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1.
J Mol Model ; 23(5): 159, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28405847

RESUMEN

The nonidempotency measure of Löwdin is found to be proportional to the disequilibrium. It is shown that there exists a simple relationship between the LMC (López-Ruiz-Mancini-Calbet) and the generalized statistical complexities and the generalized nonidempotency measure of Löwdin. Results are illustrated for an exactly solvable two-electron model atom.

2.
Sci Total Environ ; 569-570: 784-797, 2016 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-27392333

RESUMEN

An understanding of the processes controlling sediment, organic matter and metal export is critical to assessing and anticipating risk situations in water systems. Concentrations of suspended particulate matter (SPM), dissolved (DOC) and particulate (POC) organic carbon and metals (Cu, Ni, Pb, Cr, Zn, Mn, Fe) in dissolved and particulate phases were monitored in a forest watershed in the Basque Country (Northern Spain) (31.5km(2)) over three hydrological years (2009-2012), to evaluate the effect of flood events on the transport of these materials. Good regression was found between SPM and particulate metal concentration, making it possible to compute the load during the twenty five flood events that occurred during the study period at an annual scale. Particulate metals were exported in the following order: Fe>Mn>Zn>Cr>Pb>Cu>Ni. Annual mean loads of SPM, DOC and POC were estimated at 2267t, 104t and 57t, respectively, and the load (kg) of particulate metals at 76 (Ni), 83 (Cu), 135 (Pb), 256 (Cr), 532 (Zn), 1783 (Mn) and 95170 (Fe). Flood events constituted 91%-SPM, 65%-DOC, 71%-POC, 80%-Cu, 85%-Ni, 72%-Pb, 84%-Cr, 74%-Zn, 87%-Mn and 88%-Fe of total load exported during the three years studied. Flood events were classified into three categories according to their capacity for transporting organic carbon and particulate metals. High intensity flood events are those with high transport capacity of SPM, organic carbon and particulate metals. Most of the SPM, DOC, POC and particulate metal load was exported by this type of flood event, which contributed 59% of SPM, 45% of organic carbon and 54% of metals.


Asunto(s)
Inundaciones , Sedimentos Geológicos/análisis , Metales/análisis , Material Particulado/análisis , Ríos/química , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , España
3.
J Phys Condens Matter ; 27(17): 175003, 2015 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-25791771

RESUMEN

Uncertainty relations are studied for a characterization of topological-band insulator transitions in 2D gapped Dirac materials isostructural with graphene. We show that the relative or Kullback-Leibler entropy in position and momentum spaces, and the standard variance-based uncertainty relation give sharp signatures of topological phase transitions in these systems.

4.
J Chem Theory Comput ; 9(2): 1068-72, 2013 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-26588749

RESUMEN

It is shown that there is a one-to-one map between the ground state wave function and the control parameter. Wu et al. [Phys. Rev. A2006, 74, 052335] introduced an analogue of the Density Functional Theory (DFT) density and showed that the "density" determines the "control parameter" (corresponding to the DFT "external potential"). We prove that any strictly monotonous function can be used to obtain a new density with a different control parameter (or DFT "external potential"), and the new density determines the new control parameter. Moreover, there is also a one-to-one map between the Rényi entropy of a given order and the control parameter. Therefore, the Rényi entropy can be used as a control parameter.

5.
Environ Pollut ; 156(3): 840-8, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18602203

RESUMEN

The aim of the study was to establish whether the repeated application of sewage sludge to an acid forest soil (Dystric Cambisol) would lead to short-term groundwater contamination. Sludge was applied at four loading rates (0, 2.4, 17 and 60 Mg ha(-1)) in two consecutive years and leachates were analysed. Heavy metal inputs to soils at the lowest dose were below EC regulations but, at higher doses, limits for Zn, Cd, Cr and Ni were exceeded. Repeated application of sludge at 60 Mg ha(-1) resulted in significantly (P<0.05) higher concentrations of Zn, Cd, Cr and Ni in the leachates than with other treatments. The drinking water standards for Cd and Ni were surpassed in all treatments. Control plots were contaminated by groundwater flow despite the existence of buffer zones between plots. This complicated interpretation of the results, highlighting the importance of careful design of this type of experiment.


