Transplantation on a Posidonia oceanica meadow to facilitate its recovery after the Concordia shipwrecking.

Ecological restoration is an important tool to reverse habitat loss and recover ecosystem services. Here, for two years, we examine the dynamic of Posidonia oceanica following the restoration of a 1149 m2 meadow damaged by the Concordia shipwreck. To evaluate the suitability of a recently employed seagrass restoration protocol, we assessed the patches' survival and development by high-spatial resolution photomosaics over the whole transplanted surface. To estimate recovery trajectories, we quantified the cuttings' survival, shoot density, and Daily Leaf Production within fixed monitoring squares. The outcomes confirmed that our protocol could be efficiently applied at larger scales, showing diminutions in cuttings' survival and shoot density over the first year (up to -20%), followed by stability in the number of living cuttings and increases of leaf bundles (up to +5%/year). Our insights demonstrate that the recovery of P. oceanica can be speeded up and underline the need for case-specific transplantation strategies.

Metal removal processes in a pilot hybrid constructed wetland for the treatment of semi-synthetic stormwater.

This study investigates the reliability of a pilot hybrid constructed wetland (H-CW), located in Eastern Sicily (Italy). To address the uncertainty associated with implementing representative monitoring during highly variable storm events, unique to Mediterranean conditions, a recipe for semi-synthetic stormwater was used to evaluate the removal efficiency of the system. This was characterised by metals (Cd, Cr, Fe, Pb, Cu, Zn) and relative concentrations typically found in urban stormwater runoff (SR). Approximately one month of intensive monitoring activities were carried out and quality analyses were conducted on three matrices comprising the pilot H-CW: water, biomass (Canna indica, Typha latifolia), and volcanic gravel substrate. Metal retention in early clogging matter (SS) was also examined. The results showed a significantly high H-CW efficiency for the removal of all metals (70-98%) already at the horizontal flow unit outflow, confirming its strategic role. A metal mass balance analysis was also conducted to describe the retention capacity and influence of each system component on the overall efficiency (ranging from 87.8% for Cr to 99.2% for Pb). Metal removal was mostly related to sediment and substrate processes, while plants exhibited root bioaccumulation and phytostabilisation capacity even with a limited impact on overall system retention. The pilot H-CW exhibits characteristics suitable for the treatment of metal-enriched stormwater runoff and validates the useful application of decentralised natural systems for water resource management.

Reteporella spp. success in the re-colonization of bare coralligenous reefs impacted by Costa Concordia shipwreck: The pioneer species you did not expect.

We report here for the first time the effectiveness of Reteporella bryozoan genus in the early stage of coralligenous reefs recolonization through the analysis of the settlement and the population size structure over a two-years period at two impacted and two control sites. Results highlighted how Reteporella spp. colonies strongly recolonized, from 2017 to 2019, the bare coralligenous reefs subjected to the Costa Concordia shipwreck and its related anthropogenic disturbances, notably increasing both their density and percentage coverage. We recorded differences in colony size among impacted and control sites. Overall, large-sized colonies were reported at impacted sites exclusively, where Reteporella settlement and growth patterns differed if compared to control areas. This study highlights implications for the maintenance of the ecological functions, for the recovery processes, and for the future ecological shifts affecting one of the most important Mediterranean coastal ecosystems, the coralligenous reefs.

Impact of the Costa Concordia shipwreck on a Posidonia oceanica meadow: a multi-scale assessment from a population to a landscape level.

The Costa Concordia shipwreck permitted to assess how multiple disturbances affected marine biota at different spatial and temporal scales, evaluating the effects of mechanical and physical disturbances on Posidonia oceanica (L.) Delile, an endemic seagrass species of the Mediterranean Sea. To assess the impacts of the shipwreck and its salvaging from 2012 to 2017 at a population and a landscape level, a diversified approach was applied based on the application of a geographical information system coupled with seascape metrics and structural descriptors. Benthic habitat maps and seascape metrics highlighted cenotic transitions, as well as fragmentation and erosion phenomena, resulting in 9952 m2 of seagrass area impacted. Regression of the meadow was unveiled by both multivariate and interpolation analysis, revealing a clear spatio-temporal gradient of impacts based on distances from the wreck. Results highlighted the effectiveness of the descriptors involved that permitted to reveal temporal changes at both fine and large scales.

