Cone contrast influence on components of the pattern onset/offset VECP

Transient visual evoked cortical potentials (VECP) were recorded from the scalp of healthy normal trichromats (n = 12). VECPs were elicited by onset/offset presentation of patterned stimuli of two kinds: isochromatic luminance-modulated, and equiluminant red-green modulated, sine wave gratings. The amplitude and latency of the major onset components of the onset/offset VECP were measured and plotted as a function of the logarithm of pooled cone contrast. The early onset components, achromatic C1 and chromatic N1, increase linearly with log contrast, but N1 has a higher contrast gain than C1. The late onset components, achromatic C2 and chromatic N2, have similar contrast gain, and similar response as a function of contrast level: both increase in the low-to-medium range of contrasts and saturate at high contrast levels. In the range of pooled cone contrast tested, C1 and N1 show similar latencies, whilst C2 shows shorter latencies than N2. We suggest that C1 and N1 are generated by the same visual mechanism with high red-green contrast gain and low luminance contrast gain, whilst C2 and N2 are generated by different visual mechanisms.

Twelve chromatically opponent ganglion cell types in turtle retina

The turtle retina has been extensively used for the study of chromatic processing mechanisms. Color opponency has been previously investigated with trichromatic paradigms, but behavioral studies show that the turtle has ail ultraviolet (UV) channel and a tetrachromatic visual system. Our laboratory has been working ill the characterization of neuronal responses in the retina of vertebrates using stimuli in the UV-visible range of the electromagnetic spectrum. In the present investigation, we recorded color-opponent responses from turtle amacrine and ganglion cells to UV and visible stimuli and extended our previous results that UV color-opponency is present at the level of the inner nuclear layer. We recorded from 181 neurons, 36 of which were spectrally opponent. Among these, there were 10 amacrine (5%), and 26 ganglion cells (15%). Morphological identification of color-opponent neurons was possible for two ganglion cell classes (G17 and G22) and two amacrine cell classes (A22 and A23b). There was a variety of cell response types and a potential for complex processing of chromatic stimuli, with intensity- and wavelength-dependent response components. Ten types of color opponency were found in ganglion cells and by adding previous results from our laboratory, 12 types of opponent responses have been found. The majority of the ganglion cells were R+UVBG- and RG+UVB-color-opponents but there were other less frequent types of chromatic opponency. This study confirms the participation of a UV channel in the processing of color opponency in the turtle inner retina and shows that the turtle visual system has the retinal mechanisms to allow many possible chromatic combinations.

Mercury toxicity in Amazon gold miners: Visual dysfunction assessed by retinal and cortical electrophysiology

Amazonian gold mining activity results in human exposure to mercury vapor. We evaluated the visual system of two Amazonian gold miners (29 and 37 years old) by recording the transient pattern electroretinogram (tPERG) and transient pattern visual evoked potential (tPVEP). We compared these results with those obtained from a regional group of control subjects. For both tPERG and tPVEP, checkerboards with 0.5 or 2 cycles per degree (cpd) of spatial frequency were presented in a 16 degrees squared area, 100% Michelson contrast, 50cd/m(2) mean luminance, and 1 Hz square-wave pattern-reversal presentation. Two averaged waveforms (n = 240 sweeps, Is each) were monocularly obtained for each subject in each condition. Both eyes were monocularly tested only in gold miners. Normative data were calculated using a final pooled waveforin with 480 sweeps. The first gold miner, LCS, had normal tPERG responses. The second one, RNP, showed low tPERG (P50 component) amplitudes at 0.5cpd for both eyes, outside the normative data, and absence of response at 2 cpd for his right eye. Delayed tPVEP responses (P 100 component) were found at 2 cpd for LCS but the implicit times were inside the normative data. Subject RNP also showed delayed tPVEP responses (all components), but only the implicit time obtained with his right eye was outside the normative data at 2cpd. We conclude that mercury exposure levels found in the Amazon gold miners is high enough to damage the visual system and can be assessed by non-invasive electrophysiological techniques. (C) 2007 Elsevier Inc. All rights reserved.

