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Supplemental Digital Content is available in the text.De novo malignancies (DNMs) following liver transplantation (LT) have been reported as 1 of the major causes of late mortality, being the most common cause of death in the second decade after LT. The overall incidence of DNMs is reported to be in the range of 3.1% to 14.4%, and the incidence is 2- to 3-fold higher in transplant recipients than in age- and sex-matched healthy controls. Long-term immunosuppressive therapy, which is the key in maintaining host tolerance and achieving good long-term outcomes, is known to contribute to a higher risk of DNMs. However, the incidence and type of DNM also depends on different risk factors, including patient demographics, cause of the underlying chronic liver disease, behavior (smoking and alcohol abuse), and pre-existing premalignant conditions. The estimated standardized incidence ratio for different DNMs is also variable. The International Liver Transplantation Society–Spanish Society of Liver Transplantation Consensus Conference working group on DNM has summarized and discussed the current available literature on epidemiology, risk factors, management, and survival after DNMs. Recommendations for screening and surveillance for specific tumors, as well as immunosuppression and cancer-specific management in patients with DNM, are summarized.

[Display omitted] • Amorphous WO 3-x is grown by DC sputtering, with x controlled by the oxygen pressure. • The most oxidized films show interband absorption at E g = 3.37 eV and N ∼ 1015 cm−3. • For 0 < x ≤ 0.2, W5+ states increase absorption at 1.5 eV and the electron density. • For x > 0.2, W4+ states produce absorption at 3.3 eV but no higher electron density. Tungsten oxides are interesting for a variety of applications due to their versatile optoelectronic characteristics, which can be tuned changing the composition and/or the crystalline structure. Coloration due to sub-bandgap absorption is often achieved by ion intercalation or doping in WO 3 :M films (with M = H+, Li+, Na+, etc. introducing extra electrons), but a more direct way is creating charged oxygen vacancies (V O + and/or V O 2+) in sub-stoichiometric WO 3- x forms. Here, amorphous WO 3- x thin films are obtained by reactive DC sputtering of a pure W target, on unheated glass substrates, changing the oxygen to argon pressures ratio. The control of intrinsic defects (oxygen vacancies and tungsten valence states) by the oxygen partial pressure allows tuning the morphology, sub-bandgap absorption and carrier density in these WO 3- x films, as it is proven by Raman spectroscopy, atomic force microscopy, optical spectrophotometry and Hall effect measurements. [ABSTRACT FROM AUTHOR]

In recent decades, the field of female fertility preservation has experienced substantial growth. Reliable techniques such as cryopreservation of oocytes and ovarian tissue have emerged, along with more established methods such as embryo freezing. Among the group of patients who can benefit from these new techniques are patients with endometriosis, a common disease capable of compromising ovarian reserve and fertility prospects. Unfortunately, comprehensive recommendations for fertility preservation in patients with endometriosis are still lacking.

The methods for gypsum content determination in soils are summarized and their applicability discussed. Special attention is given to the critical step of sample preparation, stressing the elimination of the oven heating at temperatures surpassing 40°C. Wet methods are unsuitable for soils rich in gypsum or containing other sulfates. Instead, oven‐based methods playing on the mass variations due to the release of constitutional water of gypsum are preferable. Under laboratory settings, we recommend two existing methods: one directly measuring the loss of mass on heating and the other exploiting the gypsum–bassanite phase change under controlled conditions. Both reflectance and X‐ray fluorescence (XRF) provide nondestructive methods for quick gypsum appraisal, and combining both methods increases the accuracy. The results are easily calibrated with gravimetric methods.

La sobrecarga asistencial y los cambios organizativos frente a la pandemia de COVID-19 podrían estar repercutiendo en la atención al ictus agudo en la Comunidad de Madrid.

La pandemia por COVID-19 ha obligado a una reorganización de los sistemas sanitarios y ha comportado una saturación excepcional de sus recursos. En este contexto es vital asegurar la atención al ictus agudo y optimizar los procesos asistenciales del código ictus para reducir el riesgo de contagios y racionalizar el uso de recursos hospitalarios. Para ello, desde el Grupo Multidisciplinar Ictus Madrid proponemos una serie de recomendaciones.

SnO is an ideally suitable p-type conductive material, with large hole mobility, and has attracted great interest in connection with next-generation electronic applications. In the present work, tin oxide (SnO x) thin films were deposited on unheated soda lime glass substrates by reactive DC sputtering from a pure Sn target. The structural, optical and electrical properties of the films were analysed as a function of the oxygen partial pressure in the sputtering atmosphere and of the post-deposition annealing temperature in air. A structural analysis was carried out using Raman spectroscopy and X-ray diffraction. Optical and electrical characterizations were performed using photo-spectrometry and Hall effect measurements, respectively. The films grown at room temperature and low oxygen pressures reached high deposition rates of above 45 nm/min, showing poorly crystalline SnO and low transparency. Subsequent heating to 350 °C allowed to achieve a more crystalline tetragonal SnO with an average visible transmittance of 65%, a p-type conductivity of 0.8 S/cm, and a hole mobility of 3.5 cm2/(V s). [ABSTRACT FROM AUTHOR]

Describir los cuidados proporcionados al final de la vida en los pacientes fallecidos en servicios de medicina interna.

