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1.
Org Lett ; 2024 Jul 12.
Article in English | MEDLINE | ID: mdl-38994746

ABSTRACT

The reductive C-Si coupling of chlorosilanes offers efficient access to organosilanes, but its potential for constructing aliphatic ones remains largely unexplored. This manuscript presents a nickel-catalyzed Csp3-Si coupling reaction of unactivated alkyl-Br and R2Si(H)Cl. This work establishes a new approach for synthesizing highly functionalized aliphatic hydrosilanes from readily available chemical feedstocks. The reaction is easily scalable and can accommodate various functional groups, including carboxylic acids, which are usually incompatible with basic conditions.

2.
PLoS One ; 19(6): e0304707, 2024.
Article in English | MEDLINE | ID: mdl-38829882

ABSTRACT

BACKGROUND: Parental feeding practices (PFPs) play a key role in fostering preschoolers' dietary habits and in mitigating the risk of childhood obesity. Nevertheless, parents often employ inappropriate feeding practices, leading to children's potential nutrition-related issues. Thus, research is needed to inform interventions that focus on optimizing feeding practices. METHODS: This protocol describes the evaluation of a novel intervention-Empowering Parents to Optimize Feeding Practices (EPO-Feeding Program). The program will be evaluated with a two-arm feasibility randomized controlled trial (RCT) in Yangzhou, China. The program includes four weekly group-based training sessions led by healthcare professionals for parents of preschool children. The intervention incorporates sessions, group discussions, motivational interviewing, and supplementary materials (e.g., key messages and educational videos) aimed at enhancing parents' knowledge, skills, and behaviours related to feeding practices. The primary outcomes include i) implementation feasibility, primarily assessed through retention rates; and ii) program acceptability through a survey and qualitative process evaluation. Secondary outcomes encompass the potential impacts on i) PFPs, ii) parental perception of child weight (PPCW), iii) parenting sense of competence, iv) children's eating behaviours, and v) child weight status. Quantitative analyses include descriptive estimates for evaluating the feasibility and linear mixed regression analysis for testing the potential effects. Qualitative valuation will use thematic framework analysis. DISCUSSION: If this study shows this program to be feasible to implement and acceptable to parents, it will be used to inform a fully powered trial to determine its effectiveness. The research will also help inform policy and practices in the context of child nutrition promotion, particularly regarding implementing group-based training sessions by healthcare providers in similar settings. TRIAL REGISTRATION: Clinicaltrials.gov, Protocol #NCT06181773, 20/11/2023.


Subject(s)
Feasibility Studies , Feeding Behavior , Parents , Humans , Child, Preschool , Feeding Behavior/psychology , Parents/psychology , Female , Male , Parenting/psychology , Pediatric Obesity/prevention & control , China
3.
Obes Rev ; 25(4): e13688, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38186213

ABSTRACT

Caregivers' feeding practices are critical in shaping preschool children's eating habits and preventing childhood obesity. We conducted a systematic review and meta-analysis to evaluate the effectiveness of existing interventions targeting caregivers of preschool children, which aimed to promote child healthy eating and/or manage child weight and/or prevent child nutrition-related problems and included feeding practices as one of the outcomes. Eighteen studies with 18 intervention programs and 3887 respondents that completed baseline evaluations were eligible for data synthesis. Behavior change techniques (BCTs) frequently used included the following: instruction on how to perform the behavior and demonstration of the behavior. The pooled effects of randomized controlled trials (RCTs) on pressure to eat (pooled standardized mean difference [SMD] = 0.61; 95%CI: -1.16, -0.06), use of food as a reward (pooled SMD = -0.31; 95%CI: -0.61, -0.01), and emotional feeding (pooled SMD = -0.36; 95%CI: -0.66, -0.06) were found statistically significant compared with control groups at post-intervention. However, there were no pooled effects on restrictive feeding and pressure to eat at other follow-ups or on other feeding practices at post-intervention. Interventions may have short-term effects on decreasing the adoption of coercive control. Future interventions should directly and adequately optimize feeding practices, include components of individual support, and contribute to the maintenance of the effects over the long term.


Subject(s)
Fruit , Vegetables , Humans , Child, Preschool , Child , Caregivers , Feeding Behavior , Child Nutritional Physiological Phenomena
4.
J Am Chem Soc ; 145(24): 13008-13014, 2023 Jun 21.
Article in English | MEDLINE | ID: mdl-37285283

ABSTRACT

Transition-metal-catalyzed sila-cycloaddition has been a promising tool for accessing silacarbocycle derivatives, but the approach has been limited to a selection of well-defined sila-synthons. Herein, we demonstrate the potential of chlorosilanes, which are industrial feedstock chemicals, for this type of reaction under reductive nickel catalysis. This work extends the scope of reductive coupling from carbocycle to silacarbocycle synthesis and from single C-Si bond formation to sila-cycloaddition reactions. The reaction proceeds under mild conditions and shows good substrate scope and functionality tolerance, and it offers new access to silacyclopent-3-enes and spiro silacarbocycles. The optical properties of several spiro dithienosiloles as well as structural variations of the products are demonstrated.

