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Multicomponent interpenetrating polymer network (mIPN) hydrogels are promising tissue-engineering scaffolds that could closely resemble key characteristics of native tissues. The mechanical and biochemical properties of mIPNs can be finely controlled to mimic key features of target cellular microenvironments, regulating cell-matrix interactions. In this work, we fabricated hydrogels made of collagen type I (Col I), fibrin, hyaluronic acid (HA), and poly (ethylene glycol) diacrylate (PEGDA) using a network-by-network fabrication approach. With these mIPNs, we aimed to develop a biomaterial platform that supports the in vitro culture of human astrocytes and potentially serves to assess the effects of the abnormal deposition of fibrin in cortex tissue and simulate key aspects in the progression of neuroinflammation typically found in human pathologies such as Alzheimer’s disease (AD), Parkinson’s disease (PD), and tissue trauma. Our resulting hydrogels closely resembled the complex modulus of AD human brain cortex tissue (~7.35 kPa), promoting cell spreading while allowing for the modulation of fibrin and hyaluronic acid levels. The individual networks and their microarchitecture were evaluated using confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Human astrocytes were encapsulated in mIPNs, and negligible cytotoxicity was observed 24 h after the cell encapsulation. 

There is considerable interest in MnOH x moieties, particularly in the stepwise changes in those O–H bonds in tandem with Mn oxidation state changes. The reactivity of aquo-derived ligands, {MOH x }, is also heavily influenced by the electronic character of the other ligands. Despite the prevalence of oxygen coordination in biological systems, preparation of mononuclear Mn complexes of this type with all O-donors is rare. Herein, we report several Mn complexes with perfluoropinacolate (pin F ) 2− including the first example of a crystallographically characterized mononuclear {Mn( iii )OH} with all O-donors, K 2 [Mn(OH)(pin F ) 2 ], 3. Complex 3 is prepared via deprotonation of K[Mn(OH 2 )(pin F ) 2 ], 1, the p K a of which is estimated to be 18.3 ± 0.3. Cyclic voltammetry reveals quasi-reversible redox behavior for both 1 and 3 with an unusually large Δ E p , assigned to the Mn( iii / ii ) couple. Using the Bordwell method, the bond dissociation free energy (BDFE) of the O–H bond in {Mn( ii )–OH 2 } is estimated to be 67–70 kcal mol −1 . Complex 3 abstracts H-atoms from 1,2-diphenylhydrazine, 2,4,6-TTBP, and TEMPOH, the latter of which supports a PCET mechanism. Under basic conditions in air, the synthesis of 1 results in K 2 [Mn(OAc)(pin F ) 2 ], 2, proposed to result from the oxidation of Et 2 O to EtOAc by a reactive Mn species, followed by ester hydrolysis. Complex 3 alone does not react with Et 2 O, but addition of O 2 at low temperature effects the formation of a new chromophore proposed to be a Mn( iv ) species. The related complexes K(18C6)[Mn( iii )(pin F ) 2 ], 4, and (Me 4 N) 2 [Mn( ii )(pin F ) 2 ], 5, have also been prepared and their properties discussed in relation to complexes 1–3. 

Using data from 15 countries, this article investigates whether descriptive and prescriptive gender norms concerning housework and child care (domestic work) changed after the onset of the COVID-19 pandemic. Results of a total of 8,343 participants ( M = 19.95, SD = 1.68) from two comparable student samples suggest that descriptive norms about unpaid domestic work have been affected by the pandemic, with individuals seeing mothers’ relative to fathers’ share of housework and child care as even larger. Moderation analyses revealed that the effect of the pandemic on descriptive norms about child care decreased with countries’ increasing levels of gender equality; countries with stronger gender inequality showed a larger difference between pre- and post-pandemic. This study documents a shift in descriptive norms and discusses implications for gender equality—emphasizing the importance of addressing the additional challenges that mothers face during health-related crises. 

Oxidation of distorted square-planar perfluoropinacolate Co compound [Co II (pin F ) 2 ] 2− , 1 , to [Co III (pin F ) 2 ] 1− , 2 , is reported. Rigidly square-planar 2 has an intermediate-spin, S = 1, ground state and very large zero-field splitting (ZFS) with D = 67.2 cm −1 ; | E | = 18.0 cm −1 , ( E / D = 0.27), g ⊥ = 2.10, g ‖ = 2.25 and χ TIP = 1950 × 10 −6 cm 3 mol −1 . This Co( iii ) species, 2 , reacts with ROS to oxidise two (pin F ) 2− ligands to form tetrahedral [Co II (Hpfa) 4 ] 2− , 3 . 

Despite global commitments and efforts, a gender‐based division of paid and unpaid work persists. To identify how psychological factors, national policies, and the broader sociocultural context contribute to this inequality, we assessed parental‐leave intentions in young adults (18–30 years old) planning to have children (N = 13,942; 8,880 identified as women; 5,062 identified as men) across 37 countries that varied in parental‐leave policies and societal gender equality. In all countries, women intended to take longer leave than men. National parental‐leave policies and women's political representation partially explained cross‐national variations in the gender gap. Gender gaps in leave intentions were paradoxically larger in countries with more gender‐egalitarian parental‐leave policies (i.e., longer leave available to both fathers and mothers). Interestingly, this cross‐national variation in the gender gap was driven by cross‐national variations in women's (rather than men's) leave intentions. Financially generous leave and gender‐egalitarian policies (linked to men's higher uptake in prior research) were not associated with leave intentions in men. Rather, men's leave intentions were related to their individual gender attitudes. Leave intentions were inversely related to career ambitions. The potential for existing policies to foster gender equality in paid and unpaid work is discussed.