Summary In high-dimensional model selection problems, penalized least-square approaches have been extensively used. This paper addresses the question of both robustness and efficiency of penalized model selection methods, and proposes a data-driven weighted linear combination of convex loss functions, together with weighted L1-penalty. It is completely data-adaptive and does not require prior knowledge of the error distribution. The weighted L1-penalty is used both to ensure the convexity of the penalty term and to ameliorate the bias caused by the L1-penalty. In the setting with dimensionality much larger than the sample size, we establish a strong oracle property of the proposed method that possesses both the model selection consistency and estimation efficiency for the true non-zero coefficients. As specific examples, we introduce a robust method of composite L1-L2, and optimal composite quantile method and evaluate their performance in both simulated and real data examples.

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The effective separation of photogenerated carriers plays a vital role in photocatalytic reactions. In addition to the intrinsic driving force of photocatalysis, an external field generating an enhancement effect can provide extra energy to the photocatalytic system, acting as an additional impetus to separate photogenerated charges and thus improving the overall catalytic efficiency. Under the favorable noncontact conditions, exploring the effect of the external field, different from pure photocatalysis or photoelectrocatalysis, could widen the applications of photocatalysis technology. In this review, four typical noncontact external fields (i.e., thermal, magnetic, microwave, and ultrasonic fields) and their coupling effects on photocatalysis are summarized. Specifically, the review focuses on the mechanism and characteristics of each external field’s synergistic effect and their coupling effects on the performance of the catalytic system. The charge separation driving forces provided by the noncontact external field and the traditional one are distinguished and defined for the first time. The challenges and future prospects of noncontact external-field-driven photocatalysis are discussed. We hope that this review will provide a reference for the research and development of external-field-assisted photocatalysis and give insights for the in-depth study of external-field-coupling-enhanced photocatalysis toward improvement of the catalytic efficiency.

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Analysis of amino acids in milk protein reveals a relatively low content of glycine. This study was conducted with young pigs to test the hypothesis that milk-fed neonates require dietary glycine supplementation for maximal growth. Fourteen-day-old piglets were allotted randomly into one of four treatments (15 piglets/treatment), representing supplementation with 0, 0.5, 1 or 2% glycine (dry matter basis) to a liquid milk replacer. Food was provided to piglets every 8 h (3 times/day) for 2 weeks. Milk intake (32.0-32.5 g dry matter/kg body weight per day) did not differ between control and glycine-supplemented piglets. Compared with control piglets, dietary supplementation with 0.5, 1 and 2% glycine increased (P < 0.05) plasma concentrations of glycine and serine, daily weight gain, and body weight without affecting body composition, while reducing plasma concentrations of ammonia, urea, and glutamine, in a dose-dependent manner. Dietary supplementation with 0.5, 1 and 2% glycine enhanced (P < 0.05) small-intestinal villus height, glycine transport (measured using Ussing chambers), mRNA levels for GLYT1, and anti-oxidative capacity (indicated by increased concentrations of reduced glutathione and a decreased ratio of oxidized glutathione to reduced glutathione). These novel results indicate, for the first time, that glycine is a nutritionally essential amino acid for maximal protein accretion in milk-fed piglets. The findings not only enhance understanding of protein nutrition, but also have important implications for designing improved formulas to feed human infants, particularly low birth weight and preterm infants.

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Background: Cannabinoid has long been used for medicinal purposes. Cannabinoid signaling has been considered the therapeutic target for treating pain, addiction, obesity, inflammation, and other diseases. Recent studies have suggested that in addition to CB1 and CB2, there are non-CB1 and non-CB2 cannabinoid-related orphan GPCRs including GPR18, GPR55, and GPR119. In addition, CB1 and CB2 display allosteric binding and biased signaling, revealing correlations between biased signaling and functional outcomes. Interestingly, new investigations have indicated that CB1 is functionally present within the mitochondria of striated and heart muscles directly regulating intramitochondrial signaling and respiration. Conclusion: In this review, we summarize the recent progress in cannabinoid-related orphan GPCRs, CB1/CB2 structure, Gi/Gs coupling, allosteric ligands and biased signaling, and mitochondria-localized CB1, and discuss the future promise of this research.