In recent years, big efforts have been dedicated to identify which are the factors with highest influence in the energy consumption of residential buildings. These factors include aspects such as weather dependence, user behaviour, socio-economic situation, type of the energy installations and typology of buildings. The high number of factors increases the complexity of analysis and leads to a lack of confidence in the results of the energy simulation analysis. This fact grows when we move one step up and perform global analysis of blocks of buildings. The aim of this study is to report a new methodology for the assessment of the energy performance of large groups of buildings when considering the real use of energy. We combine two clustering methods, Generative Topographic Mapping and k-means, to obtain reference dwellings that can be considered as representative of the different energy patterns and energy systems of the neighbourhood. Then, simulation of energy demand and indoor temperature against the monitored comfort conditions in a short period is performed to obtain end use load disaggregation. This methodology was applied in a district at Terrassa City (Spain), and six reference dwellings were selected. Results showed that the method was able to identify the main patterns and provide occupants with feasible recommendations so that they can make required decisions at neighbourhood level. Moreover, given that the proposed method is based on the comparison with similar buildings, it could motivate building occupants to implement community improvement actions, as well as to modify their behaviour.

The recent COVID-19 outbreak has led health authorities to recommend at least the use of surgical masks, most preferably respirators (FFP2 or KN95), to prevent the spread of the virus. Non-woven fabrics have been chosen as the best option to manufacture the face masks, due to their filtration efficiency, low cost, and versatility. Modifying the mask filters with graphene has been of great interest due to its potential use as antibacterial and virucidal properties. Indeed, some companies have commercialized face masks in which graphene is coated and/or embedded. However, the Canadian sanitary authorities advised against using the Shandong Shengquan New Materials Co. graphene masks because of the possibility of pulmonary damage produced by graphene inhalation. Thus, we have analyzed the stability of the graphene filter of these masks and compared it with two other commercially available graphene mask filters, evaluating the morphological and spectroscopical change of the fibers, as well as the particles released during the endurance tests. Our work introduces the necessary tools and methodology to evaluate the potential degradation of face masks under extreme working conditions. These methods complement the present standard tests ensuring the security of the new filters based on composites or nanomaterials.

La interconsulta médica en pacientes hospitalizados constituye una actividad habitual entre los especialistas en medicina interna. Sin embargo, a pesar de su impacto e importancia crecientes, no se ha establecido un modelo que defina sus características, sus objetivos o la información que debe contener. En este trabajo, desde el Grupo de Asistencia Compartida e Interconsultas de la Sociedad Española de Medicina Interna, se proponen unas recomendaciones generales respecto a la forma de solicitar y de responder una interconsulta médica hospitalaria, así como un formato para la misma.

This multicenter study analyzes the outcome of patients transplanted for hepatocellular carcinoma who were found to have an intrahepatic cholangiocarcinoma at pathology examination, and focuses on the excellent posttransplant outcome of patients with single intrahepatic cholangiocarcinomas ≤2 cm.

The chamois Rupicapraspp. is the most abundant mountain ungulate of Europe and the Near East, where it occurs as two species, the northern chamois R. rupicapraand the southern chamois R. pyrenaica. Here, we provide a state‐of‐the‐art overview of research trends and the most challenging issues in chamois research and conservation, focusing on taxonomy and systematics, genetics, life history, ecology and behavior, physiology and disease, management and conservation. Research on Rupicaprahas a longstanding history and has contributed substantially to the biological and ecological knowledge of mountain ungulates. Although the number of publications on this genus has markedly increased over the past two decades, major differences persist with respect to knowledge of species and subspecies, with research mostly focusing on the Alpine chamois R. r. rupicapraand, to a lesser extent, the Pyrenean chamois R. p. pyrenaica. In addition, a scarcity of replicate studies of populations of different subspecies and/or geographic areas limits the advancement of chamois science. Since environmental heterogeneity impacts behavioral, physiological and life history traits, understanding the underlying processes would be of great value from both an evolutionary and conservation/management standpoint, especially in the light of ongoing climatic change. Substantial contributions to this challenge may derive from a quantitative assessment of reproductive success, investigation of fine‐scale foraging patterns, and a mechanistic understanding of disease outbreak and resilience. For improving conservation status, resolving taxonomic disputes, identifying subspecies hybridization, assessing the impact of hunting and establishing reliable methods of abundance estimation are of primary concern. Despite being one of the most well‐known mountain ungulates, substantial field efforts to collect paleontological, behavioral, ecological, morphological, physiological and genetic data on different populations and subspecies are still needed to ensure a successful future for chamois research and conservation.

