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Context. Understanding the earliest stages of star formation, and setting it in the context of the general cycle of matter in the interstellar medium, is a central aspect of research with the James Webb Space Telescope (JWST). Aims. The JWST program JOYS (JWST Observations of Young protoStars) aims to characterize the physical and chemical properties of young high- and low-mass star-forming regions, in particular the unique mid-infrared diagnostics of the warmer gas and solid-state components. We present early results from the high-mass star formation region IRAS 23385+6053. Methods. The JOYS program uses the Mid-Infrared Instrument (MIRI) Medium Resolution Spectrometer (MRS) with its integral field unit (IFU) to investigate a sample of high- and low-mass star-forming protostellar systems. Results. The full 5-? 28 μm MIRI MRS spectrum of IRAS 23385+6053 shows a plethora of interesting features. While the general spectrum is typical for an embedded protostar, we see many atomic and molecular gas lines boosted by the higher spectral resolution and sensitivity compared to previous space missions. Furthermore, ice and dust absorption features are also present. Here, we focus on the continuum emission, outflow tracers such as the H2(0-? 0)S(7), [FeII](4F9/2-6D9/2), and [NeII](2P1/2-2P3/2) lines, and the potential accretion tracer Humphreys α H I(7-6). The short-wavelength MIRI data resolve two continuum sources, A and B; mid-infrared source A is associated with the main millimeter continuum peak. The combination of mid-infrared and millimeter data reveals a young cluster in the making. Combining the mid-infrared outflow tracers H2, [FeII], and [NeII] with millimeter SiO data reveals a complex interplay of at least three molecular outflows driven by protostars in the forming cluster. Furthermore, the Humphreys α line is detected at a 3-?4σ? level toward the mid-infrared sources A and B. One can roughly estimate both accretion luminosities and corresponding accretion rates to be between ∼2.6 × 10-6 and ∼0.9 × 10-4 Mo yr-1. This is discussed in the context of the observed outflow rates. Conclusions. The analysis of the MIRI MRS observations for this young high-mass star-forming region reveals connected outflow and accretion signatures, as well as the enormous potential of JWST to boost our understanding of the physical and chemical processes at play during star formation., Astronomy & Astrophysics, 673, ISSN:0004-6361, ISSN:1432-0746

Luminous infrared starbursts in the early Universe are thought to be the progenitors of massive quiescent galaxies identified at redshifts 2- 4. Using the Mid-IRfrared Instrument (MIRI) on board the James Webb Space Telescope (JWST), we present mid-infrared sub-arcsec imaging and spectroscopy of such a starburst: the slightly lensed hyper-luminous infrared system SPT0311-58 at z = 6.9. The MIRI IMager (MIRIM) and Medium Resolution Spectrometer (MRS) observations target the stellar (rest-frame 1.26 μm emission) structure and ionised (Paα and Hα) medium on kpc scales in the system. The MIRI observations are compared with existing ALMA far-infrared continuum and [C II]158μm imaging at a similar angular resolution. Even though the ALMA observations imply very high star formation rates (SFRs) in the eastern (E) and western (W) galaxies of the system, the Hα line is, strikingly, not detected in our MRS observations. This fact, together with the detection of the ionised gas phase in Paα, implies very high internal nebular extinction with lower limits (AV) of 4.2 (E) and 3.9 mag (W) as well as even larger values (5.6 (E) and 10.0 (W)) by spectral energy distribution (SED) fitting analysis. The extinction-corrected Paα lower limits of the SFRs are 383 and 230 M⊙ yr-1 for the E and W galaxies, respectively. This represents 50% of the SFRs derived from the [C II]158 μm line and infrared light for the E galaxy and as low as 6% for the W galaxy. The MIRIM observations reveal a clumpy stellar structure, with each clump having 3- 5× 109 M⊙ mass in stars, leading to a total stellar mass of 2.0 and 1.5× 1010 M⊙ for the E and W galaxies, respectively. The specific star formation (sSFR) in the stellar clumps ranges from 25 to 59 Gyr-1, assuming a star formation with a 50- 100 Myr constant rate. This sSFR is three to ten times larger than the values measured in galaxies of similar stellar mass at redshifts 6- 8. Thus, SPT0311-58 clearly stands out as a starburst system when compared with typical massive star-forming galaxies at similar high redshifts. The overall gas mass fraction is Mgas/M∗ ∼ 3, similar to that of z ∼ 4.5- 6 star-forming galaxies, suggesting a flattening of the gas mass fraction in massive starbursts up to redshift 7. The kinematics of the ionised gas in the E galaxy agrees with the known [C II] gas kinematics, indicating a physical association between the ionised gas and the cold ionised or neutral gas clumps. The situation in the W galaxy is more complex, as it appears to be a velocity offset by about +700 km s-1 in the Paα relative to the [C II] emitting gas. The nature of this offset and its reality are not fully established and require further investigation. The observed properties of SPT0311-58, such as the clumpy distribution at sub(kpc) scales and the very high average extinction, are similar to those observed in low- and intermediate-z luminous (E galaxy) and ultra-luminous (W galaxy) infrared galaxies, even though SPT0311-58 is observed only ∼800 Myr after the Big Bang. Such massive, heavily obscured clumpy starburst systems as SPT0311-58 likely represent the early phases in the formation of a massive high-redshift bulge, spheroids and/or luminous quasars. This study demonstrates that MIRI and JWST are, for the first time, able to explore the rest-frame near-infrared stellar and ionised gas structure of these galaxies, even during the Epoch of Reionization., Astronomy & Astrophysics, 671, ISSN:0004-6361, ISSN:1432-0746

