Slow Time Research Articles

Dual task iTUG to investigate increased fall risk among older adults with bilateral hearing loss.

To investigate fall risk among older adults with bilateral sensorineural hearing loss (BHL) by comparing single task (ST) and dual task (DT) performance on the instrumented "Timed Up & Go" test (iTUG). The TUG is a well-validated clinical tool for fall risk; addition of wireless sensors increases the test's sensitivity and allows for subcomponent analysis. Adults with audiometrically confirmed normal hearing or BHL were prospectively recruited and screened for visual, musculoskeletal, neurologic, or vestibular pathology and Dizziness Handicap Inventory (DHI)<10. Total and sub-component iTUG data in the ST and DT condition (serial subtraction) was collected. 35 adults (50-78years) were included: 20 (mean 69years) with BHL and 15 controls (mean age 63years). Total iTUG duration did not differ between groups in either the ST or DT condition. In sit-to-stand, BHL were significantly slower than controls (p<0.03) in both ST and DT conditions. In the final subcomponent (stand-to-sit), a significant interaction was observed such that the BHL group were significantly slower with DT compared to the control group. BHL performed slower on sub-component analysis of the iTUG compared with age-matched normal hearing controls. Slower times on the final iTUG phase for BHL may suggest a lower threshold for attentional capacity that may be cumulative. Further investigation into the impact of treatment (including amplification and training) is warranted.

Effects of diesel exhaust inhalation on cognitive performance in human volunteers: A randomized controlled crossover study.

Mounting evidence links exposure to traffic-related air pollution (TRAP) to impairment in cognitive functioning. To determine if short-term, controlled exposure to diesel exhaust (DE) adversely affects one or more cognitive function domains. We carried out a double-blinded crossover design with 28 healthy, adult volunteers. Volunteers were exposed to two conditions for 120min each, on separate order-randomized occasions: filtered air (FA) and DE (300µg/m3 PM2.5) at the Air Pollution Exposure Laboratory (APEL) at Vancouver General Hospital (VGH). Volunteers were blinded to the two exposure conditions. Volunteers completed five computerised neuropsychological tests of the Cambridge Neuropsychological Test Automated Battery (CANTAB) prior to (2-hr before) and at three timepoints following each exposure condition (0-hr, 3-h post-, and 24-h post-exposure). The selected CANTAB tests were related to five cognitive domains - attention, spatial working memory, strategy use, executive function, and processing speed. We hypothesized that short-term diesel exposure would adversely affect one or more cognitive function domains. Following screening, 15 volunteers were randomized to receive FA followed by DE and 14 volunteers were randomized to receive the exposures in the reverse sequence. A total of 28 volunteers contributed to the final analysis. Short-term exposure to DE was associated with slower reaction times in the Reaction Time Index task. DE was associated with a decrease of 18.2ms (p=0.05) in simple reaction time and 23.5ms (p=0.04) in five-choice reaction time. This first study to investigate the effects of TRAP on the cognitive performance of humans in a controlled environment shows slowed reaction times similar to those previously demonstrated with blood alcohol levels of 0.05%. Important implications exist for workers in occupations where attention and reaction time are connected to safety and performance.

Error monitoring under working memory load: Anelectrocortical investigation.

Error monitoring is essential for detecting errors and may facilitate behavioral adjustments that can reduce or prevent future errors. At times, error monitoring must occur while individuals are engaged in other, cognitively demanding tasks that might consume processing resources necessary for error monitoring. Here, we set out to determine whether concurrent working memory (WM) load interferes with error monitoring, as measured using event-related potentials, the error-related negativity (Ne/ERN), and error positivity (Pe). Fifty-four participants (n = 33 female) completed an arrowhead flanker task, with trials presented under low (2 letter) or high (6 letter) WM load. Participants were required to hold letter strings in memory and to recall these letters at the end of a set of flanker trials. Results showed that WM load reduced the Pe but did not affect the Ne/ERN. Therefore, WM load appeared to attenuate later, more elaborated stages of error processing, though initial error detection was unaffected. Additionally, high WM load slowed reaction times overall, but did not lead to a significant increase in errors. As such, slower responses may have helped participants maintain comparable accuracy for low-load versus high-load trials. Overall, results indicate that WM load interferes with the evaluation of error significance, which could interfere with behavioral adaptations over time.

