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We present a combination of experimental STM images and DFT calculations to understand the atomic scale contrast of features found in high-resolution STM images. Simulating different plausible structural models for the tip, we have been able to reproduce various characteristics previously reported in experimental images on TiO(2)(110)-(1 x 1) under controlled UHV conditions. Our results allow us to determine the influence of different chemical and morphological tip terminations on the atomic-resolution STM images of the TiO(2)(110)-(1 x 1) surface. The commonest images have been properly explained using standard models for a W tip, either clean or with a single O atom located at the apex. Furthermore, a double transfer of oxygen atoms can account for different types of bizarre atomic-resolution features occasionally seen, and not conclusively interpreted before. Importantly, we discuss how typical point-defects are imaged on this surface by different tips, namely bridging O vacancies and adsorbed OH groups.

Commonly, simple mathematical models can not be used to describe exactly the biological processes due to their higher complexity. In fact, most biological interactions cannot be elucidated by a simple stepwise algorithm or a precise formula, particularly when the data are complex or noisy. ANNs allows an accurate description of those kind of biological processes in plant science, offering new advantages over traditional treatments as the possibility of a model, prediction and optimize results. Different kind of data can be analyzed using a unique and "easy to use" technology. Researchers with a high specialized mathematical background are not required and ANNs offer the possibility of achieving the whole view of the experimental study with a limited number of experiments and costs. Additionally, it is possible to add new inputs and outputs to the database to reach a new understanding.

We have studied the first stages leading to the formation of self-assembled monolayers of S-cysteine molecules adsorbed on a Au(111) surface. Density functional theory (DFT) calculations for the adsorption of individual cysteine molecules on Au(111) at room temperature show low-energy barriers all over the 2D Au(111) unit cell. As a consequence, cysteine molecules diffuse freely on the Au(111) surface and they can be regarded as a 2D molecular gas. The balance between molecule-molecule and molecule-substrate interactions induces molecular condensation and evaporation from the morphological surface structures (steps, reconstruction edges, etc.) as revealed by scanning tunnelling microscopy (STM) images. These processes lead progressively to the formation of a number of stable arrangements, not previously reported, such as single-molecular rows, trimers, and 2D islands. The condensation of these structures is driven by the aggregation of new molecules, stabilized by the formation of electrostatic interactions between adjacent NH(3)(+) and COO(-) groups, together with adsorption at a slightly more favorable quasi-top site of the herringbone Au reconstruction.

In this work, we compared the unique artificial neural networks (ANNs) technology with the usual statistical analysis to establish its utility as an alternative methodology in plant research. For this purpose, we selected a simple in vitro proliferation experiment with the aim of evaluating the effects of light intensity and sucrose concentration on the success of the explant proliferation and finally, of optimizing the process taking into account any influencing factors. After data analysis, the traditional statistical procedure and ANNs technology both indicated that low light treatments and high sucrose concentrations are required for the highest kiwifruit microshoot proliferation under experimental conditions. However, this particular ANNs software is able to model and optimize the process to estimate the best conditions and does not need an extremely specialized background. The potential of the ANNs approach for analyzing plant biology processes, in this case, plant tissue culture data, is discussed.

We have established the conditions for which nanohole and nanodot patterns are produced on Si(001) surfaces by 1 keV Ar(+) ion beam sputtering (IBS) at normal incidence with an alternating cold cathode ion source (ACC-IS). Nanohole patterns are produced within a narrow IBS window for low ion fluxes (<100 µA cm(-2)) and relatively low ion fluences (<10(18) ions cm(-2)) whereas nanodot morphologies are produced above this window. The nanohole pattern is not stable after prolonged irradiation since it evolves to a nanodot morphology. Rutherford backscattering spectrometry (RBS) measurements show that nanohole patterns are produced when the metal content on the irradiated surfaces is higher (within (2.5-3.5 × 10(15)) atoms cm(-2)) than in the case of nanodots (<2.5 × 10(15) atoms cm(-2)). The different metal content is related to the ACC-IS operation, since the set-up provides simultaneous incorporation of Fe and Mo on the target surface from the erosion of the cathodes and sample holder, respectively. The role of metal incorporation on pattern selectivity has been corroborated qualitatively by extending the results obtained with the ACC-IS to a standard Kaufman-type source. In order to gain further information on the metal effects, chemical analysis of the surface has been performed to complement the compositional RBS results, showing for the first time the relevant participation of metal silicides. Further outlook and a discussion regarding the role of metal incorporation are also given.

