Individual differences in teleporting through virtual environments.

Virtual reality (VR) allows users to walk to explore the virtual environment (VE), but this capability is constrained by real obstacles. Teleporting interfaces overcome this constraint by allowing users to select a position, and sometimes orientation, in the VE before being instantly transported without self-motion cues. This study investigated whether individual differences in navigation performance when teleporting correspond to characteristics of the individual, including spatial ability. Participants performed triangle completion (traverse two outbound path legs, then point to the path origin) within VEs differing in visual landmarks. Locomotion was accomplished using three interfaces: walking, partially concordant teleporting (teleport to change position, rotate the body to change orientation), and discordant teleporting (teleport to change position and orientation). A latent profile analysis identified three profiles of individuals: those who performed well overall and improved with landmarks, those who performed poorly without landmarks but improved when available, and those who performed poorly even with landmarks. Characteristics of individuals differed across profiles, including gender, self-reported spatial ability, mental rotation, and perspective-taking; but only perspective-taking significantly distinguished all three profiles. This work elucidates spatial cognitive correlates of navigation and provides a framework for identifying susceptibility to disorientation in VR. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

A new paradigm in management of frequent attenders to emergency departments with severe alcohol use disorder-A pilot study for assertive community treatment in Singapore.

Introduction: A majority of frequent users of emergency medical services in Singapore present with alcohol-related problems. These patients are known to engage poorly with traditional addiction services and frequently attend Emergency Departments (EDs) instead, resulting in high healthcare burden. Assertive Community Treatment (ACT) is an alternative intervention to traditional addiction management. ACT involves community visits with focus on holistic care and harm-reduction. Materials and methods: We conducted a prospective before-and-after cohort study at the major tertiary center for addiction disorders in Singapore. The main objective was to evaluate effectiveness of ACT in reducing alcohol-related attendances at EDs nationwide. Socio-demographics, alcohol-related ED attendances, and the Christo Inventory for Substance-misuse Services (CISS) scores were collected for the patients recruited from April 2018 to March 2019. Descriptive analyses and the Wilcoxon Signed-Rank Test were performed. Results: All 14 patients were male with a mean age of 55 years. There was a significant 45.3% reduction in average alcohol-related ED attendances from 6.8 (range 3-22, median 5.5) in the pre-intervention 6-month period, to 3.7 (range 0-28, median 1.5) in the post-intervention 6-month period (Z = -2.244, p = 0.025). CISS scores showed significant improvement from a pre-intervention median of 13.5 (range 9-16) to a post-intervention median of 6.5 (range 1-10, p = 0.001), corresponding to reduction in alcohol-related problem severity. Conclusion: This pilot study suggests that ACT can be effective in reducing alcohol-related ED attendances and alcohol-related problem severity in patients with AUD who frequently attend ED. A multicenter, prospective study using ACT for such patients across four hospitals in Singapore is currently underway.

Classical Hodgkin Lymphoma: Clinicopathologic Features, Prognostic Factors, and Outcomes From a 28-Year Single Institutional Experience.

INTRODUCTION: Classical Hodgkin lymphoma (cHL) is a curable malignancy, with a complete remission rate of approximately 90%. However, relapse remains a significant cause of mortality. Prognostic factors are useful in guiding therapy. This is a large, single-institution study defining the clinicopathologic features, prognostic factors, and treatment outcomes of patients with cHL. PATIENTS AND METHODS: We reviewed 727 patients with cHL treated at H. Lee Moffitt Cancer Center and Research Institute from 1990 to 2017. Data on demographics, laboratory studies, and disease statuses were collected from the institutional database and electronic medical records. Statistical analyses, overall survival (OS), progression-free survival (PFS), and multivariate analyses were performed. RESULTS: The median age was 35 years. Fifty-four percent of patients were men; 45.6% had advanced stage disease; 82% were treated with ABVD (doxorubicin hydrochloride [adriamycin], bleomycin sulfate, vincristine, and dacarbazine) as frontline therapy; and 70% achieved complete response. The median PFS after first-line treatment was 16.8 years. The median OS of patients with early stage and advanced stage cHL was 19 and 12.9 years, respectively. Poor prognostic factors for OS included older age, advanced stage disease, presence of B symptoms, and a higher International Prognostic Score. CONCLUSION: Despite high cure rates, cHL accounted for the cause of death in 47% of patients who died during follow-up. Prognostic factors, such as age, stage at diagnosis, International Prognostic Score, and B symptoms, are helpful to guide treatment. Outcomes observed in this study are comparable with those reported in previously published studies.

A microfluidic chip-compatible bioassay based on single-molecule detection with high sensitivity and multiplexing.

