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1.
Chemosphere ; 352: 141403, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38368967

RESUMO

High concentrations of metals and sulfates in acid mine drainage (AMD) are the cause of the severe environmental hazard that mining operations pose to the surrounding ecosystem. Little study has been conducted on the cost-effective biological process for treating high AMD. The current research investigated the potential of the proposed carbon source and sulfate reduction bacteria (SRB) culture in achieving the bioremediation of sulfate and heavy metals. This work uses individual and combinatorial bioaugmentation and bio-stimulation methods to bioremediate acid-mine-influenced groundwater in batch microcosm experiments. Bioaugmentation and bio-stimulation methods included pure culture SRB (Desulfovibrio vulgaris) and microsized oil droplet (MOD) by emulsifying corn oil. The research tested natural attenuation (T 1), bioaugmentation (T2), biostimulation (T3), and bioaugmentation plus biostimulation (T4) for AM-contaminated groundwater remediation. Bioaugmentation and bio-stimulation showed the greatest sulfate reduction (75.3%) and metal removal (95-99%). Due to carbon supply scarcity, T1 and T2 demonstrated 15.7% and 27.8% sulfate reduction activities. Acetate concentrations in T3 and T4 increased bacterial activity by providing carbon sources. Metal bio-precipitation was substantially linked with sulfate reduction and cell growth. SEM-EDS study of precipitates in T3 and T4 microcosm spectra indicated peaks for S, Cd, Mn, Cu, Zn, and Fe, indicating metal-sulfide association for metal removal precipitates. The MOD provided a constant carbon source for indigenous bacteria, while Desulfovibrio vulgaris increased biogenic sulfide synthesis for heavy metal removal.


Assuntos
Desulfovibrio vulgaris , Desulfovibrio , Metais Pesados , Biodegradação Ambiental , Óleo de Milho , Zea mays , Ecossistema , Bactérias , Ácidos , Sulfatos , Carbono , Sulfetos
2.
Hous Stud ; 38(1): 128-151, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36861113

RESUMO

Tenant-based rental assistance has received much attention as a tool to ameliorate American poverty and income segregation. We examined whether a tenant-based voucher program improves long-term exposure to neighborhood opportunity overall and across multiple domains-social/economic, educational, and health/environmental-among low-income families with children. We used data from the Moving to Opportunity (MTO) experiment (1994-2010) with a 10- to 15-year follow-up period and used an innovative and multidimensional measure of neighborhood opportunities for children. Compared with controls in public housing, MTO voucher recipients experienced improvement in neighborhood opportunity overall and across domains during the entire study period, with a larger treatment effect for families in the MTO voucher group who received supplementary housing counseling, than the Section 8 voucher group. Our results also suggests that effects of housing vouchers on neighborhood opportunity may not be uniform across subgroups. Results from model-based recursive partitioning for neighborhood opportunity identified several potential effect modifiers for housing vouchers, including study sites, health and developmental problems of household members, and having vehicle access.

3.
Food Chem ; 403: 134361, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36162266

RESUMO

Self-assembly (formation and crystallization) kinetics of short-chain glucan aggregates (SCGAs) prepared at isothermal conditions (4, 20, 40, and 60℃) with or without nucleation (4℃, 1 h) were investigated. The fastest formation and crystallization rates of SCGA were observed when short-chain glucan was stored at 4℃ and 20℃, respectively. SCGA was not formed at 60℃. However, nucleation resulted in SCGA forming-ability at 60℃. Moreover, nucleation increased the yield in all temperature conditions. SCGA with nucleation decreased the crystal melting transition temperature range. All SCGAs had nanosized particles (<500 nm) with B-type crystal patterns regardless of temperature and nucleation. Consequently, self-assembly temperature and presence of nucleation step could change the physicochemical characteristics of SCGA, and manipulation of the nucleation step is expected to be an effective method to increase the yield of SCGA and produce SCGA at high temperature.


