Developing a model to evaluate and improve user experience with hand motions in virtual reality environments.

In video games, the evaluation of the user experience (UX) mainly refers to two main groups of aspects, those that refer to the player that is mainly oriented to make the player feel good while playing and those that refer to the video game that is oriented to make the video game easy to understand and play. The aspects considered that are related to the player are engagement, enjoyment, and flow; the aspects related to video game, usability, and dependability. Virtual reality environments today have changed the paradigm in various fields of application, such as health, education, entertainment, among others. Therefore, it is important to observe the effects of handedness with hand movements in virtual reality environments. This work proposes a model to evaluate and improve the user experience considering player and video game aspects, taking into account handedness with hand movements in virtual reality environments. Player and video game aspects can be added to evaluations of the effect of handedness, especially in virtual reality environments, in order to know the user's behavior in terms of skill, performance, and accuracy, among other features by using a particular hand to perform specific tasks. Next, a case study is presented with two groups of users using a virtual reality environment to perform several user tasks considering the dominant and non-dominant hand. By evaluating the user tasks it is possible to know the levels of engagement, enjoyment, motivation, and usability in a virtual reality environment. Finally, an analysis of results is presented in which several improvements of UX are presented.

Heterobimetallic Catalysts for the Thermal Decomposition of Ammonium Perchlorate: Efficient Burning Rate Catalysts for Solid Rocket Motors and Missiles.

We show the synthesis and characterization of four heterobimetallic compounds derived from s-indacene of general formula [{(CO)3Mn}-s-Ic-{MCp*}]q with M = Fe, Co, Ni, and Ru; q = 0, 1+. The complexes reported here were characterized by 1H and 13C NMR, elemental analysis and FT-IR. Additionally, the X-ray crystal structure of [(CO)3Mn-s-Ic-FeCp*] (1) and Mössbauer spectra are reported. The heterobimetallic compounds exhibit higher quasireversible redox potentials compared with ferrocene and catocene under the same reaction conditions. The complexes were tested as catalysts on the thermal decomposition of ammonium perchlorate examined by a differential scanning calorimetry technique to study their catalytic behavior. Compound (1) causes a decrease of ammonium perchlorate's decomposition temperature to 315 °C, consequently increasing the heat release by 138 J·g-1. Conversely, [{(CO)3Mn}-s-Ic'-{CoCp*}] (2) presents a higher heat release (2462 J·g-1), comparable to catocene.

A Lean UX Process Model for Virtual Reality Environments Considering ADHD in Pupils at Elementary School in COVID-19 Contingency.

Today, the world is experiencing the COVID-19 health contingency, which prevents people from being exposed to one another and restricts physical contact. Under this context, the use of technology has become an essential tool to face the challenges of daily life, and virtual reality can be an alternative in the development of solutions that effectively support the acquisition of learning skills and knowledge transmission through the execution of tasks designed by multi-disciplinary groups. In addition, it can encourage the user to continue with the acquisition of learning skills in a friendly and fun way in a health and education context. This work proposes the use of virtual reality environments as an alternative to support the learning process in children with special educational needs such as Attention Deficit Hyperactivity Disorder (ADHD) and other associated disorders that occur in basic education. These proposed reality environments are designed under the Lean UX process model and their contents are designed according to expert therapeutic guidelines. As a result of this proposal, a case study is presented in which the user experience is evaluated through the use of an interactive environment to support the special educational needs of elementary school children attending an educational institution in Mexico.

A Learning Analytics Framework to Analyze Corporal Postures in Students Presentations.

Communicating in social and public environments are considered professional skills that can strongly influence career development. Therefore, it is important to proper train and evaluate students in this kind of abilities so that they can better interact in their professional relationships, during the resolution of problems, negotiations and conflict management. This is a complex problem as it involves corporal analysis and the assessment of aspects that until recently were almost impossible to quantitatively measure. Nowadays, a number of new technologies and sensors have being developed for the capture of different kinds of contextual and personal information, but these technologies were not yet fully integrated inside learning settings. In this context, this paper presents a framework to facilitate the analysis and detection of patterns of students in oral presentations. Four steps are proposed for the given framework: Data collection, Statistical Analysis, Clustering, and Sequential Pattern Mining. Data Collection step is responsible for the collection of students interactions during presentations and the arrangement of data for further analysis. Statistical Analysis provides a general understanding of the data collected by showing the differences and similarities of the presentations along the semester. The Clustering stage segments students into groups according to well-defined attributes helping to observe different corporal patterns of the students. Finally, Sequential Pattern Mining step complements the previous stages allowing the identification of sequential patterns of postures in the different groups. The framework was tested in a case study with data collected from 222 freshman students of Computer Engineering (CE) course at three different times during two different years. The analysis made it possible to segment the presenters into three distinct groups according to their corporal postures. The statistical analysis helped to assess how the postures of the students evolved throughout each year. The sequential pattern mining provided a complementary perspective for data evaluation and helped to observe the most frequent postural sequences of the students. Results show the framework could be used as a guidance to provide students automated feedback throughout their presentations and can serve as background information for future comparisons of students presentations from different undergraduate courses.

