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81.
Christian Thierfelder Pauline Chivenge Walter Mupangwa Todd S. Rosenstock Christine Lamanna Joseph X. Eyre 《Food Security》2017,9(3):537-560
Climate resilient cropping systems are required to adapt to the increasing threats of climate change projected for Southern Africa and to better manage current climate variability. Conservation agriculture (CA) has been proposed among technologies that are climate-smart. For a cropping system to be labelled “climate-smart” it has to deliver three benefits: a) adapt to the effects of climate and be of increased resilience; b) mitigate climate effects by sequestering carbon (C) and reducing greenhouse gas emissions (GHG); and c) sustainably increase productivity and income. Research on smallholder farms from Southern Africa was analysed to assess if CA can deliver on the three principles of climate-smart agriculture. Results from Southern Africa showed that CA systems have a positive effect on adaptation and productivity, but its mitigation potential lags far behind expectations. CA systems maintain higher infiltration rates and conserve soil moisture, which helps to overcome seasonal dry-spells. Increased productivity and profitability were recorded although a lag period of 2–5 cropping seasons is common until yield benefits become significant. Immediate economic benefits such as reduced labour requirements in some systems will make CA more attractive in the short term to farmers who cannot afford to wait for several seasons until yield benefits accrue. The available data summarizing the effects of CA on soil organic C (SOC) and reductions in greenhouse gases, are often contradictory and depend a great deal on the agro-ecological environment and the available biomass for surface residue retention. There is an urgent need for more research to better quantify the mitigation effects, as the current data are scanty. Possible co-interventions such as improved intercropping/relay cropping systems, agroforestry and other tree-based systems may improve delivery of mitigation benefits and need further exploration. 相似文献
83.
84.
Schretlen David; Jayaram Geetha; Maki Pauline; Park Karen; Abebe Solomé; DiCarlo Margaret 《Canadian Metallurgical Quarterly》2000,109(1):134
Although cognitive deficits often accompany severe mental illness, their implications for everyday functioning remain poorly understood. In this study, an occupational therapist (OT) rated the everyday functioning of 105 adult psychiatric patients. Using demographic, clinical, and cognitive variables, the authors tested alternative models to account for the observed variability in OT ratings. Although age, education, and the presence of schizophrenia each contributed to a model that accounted for 27% of the variation in functional independence, adding terms for auditory divided attention and verbal learning increased the proportion of explained variance to 45% and decreased the beta weights for age and education—but not schizophrenia—to nonsignificant levels. These findings demonstrate the relevance of cognitive performance to everyday functioning in severe mental illness. They are discussed with respect to hypothesized determinants of psychiatric disability. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
85.
Piming Ma Denka G Hristova‐Bogaerds Pauline Schmit Johannes G P Goossens Piet J Lemstra 《Polymer International》2012,61(8):1284-1293
Poly(lactic acid)/poly(ethylene‐co‐vinyl acetate)/starch (PLA/EVA/starch) ternary blends were prepared by multi‐step melt processing (reactive extrusion) in the presence of maleic anhydride (MA), benzoyl peroxide and glycerol. The effects of MA and glycerol concentration on the morphology and properties of the PLA/EVA/starch blends were studied using scanning electron microscopy, transmission electron microscopy, atomic force microscopy, the Molau experiment, dynamic mechanical thermal analysis and differential scanning calorimetry etc. The plasticization and compatibilization provided a synergistic effect to these blends accompanied by a significant reduction in starch particle size and an increase in interfacial adhesion. Starch was finely dispersed in the ternary blends with a dimension of 0.5 ? 2 µm. Furthermore, EVA‐coated starch or a starch‐in‐EVA type of morphology was observed for the reactively compatibilized PLA/EVA/starch blends. The EVA with starch gradually changed into a co‐continuous phase with increasing MA concentration. Consequently, the toughness of the blends was improved. Since property stability of starch is an issue, the tensile properties of these blends were measured after different storage times and the blends showed good property stability. Copyright © 2012 Society of Chemical Industry 相似文献
86.
Insights into Carbopol gel formulations: Microscopy analysis of the microstructure and the influence of polyol additives
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Pauline Lefrançois Emmanuel Ibarboure Bruno Payré Etienne Gontier Jean‐François Le Meins Christophe Schatz 《应用聚合物科学杂志》2015,132(46)
Carbopol is a family of high molecular weight cross‐linked poyacrylic acids widely used as thickening agents in several industrial applications. In this work, the structure of Carbopol 974P NF was investigated at pH 7.4 by means of capillary viscometry, dynamic rheology, fluorescence microscopy, and electron microscopy in the dilute and semi‐dilute (hydrogel) state. Especially, high‐pressure freezing technique has proved to be a technique of choice to visualize the Carbopol hydrogel microstructure through cryo‐scanning electron microscopy analysis without artifacts related to the formation of ice crystals. It has been shown that the Carbopol hydrogel has a hierarchical structure made of large spherical entities of a few micrometers in size packed together and composed of much smaller agglomerated microgel particles. In addition, fluorescence and electron microscopies have pointed out that the presence of polyol additives in the gel formulation favors the formation of more dense or jammed structure, probably through hydrogen bonding. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42761. 相似文献
87.
