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1.
J Dairy Sci ; 104(6): 6487-6495, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33741159

RESUMO

There is increasing industrial interest in the use of the milkfat globule membrane as a food ingredient. The objective of this research was to determine whether the aerosol whipping performance of cream separated into butter and buttermilk, and then recombined, would perform in a manner similar to untreated cream. Churning of cream tempered to different solid fat contents was used to separate butter from buttermilk, which were then recombined at the same ratios as the initial extraction yield, or with 25% extra buttermilk. Differences in milkfat globule size distributions among the recombined creams were apparent; however, their whipping behavior and overrun were similar. Importantly, all recombined creams did not yield properties similar to the original cream, indicating that the unique native milkfat globule membrane structure plays a role in cream performance well beyond its simple presence.


Assuntos
Leitelho , Manipulação de Alimentos , Animais , Manteiga/análise
2.
Chaos ; 31(11): 113129, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34881579

RESUMO

Bifurcations and tipping points (TPs) are an important part of the Earth system's behavior. These critical points represent thresholds at which small changes in the system's parameters or in the forcing abruptly switch it from one state or type of behavior to another. Current concern with TPs is largely due to the potential of slow anthropogenic forcing to bring about abrupt, and possibly irreversible, change to the physical climate system and impacted ecosystems. Paleoclimate proxy records have been shown to contain abrupt transitions, or "jumps," which may represent former instances of such dramatic climate change events. These transitions can provide valuable information for identifying critical TPs in current and future climate evolution. Here, we present a robust methodology for detecting abrupt transitions in proxy records that is applied to ice core and speleothem records of the last climate cycle. This methodology is based on the nonparametric Kolmogorov-Smirnov (KS) test for the equality, or not, of the probability distributions associated with two samples drawn from a time series, before and after any potential jump. To improve the detection of abrupt transitions in proxy records, the KS test is augmented by several other criteria and it is compared with recurrence analysis. The augmented KS test results show substantial skill when compared with more subjective criteria for jump detection. This test can also usefully complement recurrence analysis and improve upon certain aspects of its results.

3.
Environ Technol ; 35(13-16): 2086-94, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24956803

RESUMO

The large area demand of constructed wetlands (CWs) is documented as a weak point that can be potentially reduced by applying active aeration. The aim of this study was, therefore, to understand the effects of aeration on the treatment performance, the biofilm activity, the protozoan population size and potential CW footprint reduction of different horizontal flow (HF) CW configurations. Two experimental periods were considered: a first period with low organic loading rate (OLR) and a second period with high OLR. Three HF CW configurations were compared: a conventional (control), an aerated and a hybrid CW (aerated followed by a non-aerated CW). The results obtained reinforced the competence of aerated CW for organic matter removal (81-89% of chemical oxygen demand) while for nitrogen elimination the control (19-24%) and hybrid (8-41%) systems performed better than the aerated system (-6% to 33%). Biofilm activity and protozoa abundance were distinctly higher at the inlet zones when compared with the outlet zones of all CWs, as well as in the aerated systems when compared with the non-aerated CWs. The protozoan abundance increased with an increase in the OLR and ciliates were found to be the dominant group. Overall, the active aeration highlighted the efficiency and stability of the CWs for organic matter removal and thus can be used as a promising tool to enhance microbial activity and grazing by protozoa; eventually reducing solid accumulation in the bed media. These beneficial effects contribute to reduce the CWs' area requirements.


Assuntos
Microbiologia da Água , Purificação da Água , Áreas Alagadas , Aerobiose , Biofilmes , Águas Residuárias/química , Águas Residuárias/microbiologia
4.
Explore (NY) ; 20(1): 54-61, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37365081

RESUMO

Individuals with trauma experience negative mental health impacts and are at risk of poor cardiovascular outcomes. Unmanaged, these conditions may worsen, compromising healing and wellbeing. Yoga, particularly trauma-informed, may improve outcomes. The current pilot study explores the impact of a novel trauma-informed yoga and mindfulness curriculum on wellbeing in two parts. The first examined mental health (stress, mood) outcomes in four trauma-impacted populations: adults who were incarcerated (INC), individuals in recovery from substance use disorders (SU), veterans (VA), and vulnerable youth (YTH) assessing both the impact of individual class participation and impact of attending at least four curriculum sessions. For the subgroup of incarcerated individuals, impact by theme was examined. After curriculum sessions, stress was reduced, and mood improved. Across multiple sessions both the largest decreases in stress and greatest increase in mood occurred after participant in the first session. Further, a specific exploration of curriculum class impact by theme for participants who were incarcerated indicated no difference in impact by theme. The second part of this study explored cardiovascular outcomes for the population of those in recovery from substance use. Reductions in systolic blood pressure occurred immediately after the first curriculum session, and diastolic blood pressure reduced over three consecutive sessions.