We present a DNA biosensor based on self-assembled monolayers (SAMs) of thiol-derivatized peptide nucleic acid (PNA) molecules adsorbed on gold surfaces. Previous works have shown that PNA molecules at an optimal concentration can be self-assembled with their molecular axes normal to the surface. In such structural configuration BioSAMs of PNAs maintain their capability for recognizing complementary DNA. We describe the combined use of PM-RAIRS and synchrotron radiation XPS for the detection and spectroscopic characterization of PNA-DNA hybridization process on gold surfaces. RAIRS and XPS are powerful techniques for surface characterization and molecular detection, which do not require a fluorescence labeling of the target. We present a characterization of the spectroscopic IR and XPS features, some of them associated to the phosphate groups of the DNA backbone, as an unambiguous signature of the PNA-DNA heteroduplex formation. The N(1s) XPS core level peak after DNA hybridization is decomposed in curves components, and every component assigned to different chemical species. Therefore, the results obtained by means of two complementary structural characterization techniques encourage the use of PNA-based biosensors for the detection of DNA molecules on natural samples.

Combining STM, LEED, and density functional theory, we determine the atomic surface structure of rutile TiO2 (110)-(1 x 2): nonstoichiometric Ti2O3 stripes along the [001] direction. LEED patterns are sharp and free of streaks, while STM images show monatomic steps, wide terraces, and no cross-links. At room temperature, atoms in the Ti2O3 group have large amplitudes of vibration. The long quasi-1D chains display metallic character, show no interaction between them, and cannot couple to bulk or surface states in the gap region, forming good atomic wires.

Encouraged by the positive relationship between joint laxity and panic anxiety, our objective in this study was to compare widespread cultural fears in subjects with and without joint hypermobility syndrome and to assess whether this relationship is sustained for common fears as well. A sample consisting of 1,305 subjects from a rural town were assessed for joint hypermobility syndrome using Beighton's criteria. We assessed fear intensity and frequency using a modified version of the Fear Survey Schedule (FSS-III). Intense fears, defined with a score of 3-4, were compared between hypermobile and nonhypermobile subjects. The analysis was carried out separately for men and women. Nonparametric analysis was applied throughout. Joint hypermobility syndrome was found in 19.9% (141) of women and 6.9% (41) of men. Concerning the fear survey, when we compared the groups with and without joint hypermobility, the mean total scores for both genders were significantly higher for the hypermobile group. When we analyzed each item individually, 43 out of the 44 most severe fears in women and 36 out of the 39 in men, scores were significantly higher in the hypermobile group. We found significant differences between subjects with and without joint hypermobility when assessing specific fears, reinforcing the hypothesis that intensity of fears is greater in subjects with joint hypermobility syndrome. These results show that the association of joint laxity and phobic anxiety is sustained for intense fears and might represent a susceptibility factor for these anxiety conditions.

Hydrographic data collected during the cruise HIDROPRESTIGE were combined with meteorological and dynamic data provided by remote sensors and drifting/moored buoys, to describe the surface circulation of the Northern Iberian basin in March-April 2003. Sea surface winds transported the floating Prestige oil slicks from the sinking area to the continental slope off the Rías Baixas in 1/2 month: the surface current intensity was 2% of the wind intensity and it was rotated clockwise 5 degrees from the wind direction. Mesoscale cyclonic and anticyclonic structures west of 10 degrees W increased the residence time of oil patches in the Northern Iberian basin, as compared with the expected southwards flow of the Iberian current (IC). On the other hand, the Iberian poleward current (IPC) formed a marked surface front with coastal waters, preventing the entry of fuel oil into the rías. PAHs in the surface layer during the cruise were <0.5 microgL(-1), except in the Galicia bank (approximately 1 microg L(-1); where the Prestige tanker was still leaking) and the vicinity of Cape Fisterra (approximately 1.5 microg L(-1); where the convergence front between the IPC and coastal waters vanished).

