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1.
Science ; 178(4061): 623-5, 1972 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-5086396

RESUMO

There was decreased synthesis of the beta-globin chain in the peripheral blood, and equal synthesis of alpha- and non-alpha-chains in the bone marrow of three patients with hemoglobin Lepore trait, similar to the findings in patients with heterozygous beta-thalassemia. There is a relative instability of the synthetic mechanism for normal beta-chain in these patients.


Assuntos
Medula Óssea/metabolismo , Globinas/biossíntese , Hemoglobinopatias/metabolismo , Isótopos de Carbono , Cromatografia , Globinas/análise , Hemoglobinopatias/sangue , Humanos , Leucina/metabolismo , Talassemia/metabolismo
2.
Environ Technol ; 29(7): 797-806, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18697521

RESUMO

In previous work, synthetic urine was used as a readily available proxy for real urine for determining the factors which affect the recovery of struvite from urine. Based on these findings with synthetic urine, we recovered struvite from real urine and, thus, showed that a) the synthetic urine served as an adequate model for determining the processes which affect struvite precipitation, and b) high quality struvite can be recovered from real human urine. For urine solutions diluted up to four times, an average of 23% of phosphorus and 80% of magnesium was precipitated naturally; the remaining supernatant was then dosed with magnesium to recover the phosphorus still in solution. The struvite recovered was approximately 99% pure regardless of storage conditions although full strength urine was best for struvite recovery since it contains the greatest mass of harvestable phosphorus. We conclude that synthetic urine can be used as a proxy for real urine when investigating struvite recovery provided the synthetic mixture is consistent with the expected composition in the specific context.


Assuntos
Compostos de Magnésio/urina , Fosfatos/urina , Amônia/análise , Cálcio/isolamento & purificação , Humanos , Concentração de Íons de Hidrogênio , Estruvita
3.
Environ Technol ; 29(7): 807-16, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18697522

RESUMO

In laboratory experiments using synthetic urine the effect of temperature, faecal contamination, dilution and headspace on urine to be used as a feedstock for struvite recovery were examined. The effects of adding different quantities of magnesium on the amount of phosphorus that could be removed from solution was also examined. An average of 62% of phosphorus could be removed in the form of struvite when magnesium was added to the urine solution after ureolysis had forced the precipitation of calcium and magnesium minerals. Dilution and the presence of faecal urease were found to affect the rate of ureolysis but not the purity of the struvite recovered. These results indicate that, by simply storing urine until it achieves a pH of 8 or greater, struvite can be recovered from source-separated urine with only a magnesium addition.


Assuntos
Fósforo/urina , Humanos , Temperatura
4.
J Clin Invest ; 51(2): 412-8, 1972 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-5061833

RESUMO

In Italian and Chinese patients with the alpha-thalassemia syndromes the production of alpha-chain of normal hemoglobin is decreased relative to that of beta-chain in reticulocytes. In this study the relative rates of alpha- and beta-chain synthesis were determined in members of three Negro families with alpha-thalassemia. Two of the families had members with hemoglobin H disease and alpha-thalassemia trait, while the mother of several children with alpha-thalassemia trait in the third family was doubly heterozygous for alpha-thalassemia and an alpha-chain mutant. The alpha/beta ratios of globin synthesis in the patients with hemoglobin H disease and alpha-thalassemia trait indicated less severe biochemical defects in the peripheral blood than those previously determined in Italian and Chinese patients. In the third family, there was a heterogeneity of expression of the gene for alpha-thalassemia, including patients with normal red cell indices and synthesis ratios. These findings differ from those previously described in patients with alpha-thalassemia from other racial groups. Hydrops fetalis due to homozygous alpha-thalassemia may not occur in the Negro because of the relatively mild thalassemic defect.