High-Resolution Thermal Imaging and Analysis of TIG Weld Pool Phase Transitions.

Tungsten inert gas (TIG) welding is a well-established joining process and offers the user flexibility to weld a large range of materials. Ultra-thin turbine tipping is an important application for TIG welding that is exceptionally challenging due to the wide range of variables needed to accurately control the process: slope times, arc control, travel speed, etc. We offer new insight into weld pool characteristics, utilizing both on- and off-line measurements of weld tracks. High-resolution thermal imaging yields spatially and temporally resolved weld pool phase transitions coupled with post-weld photographs, which gives a novel perspective into the thermal history of a weld. Our imaging system is filtered to measure a 10 nm window at 950 nm and comprises a commercial Sigma lens to produce a near-infrared (NIR) camera. The measured near-infrared radiance is calibrated for temperature over the range of from 800 to 1350 °C.

A Multimodal Real-Time Feedback Platform Based on Spoken Interactions for Remote Active Learning Support.

While technology has helped improve process efficiency in several domains, it still has an outstanding debt to education. In this article, we introduce NAIRA, a Multimodal Learning Analytics platform that provides Real-Time Feedback to foster collaborative learning activities' efficiency. NAIRA provides real-time visualizations for students' verbal interactions when working in groups, allowing teachers to perform precise interventions to ensure learning activities' correct execution. We present a case study with 24 undergraduate subjects performing a remote collaborative learning activity based on the Jigsaw learning technique within the COVID-19 pandemic context. The main goals of the study are (1) to qualitatively describe how the teacher used NAIRA's visualizations to perform interventions and (2) to identify quantitative differences in the number and time between students' spoken interactions among two different stages of the activity, one of them supported by NAIRA's visualizations. The case study showed that NAIRA allowed the teacher to monitor and facilitate the learning activity's supervised stage execution, even in a remote learning context, with students working in separate virtual classrooms with their video cameras off. The quantitative comparison of spoken interactions suggests the existence of differences in the distribution between the monitored and unmonitored stages of the activity, with a more homogeneous speaking time distribution in the NAIRA supported stage.

Introducing Low-Cost Sensors into the Classroom Settings: Improving the Assessment in Agile Practices with Multimodal Learning Analytics.

Currently, the improvement of core skills appears as one of the most significant educational challenges of this century. However, assessing the development of such skills is still a challenge in real classroom environments. In this context, Multimodal Learning Analysis techniques appear as an attractive alternative to complement the development and evaluation of core skills. This article presents an exploratory study that analyzes the collaboration and communication of students in a Software Engineering course, who perform a learning activity simulating Scrum with Lego® bricks. Data from the Scrum process was captured, and multidirectional microphones were used in the retrospective ceremonies. Social network analysis techniques were applied, and a correlational analysis was carried out with all the registered information. The results obtained allowed the detection of important relationships and characteristics of the collaborative and Non-Collaborative groups, with productivity, effort, and predominant personality styles in the groups. From all the above, we can conclude that the Multimodal Learning Analysis techniques offer considerable feasibilities to support the process of skills development in students.

Seven Years of Parrot Conservation in La Moskitia, Honduras.

The population of the Central American scarlet macaw ( Ara macao cyanoptera) and other parrots have and continue to decline throughout the region largely from poaching to supply the illegal wildlife trade. Conservation efforts address this issue through protection efforts, including community patrols and government engagement, as well as nest monitoring, rescue and release operations, capacity building, and education and consciousness raising programs, all of which rely on long-lasting relationships and commitment. Using these principles, in 2010, a coalition of people came together, including the authors, to build a conservation program against overwhelming odds and with surprising success.

Multidisciplinary production of interactive environments to support occupational therapies.

This work focuses on proposing a multidisciplinary production of interactive environments as a technological support for rehabilitation of people with physical disabilities attending occupational therapy. Nowadays, some technologies and methods are used to develop software in order to assist the people who suffer some kind of physical disability but the physical therapies aren't limited to only one technique of rehabilitation. Current work promotes establish a multidisciplinary team such as therapists and technologists, they can collaborate for the production of interactive environments according the evolution of every patient's rehabilitation. The performance of current proposal is presented throughout a related work and a case study with several usability evaluations.

Sustained release of calcium hydroxide from poly(DL-lactide-co-glycolide) acid microspheres for apexification.

