Abstract
The GLASS-JWST Early Release Science (hereafter GLASS-JWST-ERS) Program will obtain and make publicly available the deepest extragalactic data of the ERS campaign. It is primarily designed ...to address two key science questions, namely, “what sources ionized the universe and when?” and “how do baryons cycle through galaxies?”, while also enabling a broad variety of first look scientific investigations. In primary mode, it will obtain NIRISS and NIRSpec spectroscopy of galaxies lensed by the foreground Hubble Frontier Field cluster, Abell 2744. In parallel, it will use NIRCam to observe two fields that are offset from the cluster center, where lensing magnification is negligible, and which can thus be effectively considered blank fields. In order to prepare the community for access to this unprecedented data, we describe the scientific rationale, the survey design (including target selection and observational setups), and present pre-commissioning estimates of the expected sensitivity. In addition, we describe the planned public releases of high-level data products, for use by the wider astronomical community.
Liquid metal is used to tune the operational frequency of a monopole antenna by adjusting its length. The centre frequency can be continuously tuned over two octaves, 2.0–9.5 GHz, while maintaining a ...gain of ∼5.2 dBi.
809 deep IODP Hole U1473A at Atlantis Bank, SWIR, is 2.2 km from 1,508‐m Hole 735B and 1.4 from 158‐m Hole 1105A. With mapping, it provides the first 3‐D view of the upper levels of a 660‐km2 lower ...crustal batholith. It is laterally and vertically zoned, representing a complex interplay of cyclic intrusion, and ongoing deformation, with kilometer‐scale upward and lateral migration of interstial melt. Transform wall dives over the gabbro‐peridotite contact found only evolved gabbro intruded directly into the mantle near the transform. There was no high‐level melt lens, rather the gabbros crystallized at depth, and then emplaced into the zone of diking by diapiric rise of a crystal mush followed by crystal‐plastic deformation and faulting. The residues to mass balance the crust to a parent melt composition lie at depth below the center of the massif—likely near the crust‐mantle boundary. Thus, basalts erupted to the seafloor from >1,550 mbsf. By contrast, the Mid‐Atlantic Ridge lower crust drilled at 23°N and at Atlantis Massif experienced little high‐temperature deformation and limited late‐stage melt transport. They contain primitive cumulates and represent direct intrusion, storage, and crystallization of parental MORB in thinner crust below the dike‐gabbro transition. The strong asymmetric spreading of the SWIR to the south was due to fault capture, with the northern rift valley wall faults cutoff by a detachment fault that extended across most of the zone of intrusion. This caused rapid migration of the plate boundary to the north, while the large majority of the lower crust to spread south unroofing Atlantis Bank and uplifting it into the rift mountains.
Key Points
No evidence of a high‐level melt lens with gabbros intruded at depth, then emplaced to high levels by crystal mush diapirism, plastic deformation, and faulting
Diving over the crust‐mantle boundary on the transform wall found no primitive cumulates, and evolved gabbro was intruded directly into the mantle at the transform
Primitive cumulates needed to mass balance MORB must lie at depth near the crust‐mantle boundary, while the few diabase dikes encountered intrude the gabbro
Liquid metal actuated by pressure-driven air bubbles is guided within channels to dynamically reconfigure the length of the radiating aperture and feed line of a slot antenna. The gallium-based ...liquid metal is held in position by air bubbles, and liquid-metal motion is induced when a pressure differential is created. In contrast to conventional hydraulic or pneumatic actuation of gallium-based liquid metal, the pressure actuation described here is reversible and repeatable, as the liquid metal is enveloped by a thin layer of NaOH solution, which acts as a slip layer and reduces any metal oxidation. The slot antenna achieves a 26% tunable bandwidth with a contiguous range from 1.42 to 1.84 GHz for which the S11 is <−10 dB. The peak gain ranges from 4.8 dBi in its lowest-frequency state to 4.1 dBi in its highest-frequency state.
A frequency-tunable microstrip patch antenna with a liquid-metal-actuated loading slot is presented. The electrical length of the loading slot located beneath the resonating patch is altered by ...filling and evacuating liquid metal from fluidic channels along the ground plane. The slot reactively loads the antenna, altering the resonant frequency as its length is changed. Frequency tuning is achieved from 1.85 to 2.07 GHz, corresponding to an 11.2% tuning bandwidth.
