Favorable Transition Research Articles

Synthesis, spectroscopy, band gap energy and electrical conductivity of poly(dopamine–co–aniline) copolymer

Copolymerization is used to improve the solubility and processability of polymers and copolymers includes the individual properties of homopolymer. In this study, the poly(dopamine-co-aniline) (poly(DA-co-ANI) copolymer was synthesized and the UV–vis. absorption, optical band gap energy, fluorescence, FT-IR, SEM-EDS, MALDI-TOF-MS, XRD and electrical conductivity have been investigated. The obtained results for the poly(DA-co-ANI) copolymer were compared with the PDA and PANI homopolymers. It was observed that the poly(DA-co-ANI copolymer is soluble easily in NMP and DMF solvents. The optical band gap energy of the poly(DA-co-ANI) copolymer film were calculated. as 1.00 eV with favorable indirect transition. The poly(DA-co-ANI) copolymer showed the FL emission maximum bands at 390 and 533 nm wavelengths. It was observed from the SEM images that the poly(DA-co-ANI) has 0–1500 nm crystalline rectangular particles prepared in acidic media and 0–600 nm amorphous particles prepared in basic media. The electrical conductivity of the poly(DA-co-ANI) was 1.35 × 10−6 S/cm. In the MALDI-TOF-MS measurements, the number-average molecular weight of the copolymer was found as 2628 Da with a distribution up to 5500 Da. The poly(DA-co-ANI) copolymer, soluble in NMP and DMF solvents and with a low optical band gap energy can be utilized as optical, fluorescent, and semi-conductive material in biomedical applications.

Improving Electrocatalytic Oxygen Evolution through Local Field Distortion in Mg/Fe Dual‐site Catalysts

AbstractTransition metal single atom electrocatalysts (SACs) with metal‐nitrogen‐carbon (M−N−C) configuration show great potential in oxygen evolution reaction (OER), whereby the spin‐dependent electrons must be allowed to transfer along reactants (OH−/H2O, singlet spin state) and products (O2, triplet spin state). Therefore, it is imperative to modulate the spin configuration in M−N−C to enhance the spin‐sensitive OER energetics, which however remains a significant challenge. Herein, we report a local field distortion induced intermediate to low spin transition by introducing a main‐group element (Mg) into the Fe−N−C architecture, and decode the underlying origin of the enhanced OER activity. We unveil that, the large ionic radii mismatch between Mg2+ and Fe2+ can cause a FeN4 in‐plane square local field deformation, which triggers a favorable spin transition of Fe2+ from intermediate (dxy2dxz2dyz1dz21, 2.96 μB) to low spin (dxy2dxz2dyz2, 0.95 μB), and consequently regulate the thermodyna‐mics of the elementary step with desired Gibbs free energies. The as‐obtained Mg/Fe dual‐site catalyst demonstrates a superior OER activity with an overpotential of 224 mV at 10 mA cm−2 and an electrolysis voltage of only 1.542 V at 10 mA cm−2 in the overall water splitting, which outperforms those of the state‐of‐the‐art transition metal SACs.

Improving Electrocatalytic Oxygen Evolution through Local Field Distortion in Mg/Fe Dual-site Catalysts.

Transition metal single atom electrocatalysts (SACs) with metal-nitrogen-carbon (M-N-C) configuration show great potential in oxygen evolution reaction (OER), whereby the spin-dependent electrons must be allowed to transfer along reactants (OH- /H2 O, singlet spin state) and products (O2 , triplet spin state). Therefore, it is imperative to modulate the spin configuration in M-N-C to enhance the spin-sensitive OER energetics, which however remains a significant challenge. Herein, we report a local field distortion induced intermediate to low spin transition by introducing a main-group element (Mg) into the Fe-N-C architecture, and decode the underlying origin of the enhanced OER activity. We unveil that, the large ionic radii mismatch between Mg2+ and Fe2+ can cause a FeN4 in-plane square local field deformation, which triggers a favorable spin transition of Fe2+ from intermediate (dxy 2 dxz 2 dyz 1 dz2 1 , 2.96 μB ) to low spin (dxy 2 dxz 2 dyz 2 , 0.95 μB ), and consequently regulate the thermodyna-mics of the elementary step with desired Gibbs free energies. The as-obtained Mg/Fe dual-site catalyst demonstrates a superior OER activity with an overpotential of 224 mV at 10 mA cm-2 and an electrolysis voltage of only 1.542 V at 10 mA cm-2 in the overall water splitting, which outperforms those of the state-of-the-art transition metal SACs.

