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1.
Waste Manag ; 57: 226-234, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26783101

RESUMO

The possibilities and limits of pyrolysis as a means of recycling plastic rich fractions derived from discarded phones have been studied. Two plastic rich samples (⩾80wt% plastics) derived from landline and mobile phones provided by a Spanish recycling company, have been pyrolysed under N2 in a 3.5dm3 reactor at 500°C for 30min. The landline and mobile phones yielded 58 and 54.5wt% liquids, 16.7 and 12.6wt% gases and 28.3 and 32.4wt% solids respectively. The liquids were a complex mixture of organic products containing valuable chemicals (toluene, styrene, ethyl-benzene, etc.) and with high HHVs (34-38MJkg-1). The solids were composed of metals (mainly Cu, Zn, and Al) and char (≈50wt%). The gases consisted mainly of hydrocarbons and some CO, CO2 and H2. The halogens (Cl, Br) of the original samples were mainly distributed between the gases and solids. The metals and char can be easily separated and the formers may be recycled, but the uses of the char will be restricted due to its Cl/Br content. The gases may provide the energy requirements of the processing plant, but HBr and HCl must be firstly eliminated. The liquids could have a potential use as energy or chemicals source, but the practical implementation of these applications will be no exempt of great problems that may become insurmountable (difficulty of economically recovering pure chemicals, contamination by volatile metals, etc.).


Assuntos
Telefone Celular , Resíduo Eletrônico , Plásticos , Reciclagem/métodos , Bromo , Cloro , Gases , Mercúrio
2.
Water Sci Technol ; 51(10): 311-6, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16104435

RESUMO

A sequencing batch reactor (SBR) treating the effluent of a motorway service station in the south of England situated on a major tourist route was investigated. Wastewater from the kitchens, toilets and washrooms facilities was collected from the areas on each side of the motorway for treatment on-site. The SBR was designed for a population equivalent (p.e.) of 500, assuming an average flow of 100 m3/d, influent biochemical oxygen demand (BOD) of 300 mg/l, and influent suspended solids (SS) of 300 mg/l. Influent monitoring over 8 weeks revealed that the average flow was only 65 m3/d and the average influent BOD and SS were 480 mg/l and 473 mg/l respectively. This corresponded to a high sludge loading rate (F:M) of 0.42 d(-1) which accounted for poor performance. Therefore the cycle times were extended from 6 h to 7 h and effluent BOD improved from 79 to 27 mg/l.


Assuntos
Reatores Biológicos , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Culinária , Oxigênio/análise , Oxigênio/metabolismo , Recreação , Banheiros
3.
Eur J Endocrinol ; 143(5): 711-4, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11078997

RESUMO

OBJECTIVE: Leptin is an adipocyte-secreted hormone acting as a signal to the central nervous system, where it regulates energy homeostasis and neuroendocrine processes. Leptin plasma levels are mainly regulated by the percentage of body fat, but are also controlled by several metabolic and nutritional variables. Data regarding leptin secretion suggest that it is gender regulated, and higher levels are present in women than men; however, the biological basis for this sex-related difference is unknown. To clarify those points, a systematic study with tissue cultures from human omental adipose tissue was performed. DESIGN AND METHODS: Surgically obtained samples from 137 patients (68 women, 69 men) were evaluated. The assay was standardized in periods of 24 h ending at 96 h. Each adipose tissue sample from a single donor was incubated in triplicate and leptin results expressed as the mean of the integrated secretion into the medium (nanograms of leptin/g tissue per time). RESULTS: Tissue adipose cultures showed a steady leptin secretion throughout the 96 h studied, with the peak of secretory activity reached at 48 h; afterwards, the in vitro secretion reached a plateau state. Spontaneous leptin secretion in the 24 h and 48 h period, as well as the area under the curve analyzed in the 0-48 h period, showed a gender-based difference that was significantly (P<0. 05) higher in women than in men. When data of spontaneous leptin secretion were correlated with the body mass index (BMI) of the donors, no correlation was found. This suggests that in vivo leptin levels are dependent on the total amount of fat of the individual, but independent of the leptin secretory rate by the adipose tissue of the donor. CONCLUSIONS: Leptin secretion from omental adipose tissue in vitro is: (i) significantly higher in samples from women than in samples from men; and (ii) not correlated with the BMI, showing that in vitro leptin secretion is not related to the adiposity of the donor.


