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1.
Waste Manag ; 119: 202-214, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33070090

RESUMEN

Short-term on-site composting of poultry carcasses and broiler litter (BL) is considered as a feasible technology for pathogen elimination during events of mass mortality in poultry houses. However, factors related to mass losses and physical transformation of the poultry carcass, and associated emissions of volatile organic compounds (VOCs) and odors, have not been thoroughly evaluated. This study aims to characterize the degradation of separated carcass parts co-composted with BL and the associated air emissions during 30 days of enclosed composting at 50 °C with constant aeration. The study was carried out in lab-scale simulators using five mixtures containing feathers, rib bones, skins, breast muscles, and hearts and livers, prepared at a 1:2 volumetric ratio (carcass:BL). Dry mass losses reached 59.5, 41.1, 60.8 and 103.5% (based on weight) or 48.4, 29.6, 49.7, and 94.8% (based on CO2-C and NH3-N emissions), for rib bones, skins, breast muscles, and hearts and livers, respectively. Visually, most of the carcass parts were degraded, and the typical carcass odor had disappeared by the end of the 30 days. Out of 24 VOCs, dimethyl disulfide (DMDS) and dimethyl trisulfide (DMTS) contributed 80.7-88.3% of the total VOC flux, considering the partial contribution of each part to the emissions involved with the whole carcass. DMDS, DMTS, benzaldehyde, methanethiol, pentanoic acid, and NH3, contributed 90.5-97.9% of the odor activity values during composting. DMDS/DMTS ratio is suggested as a potential biomarker of stabilization and readiness of the compost for transportation toward further treatment or safe burial.


Asunto(s)
Compostaje , Animales , Pollos , Estiércol , Odorantes , Aves de Corral , Suelo
2.
Waste Manag ; 78: 969-979, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32559993

RESUMEN

Composting in closed polyethylene sleeves with forced aeration may minimize odor emissions, vectors attraction and leachates associated with open windrows. The present study demonstrates the use of this system for composting olive mill wastewater (OMW), the undesired stream associated with the olive milling industry. A polyethylene sleeve of 1.5-m diameter and ca. 20-m long was packed with shredded municipal green waste which was pre-soaked in OMW for 72 h. Process conditions were controlled by means of a programmable logic controller (PLC) equipped with temperature and oxygen sensors. Thermophilic temperatures (>45 °C) were maintained for one month followed by temperatures in the range of 30-40 °C, ca. 20 °C above ambient temperature, for a period of 3.5 months. Oxygen levels were controlled and the system was kept aerobic. Water content gradually decreased with sufficient levels for efficient composting. The finished compost was non-phytotoxic to Cress (Lepidium sativum L.) in a lab bioassay. It was also found suitable as an ingredient in peat, tuff, and coir based growing media, evaluated by plant growth tests with basil and ornamental plants. The viability of this approach for disposing off OMW is much dependent on the liquid absorption capacity of the vegetative waste.

3.
Waste Manag ; 72: 150-160, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29174066

RESUMEN

Understanding and optimization of composting processes can benefit from the use of controlled simulators of various scales. The Agricultural Research Organization Composting Simulator (ARO-CS) was recently built and it is flexibly automated by means of a programmable logic controller (PLC). Temperature, carbon dioxide, oxygen and airflow are monitored and controlled in seven 9-l reactors that are mounted into separate 80-l water baths. The PLC program includes three basic heating modes (pre-determined temperature profile, temperature-feedback ("self-heating"), and carbon dioxide-dependent temperature), three basic aeration modes (airflow dependence on temperature, carbon dioxide, or oxygen) and enables all possible combinations among them. This unique high flexibility provides a robust and valuable research tool to explore a wide range of research questions related to the science and engineering of composting. In this article the logic and flexibility of the control system is presented and demonstrated and its potential applications are discussed.


Asunto(s)
Dióxido de Carbono , Compostaje , Oxígeno , Suelo , Temperatura
4.
Waste Manag ; 67: 32-42, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28595805

RESUMEN

Composting in polyethylene sleeves with forced aeration may minimize odor emissions, vectors attraction and leachates associated with open windrows. A disadvantage of this technology is the lack of mixing during composting, potentially leading to non-uniform products. In two pilot experiments using biosolids and green waste (1:1; v:v), thermophilic conditions (>45°C) were maintained for two months, with successful control of oxygen levels and sufficient moisture. Emitted odors declined from 1.5-3.8×105 to 5.9×103-2.3×104 odor units m-3-air in the first 3weeks of the process, emphasizing the need of odor control primarily during this period. Therefore, composting might be managed in two phases: (i) a closed sleeve for 6-8weeks during which the odor is treated; (ii) an open pile (odor control is not necessary). Reduction of salmonella, E. coli and coliforms was effective initially, meeting the standards of "Class A" biosolids; however, total and fecal coliforms density increased after opening the second sleeve and exceeded the standard of 1000 most probable number (MPN) per g dry matter. Compost maturity was achieved in the open piles following the two sleeves and the final compost was non-phytotoxic and beneficial as a soil additive.