Experimental assessment of utilizing copper tailings as alkali-activated materials and fine aggregates to prepare geopolymer composite

Globally, there is an increasing attention drawn by copper tailings (CT) due to the environmental problems caused by its tremendous storage volume and low recycling rate. With the purpose of promoting the sustainability and value-added utilization of CT, this study used CT powder with particle size ≤ 0.075 mm, granulated blast furnace slag (GBFS), and fly ash (FA) to prepare CT/FA-GBFS geopolymer paste composites. Also, 0.075–0.6 mm CT sand was also used as a replacement of natural fine aggregates. The effect of CT powders on the mechanical strength of the geopolymer paste was assessed, as well as the influence of CT sand on the mechanical strength and the heavy metal leaching behavior of CT-GBFS geopolymer mortar. The obtained results from the study demonstrate that CT powder exhibits partial participation in the geopolymerization reaction within an alkaline environment. Additionally, it manifests a filling effect when incorporated as micro powders. It is noteworthy that the compressive strength of the geopolymer paste improved by 18% and the flexural strength by 74% when the CT content reached 45%. Furthermore, in the context of CT-GBFS geopolymer mortar, the 20% replacement ratio of CT sand yields a more favorable interfacial transition zone (ITZ) between the geopolymer paste and the mixed sand. This improved ITZ improves the mechanical properties of the mortar by about 10% compared to other experimental groups. Finally, when CT were immobilized in the CT-GBFS geopolymer mortar, the leaching of heavy metals from copper tailings was significantly reduced, eliminating the impact of CT utilization on the environment.

Motivational affective training and personal growth of health technologists, role of tutors

Introduction: cuban health shows comparable indicators with those of developed countries, the comprehensive training of technologists, who respond to the needs of society, stands out. Continuing and raising these quality budgets is currently a challenge for the medical university, which faces a student who lacks personal and psychological tools to manage his favorable transit through the institution. Objective: to reflect on the need for motivational affective training in the university educational context for the personal growth of health technologists. Methodology: methods of the theoretical level were used: the analytical-synthetic and the historical-logical; that allowed the approach to the theoretical foundations that support the process of motivational affective training in the educational context for the sake of personal growth of students; as well as the compression of its components and dimensions with the adoption of postures. Results: the necessary articulation between the motivational affective and personal growth is recognized in comprehensive training, teachers must assume it as a planned, dynamic and multifactorial process, in such a way that their practice is effective and achieves personal and professional transformation. of students from the intra and extracurricular. Conclusions: the teacher must plan, guide and conduct the motivational affective training, as a component in the comprehensive training of health technologists for the sake of their personal growth, always based on the individual and collective needs of the students, considering the context in which it develops.

(Invited) Nanoscale Surface Coatings for High-Performance Nickel-Rich LiNixMnyCozO2 Cathodes Via Atomic Layer Deposition

Nickel (Ni)-rich LiNixMnyCozO2 (NMCs, x + y + z = 1, x ≥ 0.6) are among the most promising cathodes for next-generation lithium-ion batteries (LIBs) and beyond, ascribed to their high capacity and low cost. With increasing Ni contents, however, NMCs become more challenging for commercialization, due to a series of aggravated issues. In addressing these issues, surface coating has been remaining as a facile and effective strategy. In this regard, atomic layer deposition (ALD) has been recognized as a unique surface-coating technique in the past decade, featuring its unrivaled capability for uniform and conformal coatings.1-3 ALD also is to date the only technique that can perform on either prefabricated electrodes or electrode powders directly. In searching for new solutions to the issues of NMCs, recently we have conducted a series of studies on different coatings, including oxides and sulfides via ALD.4-8 Our studies revealed that Li-containing oxides are better than Li-free oxides, due to improved ionic conductivity. They both served multiple roles for protecting NMCs, including as a physical barrier to mitigate undesirable interfacial reactions, a structural stabilizer to inhibit unfavorable phase transformation, and a robust network to improve mechanical integrity. Very interestingly, we for the first time have discovered that, compared to oxide coatings, sulfides are more advantageous. Our studies have revealed that, while acting similar roles as oxides, sulfides have some unusual protection effects for better performance of NMCs. We found that sulfides could experience some favorable phase transition during charge-discharge processes, which transferred sulfides into sulfites or/and sulfates. This transition process could particularly remove the released oxygen from NMCs and thereby protected electrolytes from oxidation. We further demonstrated that this transition is significant for achieving long-term stable cyclability of NMCs. Thus, our studies have greatly widened the search of surface coatings and provided new solutions for next-generation LIBs and beyond.