Assuntos
Glucanos , Cinética , Cristalização , Temperatura , Temperatura de Transição
4.
Alcohol Clin Exp Res ; 46(9): 1695-1709, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36121443

RESUMO

PURPOSE: Neighborhood context may influence alcohol use, but effects may be heterogeneous, and prior evidence is threatened by confounding. We leveraged a housing voucher experiment to test whether housing vouchers' effects on alcohol use differed for families of children with and without socioemotional health or socioeconomic vulnerabilities. TRIAL DESIGN: In the Moving to Opportunity (MTO) study, low-income families in public housing in five US cities were randomized in 1994 to 1998 to receive one of three treatments: (1) a housing voucher redeemable in a low-poverty neighborhood plus housing counseling, (2) a housing voucher without locational restriction, or (3) no voucher (control). Alcohol use was assessed 10 to 15 years later (2008 to 2010) in youth ages 13 to 20, N = 4600, and their mothers, N = 3200. METHODS: Using intention-to-treat covariate-adjusted regression models, we interacted MTO treatment with baseline socioemotional health vulnerabilities, testing modifiers of treatment on alcohol use. RESULTS: We found treatment effect modification by socioemotional factors. For youth, MTO voucher treatment, compared with controls, reduced the odds of ever drinking alcohol if youth had behavior problems (OR = 0.26, 95% CI [0.09, 0.72]) or problems at school (OR = 0.46, [0.26, 0.82]). MTO low-poverty treatment (vs. controls) also reduced the number of drinks if their health required special medicine/equipment (OR = 0.50 [0.32, 0.80]). Yet treatment effects were nonsignificant among youth without socioemotional vulnerabilities. Among mothers of children with learning problems, MTO voucher treatment (vs. controls) reduced past-month drinking (OR = 0.69 [0.47, 0.99]), but was harmful otherwise (OR = 1.22 [0.99, 1.45]). CONCLUSIONS: For low-income adolescents with special needs/socioemotional problems, housing vouchers protect against alcohol use.


Assuntos
Habitação Popular , Projetos de Pesquisa , Adolescente , Adulto , Criança , Cidades , Humanos , Pobreza , Características de Residência , Adulto Jovem
5.
Food Sci Biotechnol ; 31(5): 561-570, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35529684

RESUMO

The effects of concentration, temperature, and time on infusion of fluorescein into corn and waxy rice starches and their controlled release pattern were investigated. At low fluorescein concentration (1 µM), temperature significantly affected infusion efficiency. At high fluorescein concentration (50-150 µM), temperature showed little effect; fluorescein concentration significantly affected infusion efficiency. Corn starch showed relatively higher infusion efficiency than waxy rice starch at high concentration. During controlled release, 50% and 81% of infused fluorescein were released from corn and waxy rice starches, respectively, after bacterial α-amylase treatment. However, 61% and 68% of infused fluorescein were released from corn and waxy rice starches, respectively, after pancreatic α-amylase treatment. The dextrose equivalent (DE) value revealed similar patterns, suggesting that degradation of starch by different α-amylases is a major factor affecting release of fluorescein from starch granules. Moreover, granule size of starch greatly affected enzymatic hydrolysis and controlled release in this system. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-022-01059-2.

6.
Hous Policy Debate ; 32(2): 369-385, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35400983

RESUMO

While scholars have acknowledged that shrinking federal resources for low-income housing programs increase economic inequality across U.S. society as a whole, the question of how the allocation of these resources affects inequality among the poor has received little attention. Using a mixed methods approach, this study examines local administrative practices of distributing scare housing resources and the potential redistributive effects of those choices. Analyses of administrative and qualitative data collected from local housing agencies suggest that local administrative practices of managing a waitlist disadvantage residentially unstable applicants. Juxtaposing this finding with results from the Survey of Income and Program Participation suggests that among those who are income-eligible for program participation, poorer individuals have a greater likelihood of experiencing residential instability, thus compounding their disadvantage in the competition for a housing voucher.

7.
Food Sci Biotechnol ; 31(3): 261-274, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35273817

RESUMO

Starch is often subjected to denaturation treatment to improve its useful properties and eliminate its shortcomings. Various methods have been developed to produce modified starches with different properties and for a variety of uses. Because physically modified starch can be produced without chemical substances or biological agents, the modification method is very simple and inexpensive, and the resulting material can be used as clean label starch. Among these physical modification technologies, heat moisture treatment (HMT) is a universally valid technology, but little is known about pressure moisture treatment (PMT)-related technology. Physical modification of starch using PMT results in new functions and value-added characteristics required by industry, and PMT has the potential to produce starch with new functions. In this paper, PMT-related technologies for physically modified starch, the difference between PMT and the hydro-thermal treatment, and clean label starch manufacturing using HMT and PMT were investigated.

