925 resultados para Joyce


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Lenticel discolouration (LD) is a common disorder of mango fruit around the world. It results in poor appearance and disappointment of consumers. LD is exacerbated by treatment of mango fruit with gamma irradiation for insect disinfestation. The issue is problematic on the relatively new mango cultivar 'B74' and may represent an oxidative browning process. With a view to reducing irradiationinduced LD on 'B74', postharvest wax (one and three layers; 75% carnauba wax) and antioxidant (100 mM ascorbic acid, 100 mM calcium chloride, 10, 50 and 100 mM calcium ascorbate) dip treatments were investigated. Treatment of green mature fruit with three layers of wax prior to exposure to 557 Gy gamma irradiation reduced LD by 40% relative to the non-waxed control. However, the fruit failed to ripen properly as evidenced by delayed skin colour change, retarded softening and increased skin browning as compared to the controls and fruit coated with one layer of wax. Treatment with one layer of wax did not reduce LD. Mechanistically, the responses suggest that air exchange plays a pivotal role in LD. A lowered oxygen concentration in the lenticels may reduce the disorder after irradiation treatment. Postharvest treatments with the various antioxidants failed to reduce LD. Rather, all antioxidant treatments at the test concentrations, except calcium chloride, significantly increased skin browning.

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The fruit of certain mango cultivars (e.g., 'Honey Gold') can develop blush on their skin. Skin blush due to red pigmentation is from the accumulation of anthocyanins. Anthocyanin biosynthesis is related to environmental determinants, including light received by the fruit. It has been observed that mango skin blush varies with position in the tree canopy. However, little investigation into this spatial relationship has been conducted. The objective of this preliminary study was to describe a 'Honey Gold' mango tree by capturing its three-dimensional (3D) architecture. A light path tracing model QuasiMC was then used to predict light received by fruit. The use of this 3D model was to better understand the relationship between mango fruit skin blush and fruit position in the canopy. The digitised mango tree mimicked the real tree at a high level of detail. Observations on mango skin blush distribution supported the proposition that sunlight exposure is an absolute requirement for anthocyanin development. No blush development occurred on shaded skin. It was affirmed that 3D mapping could allow for virtual experiments. For example, for virtual canopy thinning (e.g., 'window pruning') to admit more sunlight with a view to improve fruit blush. Improvements to 3D modelling of mango skin blush could focus on increasing accuracy, e.g., measurement of leaf light reflectance and transmission and the inclusion of the effect shading by branches.

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γ-Irradiation doses of 0.5 (target) and 1.0 (high) kGy were applied as insect disinfestation treatments to 'Kensington Pride' mango fruit. The effects of these treatments on fruit physicochemical properties and aroma volatile production were investigated and compared to non-irradiated controls. There were no significant effects of the irradiation treatments on flesh total soluble solids content. However, the loss of green skin colour usually associated with fruit ripening was inhibited by irradiation at both 0.5 and 1.0 kGy by approximately 32 and 52%, respectively, relative to non-irradiated fruit. Fruit exposed to 0.5 and 1.0 kGy exhibited a 58 and 80% reduction in emission of a-terpinolene volatiles, respectively. Thus, γ-irradiation at 0.5 and 1.0 kGy can have an adverse effect on 'Kensington Pride' mango fruit aroma volatile production and skin colouration.

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An inherently short vase life is a problematic characteristic of cut flowers and foliage for otherwise attractive native Australian Acacia spp. Reasons underlying the poor postharvest water uptake of cut acacia stems have been elusive. A. holosericea was used to investigate possible bacteria-induced and wound-induced xylem occlusion. The effects of bacterial-and wound-induced xylem blockage on water uptake were investigated by light and scanning and transmission electron microscopy. Observations were made on cut stems that stood into either deionised water (DIW; control) or 0.5 mM Cu2+ solution and on stems pulsed with 2.2 mM Cu2+ solution and then stood into DIW. The stem-end region of cut A. holosericea that stood into DIW or Cu2+ solution became covered with bacterial growth after 3 days. Regardless of the bacterial biofilm, the Cu2+ treated stems had improved water relations and vase life. Therefore, the biofilm had little or no effect on cut A. holosericea longevity. Further observations revealed presence of a vessel-occluding substance (gel) originating from axial parenchyma cells in direct physical contact with xylem vessels. The gel exuded into vessel lumens through pit membranes, evidently as a wound-response. Xylem occlusion by gels in A. holosericea may be especially problematic due to an abundance of secretory contact cells relative to xylem elements. Nonetheless, active wound response processes may be the key determinant of short postharvest longevity for this and possibly other cut Acacia spp. Cu2+ treatments, however, disrupted the secretory function of axial parenchyma cells thereby preventing vessel occlusion by the gels.

