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1.
Med Oral Patol Oral Cir Bucal ; 29(1): e128-e134, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37823297

RESUMEN

BACKGROUND: Inflammatory biomarkers, including C-reactive protein, erythrocyte sedimentation rate, neutrophil to lymphocyte ratio, platelet to lymphocyte ratio, and the systemic immune-inflammation index, have been proposed as prognostic factors diverse pathologies. However, their application for deep neck infections has yet to be clarified. MATERIAL AND METHODS: We performed a retrospective study of 163 adult patients with diagnosis of deep neck infections with the aim to evaluate the association between serological biomarkers with complications and outcomes of patients with DNI. Studied variables included demographic data, complications of DNI, outcomes, complications and death of the included subjects. The evaluated serological biomarkers were hemoglobin, leukocytes, neutrophils, lymphocytes, platelets, glucose, creatinine, albumin, CRP, and ESR. NLR, PLR, and SIII index were estimated. RESULTS: The patients' mean age was 40.6 ± 15.3 years. Complications of DNI were observed in 19.6% (n=32) patients, being the need for tracheostomy due to airway obstruction (11%, n=18) and mediastinitis (8.6%, n= 14) the most common. Evaluated subjects had an increased value of serological biomarkers (SII index 2639.9 ± 2062.9, NLR 11.3 ± 8.5, PLR 184.1 ± 108.5, CRP 12.6 ± 8.9 mg/dL, ESR 20.7 ± 9.1 mm/h). Patients with complications had a significantly higher value of all inflammatory parameters (p < 0.05). A SII index cut-off value of 2975 was selected from a ROC curve analysis. A sensitivity of 93.8%, specificity of 86.3%, a positive predictive value of 62.5%, and a negative predictive value of 98.3% are reported. The SII index was found to have an increased positive predictive value compared to NLR, PLR, and CRP for DNI complications. CONCLUSIONS: Our analysis concluded that the SII index, NLR, and PLR are valuable biomarkers to assess the risk of complications from DNI. SII index showed a high accuracy for prediction of DNI complications with a cut-off value of 2975.


Asunto(s)
Inflamación , Linfocitos , Adulto , Humanos , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Biomarcadores , Linfocitos/patología
2.
Genet Mol Res ; 14(2): 3387-99, 2015 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-25966105

RESUMEN

Although the genus Tursiops has a worldwide distribution and is globally well-studied, some dolphin populations continue to face high risks of decline. Hence, it is necessary to assess the genetic diversity and structure of this genus to properly assess its conservation status and to implement appropriate management actions. In Brazil, genetic studies on this group remain rare, particularly for populations inhabiting offshore waters. Saint Peter and Saint Paul Archipelago (SPSPA) is a small group of islands located in the Mid- Atlantic Ridge, where recent studies of the Tursiops truncatus group indicate that individuals are resident throughout the year around the archipelago, exhibiting considerable site fidelity. A previous study with this group indicated that the individuals form an isolated population. To test this hypothesis, and describe the genetic diversity of SPSPA individuals, we assessed 12 microsatellite loci and a portion of the mitochondrial control region. Bayesian analysis revealed that SPSPA bottlenose dolphins form a unique population. In a phylogeographic perspective, we found that individuals from SPSPA shared mtDNA haplotypes with inshore and offshore individuals from North Atlantic, suggesting that they are not currently isolated from their conspecifics. Mirroring mtDNA findings, microsatellite analysis revealed that most of the pairs of individuals sampled seem to be unrelated (83.8%) and no indication of inbreeding, what would be expected if a small population such as SPSPA was reproductively isolated.