Carbon is an essential element for life but how much can be delivered to young planets is still an open question. The chemical characterization of planet-forming disks is a crucial step in our understanding of the diversity and habitability of exoplanets. Very low-mass stars ($, version submitted to Nature Astronomy

Loss of FGF signaling leads to defects in salivary gland branching, but the mechanisms underlying this phenotype remain largely unknown. We disrupted expression of Fgfr1 and Fgfr2 in salivary gland epithelial cells and find that both receptors function coordinately in regulating branching. Strikingly, branching morphogenesis in double knockouts is restored by Fgfr1/2 knockin alleles incapable of engaging canonical RTK signaling, suggesting that additional FGF dependent mechanisms play a role during salivary gland branching. Fgfr1/2 conditional null mutants showed defective cell-cell and cell-matrix adhesion, both of which have been shown to play instructive roles in salivary gland branching. Loss of FGF signaling led to disordered cellbasement membrane interactions in vivo as well as in organ culture. This was partially restored upon introducing Fgfr1/2 wild type or signaling alleles incapable of eliciting canonical intracellular signaling. Together, our results identify non-canonical FGF signaling mechanisms that regulate branching morphogenesis through cell adhesion processes.

The West Carney Hunton Field (WCHF) is an important oil field in central Oklahoma. Deposited during a series of sea-level rises and falls on a shallow shelf, the Cochrane and Clarita Formations (Hunton Group) have undergone a complex series of diagenetic events. The Hunton section of the WCHF comprises dolomitized crinoidal packstones, brachiopod “reefs” and grainstones, thin intervals of fine-grained crinoidal wackestones, and infrequent mudstones that were diagenetically affected by repeated sea-level change. Widespread karst is evidenced by multiple generations of solution-enlarged fractures, vugs, and breccias, which extend through the entire thickness of the Hunton. Karst development likely occurred during sea-level lowstands. Partial to complete dolomitization of Hunton limestones is interpreted to have occurred as a result of convective circulation of normal seawater during sea-level highstands. Open-space-filling calcite cements postdate dolomitization and predate deposition of the overlying siliciclastic section, which comprises the Misener Sandstone and Woodford Shale. Petrographic evaluation and carbon and oxygen isotope values of the calcite cements suggest precipitation by Silurian seawater and mixed seawater and meteoric water. Carbon and oxygen isotopic signatures of dolomite may have been partially reset by dedolomitization that was concurrent with calcite cementation. Fluid inclusions in late diagenetic celestite crystals observed in the Clarita Formation indicate that the WCHF was invaded by saline basinal fluids and petroleum after burial, during later stages of diagenesis. The timing of late diagenetic fluid flow and petroleum generation likely was during the Ouachita orogeny, which was occurring to the south. There is no evidence that late diagenetic fluids significantly altered the dolomite reservoir that formed earlier. The WCHF provides an ancient example of early diagenetic dolomitization by seawater that remains relatively unaltered by later diagenetic events.