8.
Food Sci Biotechnol ; 30(10): 1339-1346, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34721929

RESUMO

Fluorescein isothiocyanate-dextrans (FDs) of different molecular weights were infused into corn, waxy rice, tapioca, and potato starches under atmospheric and high hydrostatic pressures (HHP). FD4, FD10, FD20, and FD40 (Mw 4000, 10,000, 20,000, and 40,000, respectively) were used as infusion materials. Confocal laser scanning microscopy confirmed that all FDs except FD40 infused into corn, waxy rice, and tapioca starches. However, no FDs infused into potato starch. Corn starch had the highest amounts of infused FDs. As molar mass increased, the amount of infused FD decreased in all starches. The infused amounts of FDs in corn starch were similar at 200-300 MPa and atmospheric pressure. Infusion of FDs at 400 MPa was reduced due to partial gelatinization. These results confirm that infusion efficiency is inversely proportional to the molecular weight of the infused material and large materials (Mw > 40,000) cannot be infused into starch granules under atmospheric pressure or HHP. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10068-021-00972-2.

9.
Foods ; 10(11)2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34829166

RESUMO

In this study, the rheological properties of several commercial rice noodle strands were investigated. In the bending test, failure stress decreased as the cooking temperature increased from 80 to 90 °C, and the cooking time increased from 3 to 4 min for higher rice content noodles (>60%). The stress-relaxation test and sensory tests were carried out with bundles of noodles to investigate correlations with the bending test. The modulus of elasticity was higher at 80 than 90 °C. However, no correlation was found between cooking temperature and the rheological properties of lower rice content noodles. In the stress relaxation test, the deviation was larger due to the empty space in the bundle. In the correlation analysis, sensory stickiness was correlated with a modulus of elasticity in the bending test. Comparing the bending and stress-relaxation tests, each instrumental variable showed differences in the rheological properties of rice noodles in strands and bundles. However, the bending test measured with noodle strands seemed to be most suitable as a method of measuring the rheological properties of rice noodles.

10.
Int J Biol Macromol ; 168: 816-822, 2021 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-33242554

RESUMO

Using restructuring technology, A- or B-type crystalline granular potato starch was produced from amorphous granular potato starch (AGPS). AGPS was prepared using ethanol-heat processing, and hydrothermal treatments were performed with different moisture contents (18, 29, 200% d.b.) and temperatures (4, 25, 40, 60, 80 °C) for 3 weeks. AGPS showed no endothermic peak in a DSC thermogram, while hydrothermally treated AGPS (HAGPS) revealed endothermic peaks. In X-ray diffraction, AGPS displayed an amorphous pattern, and HAGPS displayed A- or B-type crystalline patterns depending on treatment temperature and moisture content. Neither AGPS nor HAGPS had typical RVA pasting curves, and their viscosities gradually increased. Raman spectroscopy and FT-IR confirmed that ordered structure and crystalline regions increased in HAGPS. Resistant starch (RS) and slowly digestible starch (SDS) contents of HAGPS increased but rapidly digestible starch (RDS) content decreased compared to AGPS. These results elucidated that hydrothermal treatment could change the physicochemical properties of AGPS and produce an identical material, such as granular potato starch with A-type and B-type crystalline granular potato starch.


Assuntos
Etanol/química , Solanum tuberosum/química , Amido/química , Cristalografia por Raios X , Temperatura Alta , Hidrólise , Espectroscopia de Infravermelho com Transformada de Fourier , Viscosidade , Difração de Raios X
11.
Ann Epidemiol ; 48: 36-42.e3, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32651047