Global patterns of cancer transitions: A modelling study.

Cancer is a major contributor to global disease burden. Many countries experienced or are experiencing the transition that non-infection-related cancers replace infection-related cancers. We aimed to characterise burden changes for major types of cancers and identify global transition patterns. We focused on 10 most common cancers worldwide and extracted age-standardised incidence and mortality in 204 countries and territories from 1990 to 2019 through the Global Burden of Disease Study. Two-stage modelling design was used. First, we applied growth mixture models (GMMs) to identify distinct trajectories for incidence and mortality of each cancer type. Next, we performed latent class analysis to detect cancer transition patterns based on the categorisation results from GMMs. Kruskal-Wallis H tests were conducted to evaluate associations between transition patterns and socioeconomic indicators. Three distinct patterns were identified as unfavourable, intermediate and favourable stages. Trajectories of lung and breast cancers had the strongest association with transition patterns among men and women. The unfavourable stage was characterised by rapid increases in lung, breast and colorectal cancers alongside stable or decreasing burden of gastric, cervical, oesophageal and liver cancers. In contrast, the favourable stage exhibited rapid declines in most cancers. The unfavourable stage was associated with lower sociodemographic index, health expenditure, gross domestic product per capita and higher maternal mortality ratio (P < .001 for all associations). Our findings suggest that unfavourable, intermediate and favourable transition patterns exist. Countries and territories in the unfavourable stage tend to be socioeconomically disadvantaged, and tailored intervention strategies are needed in these resource-limited settings.

Influence of biomass burning on ozone levels in the Megalopolis of Central Mexico during the COVID-19 lockdown

The massive reductions in anthropogenic emissions resulting from the COVID-19 lockdown provided a unique opportunity to evaluate the effect of mitigation measures aiming to abate air pollution. In Mexico, the total lockdown period took place during the dry-hot season when biomass burning activity is enhanced. Here, we investigate the role of biomass burning emissions on regional ozone levels in the Megalopolis of Central Mexico. The studied period covers the lockdown phases 2 and 3, and the first month of the New Normal.We applied a factor separation technique and process analysis to estimate the pure and synergistic contributions of emission reductions under lockdown and that from biomass burning to daily ozone maximum concentrations in 7 metropolitan areas of different states in the Megalopolis. The results revealed that biomass burning plumes likely masked the effect of massive reductions from mobile emissions, impacted the PBL development during phase 3 and favored transition and mixed NOx-limited and VOC-limited regional regimes. This contributed to increased ozone production in the middle to lower PBL by changing the regional background levels which potentially could bias high ozone production efficiency estimations.Given the Megalopolis contribution to economic and societal development at national scale, our study suggests that ozone mitigation measures during the dry-hot season targeting mainly mobile emissions will likely be offset by biomass burning plumes. A regional and synergic policy aiming to control biomass burning would help to reduce the occurrence of high ozone levels in Central Mexico with the co-benefit of tackling short-lived climate pollutants.

Monodispersed Transition Metals Induced Ordinary-Pressure Phase Transformation from Graphite to Diamond: A First-Principles Calculation

High pressure and high temperature are normally required for the transformation of graphite to diamond; thus, finding a method that allows the transformation to occur under ordinary pressure will be extremely promising for diamond synthesis. Here, it is found that graphite spontaneously transforms into diamond without any pressure by adding monodispersed transition metals, and the universal rules that will help predict the role of certain elements in the phase transition were studied. The results show that the favorable transition metals possess an atomic radius of 0.136–0.160 nm and an unfilled d-orbital of d2s2–d7s2, which allow more charge transfer and accumulation at the proper position between the metal and dangling C atoms, leading to stronger metal–C bonds and a lower energy barrier for the transition. This provides a universal method to prepare diamond from graphite under ordinary pressure and also provides a way for the synthesis from sp2 to sp3 bonded materials.

The "Non-Treated" Versus "LT3-Treated" Protocols of Short-Term Hypothyroidism Induction in Differentiated Thyroid Cancer: An Analysis of Hypothyroid Complications, Mood Disorders, and Quality of Life.