Asunto(s)
Metales Pesados/análisis , Eliminación de Residuos/métodos , Aguas del Alcantarillado , Suelo/análisis , Árboles , Adsorción , Cadmio/análisis , Fraccionamiento Químico , Cromo/análisis , Ecología/métodos , Fertilizantes , Concentración de Iones de Hidrógeno , Modelos Estadísticos , Níquel/análisis , Contaminantes del Suelo/análisis , Zinc/análisis
6.
Bioresour Technol ; 99(11): 4684-93, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17986392

RESUMEN

The sorption uptake of cadmium, nickel, zinc, copper and lead by marine brown alga Fucus spiralis was investigated in bimetallic, trimetallic and multimetallic solutions. The experimental data fitted very well to Langmuir model. In bimetallic systems, the affinity of biomass for lead and copper increased and the sorption uptake of these metals was not affected by increasing concentrations of cadmium, nickel or zinc. However, in solutions with both metals there was a significant mutual decrease of their sorption levels at high concentrations of the other metal. The sorption uptake of cadmium, nickel and copper was investigated in trimetallic aqueous systems. Based on the kinetic parameter b, the affinity of F. spiralis for copper was considerably higher than for cadmium or nickel: bCd=6.39, bNi=1.82 and bCu=17.89. In all tests, the maximum sorption uptake remained practically constant around 1 mmol/g, indicating that the number of active sites on the biomass was limited. Tests with four and five metals showed that copper was preferentially adsorbed. The differences between the experimental sorption data and those given by the chemical speciation program PHREEQCI were negligible. In general, the software used provided satisfactory estimated data for each metal and hence can be a useful tool to predict or simulate the real process.


Asunto(s)
Fucus/metabolismo , Metales Pesados/aislamiento & purificación , Adsorción , Biodegradación Ambiental , Simulación por Computador , Temperatura
7.
Bioresour Technol ; 98(17): 3344-53, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17624771

RESUMEN

Sorption capacity of six different algae (green, red and brown) was evaluated in the recovery of cadmium, nickel, zinc, copper and lead from aqueous solutions. The optimum sorption conditions were studied for each monometallic system. The optimum pH was 6 for the recovery of Cd, Ni and Zn, and less than 5 for Cu and Pb. The best results were obtained with the lowest biomass concentration used (0.5 g/L). Experimental data fitted a Langmuir model very well according to the following sequence of the sorption values: Pb>Cd> or =Cu>Zn>Ni. The brown algae achieved the lowest metal concentration levels in solution; the best results were obtained with Fucus spiralis. Finally, a software computer program was used to simulate the process by comparison of theoretical with experimental results and show minimum differences between both types of data.


Asunto(s)
Eucariontes/metabolismo , Metales Pesados/metabolismo , Bacterias/metabolismo , Biodegradación Ambiental , Biomasa , Eucariontes/química , Hongos/metabolismo , Concentración de Iones de Hidrógeno , Metales Pesados/química , Contaminantes Químicos del Agua/metabolismo , Contaminación Química del Agua/prevención & control
8.
Rev. senol. patol. mamar. (Ed. impr.) ; 20(2): 80-82, 2007. ilus
Artículo en Español | IBECS | ID: ibc-74277

RESUMEN

El angiosarcoma postradioterapia es un tumor raro que surgeasociado al tratamiento conservador del cáncer de mama.Es preciso diferenciarlo de otras formas de angiosarcoma relacionadoscon la mama como son el angiosarcoma primario yel síndrome de Stewart-Treves. Suelen presentarse como sarcomasde alto grado localizado en la piel o tejido subcutáneoy con menos frecuencia en el parénquima mamario. Tienenun periodo de latencia variable aunque inferior al de otros sarcomasradioinducidos. El único tratamiento curativo es la cirugía,si bien la elevada tendencia a la recurrencia de estos tumoreshace que la cirugía radical no sea capaz de prevenir lareaparición de la enfermedad en muchos casos. Presentamosdos casos de angiosarcoma radioinducido con distinta evolucióntras su tratamiento(AU)


Postradiation angiosarcomas are infrequent tumours thatarise associated to conservative treatment of breast cancer. Itis needed to distinguish between them and other types of breastangiosarcomas like primary angiosarcoma or Stewar-Trevessyndrome. They usually present as high grade sarcomaslocated at skin or subcutaneous tissue and less frequent in breastparenchyma. They have a variable latency time that is lowerthan the other radioinduced sarcomas. Surgery is the onlycurative treatment although the high relapse rate makes thatradical surgery is not be able to prevent the recurrence in mostcases. We present two cases of radioinduced angiosarcomawith different outcome after their treatment(AU)