We have characterized self-assembled monolayers (SAMs) of thiol-derivatized peptide nucleic acid (PNA) chains adsorbed on gold surfaces by using reflection absorption infrared spectroscopy (RAIRS) and X-ray photoemission spectroscopy (XPS) techniques. We have found that the molecular orientation of PNAs strongly depends on surface coverage. At low coverage, PNA chains lie flat on the surface, while at high coverage, PNA molecules realign their molecular axes with the surface normal and form SAMs without the need of co-immobilization of spacers or other adjuvant molecules. The change in the molecular orientation has been studied by infrared spectroscopy and it has been confirmed by atomic force microscopy (AFM). PNA immobilization has been followed by analyzing the N(1s) XPS core-level peak. We show that the fine line shape of the N(1s) core-level peak at optimal concentration for biosensing is due to a chemical shift. A combination of the above-mentioned techniques allow us to affirm that the structure of the SAMs is stabilized by molecule-molecule interactions through noncomplementary adjacent nucleic bases.

Rheumatoid arthritis (RA) is a systemic disorder that primary involves joints, although renal disease has also been associated it is not common that rapidly progressive glomerulonephritis (RPGN) appears. We report the case of a patient with nodular and aggressive RA who had an acut renal failure secondary to ANCA positive RPGN due to a Microscopic polyangiitis who was not responsive to steroids and cyclophosphamide therapy.

We report on the formation of ordered self-assembled monolayers (SAMs) of single-stranded peptide nucleic acids (ssPNA). In spite of their remarkable length (7 nm) thiolated PNAs assemble standing up on gold surfaces similarly to the SAMs of short alkanethiols. SAMs of ssPNA recognize complementary nucleic acids, acting as specific biosensors that discriminate even a point mutation in target ssDNA. These results are obtained by surface characterization techniques that avoid labeling of the target molecule: x-ray photoemission, x-ray absorption and atomic force microscopy.

A screening of 416 microorganisms from different taxonomical groups (bacteria, actinomycetes, yeasts, and filamentous fungi) has been performed looking for active strains in the stereoselective oxidation of secondary alcohols. The working collection was composed of 71 bacterial strains, 45 actinomycetes, 59 yeasts, 60 basidiomycetes, 33 marine fungi, and 148 filamentous fungi. All microorganisms selected were mesophilic. Yeasts were the most active microbial group in the whole-cell-catalyzed oxidation. Williopsis californica, Williopsis saturnus, and Pachysolen tannophilus were the strains of greatest interest, both as growing cells and as resting cells. The oxidation of the alcohols takes place when cells are in the stationary growth phase (after 48 h of culture). These three strains are S-stereoselective for the oxidation of racemic secondary alkanols and show stereospecificity in the oxidation of menthol or neo-menthol, whereas iso-menthol is not oxidized. In the case of the 1-tetrahydronaphtol enantiomers, only the S-enantiomer is oxidized. The three strains were immobilized by entrapment using agarose and agar from algae of the Gracilaria genus. The agarose derivatives displayed significant improvement in the stereospecificity of the reactions.

This study examines the association between joint hypermobility syndrome and anxiety in a nonclinical sample. Subjects (N = 526) receiving a medical check-up were assessed with the Hospital del Mar hypermobility criteria and the State-Trait Anxiety Inventory. Scores for trait anxiety, and to a lesser extent state anxiety, were significantly higher among subjects with joint hypermobility syndrome than among subjects without this syndrome (median trait anxiety scores for women: 17 versus 11; median scores for men: 13 versus 1). These findings indicate that the association of joint hypermobility syndrome and anxiety holds even for subjects with no psychiatric diagnosis. Therefore, it seems that this benign connective tissue disorder is a predisposing factor for trait anxiety. However, it is necessary to further explore and define the biological basis of this syndrome, as well as its associations and clinical expressions, which interact with great complexity.