This study aimed to compare "non-treated" versus "levotriiodothyronine (LT3)-treated" protocols of short-term hypothyroidism induction prior to radioactive iodine (RAI) ablation therapy in differentiated thyroid cancer (DTC). A total of 120 DTC patients who had thyroxine withdrawal either via 4-week hypothyroidism induction (non-treated group, n=60) or 2-week administration and then 2-week withdrawal of LT3 (LT3-treated group, n=60) to induce hypothyroid state prior to RAI ablation after initial surgery were included. Complications related to hypothyroidism-induction, Beck Depression Inventory (BDI), Hospital Anxiety-Depression Scale (HADS), and SF-36 health-related quality of life (HRQoL) scores were recorded. In the non-treated group, transition from euthyroid to hypothyroid state was associated with significant increase in the likelihood of moderate-to-severe depression on BDI (p<0.001), presence of depression on HADS-D (p<0.001), presence of anxiety on HADS-A (6.7% during euthyroid state vs. 33.3% during hypothyroid state, p<0.001), and major syndrome on BPRS (0.0 vs. 10.0%, p=0.001) as well as significant decrease in all SF-36 HRQoL domain scores (p<0.001 for each). In conclusion, our findings indicate the likelihood of L3-treatment to enable a more favorable transition period from euthyroid to hypothyroid state without experiencing a deterioration in depression, anxiety, or HRQoL.

Catalyst-Substrate Helical Character Matching Determines the Enantioselectivity in the Ishihara-Type Iodoarenes Catalyzed Asymmetric Kita-Dearomative Spirolactonization.

Catalyst design has traditionally focused on rigid structural elements to prevent conformational flexibility. Ishihara's elegant design of conformationally flexible C2-symmetric iodoarenes, a new class of privileged organocatalysts, for the catalytic asymmetric dearomatization (CADA) of naphthols is a notable exception. Despite the widespread use of the Ishihara catalysts for CADAs, the reaction mechanism remains the subject of debate, and the mode of asymmetric induction has not been well established. Here, we report an in-depth computational investigation of three possible mechanisms in the literature. Our results, however, reveal that this reaction is best rationalized by a fourth mechanism called "proton-transfer-coupled-dearomatization (PTCD)", which is predicted to be strongly favored over other competing pathways. The PTCD mechanism is consistent with a control experiment and further validated by applying it to rationalize the enantioselectivities. Oxidation of the flexible I(I) catalyst to catalytic active I(III) species induces a defined C2-symmetric helical chiral environment with a delicate balance between flexibility and rigidity. A match/mismatch effect between the active catalyst and the substrate's helical shape in the dearomatization transition states was observed. The helical shape match allows the active catalyst to adapt its conformation to maximize attractive noncovalent interactions, including I(III)···O halogen bond, N-H···O hydrogen bond, and π···π stacking, to stabilize the favored transition state. A stereochemical model capable of rationalizing the effect of catalyst structural variation on the enantioselectivities is developed. The present study enriches our understanding of how flexible catalysts achieve high stereoinduction and may serve as an inspiration for the future exploration of conformational flexibility for new catalyst designs.

Atroposelective desymmetrization of 2-arylresorcinols via Tsuji-Trost allylation

Palladium-catalyzed asymmetric allylic alkylation has proven to be a powerful method for the preparation of a wide variety of chiral molecules. However, the catalytic and atroposelective allylic alkylation is still rare and challenging, especially for biaryl substrates. Herein, we report the palladium-catalyzed desymmetric and atroposelective allylation, in which the palladium complex with a chiral phosphoramidite ligand enables desymmetrization of nucleophilic 2-arylresorcinols in a highly enantioselective manner. With the aid of the secondary kinetic resolution effect, a wide variety of substrates containing a hydroxymethyl group at the bottom aromatic ring are able to provide O-allylated products up to 98:2 er. Computational studies show an accessible quadrant of the allylpalladium complex and provide three plausible transition states with intra- or intermolecular hydrogen bonding. The energetically favorable transition state is in good agreement with the observed enantioselectivity and suggests that the catalytic reaction would proceed with an intramolecular hydrogen bond.