Asunto(s)
Humanos , Femenino , Persona de Mediana Edad , Hemangiosarcoma/complicaciones , Hemangiosarcoma/diagnóstico , Hemangiosarcoma/radioterapia , Neoplasias de la Mama/complicaciones , Neoplasias de la Mama/radioterapia , Neoplasias de la Mama/cirugía , Recurrencia Local de Neoplasia/complicaciones , Hemangiosarcoma/fisiopatología , Hemangiosarcoma/cirugía , Carcinoma Intraductal no Infiltrante/complicaciones , Carcinoma Intraductal no Infiltrante/radioterapia , Hemangiosarcoma/epidemiología , Pronóstico
9.
Crit Rev Biotechnol ; 26(4): 223-35, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17095433

RESUMEN

The state of the art in the field of biosorption using algae as biomass is reviewed. The available data of maximum sorption uptake (qmax) and biomass-metal affinity (b) for Cd2 +, Cu2 +, Ni2 +, Pb2 + and Zn2 + were statistically analyzed using 37 different algae (20 brown algae, 9 red algae and 8 green algae). Metal biosorption research with algae has used mainly brown algae in pursuit of treatments, which improve its sorption uptake. The information available in connection with multimetallic systems is very poor. Values of qmax were close to 1 mmol/g for copper and lead and smaller for the other metals. Metal recovery performance was worse for nickel and zinc, but the number of samples for zinc was very small. All the metals except lead present a similar affinity for brown algae. The difference in the behavior of lead may be due to a different uptake mechanism. Brown algae stand out as very good biosorbents of heavy metals. The best performer for metal biosorption is lead.


Asunto(s)
Eucariontes/metabolismo , Metales Pesados/aislamiento & purificación , Adsorción , Biodegradación Ambiental , Metales Pesados/química , Purificación del Agua/métodos
10.
Chemosphere ; 65(11): 2456-67, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16765420

RESUMEN

A column leaching study was carried out over a period of 77 days to determine the changes in the chemistry of an acid soil and of the corresponding leachates after the addition of an anaerobic sludge (equivalent to 69 Mg DW ha(-1)). By the end of the experiment, the addition of the sludge to the soil had induced an increase in soil pH (from pH 3.6-4.0 to pH 4.1-4.8), in spite of the pronounced decrease in pH detected in the leachates by day 18 of the experiment. The decrease in pH (down to pH 3.3) occurred at the same time as leachate SO(4) and Fe peaked. Once the acidification attributed to sulphide oxidation ceased, the "liming effect" of the sludge became evident and counteracted further proton production - such as that associated with oxidation of NH(4) - at least for the duration of the study. Concentrations of Zn, Cd, Ni, and to a lesser extent, Pb in leachates displayed pulses at the beginning of the experiment (first 12 days), whereas the concentration of Cu followed a more irregular pattern; the concentrations of these metals never surpassed the European threshold values for drinking water. In contrast, concentrations of NO(3), Mn, and Cr in leachates had increased by the end of the experiment - in parallel with an increase in dissolved organic C (DOC) - and surpassed the European threshold for drinking water. Mineralisation of native soil organic C (SOC) was enhanced by the addition of this N-rich residue, and the organic C mass balance at the end of the experiment was negative. Nitrogen mass balance, although positive, exhibited a loss of 77% of the N added to the system. The results obtained indicate that application of this sewage sludge to a soil with a pH<5, at the loading rate used here, and without liming (i.e., non fulfilment of the requirements of the present European Directive) may pose a risk in terms of groundwater contamination.


Asunto(s)
Anaerobiosis , Aguas del Alcantarillado , Suelo , Ácidos
11.
Forensic Sci Int ; 149(1): 57-65, 2005 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-15734111

RESUMEN

Using the entomological evidence obtained in several forensic cases analyzed in our laboratory for comparison, we evaluated the results of an experimental study carried out in a semiurban setting to determine the structure of the sarcosaprophagous fauna from a Mediterranean region of SE Spain. In all, 18 orders of arthropods were collected. The summarized experimental results refer to the most important taxa for estimating the postmortem interval. Thus, the seasonal character of certain Diptera species, such as Phaenicia sericata, Calliphora vicina, Chrysomya albiceps and Musca domestica, is cited. Among the Coleoptera, the role of Dermestidae as a necrophagous species, and of Staphylinidae and Histeridae as necrophilous, or Cleridae, Tenebrionidae and Nitidulidae as omnivorous, as well as their appearance on the corpse, is described. Among the Hymenoptera, Formicidae were as the most abundant group, acting as omnivores and not apparently related to any particular decomposition stage. The real cases are discussed using data from the literature and the experimentally obtained results. In every case, the most relevant factors for estimating PMI are briefly discussed, mentioning, when possible, the relation with the experimental results. We confirm the significance of the experimental results because they seem to be applicable to actual forensic cases, the details of which enlarge our very little knowledge on the subject in the Iberian Peninsula. The importance of regional faunistic studies of the sarcosaprophagous arthropod community, the results of which may be applied to forensic practice, is mentioned.