Thermal biology of the endemic lizard Phymaturus verdugo: is it as conservative as we think?

Abstract Under the scenario of global climate change, understanding how animals cope with environmental changes might help to predict their future responses. The genus Phymaturus serves as a valuable model for studying thermal biology owing to its conservatism in thermal traits, despite its broad latitudinal distribution. By examining two geographically close populations of the lizard Phymaturus verdugo from the Andean mountains, we aimed to determine whether body mass, dorsal melanism, and microclimatic conditions influence their thermal biology. The species demonstrates moderate to good thermoregulation, with females increasing effectiveness in sites with lower thermal quality. Although their preferred temperature remained consistent across populations, significant differences in body temperature, effectiveness of thermoregulation, and heating times were observed. Melanism, proposed to enhance heating in cold environments, showed limited effects on thermoregulation, accelerating heating times only in specific conditions (males heating from 15°C to 35°C at the colder site). Instead, body mass emerged as the key factor that consistently slowed heating times. Our findings suggest that P. verdugo relies heavily on behavioural strategies for thermoregulation, allowing individuals to cope with immediate thermal variability, but the ability to adapt to future climate change remains uncertain, because these responses might provide short-term benefits but limit long-term physiological adaptation.

Layer-specific BOLD effects in gradient and spin-echo acquisitions in somatosensory cortex.

Previous studies have shown varied BOLD signals with gradient echo (GE) across cortical depth. To interpret these variations, and understand the effects of vascular geometry and size, the magnitudes and layer distributions of GE and spin-echo (SE) BOLD functional MRI signals were compared in the somatosensory cortex of squirrel monkeys during tactile stimulation and in a resting state at high spatial resolution and high field. A block-design stimulation was used to identify tactile-evoked activation signals in somatosensory Areas 3b and 1. Layer-specific connectivities were calculated using resting-state data. Signal power spectra were compared by depth and pulse sequence. The measured ratios of transverse relaxation rate changes were compared with Anderson and Weiss's model. SE signals showed a 26% lower percentage signal change during tactile stimulation compared with GE, along with a slower time course. SE signals remained consistent but weaker in lower layers, whereas GE signals decreased with cortical depth. This pattern extended to resting-state power spectra. Resting-state functional connectivity indicated larger connectivity between the top layers of Area 3b and Area 1 for GE, with minimal changes for SE. Comparisons with theory suggest vessel diameters ranging from 19.4 to 9 microns are responsible for BOLD effects across cortical layers at 9.4 T. These results provide further evidence that at high field, SE BOLD signals are relatively free of contributions from sources other than microvascular changes in response to neural activity, whereas GE signals, even in the superficial layers, are not dominated by very large vessels.

Overview of Path Planning Algorithms

Background: Path-planning algorithms are widely used in robotics, vehicles, UAVs, carrier-based aircraft towing vehicles, etc. Using these algorithms, an optimal path with safe obstacle avoidance and high efficiency can be planned. In recent years, path-planning algorithms have received more and more attention from scholars at home and abroad. Objective: In order to promote the application and development of path-planning algorithms, an in-depth analysis of the current development status of path-planning algorithms was presented. The most widely used and representative algorithms in several representative results were extracted, and the characteristics and advantages and disadvantages of each algorithm were analyzed and elaborated in detail for the readers' reference. Methods: The existing path-planning algorithms were classified, and a brief overview of each traditional algorithm was given, followed by an in-depth study of the improved algorithms to summarize the advantages and disadvantages of each type of algorithm. Finally, based on these research results, the future development trend of path-planning algorithms was projected. Results: Through the research and analysis of the path-planning algorithm, it was found that the path- planning algorithm before the improvement had the problems of an unsmooth path, low computational efficiency, a slow response time, the inability to safely avoid obstacles, etc. After the improvement and optimization of the path-planning algorithm, the performance was greatly improved. Conclusion: After research and analysis, it was found that multi-algorithm fusion had great potential for development in path-planning compared to the application and optimization of a single algorithm. In addition, further research is needed in the areas of algorithm adaptability, fusion, intelligent algorithms, and extending the range of algorithmic applications.