Non‐trodden soils free of human and livestock pedestrian activity occur on the floors of hypersaline playa‐lakes in the Monegros' inland wetlands in Spain. A soil surface vesicular crust (herein designed as A1v horizon) organized in decimetric polygonal plates is the main observable feature of these rare soils inhabited by the perennial halophyte shrub Arthrocnemum macrostachyum(Moric.) Moris (A.m.). The vesicular organization of the A1v, together with its discontinuity with the soil underneath, suggests the existence of two contrasting soil microenvironments. Thirty‐three sites of seven wetlands inhabited by A.m.were sampled: the A horizon from 0 to 15 cm, that is, including A1v; and separately the A1v and the underneath A2 horizon up to 15‐cm depth. Measurements included Munsell color, moisture, and salinity at different soil/water ratios, during both the dry and wet seasons along with determinations of gypsum content, calcium carbonate equivalent, and organic matter. Evidence of the mulching effect of A1v and its contrasting conditions against the underlying A2 is supported by the significant differences in 1:5 soil/water extracts electrical conductivity, with a July mean EC1:5 of 22.3 dS m−1in A1v vs. 14.0 dS m−1in A2, and by similar significant differences in all major ions, except Ca. In July, total dryness (0%) can be achieved by A1v whereas A2 retained some moisture (5% minimum). Significant moisture differences were found for A1v and A2 in December together with a homogenizing effect. These are significant traits to be considered both in halophyte germination and establishment studies, and in ecological and restoration plans.

Indium sulfide thin films were successfully deposited on soda lime glass substrates by modulated flux deposition (MFD) at significantly lower substrate temperatures than in previous experiments. The influence of both experimental parameters sulfur source temperature (TS) and substrate temperature (T) on the optical, structural, and chemical properties were studied. Amorphous indium sulfide layers were obtained at T= 100 °C and crystallized as β‐In2S3for T≥ 150 °C. Quite high values were required for the TSparameter in order to ensure the formation of transparent β‐In2S3thin films. No other polycrystalline phases were detected. Direct optical bandgaps of 2.58 eV (amorphous In2S3) and 2.73 eV (β‐In2S3) were estimated for film thicknesses of around 100 nm.

CuAlxGa1−xSe2(CAGS) is an attractive wide‐bandgap chalcopyrite for buffer and top cell in tandem solar cells avoiding the use of expensive In. Polycrystalline CAGS thin films with chalcopyrite structure and strongly oriented along the (112) plane have been obtained by a sequential process of vacuum evaporation and selenization, with different xvalues ranging from 0 to 1. The temperature of selenization has been varied between 450 and 550 °C and it has resulted on a critical parameter in the complete and homogeneous formation and crystalline quality of the CAGS thin films. The proportion of Al(x) also affects the temperature required for selenization. At least 500 °C is necessary to obtain complete formation of CAGS for x> 0.1 whereas for x≤ 0.1 the formation takes place in a wide range of annealing temperatures. Resistivity, roughness, band gap energy, texture coefficient C112and crystallite size tend to increase as the selenization or annealing temperature increases. CAGS thin film properties are optimized at 525 °C for high Al proportions for which some deterioration proceeded at higher temperatures whereas at low Al proportions, a similar behaviour for 525 and 550 °C is observed.

Tin selenide thin films have been prepared by selenization of sputtered tin layers and have been analyzed comparatively onto bare and SnO2‐coated glass substrates. In particular, the effects of the selenization temperature and the polycrystalline substrate nature on the stoichiometry and physical properties of the layers were investigated. X‐ray diffraction was used to determine the crystalline phases and their structure, scanning electron microscopy to observe the surface topography, energy‐dispersive X‐ray analysis to establish the film composition, and spectrophotometry to determine the optical absorption, all these properties correlated to the experimental parameters. By using polycrystalline tin oxide coatings it is possible to achieve a significant crystalline enhancement for the SnSe and SnSe2phases identified, being the Se:Sn atomic proportion, as well as the optical absorption, highly dependent on the selenization temperature apart from the substrate nature.