Nuclear-modification factor for open-heavy-flavor production at forward rapidity in Cu plus Cu collisions at root s(NN)=200 GeV

Background: Heavy-flavor production in p + p collisions is a good test of perturbative-quantum-chromodynamics (pQCD) calculations. Modification of heavy-flavor production in heavy-ion collisions relative to binary-collision scaling from p + p results, quantified with the nuclear-modification factor (R-AA), provides information on both cold-and hot-nuclear-matter effects. Midrapidity heavy-flavor R-AA measurements at the Relativistic Heavy Ion Collider have challenged parton-energy-loss models and resulted in upper limits on the viscosity-entropy ratio that are near the quantum lower bound. Such measurements have not been made in the forward-rapidity region. Purpose: Determine transverse-momentum (p(T)) spectra and the corresponding R-AA for muons from heavy-flavor meson decay in p + p and Cu + Cu collisions at root s(NN) = 200 GeV and y = 1.65. Method: Results are obtained using the semileptonic decay of heavy-flavor mesons into negative muons. The PHENIX muon-arm spectrometers measure the p(T) spectra of inclusive muon candidates. Backgrounds, primarily due to light hadrons, are determined with a Monte Carlo calculation using a set of input hadron distributions tuned to match measured-hadron distributions in the same detector and statistically subtracted. Results: The charm-production cross section in p + p collisions at root s = 200 GeV, integrated over p(T) and in the rapidity range 1.4 < y < 1.9, is found to be d(sigma e (e) over bar)/dy = 0.139 +/- 0.029 (stat)(-0.058)(+0.051) (syst) mb. This result is consistent with a perturbative fixed-order-plus-next-to-leading-log calculation within scale uncertainties and is also consistent with expectations based on the corresponding midrapidity charm-production cross section measured by PHENIX. The R-AA for heavy-flavor muons in Cu + Cu collisions is measured in three centrality bins for 1 < p(T) < 4 GeV/c. Suppression relative to binary-collision scaling (R-AA < 1) increases with centrality. Conclusions: Within experimental and theoretical uncertainties, the measured charm yield in p + p collisions is consistent with state-of-the-art pQCD calculations. Suppression in central Cu + Cu collisions suggests the presence of significant cold-nuclear-matter effects and final-state energy loss.

Effectiveness of Piezoelectric Surgery in Preparing the Lateral Window for Maxillary Sinus Augmentation in Patients with Sinus Anatomical Variations: A Case Series

Purpose: The present article sought to evaluate the effectiveness of a piezoelectric surgical unit for maxillary sinus augmentation surgeries in avoiding perforation of the sinus membrane and other possible procedural complications in patients with anatomical variations of the sinus. Materials and Methods: Twenty-five patients presenting sinus anatomical variations, who were indicated for a total of 40 sinus grafting procedures performed by the lateral window approach with a piezoelectric device, were analyzed. After 6 months of healing, implants were placed. Information collected included clinical and computed tomographic information on anatomical variations in the sinus bone walls, in the size of the sinus, and in the thickness of the sinus membrane. Occurrence of sinus membrane perforation and computed tomographic measurements of the amount of bone height gained with the grafting procedures were also recorded. Results: Only two patients presented a small perforation (less than 5 mm in diameter) of the sinus membrane, which occurred only after osteotomies of the lateral windows and did not compromise the surgical outcome. No implants were lost during a mean follow-up period of 19 months. Conclusion: The use of piezoelectric surgery allowed for the accomplishment of all rehabilitation treatments within the follow-up period of this study. INT J ORAL MAXILLOFAC IMPLANTS 2012;27:1211-1215

Single Center Experience With Elective Surgical Patients as Living Kidney Donors

Purpose. To report a single center experience with elective surgical patients as living kidney donors. Methods. We retrospectively analyzed a prospective database of 458 living kidney donors from September 2005 to May 2011. Fifteen (3.2%) of them were elective surgical patients simultaneously undergoing living donor nephrectomy. We reviewed age, gender, operative time, intraoperative blood transfusion, intra- and postoperative complications, as well as length of hospital stay. Recipients were evaluated for delayed graft function. Four hundred forty-three patients undergoing living donor nephrectomy alone composed the control group. Results. Among the elective surgical patients group, the mean (range) operative time was 155 (90 to 310) minutes and mean (range) length of hospital stay was 3 (2 to 9) days. One (6.7%) recipient displayed delayed graft function. Among the regular living kidney donors group, the mean (range) operative time was 100 (70 to 150) minutes, mean (range) length of hospital stay was 3 (2 to 5) days, and delayed graft function was observed in 5.6% of recipients. Only operative time (P = .03) was significantly different between the groups. Conclusions. Elective surgical patients are potential donors who may be treated at the same time as the living donor nephrectomy.