Hematological and performance adaptations to altitude training (2,320m) in elite middle-distance and distance swimmers.

Elite swimmers often schedule altitude training camps ahead of major events in an attempt to maximize performance. However, the relationships between altitude-induced hematological changes, markers of training adaptation, and performance changes in such context are unclear. This study assessed hematological status, markers of daily adaptation, and swimming performance in elite middle-distance and distance swimmers during a 22-day altitude training camp at 2,320m, 2weeks prior to World Championship qualification competition. Venous blood was obtained and total hemoglobin mass (tHbmass) measured (CO rebreathing) in 7 elite swimmers (4 females, 3 males) 8days before and on day 22 of the altitude camp. Resting heart rate, peripheral oxygen saturation, urinary specific gravity, body mass, fatigue and self-reported sleep duration and quality were monitored daily during the altitude camp. Swimming performance was assessed through a standardized set (6 sets of 4 maximal repetitions of 100m front crawl) on days 3, 10 and 17 of the camp, and at sea level competitions (200m-1,500m) immediately after the camp, and 2weeks later. tHbmass (+5.6 ± 3.3%; range: 2.1%-11.0%; p < 0.05), red blood cell count, hemoglobin concentration, hematocrit increased at the end of the training camp (p < 0.05). Performance at altitude improved throughout the camp (+1.4 ± 0.4%; range: 0.7%-2.5%; p < 0.05). No significant relationship was noted between hematological changes, the change in altitude performance and any of the monitored daily markers of adaptation during the camp. Compared to the swimmers' previous personal best, competition performances did not improve immediately (2.5% ± 1.9% slower times) and 2weeks after altitude (1.2% ± 1.4% slower times). The 22-day altitude training camp at 2,320m was beneficial for elite swimmers' tHbmass, hematological status and performance at altitude, but these benefits did not clearly translate into enhanced sea level performance immediately after or 2weeks later. The present study confirms the large inter-individual variability in hematological responses to altitude training, and that the improvement in performance at altitude and sea level may depend on factors other than the increase in tHbmass alone.

Time in suspense: investigating boredom and related states in a virtual waiting room

ABSTRACT We studied the role of time in the experience of boredom and its relationship with various psychological states using virtual reality. Sixty-six participants visited nine virtual waiting rooms and evaluated their perception of time and psychological experiences, including boredom, exhaustion, restlessness, amotivation, frustration, anger, unhappiness, spontaneous and deliberate mind-wandering, fantasy, and absorption. Results confirmed the relationship between boredom and time perception, showing that the higher the levels of boredom, the slower time seems to pass. However, manipulating time-related information via a slower/faster ticking clock did not affect boredom. We also found that boredom increased as participants progressed through the nine virtual rooms, and its affective characterisation over time remained stable, while its cognitive characterisation fluctuated. While boredom was consistently associated with exhaustion, restlessness, amotivation, and frustration, its relationship with fantasy, absorption, spontaneous mind-wandering and deliberate mind-wandering, evolved over time. These findings provide novel insights into the intricate and differentiated cognitive and affective consequences of being bored.

Paralympic Versus Olympic Canoe Sprint: Comprehension of the Development Trajectory of the Kayak 200 Meters.