Asunto(s)
Compostaje , Escherichia coli , Polietileno , Odorantes , Oxígeno , Suelo
5.
J Nucl Med ; 16(4): 324-5, 1975 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1113190

RESUMEN

A patient with dissecting aneurysm of the ascending aorta and hemopericardium showed a widened mediastinum on posterior lung scan.


Asunto(s)
Enfermedades Pulmonares/diagnóstico , Enfermedades del Mediastino/etiología , Cintigrafía , Anciano , Aneurisma de la Aorta/complicaciones , Femenino , Humanos , Microesferas , Derrame Pericárdico/complicaciones , Albúmina Sérica , Tecnecio
6.
Bioresour Technol ; 107: 87-96, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22226593

RESUMEN

Olive mill wastewaters (OMW) were obtained at laboratory scale by milling olives from four cultivars grown at different irrigation levels and harvested at different times. Samples were compared based on wastewater quantity, pH, suspended matter, salinity, organic load, total phenols, NPK, and phytotoxicity. Principal component analysis discriminated between harvest times, regardless of olive cultivar, indicating substantial influence of fruit ripeness on OMW characteristics. OMW properties were affected both by the composition and the extraction efficiency of fruit water. As the fruit water content increased, the concentrations of solutes in the fruit water decreased, but the original fruit water composed a larger portion of the total wastewater volume. These contradicting effects resulted in lack of correlation between fruit water content and OMW properties. The significant effects shown for fruit ripeness, irrigation and cultivar on OMW characteristics indicate that olive horticultural conditions should be considered in future OMW management.


Asunto(s)
Riego Agrícola , Industria de Alimentos , Residuos Industriales , Olea , Contaminantes del Agua , Concentración de Iones de Hidrógeno
7.
Bioresour Technol ; 101(17): 6699-706, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20399644

RESUMEN

Successful co-composting of solid and liquid olive mill wastes (OMW) and obtaining a product of horticultural value may increase the viability of this recycling approach. Two composting cycles were performed, in which olive mill solid wastes (OMSW) were used to form five mixtures, wetted either with fresh water or with olive mill wastewater (OMWW). Up to approximately 0.3m(3) of OMWW could be applied to each m(3) of the raw materials without negatively affecting the chemical, physical and horticultural properties of the resulted composts. A growing media composed of perlite amended with 25-33% OMW-composts showed higher suppressiveness against Fusarium oxysporum f. sp. melonis as compared to equivalent perlite:peat moss mixtures. The yields of tomato plants grown in peat moss amended with 20% (v:v) of OMW-composts were not significantly different than plants grown in unamended peat. The viability of co-composting as a treatment approach for OMWW is discussed in the context of management aspects and the horticultural value of the final product.


Asunto(s)
Industria de Alimentos , Residuos Industriales , Olea , Suelo , Bioensayo
11.
J Anim Sci ; 87(5): 1835-48, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19122047

RESUMEN

Livestock odors are largely caused by several groups of volatile organic compounds (VOC), including sulfur-containing compounds, VFA, and phenols and indoles. Throughout the growth stages of cattle in the nursery and feedlot, distinctly different diets are formulated to meet the changing requirements of the animal. Because diet composition and manure management are 2 major factors affecting odor emissions, it was assumed that changes in diet composition along the development of calves would affect VOC emissions from fresh and stored manure. In this study, the dynamics of gas-phase VOC in feces from 6 Holstein-Friesian bull calves were followed at 5 ages: 1 to 5 wk (stage I), 6 to 8 wk (stage II, before weaning), 9 to 14 wk (stage III, after weaning), and 15 to 36 wk (stages IV and V). The CP content of the formulated diet decreased from 23.0 to 13.9%. Samples of fresh feces were incubated under either aerobic or anaerobic conditions for 21 d. The VOC were analyzed from the feces headspace by solid-phase microextraction, followed by gas chromatography-mass spectrometry. Distinct changes in gas-phase VOC were observed in fresh and aged feces from calves at different ages. Semiquantitatively (based on comparative peak area counts), the following trends were observed: 1) S-containing compounds were the least dominant in fresh feces at the age of 2 wk (stage I), whereas VFA esters were the most dominant. 2) At the age of 7 wk (stage II), 1 wk before calves were weaned, feces seemed to be the most offensive, presumably because of the difficulty of synchronizing the requirements of the animal and the diet formulation during this stage of rapid development. 3) The VOC decreased during storage of feces under aerobic conditions but significantly increased at all 5 life stages during storage under anaerobic conditions. This study demonstrates that life stage and manure management affect odor emissions from beef fattening operations. Incorporation of the age and diet of calves in odor modeling could improve annoyance predictions.