Three-Dimensional Ultrasonographic Assessment of Fetal Total Lung Volume as a Prognostic Factor in Primary Pleural Effusion

Objectives-The purpose of this study was to predict perinatal outcomes using fetal total lung volumes assessed by 3-dimensional ultrasonography (3DUS) in primary pleural effusion. Methods-Between July 2005 and July 2010, total lung volumes were prospectively estimated in fetuses with primary pleural effusion by 3DUS using virtual organ computer-aided analysis software. The first and last US examinations were considered in the analysis. The observed/expected total lung volumes were calculated. Main outcomes were perinatal death (up to 28 days of life) and respiratory morbidity (orotracheal intubation with mechanical respiratory support >48 hours). Results-Twelve of 19 fetuses (63.2%) survived. Among the survivors, 7 (58.3%) had severe respiratory morbidity. The observed/expected total lung volume at the last US examination before birth was significantly associated with perinatal death (P < .01) and respiratory morbidity (P < .01) as well as fetal hydrops (P < .01) and bilateral effusion (P = .01). Conclusions-Fetal total lung volumes may be useful for the prediction of perinatal outcomes in primary pleural effusion.

Gonadal function in male patients with ankylosing spondylitis

Objective: To assess reproductive function in male ankylosing spondylitis (AS) patients in comparison to healthy controls. Methods: Twenty AS patients were compared to 24 healthy male subjects with regard to demographic data, urological examination, testicular ultrasound (US), semen analysis, anti-sperm antibodies, and hormone profile. Exclusion criteria were present use of sulfasalazine or methotrexate, and ever use of biological/cytotoxic agents. Disease activity of AS was evaluated by clinical and laboratory assessments. Results: Demographic data were similar in AS and controls (p = 0.175). Varicocele was found significantly more frequently in AS patients than in controls (40% vs. 8%, p = 0.027). Semen analysis revealed no significant differences in sperm quality between AS patients and controls (p > 0.05). By contrast, the median of normal sperm forms was significantly lower in AS patients with vs. those without varicocele [13.5 (range 2-27) vs. 22 (range 10-32.5)%, p = 0.049] whereas no difference in sperm morphology was observed comparing AS patients and controls without varicocele (p = 0.670). Comparison of AS patients with and without varicocele showed that anti-sperm antibodies, hormones, inflammatory markers, and disease activity scores did not contribute to the impaired sperm morphology observed in AS patients with varicocele. Conclusions: An increased frequency of varicocele was found in AS patients associated with sperm abnormalities but independent of therapy, anti-sperm antibodies, hormonal alterations, or disease parameters. Investigation for varicocele should be routine in AS patients with fertility problems.

Expression of PAFR as Part of a Prosurvival Response to Chemotherapy: A Novel Target for Combination Therapy in Melanoma

Melanoma cells express the platelet-activating factor receptor (PAFR) and, thus, respond to PAF, a bioactive lipid produced by both tumour cells and those in the tumour microenvironment such as macrophages. Here, we show that treatment of a human melanoma SKmel37 cell line with cisplatin led to increased expression of PAFR and its accumulation. In the presence of exogenous PAF, melanoma cells were significantly more resistant to cisplatin-induced cell death. Inhibition of PAFR-dependent signalling pathways by a PAFR antagonist (WEB2086) showed chemosensitisation of melanoma cells in vitro. Nude mice were inoculated with SKmel37 cells and treated with cisplatin and WEB2086. Animals treated with both agents showed significantly decreased tumour growth compared to the control group and groups treated with only one agent. PAFR accumulation and signalling are part of a prosurvival program of melanoma cells, therefore constituting a promising target for combination therapy for melanomas.