Asunto(s)
Delfín Mular/genética , Animales , Océano Atlántico , Teorema de Bayes , Brasil , ADN Mitocondrial/genética , Femenino , Variación Genética , Genética de Población , Haplotipos , Islas , Región de Control de Posición , Masculino , Repeticiones de Microsatélite , Linaje , Filogenia , Filogeografía , Análisis de Secuencia de ADN , Razón de Masculinidad
3.
J Dairy Sci ; 97(10): 6400-10, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25087037

RESUMEN

Multiparous Holstein cows (n=61) were used to determine the effects of chromium propionate (Cr-Pro) supplementation during the periparturient period and early lactation on metabolism, performance, and the incidence of cytological endometritis (CE). After a 1-wk preliminary period, cows were assigned randomly to 1 of 2 treatments from 21 d before expected calving through 63 d postpartum: (1) control (n=31) and (2) Cr-Pro (n=30) administered by daily topdress at a rate of 8 mg/d of Cr. A tendency was detected for increased dry matter intake (DMI) during the prepartum period for cows fed Cr-Pro. Moreover, cows fed Cr-Pro tended to have lower plasma concentrations of nonesterified fatty acids during the prepartum period. However, effects of Cr-Pro supplementation on postpartum DMI and milk yield were not significant. Cows fed Cr-Pro tended to have higher urea N concentrations in milk. An interaction of treatment and day existed during the postpartum period, such that cows fed Cr-Pro had lower plasma glucose concentrations within the first day postpartum compared with controls. Plasma haptoglobin concentration was not affected by treatment during the postpartum period. Blood neutrophil glycogen concentrations were not affected by treatment when sampled at either 7 d postpartum or on one day between 40 and 60 d (48 d ± 0.44 standard error) postpartum. Evaluation of endometrial cytology by low volume lavage at 7 d postpartum (first lavage) and on one day between 40 and 60 d (second lavage) postpartum revealed that cows fed Cr-Pro tended to have a higher percentage of neutrophils at first lavage and decreased incidence of CE as assessed at second lavage. In conclusion, supplementation with Cr-Pro resulted in trends for increased DMI and lower plasma nonesterified fatty acids prepartum. Postpartum production and energy metabolism were not affected by treatment; however, Cr-Pro supplementation tended to affect the postpartum influx of neutrophils into the uterus and decreased the incidence of CE, suggesting positive effects of Cr-Pro supplementation on uterine health.


Asunto(s)
Enfermedades de los Bovinos/prevención & control , Bovinos/fisiología , Endometritis/veterinaria , Leche/metabolismo , Propionatos/administración & dosificación , Animales , Industria Lechera , Suplementos Dietéticos , Endometritis/prevención & control , Metabolismo Energético , Ácidos Grasos no Esterificados/sangre , Femenino , Lactancia , Paridad , Parto , Periodo Periparto , Periodo Posparto , Embarazo
4.
Water Air Soil Pollut ; 232(10): 435, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34658457

RESUMEN

Currently, hundreds of different nanomaterials with a broad application in products that make daily lives a little bit easier, in every aspect, are being produced on an industrial scale at thousands of tons per year. However, several scientists, researchers, politics, and ordinary citizens have stated their concern regarding the life cycle, collateral effects, and final disposal of these cutting-edge materials. This review summarizes, describes, and discusses all manuscripts published in the Journal Citation Reports during the last 10 years, which studied the toxicity or the effects of nanomaterials on human and environmental health. It was observed that 23.62% of the manuscripts analyzed found no ecological or human risks; 54.39% showed that several nanomaterials have toxicological effects on the ecosystems, human, or environmental health. In comparison, only 21.97% stated the nanomaterials had a beneficial impact on those. Although only 54.39% of the manuscripts reported unfavorable effects of nanomaterials on ecosystems, human, or environmental health, it is relevant because the potential damage is invaluable. Therefore, it is imperative to make toxicological studies of nanomaterials with holistic focus under strictly controlled real conditions before their commercialization, to deliver to the market only innocuous and environmentally friendly products.

5.
J Mol Graph Model ; 101: 107732, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32920240

RESUMEN

n-Aliphatic alcohols act as anesthetics only up to a certain chain length, beyond which its biological activity disappears. This is known as the 'cut-off' phenomenon. Although the most accepted explanation is based on action sites in membrane proteins, it is not well understood why alcohols alter their functions. The structural dependence of these protein receptors to lipid domains known as 'lipid rafts', suggests a new approach to tackle the puzzling phenomenon. In this work, by performing molecular dynamic simulations (MDS) to explore the lipid role, we provide relevant molecular details about the membrane-alcohol interaction at the cut-off point regime. Since the high variability of the cut-off points found on protein receptors in neurons may be a consequence of differences in the lipid composition surrounding such proteins, our results could have a clear-cut importance.