RESUMO

PURPOSE: The purpose of this study was to understand why a housing mobility experiment caused harmful effects on adolescent boys' risky behaviors. METHODS: Moving to Opportunity (MTO) (1994-2010) randomly assigned volunteer families to a treatment group receiving a Section 8 rental voucher or a public housing control group. Our outcome was a global risky behavior index (RBI; measured in 2002, n = 750 boys) measuring the fraction of 10 items the youth engaged in, 6 measuring past 30-day substance use and 4 measuring recent risky sexual behavior. Potential mediators (measured in 2002) included peer social relationships (e.g., peer drug use, peer gang membership). RESULTS: The voucher treatment main effect on boys' RBI was harmful (B (SE) = 0.05 (0.02), 95% CI 0.01, 0.08), and treatment marginally increased having friends who used drugs compared to controls (B (SE) = 0.67 (0.23), 95% CI 0.22, 1.12). Having friends who used drugs marginally mediated the MTO treatment effect on RBI (indirect effect: B (SE) = 0.02(.01), 95% CI -0.002, 0.04), reducing the total treatment effect by 39%. CONCLUSIONS: Incorporating additional supports into housing voucher programs may help support teenage boys who experience disruptions to their social networks, to buffer potential adverse consequences of residential mobility.


Assuntos
Comportamento do Adolescente/psicologia , Relações Interpessoais , Grupo Associado , Habitação Popular , Características de Residência , Comportamento Sexual/psicologia , Determinantes Sociais da Saúde/economia , Transtornos Relacionados ao Uso de Substâncias/psicologia , Adolescente , Características da Família , Humanos , Masculino , Dinâmica Populacional , Pobreza , Habitação Popular/economia , Habitação Popular/estatística & dados numéricos , Características de Residência/estatística & dados numéricos , Fatores de Risco , Assunção de Riscos , Determinantes Sociais da Saúde/estatística & dados numéricos , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Estados Unidos
12.
Food Sci Biotechnol ; 28(6): 1723-1731, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31807345

RESUMO

Physicochemical properties of acetylated (AC), cross-linked (CL), and hydroxypropylated (HP) chestnut starches were investigated. Modified chestnut starch showed low RS and amylose contents. AC revealed the highest solubility and HP showed the highest swelling power at 60 °C. CL showed the lowest solubility and swelling power at both 60 and 90 °C. AC and HP showed a lower pasting temperature and higher peak viscosity than native chestnut starch (NC). Modified chestnut starch formed gels at higher solid content than NC. CL had the lowest freeze-thaw stability, and AC and HP showed the strongest tolerance to freeze-thaw cycles. Amylopectin melting enthalpy of NC dramatically increased over the first 2 days and continued increasing gradually until day 24. On the other hand, all the modified chestnut starches showed a slight increase in amylopectin melting enthalpy, indicating retarded retrogradation. CL showed the lowest degree of retrogradation, followed by HP, AC, and NC.

13.
Food Sci Biotechnol ; 28(1): 99-102, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30815299

RESUMO

The objective of this study was to develop new drug delivery systems (DDS) and nutrient delivery systems (NDS), using starch as a carrier material for infusion technology. Corn, waxy rice, non-waxy rice, and potato starches were used as carrier materials. Sodium fluorescein was used as an infusion material for easy detection. Each starch suspension with sodium fluorescein was reacted in a water bath at 40, 50, and 60 °C for 30 min. After each reaction, the concentration of sodium fluorescein in the supernatant was measured using a fluorescence detector. Precipitated starch was observed using fluorescence microscopy. About 70% of sodium fluorescein infused in waxy rice and corn starches at 60 °C. Additionally, the granules of these two starches were luminous by green light when exposed to a fluorescence detector, suggesting that corn and waxy rice starches can be used as carrier materials in infusion technology for DDS and NDS.

14.
Carbohydr Polym ; 178: 41-47, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-29050612

RESUMO

Amorphous granular potato starch (AGPS) was prepared through heat treatment of native potato starch (NPS) at 94°C with 53% EtOH, while cross-linked amorphous granular potato starch (CLAGPS) was prepared through cross-linking of NPS with sodium trimetaphosphate/sodium tripolyphosphate (STMP/STPP, 99:1) and heat treatment. Light and polarized microscopy showed that both AGPS and CLAGPS maintained their granule shapes but lost birefringence. DSC and XRD of both AGPS and CLAGPS also revealed complete gelatinization. On the other hand, CLAGPS exhibited no RVA pasting viscosity and AGPS had a higher final viscosity than NPS or CLAGPS. AGPS had a higher RS content than gelatinized potato starch, while that of CLAGPS did not increase, despite the cross-linking modification. Thus, AGPS and CLAGPS had distinct physicochemical properties from each other and from NPS, suggesting their potential applicability to the food, textile, and paper industries.