Assuntos
Atenção Plena , Yoga , Adulto , Adolescente , Humanos , Projetos Piloto , Afeto , Currículo
5.
Arch Pediatr ; 29(7): 484-489, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36109284

RESUMO

BACKGROUND: In child and adolescent psychiatry, many patients are placed in welfare institutions or foster care. OBJECTIVE: It is important to study their progress in the long term and to examine the psychological and social care arrangements as well as their impacts. POPULATION AND METHODS: This qualitative study designed to identify potential prognostic factors relating to the outcome of children placed in a welfare center or foster care before the age of 4 years was based on the analysis of 34 case histories of children placed in a welfare center or foster care in Angers. These records involved 129 cases collected for the "Saint Ex" study, a quantitative case study conducted from 1994 to 2001 designed to assess the outcome of children placed in a welfare center or foster care in Angers before the age of 4. The population sampling was purposive and was based on eight subgroups defined by three clinical criteria: Parent-Infant Relationship Global Scale assessment (PIR-GAS) at T1 (admission into welfare center or foster care), the status of a "infant at risk" at T1, and GAF (Global Assessment of Functioning) at T2 (exit from the welfare center or foster care). RESULTS: The study population included 11 girls and 23 boys. Factors contributing to adverse progression included problems with interactions at a very early age, failure to listen or respond to a child's request regarding his or her placement, long delays between establishing facts and implementing social measures, discontinuity and/or inconsistency regarding the placement arrangements, and sexual abuse. On the other hand, factors contributing to positive progress included the diagnosis and adapted treatment of a mental disorder in the case of one or both parents, early placement in a foster family, considering the child's requests regarding the placement, responsiveness of social services, and psychological or psychiatric follow-up. CONCLUSION: The analysis of these 34 cases sheds light on several prognostic elements, with the combination of all these factors as the background. Care based on prevention seems essential to protect early interactions and shorten the time that children are exposed to danger.


Assuntos
Maus-Tratos Infantis , Proteção da Criança , Adolescente , Criança , Maus-Tratos Infantis/diagnóstico , Maus-Tratos Infantis/psicologia , Pré-Escolar , Família , Feminino , Cuidados no Lar de Adoção , Humanos , Lactente , Masculino , Prognóstico
7.
Water Res ; 184: 116152, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32791422

RESUMO

Microalgae show great potential for wastewater treatment and nutrient recovery. However, microalgae cultivation and harvesting are affected by the low biomass concentrations which are inherent to the photoautotrophic growth process. Mixotrophic growth can be a solution as it increases microalgae biomass concentration independently from the incident light intensity. In this work, a combined respirometric-titrimetric unit was used to assess the microalgae kinetics during such mixotrophic growth conditions for Chlorella vulgaris. Based on the experimental results, a microalgae model was extended in order to gain more insight in the delicate balance between photoautotrophic and heterotrophic growth. The results suggest that during heterotrophic growth with light in absence of external inorganic carbon sources (i.e. photoheterotrophic growth), all CO2 produced by the heterotrophic pathway is internally recycled for photoautotrophic growth. Moreover, it was shown that photoautotrophic growth is the preferential growth mechanism under mixotrophic cultivation conditions (i.e. light + inorganic carbon + organic carbon), but that high oxygen concentrations activate the heterotrophic growth pathway to avoid photorespiration. The extended microalgae model supports these findings, with good model performance for all conducted experiments.


Assuntos
Chlorella vulgaris , Microalgas , Biomassa , Processos Heterotróficos , Águas Residuárias
8.
Science ; 171(3967): 170-2, 1971 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-5538826

RESUMO

The infrared spectrum of "polywater" is remarkably similar to that of sodium lactate, the primary constituent of sweat. It is proposed, therefore, that this property of "polywater," and possibly others, results from accidental biological contamination. Such contamination is consistent with chemical analyses of "polywater" samples prepared both here and abroad.


Assuntos
Polímeros/análise , Suor/análise , Água/análise , Raios Infravermelhos , Lactatos/análise , Espectrofotometria
9.
Science ; 167(3926): 1715-9, 1970 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-17729617

RESUMO

Several polywater samples were prepared by the standard methods and have the same physical and spectroscopic properties as those made in other laboratories. However, a variety of chemical analyses show high concentrations of impurities which may account for many of the anomalous properties.