Asunto(s)
Alcoholes , Anestésicos , Lípidos , Microdominios de Membrana , Simulación de Dinámica Molecular
6.
J Dairy Sci ; 90(7): 3467-74, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17582130

RESUMEN

To test the effect of chromium propionate on glucose utilization in growing dairy heifers, 0, 5, 10, or 15 mg of chromium/d were fed to 20 Holstein heifers of 11 to 14 mo of age, in a replicated Latin square. A 2-wk adaptation period was followed by 4 periods of 2 wk each with a 2-wk flush out period between treatments. Treatments were allotted to periods in a design balanced for potential carryover effects. Chromium propionate was fed in 0.25 kg/d of ground corn individually. After 14 d on each treatment, animals were fitted with an indwelling jugular catheter, and an intravenous glucose tolerance test was conducted the following morning. Body weights increased throughout the experiment, but weights and condition scores were unaffected by treatment. Chromium supplementation increased basal glucose and decreased basal insulin and nonesterified fatty acids (NEFA) in serum in a dose-dependent, quadratic manner. Chromium increased glucose clearance rate as measured by half-life, time to nadir, and area under the curve. Over all periods, insulin concentrations tended to be lower in treated animals whereas clearance rates were unchanged. Serum NEFA levels were negatively correlated with glucose, such that treated animals with increased glucose had lower NEFA overall. There was an apparent long-term effect of chromium, because heifers in period 4 on the control diet had reduced insulin concentrations than those in the other control periods. Chromium propionate may increase glucose utilization in growing dairy heifers.


Asunto(s)
Glucemia/metabolismo , Bovinos/metabolismo , Prueba de Tolerancia a la Glucosa/veterinaria , Propionatos/farmacología , Animales , Glucemia/análisis , Glucemia/efectos de los fármacos , Constitución Corporal/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ácidos Grasos no Esterificados/sangre , Ácidos Grasos no Esterificados/metabolismo , Femenino , Inyecciones Intravenosas/veterinaria , Insulina/sangre , Insulina/metabolismo , Análisis de los Mínimos Cuadrados , Embarazo , Propionatos/administración & dosificación , Distribución Aleatoria
7.
Genome Announc ; 4(1)2016 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-26823583

RESUMEN

A complete genomic sequence of porcine parvovirus 2 (PPV-2) was detected by viral metagenome analysis on swine sera. A phylogenetic analysis of this genome reveals that it is highly similar to previously reported North American PPV-2 genomes. The complete PPV-2 sequence is 5,426 nucleotides long.

8.
J Dairy Sci ; 88(7): 2498-507, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15956312

RESUMEN

The objective was to determine action of calcium propionate and chromium propionate on lipogenesis and lipolysis in adipose tissue, dry matter (DM) intake, milk production and composition, and serum glucose and free fatty acids in Holstein dairy cattle treated from 21 d prepartum to 35 d postpartum. Twelve multiparous animals were assigned to each treatment: control (C), calcium propionate (CaP, 0.125 kg/d), chromium propionate (CrP, 10 mg of trivalent Cr/d), and both. All animals were switched to control at 36 days in milk (DIM) and the trial continued to 90 DIM. Biopsies of adipose tissue were taken at -7, 14, 28, and 56 d from calving. Control intake prepartum was 10.6 +/- 2 kg/d. Calcium propionate increased DM intake 11% prepartum and 13% postpartum; CrP increased DM intake 7 and 16%; and the combination treatment had no effect. Milk yield was 44.2 kg/d for controls and 46.8 kg/d for d 1 to 90 for CrP-treated cows. Adipose tissue lipogenesis in cows treated with either CaP or CrP was 1.25 to 78 times as fast as controls from 14 to 56 d and had returned to prepartum rates by 56 d. From 14 to 28 d, basal lipolysis in CaP- or CrP-treated cows ranged from 27 to 102% of control, whereas stimulated lipolysis was 61 to 113% of control. Milk fat yield was 92 to 95% of control on calcium and chromium propionate; the difference was similar to the net reduction in adipose lipolysis. Milk lactose, protein, and solids-not-fat did not differ among treatments. Providing a small amount of gluconeogenic precursors may reduce net lipolysis, allowing increased feed intake and milk production. The effect is thought to be through chromium acting to increase glucose flux into adipocytes.