Asunto(s)
Bovinos/crecimiento & desarrollo , Dieta/veterinaria , Gases/análisis , Estiércol/análisis , Aerobiosis , Anaerobiosis , Animales , Peso Corporal , Cromatografía de Gases y Espectrometría de Masas , Concentración de Iones de Hidrógeno , Masculino , Factores de Tiempo , Orina/química
12.
Environ Sci Technol ; 42(2): 536-42, 2008 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-18284159

RESUMEN

We tested the possibility of using tree cores to detect unknown subsurface contamination by chlorinated volatile organic compounds (Cl-VOCs) and petroleum hydrocarbons, a method we term "phytoscreening". The scope and limitations of the method include the following: (i) a number of widespread Cl-VOC contaminants are readily found in tree cores, although those with very high vapor pressures or low boiling points may be absent; (ii) volatile petroleum hydrocarbons were notwell-expressed in tree cores; (iii) trees should be sampled during active evapotranspiration and from directions that are well exposed to sunlight; (iv) there is not necessarily a direct correlation between concentrations measured in tree cores and those in the subsurface; (v) detection of a contaminant in a tree core indicates that the subsurface is contaminated with the pollutant; (vi) many possible causes of false negatives may be predicted and avoided. We sampled trees at 13 random locations in the Tel Aviv metropolitan area and identified Cl-VOCs in tree coresfromthree locations. Subsequently, subsurface contamination at all three sites was confirmed. Phytoscreening is a simple, fast, noninvasive, and inexpensive screening method for detecting subsurface contamination, and is particularly useful in urban settings where conventional methods are difficult and expensive to employ.


Asunto(s)
Cupressus/metabolismo , Hidrocarburos/metabolismo , Magnoliopsida/metabolismo , Árboles , Contaminantes Químicos del Agua/metabolismo , Monitoreo del Ambiente , Israel , Abastecimiento de Agua/análisis
13.
Artículo en Inglés | MEDLINE | ID: mdl-696410

RESUMEN

The tolerance level of normal tissue, which is the concept of NSD, is the limiting factor in radiation therapy. It is well known that the two parallel opposing fields should be treated at each session instead of alternating one field per session. The biologic effect ratios between the normal tissue at the depth of maximum build-up and the midline for parallel opposing fields were published by ELLIS et coll. General formulae are now presented providing biologic effect ratio at any two locations in terms of per cent depth doses in the treatment volume for parallel opposing fields. Examples at the depth of maximum build-up and certain depth of the connective tissue at the tumor site are also given.


Asunto(s)
Relación Dosis-Respuesta en la Radiación , Neoplasias/radioterapia , Dosificación Radioterapéutica , Piel/efectos de la radiación , Animales , Radioisótopos de Cobalto , Humanos , Matemática , Tolerancia a Radiación , Teleterapia por Radioisótopo
14.
Environ Sci Technol ; 36(5): 1054-60, 2002 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-11917991

RESUMEN

Humic substances originated from aquatic, soil, or sediment environments are mixtures of humic compounds with various characteristics. Sorption interactions with isolated, well defined humic fractions can be studied either in an aqueous phase ("dissolved humic substances"), or in a solid-phase, by coating mineral particles with the humic materials, or simply by working with humic acid particles (powder) at low pH to minimize dissolution. Each attitude, by definition, can be studied by different experimental techniques and has a different meaning for understanding natural environmental processes. In this study, a new tool for studying sorption interactions is presented. Sol-gel was used as an inert matrix to immobilize (entrap) various humic acids (HAs), and then used to study the interactions of several polycyclic aromatic hydrocarbons (PAHs) with the entrapped HA. Linear and nonlinear sorption coefficients were highly correlated with contaminant hydrophobicity. Sorption of pyrene to immobilized HA was in the order of soil HA > Aldrich HA approximately = peat HA. It was concluded that the entrapped HAs retained their original properties in the gel matrix and were accessible to the external contaminant through the pore network. Additionally, binding coefficients of pyreneto dissolved humic substances and to dissolved organic matter (DOM) were determined from the reduction in pyrene sorption to immobilized HA in the presence of dissolved humic material or DOM in solution. Binding coefficients of pyrene were in the order of the following: dissolved Aldrich HA > dissolved peat fulvic acid (FA) > DOM derived from mature compost > DOM derived from fresh compost.