Enhancement of surimi gel properties through the synergetic effect of fucoidan and oligochitosan

For the first time, two common marine-derived dietary fibres (MDFs), fucoidan (FU) and oligochitosan (OCS), were introduced as textural and nutritional enhancers in hairtail surimi gels. The MDFs could assist with inhabiting the endogenous proteolytic enzyme activity, unfolding the myosin to expose more reactive domains, inducing favorable protein conformational transition, and thus, promoting gelation. The highly hydrophilic MDFs rich in –OH groups can bind water molecules via strong hydrogen bonds, facilitating water redistribution within the gel network. Driven by the enhanced chemical forces, a stable protein-FU-OCS gel is obtained, which improves the hardness by almost 100% and the water holding capacity from 86.25% to 92.25%. Collectively, this study demonstrates that MDFs are a group of effective additives to improve gel characteristics and nutritional profiles of surimi-based seafood products. The proposed MDF-protein interaction model would guide the application of MDFs as novel additives in the food industry.

Covalently Interlayer‐Confined Organic–Inorganic Heterostructures for Aqueous Potassium Ion Supercapacitors (Small 4/2023)

Aqueous Potassium Ion Supercapacitors A covalently interlayer-confined polyaniline–MoS2 hybrid with a dual charge storage mechanism is developed for supercapacitors. In the hybrid, confined polyaniline induces a favorable phase transition, facilitates cross-layer electron transfer, and decreases K+ diffusion barrier, thus enabling high electrochemical performance. More details can be found in article number 2204275 by Shude Liu, Seong Chan Jun, and co-workers.

Immune-modulation by 7, 8-diacetoxy-4-methylthiocoumarin in total body-irradiated mice: Implications for the mitigation of radiation-induced hematopoietic injury

AimsDevelopment of novel medical countermeasures (MCMs) against acute radiation syndrome (ARS) and the associated lethality involves protection from and/or mitigation of radiation-induced hematopoietic injury, a critical clinical component of ARS. We earlier identified the molecule 7,8-diacetoxy-4-methylthiocoumarin (DAMTC) as a potent mitigator of hematopoietic injury and mortality in C57BL/6 mice when administered 24 h following total body irradiation (TBI). In the present study, we investigated mechanisms and functional relevance of immune modulation by DAMTC during the mitigation of hematopoietic injury. Main methodsC57BL/6 mice were subjected to TBI doses of 3 and 7.6Gy; administered DAMTC intra-peritoneally 24 h post TBI. Isolation, characterization, intra-cellular cytokine analysis of myeloid cells from bone marrow and spleen accompanied by flow cytometric determination and characterization of B-lymphocytes, serum isolation from peripheral blood and cytokine analysis. Key findingsResults showed that DAMTC induced stimulation of pro-inflammatory myeloid subsets in the bone marrow and spleen of TBI mice. Further, it promoted a favorable transition from Th2 to Th1 immunity, triggered humoral immunity, and activated an intricately balanced inflammatory response that appear to contribute to immune-modulation. SignificanceThus, the present study shows that immune-modulation maybe one of the contributing factors for the mitigation of hematopoietic injury by DAMTC and underscores its efficacy as a potent mitigator of hematopoietic injury that merits to be developed further as a novel MCM to combat H-ARS.

The Arizona Radio Observatory 1 mm Spectral Survey of the Hypergiant Star NML Cygni (215–285 GHz)

A sensitive (1σ rms ≤ 3 mK; 2 MHz resolution) 1 mm spectral survey (214.5–285.5 GHz) of the envelope of the oxygen-rich supergiant star NML Cygni (NML Cyg) has been conducted using the 10 m Submillimeter Telescope of the Arizona Radio Observatory. These data represent the first spectral line survey of NML Cyg and are complementary to a previous 1 mm survey of the envelope of a similar hypergiant, VY Canis Majoris (VY CMa). The complete NML Cyg data set is presented here. In the survey, 104 emission lines were observed, arising from 17 different molecules and 4 unidentified features. Many of the observed features have complex line profiles, arising from asymmetric outflows characteristic of hypergiant stars. While most of the lines in the survey arise from SiO, SO, SO2, and SiS, CO had the strongest emission. Five other C-bearing species are identified in the survey (HCN, CN, HCO+, CS, and HNC), demonstrating an active carbon chemistry despite the O-rich environment. Moreover, NS was observed, but not NO, although favorable transitions of both molecules lie in the surveyed region. Sulfur chemistry appears to be prominent in NML Cyg and plays an important role in the collimated outflows. The refractory species observed, NaCl and AlO, have narrow emission lines, indicating that these molecules do not reach the terminal expansion velocity. NaCl and AlO likely condense into dust grains at r < 50 R *. From NaCl, the chlorine isotope ratio was determined to be 35Cl/37Cl = 3.85 ± 0.30.