Primary antiphospholipid syndrome: morphofunctional penile abnormalities with normal sperm analysis

Objective: To perform a global gonadal and sexual functions assessment in primary antiphospholipid syndrome (PAPS) patients. Methods: A cross-sectional study was conducted in 12 male PAPS patients and 20 healthy controls. They were assessed by demographic data, clinical features, systematic urological examination, sexual function, testicular ultrasound, seminal parameters according to the World Health Organization (WHO), seminal sperm antibodies, and hormone profile, including follicle stimulating hormone (FSH), luteinizing hormone (LH), morning total testosterone, and thyroid hormones. Results: The median of current age and age of spermarche were similar in PAPS patients and controls (37.5 vs. 32.4 years, p = 0.270, and 13.1 vs. 12.85 years, p = 0.224, respectively), with a higher frequency of erectile dysfunction in the former group (25% vs. 0%, p = 0.044). Further analysis of PAPS patients with and without previous arterial thrombosis demonstrated that the median penis circumference was significantly lower in PAPS with arterial thrombosis than in PAPS without this complication (8.1 [6-10] vs. 10.2 [10-11] cm, p = 0.007). In addition, the median penis circumference was significantly lower in PAPS patients with erectile dysfunction than in patients without this complication (7.5 [6-9.5] vs. 9.5 [7.5-11] cm, p = 0.039). Regarding seminal analysis, the median sperm concentration, sperm motility, and normal sperm forms by WHO guidelines were comparable in PAPS patients and controls (141.5 [33-575] vs. 120.06 [34.5-329] x 106/ml, p = 0.65; 61.29 [25-80] vs. 65.42 [43-82]%, p = 0.4; 21.12 [10-42.5] vs. 23.95 [10-45]%, p = 0.45, respectively), and none of them had oligo/azoospermia. No differences were observed between PAPS patients and controls regarding the frequency of antisperm antibodies, testicular volume by ultrasound, or hormone profile (FSH, LH, morning total testosterone, and thyroid hormone) (p > 0.05). Conclusions: Normal testicular function has been identified in PAPS patients, in spite of morphofunctional penile abnormalities. Previous arterial thrombosis may underlie penile anthropometry alteration. Lupus (2012) 21, 251-256.

Cone Beam Computed Tomographic Evaluation of a Maxillary Alveolar Ridge Reconstruction With Iliac Crest Graft and Implants

The present article discusses an atrophic maxilla reconstruction with iliac crest bone block and particulate grafts and dental implants. Onlay block grafts were used to restore bone volume of the anterior maxilla, whereas bilateral sinus floor augmentation was performed using a particulate graft. Ten months after the grafting surgery, 9 dental implants were placed to rehabilitate the case. Results of a 7-year follow-up were obtained clinically and by cone beam computed tomographic images.

Evolution of pi(0) Suppression in Au plus Au Collisions from root s(NN)=39 to 200 GeV

Neutral-pion pi(0) spectra were measured at midrapidity (vertical bar y vertical bar < 0.35) in Au + Au collisions at root s(NN) = 39 and 62.4 GeV and compared with earlier measurements at 200 GeV in a transverse-momentum range of 1 < p(T) < 10 GeV/c. The high-p(T) tail is well described by a power law in all cases, and the powers decrease significantly with decreasing center-of-mass energy. The change of powers is very similar to that observed in the corresponding spectra for p + p collisions. The nuclear modification factors (RAA) show significant suppression, with a distinct energy, centrality, and p(T) dependence. Above p(T) = 7 GeV/c, R-AA is similar for root sNN = 62.4 and 200 GeV at all centralities. Perturbative-quantum-chromodynamics calculations that describe R-AA well at 200 GeV fail to describe the 39 GeV data, raising the possibility that, for the same p(T) region, the relative importance of initial-state effects and soft processes increases at lower energies. The p(T) range where pi(0) spectra in central Au + Au collisions have the same power as in p + p collisions is approximate to 5 and 7 GeV/c for root sNN = 200 and 62.4 GeV, respectively. For the root sNN = 39 GeV data, it is not clear whether such a region is reached, and the x(T) dependence of the x(T)-scaling power-law exponent is very different from that observed in the root sNN = 62 and 200 GeV data, providing further evidence that initial-state effects and soft processes mask the in-medium suppression of hardscattered partons to higher p(T) as the collision energy decreases.