Coupling quantum emitters and nanostructures, in particular cold atoms and waveguides, has recently raised a large interest due to unprecedented possibilities of engineering light-matter interactions. However, the implementation of these promising concepts has been hampered by various theoretical and experimental issues. In this work, we propose a new type of periodic dielectric waveguide that provides strong interactions between atoms and guided photons with an unusual dispersion. We design an asymmetric comb waveguide that supports a slow mode with a quartic (instead of quadratic) dispersion and an electric field that extends far into the air cladding for an optimal interaction with atoms. We compute the optical trapping potential formed with two guided modes at frequencies detuned from the atomic transition. We show that cold Rubidium atoms can be trapped as close as 100 nm from the structure in a 1.3-mK-deep potential well. For atoms trapped at this position, the emission into guided photons is largely favored, with a beta factor as high as 0.88 and a radiative decay rate into the slow mode 10 times larger than the free-space decay rate., Comment: 14 pages, 6 figures

Fibre laser spot (circular) welds (LSW) in dual phase DP780 steel grade were produced with fusion areas equivalent to conventional resistance spot welds (RSW) using different fibre laser parameters. Shear tensile properties show significantly higher loads in fibre laser spot welds primarily because of the combined strength of spot size, and hard microstructures in the fusion zone and heat-affected zone (HAZ). Greater HAZ softening is observed at high heat inputs. The transition of failure mode from interfacial to pull-out and the corresponding strength value is primarily controlled by the weld size. The crack initiation site and propagation mechanism were observed to be different for interfacial and pull-out failure. The increased HAZ softening with increase heat input was quantified with nano-indentation hardness measurement technique.

Material testing for plasma facing components (PFCs) in future fusion devices reveals important damage mechanisms that impact lifetime and performance. During operation, PFCs in the divertor region will be subjected to high particle fluxes and heat loads. Tungsten (W) is currently the leading candidate material for divertor PFCs, due to its high melting point, high thermal conductivity, and low tritium retention. Laboratory experiments have effectively characterized mechanisms of damage on W due to different forms of radiation. However, understanding how different species of incident plasma particles interact with one another to affect the resultant strength of the material remains in development. In this study, W samples were exposed to simultaneous ELM-like heat loading and high-flux He+ and D+ ion irradiation at different ELM intensities to further elucidate the complex synergistic effects inherent in a fusion environment. ELM-like heat loading was replicated using a 1064 nm Nd:YAG pulsed millisecond laser at different energy densities. Exposures produced a shale-like microstructure with or without concurrent He+ and D+ ion irradiation. However, adding D+ to a simultaneous laser + He+ irradiation reduced pore formation and inhibited early-stage nanostructure formation. Changes in surface morphology with the addition of D+ could be attributed to super-saturation in the near-surface layer. While the addition of He+ and D+ clearly increased W erosion, the laser energy density did not have as clear of an effect. Increasing the ELM intensity reduced the number of pores, but increased the pore size. Future studies need to explore whether near-surface D impacts pore formation and total He desorption. Continued research on the combined effect of high-flux particle irradiation and transient heat loading will help refine predictions of material performance for ITER and beyond.

