Boundary completion is automatic and dissociable from shape discrimination

Normal visual perception readily overcomes suboptimal or degraded viewing conditions through perceptual filling-in processes, enhancing object recognition and discrimination abilities. This study used visual evoked potential (VEP) recordings in conjunction with electrical neuroimaging analyses to determine the spatiotemporal brain dynamics of boundary completion and shape discrimination processes in healthy humans performing the so-called "thin/fat" discrimination task (Ringach and Shapley, 1996) with stimuli producing illusory contours. First, results suggest that boundary completion processes occur independent of subjects' accuracy on the discrimination task. Modulation of the VEP to the presence versus absence of illusory contours [the IC effect (Murray et al., 2002)] was indistinguishable in terms of response magnitude and scalp topography over the 124-186 ms poststimulus period, regardless of whether task performance was correct. This suggests that failure on this discrimination task is not primarily a consequence of failed boundary completion. Second, the electrophysiological correlates of thin/fat shape discrimination processes are temporally dissociable from those of boundary completion, occurring during a substantially later phase of processing (approximately 330-406 ms). The earlier IC effect was unaffected by whether the perceived contour produced a thin or fat shape. In contrast, later time periods of the VEP modulated according to perceived shape only in the case of stimuli producing illusory contours, but not for control stimuli for which performance was at near-chance levels. Collectively, these data provide further support for a multistage model of object processing under degraded viewing conditions

Excitation thresholds of field-aligned irregularities and associated ionospheric hysteresis at very high latitudes observed using SPEAR-induced HF radar backscatter

On 10 October 2006 the SPEAR high power radar facility was operated in a power-stepping mode where both CUTLASS radars were detecting backscatter from the SPEAR-induced field-aligned irregularities (FAIs). The effective radiated power of SPEAR was varied from 1–10 MW. The aim of the experiment was to investigate the power thresholds for excitation (<I>P<sub>t</sub></I>) and collapse (<I>P<sub>c</sub></I>) of artificially-induced FAIs in the ionosphere over Svalbard. It was demonstrated that FAI could be excited by a SPEAR ERP of only 1 MW, representing only 1/30th of SPEAR's total capability, and that once created the irregularities could be maintained for even lower powers. The experiment also demonstrated that the very high latitude ionosphere exhibits hysteresis, where the down-going part of the power cycle provided a higher density of irregularities than for the equivalent part of the up-going cycle. Although this second result is similar to that observed previously by CUTLASS in conjunction with the Tromsø heater, the same is not true for the equivalent incoherent scatter measurements. The EISCAT Svalbard Radar (ESR) failed to detect any hysteresis in the plasma parameters over Svalbard in stark contract with the measurements made using the Tromsø UHF

Brood patch and sex-ratio observations indicate breeding provenance and timing in New Zealand storm petrel (Fregetta maoriana)

We used measurements of brood patch and moult status to estimate the breeding phenology of New Zealand Storm-Petrel, using birds caught at sea within the Hauraki Gulf Marine Park near Auckland, New Zealand. Birds caught October–January had completely downy brood patches, whereas birds caught February–April had bare brood patches with an observed male bias in the February sex-ratio, consistent with a female pre-laying exodus typical of petrels and with the existence of an unknown colony in the region. No birds captured exhibited primary moult, which is known to occur in storm-petrels during their non-breeding season. Our data support the conclusion that the New Zealand storm-petrel breeds during January–June in northern New Zealand and that field surveys for the species on offshore islands in this region during this period are warrante

Demonstration of Calreticulin Expression in Hamster Pancreatic Adenocarcinoma with the Use of Fluorescent Gold Quantum Dots

BACKGROUND: There is dire need for discovery of novel pancreatic cancer biomarkers and of agents with the potential for simultaneous diagnostic and therapeutic capacity. This study demonstrates calreticulin expression on hamster pancreatic adenocarcinoma via bio-conjugated gold quantum dots (AuQDs). MATERIALS AND METHODS: Hamster pancreatic adenocarcinoma cells were cultured, fixed and incubated with fluorescent AuQDs, bio-conjugated to anti-calreticulin antibodies. Anti-calreticulin and AuQDs were produced in-house. AuQDs were manufactured to emit in the near-infrared. Cells were further characterized under confocal fluorescence. RESULTS: AuQDs were confirmed to emit in the near-infrared. AuQD bio-conjugation to calreticulin was confirmed via dot-blotting. Upon laser excitation and post-incubation with bio-conjugated AuQDs, pancreatic cancer cell lines emitted fluorescence in near-infrared. CONCLUSION: Hamster pancreatic cancer cells express calreticulin, which may be labelled with AuQDs. This study demonstrates the application of nanoparticle-based theranostics in pancreatic cancer. Such biomarker-targeting nanosystems are anticipated to play a significant role in the management of pancreatic cancer

Combining Donor and Recipient Age With Preoperative MELD and UKELD Scores for Predicting Survival After Liver Transplantation