5.
Appetite ; 180: 106343, 2023 01 01.
Article in English | MEDLINE | ID: mdl-36228780

ABSTRACT

BACKGROUND: The impacts of caregivers' perception of child weight on their non-responsive feeding practices are inconclusive. This systematic review aimed to examine their relationships. METHODS: A systematic search of five databases was conducted from inception to March 2022, following PRISMA guidelines. Data synthesis was performed using semi-quantitative approach and meta-analysis. RESULTS: Twenty-two studies with 12005 respondents were included for semi-quantitative analyses. Eighteen studies examined 26 associations between caregivers' perception of child weight and food restriction with 12 statistically significant associations being observed. A total of 22 relationships between caregivers' perception of child weight and pressure to eat were investigated, with 13 being statistically significant. The statistically significant associations consistently reported that caregivers' visual and self-reported perception of child weight was positively associated with their restrictive feeding and negatively associated with pressure to eat. The pooled odds ratios (ORs) indicated that caregivers who perceived their child as overweight were found to apply pressure to eat less frequently (OR = 0.61; 95%CI: 0.44, 0.84) compared with those who did not. However, caregivers' perception of child weight was not statistically significantly associated with restrictive feeding (OR = 1.37; 95%CI: 0.74, 2.55). CONCLUSION: Caregivers' self-reported and visual perception of child weight may be important risk factors for non-responsive feeding practices, particularly food restriction and pressure to eat. Thus, interventions need to consider the role of caregivers' perception of child weight, which may optimize feeding practices. Furthermore, longitudinal and intervention-based studies using validated measurements while controlling for potential covariates are needed to provide more evidence on their causal relationships.


Subject(s)
Research Design , Visual Perception , Child , Humans , Self Report
6.
Nutrients ; 16(1)2023 Dec 22.
Article in English | MEDLINE | ID: mdl-38201874

ABSTRACT

BACKGROUND: Child eating behaviors (CEBs) and parental feeding practices (PFPs) play critical roles in childhood obesity. However, the bidirectional relationships between CEBs and PFPs remain equivocal. This longitudinal study aimed to explore their bidirectional relationships. METHODS: A convenience sample of 870 parents with preschoolers was recruited in this longitudinal study (Shanghai, China). Three non-responsive feeding practices (NFPs), three responsive feeding practices (RFPs), five CEBs, and covariates were collected using validated questionnaires at baseline and the 6-month follow-up. Cross-lagged analyses using structural equation modeling (SEM) were performed to examine their bidirectional relationships. RESULTS: Eight hundred and fifty-three parents completed questionnaires, with a response rate of 98%. The mean age of their children at baseline was 4.39 years (standard deviation = 0.72 years). Eighteen out of sixty longitudinal cross-lagged paths were statistically significant. Parental encouragement of healthy eating and content-restricted feeding were found to be bidirectionally associated with child food fussiness. Four parent-driven associations and one child-driven association were identified between RFPs and CEBs. For example, monitoring was negatively associated with children's unhealthy eating habits (ß = -0.066, standard error (SE) = 0.025, p < 0.01). Eight child-driven associations and one parent-driven association were observed between NFPs and CEBs. For example, higher child satiety responsiveness predicted a higher pressure to eat (ß = 0.057, SE = 0.029, p < 0.01) and the use of food as a reward (ß = 0.083, SE = 0.031, p < 0.01). CONCLUSIONS: There were bidirectional, parent-driven, and child-driven associations. Parents should be encouraged to adopt RFPs to shape CEBs. Increasing parents' understanding of CEBs and providing them with reasonable coping strategies would help optimize PFPs.


Subject(s)
Fluorocarbons , Pediatric Obesity , Child , Humans , Child, Preschool , Longitudinal Studies , China , Pediatric Obesity/epidemiology , Pediatric Obesity/etiology , Feeding Behavior , Parents
7.
Nutrients ; 14(14)2022 Jul 14.
Article in English | MEDLINE | ID: mdl-35889843

