Surprising impact of remote groups on the folding–unfolding and dimer-chain equilibria of bifunctional H-bonding unimers

Oligoamide 1, consisting of two H-bonding units linked by a trimethylene linker, was previously found to form a very stable, folded dimer. In this work, replacing the side chains and end groups of 1 led to derivatives that show the surprising impact of end groups on the folding and dimer-chain equilibria of the resultant molecules

Linear Convergence of Natural Policy Gradient Methods with Log-Linear Policies

We consider infinite-horizon discounted Markov decision processes and study the convergence rates of the natural policy gradient (NPG) and the Q-NPG methods with the log-linear policy class. Using the compatible function approximation framework, both methods with log-linear policies can be written as approximate versions of the policy mirror descent (PMD) method. We show that both methods attain linear convergence rates and $\mathcal{O}(1/\epsilon^2)$ sample complexities using a simple, non-adaptive geometrically increasing step size, without resorting to entropy or other strongly convex regularization. Lastly, as a byproduct, we obtain sublinear convergence rates for both methods with arbitrary constant step size

Correction: Surprising impact of remote groups on the folding–unfolding and dimer-chain equilibria of bifunctional H-bonding unimers

The authors regret that in the original article the spelling of one author’s surname is incorrect. The correct name of the author is ‘Shuang Chen’. The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers

Correction: Surprising impact of remote groups on the folding–unfolding and dimer-chain equilibria of bifunctional H-bonding unimers

The authors regret that in the original article the spelling of one author’s surname is incorrect. The correct name of the author is ‘Shuang Chen’. The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers

Intense duskside lower band chorus waves observed by Van Allen Probes: Generation and potential acceleration effect on radiation belt electrons

Abstract Local acceleration driven by whistler mode chorus waves largely accounts for the enhancement of radiation belt relativistic electron fluxes, whose favored region is usually considered to be the plasmatrough with magnetic local time approximately from midnight through dawn to noon. On 2 October 2013, the Van Allen Probes recorded a rarely reported event of intense duskside lower band chorus waves (with power spectral density up to 10-3nT 2/Hz) in the low-latitude region outside of L=5. Such chorus waves are found to be generated by the substorm-injected anisotropic suprathermal electrons and have a potentially strong acceleration effect on the radiation belt energetic electrons. This event study demonstrates the possibility of broader spatial regions with effective electron acceleration by chorus waves than previously expected. For such intense duskside chorus waves, the occurrence probability, the preferential excitation conditions, the time duration, and the accurate contribution to the long-term evolution of radiation belt electron fluxes may need further investigations in future

Availability of Food Preparation Supplies among Pregnant Women: Preliminary Results from the Decision Making, Eating, and Weight Gain during Pregnancy (DEW) Study

Background: Lack of cooking supplies may be a potential barrier to preparing healthy meals at home. We examined the availability of food preparation supplies among pregnant women in relation to sociodemographic characteristics. Methods: We used preliminary data (N=59) from an ongoing study which enrolled English-speaking women aged 18+ years, pregnant with singleton gestation \u3c36\u3eweeks, pre-pregnancy BMI 18.5-40 kg/m2, and planning to deliver at UMMHC. Women completed the Food Preparation Checklist (FPC) at home. The FPC asks women if 41 specific food preparation items; scores reflect number of items present in the home. Other variables were self-reported. Pearson’s correlation, t-tests, and ANOVAs provided comparisons. We constructed an adjusted linear regression model to explore FPC by sociodemographic characteristics. Results: Women were aged 30.3 (SD=4.1) years, 64.4% were non-Hispanic White, 84.8% were married or living with a partner, and 30.5% reported difficulty paying for basic expenses. Women were enrolled at 22.7 (SD=5.6) weeks gestation; 30.5% were primigravid. Mean pre-pregnancy BMI was 25.0 (SD=4.6) kg/m2; 25.4% were overweight and 17.0% obese. Average FPC score was 32.3 (SD=6.1; range:14-39). FPC scores were higher among Non-Hispanic White women (34.6±3.5 vs. 28.1±7.5, p\u3c0.0001), those with higher education (28.3±7.0 high school/GED or less, 31.0±6.2 some/college degree, vs. 34.7±4.6 some/degree graduate, p\u3c0.01), those married or living with a partner (33.3±5.7 vs. 26.9±5.7, p\u3c0.01), with lower pre-pregnancy BMI (r=-0.38, p\u3c0.01), and who had no difficulty paying for basic expenses (34.0±5.0 vs. 28.4±6.6, p\u3c0.001). In a model that additionally adjusted for pre-pregnancy BMI, non-Hispanic White women had on average 5.7 more food preparation items (95% CI: 3.2, 8.3) and those reporting difficulty paying for basic expenses 3.8 fewer items (95% CI: -6.8, -0.9). Conclusions: Understanding the food preparation supplies available to pregnant women may be useful when designing interventions to improve diet quality and promote healthy weight gain during pregnancy