Improvements in race times for male and female Para canoe athletes across different sports classes have led to a reduction in relative differences between classes over time. However, there is a lack of research examining the comparative developmental trajectories between high-performance Paralympic (PCS) and Olympic (OCS) canoe sprint. In this study, we compared the developmental trajectories of 200-meter kayak performances among PCS and OCS athletes. In total, we analyzed 628 race results obtained from public online databases, for nine competitions between 2015 and 2023. Race times were reduced over the years except in specific sports classes (KL3-M, K1-M, and K1-F; KL: Kayak Level, M: male, F: female), with a poor positive correlation (r = 0.17 to 0.33) between time and the years. For the remaining sports classes, these correlations ranged from poor to fair (r = -0.58 to -0.13). OCS K1 athletes outperformed their Paralympic counterparts. Among Paralympic classes, KL1 had slower times than KL2 and KL3 (p ≤ .05), with KL2 times significantly lower than KL3 in the female category. OCS athletes exhibited less variability in race times compared to PCS athletes. In the male category, there were no significant differences in the coefficients of variation (CV) and amplitude of race times between sport classes, except for KL1-M, which had a larger CV than K1 (p ≤ .05). In the female category, the CV and amplitude of race times were significantly higher in KL1-F compared to KL3-F and K1-F. OCS times remained stable from 2015, with KL3-M following a similar trend. PCS displayed greater race time variability, particularly in higher impairment classes, notably KL1. This underscores the existence of distinct developmental stages within the canoe sprint modality, particularly emphasizing the early developmental phase of KL1. It also provides valuable insights for coaches and sports selection, especially concerning athletes with more severe impairments, including those in Rehabilitation Centers and during athlete recruitment.

Alterations in performance and discriminating power of the death/suicide implicit association test across the lifespan

The Death/Suicide Implicit Association Test (d/s-IAT) has differentiated individuals with prior and prospective suicide attempts in previous studies, however, age effects on test results remains to be explored. A three-site study compared performance on the d/s-IAT among participants aged 16–80 years with depression and prior suicide attempt (n = 82), with depression and no attempts (n = 80), and healthy controls (n = 86). Outcome measures included the standard difference (D) score, median reaction times, and error rates. Higher D scores represent a stronger association between death/suicide and self, while lower scores represent a stronger association between life and self. The D scores differed significantly among groups overall. Participants with depression exhibited higher scores compared to healthy controls, but there was no difference between participants with and without prior suicide attempts(F[2,242]=8.76, p<.001). Response times for participants with prior attempts differed significantly from other groups, with no significant differences in error rates. The D score was significantly affected by age (β =-0.007, t = 3.65, p<.001), with slowing of response times in older ages. Results suggest reaction time d/s-IAT D scores may not distinguish implicit thinking about suicide as response times slow with age, but slowed response times may be sensitive to suicide risk potentially indicating basic information processing deficits.

Imaging faults and fractures with the difference of fast and slow shear-wave splitting reflectivity, Δγ(S): 3D/9C survey in Midland Basin, West Texas, and 3D/3C survey in Washakie Basin, Wyoming

One of the most important applications of shear-wave (S-wave) seismic exploration has been in reservoir fracture characterization. While many advancements have been made over the past 30 years to compute and correct for the long-wavelength kinematics of S-wave splitting (SWS) (fast S-wave polarization directions and slow S-wave time delays), practically no progress has been made in imaging the short-wavelength reflectivity of fractures directly with Δγ(S). This property is the contrast in the SWS anisotropy parameter, γ(S), and represents the reflection amplitude at vertical incidence for changes in fracture density and orientation across an interface. In this article, we examine the Lupin nine-component survey in Midland Basin, Texas, for the technical reliability of imaging fractures in depth with converted P to S waves (PS waves) guided by pure-mode horizontal shear waves and vertical shear waves. Final Δγ(S) amplitude maps for each mode show sensitivity to fractures, faults, and the maximum horizontal stress direction. These maps are computed from the difference between fast and slow S-wave stacks (after SWS analysis and correction) and P-wave amplitude variation with offset gradient stacks. The S-wave difference maps identify an east–west lineament, possibly a strike-slip fault or fracture corridor, that is not observed by P-wave depth slices. Pure-mode S waves and PS waves are orders of magnitude more sensitive to Δγ(S) than P waves. We also review the development of Δγ(S) and find that it has been relatively unexploited by the exploration industry. In addition, we demonstrate that Δγ(S) can be obtained directly from the objective function of the transverse energy to correct for SWS, and show a four-component Alford rotation example from a previous PS-wave survey in the Washakie Basin, Wyoming.

Structure Optimization and Data Processing Method of Electronic Nose Bionic Chamber for Detecting Ammonia Emissions from Livestock Excrement Fermentation.