Mechanical properties of biological molecular aggregates are essential to their function. A remarkable example are double-stranded DNA viruses such as the φ29 bacteriophage, that not only has to withstand pressures of tens of atmospheres exerted by the confined DNA, but also uses this stored elastic energy during DNA translocation into the host. Here we show that empty prolated φ29 bacteriophage proheads exhibit an intriguing anisotropic stiffness which behaves counterintuitively different from standard continuum elasticity predictions. By using atomic force microscopy, we find that the φ29 shells are approximately two-times stiffer along the short than along the long axis. This result can be attributed to the existence of a residual stress, a hypothesis that we confirm by coarse-grained simulations. This built-in stress of the virus prohead could be a strategy to provide extra mechanical strength to withstand the DNA compaction during and after packing and a variety of extracellular conditions, such as osmotic shocks or dehydration.

Transparent electrodes based on very thin stacked layers of Aldoped zinc oxide AZO and Ag have been prepared on conventional soda lime glass and flexible polyethylene terephthalate substrates by sputtering at room temperature. The optical, electrical and structural characteristics of AZOAgAZO multilayer electrodes have been analysed at different preparation stages and compared onto glass and polymer substrates. Such structures have shown sheet resistance below 6 Ω sq−1and maximum transmittance around 85 near 600 nm by discounting the corresponding substrate, with a low material consumption owing to the whole electrode thickness is below 100 nm. The band gap energy has been found dependent on the structural distortion of the asgrown polycrystalline AZO films, being both parameters higher on the polymer than on the glass substrates.

The familiarity of mankind with gypsum and its simple composition are in contrast with the frequent mistakes reported for its behavior and role in nature. Gypsum has been studied as a raw material, as a rock constituent, as an indicator of geological and archaeological conditions, and from other points of view. However, its role in Earth surface processes, its relationship to life through calcium in the equilibrium of carbonates and its structural water molecules, seems overlooked. Moreover, errors of gypsum formulation, analysis, and behavior obscure some of its roles within nature. The semi‐solubility of gypsum explains its actions in many soils. The softness, fragility, and crystal water of gypsum are often not considered. Routinely drying at 105°C and pulverizing samples for lab analyses casts suspicion on all analytical results because gypsum becomes anhydrite and/or bassanite at this temperature. Specific physicochemical models are needed to predict the behavior of soils mainly composed of gypsum.

Transparent and conductive Aldoped ZnO AZO films with thickness between 0.2 and 1.1 μm were deposited by sputtering at room temperature on glass and polyethylene terephthalate PET substrates. All films were polycrystalline with average crystallite size increasing when the film thickness was increased, being smaller for the layers grown on PET, which showed also a higher lattice distortion. For a same thickness, the optical band gap energy is found higher for the AZO layers deposited on PET, and such variation is related to the corresponding structural distortion. Besides, carrier mobility is found increasing and resistivity decreasing when the film thickness was increased, achieving a minimum value of 1.6 mΩ cm on glass and PET samples. An inverse relationship between the free carrier concentration and the mobility has been established, applying to the films grown on both substrates. With the thickest AZO layers, sheet resistance below 15 Ω sq–1and average visible transmittance about 85 have been obtained by sputtering at room temperature on glass and PET substrates. © 2009 WILEYVCH Verlag GmbH & Co. KGaA, Weinheim

Avian Plasmodium and Haemoproteus parasites are easily detected by DNA analyses of infected samples but only correctly assigned to each genus by sequencing and use of a phylogenetic approach. Here, we present a restriction site to differentiate between both parasite genera avoiding the use of those analyses. Alignments of 820 sequences currently listed in GenBank encoding a particular cytochrome B region of avian Plasmodium and Haemoproteus show a shared restriction site for both genera using the endonuclease Hpy CH4III. An additional restriction site is present in Plasmodium sequences that would initially allow differentiation of both genera by differential migration of digested products on gels. Overall 9 out of 326 sequences containing both potential restriction sites do not fit to the general rule. We used this differentiation of parasite genera based on Hpy CH4III restriction sites to evaluate the efficacy of 2 sets of general primers in detecting mixed infections. To do so, we used samples from hosts infected by parasites of both genera. The use of general primers was only able to detect 25% or less of the mixed infections. Therefore, parasite DNA amplification using general primers to determine the species composition of haemosporidian infections in individual hosts is not recommended. Specific primers for each species and study area should be designed until a new method can efficiently discriminate both parasites. [ABSTRACT FROM AUTHOR]

