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We report the first measurement of the parity-violating elastic electron scattering asymmetry on ^{27}Al. The ^{27}Al elastic asymmetry is A_{PV}=2.16±0.11(stat)±0.16(syst)  ppm, and was measured at ⟨Q^{2}⟩=0.02357±0.00010  GeV^{2}, ⟨θ_{lab}⟩=7.61°±0.02°, and ⟨E_{lab}⟩=1.157  GeV with the Q_{weak} apparatus at Jefferson Lab. Predictions using a simple Born approximation as well as more sophisticated distorted-wave calculations are in good agreement with this result. From this asymmetry the ^{27}Al neutron radius R_{n}=2.89±0.12  fm was determined using a many-models correlation technique. The corresponding neutron skin thickness R_{n}-R_{p}=-0.04±0.12  fm is small, as expected for a light nucleus with a neutron excess of only 1. This result thus serves as a successful benchmark for electroweak determinations of neutron radii on heavier nuclei. A tree-level approach was used to extract the ^{27}Al weak radius R_{w}=3.00±0.15  fm, and the weak skin thickness R_{wk}-R_{ch}=-0.04±0.15  fm. The weak form factor at this Q^{2} is F_{wk}=0.39±0.04.

Child-directed speech, as a specialized form of speech directed toward young children, has been found across numerous languages around the world and has been suggested as a universal feature of human experience. However, variation in its implementation and the extent to which it is culturally supported has called its universality into question. Child-directed speech has also been posited to be associated with expression of positive affect or "happy talk." Here, we examined Canadian English-speaking adults' ability to discriminate child-directed from adult-directed speech samples from two dissimilar language/cultural communities; an urban Farsi-speaking population, and a rural, horticulturalist Tseltal Mayan speaking community. We also examined the relationship between participants' addressee classification and ratings of positive affect. Naive raters could successfully classify CDS in Farsi, but only trained raters were successful with the Tseltal Mayan sample. Associations with some affective ratings were found for the Farsi samples, but not reliably for happy speech. These findings point to a complex relationship between perception of affect and CDS, and context-specific effects on the ability to classify CDS across languages., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Soderstrom, Casillas, Gornik, Bouchard, MacEwan, Shokrkon and Bunce.)

A beam-normal single-spin asymmetry generated in the scattering of transversely polarized electrons from unpolarized nucleons is an observable related to the imaginary part of the two-photon exchange process. We report a 2% precision measurement of the beam-normal single-spin asymmetry in elastic electron-proton scattering with a mean scattering angle of θ_{lab}=7.9° and a mean energy of 1.149 GeV. The asymmetry result is B_{n}=-5.194±0.067(stat)±0.082 (syst) ppm. This is the most precise measurement of this quantity available to date and therefore provides a stringent test of two-photon exchange models at far-forward scattering angles (θ_{lab}→0) where they should be most reliable.

Objective: This study aims to evaluate the comparative performance of a resorbable nanofiber wound matrix (Restrata Wound Matrix; Acera Surgical Inc, St Louis, MO) and a bilayered collagen xenograft (Integra Bilayer Matrix Wound Dressing; Integra, Plainsboro, NJ) in healing critical full-thickness cutaneous wounds in a preclinical porcine model., Materials and Methods: Full-thickness cutaneous wounds were created in Yucatan miniature swine and treated with either the nanofiber wound matrix or xenograft. Wound area was measured and inflammation and healing were assessed until euthanasia at day 15 or 30, at which time tissue samples were harvested for histopathology., Results: Wounds treated with the nanofiber wound matrix demonstrated significantly faster wound areal reduction, less inflammation, greater neovascularization, more collagen maturation, and superior quality of healing compared with wounds treated with the xenograft., Conclusions: The nanofiber wound matrix is an effective wound healing material that may offer a unique alternative in the treatment of challenging refractory wounds.

Wound matrix materials are used to improve the regeneration of dermal and epidermal layers in both acute and chronic wounds. Contemporary wound matrices are primarily composed of biologic materials such as processed xenogeneic and allogeneic tissues. Unfortunately, existing biologic wound matrices possess multiple limitations including poor longevity, durability, strength, and enzymatic resistance required for persistent support for new tissue formation. A fully-synthetic, resorbable electrospun material (Restrata Wound Matrix, Acera, St.Louis, Missouri ) that exhibits structural similarities to the native extracellular matrix offers a new approach to the treatment of acute and chronic wounds. This novel matrix is the first product to combine the advantages of synthetic construction (e.g. resistance to enzymatic degradation, excellent biocompatibility, strength/durability and controlled degradation) with the positive attributes of biologic materials (e.g. biomimetic architecture similar to human extracellular matrix (ECM), fibrous architecture optimized to support cellular migration and proliferation, engineered porosity to encourage tissue ingrowth and vascularization). These features allow RWM to achieve rapid and complete healing of full-thickness wounds that, in preclinical studies, is comparable to Integra Bilayer Wound Matrix (Integra LifeSciences, Plainsboro, New Jersey), a gold standard biologic material with diverse clinical indications in the wound care. Together, this review suggests that the RWM offers a unique fully-synthetic alternative to existing biologic matrices that is effective, widely available, easy to store, simple to apply and low cost., Competing Interests: Matthew MacEwan is the patent holder for the technology discussed in this review (Restrata Wound Matrix, Acera Surgical)

