196 research outputs found

    Telephone conversation impairs sustained visual attention via a central bottleneck

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    Recent research has shown that holding telephone conversations disrupts one's driving ability. We asked whether this effect could be attributed to a visual attention impairment. In Experiment 1, participants conversed on a telephone or listened to a narrative while engaged in multiple object tracking (MOT), a task requiring sustained visual attention. We found that MOT was disrupted in the telephone conversation condition, relative to single-task MOT performance, but that listening to a narrative had no effect. In Experiment 2, we asked which component of conversation might be interfering with MOT performance. We replicated the conversation and single-task conditions of Experiment 1 and added two conditions in which participants heard a sequence of words over a telephone. In the shadowing condition, participants simply repeated each word in the sequence. In the generation condition, participants were asked to generate a new word based on each word in the sequence. Word generation interfered with MOT performance, but shadowing did not. The data indicate that telephone conversation disrupts attention at a central stage, the act of generating verbal stimuli, rather than at a peripheral stage, such as listening or speaking

    Fully integrated high quality factor GmC bandpass filter stage with highly linear operational transconductance amplifier

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    This paper presents an electrical, fully integrated, high quality (Q) factor GmC bandpass filter (BPF) stage for a wireless 27 MHz direct conversion receiver for a bendable sensor system-in-foil (Briem, 2016). The core of 10 the BPF with a Q factor of more than 200 is an operational transconductance amplifier (OTA) with a high linearity at an input range of up to 300 mVpp,diff. The OTA’s signal-to-noise-and-distortion-ratio (SNDR) of more than 80 dB in the mentioned range is achieved by stabilizing its transconductance Gm with a respective feedback loop and a source degeneration resistance RDG. The filter stage can be tuned and is tolerant to global and local process variations due to offset and common-mode 15 feedback (CMFB) control circuits. The results are determined by periodic steady state (PSS) simulations at more than 200 global and local process variation parameter and temperature points and corner simulations. It is expected, that the parasitic elements of the layout have no significant influence on the filter behaviour. The current consumption of the whole filter stage is less than 600 μA

    Detection and monitoring of Drosophila suzukii in raspberry and cherry orchards with volatile organic compounds in the USA and Europe

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    Spotted wing drosophila (SWD) causes significant economic loss in fruit crops to growers worldwide. There is immediate need for efficacious and selective monitoring tools that can detect infestations early. Previously, volatile organic compounds derived from apple were studied and a quinary chemical component blend (QB) was identified as the key SWD attractant in a blueberry orchard in the United States. This study’s aim was to determine whether previously observed QB efficacy, selectivity, and early detection levels could be attained within raspberry and cherry fields in the USA and Europe. Results demonstrated that sticky trap baited QB dispenser provided earlier SWD detection potential than the usually adopted apple cider vinegar (ACV) trap. The number of SWD captured/trap by QB baited trapping systems was significantly lower than that of the ACV trap. However, percent SWD/trap of QB baited traps was same within cherry. Lower non-target capture will save farmer/grower’s labor and time allocated to traps installation and drosophila species identification. Within the USA, SWD selectivity of QB baited liquid traps was consistently greater than sticky trap in raspberry field, suggesting that the QB dispenser can be an alternative to the standard ACV lure and that trap design could improve selectivity further.info:eu-repo/semantics/publishedVersio

    Ligand-independent oligomerization of TACI is controlled by the transmembrane domain and regulates proliferation of activated B cells.

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    In mature B cells, TACI controls class-switch recombination and differentiation into plasma cells during T cell-independent antibody responses. TACI binds the ligands BAFF and APRIL. Approximately 10% of patients with common variable immunodeficiency (CVID) carry TACI mutations, of which A181E and C172Y are in the transmembrane domain. Residues A181 and C172 are located on distinct sides of the transmembrane helix, which is predicted by molecular modeling to spontaneously assemble into trimers and dimers. In human B cells, these mutations impair ligand-dependent (C172Y) and -independent (A181E) TACI multimerization and signaling, as well as TACI-enhanced proliferation and/or IgA production. Genetic inactivation of TACI in primary human B cells impaired survival of CpG-activated cells in the absence of ligand. These results identify the transmembrane region of TACI as an active interface for TACI multimerization in signal transduction, in particular for ligand-independent signals. These functions are perturbed by CVID-associated mutations

    2D-fluoroscopic navigated percutaneous screw fixation of pelvic ring injuries - a case series

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    <p>Abstract</p> <p>Background</p> <p>Screw fixation of pelvic ring fractures is a common, but demanding procedure and navigation techniques were introduced to increase the precision of screw placement. The purpose of this case series was the evaluation of screw misplacement rate and functional outcome of percutaneous screw fixation of pelvic ring disruptions using a 2D navigation system.</p> <p>Methods</p> <p>Between August 2004 and December 2007, 44 of 442 patients with pelvic injuries were included for closed reduction and percutaneous screw fixation of disrupted pelvic ring lesions using an optoelectronic 2D-fluoroscopic based navigation system. Operating and fluoroscopy time were measured, as well as peri- and postoperative complications documented. Screw position was assessed by postoperative CT scans. Quality of live was evaluated by SF 36-questionnaire in 40 of 44 patients at mean follow up 15.5 ± 1.2 month.</p> <p>Results</p> <p>56 iliosacral- and 29 ramus pubic-screws were inserted (mean operation time per screw 62 ± 4 minutes, mean fluoroscopy time per screw 123 ± 12 seconds). In post-operative CT-scans the screw position was assessed and graded as follows: I. secure positioning, completely in the cancellous bone (80%); II. secure positioning, but contacting cortical bone structures (14%); III. malplaced positioning, penetrating the cortical bone (6%). The malplacements predominantly occurred in bilateral overlapping screw fixation. No wound infection or iatrogenic neurovascular damage were observed. Four re-operations were performed, two of them due to implant-misplacement and two of them due to implant-failure.</p> <p>Conclusion</p> <p>2D-fluoroscopic navigation is a safe tool providing high accuracy of percutaneous screw placement for pelvic ring fractures, but in cases of a bilateral iliosacral screw fixation an increased risk for screw misplacement was observed. If additional ramus pubic screw fixations are performed, the retrograde inserted screws have to pass the iliopubic eminence to prevent an axial screw loosening.</p