Asunto(s)
Tejido Adiposo/metabolismo , Bovinos/metabolismo , Lactancia/efectos de los fármacos , Propionatos/administración & dosificación , Tejido Adiposo/efectos de los fármacos , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Biopsia , Glucemia/análisis , Composición Corporal , Peso Corporal , Suplementos Dietéticos , Ingestión de Alimentos/efectos de los fármacos , Ácidos Grasos no Esterificados/sangre , Femenino , Lípidos/biosíntesis , Lipólisis/efectos de los fármacos , Leche/química , Parto/fisiología , Embarazo
9.
Bioresour Technol ; 180: 112-8, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25594506

RESUMEN

The effect of pH, C/N ratio, addition of a microbial consortium (MC) and temperature upon mineralisation of Organic Fraction of Municipal Solid Waste (OFMSW) was studied; mineralisation was measured through the CO2 production rate and total CO2 formation. Through this process up to 432.9mg of CO2g(-1) initial dry matter (IDM) after 2days of treatment was obtained. It was found that under a slightly acidic pH (5-6) and C/N of 30, the mineralisation process was accelerated. Moreover, temperature (27-50°C) had no effect on the total CO2 produced. The highest CO2 production rate (5.28d(-1)) was observed at 27°C, C/N ratio of 30 and 8% of microbial consortium; it is at least 3.52 times higher than that reported (1.5d(-1)). The highest release of reducing sugars was determined at 50°C, possibly due to an increase in hydrolytic enzymes. Results suggest the potential use of rapid mineralisation of OFMSW for further friendly environmental processes.


Asunto(s)
Consorcios Microbianos , Eliminación de Residuos/métodos , Aerobiosis , Carbono/metabolismo , Dióxido de Carbono/análisis , Concentración de Iones de Hidrógeno , Minerales/química , Nitrógeno/metabolismo , Residuos Sólidos , Temperatura
10.
J Parasitol ; 80(6): 931-6, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7799166

RESUMEN

Cross immunity between Taenia solium and Taenia crassiceps parasites points to T. crassiceps cysticercosis as a convenient model to test promising antigens aimed at the development of a vaccine against T. solium cysticercosis. Since total antigens from T. crassiceps metacestodes induce significant levels of protection in pigs against T. solium cysticercosis, we initiated this work to identify the most interesting antigens involved in protection. Twelve different antigen fractions isolated from T. crassiceps cysticerci were evaluated with respect to their capacity to induce resistance against a challenge with 10 T. crassiceps cysticerci in male BALB/cAnN mice. Mice were intraperitoneally immunized with 2 doses of each antigen, 5 or 15 micrograms per mouse. The 12 antigen fractions were classified as protecting (200, 123, 74, 66, 56, 40-50, 27 and 8-14 kDa), facilitating (220-205 kDa), or irrelevant (150-160, 93, 108 kDa), according to their effect on the parasite load. The 3 most promising antigen fractions were reevaluated via subcutaneous immunization with Freund's complete adjuvant. A high level of protection was obtained when antigen fractions of 56, 66, and 74 kDa were used together. Interestingly, antigens with similar molecular weights were also detected in early steps of differentiation in T. solium cysticercosis. These observations may be helpful in the development of a synthetic or a recombinant vaccine against cysticercosis.