10.
Science ; 220(4597): 615-7, 1983 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-6836305

RESUMO

Resonance Raman spectra of photolyzed carbonmonoxyhemoglobin obtained with 10-nanosecond pulses are compared with the spectra of photolyzed carbonmonoxyhemoglobin stabilized at 80 K. In comparing the deoxy with the photodissociated species, the changes in the Raman spectra are the same for these two experimental regimes. These results show that at ambient and cryogenic temperatures the heme pocket in liganded hemoglobin is significantly different from that of deoxyhemoglobin. It is concluded that measurements of the properties of intermediate species from photodissociated hemoglobin stabilized at low temperatures can be used to probe the short-lived metastable forms of hemoglobin present after photodissociation under biologically relevant solution conditions.


Assuntos
Hemoglobinas , Carboxihemoglobina , Fenômenos Químicos , Química , Congelamento , Humanos , Ligantes , Análise Espectral Raman , Temperatura
11.
Science ; 171(3967): 167-70, 1971 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-17751327

RESUMO

The ESCA spectra of "polywater" show that this anomalous, high-density, viscous, nonvolatile material contains high concentrations of sodium, potassium, sulfate, chloride, nitrate, borates, silicates, and carbon-oxygen compounds with trace amounts of other impurities but very little water. On the basis of this evidence, in conjunction with reported spectroscopic and analytical experiments, it is very unlikely that a polymerized form of water has been discovered.

12.
Science ; 225(4659): 329-31, 1984 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-6330890

RESUMO

The iron-carbon monoxide stretching mode and the iron-carbon-oxygen bending mode in carbon monoxide-bound cytochrome oxidase have been assigned at 520 and 578 cm-1, respectively. The frequencies, widths, and intensities of these modes show that the Fe-C-O grouping in carbon monoxide-cytochrome a3 is linear but tilted from the normal to the heme plane; that the iron-histidine bond in both five- and six-coordinate cytochrome a3 is strained; and that the carbon monoxide and the proximal histidine each have characteristic, well-defined orientations in all molecules. These data can account for the binding affinities of carbon monoxide and dioxygen under physiological conditions.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Animais , Monóxido de Carbono/metabolismo , Bovinos , Fenômenos Químicos , Química , Mioglobina/metabolismo , Oxirredução , Oxigênio/metabolismo , Análise Espectral Raman
13.
Science ; 213(4508): 657-9, 1981 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-7256263

RESUMO

A dramatic change occurs in the vibrational properties of the iron-histidine bond, trans to the oxygen binding site, on freezing deoxyhemoglobin. The large, quaternary structure-dependent differences in the shape and frequency of the iron-histidine mode observed in resonance Raman scattering measurements above freezing ae significantly diminished by the freezing event and the scattering intensity increases substantially. On further reduction in temperature to 10 K this broad line becomes narrow and shifts to a higher frequency. These data implicate dynamical processes and protein interaction with water as contributors to the quaternary structure dependence of the iron-histidine bond and thus reflect on the role of that bond in the energetics of cooperative ligand binding.


Assuntos
Congelamento , Heme , Hemoglobina A , Regulação Alostérica , Histidina , Humanos , Movimento (Física) , Conformação Proteica , Análise Espectral Raman , Água
14.
Science ; 218(4578): 1244-6, 1982 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-7146910

RESUMO

Low-frequency resonance Raman spectra of transient hemoglobin species were observed within 10 nanoseconds of photolysis. The Raman frequencies of the iron-proximal histidine stretching mode for transient species having either the R or the T quaternary structure are higher than in the corresponding deoxy species. The observed frequency difference in the iron-histidine mode between the R- and T- state transients indicates that there are quaternary structure-dependent protein forces on the iron-histidine bond in the liganded hemoglobins. These differences are interpreted in terms of changes in the tilt of the histidine with respect to the heme plane.


Assuntos
Hemoglobinas , Carboxihemoglobina , Heme , Histidina , Humanos , Ferro , Movimento (Física) , Mioglobina , Fotólise , Análise Espectral Raman
15.
Biomed Opt Express ; 10(5): 2478-2492, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31149380

RESUMO

Gliomas are diffuse and hard to cure brain tumors. A major reason for their aggressive behavior is their property to infiltrate the brain. The gross appearance of the infiltrative component is comparable to normal brain, constituting an obstacle to extended surgical resection. 5-ALA induced PpIX fluorescence measurements enable gains in sensitivity to detect infiltrated cells, but still lack sensitivity to get accurate discrimination between the tumor margin and healthy tissue. In this fluorescence spectroscopic study, we assume that two states of PpIX contribute to total fluorescence to get better discrimination of healthy tissues against tumor margins. We reveal that fluorescence in low-density margins of high-grade gliomas or in low-grade gliomas is mainly influenced by the second state of PpIX centered at 620 nm. We thus conclude that consideration of the contributions of both states to total fluorescence can help to improve fluorescence-guided resection of gliomas by discriminating healthy tissues from tumor margins.