Many applications in pharmaceutical development, clinical diagnostics, and biological research demand rapid detection of multiple analytes (multiplexed detection) in a minimal volume. This need has led to the development of several novel array-based sensors. The most successful of these so far have been suspension arrays based on polystyrene beads. However, the 5 microm beads used for these assays are incompatible with most microfluidic chip technologies, mostly due to clogging problems. The challenge, then, is to design a detection particle that has high information content (for multiplexed detection), is compatible with miniaturization, and can be manufactured easily at low cost. DNA is a solid molecular wire that is easily produced and manipulated, which makes it a useful material for nanoparticles. DNA molecules are very information-rich, readily deformable, and easily propagated. We exploit these attributes in a suspension array sensor built from specialized recombinant DNA, Digital DNA, that carries both specific analyte-recognition units, and a geometrically encoded identification pattern. Here we show that this sensor combines high multiplexing with high sensitivity, is biocompatible, and has sufficiently small particle size to be used within microfluidic chips that are only 1 microm deep. We expect this technology will be the foundation of a broadly applicable technique to identify and quantitate proteins, nucleic acids, viruses, and toxins simultaneously in a minimal volume.

Teleporting through virtual environments: Effects of path scale and environment scale on spatial updating.

Virtual reality systems typically allow users to physically walk and turn, but virtual environments (VEs) often exceed the available walking space. Teleporting has become a common user interface, whereby the user aims a laser pointer to indicate the desired location, and sometimes orientation, in the VE before being transported without self-motion cues. This study evaluated the influence of rotational self-motion cues on spatial updating performance when teleporting, and whether the importance of rotational cues varies across movement scale and environment scale. Participants performed a triangle completion task by teleporting along two outbound path legs before pointing to the unmarked path origin. Rotational self-motion reduced overall errors across all levels of movement scale and environment scale, though it also introduced a slight bias toward under-rotation. The importance of rotational self-motion was exaggerated when navigating large triangles and when the surrounding environment was large. Navigating a large triangle within a small VE brought participants closer to surrounding landmarks and boundaries, which led to greater reliance on piloting (landmark-based navigation) and therefore reduced-but did not eliminate-the impact of rotational self-motion cues. These results indicate that rotational self-motion cues are important when teleporting, and that navigation can be improved by enabling piloting.

Spatial cognitive implications of teleporting through virtual environments.

Teleporting is a popular interface to allow virtual reality users to explore environments that are larger than the available walking space. When teleporting, the user positions a marker in the virtual environment and is instantly transported without any self-motion cues. Five experiments were designed to evaluate the spatial cognitive consequences of teleporting and to identify environmental cues that could mitigate those costs. Participants performed a triangle completion task by traversing 2 outbound path legs before pointing to the unmarked path origin. Locomotion was accomplished via walking or 2 common implementations of the teleporting interface distinguished by the concordance between movement of the body and movement through the virtual environment. In the partially concordant teleporting interface, participants teleported to translate (change position) but turned the body to rotate. In the discordant teleporting interface, participants teleported to translate and rotate. Across all 5 experiments, discordant teleporting produced larger errors than partially concordant teleporting which produced larger errors than walking, reflecting the importance of translational and rotational self-motion cues. Furthermore, geometric boundaries (room walls or a fence) were necessary to mitigate the spatial cognitive costs associated with teleporting, and landmarks were helpful only in the context of a geometric boundary. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Whole-genome shotgun optical mapping of Rhodospirillum rubrum.

Rhodospirillum rubrum is a phototrophic purple nonsulfur bacterium known for its unique and well-studied nitrogen fixation and carbon monoxide oxidation systems and as a source of hydrogen and biodegradable plastic production. To better understand this organism and to facilitate assembly of its sequence, three whole-genome restriction endonuclease maps (XbaI, NheI, and HindIII) of R. rubrum strain ATCC 11170 were created by optical mapping. Optical mapping is a system for creating whole-genome ordered restriction endonuclease maps from randomly sheared genomic DNA molecules extracted from cells. During the sequence finishing process, all three optical maps confirmed a putative error in sequence assembly, while the HindIII map acted as a scaffold for high-resolution alignment with sequence contigs spanning the whole genome. In addition to highlighting optical mapping's role in the assembly and confirmation of genome sequence, this work underscores the unique niche in resolution occupied by the optical mapping system. With a resolution ranging from 6.5 kb (previously published) to 45 kb (reported here), optical mapping advances a "molecular cytogenetics" approach to solving problems in genomic analysis.

A microfluidic system for large DNA molecule arrays.