Asunto(s)
Artrópodos , Entomología , Conducta Alimentaria , Medicina Legal/métodos , Cambios Post Mortem , Adulto , Animales , Femenino , Humanos , Larva , Masculino , Estaciones del Año , España
12.
J Chem Phys ; 120(16): 7369-73, 2004 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-15267646

RESUMEN

Structural characteristics of the spherically averaged internally folded density or reciprocal form factor Br are studied within the Hartree-Fock framework for 103 neutral atoms, 54 singly charged cations, and 43 anions in their ground state. The function Br is classified throughout the Periodic Table into three types: (i) monotonic decrease from the origin, (ii) maximum at r=0 and a negative minimum at r>0, and (iii) a local maximum at r=0 and a pair maximum-minimum out of the origin. A detailed study of the corresponding properties for individual subshells as well as their relative weight for the total Br is also carried out. For completeness, the analytical Br for hydrogenlike atoms in both ground and excited states is also analyzed.

13.
J Chem Phys ; 120(19): 8906-12, 2004 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-15267826

RESUMEN

A new correlation measure, the product of the Shannon entropy power and the Fisher information of the electron density, is introduced by analyzing the Fisher-Shannon information plane of some two-electron systems (He-like ions, Hooke's atoms). The uncertainty and scaling properties of this information product are pointed out. In addition, the Fisher and Shannon measures of a finite many-electron system are shown to be bounded by the corresponding single-electron measures and the number of electrons of the system.

14.
Int J Legal Med ; 118(4): 197-205, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15114485

RESUMEN

A global study of the sarcosaprophagous community that occurs in the southeastern Iberian Peninsula during all four seasons is made for the first time, and its diversity is described with reference to biological indices. A total of 18,179 adults and, additionally, a number of preimaginal states were collected. The results for the main arthropod groups, and their diversity are discussed in relation to the season and decompositional stages. The results provide an extensive inventory of carrion-associated arthropods. An association between decomposition stages and more representative arthropod groups is established. With respect to the biological indices applied, Margalef's index shows that the diversity of the community increases as the state of decomposition advances, while Sorenson's quantitative index shows that the greatest similarities are between spring and summer on the one hand, and fall and winter, on the other.


Asunto(s)
Artrópodos , Medicina Legal , Cambios Post Mortem , Estaciones del Año , Animales , Cadáver , Pollos , Conducta Alimentaria , España
15.
Cuad. med. forense ; 7(25): 65-73, jul. 2001.
Artículo en Es | IBECS | ID: ibc-10233

RESUMEN

Dada la importancia y creciente utilización de las evidencias entomológicas en la práctica forense, este trabajo propone un protocolo para la adecuada recogida, conservación y remisión de muestras entomológicas para su inclusión en la rutina médico-legal.La utilización de este protocolo permitirá la obtención de una base de datos homogénea y per-fectamente extrapolable a otros casos en el área geográfica (AU)


Asunto(s)
Humanos , Entomología , Medicina Legal/métodos , Calidad del Agua , 35170
16.
Int J Legal Med ; 114(3): 156-62, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11296887

RESUMEN

We present the results of the first study concerning Diptera carried out on the sarcosaprophagous fauna of southeastern Spain. This work represents the first attempt to describe dipteran sarcosaprophagous fauna in the Iberian peninsula, the seasonal succession, main features of the population dynamics and the main taxa useful for estimation of the post-mortem interval. The results of this study could be very useful for further forensic case work in the west Mediterranean area.