    Combined Anterior-Posterior Surgery Versus Posterior Surgery for Thoracolumbar Burst Fractures: A Systematic Review of the Literature

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    Abstract: Study Design: A systematic quantitative review of the literature. Objective: To compare combined anterior-posterior surgery versus posterior surgery for thoracolumbar fractures in order to identify better treatments. Summary of Background Data: Axial load of the anterior and middle column of the spine can lead to a burst fracture in the vertebral body. The management of thoracolumbar burst fractures remains controversial. The goals of operative treatment are fracture reduction, fixation and decompressing the neural canal. For this, different operative methods are developed, for instance, the posterior and the combined anterior-posterior approach. Recent systematic qualitative reviews comparing these methods are lacking. Methods: We conducted an electronic search of MEDLINE, EMBASE, LILACS and the Cochrane Central Register for Controlled Trials. Results: Five observational comparative studies and no randomized clinical trials comparing the combined anteriorposterior approach with the posterior approach were retrieved. The total enrollment of patients in these studies was 755 patients. The results were expressed as relative risk (RR) for dichotomous outcomes and weighted mean difference (WMD) for continuous outcomes with 95% confidence intervals (CI). Conclusions: A small significantly higher kyphotic correction and improvement of vertebral height (sagittal index) observed for the combined anterior-posterior group is cancelled out by more blood loss, longer operation time, longer hospital stay, higher costs and a possible higher intra- and postoperative complication rate requiring re-operation and the possibility of a worsened Hannover spine score. The surgeons’ choices regarding the operative approach are biased: worse cases tended to undergo the combined anterior-posterior approach

    Rapid assessment of Hib disease burden in Vietnam

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    <p>Abstract</p> <p>Background</p> <p>Several countries have applied the <it>Haemophilus influenzae </it>type b (Hib) rapid assessment tool (RAT) to estimate the burden of Hib disease where resources for hospital- or population-based surveillance are limited. In Vietnam, we used the Hib RAT to estimate the burden of Hib pneumonia and meningitis prior to Hib vaccine introduction.</p> <p>Methods</p> <p>Laboratory, hospitalization and mortality data were collected for the period January 2004 through December 2005 from five representative hospitals. Based on the WHO Hib RAT protocol, standardized MS Excel spreadsheets were completed to generate meningitis and pneumonia case and death figures.</p> <p>Results</p> <p>We found 35 to 77 Hib meningitis deaths and 441 to 957 Hib pneumonia deaths among children < 5 years of age annually in Vietnam. Overall, the incidence of Hib meningitis was estimated at 18/100,000 (95% confidence interval, CI, 15.1-21.6). The estimated Hib meningitis incidence in children < 5 years age was higher in Ho Chi Minh City (22.5/100,000 [95% CI, 18.4-27.5]) compared to Hanoi (9.8/100,000 [95% CI, 6.5-14.8]). The Hib RAT suggests that there are a total of 883 to 1,915 cases of Hib meningitis and 4,414 to 9,574 cases of Hib pneumonia per year in Vietnam.</p> <p>Conclusions</p> <p>In Hanoi, the estimated incidence of Hib meningitis for children < 5 years of age was similar to that described in previous population-based studies of Hib meningitis conducted from 1999 through 2002. Results from the Hib RAT suggest that there is a substantial, yet unmeasured, disease burden associated with Hib pneumonia in Vietnamese children.</p

    Evaluation of a novel nanocrystalline hydroxyapatite paste Ostim® in comparison to Alpha-BSM® - more bone ingrowth inside the implanted material with Ostim® compared to Alpha BSM®

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    <p>Abstract</p> <p>Background</p> <p>The purpose of this study was to evaluate the performance a newly developed nanocrystalline hydroxyapatite, OSTIM<sup>® </sup>following functional implantation in femoral sites in thirty-eight sheep for 1, 2 or 3 months. Ostim<sup>® </sup>35 was compared to an established calcium phosphate, Alpha BSM<sup>®</sup>.</p> <p>Methods</p> <p>Biomechanical testing, μ-CT analysis, histological and histomorphological analyses were conducted to compare the treatments including evaluation of bone regeneration level, material degradation, implant biomechanical characteristics.</p> <p>Results</p> <p>The micro-computed tomography (μCT) analysis and macroscopic observations showed that Ostim<sup>® </sup>seemed to diffuse easily particularly when the defects were created in a cancellous bone area. Alpha BSM<sup>® </sup>remained in the defect.</p> <p>The performance of Ostim was good in terms of mechanical properties that were similar to Alpha BSM<sup>® </sup>and the histological analysis showed that the bone regeneration was better with Ostim<sup>® </sup>than with Alpha BSM<sup>®</sup>. The histomorphometric analysis confirmed the qualitative analysis and showed more bone ingrowth inside the implanted material with Ostim<sup>® </sup>when compared to Alpha BSM <sup>® </sup>at all time points.</p> <p>Conclusions</p> <p>The successful bone healing with osseous consolidation verifies the importance of the nanocrystalline hydroxyapatite in the treatment of metaphyseal osseous volume defects in the metaphyseal spongiosa.</p

    Analysis and results of 282 one stage exchange procedures for periprosthetic infection of the hip and knee

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