In areas where livestock are bred, there is a demand for accurate, real-time, and stable monitoring of ammonia concentration in the breeding environment. However, existing electronic nose systems have slow response times and limited detection accuracy. In this study, we introduce a novel solution: the bionic chamber construction of the electronic nose is optimized, and the sensor response data in the chamber are analyzed using an intelligent algorithm. We analyze the structure of the biomimetic chamber and the surface airflow of the sensor array to determine the sensing units of the system. The system employs an electronic nose to detect ammonia and ethanol gases in a circulating airflow within a closed box. The captured signals are processed, followed by the application of classification and regression models for data prediction. Our results suggest that the system, leveraging the biomimetic chamber, offers rapid gas detection response times. A high classification prediction accuracy, with a determination coefficient R2 value of 0.99 for single-output regression and over 0.98 for multi-output regression predictions, is achieved by incorporating a backpropagation (BP) neural network algorithm. These outcomes demonstrate the effectiveness of the electronic nose, based on an optimized bionic chamber combined with a BP neural network algorithm, in accurately detecting ammonia emitted during livestock excreta fermentation, satisfying the ammonia detection requirements of breeding farms.

Evaluation of Three Cytomegalovirus IgG Lateral Flow Assays for Rapid Determination of CMV Serostatus.

Cytomegalovirus (CMV) serostatus is a major determinant of CMV infection, disease risk, and transplant outcomes. Current clinical serology assays are limited by relatively slow turnaround time, design for batched testing, need for trained personnel, and/or specialized equipment. Rapid diagnostic assays in development have a role in emerging settings, such as critically ill patients, but have not been systematically evaluated. We assessed the performance of 3 rapid lateral flow assays (LFAs) for the detection of CMV immunoglobulin (Ig)G antibodies compared with a reference commercially available CMV IgG enzyme-linked immunosorbent assay in residual serum samples from 200 consecutive adults who underwent clinical CMV serology testing. Samples with discrepant results between the LFA and reference assay were tested by a second reference assay. A subset of serum samples was assessed for interoperator variability. Operating characteristics of the QooLabs LFA were separately assessed in plasma samples. The sensitivity and specificity of the individual LFA assays using serum varied significantly: 86%/83%, 99/93%, and 57/97%, for Healgen, QNow automated reader, and nanoComposix, respectively, compared with the reference assay. Results for the QNow assay were comparable between automated and manual reads. Among a subset of 10 serum samples assessed by 5 individual operators, 44 of 50 (88%) results were concordant. Among 50 plasma samples assessed by the QooLabs LFA, the sensitivity and specificity were 72% and 96%. The ease of performance, rapid turnaround time, and good operating characteristics provide the rationale for further evaluation of the Qoolabs QNow LFA in specialized settings where rapid assessment of CMV serostatus would be advantageous.

Development and validation of a practical solution for detecting motion artefacts in the EOS X-ray system

The EOS™2D/3D system is a low-dose, 3D imaging system that utilizes two perpendicular X-ray beams to create simultaneous frontal and lateral images of the body. This is a useful modality to assess spinal pathologies. However, due to the slow imaging acquisition time up to 25 s, motion artifacts (MA) frequently occur. These artifacts may not be distinguishable from pathological findings, such as scoliosis, and may impair the diagnostic process. The aim of this study was to design a method to detect MA in EOS X-ray. We retrospectively analyzed EOS imaging from 40 patients wearing a radiopaque reference device during imaging. We drew a straight vertical line along the reference device. We measured deviations from it to quantify MA, presenting these findings through descriptive statistics. For a subset of patients with high MA, acquisitions were repeated after giving specific instructions to stand still. For these patients, we compared MA between the two acquisitions. In our study, a substantial proportion of patients exhibited MA ≥ 1 mm, with 80% in frontal projections and 87.9% in lateral projections. In the subjects who received a second acquisition, MA was significantly lower in the second images. Our method allows for a precise detection of MA on EOS images through a simple, yet reliable solution. Our method may improve the reliability of spine measurements, and reduce the risk of wrong diagnosis due to low imaging quality.