Assuntos
Hemoglobinas Anormais/biossíntese , Talassemia/genética , Adolescente , Adulto , Negro ou Afro-Americano , Idoso , Eletroforese das Proteínas Sanguíneas , Criança , Pré-Escolar , Edema/genética , Feminino , Doenças Fetais/genética , Globinas/biossíntese , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Gravidez , Talassemia/metabolismo , Estados Unidos
5.
Am J Clin Pathol ; 75(6): 843-6, 1981 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6167160

RESUMO

An American black family in whom hemoglobin J Baltimore and beta (+)-thalassemia genes coexisted is described. The proposita is a 23-year-old woman with a hemoglobin (Hb) level of 11.5 g/dl, microcytic, hypochromic indices, increased values of Hbs A2 and F, and alpha/non-alpha synthetic ratio of 1.52. Hbs A and J Baltimore (beta 16 Gly---Asp) constituted 12% and 81.3%, respectively, of her total hemoglobin. Her sister had a very similar peripheral blood picture, but Hbs A and J Baltimore constituted 6.8% and 85.5%, respectively, of her total hemoglobin, and the alpha/non-alpha synthetic ratio was 1.39. The mother had beta(+)-thalassemia trait only, a moderate degree of anemia, and greater synthetic imbalance (alpha/non-alpha raio of 1.73). These findings suggest that the presence of the Hb J Baltimore gene ameliorates the effects of a coexistent beta-thalassemia gene.


Assuntos
Globinas/biossíntese , Hemoglobina J/biossíntese , Hemoglobinas Anormais/biossíntese , Talassemia/sangue , Adulto , Feminino , Hemoglobina Fetal/análise , Globinas/genética , Hematócrito , Hemoglobina A/análise , Hemoglobina J/genética , Humanos , Talassemia/genética
6.
Am J Clin Pathol ; 70(1): 85-8, 1978 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-696677

RESUMO

The ease of denaturation by shaking of a solution of oxyhemoglobin S (oxy-Hb S) forms the basis for a simple and reliable test for confirmation or rapid detection of Hb S in children and adults. Comparison of results of this test with those from agar gel electrophoresis in capillary blood samples from 187 black neonates at 2 to 7 days of life showed no overlap of the amounts of hemoglobin precipitated between the group of neonates with Hb S (5.7--12.0%) and that without Hb S (0--4.7%). These results indicate that the shaking test, by virtue of being simple, reliable and inexpensive, may be used to detect and confirm Hb S in large numbers of neonates before their discharge from the nursery.


Assuntos
Hemoglobina Falciforme/isolamento & purificação , Anemia Falciforme/diagnóstico , Eletroforese em Gel de Ágar , Humanos , Recém-Nascido , Doenças do Recém-Nascido/diagnóstico , Oxiemoglobinas , Espectrofotometria
7.
Ann N Y Acad Sci ; 344: 62-72, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-6930883

RESUMO

The findings presented for these two families help to explain the inheritance of alpha thalassemia, alpha-chain variants, and the relative expression of alpha genes. An 18.0-kb EcoRI fragment contains only one functional alpha gene, whereas a 20.5-kb fragment contains two. Individuals homozygous for the 18.0-kb EcoRI fragment also lack the 4.1-kb HindIII fragment that normally connects the centers of the duplicated alpha genes. These findings are consistent with a deletion involving the 5' alpha-gene locus. Presence of alpha G-Philadelphia in both families was found in association with the 18.0-kb EcoRI fragment; this short fragment was also found in an individual with alpha A. Inheritance of alpha G-Philadelphia at one alpha-gene locus was therefore also linked to the inheritance of alpha thalassemia due to a deletion involving the second alpha gene. The high percentage (46% to 48%) of alpha G found in some family members was due to alpha-thalassemia trait, or deletion of two alpha genes (-alpha G/-alpha); others with levels of variant of 32% to 34% were shown to have three functional alpha genes (-alpha G/alpha alpha). The genetic expression of the four normal alpha genes therefore appears to be equal and furthermore implies the existence of separate independently functioning transcriptional units for each of these genes in humans. It would be interesting to analyze the alpha genes in Afro-Americans reported to have alpha G-Philadelphia in the 20% to 25% range to determine whether the inheritance of alpha G can be linked to a normal alpha gene.