Noncovalent Stabilization of Radical Intermediates in the Enantioselective Hydroamination of Alkenes with Sulfonamides.

Noncovalent interactions (NCIs) are critical elements of molecular recognition in a wide variety of chemical contexts. While NCIs have been studied extensively for closed-shell molecules and ions, very little is understood about the structures and properties of NCIs involving free radical intermediates. In this report, we describe a detailed mechanistic study of the enantioselective radical hydroamination of alkenes with sulfonamides and present evidence suggesting that the basis for asymmetric induction in this process arises from attractive NCIs between a neutral sulfonamidyl radical intermediate and a chiral phosphoric acid (CPA). We describe experimental, computational, and data science-based evidence that identifies the specific radical NCIs that form the basis for the enantioselectivity. Kinetic studies support that C-N bond formation determines the enantioselectivity. Density functional theory investigations revealed the importance of both strong H-bonding between the CPA and the N-centered radical and a network of aryl-based NCIs that serve to stabilize the favored diastereomeric transition state. The contributions of these specific aryl-based NCIs to the selectivity were further confirmed through multivariate linear regression analysis by comparing the measured enantioselectivity to computed descriptors. These results highlight the power of NCIs to enable high levels of enantioselectivity in reactions involving uncharged open-shell intermediates and expand our understanding of radical-molecule interactions.

Unusual Enantiodivergence in Chiral Brønsted Acid-Catalyzed Asymmetric Allylation with β-Alkenyl Allylic Boronates.

We report herein a rare example of enantiodivergent aldehyde addition with β-alkenyl allylic boronates via chiral Brønsted acid catalysis. 2,6-Di-9-anthracenyl-substituted chiral phosphoric acid-catalyzed asymmetric allylation using β-vinyl substituted allylic boronate gave alcohols with R absolute configuration. The sense of asymmetric induction of the catalyst in these reactions is opposite to those in prior reports. Moreover, in the presence of the same acid catalyst, the reactions with β-2-propenyl substituted allylic boronate generated homoallylic alcohol products with S absolute configuration. Unusual substrate-catalyst C-H⋅⋅⋅π interactions in the favoured reaction transition state were identified as the origins of observed enantiodivergence through DFT computational studies.

Unusual Enantiodivergence in Chiral Brønsted Acid‐Catalyzed Asymmetric Allylation with β‐Alkenyl Allylic Boronates

AbstractWe report herein a rare example of enantiodivergent aldehyde addition with β‐alkenyl allylic boronates via chiral Brønsted acid catalysis. 2,6‐Di‐9‐anthracenyl‐substituted chiral phosphoric acid‐catalyzed asymmetric allylation using β‐vinyl substituted allylic boronate gave alcohols with R absolute configuration. The sense of asymmetric induction of the catalyst in these reactions is opposite to those in prior reports. Moreover, in the presence of the same acid catalyst, the reactions with β‐2‐propenyl substituted allylic boronate generated homoallylic alcohol products with S absolute configuration. Unusual substrate‐catalyst C−H⋅⋅⋅π interactions in the favoured reaction transition state were identified as the origins of observed enantiodivergence through DFT computational studies.

Sleep Duration and Kindergarten Adjustment.

The current study examined longitudinal linkages between child sleep duration and children's socioemotional, learning engagement, executive functioning, and academic outcomes across the full kindergarten (K) year. A measurement-burst design was employed to examine 3 different measures of child sleep duration in 7-day bursts at pre-K (July-August), early K (late September), mid-K (late November), and late K (mid-to-late April), using wrist actigraphy. These measures included mean amounts of child sleep per 24-hour period across the full week, proportion of 24-hour periods per week that children slept 10 or more hours, and proportion of nighttime sleep periods per week that children slept 10 or more hours. Children's outcomes at early, mid-, and late K were provided by their K teachers blind to children's sleep histories, and by assessments administered by project staff. Among the 3 sleep measures examined, regularity of nighttime sleep in which children slept 10 or more hours per night, especially at pre-K, consistently predicted more favorable K outcomes in both socioemotional, learning engagement, and academic domains. Results suggested that establishing healthy nighttime sleep habits before K start was especially promotive of better K adjustment across the full K year. These findings were controlled for income-to-poverty threshold ratios, child health status, and number of missed school days. Efforts to promote a favorable transition to first-time schooling should pay particular attention to sleep hygiene and regularity of 10-plus hours of nightly child sleep established before the start of K.