Asunto(s)
Antígenos Helmínticos/inmunología , Cisticercosis/prevención & control , Inmunización , Taenia/inmunología , Animales , Antígenos Helmínticos/administración & dosificación , Western Blotting , Reacciones Cruzadas , Densitometría , Modelos Animales de Enfermedad , Electroforesis en Gel de Poliacrilamida , Femenino , Adyuvante de Freund , Humanos , Inyecciones Intraperitoneales , Inyecciones Subcutáneas , Masculino , Ratones , Ratones Endogámicos BALB C
11.
J Anim Sci ; 70(6): 1928-35, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1321801

RESUMEN

Five white rot basidiomycetes were evaluated for their potential to improve ruminal degradation of oat straw and alfalfa stems. Phanerochaete chrysosporium (PC), Scytinostroma galactinum (SG), Phlebia tremellosa (PT), Phellinus pini (PP), and Pholiota mutabilis (PM) were incubated on oat straw and alfalfa stems for 30 d at 28 degrees C and 90% relative humidity. Detergent fiber and total fiber components (neutral sugars, uronic acids, Klason lignin [KL], and ester- and ether-linked non-core lignin phenolics), core lignin nitrobenzene oxidation products, and IVDMD were determined. Electron microscopy of KMnO4-stained and cellulase/colloidal gold-labeled sections was used to monitor fungal activity. Large losses of DM were noted for all fungal species on both substrates. Lignin (KL and ADL) was removed (P less than .05) from oat straw by PC and PT treatment, but no net loss of lignin was observed for fungal treatment of alfalfa stems. Cell-wall polysaccharides were removed from both substrates by fungal activity. Only PC increased (P less than .05) IVDMD of oat straw, and SG, PT, PP, and PC treatment decreased (P less than .05) IVDMD of alfalfa stems, presumably because the fungi removed the most readily fermentable polysaccharides. Transmission electron microscopy using KMnO4 staining showed a nonselective white rot attack. Cytochemical studies using colloidal gold-labeled exo- and endocellulases were used to map the location of cellulose in the cell wall before and after decay by the white rot fungi. All the white rot fungi tested had eroded and thinned cell walls. Residual cell walls were well-labeled; both endo- and exocellulose-colloidal gold identified the cellulosic wall material that remained.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Alimentación Animal , Basidiomycota/metabolismo , Grano Comestible/microbiología , Microbiología de Alimentos , Medicago sativa/microbiología , Animales , Basidiomycota/crecimiento & desarrollo , Basidiomycota/ultraestructura , Fibras de la Dieta/análisis , Digestión , Grano Comestible/química , Grano Comestible/ultraestructura , Lignina/metabolismo , Medicago sativa/química , Medicago sativa/ultraestructura , Microscopía Electrónica
12.
Rev Gastroenterol Peru ; 20(4): 434-439, 2000.
Artículo en Español | MEDLINE | ID: mdl-12140579

RESUMEN

This is the report of a patient with a 4-day history of a non-specific febrile syndrome, characterized by abdominal pain in the abscense of previous trauma. The abdominal ultrasound and Computerized Tomography showed marked hepatosplenomegaly and blood in the peritoneal cavity. An emergency splenectomy was performed, and the hospital course was complicated by and acute pancreatitis with a low-output fistula. The pathology specimen revealed the presence of a histologic picture compatible with Infectious Mononucleosis (IM), previously confirmed with serologic tests. The patient received antibiotics and had a favorable clinical course.

13.
Sci Rep ; 4: 7534, 2014 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-25520016

RESUMEN

Hundreds of substances possess anesthetic action. However, despite decades of research and tests, a golden rule is required to reconcile the diverse hypothesis behind anesthesia. What makes an anesthetic to be local or general in the first place? The specific targets on proteins, the solubility in lipids, the diffusivity, potency, action time? Here we show that there could be a new player equally or even more important to disentangle the riddle: the protonation rate. Indeed, such rate modulates the diffusion speed of anesthetics into lipid membranes; low protonation rates enhance the diffusion for local anesthetics while high ones reduce it. We show also that there is a pH and membrane phase dependence on the local anesthetic diffusion across multiple lipid bilayers. Based on our findings we incorporate a new clue that may advance our understanding of the anesthetic phenomenon.