The presence of gypsum in soil, even in small amounts, is relevant from the genetic, taxonomic, and applied points of view. Moreover, those soils having gypsum as the main component, for example gypseous soils, host a number of rare and endangered organisms. Determining gypsum content in soils is crucial to understanding their behavior; however, current methods of determination are cumbersome or imprecise. This study was conducted to develop an accurate new method to determine soil gypsum content by reducing the inaccuracies or poor assumptions in previous methods. We determined gypsum content in samples using quartz sand and clay minerals mixed with gypsum reagent powder to 0 and approximately 2, 5, and 50% gypsum content; we also studied seven gypseous soil samples. Gypsum (CaSO4·2H2O), after heating at 105°C, dehydrates, losing the two water molecules of the gypsum crystal cell and becoming mostly anhydrite (CaSO4). Anhydrite is very hygroscopic, absorbing atmospheric water very quickly; this process has been found to occur even in desiccators where the relative humidity (RH) is between 12 and 20% depending on the desiccant. Anhydrite rehydrates under laboratory conditions to bassanite (CaSO4·0.5H2O), which is stable at RH values <100%. We propose exploiting this difference in mass between gypsum and bassanite to quantify the gypsum content of soils. We found that by equilibrating the soils at constant RH, e.g., 40%, before and after heating the samples, the clay water content is constant, eliminating a major error with other thermogravimetric methods. This simple, yet effective method determined gypsum content to within 1% in all the mineralogies studied, whereas other oven‐based methods overestimated gypsum content by as much as 36% in a pure Ca‐montmorillonite sample.

Many land use decisions are made without the aid of soil maps in countries without National soil surveys. The purpose of this research was to create a soil survey delineating salinity phases at a regional scale that could serve as the basis for improved decision making, or highlight areas for further investigation. Soil salinity survey at a regional scale remains a challenge. We demonstrate a survey methodology suited to small fields, often found in Europe and developing countries, and present a streamlined survey methodology making this typically labor‐intensive process more efficient. A regional soil survey was conducted at a scale of 1:25 000, mapping consociations and complexes of soil series. The soil survey information was then used to guide an electromagnetic induction (EMI) survey of the soils with observed salinity, to delineate phases. A calibration method for estimating the electrical conductivity of the extract of the saturated paste (ECe) from the EMI measurements was devised. After testing several statistical methods, a single calibration of the EMI data was found to be suitable using a nonparametric regression. The use of the EMI method reduced operation costs, where time, personnel, analysis time, and budget are limitations.

Determining the gypsum content in soil is lengthy and cumbersome using methods based on SO4determination. Moreover, as these methods do not strictly titrate gypsum, inaccuracies can be produced by the presence of sulfate minerals other than gypsum. The thermogravimetric properties of gypsum, however, allow determination of its content in a rapid and easy way sufficiently accurate for many pedologic purposes. Our objective was to expand the lower limit of gypsum detection to make the test useful for soil classification and management. We have refined the differential water loss method by estimating the gypsum percentage from the loss of water in the soil sample between 70 and 90°C. Our results, compared with gravimetric determinations of precipitated BaSO4, found coefficients of determination of 0.98 for gypsum contents ranging from 2 to 50%, and 0.99 for contents >50%. The method is valid for gypsum contents >2% and thus improves previous estimation procedures.

Copper indium sulphide and copper gallium sulphide thin films have been prepared using a novel modulated flux deposition process from elemental evaporation sources that were adjusted to give different cation (Cu/In or Cu/Ga) ratios ranging from 0.6 to 1.4. The crystalline structure and optical properties of the samples, as determined by X-ray diffraction and spectrophotometry, have been analysed as a function of the overall composition. Also, the atomic distribution in the film depth has been obtained by combining X-ray photoelectron spectroscopy and Ar+ sputter etching. An increase in copper content leads to an increase of the average crystallite size and a decrease of the structural stress, and an increase of the absorption coefficient at low energies. These effects are more pronounced for the copper gallium sulphide than for the copper indium sulphide samples for the preparation conditions used. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

An introduction to conductance atomic force microscopy in the context of carbon nanotubes is provided where the main problems and performances of this technique are discussed. The conductance measured in SWNT as a function of the loading force applied by an AFM metallized tip is reported. These experiments allow us to study the process of the electrical contact formation between the tip and the nanotube. This will also lead to a study of the electromechanical properties of nanotubes for radial deformations.An introduction to conductance atomic force microscopy in the context of carbon nanotubes is provided where the main problems and performances of this technique are discussed. The conductance measured in SWNT as a function of the loading force applied by an AFM metallized tip is reported. These experiments allow us to study the process of the electrical contact formation between the tip and the nanotube. This will also lead to a study of the electromechanical properties of nanotubes for radial deformations.

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In this article, the effect of sample size on the degassing behavior of closed‐cell low density polyethylene (LDPE) foam under long‐term compressive static loading is presented. The creep response was modeled by assuming isothermal compression of the gas. The change in gas pressure with time was obtained and the effective diffusion coefficients were calculated from pressure decrease using an analytical solution of the diffusion equation, and were found to increase when the sample size was reduced. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci, 2006

Treatment with insulin-sensitizing agents is a relatively recent therapeutic strategy in women with polycystic ovary syndrome (PCOS) and insulin resistance. The key areas addressed in this review include PCOS and the development of type 2 diabetes mellitus and gestational diabetes, as well as the use of insulin-sensitizing agents, particularly metformin, in the management of infertility in obese and non-obese PCOS women. Treatment with metformin in PCOS women undergoing IVF and the use of metformin during gestation will be discussed. The challenge for the health care professional should be the appropriate utilization of pharmacotherapies to improve insulin sensitivity and lower circulating insulin levels resulting in beneficial changes in PCOS phenotype. Further research into the potential role of other insulin-sensitizing agents, such as pioglitazone and rosiglitazone, in the treatment of infertile women with PCOS is needed.

