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关键词： Hydrogenation   Diastereoselectivity   1,3-Dipolar cycloaddition  

摘要： A practical and simple synthetic strategy for the synthesis of nitrones has been developed. Hydrogenation of 2-(2-nitro-1-phenylethyl)cyclohexanone by Pd/C afforded the corresponding nitrones in good to high yield and in high diastereoselectivity. The starting materials, 2-(2-nitro-1-phenylethyl)cyclohexanones, were easily prepared by the reaction of substituted cyclohexanones and nitroalkenes in the presence of 10 mol% of pyrrolidine.

关键词： self-management   social support   type 1 diabetes  

摘要： Aims Little is known about how different aspects of social relationships relate to diabetes self-management and glycaemic outcomes in young adults with type 1 diabetes (T1D). We examined relationships of general and diabetes-specific social variables with diabetes self-management and HbA1c. We hypothesized diabetes-specific factors would more strongly associate with self-management and HbA1c than general social *** We analysed baseline data from 100 young adults with T1D (Mage = 19.9 +/- 1.3 years) enrolled in a randomized controlled trial of a paediatric to adult care transition intervention. We examined associations of self-reported general and diabetes-specific social factors with self-reported self-management behaviours and HbA1c in 4 separate multiple regression models. Models controlled for demographic and medical variables with significant bivariate *** In the general social factor models, the only significant predictor of self-management behaviours was general emotional support (Beta = 0.208);there were no significant predictors associated with HbA1c. In the diabetes-specific social factor models, getting help with diabetes (Beta = 0.37) and pandemic-related diabetes support (Beta = -0.33) significantly predicted self-management behaviours and getting help with diabetes (Beta = -0.26) and diabetes disclosure/social support (Beta = 0.24) significantly predicted *** Diabetes-specific social support is important for medical and behavioural diabetes outcomes in young adults with T1D during this transitional period. Preparation for transfer may benefit from assisting young adults in seeking direct help with diabetes management from family and friends. More research is needed on how to help young adults acquire practical diabetes support to enhance clinical care.

关键词： attitude   dual process theory   health behaviour   implicit association test   measurement   smoking  

摘要： The study develops a novel method to measure System 1 (fast, cue-based, thought-light) smoking frequency as an outcome measure to overcome the limitations of existing measures. It also examines its relationship to System 2 (slow, deliberative) measures. 116 participants met in two sessions set at 48 hours apart. System 2 measure of smoking frequency was measured via self-reported 24-hour smoking frequency. System 1 smoking frequency was measured by observing the number of cigarettes participants carried and asking about the number of cigarette packs consumed between the two sessions. System 2 measure of smoking frequency underestimated System 1 smoking frequency by 47.4%. Results also revealed that System 1 smoking attitudes only predicted the newly developed System 1 smoking frequency significantly, while System 2 smoking attitudes predicted only System 2 smoking frequency significantly. Hence, interventions that modify explicit attitudes (System 2) might have a limited impact on observed (System 1) smoking behaviours.

关键词： Monge-Amp & egrave   re equation   Lipschitz change of variables   polynomially decaying densities  

摘要： In this paper we extend the scope of Caffarelli's contraction theorem, which provides a measure of the Lipschitz constant for optimal transport maps between log-concave probability densities in Rd. Our focus is on a broader category of densities, specifically those that are d1-concave and can be represented as V-d, where V is convex. By setting appropriate conditions, we derive linear or sublinear limitations for the optimal transport map. This leads us to a comprehensive Lipschitz estimate that aligns with the principles established in Caffarelli's theorem.

关键词： Colon cancer   Robotic surgery   Laparoscopic surgery   Right hemicolectomy   Randomised controlled trial   Comprehensive complication index  

摘要： BackgroundPrevious stage I-III colon cancer trials demonstrated improved peri-operative and similar long-term oncological outcomes with minimally invasive approaches compared with open surgery. Subsequent technical developments, including intracorporeal anastomosis, complete mesocolic excision (CME), refined pathologic grading systems and robotic approaches are increasingly used despite minimal supporting evidence. This international phase II trial aims to assess patient, surgical and pathological outcomes following robotic (RRHC) with laparoscopic right hemicolectomy (LRHC) for right sided colon ***, international multicentre pilot randomised phase II trial for patients with right colon adenocarcinoma, randomised 2:1 to robotic (RRHC) or laparoscopic (LRHC) surgery performed by accredited surgeons. Primary outcome was 90-day surgical morbidity measured using the Comprehensive Complication Index (CCI). Standardised pathology reviews, patient reported quality of life and surgeon task load index data was *** vs. LRHC surgery allocation was 19 vs. 10, mean operative time 3.8 vs. 3.1 h with no operative mortality, all had R0 resection, CME rate 53 vs. 50% and intact mesocolon 94 v 100%. CCI was significantly lower at 30 and 90 days after RRHC (median (Q1, Q3): 0 (0, 9) vs. 21 (21, 26);median difference: 21;95% CI 9-26;p = 0.005 at 30 days;p = 0.008 at 90 days). No significant differences in pathological nor quality of life data was observed. Surgeons task load data tended to favour robotic procedures. Median follow-up was 6 months. Limited funding led to early study *** improved short-term surgical morbidity and surgeon physical demand and performance whilst obtaining similar quality of life and pathological specimen quality compared to LRHC for right sided colon cancer, supporting the case for larger randomised *** registrationACTRN12620001378910