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Objective: To evaluate the nutritional counseling offered to children and adolescents with disabilities in the municipality of Santa Cruz, RN, Brazil. Methods: Observational, crosssectional, population-based study, developed from May to December 2013, with 102 children and adolescents attending a Children’s Rehabilitation Center. We conducted socioeconomic, demographic, health and lifestyle assessments, and evaluated the received nutritional assistance (whether they had received nutritional counseling from any health professional in relation to food and nutrition, how often it occurred and which professional conducted such counseling). Results: Only 37% (n=37) of parents had received some nutritional guidance. Regarding the frequency of counseling, only 11.8% (n=4) of the youngsters received it 7 or more times/year; 23.5% (n=8) received it 2 to 6 times/year; and most (64.7 %, n=22) received it 1 time/year or less. The length of the nutritional counseling was short: the majority (64.7%, n=22) received only one guidance session throughout the whole period attending the institution, and less than 15% (n=5) received counseling for more than six consecutive months. For the majority (73.5%, n=25), the amount of time receiving nutritional guidance has not reached half of the monitoring period. Nutritional counseling was carried out mainly by nutritionists (89.2%, n=33). Conclusion: There was a low frequency of nutritional counseling directed specifically to the disabilities presented by the participants. When such activity was conducted, it occurred irregularly during the participant´s follow-up, only during a short period of time, and lacking connection with the monitoring by the multidisciplinary team.

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The temporal passage of fruit through the supply chain and the selection of consumable fruit by shoppers depend primarily upon fruit firmness. Traditionally, fruit firmness measuring methods, like Effegi and conical probes, are relatively inefficient and destructive. Simple, accurate and non-damaging methods of measuring fruit firmness are ideally required to help assure eating quality to the consumer without fruit wastage. The firmness of 'Hass' avocado fruit at a range of ripening stages was measured with the various different firmness measuring techniques of the Sinclair iQ Firmness Tester (SIQFT), the Electronic Firmometer (EF), the Analogue Firmness Meter (AFM) and hand squeezing. Measurements were made by each method at different points on the same fruit. Destructive bruise assessment was performed 48 h later, thereby allowing sufficient time for fruit to express any bruising resulting from the act of firmness measurements. Non-linear relationships were determined between fruit firmness values measured with the different techniques. The adjusted R2 for the relationship between the SIQFT and the EF was 91.6%. For the SIQFT and the AFM, the adjusted R2 was 73.7%. It was 77.7% for the SIQFT and hand squeezing. A significantly (P<0.05) high incidence of bruising was associated with firmness assessment by the EF as compared with either the SIQFT or the AFM. Among the methods compared, the SIQFT was non-damaging compared with the EF and relatively efficient for measuring the firmness. This instrument merits consideration as a quality control tool of choice in 'Hass' avocado supply chains.