16.
Mol Cell Biol ; 18(7): 4272-81, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9632811

RESUMO

In glial C6 cells constitutively expressing wild-type p53, synthesis of the calcium-binding protein S100B is associated with cell density-dependent inhibition of growth and apoptosis in response to UV irradiation. A functional interaction between S100B and p53 was first demonstrated in p53-negative mouse embryo fibroblasts (MEF cells) by sequential transfection with the S100B and the temperature-sensitive p53Val135 genes. We show that in MEF cells expressing a low level of p53Val135, S100B cooperates with p53Val135 in triggering calcium-dependent cell growth arrest and cell death in response to UV irradiation at the nonpermissive temperature (37.5 degreesC). Calcium-dependent growth arrest of MEF cells expressing S100B correlates with specific nuclear accumulation of the wild-type p53Val135 conformational species. S100B modulation of wild-type p53Val135 nuclear translocation and functions was confirmed with the rat embryo fibroblast (REF) cell line clone 6, which is transformed by oncogenic Ha-ras and overexpression of p53Val135. Ectopic expression of S100B in clone 6 cells restores contact inhibition of growth at 37.5 degreesC, which also correlates with nuclear accumulation of the wild-type p53Val135 conformational species. Moreover, a calcium ionophore mediates a reversible G1 arrest in S100B-expressing REF (S100B-REF) cells at 37.5 degreesC that is phenotypically indistinguishable from p53-mediated G1 arrest at the permissive temperature (32 degreesC). S100B-REF cells proceeding from G1 underwent apoptosis in response to UV irradiation. Our data support a model in which calcium signaling and S100B cooperate with the p53 pathways of cell growth inhibition and apoptosis.


Assuntos
Apoptose , Proteínas de Ligação ao Cálcio/biossíntese , Cálcio/metabolismo , Divisão Celular , Fatores de Crescimento Neural/biossíntese , Proteínas S100 , Proteína Supressora de Tumor p53/metabolismo , Animais , Apoptose/efeitos da radiação , Proteínas de Ligação ao Cálcio/genética , Linhagem Celular , Núcleo Celular , Fase G1 , Humanos , Camundongos , Fatores de Crescimento Neural/genética , Ratos , Subunidade beta da Proteína Ligante de Cálcio S100 , Transdução de Sinais , Temperatura , Transfecção , Proteína Supressora de Tumor p53/genética , Raios Ultravioleta , Valina/genética
17.
Sci Total Environ ; 380(1-3): 102-15, 2007 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-17240426

RESUMO

This study assessed the accumulation of metals in a horizontal subsurface flow constructed wetland treating domestic wastewater of 350 PE after three years of operation. Metal concentrations in the influent wastewater, effluent, sediment, leaves, stems, and belowground biomass of Phragmites australis were analysed. Spatial variations were assessed by sampling at increasing distance from the inlet and at different positions across the width of the reed bed. All metals except Fe and Mn were efficiently removed in the CW, total metal concentrations in the effluent complied with basic environmental quality standards for surface water, and dissolved metal concentrations were often lower than analytical detection limits. Removal efficiencies varied between 49% for Ni and 93% for Al. Export of dissolved Mn and particulate Fe occurred, probably related to redox conditions in the sediment. After 3 years of operation, the sediment in the inlet area was significantly contaminated with Zn, Cu, and Cd, whereas Pb could form a contamination problem within the near future. The Cr and Ni levels in the sediment were low throughout the entire reed bed. At this stage of operation, the contamination problem was still situated within the inlet area and metal concentrations in the sediment decreased towards background values further along the treatment path. An exponential decrease of the metal mass in the sediment and belowground biomass was seen for all metals except Mn. Contrary to the other metals, Mn concentrations in the sediment increased with distance. For all metals, less than 2% of the mass removed from the wastewater after passage through the reed bed is accumulated in the aboveground reed biomass. The sediment acts as the primary sink for metals.