Background: Optimal immunosuppression is essential to maintain kidney allograft viability but minimizing toxicity is also fundamental., Objective: This article compares immunosuppressants, corticosteroids, cyclosporine, tacrolimus, and basiliximab, which are used in the treatment regimens for renal transplantation. The analyses evaluated their effectiveness to prevent acute rejection episodes and to reduce the appearance of other complications, mainly infectious disease complications., Methods: Ninety-five patients were analysed during the first year after primary renal transplantation. These patients were included in a random way in 3 different groups according to the immunosuppressant drug therapy: Group I (35 patients) received corticosteroids + CsA; Group II (35 patients) received corticosteroids + CsA + Basiliximab; Group III (25 patients) received corticosteroids + Tacrolimus + Basiliximab., Results: Among the 95 patients, 9 presented with an acute rejection episode in Group I. None in Group II, and one in group III. With reference to the infectious disease complications, the incidence of oral herpes was one case in Group I, 4 cases in Group II, and 2 cases in group III., Conclusions: Treatment with Basiliximab produced a significantly lower incidence of acute rejection cases and an increase in infectious disease complications, such as lip herpes.

Combining electrochemical methods, in situ scanning tunneling microscopy, and surface x-ray diffraction allowed study of the structure and kinetics of S/Au(111) electrodes in aqueous electrolytes under potential control. Integrated intensities of a particular crystal truncation rod at anti-Bragg conditions were used to trace the sulfur adsorption and desorption as a function of electrode potential in real time. The S desorption is a first order process and the adsorption follows a Langmuir isotherm. A weakly bound S layer is found on the surface before charge transfer, and then specific adsorption occurs.

Objectives: Acquired hemophilia is a rare disease caused by the development of autoantibodies against factor VIII. Since 1981 we have observed 17 patients with this disorder in our institution. The objective of this survey was to assess the epidemiological features, clinical course, and mortality rate of these patients, with special emphasis on therapy-related side-effects. Also, we present our results with an immunosuppressive approach based on the severity of bleeding episodes., Methods: Clinical records of all patients with acquired hemophilia due to factor VIII inhibitor admitted or referred to our hospital between 1981 and 2001 were reviewed retrospectively. We collected each patient's sex, age, medical history, presenting symptoms, activated partial thromboplastin time, factor VIII activity, and inhibitor titre. Patient's clinical courses, including their bleeding episodes, response to therapy, and therapy-related side-effects, were also recorded., Results: Complete and partial responses were achieved in 14 and one patient, respectively (overall response rate 88%) after a median time to complete response of 3.5 months (range 30 d - 25 months). The inhibitor-related and overall mortality rates were 12% and 29%, respectively. Side-effects were frequent: two patients had blood-borne infections, three patients had thrombotic complications, and nine patients had immunosuppressive therapy-related side-effects. In five patients, discontinuation of cyclophosphamide or prednisone was required., Conclusions: Although our response rates were remarkable, this survey showed that treatment-related morbidity could also be very important. Therefore, it is pertinent to bear in mind these potential side-effects in order to decide the most appropriate therapy for each particular patient.

Anxiety disorders are complex and common psychiatric illnesses associated with considerable morbidity and social cost. We have studied the molecular basis of the cooccurrence of panic and phobic disorders with joint laxity. We have identified an interstitial duplication of human chromosome 15q24-26 (named DUP25), which is significantly associated with panic/agoraphobia/social phobia/joint laxity in families, and with panic disorder in nonfamilial cases. Mosaicism, different forms of DUP25 within the same family, and absence of segregation of 15q24-26 markers with DUP25 and the psychiatric phenotypes suggest a non-Mendelian mechanism of disease-causing mutation. We propose that DUP25, which is present in 7% control subjects, is a susceptibility factor for a clinical phenotype that includes panic and phobic disorders and joint laxity.