关键词： Beta-irradiation   Cellulose   Condensation reaction   EMIm acetate   Ionic liquids  

摘要： Biomass pretreatments often involve swelling in imidazolium-based ionic liquids (ILs) or beta-irradiation. The combination of both pretreatments can be used intentionally or can also occur inadvertently-for instance, upon irradiation of insufficiently washed biomass that still contains IL residues from an earlier pretreatment step. Previous work has shown a high reactivity of the reducing ends of cellulose upon irradiation in the presence of 1-ethyl-3-methyl-imidazolium (EMIm) ionic liquids which was now studied in detail by means of carbohydrate model compounds (monosaccharides, cellobiose, and cellodextrins). The model reactions show a selective loss of C-1 at the unprotected reducing end. This way, D-glucose is converted into D-arabinose, while D-galactose, the C-4-epimer of glucose, gives D-lyxose, the C-3 epimer of arabinose. The yield of the pentoses from the corresponding hexoses is proportional to the irradiation dose and reaches approx. 15% at an irradiation dose of 800 kGy. Also in cellobiose and cellodextrins, the terminal, reducing glucopyranose unit was converted into the lower arabino-homologue. In all of these processes, the removed C1-unit reacts as an umpoled formaldehyde synthon, confirmed by trapping in Stetter-type reactions with nitroethylene or *** mechanism of the fragmentation reaction is explained by the irradiative formation of the IL-derived N-heterocyclic carbene (NHC) which, as a strong nucleophile, reacts with the reducing ends of carbohydrates. The initially formed, well-known Breslow intermediate undergoes a retro-benzoin cleavage to give the lower homologue and the umpoled HCHO equivalent. By transfer of this IL-bound C1-synthon to suitable acceptors (trapping agents), the NHC can be regenerated so that a reaction cycle is completed and its action becomes catalytic. The structure elucidation of the products of the model compound reactions is presented, along with a discussion of the formation mechanisms.

关键词： 1/f noise   Transistors   Phase noise   Capacitance   Semiconductor device modeling   Circuits   Equivalent circuits   Integrated circuit modeling   Harmonic analysis   Perturbation methods   CMOS oscillators   phase noise   impulse sensitivity function  

摘要： Despite extensive research, the upconversion of 1/f noise into phase noise in harmonic oscillators is still an open topic of investigation. A few upconversion mechanisms are not fully understood yet. In particular, in class-B CMOS oscillators, the reason why a large tail capacitance combined with transistors entering the triode region for a portion of the oscillation cycle dramatically amplifies the 1/f noise upconversion has not been clearly pinpointed. This work introduces a simple yet powerful model to fully capture the 1/f noise upconversion mechanism. It shows that when the transistors enter the triode region, charge sharing between the tail capacitance and the tank capacitance injects a noise charge into the tank, generating phase noise perturbations quantified by the impulse sensitivity function. The analytical description results in closed-form equations that predict the $1/f<^>{3}$ phase noise sideband accurately, without relying on complex harmonic analysis or specific device nonlinearities. The excellent agreement with simulations performed both using idealized and real 55nm CMOS transistor models confirms the validity and robustness of the proposed framework, offering new insights and practical design guidelines for low phase noise CMOS oscillators.

关键词： Caogouzhimu decoction   Epilepsy   Ferroptosis   Hippocampal neurons   Intervention mechanism   Keap1-Nrf2-HO-1/GPX4 signal  

摘要： Background: The pathogenesis of epilepsy is closely associated with ferroptosis in hippocampal neurons. The Keap1-Nrf2-HO-1/GPX4 signaling pathway serves as a crucial endogenous antioxidant system and plays a significant role in regulating cellular ferroptosis. Caogouzhimu decoction has demonstrated potential antiepileptic effects in clinical practice, yet whether it intervenes in neuronal ferroptosis via this signaling pathway remains unclear. Objective: To explore the mechanism of the Keap1-Nrf2-HO-1/GPX4 signaling pathway in ferroptosis of hippocampal neurons in epilepsy and evaluate the intervention effect of Caogouzhimudecoction. Methods: Fifty mice were divided into a blank control group, a model control group and low-, medium- and high-dose Caogouzhimu decoction groups, with ten mice per group. The epilepsy model was induced by PTZ and the treatment groups received intragastric administration of Caogouzhimu decoction at doses of 40, 80 and 120 mg/mL, respectively. Behavior, hippocampal dentate gyrus neurogenesis and the expression levels of components related to the Keap1-Nrf2-HO-1/GPX4 signaling pathway were compared among the groups. Results: The high-dose group exhibited significantly shorter latency, reduced swimming distance and fewer convulsions above grade II compared to the other groups (P<0.05). Furthermore, the high-dose treatment effectively suppressed neurogenesis in the hippocampal dentate gyrus and the occurrence of ferroptosis, as evidenced by significantly lower mRNA expression levels of Keap1, Nrf2, HO-1 and GPX4 compared to those in the low- and medium-dose groups (P<0.05). Conclusion: Caogouzhimu decoction exerts anti-epileptic effects, likely by inhibiting hippocampal neuronal ferroptosis through modulation of the Keap1-Nrf2-HO-1/GPX4 signaling pathway. These findings provide a novel perspective for the clinical treatment of epilepsy.