On the performance of a pilot hybrid constructed wetland for stormwater recovery in Mediterranean climate.

The overall efficiency of a pilot-scale hybrid constructed wetland (H-CW), located on a retail store's parking area in Eastern Sicily, for alternative treatment of stormwater runoff and of sequential batch reactor (SBR) effluent was evaluated. Experimental activities were focused on system performances, including wastewater (WW) quality and hydraulic monitoring. System design, macrophyte growth and seasonal factors influenced the pilot plant performance. Very high removal efficiency for microbial indicators were reported within the subsurface horizontal flow unit (HF), playing a strategic role for Clostridium perfringens. The algal growth occurred in the free water surface (FWS) unit and inhibited removal efficiencies of total suspended solids (TSS), biochemical oxygen demand (BOD5) and chemical oxygen demand (COD), impairing water quality. The whole H-CW showed good efficiency in trace metals removal, especially for Pb, Zn, and Cu. Preliminary results suggested the reliability of the H-CW technology in decentralised water treatment facilities for enhancing water recovery and reuse.

Behavioral and genetic color vision evaluation of an albino male capuchin monkey (Sapajus apella).

Albinism is a rare phenotype that affects the pigmentation in eyes, hair, and skin. The effects of albinism in color vision are still unclear. Our study aimed to evaluate the color vision phenotype and genotype of an albino capuchin monkey. An adult albino male capuchin monkey (Sapajus apella) had the L and M opsin gene analyzed, and was trained in a behavioral task of color discrimination. Color discrimination thresholds were determined along 20 chromatic axes around the background chromaticity. A color discrimination ellipse was drawn by interpolation among these thresholds. The albino monkey's behavioral color discrimination ellipse showed poor discrimination along the red-green axis indicating a deutan phenotype. Genetic analysis revealed only the presence of the L gene in the albino monkey. This result did not differ from that obtained with ten previously tested non-albino monkeys. Behavioral and molecular analyses agreed that the albino capuchin monkey had color vision similar to that of non-albino dichromat monkeys, suggesting no influence of albinism on color discrimination.

Assessment of clogging in constructed wetlands by saturated hydraulic conductivity measurements.

This study aims at defining a methodology to evaluate Ks reductions of gravel material constituting constructed wetland (CW) bed matrices. Several schemes and equations for the Lefranc's test were compared by using different gravel sizes and at multiple spatial scales. The falling-head test method was implemented by using two steel permeameters: one impervious (IMP) and one pervious (P) on one side. At laboratory scale, mean K values for a small size gravel (8-15 × 10-2 m) measured by the IMP and the P permeameters were equal to 19,466 m/d and 30,662 m/d, respectively. Mean Ks values for a big size gravel (10-25 × 10-2 m) measured by the IMP and the P permeameters were equal to 12,135 m/d and 20,866 m/d, respectively. Comparison of Ks values obtained by the two permeameters at laboratory scale as well as a sensitivity analysis and a calibration, lead to the modification of the standpipe equation, to evaluate also the temporal variation of the horizontal Ks. In particular, both permeameters allow the evaluation of the Ks decreasing after 4 years-operation and 1-1.5 years' operation of the plants at full scale (filled with the small size gravel) and at pilot scale (filled with the big size gravel), respectively.

Hydraulic reliability of a horizontal wetland for wastewater treatment in Sicily.