VVV DR1: The first data release of the Milky Way bulge and southern plane from the near-infrared ESO public survey VISTA variables in the Via Lactea

Context. The ESO public survey VISTA variables in the Via Lactea (VVV) started in 2010. VVV targets 562 sq. deg in the Galactic bulge and an adjacent plane region and is expected to run for about five years. Aims. We describe the progress of the survey observations in the first observing season, the observing strategy, and quality of the data obtained. Methods. The observations are carried out on the 4-m VISTA telescope in the ZYJHK(s) filters. In addition to the multi-band imaging the variability monitoring campaign in the K-s filter has started. Data reduction is carried out using the pipeline at the Cambridge Astronomical Survey Unit. The photometric and astrometric calibration is performed via the numerous 2MASS sources observed in each pointing. Results. The first data release contains the aperture photometry and astrometric catalogues for 348 individual pointings in the ZYJHK(s) filters taken in the 2010 observing season. The typical image quality is similar to 0 ''.9-1 ''.0. The stringent photometric and image quality requirements of the survey are satisfied in 100% of the JHK(s) images in the disk area and 90% of the JHK(s) images in the bulge area. The completeness in the Z and Y images is 84% in the disk, and 40% in the bulge. The first season catalogues contain 1.28 x 10(8) stellar sources in the bulge and 1.68 x 10(8) in the disk area detected in at least one of the photometric bands. The combined, multi-band catalogues contain more than 1.63 x 10(8) stellar sources. About 10% of these are double detections because of overlapping adjacent pointings. These overlapping multiple detections are used to characterise the quality of the data. The images in the JHK(s) bands extend typically similar to 4 mag deeper than 2MASS. The magnitude limit and photometric quality depend strongly on crowding in the inner Galactic regions. The astrometry for K-s = 15-18 mag has rms similar to 35-175 mas. Conclusions. The VVV Survey data products offer a unique dataset to map the stellar populations in the Galactic bulge and the adjacent plane and provide an exciting new tool for the study of the structure, content, and star-formation history of our Galaxy, as well as for investigations of the newly discovered star clusters, star-forming regions in the disk, high proper motion stars, asteroids, planetary nebulae, and other interesting objects.

Modeling and Identification of an Open-frame Underwater Vehicle: The Yaw Motion Dynamics

A semi-autonomous unmanned underwater vehicle (UUV), named LAURS, is being developed at the Laboratory of Sensors and Actuators at the University of Sao Paulo. The vehicle has been designed to provide inspection and intervention capabilities in specific missions of deep water oil fields. In this work, a method of modeling and identification of yaw motion dynamic system model of an open-frame underwater vehicle is presented. Using an on-board low cost magnetic compass sensor the method is based on the utilization of an uncoupled 1-DOF (degree of freedom) dynamic system equation and the application of the integral method which is the classical least squares algorithm applied to the integral form of the dynamic system equations. Experimental trials with the actual vehicle have been performed in a test tank and diving pool. During these experiments, thrusters responsible for yaw motion are driven by sinusoidal voltage signal profiles. An assessment of the feasibility of the method reveals that estimated dynamic system models are more reliable when considering slow and small sinusoidal voltage signal profiles, i.e. with larger periods and with relatively small amplitude and offset.

Measurement of Direct Photons in Au plus Au Collisions at root s(NN)=200 GeV

We report the measurement of direct photons at midrapidity in Au + Au collisions at root s(NN) = 200 GeV. The direct photon signal was extracted for the transverse momentum range of 4 GeV/c < pT < 22 GeV/c, using a statistical method to subtract decay photons from the inclusive photon sample. The direct photon nuclear modification factor R-AA was calculated as a function of p(T) for different Au + Au collision centralities using the measured p + p direct photon spectrum and compared to theoretical predictions. R-AA was found to be consistent with unity for all centralities over the entire measured pT range. Theoretical models that account for modifications of initial direct photon production due to modified parton distribution functions in Au and the different isospin composition of the nuclei predict a modest change of R-AA from unity. They are consistent with the data. Models with compensating effects of the quark-gluon plasma on high-energy photons, such as suppression of jet-fragmentation photons and induced-photon bremsstrahlung from partons traversing the medium, are also consistent with this measurement.