Assuntos
Metais Pesados/análise , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise , Poluição da Água/análise , Áreas Alagadas , Bélgica , Biomassa , Monitoramento Ambiental , Sedimentos Geológicos/química , Metais Pesados/metabolismo , Estruturas Vegetais/química , Estruturas Vegetais/metabolismo , Poaceae/química , Poaceae/metabolismo , Eliminação de Resíduos Líquidos/instrumentação , Movimentos da Água , Poluentes Químicos da Água/metabolismo , Poluição da Água/prevenção & controle
18.
Water Sci Technol ; 56(3): 193-8, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17802855

RESUMO

The removal of Co, Ni, Cu and Zn from synthetic industrial wastewater was studied in subsurface flow constructed wetland microcosms filled with gravel or a gravel/straw mixture. Half of the microcosms were planted with Phragmites australis and half were left unplanted. All microcosms received low-strength wastewater (1 mg L(-1) of Co, Ni, and Zn, 0.5 mg L(-1) Cu, 2,000mg L(-1) SO4) during seven 14-day incubation batches. The pore water was regularly monitored at two depths for heavy metals, sulphate, organic carbon and redox potential. Sorption properties of gravel and straw were assessed in a separate experiment. A second series of seven incubation batches with high-strength wastewater (10 mg L(-1) of each metal, 2,000 mg L(-1) SO4) was then applied to saturate the substrate. Glucose was added to the gravel microcosms together with the high-strength wastewater. Sorption processes were responsible for metal removal during start-up, with the highest removal efficiencies in the gravel microcosms. The lower initial efficiencies in the gravel/straw microcosms were presumably caused by the decomposition of straw. However, after establishment of anaerobic conditions (Eh approximately -200 mV), precipitation as metal sulphides provided an additional removal pathway in the gravel/straw microcosms. The addition of glucose to gravel microcosms enhanced sulphate reduction and metal removal, although Phragmites australis negatively affected these processes in the top-layer of all microcosms.


Assuntos
Biodegradação Ambiental , Metais Pesados/isolamento & purificação , Sulfatos/química , Purificação da Água/métodos , Áreas Alagadas , Adsorção , Eliminação de Resíduos Líquidos , Movimentos da Água
19.
J Colloid Interface Sci ; 302(2): 537-46, 2006 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-16928380

RESUMO

The size and structural characteristics of polyacrylamide-based water-soluble microgel dispersions were investigated by optical and rheological methods. Microgel hydrodynamic radii Rh were measured by light scattering and derived from intrinsic shear viscosity [eta]0. The variations of Rh3 and [eta]0 with the crosslink density Nx, follow the scaling law Rh3 congruent withNx(-alpha) with alpha close to 0.63, in good agreement with the simple structural model proposed in this paper showing how the exact value of alpha depends on inner structural details of the microgel. The plateau viscosity versus particle apparent volume fraction shows a monotonous change from hard sphere dispersions (high crosslink density of microgels) to flexible linear polymer solutions. Measurements of the first normal stress difference N1 show that increasing the microgel crosslink density affects the system viscosity more than its elasticity. Under oscillatory shear flow, loss and storage moduli undergo both qualitative and quantitative changes with crosslink density. At moderate concentrations, the elastic modulus is the most affected and its slope in low frequency regime decreases from two to less than one as Nx increases. We discuss the experimental results within the frame of knowledge on linear, branched polymer solutions and soft microgel suspensions.


Assuntos
Resinas Acrílicas/química , Géis/química , Óptica e Fotônica , Tamanho da Partícula , Reologia , Solubilidade , Propriedades de Superfície , Água/química
20.
Int J Biol Macromol ; 38(1): 40-4, 2006 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-16443267

RESUMO

The physical properties and microstructure of gelatin-maltodextrin hydrogels fixed with genipin (GP) were investigated as a function of pH (3-7), maltodextrin (MD) (0-9%, w/w) and GP (0-10 mM levels), at a constant gelatin (G) concentration (10%, w/w). Network strength (elastic modulus, E) and swelling behavior were characterized by large deformation testing and by swelling index (SI). In general, network strength increased and swelling decreased at higher pH, MD and GP levels, except at pH 3, where E was independent of the GP concentration until approximately 7.5 mM, above which it declined. Confocal scanning laser microscopy (CLSM) images showed phase separation to be suppressed at pH 3, whereas at pH 7, separation into a self-similar dispersed phase was apparent. Overall, the judicious use of GP to crosslink G was an appropriate means of kinetically trapping MD within the gelatin network.


Assuntos
Gelatina/química , Polissacarídeos/química , Piranos/química , Animais , Fenômenos Químicos , Físico-Química , Hidrogéis , Técnicas In Vitro , Glicosídeos Iridoides , Iridoides , Microscopia Confocal , Estrutura Molecular , Suínos
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