The purpose of this study was to evaluate how the hydraulic behavior of a horizontal subsurface wetland (HF), that is part of the hybrid wetland (hybrid-TW) of the IKEA® store in Eastern Sicily (Italy), influences the overall wastewater treatment performance. The HF unit experiences frequent overloading peaks due to the extreme variability in the number of visitors at the store, and after 2 years of operation it showed signals of partial clogging at the inlet area. The hydraulics of the HF unit has been monitored through measurements of hydraulic conductivity at saturation (Ks), tracer tests, and geophysical (i.e. electrical resistivity tomography-ERT) measurements carried out during the years 2016 and 2017. Results indicated a general good agreement between the performed measurement techniques, thus their combination, if adequately performed and calibrated, might be a reliable tool for detecting those wetland areas mainly affected by clogging conditions. The results also indicated that partial clogging had no significant effect on the quality of the discharged water.

Daily activity patterns influence retinal morphology, signatures of selection, and spectral tuning of opsin genes in colubrid snakes.

BACKGROUND: Morphological divergences of snake retinal structure point to complex evolutionary processes and adaptations. The Colubridae family has a remarkable variety of retinal structure that can range from all-cone and all-rod to duplex (cone/rod) retinas. To explore whether nocturnal versus diurnal activity is responsible for constraints on molecular evolution and plays a role in visual opsin spectral tuning of colubrids, we carried out molecular evolution analyses of the visual opsin genes LWS, RH1, and SWS1 from 17 species and performed morphological analyses. RESULTS: Phylogenetic reconstructions of the RH1 and LWS recovered major clades characterized by primarily diurnal or primarily nocturnal activity patterns, in contrast with the topology for SWS1, which is very similar to the species tree. We found stronger signals of purifying selection along diurnal and nocturnal lineages for RH1 and SWS1, respectively. A blue-shift of the RH1 spectral peak is associated with diurnal habits. Spectral tuning of cone opsins did not differ among diurnal and nocturnal species. Retinas of nocturnal colubrids had many rows of photoreceptor nuclei, with large numbers of rods, labeled by wheat germ agglutinin (WGA), and two types of cones: large cones sensitive to long/medium wavelengths (L/M) and small cones sensitive to ultra-violet/violet wavelengths (UV/VS). In contrast, retinas of diurnal species had only one row of photoreceptor nuclei, with four types of cones: large and double L/M cones, small UV/VS cones, and a second group of small cones, labeled by WGA. CONCLUSIONS: For LWS gene, selection tests did not confirm different constraints related to activity pattern. For SWS1, stronger purifying selection in nocturnal lineages indicates divergent evolutionary pressures related to the activity pattern, and the importance of the short wavelength sensitivity at low light condition. Activity pattern has a clear influence on the signatures of selection and spectral tuning of RH1, with stronger purifying selection in diurnal lineages, which indicates selective pressure to preserve rhodopsin structure and function in pure-cone retinas. We suggest that the presence of four cone types in primarily diurnal colubrids might be related to the gain of color discrimination capacity.

Superficial swab versus deep-tissue biopsy for the microbiological diagnosis of local infection in advanced-stage pressure ulcers of spinal-cord-injured patients: a prospective study.

OBJECTIVE: To assess the predictive value of superficial ulcer swab culture to make a microbiological diagnosis of deep wound infections in spinal cord injury (SCI) patients with advanced-stage pressure ulcers. METHODS: From July 2011 to February 2014, we performed a prospective, single-centre study on adult SCI patients undergoing scheduled surgical debridement and reconstruction for advanced-stage pressure ulcers, at Montecatone Rehabilitation Institute, a 150-bed hospital dedicated to SCI care. Three superficial ulcer swabs were preoperatively collected using the Levine technique, then sent for culture. In surgery, multiple bone and soft-tissue specimens were taken and sent for culture and histological examination. No antibiotics were administered before surgery. The results of swabs and intraoperative specimens were compared. RESULTS: In all, 116 patients were included, median age 49 years; a majority were males with post-traumatic paraplegia. According to intraoperative specimen cultures, the most common micro-organisms were Staphylococcus aureus, Proteus mirabilis, and Pseudomonas aeruginosa, found in 31, 27, and 16 cases, respectively. Concordance between superficial swabs and intraoperative specimen culture was found in only in 25 out of 116 cases (22%). The main reason for non-concordance was the yielding of different micro-organisms (41 out of 116); false negatives (swab negative/intraoperative positive) accounted for 31 out of 116 and false positives (swab positive/intraoperative negative) for 19 out of 116. When compared with intraoperative specimens, sensitivity and specificity of the swab culture were 80% and 54%, respectively. CONCLUSIONS: Our results confirm that in patients with advanced-stage pressure ulcers, the cultures of a superficial ulcer swab are not useful in either the diagnosis of a superinfection or the prediction of the role of involved micro-organisms.