Assuntos
Cromossomos Humanos 21-22 e Y , Hemoglobinas/genética , Talassemia/genética , Sequência de Bases , Deleção Cromossômica , Mapeamento Cromossômico , DNA/genética , Volume de Eritrócitos , Feminino , Variação Genética , Heterozigoto , Humanos , Masculino , Linhagem , Talassemia/sangue , Transcrição Gênica
8.
Clin Chim Acta ; 100(1): 1-6, 1980 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-7351073

RESUMO

A 21-year-old American black female with mild anemia was found to be triply heterozygous for alpha-thalassemia-2, hemoglobin S and hemoglobin G Philadelphia. Hemoglobin A comprised 39% of her total hemoglobin. The alpha-thalassemia gene was expressed by an alpha/non-alpha synthesis of ratio of 0.79 +/- 0.09 and was equally unbalanced in the peripheral blood and the bone marrow. Globin synthesis studies indicated that the percentage of Hb G and Hb S in the peripheral blood is about 32% and 31% respectively. These values are due to the coexistent alpha-thalassemia-2 gene with the following most likely genotype: --alpha G/alpha alpha, beta A/beta S (or --alpha/alpha G alpha, beta A beta S).


Assuntos
População Negra , Globinas/biossíntese , Hemoglobinas Anormais/genética , Heterozigoto , Talassemia/sangue , Adulto , Cromatografia , Feminino , Hemoglobina Falciforme/genética , Humanos , Leucina/metabolismo , Fatores de Tempo , Estados Unidos
9.
Biotechnol Prog ; 17(5): 847-51, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11587573

RESUMO

Novel methods and apparatus that employ the rapid heating characteristics of microwave irradiation to facilitate the aseptic transfer of nutrients, products, and other materials between microbially sensitive systems and the external environment are described. The microwave-sterilizable access port (MSAP) consists of a 600-W magnetron emitting at a frequency of 2.45 GHz, a sterilization chamber with inlet and outlet flow lines, and a specimen transfer interface. Energy is routed to the sterilization chamber via a coaxial transmission line where small quantities of water couple strongly with the incident radiation to produce a superheated vapor phase. The efficiency of energy transfer is enhanced through the use of microwave susceptors within the sterilization chamber. Mating surfaces are thermally sterilized through direct contact with the hot gas. Efficacy has been demonstrated using the thermophile Bacillus stearothermophilus.


Assuntos
Reatores Biológicos/normas , Contaminação de Equipamentos/prevenção & controle , Micro-Ondas , Esterilização/métodos , Reatores Biológicos/microbiologia , Geobacillus stearothermophilus/patogenicidade , Vapor , Esterilização/instrumentação , Temperatura , Fatores de Tempo
10.
Am Psychol ; 47(11): 1464-74, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1482007

RESUMO

Application of Skinner's principles to socially significant human behavior had been well articulated by 1968 (Baer, Wolf, & Risley, 1968). Applications of these principles by Baer, Wolf, Risley, Hall, Hart, Christophersen, and their colleagues were in evidence as early as 1964 in the homes, schools, and clinics of inner-city Kansas City, Kansas, at the Juniper Gardens Housing Project. The work continues relatively uninterrupted, having contributed extensively to the literature of applied behavior analysis and the lives of community residents. This article describes the project and illustrates how applied behavioral research was initiated and extended, how the work addressed general concerns in psychology, and how it continues to address contemporary concerns within the community.


Assuntos
Terapia Comportamental , Serviços de Saúde da Criança/tendências , Serviços de Saúde Comunitária/tendências , Desenvolvimento de Programas , Behaviorismo , Criança , Humanos , Kansas
11.
J Exp Psychol Learn Mem Cogn ; 16(1): 98-109, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2136753

RESUMO

In four studies, 3-, 6-, and 9-month-old human infants were tested in a discrimination learning task in which visual fixation to a particular stimulus or lateral position was reinforced with an auditory stimulus. In Experiment 1, all age groups exhibited acquisition, extinction, and reinstatement of fixation to the reinforced target or position. Experiment 2 revealed that 3-month-olds retained the positional discrimination but not the stimulus discrimination after a 5-min delay between acquisition and extinction; older infants retained both types of discriminations. In Experiments 3 and 4 we investigated a possible developmental shift in the dominance of positional versus stimulus cues by training infants on displays in which stimulus and position were confounded and then by dissociating the cues on test trials. Results from both experiments indicated positional cue dominance for young infants and stimulus cue dominance for older infants. The findings are discussed in terms of differences in the attentional demands elicited by proprioceptive versus exteroceptive cues.