Objective: The purpose of this study was to assess whether joint hypermobility syndrome is more frequent in patients with panic disorder, agoraphobia, or both than in control subjects and, if so, to determine whether mitral valve prolapse modifies or accounts in part for the association., Method: A case-control study was conducted in a general teaching hospital outpatient clinic. Subjects were 99 patients, newly diagnosed and untreated, with panic disorder, agoraphobia, or both and two groups of age- and sex-matched control subjects: 99 psychiatric patients and 64 medical patients who had never suffered from any anxiety disorder. Measures consisted of the Structured Clinical Interview for DSM-III-R, Beighton's criteria for joint hypermobility syndrome, and two-dimensional and M-mode echocardiogram. The presence of mitral valve prolapse and joint hypermobility syndrome was explored by raters who were blind to subjects' psychiatric status., Results: Joint hypermobility syndrome was found in 67.7% of patients with anxiety disorder but in only 10.1% of psychiatric and 12.5% of medical control subjects. On the basis of statistical analysis, patients with anxiety disorder were over 16 times more likely than control subjects to have joint laxity. These findings were not altered after the presence of mitral valve prolapse was taken into account. Of the patients with anxiety disorder, those who had joint hypermobility syndrome were younger and more often women and had an earlier onset of the disorder than those without joint hypermobility syndrome., Conclusions: Joint laxity is highly prevalent in patients with panic disorder, agoraphobia, or both and may reflect a constitutional disposition to suffer from anxiety. Mitral valve prolapse plays a secondary role in the association between joint hypermobility and anxiety.

Histoplasmosis is a fungal disease caused by the dimorphous fungus Histoplasma capsulatum (Hc). Cyclophosphamide (Cy) was used as an immunomodulator capable of modifying the course of the disease, as well as of regulating the mechanisms involved in T-lymphocyte mediated immune response. Rats were subjected to intracardiac inoculation of Hc followed by a fractionated treatment with a 100 mg/kg body weight dose of Cy on days +4, +5, +6, +7 and +11 pi. Until day 26 pi, treatment with Cy caused 85% mortality whereas no mortality was observed among animals only inoculated with Hc. On day 14 pi, the group of Hc animals showed a delayed hypersensitivity test (DH) of 26.60 + 13.96 as determined by the swelling of the leg. Conversely, DH was significantly depressed in rats inoculated with Hc and treated with Cy: 3.88 +/- 1.00 (p < 0.01). Colony forming units count in this group was 2020 CFU/g of spleen, and 24 CFU/g of spleen (p < 0.01) in controls. A macroscopic study of the organs revealed that the animals in the Hc+Cy group had spleenomegaly and lungs with granuloma and hemorrhagic spots. The controls only presented small lung abscesses. These findings lead to the conclusion that Cy causes a deterioration of cell mediated immune response which results in the manifestation of an acute, fatal experimental mycosis.

The development of consultation-liaison psychiatry in Portuguese general hospitals raises the need for specific training to be included in the preparation of psychiatric trainees. In order to contribute to a better quality of liaison psychiatric training we propose guidelines for this training period. We describe the aims of a training period, the core curriculum, the structure of this training and provide a bibliography. We also propose a systematic evaluation profile for psychiatric trainees and supervisor.

The aim of the study was to test whether an association exists between asthenic somatotype, as measured by the Quetelet index, and panic and or agoraphobia. Ninety-nine cases with panic and/or agoraphobia diagnosed at the psychiatric outpatient clinic of a general teaching hospital were compared to 99 controls with psychiatric conditions other than panic and agoraphobia, and to 64 medical controls, matched by age and gender. No differences in weight, height and raw Quetelet and ponderal indexes were found between panic cases and controls. However, 33.3% of cases, but only 19.2% of psychiatric controls and 18.7% of medical controls, were in the asthenic group as defined by the lower quartile of the Quetelet index (age and sex adjusted odds ratio = 2.33, 95% C.I.: 1.21-4.11). In the entire sample, the asthenic somatotype was associated with lower age and with the presence of hypermobility of joints. Since both panic disorder and mitral valve prolapse may be associated with the joint hypermobility syndrome (JHS), an inherited disorder of collagen synthesis, it is suggested that the relationship found between panic and asthenic somatotype might be mediated through JHS.