Asunto(s)
Monitoreo del Ambiente/métodos , Sustancias Húmicas/análisis , Contaminantes del Suelo/análisis , Contaminantes del Agua/análisis , Adsorción , Técnicas de Química Analítica/métodos , Sustancias Húmicas/química , Concentración de Iones de Hidrógeno , Tamaño de la Partícula , Suelo , Solubilidad
15.
J Surg Oncol ; 12(4): 299-303, 1979 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-574912

RESUMEN

In our series of 37 patients with Kaposi's sarcoma, a larger than expected incidence of Americans of Italian and Jewish lineage was found, with 51% of Italian and 38% of Jewish background. Although a predominance of these two groups has been clearly shown previously, this may be the highest percentage of any series. In addition, 12, or 32%, of the patients were found to have concurrent diabetes mellitus. This association has been observed previously, but is not generally appreciated.


Asunto(s)
Sarcoma de Kaposi/epidemiología , Adolescente , Adulto , África/etnología , Negro o Afroamericano , Factores de Edad , Anciano , Población Negra , Niño , Complicaciones de la Diabetes , Diabetes Mellitus/epidemiología , Femenino , Hemangiosarcoma , Registros de Hospitales , Humanos , Italia/etnología , Judíos , Masculino , Persona de Mediana Edad , Sarcoma de Kaposi/complicaciones , Factores Sexuales , Estados Unidos
16.
Cancer ; 45(3): 427-31, 1980 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7353196

RESUMEN

Fourteen patients with Kaposi's sarcoma (KSY were treated systemically with vinblastine sulfate in a low-dose regimen and compared with 23 patients reported in the medical literature. The therapeutic results in our series were excellent in terms of regression of cutaneous lesions. Vinblastine appears to be a drug that is well suited for the management of KS in an outpatient setting. Intravenous therapy may be supplemented with intralesional or intraarterial vinblastine.


Asunto(s)
Sarcoma de Kaposi/tratamiento farmacológico , Neoplasias Cutáneas/tratamiento farmacológico , Vinblastina/uso terapéutico , Adulto , Anciano , Femenino , Humanos , Leucopenia/inducido químicamente , Masculino , Persona de Mediana Edad , Remisión Espontánea , Factores de Tiempo , Vinblastina/administración & dosificación , Vinblastina/efectos adversos
17.
J Med ; 11(1): 49-63, 1980.
Artículo en Inglés | MEDLINE | ID: mdl-6995548

RESUMEN

The effect of serum of patients with solid tumors on the phagocytic activity of normal neutrophilic granulocytes was investigated. The largest groups of tumors studied were carcinoma of colon/rectum, sarcomas and melanomas. Sera from all three groups of patients were found to have highly significant (p < 0.001) stimulatory effects on granulocyte phagocytic activity. These findings contrast with previously reported depression of granulocyte phagocytic activity associated with various forms of leukemia and lymphomas.


Asunto(s)
Neoplasias/sangre , Neutrófilos/fisiología , Fagocitosis , Ensayos Clínicos como Asunto , Neoplasias del Colon/sangre , Humanos , Melanoma/sangre , Neoplasias del Recto/sangre , Sarcoma/sangre
18.
J Surg Oncol ; 12(2): 131-5, 1979.
Artículo en Inglés | MEDLINE | ID: mdl-491681

RESUMEN

A 59-year-old black woman presented with an ill-defined plaque on her nose. This appeared clinically suggestive of a sclerosing type of basal cell epithelioma (BCE). Microscopic sections demonstrated this diagnosis. Multiple excisions employing the microscopically controlled technique of Mohs traced the tumor deep into the nasal cartilage before histologic sections were free of tumor cells. This type of BCE deserves well planned therapy because of its destructive potential.


Asunto(s)
Carcinoma Basocelular/diagnóstico , Neoplasias Nasales/diagnóstico , Neoplasias Cutáneas/diagnóstico , Carcinoma Basocelular/patología , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Nasales/patología , Neoplasias Cutáneas/patología
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