Assuntos
Sinais (Psicologia) , Aprendizagem por Discriminação , Psicologia da Criança , Atenção , Desenvolvimento Infantil , Fixação Ocular , Humanos , Lactente , Memória , Propriocepção , Percepção Espacial
12.
Carbohydr Res ; 327(3): 219-21, 2000 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-10945672

RESUMO

Complex permittivities (epsilon*) for microwave radiation between 0.5 and 26 GHz have been determined for alpha-, beta-, and gamma-cyclodextrins in the solid state at room temperature. For the real component of epsilon*, maxima occur near 0.6 GHz, and the relation beta > alpha > gamma is evident across the full-frequency spectrum. Dielectric loss is significant only between 5 and 12 GHz for beta- and gamma-cyclodextrins with maxima near 7.5 GHz.


Assuntos
Ciclodextrinas/efeitos da radiação , Micro-Ondas , alfa-Ciclodextrinas , beta-Ciclodextrinas , gama-Ciclodextrinas , Ciclodextrinas/química , Relação Estrutura-Atividade
13.
Microchem J ; 59(3): 372-82, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11541740

RESUMO

Flow injection analysis instrumentation and methodology for the determination of ammonia and ammonium ions in an aqueous solution are described. Using in-line solid phase basification beds containing crystalline media. the speciation of ammoniacal nitrogen is shifted toward the un-ionized form. which diffuses in the gas phase across a hydrophobic microporous hollow fiber membrane into a pure-water-containing analytical stream. The two streams flow in a countercurrent configuration on opposite sides of the membrane. The neutral pH of the analytical stream promotes the formation of ammonium cations, which are detected using specific conductance. The methodology provides a lower limit of detection of 10 microgram/L and a dynamic concentration range spanning three orders of magnitude using a 315-microliters sample injection volume. Using immobilized urease to enzymatically promote the hydrolysis of urea to produce ammonia and carbon dioxide, the technique has been extended to the determination of urea.


Assuntos
Amônia/análise , Cloreto de Amônio/química , Análise de Injeção de Fluxo/métodos , Ureia/análise , Urease/química , Cloreto de Amônio/análise , Análise de Injeção de Fluxo/instrumentação , Concentração de Íons de Hidrogênio , Hidrólise , Óxido de Magnésio , Membranas Artificiais , Esgotos , Espectrofotometria , Temperatura
14.
J Air Waste Manag Assoc ; 51(9): 1318-31, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11575885

RESUMO

The implementation of a risk-based corrective action approach often requires consideration of soil vapor migration into buildings and potential inhalation exposure and risk to human health. Due to the uncertainty associated with models for this pathway, there may be a desire to analyze indoor air samples to validate model predictions, and this approach is followed on a somewhat frequent basis at sites where risks are considered potentially significant. Indoor air testing can be problematic for a number of reasons. Soil vapor intrusion into buildings is complex, highly dependent on site-specific conditions, and may vary over time, complicating the interpretation of indoor air measurements when the goal is to deduce the subsurface-derived component. An extensive survey of indoor air quality data sets highlights the variability in indoor volatile organic compound (VOC) concentrations and numerous sources that can lead to elevated VOC levels. The contribution from soil vapor is likely to be small relative to VOCs from other sources for most sites. In light of these challenges, we discuss how studies that use indoor air testing to assess subsurface risks could be improved. To provide added perspective, we conclude by comparing indoor air concentrations and risks arising from subsurface VOCs, predicted using standard model equations for soil vapor fate and intrusion into buildings, to those associated with indoor sources.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Monitoramento Ambiental/métodos , Modelos Teóricos , Poluentes do Solo/metabolismo , Biodegradação Ambiental , Humanos , Fatores de Risco , Poluentes do Solo/análise , Volatilização
15.
Adv Space Res ; 34(7): 1494-8, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15846878

RESUMO

The conversion of solid waste into useful resources in support of long duration manned missions in space presents serious technological challenges. Several technologies, including supercritical water oxidation, microwave powered combustion and fluidized bed incineration, have been tested for the conversion of solid waste. However, none of these technologies are compatible with microgravity or hypogravity operating conditions. In this paper, we present the gradient magnetically assisted fluidized bed (G-MAFB) as a promising operating platform for fluidized bed operations in the space environment. Our experimental and theoretical work has resulted in both the development of a theoretical model based on fundamental principles for the design of the G-MAFB, and also the practical implementation of the G-MAFB in the filtration and destruction of solid biomass waste particles from liquid streams.