Resection of the radial head and partial open synovectomy of the elbow have been used in the treatment of repeated haemarthroses of the elbows in 15 patients with haemophilia. The indications for the index operation were: severe pain and bleeding in the elbow that occurred in spite of appropriate, episodic, replacement therapy over a period of more than 6 months, associated with hypertrophy of the radial head and a significant loss of pronation-supination. The long-term results were assessed retrospectively according to the classification recommended by the Orthopaedic Advisory Committee of the World Federation of Hemophilia. In the operated group, three patients had a good result, seven were fair, and five poor. It is concluded that this procedure appears to reduce the incidence of haemarthrosis but did not slow the rate of evolution of radiographic changes.

Rope-pumps are now widely promoted as a low cost, easily maintained means to improve water availability in developing countries. However, in some instances their acceptance has been limited by concerns over the microbiological quality of the water. This study looked at the well water quality under a variety of conditions, comparing unimproved bucket and rope wells with wells with a windlass and rope-pump wells with and without a concrete cover. Other factors influencing the water quality were also examined. Results indicate a 62% reduction of the geometric mean of the faecal coliform contamination of the well water as a result of the installation of a rope-pump with or without a concrete cover. Other factors found to influence the level of contamination of water in hand-dug wells were rainfall, number of households using the well, amount of water extracted daily and the distance of the well from the nearest kitchen. The last three factors probably reflect domestic activities with poor hygiene around the well. The installation of a simple rope-pump on family wells improves the water quality and availability at a favourable cost/benefit ratio.

The goal of this work was to develop in solid medium a fast method to obtain Paracoccidioides brasiliensis (Pb) with a high yield. Four culture media were assayed: Sabouraud honey-agar, Sabouraud dextrose-agar, tomato -agar-medium (TOM) and a medium based on grape pulp. The most exhuberant growth was observed in medium based on grape pulp. Antigen was prepared in microscale at 6, 10 and 15 days incubation of solid cultures and the crude product concentrated by means of Centriplus tubes (Helena, France). Isolated antigens were subjected to polyacrylamide gel electrophoresis, followed by immunolabelling and detection of the characteristic gp45 antigen employing human and Pb-infected rat sera. Best results were observed after 10 days culture in grape medium. None of the other three media afforded comparable results.

We have studied the knees of 50 patients with hemophilia A, using ultrasound (US) when conventional radiology did not detect any secondary osseous changes. The sonographic images were compared with those obtained from 50 healthy controls. The mean age of this series was 14.6 years. Our results suggest that sonography as a diagnostic technique in the initial stages of hemophilia permits differentiation between suprapatellar effusion and synovial thickening. It also reveals early cartilaginous involvement.

Etretinate is an aromatic retinoid extensively used on Dermatology. Its toxic effects, however, reduce its application from a clinical point of view. In the present paper, we study etretinate intoxication of 48 growing Wistar rats. The intoxication was for 12 weeks using etretinate doses of 0.5 and 6 (mg/kg)/day. The concentrations of etretinate in plasma and liver were determined. Total seric cholesterol and triglyceride concentrations were analyzed. Structural and ultrastructural histological studies of liver samples were carried out. Continuous etretinate ingestions seem to produce an alteration in the detoxication of enzymatic complexes in the growing rats with both the concentrations, due to the increase in etretinate blood plasma observed during the study. There is a relationship between the etretinate dose and its blood plasma concentration and toxic effect, but there is not with etretinate concentration in the liver. The blood plasma concentration of cholesterol and triglycerides is not related to histological liver lesions. The histological study confirms hepatotoxicity with both doses. Nevertheless, the anatomopathological lesions observed do not seem to be related to the blood plasma and liver etretinate concentrations.