBS-AD), and CBS-non-AD. Data were analyzed from February 1, through May 1, 2019.
Baseline group comparisons used (1) clinical trajectory; (2) cognitive screening scales; (3) serum neurofilament light chain (NF-L) levels; (4) TRIM11, ApoE, and MAPT genotypes; and (5) volumetric magnetic resonance imaging measures.
A total of 222 patients with APS (101 with PSP, 55 with MSA, 40 with CBS, and 26 indeterminate) were recruited (129 58.1% male; mean SD age at recruitment, 68.3 8.7 years). Age-matched control participants (n = 76) and patients with PD (n = 1967) were included for comparison. Concordance between the antemortem clinical and pathologic diagnoses was achieved in 12 of 13 patients with PSP and CBS (92.3%) undergoing postmortem evaluation. Applying the Movement Disorder Society PSP diagnostic criteria almost doubled the number of patients diagnosed with PSP from 58 to 101. Forty-nine of 101 patients with reclassified PSP (48.5%) did not have the classic PSP-RS subtype. Patients in the PSP-subcortical group had a longer diagnostic latency and a more benign clinical trajectory than those in PSP-RS and PSP-cortical groups. The PSP-subcortical group was distinguished from PSP-cortical and PSP-RS groups by cortical volumetric magnetic resonance imaging measures (area under the curve AUC, 0.84-0.89), cognitive profile (AUC, 0.80-0.83), serum NF-L level (AUC, 0.75-0.83), and TRIM11 rs564309 genotype. Midbrain atrophy was a common feature of all PSP groups. Eight of 17 patients with CBS (47.1%) undergoing cerebrospinal fluid analysis were identified as having the CBS-AD subtype. Patients in the CBS-AD group had a longer diagnostic latency, relatively benign clinical trajectory, greater cognitive impairment, and higher APOE-ε4 allele frequency than those in the CBS-non-AD group (AUC, 0.80-0.87; P < .05). Serum NF-L levels distinguished PD from all PSP and CBS cases combined (AUC, 0.80; P < .05).
These findings suggest that studies focusing on the PSP-RS subtype are likely to miss a large number of patients with underlying PSP tau pathology. Analysis of cerebrospinal fluid defined a distinct CBS-AD subtype. The PSP and CBS subtypes have distinct characteristics that may enhance their early diagnosis.
Brief measures that accurately discriminate normal cognitive aging from very mild dementia are lacking. Cognitive tests often are insensitive to very mild dementia. Informant-based measures may be ...more sensitive in detecting early dementia.
To identify informant-reported clinical variables that differentiate cognitively normal individuals from those with very mild dementia.
A 55-item battery of informant queries regarding an individual's cognitive status was derived from a semistructured interview and a consensus panel of dementia experts. The battery was evaluated with informants for 189 consecutive participants of a longitudinal study of memory and aging and compared with an independently obtained Clinical Dementia Rating (CDR) score for the participant. Multiple regression and receiver operator characteristic curves assessed subsets of the items to discriminate between CDR 0 (no dementia) and CDR 0.5 (very mild dementia).
The final version (AD8) querying memory, orientation, judgment, and function was administered to an additional sample of 112 CDR 0 and 68 CDR 0.5 participants. Using a cut-off of two items endorsed, the area under the curve was 0.834, suggesting good to excellent discrimination, sensitivity was 74%, and specificity was 86% (prevalence of 0.38 for very mild dementia). Inclusion of 56 additional individuals with mild to severe dementia (increasing dementia prevalence to 0.53) increased sensitivity to 85%.
The AD8 is a brief, sensitive measure that reliably differentiates between nondemented and demented individuals. Use of the AD8 in conjunction with a brief assessment of the participant could improve diagnostic accuracy in general practice.