Complexes RhCl(PPh3)3 and RhH2Cl(PⁱPr3)2 catalyze the dehalogenation of γ-hexachlorocyclohexane to benzene and the simultaneous chlorination of HSiEt3 to ClSiEt3. In the presence of RhCl(PPh3)3, the dehalogenation is inhibited by addition of PPh3. ¹H and ³¹P{¹H} NMR spectroscopy studies at variable temperature, on the behavior of the complex RhCl(PPh3)3 in the presence of γ-hexachlorocyclohexane and/or HSiEt3, indicate that the catalytic reaction involves the initial interaction of the catalyst with the silane and that chloro−hydride intermediates related to RhH2Cl(PPh3)3 are the main species during the catalysis. The complexes RuHCl(PPh3)3, RuH2Cl2(PⁱPr3)2, and RuHCl(η²-H2)(PⁱPr3)2 also catalyze the dehalogenation of γ-hexachlorocyclohexane and the simultaneous chlorination of HSiEt3 to ClSiEt3. In these cases, the dehalogenation products are 6/4 cyclohexene/cyclohexane (RuHCl(PPh3)3) and 4/6 cyclohexene/benzene (RuH2Cl2(PⁱPr3)2 and RuHCl(η²-H2)(PⁱPr3)2) mixtures. The dehalogenations of α- and δ-hexachlorocyclohexane catalyzed by RhCl(PPh3)3, RhH2Cl(PⁱPr3)2, and RuHCl(PPh3)3 have been also investigated. The initial rates for the formation of ClSiEt3 decrease in the sequence γ- > α- > δ-hexachlorocyclohexane.

Objective and design:To study the involvement of all-trans retinoic acid (ATRA) in the development and maintenance of inflammatory pain. Subjects:Adult male Wistar rats and murine neuro2a and human SH-SY5Y neuroblastoma cells. Treatment:Soft-tissue inflammation was induced by the intraplantar administration of 100 μl of carrageenan λ. The oral treatment with either ATRA or vehicle lasted for seven days and consisted in a dose of 15 mg/kg the first two days and a dose of 10 mg/kg the following five days. Neuroblastoma cells were incubated for 16 h with ATRA. Methods:Rats were tested twice daily for intensity and evolution of withdrawal reflexes evoked by mechanical and thermal stimulation. The expression of COX enzymes was studied in spinal cords and neuroblastoma cells by western blot. Results:The animals treated with ATRA showed a significantly more intense development of mechanical allodynia (p < 0.01), mechanical hyperalgesia (p < 0.01), thermal hyperalgesia (p < 0.001) and reduction of threshold for mechanical (29 ± 4 vs. 60 ± 6 mN, p < 0.001) and thermal stimulation (12 ± 0.3 vs. 8.4 ± 0.3 s, p < 0.001) than control animals. Recovery to mechanical baseline data was slower in animals treated with ATRA, the main difference was observed in the test carried out on day 2, p.m. In neuroblastoma cells incubated with ATRA, a concentration-dependent increase in the expression of COX-2 protein was observed. Changes in the expression of COX-1 enzyme were not clear. An increase in COX-2 expression in the lumbar spinal cord was also observed in animals treated with ATRA. Conclusions:A clear relationship between the oral administration of ATRA and an enhancement of the nociceptive withdrawal reflexes was observed in rats. This relationship was associated with an increment of the expression of the COX-2 enzyme.

Older age is not considered a contraindication for liver transplantation, but age-related morbidity may be a cause of mortality. Survival and the incidence of the main post-transplant complications were assessed in 111 adult liver transplant recipients. They were divided in two groups according to their age (patients younger than 60 years, n=54; patients older than 60 years, n=57) and both groups were compared. Older patients were more frequently transplanted for hepatitis C (p= 0.03) and hepatocellular carcinoma (p= 0.05) and their liver disease was less advanced (Child-Pugh and MELD scores were significantly lower; p=0.004 and p=0.05, respectively). After transplantation, older patients had a significantly lower survival (p=0.02). Higher age was independently associated with mortality (hazard ratio for each 10-year increase: 2.1; 95% confidence interval: 1.1- 4.0; p=0.02). The incidence of de novoneoplasia and nonskin neoplasia were higher in older patients (p=0.02 and p =0.007, respectively). Malignancy was the cause of death in one patient younger than 60 years and in 12 patients older than 60 years (p =0.002). In multivariate analysis, a higher age and smoking were independently associated with a higher risk of dying of de novoneoplasia. In conclusion, older liver transplant recipients have a significantly lower survival than younger patients. Malignancy is responsible for this decreased survival.