Assuntos
Magnetismo , Voo Espacial/instrumentação , Gerenciamento de Resíduos/métodos , Ausência de Peso , Biomassa , Desenho de Equipamento , Filtração/métodos , Gravitação , Modelos Teóricos , Gerenciamento de Resíduos/instrumentação
16.
Except Child ; 58(2): 136-45, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1836181

RESUMO

This article addresses the transition of young children from preschool programs that provide special education services to kindergarten or alternative elementary school placements. The roles of the child, family, and service providers in transition preparation, planning, implementation, and evaluation are described. Successful transitions include assessments of children's skills in meeting the demands of kindergarten programs, teaching these skills to children, and actively encouraging parent participation in plans and programs. Barriers to successful transitions include lack of time and funding to coordinate both parent activities and between-school arrangements. A critical area for future research is the long-term evaluation of the procedures described as "best practice," as well as the definition of what constitutes a successful transition.


Assuntos
Pessoas com Deficiência/educação , Acontecimentos que Mudam a Vida , Inclusão Escolar , Pré-Escolar , Família , Humanos , Ensino , Estados Unidos
17.
J Appl Behav Anal ; 21(2): 157-67, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3417579

RESUMO

This study presents a methodology for collecting detailed naturalistic data on preschool teachers' instructions and children's compliance and a descriptive analysis of variables related to instruction rate and compliance probability. In preschools, teachers and children were observed across a variety of classroom activities. Kindergarten and first-grade teachers also were observed to permit a comparison of instructional behavior between preschool and early elementary settings. Among teachers, instructions varied in frequency but displayed consistencies in form. For example, teachers more often phrased instructions as imperatives than as questions or declaratives and directed more instructions to individuals than to groups. Teachers' instructional behavior varied across preschool activities and between preschool and elementary grades. Children's compliance was related to the context of an instruction, but not to its form. In addition to providing information about naturally occurring instructional events, the results illustrate the effects of context on teacher and child behavior and suggest directions for future descriptive and experimental research.


Assuntos
Comportamento Cooperativo , Ensino/métodos , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Reforço Verbal , Comportamento Social
18.
J Appl Behav Anal ; 15(1): 1-16, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-7096223

RESUMO

Juvenile crime is a serious problem for which treatment approach has been found to be reliably effective. This outcome evaluation assessed during and posttreatment effectiveness of Teaching-Family group home treatment programs for juvenile offenders. The evaluation included the original Achievement Place program, which was the prototype for the development of the Teaching-Family treatment approach, 12 replications of Achievement Place, and 9 comparison group home programs. Primary dependent measures were retrieved from court and police files and included number of alleged offenses, percentage of youths involved in those alleged offenses, and percentage of youths institutionalized. Other dependent measures were subjective ratings of effectiveness obtained from the program consumers, including the group home residents. The results showed difference during treatment favoring the Teaching-Family programs on rate of alleged criminal offenses, percentage of youths involved in those offenses, and consumer ratings of the programs. The consumer ratings provided by the youths and their school teachers were found to be inversely and significantly correlated with the reduction of criminal offenses during treatment. There were no significant differences during treatment on measures of noncriminal offenses (e.g., truancy, runaway, and curfew violations). In the posttreatment year, none of the differences between the groups was significant on any of the outcome measures. The results are discussed in terms of measurement and design issues in the evaluation of delinquency treatment programs and in relation to the evaluation; of Teaching-Family group homes by Richard Jones and his colleagues.


Assuntos
Logro , Casas para Recuperação , Capacitação em Serviço , Delinquência Juvenil/reabilitação , Adolescente , Comportamento do Consumidor , Estudos de Avaliação como Assunto , Humanos , Delinquência Juvenil/psicologia , Reforço por Recompensa
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