Possible relationship between certolizumab pegol and arrhythmias: report of two cases.

It is still unknown whether there is an association between the use of certolizumab pegol (CZP) in rheumatic patients and the onset of cardiac arrhythmias. We describe the cases of two patients with rheumatoid arthritis (RA) treated with CZP as the first-line biological drug and methotrexate (MTX), who developed an arrhythmic event. The first was a 60-year-old, hypertensive male smoker, the second a 66-year-old dyslipidemic female non-smoker. Both were diagnosed as having RA in 2010, and started treatment with MTX plus CZP. The first patient developed undatable atrial fibrillation, which was resistant to pharmacological treatment and electrical cardioversion. The second patient developed an atrial flutter, which was treated with a betablocker. In both cases, we set a cautious interval between two consecutive administrations of CZP and, in the first case, also reduced the dose of MTX without any worsening of RA activity. Although many studies have shown that tumor necrosis factor (TNF)-alpha plays a pathogenetic role in inducing an arrhythmogenic substrate that is apparently rescued by anti-TNF drugs, there is still a lack of conclusive data. We suggest caution in any patient developing a cardiac event (including rhythm disorders) during treatment with a conventional or biological disease-modifying anti-rheumatic drug.

Environmental exposure to arsenic and chromium in children is associated with kidney injury molecule-1.

Environmental hazards from natural or anthropological sources are widespread, especially in the north-central region of Mexico. Children represent a susceptible population due to their unique routes of exposure and special vulnerabilities. In this study we evaluated the association of exposure to environmental kidney toxicants with kidney injury biomarkers in children living in San Luis Potosi (SLP), Mexico. A cross-sectional study was conducted with 83 children (5-12 years of age) residents of Villa de Reyes, SLP. Exposure to arsenic, cadmium, chromium, fluoride and lead was assessed in urine, blood and drinking water samples. Almost all tap and well water samples had levels of arsenic (81.5%) and fluoride (100%) above the permissible levels recommended by the World Health Organization. Mean urine arsenic (45.6ppb) and chromium (61.7ppb) were higher than the biological exposure index, a reference value in occupational settings. Using multivariate adjusted models, we found a dose-dependent association between kidney injury molecule-1 (KIM-1) across chromium exposure tertiles [(T1: reference, T2: 467pg/mL; T3: 615pg/mL) (p-trend=0.001)]. Chromium upper tertile was also associated with higher urinary miR-200c (500 copies/µl) and miR-423 (189 copies/µL). Arsenic upper tertile was also associated with higher urinary KIM-1 (372pg/mL). Other kidney injury/functional biomarkers such as serum creatinine, glomerular filtration rate, albuminuria, neutrophil gelatinase-associated lipocalin and miR-21 did not show any association with arsenic, chromium or any of the other toxicants evaluated. We conclude that KIM-1 might serve as a sensitive biomarker to screen children for kidney damage induced by environmental toxic agents.

Chromatic spatial contrast sensitivity estimated by visual evoked cortical potential and psychophysics.