Motivated by experiments showing that a sessile drop of volatile perfectly wetting liquid initially advances over the substrate, but then reverses, we formulate the problem describing the contact ...region at reversal. Assuming a separation of scales, so that the radial extent of this region is small compared with the instantaneous radius
$a$
of the apparent contact line, we show that the time scale characterizing the contact region is small compared with that on which the bulk drop is evolving. As a result, the contact region is governed by a boundary-value problem, rather than an initial-value problem: the contact region has no memory, and all its properties are determined by conditions at the instant of reversal. We conclude that the apparent contact angle
$\theta $
is a function of the instantaneous drop radius
$a$
, as found in the experiments. We then non-dimensionalize the boundary-value problem, and find that its solution depends on one parameter
$\mathscr{L}$
, a dimensionless surface tension. According to this formulation, the apparent contact angle is well-defined: at the outer edge of the contact region, the film slope approaches a limit that is independent of the curvature of bulk drop. In this, it differs from the dynamic contact angle observed during spreading of non-volatile drops. Next, we analyse the boundary-value problem assuming
$\mathscr{L}$
to be small. Though, for arbitrary
$\mathscr{L}$
, determining
$\theta $
requires solving the steady diffusion equation for the vapour, there is, for small
$\mathscr{L}$
, a further separation of scales within the contact region. As a result,
$\theta $
is now determined by solving an ordinary differential equation. We predict that
$\theta $
varies as
${a}^{- 1/ 6} $
, as found experimentally for small drops (
$a\lt 1~\mathrm{mm} $
). For these drops, predicted and measured angles agree to within 10–30 %. Because the discrepancy increases with
$a$
, but
$\mathscr{L}$
is a decreasing function of
$a$
, we infer that some process occurring outside the contact region is required to explain the observed behaviour of larger drops having
$a\gt 1~\mathrm{mm} $
.
Inkjet printing of precisely defined structures is critical for the realization of a range of printed electronics applications. We develop and demonstrate a methodology to optimize the inkjet ...printing of two-dimensional, partially wetting films. When printed inks have a positive retreating contact angle, we show that any fixed spacing is ineffective for printing two-dimensional features. With fixed spacing, the bead contact angle begins large, leading to a bulging overflow of its intended footprint. Each additional line reduces the bead contact angle, eventually leading to separation of the bead. We propose a printing scheme that adjusts the line-to-line spacing to maintain a bead’s contact angle between its advancing and retreating values as it is printed. Implementing this approach requires an understanding of the two-dimensional bead surface and compensation for evaporation during the print. We derive an analytic equation for the bead’s surface with pinned contact lines and use an empirical fit for mass loss due to evaporation. Finally, we demonstrate that enhanced contact angle hysteresis, achieved by preprinting a feature’s border, leads to better corner definition.
Modified clay minerals on Mars
Sedimentary rocks exposed in Gale crater on Mars contain extensive clay minerals. Bristow
et al.
analyzed drill samples collected by the Curiosity rover as it climbed ...up sedimentary layers in the crater. They found evidence of past reactions with liquid water and sulfate brines, which could have percolated through the clay from an overlying sulfate deposit. Similar sulfate deposits are widespread across the planet and represent some of the last sedimentary rocks to form before the planet lost its surface liquid water, so the results inform our understanding of the geologic processes that occurred as Mars dried out.
Science, abg5449, this issue p.
198
Clay minerals examined by the Curiosity rover contain evidence of reactions with sulfate brines as Mars dried out.
Mars’ sedimentary rock record preserves information on geological (and potential astrobiological) processes that occurred on the planet billions of years ago. The
Curiosity
rover is exploring the lower reaches of Mount Sharp, in Gale crater on Mars. A traverse from Vera Rubin ridge to Glen Torridon has allowed
Curiosity
to examine a lateral transect of rock strata laid down in a martian lake ~3.5 billion years ago. We report spatial differences in the mineralogy of time-equivalent sedimentary rocks <400 meters apart. These differences indicate localized infiltration of silica-poor brines, generated during deposition of overlying magnesium sulfate–bearing strata. We propose that destabilization of silicate minerals driven by silica-poor brines (rarely observed on Earth) was widespread on ancient Mars, because sulfate deposits are globally distributed.
Bipolar disorder is a heritable mental illness with complex etiology. We performed a genome-wide association study of 41,917 bipolar disorder cases and 371,549 controls of European ancestry, which ...identified 64 associated genomic loci. Bipolar disorder risk alleles were enriched in genes in synaptic signaling pathways and brain-expressed genes, particularly those with high specificity of expression in neurons of the prefrontal cortex and hippocampus. Significant signal enrichment was found in genes encoding targets of antipsychotics, calcium channel blockers, antiepileptics and anesthetics. Integrating expression quantitative trait locus data implicated 15 genes robustly linked to bipolar disorder via gene expression, encoding druggable targets such as HTR6, MCHR1, DCLK3 and FURIN. Analyses of bipolar disorder subtypes indicated high but imperfect genetic correlation between bipolar disorder type I and II and identified additional associated loci. Together, these results advance our understanding of the biological etiology of bipolar disorder, identify novel therapeutic leads and prioritize genes for functional follow-up studies.
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