Single molecule approaches offer the promise of large, exquisitely miniature ensembles for the generation of equally large data sets. Although microfluidic devices have previously been designed to manipulate single DNA molecules, many of the functionalities they embody are not applicable to very large DNA molecules, normally extracted from cells. Importantly, such microfluidic devices must work within an integrated system to enable high-throughput biological or biochemical analysis-a key measure of any device aimed at the chemical/biological interface and required if large data sets are to be created for subsequent analysis. The challenge here was to design an integrated microfluidic device to control the deposition or elongation of large DNA molecules (up to millimeters in length), which would serve as a general platform for biological/biochemical analysis to function within an integrated system that included massively parallel data collection and analysis. The approach we took was to use replica molding to construct silastic devices to consistently deposit oriented, elongated DNA molecules onto charged surfaces, creating massive single molecule arrays, which we analyzed for both physical and biochemical insights within an integrated environment that created large data sets. The overall efficacy of this approach was demonstrated by the restriction enzyme mapping and identification of single human genomic DNA molecules.

A whole-genome shotgun optical map of Yersinia pestis strain KIM.

Yersinia pestis is the causative agent of the bubonic, septicemic, and pneumonic plagues (also known as black death) and has been responsible for recurrent devastating pandemics throughout history. To further understand this virulent bacterium and to accelerate an ongoing sequencing project, two whole-genome restriction maps (XhoI and PvuII) of Y. pestis strain KIM were constructed using shotgun optical mapping. This approach constructs ordered restriction maps from randomly sheared individual DNA molecules directly extracted from cells. The two maps served different purposes; the XhoI map facilitated sequence assembly by providing a scaffold for high-resolution alignment, while the PvuII map verified genome sequence assembly. Our results show that such maps facilitated the closure of sequence gaps and, most importantly, provided a purely independent means for sequence validation. Given the recent advancements to the optical mapping system, increased resolution and throughput are enabling such maps to guide sequence assembly at a very early stage of a microbial sequencing project.

An Empirical Examination of the Educational Impact of Text Message-Induced Task Switching in the Classroom: Educational Implications and Strategies to Enhance Learning

Comparando con las generaciones anteriores, la actual generación que ahora cursan estudios universitarios pueden ser denominados generación Internet y generación ?multitarea´, principalmente en lo que se refiere al uso que estos hacen de las herramientas de comunicación electrónicas (Carrier et al., 2009). Además, existen estudios que demuestran que muchos alumnos envían mensajes de texto durante sus clases (Tindell & Bohlander, 2011). Estudios recientes llevados a cabo en laboratorios (Ophir, et al., 2009) han constatado que el efectuar múltiples tareas a la vez perjudica el rendimiento, sobre todo entre los que más tareas llevan a cabo. Además, otras investigaciones experimentales han mostrado que las interrupciones inducidas por la tecnología son especialmente perjudiciales, provocando errores y un rendimiento menor (Monk, et al., 2008). Esta investigación estudió el efecto de enviar y recibir SMS durante una clase magistral. El presente estudio es el primero en abordar de forma experimental el efecto de los mensajes de texto sobre la memoria en el contexto del aula. Los participantes asistieron a una clase de 30 minutos grabada previamente en vídeo. Mientras tanto, se les enviaba a los participantes vía SMS preguntas que requerían respuestas. Los participantes estaban distribuidos entre cuatro aulas y divididos, dentro de cada aula, y de forma aleatoria, en tres grupos: participantes que no recibieron ningún SMS; participantes que recibieron cuatro SMS; y participantes que recibieron ocho SMS. Según el número de mensajes recibidos y enviados ?incluidos los que no fueron enviados por el investigador- se definieron tres grupos de comparación: cero/bajo nivel de interrupciones (entre cero y siete mensajes enviados y recibidos); nivel moderado de interrupciones (de 8 a 15 mensajes); y nivel alto de interrupciones (16 o más). Después de ver la clase grabada, se evaluó mediante una prueba de memoria el efecto de las interrupciones sobre la memoria (AU)

Today´s Net Generation university students multitask more than any prior generation, primarily using electronic communication tools (Carrier et al., 2009). In addition, studies report that many students text during class (Tindell & Bohlander, 2011). This research examines the impact of receiving and sending text messages during a classroom lecture. Recent laboratory research (Ophir, et al., 2009) reported that multitasking impaired performance, particularly among heavy multitaskers. Further, experimental research has shown that "technologically induced" interruptions can be disruptive, causing increased errors and decreased performance (Monk, et al., 2008). This study is the first to experimentally examine the direct impact of text message interruptions on memory recall in a classroom environment. Participants viewed a 30-minute videotaped lecture during which they were interrupted by receiving text messages requiring responses. Participants in four classrooms were randomly assigned to three groups receiving no text messages, four text messages or eight text messages. Based on the actual number of texts received and sent? including those not sent by the experimenter?three comparison groups were defined: No/Low Texting Interruption (zero to 7 text messages sent and received), Moderate Texting Interruption (eight to 15 texts), and High Texting Interruption (16 or more texts). Following the videotaped lecture, a recall test assessed the impact of text message interruptions on memory (AU)