Assuntos
Tecido Adiposo/metabolismo , Índice de Massa Corporal , Leptina/metabolismo , Adulto , Idoso , Feminino , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Omento , Caracteres Sexuais
4.
Plant Dis ; 81(2): 204-210, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30870898

RESUMO

A rapid assay to determine antifungal activity in plant extracts and essential oils is described. Wells in microtiter plates were loaded with Botrytis cinerea spores and plant extracts or essential oils. Subsequent changes in optical density following spore germination in the wells was measured after 24 h using an automatic microtiter plate reader driven by a software program developed for this purpose. Extracts from 345 plants and 49 essential oils were evaluated for their antifungal activity against B. cinerea. Among 345 plant extracts analyzed, 13 showed high levels of antifungal activity, with species of Allium and Capsicum predominating. Among the 49 essential oils tested, palmarosa (Cymbopogon martini), red thyme (Thymus zygis), cinnamon leaf (Cinnamomum zeylanicum), and clove buds (Eugenia caryophyllata) demonstrated the most antifungal activity against B. cinerea. The most frequently occurring constituents in essential oils showing high antifungal activity were: D-limonene, cineole; ß-myrcene; α-pinene, ß-pinene; and camphor.

9.
J Perinat Med ; 16(5-6): 453-8, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3071603

RESUMO

A group of 98 third trimester pregnant women whose ultrasonographic studies raised the suspicion of intrauterine fetal growth retardation was studied. The patients were randomly assigned to two groups: Group A (Treatment group: 44 patients) and Group B (Control group: 54 patients). All patients were admitted to the hospital upon diagnosis for baseline evaluation. Those in Group A remained in the hospital until delivery (mean stay 15 +/- 5 days) and received treatment with 10 mg/t.i.d. of p.o. ritodrine. Group B patients were discharged after an average stay of 7 +/- 3 days. This group was not treated with ritodrine, and they were seen weekly in an outpatient setting. The prevalence of low-birth-weight infants for their gestational age was 47.73% in the treatment group and 40.74% in the control group. Of the deliveries in the treatment group, 40.9% were induced (half for fetal indications). In the control group 35.18% of the induced labors was (47.35% for fetal indications). Of the cases in the treatment group 18.18% were delivered by cesarean section, of which 62.5% were performed for fetal distress. The control group showed similar figures: 16.66% cesarean sections with 77.7% of them done for fetal distress. We observed an incidence of 20.45% of acute fetal distress in the study group against 12.96% in the control group. Such a difference is not statistically significant. The group under study demonstrated a rate of 6.82% pathological pH value in the umbilical artery, while the rate of abnormal values in the control group was 18.52%. In both groups, the greatest percentage of acidotic pH was observed in patients with IGR.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Retardo do Crescimento Fetal/terapia , Hospitalização , Tempo de Internação , Cuidado Pré-Natal , Ritodrina/uso terapêutico , Feminino , Retardo do Crescimento Fetal/etiologia , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Gravidez , Terceiro Trimestre da Gravidez , Estudos Prospectivos , Distribuição Aleatória , Ultrassonografia
10.
Appl Microbiol ; 18(6): 1050-6, 1969 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-5370658

RESUMO

Seventy-three N,N-disubstituted amides of long-chain, principally C(18), fatty acids were screened for antimicrobial activity against bacteria, yeasts, and molds. Amides containing an epoxy group exhibit a broad spectrum of antimicrobial activity which is further enhanced by unsaturation. Mono-unsaturation alone does not contribute a broad level of activity to the N,N-disubstituted amides of the C(18) fatty acids.


Assuntos
Amidas/farmacologia , Anti-Infecciosos/farmacologia , Ácidos Graxos/farmacologia , Antibacterianos , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos
11.
Rev Med Chil ; 129(2): 166-72, 2001 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-11351468

RESUMO

BACKGROUND: Acute Mountain Sickness (AMS) refers to signs and symptoms associated with hypobaric hypoxia. Its reported incidence is highly variable. AIM: To determine the incidence of AMS symptoms and severity at 3,500 and 4,250 m above sea level. SUBJECTS AND METHODS: A population of 362 soldiers without former exposure to altitude was studied. AMS symptoms, were assessed by an extensively used standard questionnaire (Lake Louise), applied 36-72 hours after exposure to high altitude. RESULTS: A group of 200 recruits ascended to Putre (3,500 m) and a second group (162) ascended to Alto Pacollo (4,250 m). The incidence of AMS was 28% and 60% respectively (p < 0.05). Headaches and sleeping difficulties were the most frequent symptoms at both altitudes. Furthermore, severe digestive problems and dizziness were described in a high proportion of individuals at both 3,500 and 4,250 m. CONCLUSIONS: The prevalence of AMS in this study is similar to that reported elsewhere at equivalent altitudes.


Assuntos
Doença da Altitude/complicações , Doença Aguda , Adolescente , Doença da Altitude/epidemiologia , Chile/epidemiologia , Humanos , Incidência , Militares , Índice de Gravidade de Doença
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