The purpose of the present study was to measure contrast sensitivity to equiluminant gratings using steady-state visual evoked cortical potential (ssVECP) and psychophysics. Six healthy volunteers were evaluated with ssVECPs and psychophysics. The visual stimuli were red-green or blue-yellow horizontal sinusoidal gratings, 5° × 5°, 34.3 cd/m2 mean luminance, presented at 6 Hz. Eight spatial frequencies from 0.2 to 8 cpd were used, each presented at 8 contrast levels. Contrast threshold was obtained by extrapolating second harmonic amplitude values to zero. Psychophysical contrast thresholds were measured using stimuli at 6 Hz and static presentation. Contrast sensitivity was calculated as the inverse function of the pooled cone contrast threshold. ssVECP and both psychophysical contrast sensitivity functions (CSFs) were low-pass functions for red-green gratings. For electrophysiology, the highest contrast sensitivity values were found at 0.4 cpd (1.95 ± 0.15). ssVECP CSF was similar to dynamic psychophysical CSF, while static CSF had higher values ranging from 0.4 to 6 cpd (P < 0.05, ANOVA). Blue-yellow chromatic functions showed no specific tuning shape; however, at high spatial frequencies the evoked potentials showed higher contrast sensitivity than the psychophysical methods (P < 0.05, ANOVA). Evoked potentials can be used reliably to evaluate chromatic red-green CSFs in agreement with psychophysical thresholds, mainly if the same temporal properties are applied to the stimulus. For blue-yellow CSF, correlation between electrophysiology and psychophysics was poor at high spatial frequency, possibly due to a greater effect of chromatic aberration on this kind of stimulus.

Chromatic spatial contrast sensitivity estimated by visual evoked cortical potential and psychophysics

The purpose of the present study was to measure contrast sensitivity to equiluminant gratings using steady-state visual evoked cortical potential (ssVECP) and psychophysics. Six healthy volunteers were evaluated with ssVECPs and psychophysics. The visual stimuli were red-green or blue-yellow horizontal sinusoidal gratings, 5° × 5°, 34.3 cd/m2 mean luminance, presented at 6 Hz. Eight spatial frequencies from 0.2 to 8 cpd were used, each presented at 8 contrast levels. Contrast threshold was obtained by extrapolating second harmonic amplitude values to zero. Psychophysical contrast thresholds were measured using stimuli at 6 Hz and static presentation. Contrast sensitivity was calculated as the inverse function of the pooled cone contrast threshold. ssVECP and both psychophysical contrast sensitivity functions (CSFs) were low-pass functions for red-green gratings. For electrophysiology, the highest contrast sensitivity values were found at 0.4 cpd (1.95 ± 0.15). ssVECP CSF was similar to dynamic psychophysical CSF, while static CSF had higher values ranging from 0.4 to 6 cpd (P < 0.05, ANOVA). Blue-yellow chromatic functions showed no specific tuning shape; however, at high spatial frequencies the evoked potentials showed higher contrast sensitivity than the psychophysical methods (P < 0.05, ANOVA). Evoked potentials can be used reliably to evaluate chromatic red-green CSFs in agreement with psychophysical thresholds, mainly if the same temporal properties are applied to the stimulus. For blue-yellow CSF, correlation between electrophysiology and psychophysics was poor at high spatial frequency, possibly due to a greater effect of chromatic aberration on this kind of stimulus.

Comparison of the reliability of multifocal visual evoked cortical potentials generated by pattern reversal and pattern pulse stimulation

This study compared the effectiveness of the multifocal visual evoked cortical potentials (mfVEP) elicited by pattern pulse stimulation with that of pattern reversal in producing reliable responses (signal-to-noise ratio >1.359). Participants were 14 healthy subjects. Visual stimulation was obtained using a 60-sector dartboard display consisting of 6 concentric rings presented in either pulse or reversal mode. Each sector, consisting of 16 checks at 99% Michelson contrast and 80 cd/m² mean luminance, was controlled by a binary m-sequence in the time domain. The signal-to-noise ratio was generally larger in the pattern reversal than in the pattern pulse mode. The number of reliable responses was similar in the central sectors for the two stimulation modes. At the periphery, pattern reversal showed a larger number of reliable responses. Pattern pulse stimuli performed similarly to pattern reversal stimuli to generate reliable waveforms in R1 and R2. The advantage of using both protocols to study mfVEP responses is their complementarity: in some patients, reliable waveforms in specific sectors may be obtained with only one of the two methods. The joint analysis of pattern reversal and pattern pulse stimuli increased the rate of reliability for central sectors by 7.14% in R1, 5.35% in R2, 4.76% in R3, 3.57% in R4, 2.97% in R5, and 1.78% in R6. From R1 to R4 the reliability to generate mfVEPs was above 70% when using both protocols. Thus, for a very high reliability and thorough examination of visual performance, it is recommended to use both stimulation protocols.