Anastasiou R Leverrier P Krestas I Rouault A Kalantzopoulos G Boyaval P Tsakalidou E Jan G 《International journal of food microbiology》2006,108(3):301-314
Dairy propionibacteria are present in Graviera Kritis, a traditional Gruyère-type cheese made without added propionic starter. Ten isolated strains were identified by a combination of SDS-PAGE, species-specific PCR and according to their ability to ferment lactose. They were all found to belong to the Propionibacterium freudenreichii subsp. shermanii species. Because of the stressing Gruyère technology, which includes cooking at 52 to 53 degrees C their thermotolerance was investigated at 55 degrees C. Thermotolerant and thermosensitive strains were clearly discriminated. Interestingly, the reference strain CIP 103027 belongs to the sensitive subset. One sensitive strain, ACA-DC 1305 and one tolerant, ACA-DC 1451, were selected for further study and compared to CIP 103027. For the sensitive strains ACA-DC 1305 and CIP 103027, heat pre-treatment at 42 degrees C conferred thermoprotection of cells at the lethal temperature of 55 degrees C, while there was less effect on the tolerant ACA-DC 1451. No cross-protection of salt-adapted cells against heat stress was observed for none of the strains. Differential proteomic analysis revealed distinct but overlapping cell responses to heat stress between sensitive and tolerant strains. Thermal adaptation upregulated typical HSPs involved in protein repair or turnover in the sensitive one. In the tolerant one, a distinct subset of proteins was overexpressed, whatever the temperature used, in addition to HSPs. This included enzymes involved in propionic fermentation, amino acid metabolism, oxidative stress remediation and nucleotide phosphorylation. These results bring new insights into thermoprotection in propionibacteria and the occurrence of divergent phenotypes within a same subspecies. 相似文献
88.
Nelis Delphine; Kotsou Ilios; Quoidbach Jordi; Hansenne Michel; Weytens Fanny; Dupuis Pauline; Mikolajczak Mo?ra 《Canadian Metallurgical Quarterly》2011,11(2):354
This study builds on earlier work showing that adult emotional competencies (EC) could be improved through a relatively brief training. In a set of 2 controlled experimental studies, the authors investigated whether developing EC could lead to improved emotional functioning; long-term personality changes; and important positive implications for physical, psychological, social, and work adjustment. Results of Study 1 showed that 18 hr of training with e-mail follow-up was sufficient to significantly improve emotion regulation, emotion understanding, and overall EC. These changes led in turn to long-term significant increases in extraversion and agreeableness as well as a decrease in neuroticism. Results of Study 2 showed that the development of EC brought about positive changes in psychological well-being, subjective health, quality of social relationships, and employability. The effect sizes were sufficiently large for the changes to be considered as meaningful in people's lives. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
89.
In her article (see record 2000-05399-010) in this issue, P. Bryan measured collaborative law by whether it improves the economic conditions of women after divorce, arguing that far broader reform of divorce laws is required to achieve that goal. Collaborative law aims at different goals. Bryan also argued that collaborative law resembles mediation, that mediation harms women and children, and that the same will happen in collaborative law. In fact, Bryan makes faulty analogies between mediation and collaborative law, misconstrues the literature on mediation, and criticizes collaborative law for human failings arising in any profession or dispute resolution modality. Fair-minded research questions would serve the evolution of this new model better than such ill-founded arguments in support of apparently preconceived conclusions. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
90.
Miville Marie L.; Gelso Charles J.; Pannu Raji; Liu Will; Touradji Pegah; Holloway Pauline; Fuertes Jairo 《Canadian Metallurgical Quarterly》1999,46(3):291
Universal-diverse orientation was defined as an attitude of awareness and acceptance of both the similarities and differences that exist among people. A 45-item scale developed to measure the construct was administered to 4 separate samples (ns?=? 93, 111, 153, and 135). Internal consistency and retest reliability for the Miville-Guzman Universality-Diversity Scale (M-GUDS) ranged from .89 to .95. The M-GUDS significantly correlated in theoretically predicted ways with measures of racial identity, empathy, healthy narcissism, feminism, androgyny, homophobia, and dogmatism (the last 2 correlations were negative). The M-GUDS displayed discriminant validity by failing to correlated with Scholastic Achievement Test Verbal Scores, although mixed results were obtained with social desirability. In summary, the data suggest considerable reliability and initial construct validity for the M-GUDS. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献