Objectives: The end-stage liver disease scoring systems MELD, UKELD, and D-MELD (donor age × MELD) have had mediocre results for survival assessment after orthotopic liver transplant. Here, we introduced new indices based on preoperative MELD and UKELD scores and assessed their predictive ability on survival posttransplant. Materials and Methods: We included 1017 deceased donor orthotopic liver transplants that were performed between 2008 (the year UKELD was introduced) and 2019. Donor and recipient characteristics, liver disease scores, transplant characteristics, and outcomes were collected for analyses. D-MELD, D-UKELD (donor age × UKELD), DR-MELD [(donor age + recipient age) × MELD], and DR-UKELD [(donor age + recipient age) × UKELD] were calculated. Results: No score had predictive value for graft survival. For patient survival, DR-MELD and DR-UKELD provided the best results but with low accuracy. The highest accuracy was observed at 1 year posttransplant (areas under the curve of 0.598 [95% CI, 0.529-0.667] and 0.609 [95% CI, 0.549-0.67] for DR-MELD and DR-UKELD). Addition of donor and recipient age significantly improved the predictive abilities of MELD and UKELD for patient survival, but addition of donor age alone did not. For 1-year mortality (using receiver operating characteristic curves), optimal cut-off points were DR-MELD >2345 and DR-UKELD >5908. Recipients with DR-MELD >2345 (P 5908 (P = .002) had worse patient survival within the first year, but only DR-MELD >2345 remained significant after multiva­riable analysis (P = .007). Conclusions: DR-MELD and DR-UKELD scores provided the best, albeit mediocre, predictive ability among the 6 tested models, especially at 1 year after posttransplant, although only for patient but not for graft survival. A DR-MELD >2345 was considered to be an additional independent risk factor for worse recipient survival within the first postoperative year

Recession coverage using the modified coronally advanced tunnel and connective tissue graft with or without enamel matrix derivative: 5-year results of a randomised clinical trial.

OBJECTIVES To evaluate the 5-year results of single and multiple recession type (RT) 1 and 2 (Miller I to III) recessions treated with the modified coronally advanced tunnel (MCAT) and connective tissue graft (CTG) with or without an enamel matrix derivative (EMD). The main outcome variable was the stability of obtained root coverage from 6 months to 5 years. MATERIALS AND METHODS In 24 patients, both complete and mean root coverage (CRC and MRC) and gain of keratinised tissue (KT) were assessed at 6 months and 5 years after recession coverage by means of MCAT and CTG with or without EMD. Aesthetic outcomes after 5 years were evaluated using the root coverage aesthetic score (RES). RESULTS At 5 years, 24 patients with a total of 43 recessions were evaluated. Eight patients (57.14%) of the test and 6 (60.0%) of the control group showed complete root coverage. MRC revealed no statistically significant differences between the two groups, with 73.87 ± 26.83% (test) and 75.04 ± 22.06% (control), respectively. KT increased from 1.14 ± 0.57 mm to 3.07 ± 2.27 mm in the test group and from 1.24 ± 0.92 mm to 3.02 ± 1.55 mm in the control group, respectively. CONCLUSION Treatment of single and multiple RT 1 and 2 recessions by means of MCAT and CTG with or without EMD yielded comparable clinical improvements which could be maintained over a period of 5 years. The additional use of EMD did not influence the clinical outcomes. CLINICAL RELEVANCE The use of MCAT + CTG yielded successful coverage of single and multiple RT 1 and 2 gingival recessions, while the additional application of EMD did not seem to influence the results

Donor-Recipient Body Surface Area Mismatch and the Outcome of Liver Transplantation in the UK

Introduction: Too small or too big liver grafts for recipient's size has detrimental effects on transplant outcomes. Research Questions: The purpose was to correlate donor-recipient body surface area (BSA) ratio or BSA index (BSAi) with recipient survival, graft survival, hepatic artery or portal vein, or vena cava thrombosis. High and low BSAi cut-off points were determined. Design: There were 11,245 adult recipients of first deceased donor whole liver-only grafts performed in the UK from January 2000 until June 2020. The transplants were grouped according to the BSAi and compared to complications, graft and recipient survival. Results: The BSAi ranged from 0.491 to 1.691 with a median of 0.988. The BSAi > 1.3 was associated with a higher rate of portal vein thrombosis within the first 3 months (5.5%). This risk was higher than size-matched transplants (OR: 2.878, 95% CI: 1.292-6.409, P = 0.01). Overall graft survival was worse in transplants with BSAi ≤ 0.85 (HR: 1.254, 95% CI: 1.051-1.497, P = 0.012) or BSAi > 1.4 (HR: 3.704, 95% CI: 2.029-6.762, P 1.4. These findings were confirmed by bootstrap internal validation. No statistically significant differences were detected for hepatic artery thrombosis, occlusion of hepatic veins/inferior vena cava or recipient survival. Conclusions: Donor-recipient size mismatch affects the rates of portal vein thrombosis within the first 3 months and overall graft survival in deceased-donor liver transplants