ABSTRACT

BACKGROUND: It is unclear whether caregivers' concern about child weight impacts their non-responsive feeding practices. This systematic review aimed to examine their relationships. METHODS: A systematic search of PubMed, Embase, PsycINFO, Web of Science core collection, CINAHL and grey literature was conducted from inception to March 2022, following PRISMA guidelines. Data synthesis was performed using a semi-quantitative approach and a meta-analysis. RESULTS: A total of 35 studies with 22,933 respondents were included in the review for semi-quantitative analyses. Thirty-four studies examined 52 associations between concern about child weight and restriction with 40 statistically significant associations being observed. A total of 34 relationships between concern about child weight and pressure to eat were investigated, with 12 being statistically significant. The pooled regression coefficients (ß) demonstrated that caregivers' concern about child overweight was positively associated with restriction (ß = 0.22; 95%CI: 0.12, 0.31), negatively associated with use of food as a reward (ß = -0.06; 95%CI: -0.11, -0.01), and not statistically associated with pressure to eat (ß = -0.05; 95%CI: -0.13, 0.04). The pooled odds ratios (ORs) indicated that caregivers who were concerned about child overweight were found to use restrictive feeding more often (OR = 2.34; 95%CI: 1.69, 3.23), while less frequently adopting pressure to eat (OR = 0.76; 95%CI: 0.59, 0.98) compared with those without concerns. The results also showed that caregivers who were concerned about child underweight were more likely to force their children to eat (OR = 1.83; 95%CI: 1.44, 2.33) than those without concerns. CONCLUSION: Caregivers' concern about child weight may be an important risk factor for non-responsive feeding practices. Thus, interventions are needed to focus on managing and relieving caregivers' excessive concern about child weight, especially overweight, which may optimize feeding practices and subsequently contribute to child health.


Subject(s)
Caregivers , Overweight , Body Mass Index , Child , Feeding Behavior , Humans , Parenting , Surveys and Questionnaires
8.
Angew Chem Int Ed Engl ; 61(21): e202200215, 2022 May 16.
Article in English | MEDLINE | ID: mdl-35263015

ABSTRACT

We report here a new method for the synthesis of organohydrosilanes from phenols and ketones. This method is established through reductive C-Si coupling of chlorohydrosilanes via unconventional Si-Cl cleavage. The reaction offers access to aryl- and alkenylhydrosilanes with a scope that is complementary to those of the established methods. Electron-rich, electron-poor, and ortho-/meta-/para-substituted (hetero)aryl electrophiles, as well as cyclic and acyclic alkenyl electrophiles, were coupled successfully. Functionalities, including Grignard-sensitive groups (e.g., primary amine, amide, phenol, ketone, ester, and free indole), acid-sensitive groups (e.g., ketal and THP protection), alkyl-Cl, pyridine, furan, thiophene, Ar-Bpin, and Ar-SiMe3 , were tolerated. Gram-scale reaction, incorporation of -Si(H)R2 into complex biologically active molecules, and derivatization of formed organohydrosilanes are demonstrated.

9.
J Am Chem Soc ; 143(12): 4536-4542, 2021 03 31.
Article in English | MEDLINE | ID: mdl-33724807

ABSTRACT

The regiocontrolled functionalization of 1,3-dienes has become a powerful tool for divergent synthesis, yet it remains a long-standing challenge for aliphatic substrates. Herein, we report a reductive approach for a branch-selective 1,2-hydrovinylation of aliphatic 1,3-dienes with R-X electrophiles, which represents a new selectivity pattern for diene functionalization. Simple butadiene, aromatic 1,3-dienes, and highly conjugated polyene were also tolerated. The combination of Ni(0) and the phosphine-nitrile ligand generally resulted in >20:1 regioselectivity with the retention of the geometry of the C3-C4 double bonds. This reaction proceeds with a broad substrate scope, and it allows for the conjugation of two biologically active units to form more complex polyene molecules, such as tetraene and pentaene as well as heptaene.

10.
Environ Sci Pollut Res Int ; 26(5): 4764-4776, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30565113

ABSTRACT

Energy cooperation has been emphasized strongly in the Belt and Road (B&R) initiative. Therefore, the energy efficiency of China has attracted much attention from experts. However, relevant studies are still insufficient. This paper analyzes the total factor energy efficiency (TFEE) and its influencing factors of 17 B&R key regions from 2005 to 2015. We use the ratio of target energy input and actual energy input to calculate the regional TFEE under environmental constraints. The Malmquist index and the Tobit model are applied to investigate the internal and external influences of TFEE. Measurement analysis shows that the TFEE of the B&R key regions has not improved in recent years and it is unbalanced during the study period. Regions in the east area have the highest TFEE; regions in the west area have the second high TFEE; and regions in the north area have the lowest TFEE. Regression analysis shows that for the B&R key regions, technical changes, coal consumption, research and development, and environmental pollution have mainly negative effects on TFEE; pure efficiency changes, scale efficiency changes, economic structure, opening up, and government finance have mainly positive effects on TFEE. Finally, precise policy implications are proposed.