Comparison of the reliability of multifocal visual evoked cortical potentials generated by pattern reversal and pattern pulse stimulation.

This study compared the effectiveness of the multifocal visual evoked cortical potentials (mfVEP) elicited by pattern pulse stimulation with that of pattern reversal in producing reliable responses (signal-to-noise ratio >1.359). Participants were 14 healthy subjects. Visual stimulation was obtained using a 60-sector dartboard display consisting of 6 concentric rings presented in either pulse or reversal mode. Each sector, consisting of 16 checks at 99% Michelson contrast and 80 cd/m² mean luminance, was controlled by a binary m-sequence in the time domain. The signal-to-noise ratio was generally larger in the pattern reversal than in the pattern pulse mode. The number of reliable responses was similar in the central sectors for the two stimulation modes. At the periphery, pattern reversal showed a larger number of reliable responses. Pattern pulse stimuli performed similarly to pattern reversal stimuli to generate reliable waveforms in R1 and R2. The advantage of using both protocols to study mfVEP responses is their complementarity: in some patients, reliable waveforms in specific sectors may be obtained with only one of the two methods. The joint analysis of pattern reversal and pattern pulse stimuli increased the rate of reliability for central sectors by 7.14% in R1, 5.35% in R2, 4.76% in R3, 3.57% in R4, 2.97% in R5, and 1.78% in R6. From R1 to R4 the reliability to generate mfVEPs was above 70% when using both protocols. Thus, for a very high reliability and thorough examination of visual performance, it is recommended to use both stimulation protocols.

Manifold Learning by Graduated Optimization.

We present an algorithm for manifold learning called manifold sculpting , which utilizes graduated optimization to seek an accurate manifold embedding. An empirical analysis across a wide range of manifold problems indicates that manifold sculpting yields more accurate results than a number of existing algorithms, including Isomap, locally linear embedding (LLE), Hessian LLE (HLLE), and landmark maximum variance unfolding (L-MVU), and is significantly more efficient than HLLE and L-MVU. Manifold sculpting also has the ability to benefit from prior knowledge about expected results.

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 an ultraviolet (UV) channel and a tetrachromatic visual system. Our laboratory has been working in 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.

Psychophysical analysis of contrast processing segregated into magnocellular and parvocellular systems in asymptomatic carriers of 11778 Leber's hereditary optic neuropathy.

We examined achromatic contrast discrimination in asymptomatic carriers of 11778 Leber's hereditary optic neuropathy (LHON 18 controls) and 18 age-match were also tested. To evaluate magnocellular (MC) and Parvocellular (PC) contrast discrimination, we used a version of Pokorny and Smith's (1997) pulsed/steady-pedestal paradigms (PPP/SPP) thought to be detected via PC and MC pathways, respectively. A luminance pedestal (four 1 degree x 1 degree squares) was presented on a 12 cd/m2 surround. The luminance of one of the squares (trial square, TS) was randomly incremented for either 17 or 133 ms. Observers had to detect the TS, in a forced-choice task, at each duration, for three pedestal levels: 7, 12, 19 cd/m2. In the SPP, the pedestal was fixed, and the TS was modulated. For the PPP, all four pedestal squares pulsed for 17 or 133 ms, and the TS was simultaneously incremented or decremented. We found that contrast discrimination thresholds of LHON carriers were significantly higher than controls' in the condition with the highest luminance of both paradigms, implying impaired contrast processing with no evidence of differential sensitivity losses between the two systems. Carriers' thresholds manifested significantly longer temporal integration than controls in the SPP, consistent with slowed MC responses. The SPP and PPP paradigms can identify contrast and temporal processing deficits in asymptomatic LHON carriers, and thus provide an additional tool for early detection and characterization of the disease.