An analytically-based, computationally simple methodology is presented for calculating the velocity components of air flowing normal and parallel to a pair of suspensions attached to an E-block in a hard disk drive. The analysis allows for arbitrary angular orientation of the E-block/suspensions unit and accounts for the flow blockage due to the portion of the E-block that penetrates the inter-disk space. It is found that, for fixed orientation angle and disk speed of rotation, the velocity component parallel to a suspension is constant and positive everywhere along its length. In contrast, the velocity component normal to a suspension is a decreasing linear function of its length, from base to tip, and can change sign. The ratio of normal to parallel velocity components shows that the latter is generally significantly larger than the former along the entire length of a suspension for practical operating conditions. The expressions derived should be of value to the industry for the analysis and improved design of E-block/suspensions units in hard disk drives.

The weathering of lutites in aridic or near‐aridic environments leading to soil horizons is not well known. Lutites are a common soil parent rock composed of silt and clay, that may be massive or may have their sedimentary origin marked by layers of alternating color or granulometry, or by fissility along planes. Lutites underlying soils are considered Cr horizons and show different alteration stages recognizable in the field by the degree of the layering disturbance or by the loss of coherence. In the study area, neither the dry climate nor the kind of clay minerals, mainly illite, can explain the weathering of lutites. This study was conducted to investigate the initial weathering reactions as encountered in Cr horizons, and to depict the processes responsible for pedogenesis from lutites in gypsiferous soils of the Ebro Valley (Spain). We described 12 soils in the field under two different soil moisture regimes, with further characterization through chemical analyses and micromorphology by thin section and scanning electron microscope (SEM). The microscopic study revealed two distinctive pedofeatures in the Cr horizons: (i) lenticular gypsum crystals; and (ii) “queras,” sub‐millimetric biotic features produced by calcification‐decalcification processes. Growth of gypsum crystals in these horizons resulted in an “isles fabric,” that is, isles of fine materials in a mass of gypsum crystals, with much greater porosity than the parent lutite. The growth of gypsum crystals and the development of queras result in a particle‐size distribution change and an increased porosity of the Cr horizons.

In the present work the electrostatic interaction of a real scanning force microscopy (SFM) probe with a sample is studied theoretically as well as experimentally. To model the probe, a complex system composed of a macroscopic cantilever, a mesoscopic tip cone and a nanometric tip apex is proposed. The corresponding interaction is calculated analytically by means of an appropriate approximation. In most experimental situations we find that the total interaction is dominated by the cantilever and/or the tip cone and not by the tip apex. Experimental determination of tip–sample interaction supports this model. In addition, we find that a real SFM probe may lead to misinterpretation of experimental data in the so-called Kelvin probe microscopy (KPM). Again, experimental data confirm that the effects described by the model we propose may induce severe errors in KPM. As shown in this work, the resolution in KPM and electrostatic force microscopy is dramatically enhanced and data interpretation simplified if the force gradient rather than the force is used as signal source for the electrostatic interaction.

In this work we present two scanning force microscopy (SFM) techniques applied to the electrical characterization of V₂O₅ nanofibres with one end connected to a metallic electrode: first a non-contact imaging technique combined with the acquisition of current versus voltage curves in a selected spot, and second jumping mode SFM that allows simultaneous acquisition of topograhic images and current maps with nanometric resolution. Both the conductivity (~20 S cm⁻¹) and the contact resistance (~ 62 MΩ) of the fibres are determined. A non-linear behaviour of the conductivity is observed for large applied electrical fields ( 10^{5}~{\rm V~cm}^{-1}$">E > 10⁵ V cm⁻¹) as found previously for V₂O₅ films.

Modified DNA species have attracted the interest of the scientific community in the last years in a search for an appropriate molecular wire for the incoming nanotechnology. M-DNA, a complex of DNA with divalent metallic ions, is one of the candidates for a molecular wire. In this paper we describe the procedure to fabricate M-DNA using NiCl₂ and CoCl₂, and a simple test to check the production of the modified biomolecule. We present atomic force microscope (AFM) images of nickel and cobalt M-DNA. Our results show that the DNA modified with these metal ions suffers a fivefold reduction in length and an increment of almost one order of magnitude in height as compared to the length and height of regular B-DNA. This type of condensation of the DNA is fully reversible upon the addition of EDTA. AFM images of reversed M-DNA show no differences from regular B-DNA. Two types of electrostatic experiment performed on this modified molecule show no evidence for metallic or semiconductor behaviour.