Asunto(s)
Autopsia , Cadáver , Dípteros , Entomología , Animales , Pollos , Dípteros/clasificación , Femenino , Humanos , Estadios del Ciclo de Vida , Masculino , Dinámica Poblacional , Estaciones del Año , España
17.
J Trace Elem Med Biol ; 14(2): 81-3, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10941717

RESUMEN

We investigated the effect of lithium chloride administration (Sigma): 1 mmol/kg b.w. i.p./day for 35 days on the testes and sperm of viscacha (Lagostomus maximus maximus), a nocturnal rodent found only in the pampas of Argentina. The histological study showed that hypospermatogenesis and the sperm number per mL decreased markedly in comparison with the controls (treatment group: 315 x 10(6) +/- 77 x 10(6); control group: 693 x 10(6) +/- 39 x 10(6), Means +/- SEM, Student's t-test: p < 0.05). The sperm motility and viability were also affected. Under the same treatment, the testicular tissue and the sperm of rats were not damaged. Moreover, lithium induced these changes when the plasm levels were within the therapeutic range in humans. Our results provide evidence for the claim that viscacha testes and sperm react very sensitively to low doses of lithium, whereas these concentrations do not produce damage in rats.


Asunto(s)
Litio/farmacología , Espermatozoides/efectos de los fármacos , Testículo/efectos de los fármacos , Animales , Masculino , Ratas , Ratas Wistar , Roedores , Motilidad Espermática/efectos de los fármacos , Espermatozoides/metabolismo , Testículo/metabolismo , Testículo/patología
18.
Rev. Soc. Esp. Dolor ; 7(supl.2): 5-10, 2000. graf, ilus
Artículo en Español | IBECS | ID: ibc-155154

RESUMEN

La existencia de receptores específicos para las diferentes sensaciones, a excepción de los receptores específicos para el dolor, era ya conocida desde principios del siglo XIX. Será a lo largo de las últimas décadas del siglo XX cuando el conocimiento de la neuroanatomía y neurofisiología del dolor progrese de forma paralela al desarrollo de nuevos fármacos. El estímulo nociceptivo iniciado en uno de sus receptores será vehiculizado mediante unas fibras nerviosas hacia el asta dorsal de médula, la cual modulará y transformará ese impulso, bien eliminándolo o amplificándolo, para enviar información a través diversos haces nociceptivos: espinotalámico, espinomesencefálico, sistema motor y simpático, hacia centros superiores del córtex donde tendrá lugar la percepción y localización concreta del dolor (AU)


The existence of different sensation-specific receptors, except pain-specific receptors, was already known since the early 19t h century. During the past decades of the 20th century, knowledge of the neuroanatomy and neuro physiology of pain started to progress in parallel to the development of new drugs. Nociceptive stimulus initiated in one of such receptors is transmitted through some nervous fibers to the medullar dorsal horn, where such impulse is eliminated or amplified in order to send information through different nociceptive pathways æspinothalamic, spinomesencephalic, motor and sympathetic systemæ towards the upper centers of the cortex, where the specific perception and localization of pain takes place (AU)


Asunto(s)
Humanos , Masculino , Femenino , Neuroanatomía/métodos , Dolor/complicaciones , Dolor/tratamiento farmacológico , Nociceptores , Asta Dorsal de la Médula Espinal , Nervios Periféricos , Médula Espinal , Médula Espinal/patología , Neuronas , Neuronas/patología
19.
Rev. Soc. Esp. Dolor ; 7(supl.2): 11-17, 2000. tab
Artículo en Español | IBECS | ID: ibc-155155

RESUMEN

La transmisión nociceptiva experimenta una compleja modulación desde la génesis del impulso nervioso a nivel periférico hasta su percepción como sensación dolorosa. Se conocen algunos neurotransm isores implicados en la sensibilización e inhibición de los nociceptores que determinan la aparición clínica del dolor. Además, las neuronas del asta dorsal participan en la modulación e integración del dolor hacia centros superiores. Durante la transmisión y/o neuromodulación existen unos cambios bioquímicos agrupados en tres niveles: periférico, medular y central (AU)


The nociceptive transmission shows the complex modulation from the start of the peripheral impulse until its final pain perception. It has been recognized that some neurotransmisors seem to be important in sensibilization and inhibition phenomena when pain occurs. Also, the dorsal horn plays an important part in the modulation and integration of pain in the upward travel to central centres. During modulation biochemical changes take part, these modifications are included at different levels: peripheral, medullar and central (AU)


Asunto(s)
Humanos , Masculino , Femenino , Neurofisiología/instrumentación , Neurofisiología/métodos , Dolor/fisiopatología , Nociceptores , Nociceptores/fisiología , Receptores de Neurotransmisores/análisis , Neurotransmisores/fisiología , Fibras Nerviosas/fisiología , Enfermedades del Sistema Nervioso/complicaciones , Enfermedades del Sistema Nervioso/fisiopatología , Neuronas Motoras/fisiología , Corteza Cerebral , Corteza Cerebral/fisiopatología
20.
Phys Rev A ; 50(1): 256-266, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9910890
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