Non-contact humidity monitoring: Boosting the performance of all-printed humidity sensor using PDDA-modified Ti3C2Tx nanoribbons

Non-contact humidity monitoring can provide us with rich information about our bodies in a non-invasive way. However, this concept is hindered by the low sensitivity and slow response time of conventional humidity sensors. Herein, we employed two strategies, structural design and surface modification of MXene materials, to improve the sensitivity of MXene-based humidity sensors. A 3D porous structure was formed by the alkalinization treatment MXene, which facilitated rapid diffusion of water molecules along interlayer nanochannels and fast electron transport. Furthermore, the charged positively poly (diallyldimethylammonium chloride) (PDDA) was adsorbed onto the surface of the 3D skeleton through self-assembly to prepare a novel composite material KPMX. The loaded PDDA enhanced the interaction between MXene and water molecules, reducing the oxidation sensitivity of MXene. Additionally, the material was further formulated as inks with suitable viscosity and successfully used to produce a paper-based flexible humidity sensor through screen printing. Consequently, the KPMX sensor exhibited impressive potential in humidity sensing with high sensitivity (48813 %), rapid response/recovery time (8.794/2.656 s), and excellent stability. This work provided a practical strategy for non-contact humidity monitoring, including detecting the proximity of fingertips and changes in humidity in breathing patterns.

Analysis of a Delayed Multiscale AIDS/HIV-1 Model Coupling Between-Host and Within-Host Dynamics

Taking into account the effects of the immune response and delay, and complexity on HIV-1 transmission, a multiscale AIDS/HIV-1 model is formulated in this paper. The multiscale model is described by a within-host fast time model with intracellular delay and immune delay, and a between-host slow time model with latency delay. The dynamics of the fast time model is analyzed, and includes the stability of equilibria and properties of Hopf bifurcation. Further, for the coupled slow time model without an immune response, the basic reproduction number R0h is defined, which determines whether the model may have zero, one, or two positive equilibria under different conditions. This implies that the slow time model demonstrates more complex dynamic behaviors, including saddle-node bifurcation, backward bifurcation, and Hopf bifurcation. For the other case, that is, the coupled slow time model with an immune response, the threshold dynamics, based on the basic reproduction number R˜0h, is rigorously investigated. More specifically, if R˜0h&lt;1, the disease-free equilibrium is globally asymptotically stable; if R˜0h&gt;1, the model exhibits a unique endemic equilibrium that is globally asymptotically stable. With regard to the coupled slow time model with an immune response and stable periodic solution, the basic reproduction number R0 is derived, which serves as a threshold value determining whether the disease will die out or lead to periodic oscillations in its prevalence. The research results suggest that the disease is more easily controlled when hosts have an extensive immune response and the time required for new immune particles to emerge in response to antigenic stimulation is within a certain range. Finally, numerical simulations are presented to validate the main results and provide some recommendations for controlling the spread of HIV-1.

Smooth-surface octahedral Zn2SnO4 sensitized by carbon quantum dot for enhanced triethylamine detection

In this study, the combination of octahedral Zn2SnO4 with the carbon quantum dots (CQDs) is pioneered for the efficient detection of triethylamine. CQDs-modified Zn2SnO4 materials were synthesized to perform rapid detection of trace triethylamine present in air. In the gas test, the optimal composite's response value to triethylamine is 600% higher than the value of the original Zn2SnO4 to triethylamine, and the tendency of selective to triethylamine is more than ten times than other kinds of gases and possesses a short response/recovery times of 18 s/29 s. The exceptional properties of the composite are attributed to the superb electron transport capacity brought by the modification of 5 nm carbon quantum dots. The novel material will solve the issues of slow reaction time and low response of previous materials in detecting triethylamine.

Open-Loop Centering of a Point Mass on a Horizontally Vibrating Frictional Table

Abstract In this paper, we study a particle sliding on a horizontally vibrating frictional table. This dynamical system has applications in parts manipulation within robotics and manufacturing. We first show numerically that, upon vibrating the table in a specific open-loop way, the particle moves to a target location under Coulomb friction alone. We then turn to analytical treatment of the system. The governing equations have strong nonlinearities due to the friction. We apply the method of multiple scales (MMS) near a 1:2 resonance in two frequencies relevant to the forcing. Application of the MMS requires some difficult integrals, for which we develop asymptotic approximations. The MMS slow flow has logarithmic nonlinearities, is valid near the target location on the table, and is easy to integrate numerically since it retains parametric excitation only in slow time. The slow flow matches very well with full numerical solutions. This problem has a practical motivation, novel elements in the application of the MMS, a satisfactory slow flow, and potential for further analytical simplification.