Subject(s)
Energy-Generating Resources , Environmental Pollution , China , Coal , Efficiency , Energy-Generating Resources/economics , Energy-Generating Resources/statistics & numerical data , Models, Theoretical , Regression Analysis
11.
Environ Sci Pollut Res Int ; 24(24): 19859-19873, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28687994

ABSTRACT

Nowadays, environment problem has become the international hot issue. Experts and scholars pay more and more attention to the energy efficiency. Unlike most studies, which analyze the changes of TFEE in inter-provincial or regional cities, TFEE is calculated with the ratio of target energy value and actual energy input based on data in cities of prefecture levels, which would be more accurate. Many researches regard TFP as TFEE to do analysis from the provincial perspective. This paper is intended to calculate more reliably by super efficiency DEA, observe the changes of TFEE, and analyze its relation with TFP, and it proves that TFP is not equal to TFEE. Additionally, the internal influences of the TFEE are obtained via the Malmquist index decomposition. The external influences of the TFFE are analyzed afterward based on the Tobit models. Analysis results demonstrate that Heilongjiang has the highest TFEE followed by Jilin, and Liaoning has the lowest TFEE. Eventually, some policy suggestions are proposed for the influences of energy efficiency and study results.


Subject(s)
Efficiency, Organizational , China , Models, Theoretical , Socioeconomic Factors
12.
J Hazard Mater ; 239-240: 135-41, 2012 Nov 15.
Article in English | MEDLINE | ID: mdl-23022415

ABSTRACT

This study investigated the change of hazardous materials in coking wastewater at different treatment stages (anaerobic, anaerobic/aerobic, anaerobic/aerobic/photo degradation, anaerobic/aerobic/ozone oxidation treatment) and the effects of them on the development of maize embryos and the activity of amylase and protease in maize seeds. Moreover the interaction of refractory organic matters in the wastewater at different treatment stages with amylase and protease also were determined in vitro. The results show that the biodegradable and the refractory organic compounds in the wastewater both can affect maize embryo development (germination inhibition rate is 19.3% for biodegradable organic compounds). As the treatment stage preceding, the inhibition effect of coking wastewater on the development of the maize embryo (for germination inhibition rates change from 49.3% to 24.6%) and on enzymatic activity (inhibition rates change from 63.9% to 22.4% for amylase) decreases gradually, but the photo-degradation treatment to anaerobic/aerobic effluent can increase its toxicity. The changes in the ability of the refractory organic compounds to bind with enzyme proteins, combined with the analysis of the organic components by GC/MS, show that in the process of coking wastewater treatment no new toxic chemicals were produced.


Subject(s)
Coke , Seeds/drug effects , Wastewater/toxicity , Water Pollutants, Chemical/toxicity , Zea mays/drug effects , Ammonia/analysis , Ammonia/toxicity , Amylases/metabolism , Biological Oxygen Demand Analysis , Cyanides/analysis , Cyanides/toxicity , Germination/drug effects , Peptide Hydrolases/metabolism , Seeds/enzymology , Seeds/growth & development , Waste Disposal, Fluid/methods , Wastewater/analysis , Water Pollutants, Chemical/analysis , Zea mays/enzymology , Zea mays/growth & development
13.
J Photochem Photobiol B ; 98(2): 152-8, 2010 Feb 12.
Article in English | MEDLINE | ID: mdl-20044266

ABSTRACT

The effects of supplemental UV-B radiation on Taxus chinensis var. mairei were studied. Leaf traits, gas exchange parameters and the concentrations of photosynthetic pigments, cellular defense system products, secondary metabolites and ultrastructure were determined. UV-B radiation significantly decreased leaf area (p<0.05). Leaf number, secondary branch number, leaf weight per plant and leaf moisture all increased dramatically (p<0.05). Neither the leaf weight nor the specific leaf weight (SLW) exhibited significant differences between ambient and enhanced UV-B radiation. Gas exchange parameters were all dramatically reduced by enhanced UV-B radiation (p<0.05). The contents of chlorophyll and the chlorophyll a/b ratio were not distinctly affected by UV-B radiation, while carotenoids content significantly decreased (p<0.05). Supplemental UV-B treatment induced significant flavonoid accumulation (p<0.05), which was able to protect plant from radiation damage. Meanwhile, the appendage content, abaxial stomatal density, papilla density and particulate matter content in substomatic chambers increased noticeably by supplemental UV-B radiation, whereas the aperture size of single stomata was diminished. The number and area of plastoglobuli were apparently reduced by UV-B radiation, but stroma and grana lamellae were not destroyed. Our results demonstrated that T. chinensis var. mairei can activate several defense mechanisms against oxidative stress injury caused by supplemental UV-B radiation.


Subject(s)
Taxus/radiation effects , Ultraviolet Rays , Ascorbate Peroxidases , Catalase/metabolism , Flavonoids/analysis , Paclitaxel/analysis , Peroxidases/metabolism , Plant Leaves/chemistry , Plant Leaves/radiation effects , Plant Leaves/ultrastructure , Plant Transpiration , Superoxide Dismutase/metabolism , Taxus/chemistry , Taxus/enzymology
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