The variety of poststroke impairments and compensatory mechanisms necessitate adaptive and subject-specific approaches to locomotor rehabilitation. To implement subject-specific, adaptive training to treadmill-based gait training, we developed a user-driven treadmill (UDTM) control algorithm that adjusts the user’s speed in real-time. This study examines the response of individuals poststroke to the combination of UDTM control and electrical stimulation of the paretic ankle musculature to augment forward propulsion during walking. Sixteen individuals poststroke performed a randomized series of walking tasks on an instrumented split-belt treadmill at their self-selected speeds 1) with fixed speed treadmill (FSTM) control only, 2) FSTM control and paretic limb functional electrical stimulation (FES), 3) UDTM control only, and 4) UDTM control and FES. With UDTM control and FES, participants selected speeds that were 0.13 m/s faster than their speeds with fixed speed control only. This instantaneous increase is comparable to the gains in SS speed seen after 12 weeks of training with FES and fast walking with fixed speed treadmill control by Kesar and colleagues (Δ = 0.18 m/s). However, we saw no significant differences in the corresponding push-off forces or trailing limb position. Since individuals can use a variety of strategies to change their walking speeds, it is likely that the differences among individual responses obscured trends in the group average changes in mechanics. Ultimately, the combination of UDTM control and functional electrical stimulation (FES) allows individuals to increase speeds after a short exposure and may be a beneficial addition to poststroke gait training programs.

Financial constraints are one of the biggest barriers for women of low-income countries to receive necessary reproductive health services. Educating women about the importance of saving money has been incorporated as a component of antenatal care (ANC) contacts, but little is known whether ANC contacts influence women’s saving. A secondary analysis was conducted on data from a cross-sectional household survey study of 1109 women who recently gave birth in two rural districts of Zambia. Receiving ANC contacts early and often and discussing saving money during ANC were associated with saving money for the mother’s birth, but not with saving enough money for the most recent birth. Continued effort is needed to encourage women to attend ANC contacts earlier and more frequently. Additionally, the importance of saving money for birth should be discussed during ANC contacts. Future studies need to explore why women’s action in saving does not necessarily lead to saving enough for childbirth.

Financial constraints are one of the biggest barriers for women of low-income countries to receive necessary reproductive health services. Educating women about the importance of saving money has been incorporated as a component of antenatal care (ANC) contacts, but little is known whether ANC contacts influence women's saving.A secondary analysis was conducted on data from a cross-sectional household survey study of 1109 women who recently gave birth in two rural districts of Zambia.Receiving ANC contacts early and often and discussing saving money during ANC were associated with saving money for the mother's birth, but not with saving enough money for the most recent birth.Continued effort is needed to encourage women to attend ANC contacts earlier and more frequently. Additionally, the importance of saving money for birth should be discussed during ANC contacts. Future studies need to explore why women's action in saving does not necessarily lead to saving enough for childbirth.

Vegetable grafting has primarily been used in the commercial production of high-value crops in the Solanaceae and Cucurbitaceae families. In this study, we explored the feasibility of making a novel graft between pac choi (Brassica rapa L. var. chinensis) and daikon radish (Raphanus sativus L. var. longipinnatus) to create a plant with harvestable pac choi leafy vegetable above-ground, and a daikon radish taproot below-ground. ‘Mei Qing Choi’ pac choi (scion) was grafted onto ‘Bora King’ daikon radish (rootstock). Grafted pac choi–daikon radish plants did not show a decrease in SPAD value, canopy size, leaf number, leaf area, or above-ground weight compared with self-grafted pac choi plants. However, taproot formation was reduced in grafted pac choi–daikon radish plants, as shown by decreased taproot length, diameter, fresh weight, and dry weight compared with non- and self-grafted daikon radish plants. Surprisingly, grafting with radish increased the photosynthetic rate of the pac choi. This pilot study demonstrated the potential of creating a new pac choi–daikon radish vegetable product to help save growing space and minimize waste at consumption, as pac choi roots are not eaten and radish leaves are usually discarded. The inter-generic grafting between B. rapa var. chinensis and R. sativus var. longipinnatus could also provide a unique model system to help elucidate scion-rootstock synergy and above- and below-ground sink competition in horticultural crops.