A fully synthetic electrospun matrix was compared to a bi-layered xenograft in the healing of full thickness cutaneous wounds in Yucatan miniature swine. Full thickness wounds were created along the dorsum, to which these matrices were applied. The wound area was measured over the course of healing and wound tissue was scored for evidence of inflammation and healing. Animals were sacrificed at Day 15 and Day 30 and tissue samples from the wound site were harvested for histopathological analysis to evaluate inflammation and tissue healing as evidenced by granulation tissue, collagen maturation, vascularization, and epithelialization. Average wound area was significantly smaller for treatment group wounds compared to control group wounds at 15 and 30 days ([7.7 cm 2 ± 0.9]/[3.8 cm 2 ± 0.8]) and ([2.9 cm 2 ± 1.1]/[0.2 cm 2 ± 0.0]) (control/treatment) (p = 0.002/p = 0.01). Histopathological analysis of wound sections revealed superior quality of healing with treatment group wounds, as measured by inflammatory response, granulation tissue, and re-epithelialization. A fully synthetic electrospun matrix was associated with faster rates of wound closure characterized by granulation tissue, deposition of mature collagen and vascularization at earlier time points than in wounds treated with a bi-layered xenograft. Treatment with this fully synthetic material may represent a new standard of care by facilitating full-thickness wound closure while eliminating the risks of inflammatory response and disease transmission associated with biologic modalities., Competing Interests: The Restrata matrix examined in this study is currently patent pending under US Application number 20130197663 A1.

The Q(weak) experiment has measured the parity-violating asymmetry in ep elastic scattering at Q(2)=0.025(GeV/c)(2), employing 145 μA of 89% longitudinally polarized electrons on a 34.4 cm long liquid hydrogen target at Jefferson Lab. The results of the experiment's commissioning run, constituting approximately 4% of the data collected in the experiment, are reported here. From these initial results, the measured asymmetry is A(ep)=-279±35 (stat) ± 31 (syst) ppb, which is the smallest and most precise asymmetry ever measured in ep scattering. The small Q(2) of this experiment has made possible the first determination of the weak charge of the proton Q(W)(p) by incorporating earlier parity-violating electron scattering (PVES) data at higher Q(2) to constrain hadronic corrections. The value of Q(W)(p) obtained in this way is Q(W)(p)(PVES)=0.064±0.012, which is in good agreement with the standard model prediction of Q(W)(p)(SM)=0.0710±0.0007. When this result is further combined with the Cs atomic parity violation (APV) measurement, significant constraints on the weak charges of the up and down quarks can also be extracted. That PVES+APV analysis reveals the neutron's weak charge to be Q(W)(n)(PVES+APV)=-0.975±0.010.

Objective: To determine whether aspirin and antioxidant therapy, combined or alone, are more effective than placebo in reducing the development of cardiovascular events in patients with diabetes mellitus and asymptomatic peripheral arterial disease., Design: Multicentre, randomised, double blind, 2x2 factorial, placebo controlled trial., Setting: 16 hospital centres in Scotland, supported by 188 primary care groups., Participants: 1276 adults aged 40 or more with type 1 or type 2 diabetes and an ankle brachial pressure index of 0.99 or less but no symptomatic cardiovascular disease., Interventions: Daily, 100 mg aspirin tablet plus antioxidant capsule (n=320), aspirin tablet plus placebo capsule (n=318), placebo tablet plus antioxidant capsule (n=320), or placebo tablet plus placebo capsule (n=318)., Main Outcome Measures: Two hierarchical composite primary end points of death from coronary heart disease or stroke, non-fatal myocardial infarction or stroke, or amputation above the ankle for critical limb ischaemia; and death from coronary heart disease or stroke., Results: No evidence was found of any interaction between aspirin and antioxidant. Overall, 116 of 638 primary events occurred in the aspirin groups compared with 117 of 638 in the no aspirin groups (18.2% v 18.3%): hazard ratio 0.98 (95% confidence interval 0.76 to 1.26). Forty three deaths from coronary heart disease or stroke occurred in the aspirin groups compared with 35 in the no aspirin groups (6.7% v 5.5%): 1.23 (0.79 to 1.93). Among the antioxidant groups 117 of 640 (18.3%) primary events occurred compared with 116 of 636 (18.2%) in the no antioxidant groups (1.03, 0.79 to 1.33). Forty two (6.6%) deaths from coronary heart disease or stroke occurred in the antioxidant groups compared with 36 (5.7%) in the no antioxidant groups (1.21, 0.78 to 1.89)., Conclusion: This trial does not provide evidence to support the use of aspirin or antioxidants in primary prevention of cardiovascular events and mortality in the population with diabetes studied., Trial Registration: Current Controlled Trials ISRCTN53295293.