Asunto(s)
Anestésicos/metabolismo , Lípidos de la Membrana/metabolismo , Membranas/metabolismo , Anestesia/métodos , Difusión , Concentración de Iones de Hidrógeno , Solubilidad
14.
J Mol Graph Model ; 53: 200-205, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25181454

RESUMEN

Molecular Dynamic Simulations are performed to evaluate the interaction of lidocaine, procaine and tetracaine with a lipid membrane. The main interest is to evaluate the structural changes produced by these local anesthetics in the bilayers. Penetration trajectories, interaction energies, entropy changes and an order parameter are calculated to quantify the destabilization of the lipid configurations. We show that such structural parameters give important information to understand how anesthetic agents influence the structure of plasma membranes. Graphic processing units (GPUs) are used in our simulations.


Asunto(s)
1,2-Dipalmitoilfosfatidilcolina/análogos & derivados , Anestésicos Locales/química , Lidocaína/química , Procaína/química , Tetracaína/química , 1,2-Dipalmitoilfosfatidilcolina/química , Entropía , Membrana Dobles de Lípidos/química , Conformación Molecular , Simulación de Dinámica Molecular
15.
J Phys Chem B ; 117(11): 3167-72, 2013 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-23438308

RESUMEN

The mechanism of how a noble gas modifies the excitability of nerve cells and how such excitability can be recovered under hyperbaric pressure remains unclear. Here we present a calorimetric study where the melting point depression of pure lipid membranes induced by noble gases and its recovery with a hydrostatic pressure is addressed. A correlation is found between the electric polarizability (α) of these gases and their effect on the melting transition of the membranes. These results concur with other findings to support the idea that general anesthesia only depends on the ability of a certain atom or molecule to increase the general disorder of the membrane.


Asunto(s)
Lípidos de la Membrana/química , Gases Nobles/química , Calorimetría , Presión Hidrostática , Liposomas/química , Transición de Fase
16.
Rev Sci Instrum ; 83(4): 044302, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22559553

RESUMEN

The study of motor properties of cells under appropriate physical-chemical conditions is a significant problem nowadays. The standard techniques presently used do not allow to evaluate neither large samples nor to control their thermodynamic conditions. In this work, we report a cell motility sensor based on an optical technique with a time-resolved correlation, adapted in a system able to study several samples simultaneously. Image correlation analysis is used to follow their temporal behavior. A wide variety of motile cells, such as archaea, bacteria, spermatozoa, and even contractile cells, can be studied using this technique. Here, we tested our technique with the study of sperm motility. In particular, both the sperm motility and its prevalence are studied under a temperature range from 0 to 37 °C. We found that incubation at 10 °C presents the lengthiest prevalence in motility and observed, for the first time, an interesting thermal reversibility behavior.


Asunto(s)
Dispositivos Ópticos , Motilidad Espermática , Temperatura , Animales , Masculino , Ratones , Factores de Tiempo
17.
Sci Total Environ ; 412-413: 257-64, 2011 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-22033361

RESUMEN

Agricultural application of wastewater sludge has become the most widespread method of disposal, but the environmental effects on soil, air, and crops must be considered. The effect of wastewater sludge or urea on sunflower's (Helianthus annuus L.) growth and yield, the soil properties, and the resulting CO(2) and N(2)O emissions are still unknown. The objectives of this study were to investigate: i) the effect on soil properties of organic or inorganic fertilizer added to agricultural soil cultivated with sunflower, ii) how urea or wastewater sludge increases CO(2) and N(2)O emissions from agricultural soil over short time periods, and iii) the effect on plant characteristics and yield of urea or wastewater sludge added to agricultural soil cultivated with sunflower. The sunflower was fertilized with wastewater sludge or urea or grown in unamended soil under greenhouse conditions while plant and soil characteristics, yield, and greenhouse gas emissions were monitored. Sludge and urea modified some soil characteristics at the onset of the experiment and during the first two months but not thereafter. Some plant characteristics were improved by sludge. Urea and sludge treatments increased the yield at similar rates, while sludge-amended soil significantly increased N(2)O emissions but not CO(2) emissions compared to the other amended or unamended soils. This implies that wastewater sludge increased the biomass and/or the yield; however, from a holistic point of view, using wastewater sludge as fertilizer should be viewed with concern.