Verification of a method using magnetic bead enrichment and nucleic acid extraction to improve the molecular detection of bacterial contamination in blood components.

Bacterial contamination of blood products poses a significant risk in transfusion medicine. Platelets are particularly vulnerable to bacterial growth because they must be stored at room temperature with constant agitation for >5 days. The limitations of bacterial detection using conventional methods, such as blood cultures and lateral flow assays, include the long detection times, low sensitivity, and the requirement for substantial volumes of blood components. To address these limitations, we assessed the performance of a bacterial enrichment technique using antibiotic-conjugated magnetic nanobeads (AcMNBs) and real-time PCR for the detection of bacterial contamination in plasma. AcMNBs successfully captured >80% of four bacterial strains, including Staphylococcus aureus, Bacillus cereus, Escherichia coli, and Klebsiella pneumoniae, in both plasma and phosphate-buffered saline. After 24-h incubation with bacterial enrichment, S. aureus and B. cereus were each detected at 101 CFU/mL in all trials (5/5), E. coli at 101 CFU/mL in 1/5 trials, and K. pneumoniae at 10² CFU/mL in 4/5 trials. Additionally, without incubation, the improvement was also achieved in samples with bacterial enrichment, S. aureus at 10² CFU/mL and B. cereus at 101 CFU/mL in 1/5 trials each, E. coli at 10³ CFU/mL in 3/5 trials, and K. pneumoniae at 10¹ CFU/mL in 2/5 trials. Overall, the findings from this study strongly support the superiority of bacterial enrichment in detecting low-level bacterial contamination in plasma when employing AcMNBs and PCR.IMPORTANCEThe study presents a breakthrough approach to detect bacterial contamination in plasma, a critical concern in transfusion medicine. Traditional methods, such as blood cultures and lateral flow assays, are hampered by slow detection times, low sensitivity, and the need for large blood sample volumes. Our research introduces a novel technique using antibiotic-conjugated magnetic nanobeads combined with real-time PCR, enhancing the detection of bacteria in blood products, especially platelets. This method has shown exceptional efficiency in identifying even low levels of four different species of bacteria in plasma. The ability to detect bacterial contamination rapidly and accurately is vital for ensuring the safety of blood transfusions and can significantly reduce the risk of infections transmitted through blood products. This advancement is a pivotal step in improving patient outcomes and elevating the standards of care in transfusion medicine.

Effects of acute cannabis inhalation on reaction time, decision-making, and memory using a tablet-based application

BackgroundAcute cannabis use has been demonstrated to slow reaction time and affect decision-making and short-term memory. These effects may have utility in identifying impairment associated with recent use. However, these effects have not been widely investigated among individuals with a pattern of daily use, who may have acquired tolerance. The purpose of this study was to examine the impact of tolerance to cannabis on the acute effects as measured by reaction time, decision-making (gap acceptance), and short-term memory.MethodsParticipants (ages 25–45) completed a tablet-based (iPad) test battery before and approximately 60 min after smoking cannabis flower. The change in performance from before to after cannabis use was compared across three groups of cannabis users: (1) occasional use (n = 23); (2) daily use (n = 31); or (3) no current use (n = 32). Participants in the occasional and daily use group self-administered ad libitum, by smoking or vaping, self-supplied cannabis flower with a high concentration of total THC (15–30%).ResultsThe occasional use group exhibited decrements in reaction time (slowed) and short-term memory (replicated fewer shapes) from before to after cannabis use, as compared to the no-use group. In the gap acceptance task, daily use participants took more time to complete the task post-smoking cannabis as compared to those with no use or occasional use; however, the level of accuracy did not significantly change.ConclusionsThe findings are consistent with acquired tolerance to certain acute psychomotor effects with daily cannabis use. The finding from the gap acceptance task which showed a decline in speed but not accuracy may indicate a prioritization of accuracy over response time. Cognitive and psychomotor assessments may have utility for identifying impairment associated with recent cannabis use.