The use of DNA microarrays opens up the possibility of measuring the expression levels of thousands of genes simultaneously under different conditions. Time-course experiments allow researchers to study the dynamics of gene interactions. The inference of genetic networks from such measures can give important insights for the understanding of a variety of biological problems. Most of the existing methods for genetic network reconstruction require many experimental data points, or can only be applied to the reconstruction of small subnetworks. Here we present a method that reduces the dimensionality of the dataset and then extracts the significant dynamic correlations among genes. The method requires a number of points achievable in common time-course experiments. Copyright © 2003 John Wiley & Sons, Ltd.

Management of patients with carcinoma of the larynx should systematically include an appropriate treatment of lymph nodes according to the TNM stage. One of the most controversial points of the treatment in these patients is the management of the clinically negative neck (N0). A retrospective study of 295 patients with laryngeal carcinoma and N0 neck undergoing treatment in our centre between 1983 and 1993 is presented. We observed a significant decrease in the survival of clinically N0 patients with histologically affected lymphnodes. Lymphadenopathy was more frequently detected in patients with supraglottic tumours (38 per cent) when compared to glottic tumours (16 per cent). In our experience, routine bilateral and unilateral dissection of N0 necks in all supraglottic tumours and in T3–T4 glottic tumours, respectively, is the most beneficial approach for patients in terms of survival.

Self-organizing maps (SOM) constitute an alternative to classical clustering methods because of its linear run times and superior performance to deal with noisy data. Nevertheless, the clustering obtained with SOM is dependent on the relative sizes of the clusters. Here, we show how the combination of SOM with hierarchical clustering methods constitutes an excellent tool for exploratory analysis of massive data like DNA microarray expression patterns. Keywords: DNA array, gene expression patterns, hierarchical clustering, SOM, SOTA

A new method for radar measurement bias correction is described. It is based on the use of a mode S datalink and GPS receivers, and may provide accurate bias estimations both for primary and secondary collocated radars. The proposed method distributes effectively the calibration process over the radar network, potentially reducing communication needs and computation complexity of currently used centralised bias estimation methods. The accuracy of the method is analytically predicted, based on measurement error statistics.

Objective: To investigate the effects of repeated cis-dichlorodiamine-platinum (CDDP) exposure on serum erythropoietin (Epo) levels. Study design: In seven patients with ovarian cancer, Epo and haemoglobin concentration (cHb) were measured before, 24h and 7 days after administration of the first three courses of chemotherapy. In seven control patients undergoing gynaecological surgery for non-malignant reasons, Epo and cHbwere measured before, 24h and 7 days after the operation. Results: Following Epo increased, independent of concomitant anaemia, especially after the third course: 51mU/ml (S.D. 46) versus 122mU/ml (S.D. 83) (P=0.02). In the control patients, Epo was lower although the decrease of cHbwas significantly higher. Conclusion: Cis-platinum chemotherapy induces an increase in erythropoietin levels independent of anaemia. The underlying mechanism remains to be investigated.

Vascular access complications are the main cause of hospitalization in dialysis patients. The difficulty in creating and maintaining vascular access after several years on haemodialysis (HD) remains the primary problem in these patients. The femoro-femoral Thomas shunt is a permanent vascular access that was used in the 1970s and is all but forgotten at present. We analysed our experience with the Thomas shunt since 1979 in patients with no other possibility of regular vascular access.

Complex OsHCl(CO)(PⁱPr3)2, in the presence of diethylamine, catalyzes the dimerization of terminal alkynes HC&tbd1;CR (R = Me3C, Cy, Ph, and Me3Si). The reactions initially give butatrienes RCH&dbd;C&dbd;C&dbd;CHR, which are stable under the reaction conditions for R = Me3C and Cy. For R = Ph, the butatrienes polymerize to −[CH(Ph)C&tbd1;CCH(Ph)]n−, while for R = Me3Si, the butatriene isomerizes into the enyne Z−Me3SiCH&dbd;CH−C&tbd1;CSiMe3. The formation of butatrienes takes place via butenynyl intermediates of the type Os(C&tbd1;CR){η³-C(C&tbd1;CR)&dbd;CHR}(CO)(PⁱPr3)2.

We describe a new approach to the analysis of gene expression data coming from DNA array experiments, using an unsupervised neural network. DNA array technologies allow monitoring thousands of genes rapidly and efficiently. One of the interests of these studies is the search for correlated gene expression patterns, and this is usually achieved by clustering them. The Self-Organising Tree Algorithm, (SOTA) (Dopazo,J. and Carazo,J.M. (1997) J. Mol. Evol., 44, 226-233), is a neural network that grows adopting the topology of a binary tree. The result of the algorithm is a hierarchical cluster obtained with the accuracy and robustness of a neural network.