Asunto(s)
Dióxido de Carbono/análisis , Fertilizantes/análisis , Helianthus/crecimiento & desarrollo , Óxido Nitroso/análisis , Suelo/química , Productos Agrícolas/crecimiento & desarrollo , Conductividad Eléctrica , Concentración de Iones de Hidrógeno , Análisis de Componente Principal , Aguas del Alcantarillado/análisis , Suelo/análisis , Urea/análisis
18.
Phys Rev E Stat Nonlin Soft Matter Phys ; 81(1 Pt 1): 011301, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20365362

RESUMEN

Acoustic gaps are normally observed in granular inhomogeneous structures made of composite materials. The modulation of the elastic properties in such media creates the coherent effects of scattering and interference that ultimately lead to frequency intervals where sound propagation is forbidden. Contrastingly, we report here an experimental observation of acoustic gaps in homogeneous media; specifically, in granular chains. The beads used in our study are magnetic. Therefore, instead of modulating the elastic properties of the chain, we modulate the magnetization (i.e., the contact forces). We also observe that the propagation speed of acoustic signals through the magnetic chains used in this study is at odds with the speed predicted by Hertz's law.

20.
J Anim Sci ; 87(12): 4032-41, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19717765

RESUMEN

The purpose of this research was to investigate the effect of Cr as chromium propionate (CrProp) on growth performance, carcass traits, meat quality, and the fatty acid profile of fat from pigs fed no supplemented dietary fat, choice white grease (CWG), or tallow. An experiment was conducted with 108 crossbred Yorkshire gilts assigned in a randomized complete block design based on BW (average initial and final BW were 29 +/- 3 and 109 +/- 7 kg, respectively) and allotted within block to a 2 x 3 factorial arrangement of treatments. The treatment arrangement consisted of 2 levels of Cr supplementation (0 and 200 microg/kg in the form of CrProp) and 3 dietary fat sources (no added fat, CWG, or tallow). Each treatment was replicated 6 times with 3 pigs per replicate pen. The experiment was conducted over time with 3 replicates in each of 2 trials. A 4-phase grower-finisher feeding program was used. Dietary treatments were 1) a corn-soybean meal (C-SBM) diet with no added fat; 2) a C-SBM diet with 4% added tallow; 3) a C-SBM diet with 4% added CWG; 4) diet 1 + 200 microg/kg of Cr as CrProp; and 5) diet 2 + 200 microg/kg of Cr; 6) diet 3 + 200 microg/kg of Cr. Addition of Cr did not affect (P > 0.10) growth performance, but did decrease (P = 0.05) 10th-rib backfat and increase (P = 0.03) percentage of muscle. Gain:feed was increased (P = 0.003) and ADFI was decreased (P = 0.03) by fat addition. Fat addition increased HCW (P = 0.05) and dressing percent (P = 0.03). Average backfat, 9th-rib LM cook loss, and 10th-rib LM drip loss and total loss were decreased (P = 0.02 to 0.04) by tallow. Belly bending on both the teatline and scribe side were increased (P = 0.01 to 0.03) by CWG. Iodine values on belly fat samples were decreased (P = 0.02) by Cr supplementation. In addition, iodine values on belly and loin fat samples were increased (P = 0.001) by CWG. Overall, Cr supplementation decreased backfat and the iodine value of belly fat and increased the percentage of muscle.


Asunto(s)
Suplementos Dietéticos , Ácidos Grasos/análisis , Carne/normas , Propionatos/farmacología , Porcinos/crecimiento & desarrollo , Alimentación Animal/análisis , Animales , Grasas de la Dieta/farmacología , Grasas/análisis , Grasas/farmacología , Femenino , Carne/análisis
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