Using the Hubble Space Telescope/Wide Field Camera 3 imaging data and multi-wavelength photometric catalog, we investigated the dust temperature of passively evolving and star-forming galaxies at 0.2 ...< z < 1.0 in the CANDELS fields. We estimated the stellar radiation field by low-mass stars from the stellar mass and surface brightness profile of these galaxies and then calculated their steady-state dust temperature. At first, we tested our method using nearby early-type galaxies with the deep far-IR data by the Herschel Virgo cluster survey and confirmed that the estimated dust temperatures are consistent with the observed temperatures within the uncertainty. We then applied the method to galaxies at 0.2 < z < 1.0, and found that most passively evolving galaxies with M sub(star) > 10 super(10) M sub(middot in circle) have relatively high dust temperatures of T sub(dust) > 20 K, for which the formation efficiency of molecular hydrogen on the surface of dust grains in the diffuse ISM is expected to be very low from the laboratory experiments. The fraction of passively evolving galaxies strongly depends on the expected dust temperature at all redshifts and increases rapidly increasing temperature around T sub(dust) > 20 K. These results suggest that the dust heating by low-mass stars in massive galaxies plays an important role in the continuation of their passive evolution because the lack of the shielding effect of the molecular hydrogen on the UV radiation can prevent the gas cooling and formation of new stars.
The mantle section of the central Palawan Ophiolite (CPO) in western Philippines is dominantly composed of dunites and harzburgites. Basal lherzolites and harzburgites juxtaposed with the metamorphic ...sole of the CPO are also exposed within the vicinity of Ulugan Bay, Puerto Princesa. These basal peridotites provide novel information regarding the processes transpiring in the upper mantle during the evolution of this preserved oceanic lithosphere. The Nasuduan lherzolite is characterized by low Cr# of spinel and high concentrations of REEs in clinopyroxenes. The Oyster Bay lherzolite displays similar fertile characteristics and occurs with harzburgites. Both contain fine-grained and interstitial clinopyroxenes derived from interstitial melts. Tremolite and talc in the Oyster Bay lherzolite and harzburgite and in other CPO harzburgites are attributed to slab-fluid metasomatism. Harzburgites and dunites from Bentoan Beach and other CPO harzburgites have high spinel Cr# and low clinopyroxene REE concentrations. These indicate that these peridotites have undergone extensive degrees of melting facilitated by fluids. The petrological and geochemical signatures of the CPO peridotites record the transition of a supra-subduction zone from back-arc spreading, incipient subduction, to the obduction of an ancient oceanic lithosphere.
The escape fraction of Lyman-continuum (LyC) photons (
f
esc
) is a key parameter for determining the sources of cosmic reionization at
z
≥ 6. At these redshifts, owing to the opacity of the ...intergalactic medium, the LyC emission cannot be measured directly. However, LyC leakers during the epoch of reionization could be identified using indirect indicators that have been extensively tested at low and intermediate redshifts. These include a high O
III
/O
II
flux ratio, high star-formation surface density, and compact sizes. In this work, we present observations of 29 4.5 ≤
z
≤ 8 gravitationally lensed galaxies in the Abell 2744 cluster field. From a combined analysis of JWST-NIRSpec and NIRCam data, we accurately derived their physical and spectroscopic properties: our galaxies have low masses (log(
M
⋆
)∼8.5), blue UV spectral slopes (
β
∼ −2.1), compact sizes (
r
e
∼ 0.3 − 0.5 kpc), and high O
III
/O
II
flux ratios. We confirm that these properties are similar to those characterizing low-redshift LyC leakers. Indirectly inferring the fraction of escaping ionizing photons, we find that more than 80% of our galaxies have predicted
f
esc
values larger than 0.05, indicating that they would be considered leakers. The average predicted
f
esc
value of our sample is 0.12, suggesting that similar galaxies at
z
≥ 6 have provided a substantial contribution to cosmic reionization.
The goal of oral insulin delivery devices is to protect the sensitive drug from proteolytic degradation in the stomach and upper portion of the small intestine. In this work, we investigate the use ...of pH‐responsive, poly(methacrylic‐g‐ethylene glycol) hydrogels as oral delivery vehicles for insulin. Insulin was loaded into polymeric microspheres and administered orally to healthy and diabetic Wistar rats. In the acidic environment of the stomach, the gels were unswollen due to the formation of intermolecular polymer complexes. The insulin remained in the gel and was protected from proteolytic degradation. In the basic and neutral environments of the intestine, the complexes dissociated which resulted in rapid gel swelling and insulin release. Within 2 h of administration of the insulin‐containing polymers, strong dose‐dependent hypoglycemic effects were observed in both healthy and diabetic rats. These effects lasted for up to 8 h following administration.
Hydrogels of poly(methacrylic acid-g-ethylene glycol) were prepared using different reaction water contents in order to vary the network mesh size, swelling behavior and insulin loading/release ...kinetics. Gels prepared with greater reaction solvent contents swelled to a greater degree and had a larger network mesh size. All of the hydrogels were able to incorporate insulin and protected it from release in acidic media. At higher pH (7.4), the release rates increased with reaction solvent content. Using a closed loop animal model, all of the insulin loaded formulations produced significant insulin absorption in the upper small intestine combined with hypoglycemic effects. In these studies, bioavailabilities ranged from 4.6% to 7.2% and were dependent on reaction solvent content.
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