Assuntos
Solanum tuberosum/química , Amido/química , Fenômenos Químicos , Géis , Viscosidade
15.
Food Sci Biotechnol ; 26(3): 671-678, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-30263591

RESUMO

Amorphous granular starches (AGS) and non-granular amorphous starches (non-AGS) of corn, tapioca and rice were prepared using high hydrostatic pressure (HHP) treatment with ethanol and water washing, respectively and their physicochemical properties were investigated. Water holding capacity and apparent viscosity of AGS and non-AGS were higher than those of native one in all starches. In RVA pasting properties, AGS and non-AGS showed higher pasting temperature and lower peak viscosity than those of native one. Furthermore, non-AGS showed distinctively lower peak viscosity compared to that of AGS possibly due to its non-granular structure. Apparent viscosity of non-AGS revealed relatively lower than commercial pre-gelatinized starch because of heat and pressure-induced gelatinization. Maintaining granular structure in HHP treated pre-gelatinized starch provide a distinctive physicochemical characteristics compared to native starch and preparation of gelatinized starch with different gelatinization and washing methods could cause big differences in their physicochemical properties.

16.
Soc Serv Rev ; 91(1): 41-70, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38585345

RESUMO

This article examines the factors shaping longitudinal patterns of housing insecurity in the wake of the Great Recession, with a focus on whether housing assistance helped renters who received it. We use data from the first two waves (2009-10 and 2011) of the Michigan Recession and Recovery Study, a population-representative sample of working-aged adults from Southeast Michigan. We use detailed reports from renters and other non-homeowners to construct measures of instability and cost-related housing problems at both waves, and we compare the changes in these over follow-up between housing assistance recipients and their income-eligible but non-recipient counterparts. Our findings suggest that receiving housing assistance reduced the chance of experiencing housing insecurity problems over follow-up regardless of baseline housing insecurity.

17.
Carbohydr Polym ; 146: 328-36, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27112881

RESUMO

Effect of high hydrostatic pressure (HHP) treatment on conventional hydroxypropylation of maize starch was investigated. Three groups, 'Con' group (conventional hydroxypropylation), 'HHP-Con' group (HHP treatment before conventional hydroxypropylation), and 'Con-HHP' group (HHP treatment after conventional hydroxypropylation), were used in this work. The degree of substitution (DS) increased over the reaction time in all groups. Swelling power and solubility were high in HHP treated groups compared to Con group because HHP treatment weakens the binding forces inside starch granule. In the results of RVA, the Con-HHP group showed a lower pasting temperature and a higher breakdown and viscosity than the other groups. Pre- and post HHP-treatments altered the physicochemical properties of hydroxypropylated maize starch. Hydrophilic and bulky hydroxypropyl groups may weaken the bindings in the granule, while the HHP treatment promoted the collapse of granules and accelerated the leaching of intra-soluble materials.


Assuntos
Pressão Hidrostática , Amido/química , Zea mays/química , Solubilidade , Viscosidade
18.
J Urban Health ; 90(1): 41-55, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22689295

RESUMO

The growing tension between conservative attitudes and liberal policies on gender issues in Chile is reflected by the high rates of domestic violence juxtaposed by a strong governmental policy aimed at preventing this social problem. Attempts to understand factors associated with domestic violence in Chile, and in other countries as well, have not paid much attention to neighborhood-level factors. This manuscript examined the extent to which selected neighborhood characteristics were associated with domestic violence against women. Relying on theories of social disorganization and social stress, this study conceptualized residence in a disadvantaged neighborhood as a source of stress and examined the relationship between detrimental physical and social characteristics of neighborhoods and the chance of women experiencing domestic violence. Results revealed that a higher level of trash in neighborhoods was associated with increased rates of domestic violence above and beyond individual characteristics. Findings also suggested that the relationship between high levels of trash in neighborhoods and domestic violence was greater for women with higher levels of financial stress. Given the potential role of neighborhood environments in reducing domestic violence, a comprehensive approach incorporating both neighborhood- and individual-level factors may be critical in designing effective preventive interventions for domestic violence.


Assuntos
Violência Doméstica/estatística & dados numéricos , Características de Residência/estatística & dados numéricos , Adaptação Psicológica , Consumo de Bebidas Alcoólicas , Anomia (Social) , Chile , Estudos Transversais , Violência Doméstica/prevenção & controle , Humanos , Pobreza
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