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Postharvest treatments with nano-silver (NS) alleviate bacteria-related stem blockage of some cut flowers to extend their longevity. Gladiolus (Gladiolus hybridus) is a commercially important cut flower species. For the first time, the effects of NS pulses on cut gladiolus ‘Eerde’ spikes were investigated towards reducing bacterial colonization of and biofilm formation on their stems. As compared with a deionized water (DIW) control, pulse treatments with NS at 10, 25 and 50 mg L−1 for 24 h significantly (P ≤ 0.05) prolonged the vase life of cut gladiolus spikes moved into vases containing DIW. The NS treatments enhanced floret ‘opening rate’ and ‘daily ornamental value’. Although there were no significant differences among NS treatments, a 25 mg L−1 NS pulse treatment tended to give the longest vase life and the best ‘display quality’. All NS pulse treatments significantly improved water uptake by and reduced water loss from flowering spikes, thereby delaying the loss of water balance and maintaining relative fresh weight. Fifty (50) mg L−1 NS pulse-treated cut gladiolus spikes tended to exhibit the most water uptake and highest water balance over the vase period. However, there was no significant difference between 25 and 50 mg L−1 NS pulse treatments. Observations of stem-end bacterial proliferation during the vase period on cut gladiolus spikes either with or without NS pulse treatments were performed by confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). As compared to the control treatment, they revealed that the 25 mg L−1 NS pulse treatment effectively inhibited bacterial colonization and biofilm formation on the stem-end cut surface and in the xylem vessels, respectively. In vitro culture of the bacterial microflora and analysis of biofilm architecture using CLSM revealed that NS treatment restricted bacterial biofilm formation. After static culture for 24 h at 35 °C with 25 mg L−1 NS in the medium, no biofilm form or structure was evident. Rather, only limited bacterial cell number and scanty extracellular polysaccharide (EPS) material were observed. In contrast, mature bacterial biofilm architecture comprised of abundant bacteria interwoven with EPS formed in the absence of NS.

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In major cities today, there are neighborhoods that have been continually underserved and as a result are in decay. Private investors and developers turn to these particular neighborhoods, propose large developments that gentrify these areas, displacing communities and with them their social, political, and economic issues. The purpose of this thesis is to analyze South West, Baltimore, a community composed of 8 neighborhoods on the verge of being gentrified, by incoming development. Through investigating the key issues present in this community for many years, this thesis will attempt to develop a catalytic environment, which will facilitate change within the community by providing a place for its members to help tackle these issues, improving their circumstances, and the circumstances of the neighborhoods they form part of.

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The managing Conselho of public politics constitute one of the main experiences of democracy in Brazil contemporary representing a conquest for construction of a democratic institutionalism. The historical newness consists of the intensification and the institutionalization of the dialogue between government and society - in public and plural canals - as condition for an allocation more efficient joust and of the public resources. In this context the present study it objectified to understand from readings of the performance of represented group of bencheses the dynamics of functioning of the Tourist Conselho Pólo Costa das Dunas while space of participation and social control. The bibliographical research contemplated diverse sources in order to compile knowledge of credential authors in the quarrel of inherent subjects to the civil society and the public sphere to the construction of the citizenship to the conception formation and dynamics of the social control through Conselho of public politics. A qualitative perspective the case study was adopted as research method and for attainment of the data interviews with the members of the Conselho had been carried through beyond consultation the referring documents the dynamics of functioning of the Conselho. The profiles capacities and limitations of the members of the Conselho had been identified constitution social and dynamic organization of functioning of the Conselho and the readings of the members of the Conselho concerning the power to decide instances and participation. The results had shown that the allotment of being able in the Conselho does not occur of equal form. The functions of coordination of the activities of the Conselho are assumed by the representatives of the public agencies. Level of qualification of council members also if presents as difficulty to development of activities of Conselho since the majority of the interviewed ones disclosed unreliability and unfamiliarity when thematic specific that runs away from its organizacional reality they are boarded in the assemblies. Of this form the Conselho if presents more as half of institutional legitimation of what half of characterization of the creation of a public sphere properly said. Finally he could himself be concluded that a democratic culture inexists that inside crosses practical the institutional ones of the Conselho thus limiting the possibility to reach the effective social control of the public politics of tourism in the Rio Grande do Norte

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The principalship has changed significantly over the past 20 years. Today’s principals must be effective instructional leaders, managers of large facilities, and experts at analyzing data to successfully meet the accountability demands of high-stakes testing, along with state, and federal mandates. The primary purpose of this quantitative study was to examine how 43 first- and second-year sitting school principals perceived their mentoring experiences and the degree to which a principal mentoring program—offered by their large urban school district—was effective in building their leadership capacity. A second purpose of this inquiry was to understand these principals’ perceptions of the most beneficial aspects of the mentoring program. The study used quantitative data gathered via an online questionnaire distributed during Fall 2015. The results indicated that respondents perceived that the components of the large urban school-mentoring program were generally effective in training principal mentees to become highly-effective school leaders. This study enriches the literature on mentoring by providing the voices of first and second year school leaders to add depth to the characteristics of successful mentoring programs.