Calcium hydroxide (CH) loaded poly(DL-lactide-co-glycolide) acid (PLGA) microspheres (MS) might be used for apexification requiring a sustained release of Ca(2+). The aim of this study was to formulate and characterize CH-PLGA-MS. The CH-loaded MS were prepared by either oil-in-water (O/W) or water-in-oil/in-water (W/O/W) emulsion solvent evaporation technique. MS produced by the O/W technique exhibited a larger diameter (18.63 ± 7.23 µm) than the MS produced by the W/O/W technique (15.25 ± 7.37 µm) (Mann-Whitney U test P < 0.001). The CH encapsulation efficiency (E e) and Ca(2+) release were calculated from data obtained by absorption techniques. Ca(2+) release profile was evaluated for 30 days. To know the E e, the CH-loaded MS were dissolved in 1 M NaOH to release all its content and a Ca(2+) colorimetric marker was added to this solution. The reagent marked the Ca(2+) in blue color, which was then measured by a UV-Vis system (650 nm). The percentage of E e was calculated on the basis of the theoretical loading. The E e of the O/W-produced MS was higher (24 %) than the corresponding percentage of the W/O/W-produced MS (11 %). O/W- and W/O/W-produced MS released slower and lower Ca(2+) than a control CH paste with polyethylene glycol 400 (Kruskal-Wallis test). O/W-produced MS released higher Ca(2+) than W/O/W-produced MS (statistically significant differences; P < 0.05). In conclusion, the CH-PLGA-MS were successfully formulated; the technique of formulation influenced the size, encapsulation efficiency and release profile. The MS were better sustained release system than the CH paste.

Sensory Neuropeptides and Endogenous Opioids Expression in Human Dental Pulp with Asymptomatic Inflammation: In Vivo Study.

PURPOSE: This study quantified the expression of substance P (SP), calcitonin gene-related peptide (CGRP), ß-endorphins (ß-End), and methionine-enkephalin (Met-Enk) in human dental pulp following orthodontic intrusion. METHODS: Eight patients were selected according to preestablished inclusion criteria. From each patient, two premolars (indicated for extraction due to orthodontic reasons) were randomly assigned to two different groups: the asymptomatic inflammation group (EXPg), which would undergo controlled intrusive force for seven days, and the control group (CTRg), which was used to determine the basal levels of each substance. Once extracted, dental pulp tissue was prepared to determine the expression levels of both neuropeptides and endogenous opioids by radioimmunoassay (RIA). RESULTS: All samples from the CTRg exhibited basal levels of both neuropeptides and endogenous opioids. By day seven, all patients were asymptomatic, even when all orthodontic-intrusive devices were still active. In the EXPg, the SP and CGRP exhibited statistically significant different levels. Although none of the endogenous opioids showed statistically significant differences, they all expressed increasing trends in the EXPg. CONCLUSIONS: SP and CGRP were identified in dental pulp after seven days of controlled orthodontic intrusion movement, even in the absence of pain.

Surface Modification of Nerve Guide Conduits with ECM Coatings and Investigating Their Impact on Schwann Cell Response.

In this study, layer-by-layer coatings composed of heparin and collagen are proposed as an extracellular mimetic environment on nerve guide conduits (NGC) to modulate the behavior of Schwann cells (hSCs). The authors evaluated the stability, degradation over time, and bioactivity of six bilayers of heparin/collagen layer-by-layer coatings, denoted as (HEP/COL)6. The stability study reveals that (HEP/COL)6 is stable after incubating the coatings in cell media for up to 21 days. The impact of (HEP/COL)6 on hSCs viability, protein expression, and migration is evaluated. These assays show that hSCs cultured in (HEP/COL)6 have enhanced protein expression and migration. This condition increases the expression of neurotrophic and immunomodulatory factors up to 1.5-fold compared to controls, and hSCs migrated 1.34 times faster than in the uncoated surfaces. Finally, (HEP/COL)6 is also applied to a commercial collagen-based NGC, NeuraGen, and hSC viability and adhesion are studied after 6 days of culture. The morphology of NeuraGen is not altered by the presence of (HEP/COL)6 and a nearly 170% increase of the cell viability is observed in the condition where NeuraGen is used with (HEP/COL)6. Additionally, cell adhesion on the coated samples is successfully demonstrated. This work demonstrates the reparative enhancing potential of extracellular mimetic coatings.

Aesthetic Rib Cage Remodeling with Osteosynthesis: Body Structural High-Definition Reshaping (RIBOSS).

BACKGROUND: Rib cage remodeling has shown promising aesthetic results as a new technique for body contouring yet risks and complications associated with the procedure have not been well established. The aim of our study is to assess safety, efficacy and patient satisfaction rate associated with a new surgical technique for waistline definition. METHODS: We looked into our records for patients who underwent waist narrowing through a new rib remodeling procedure with osteosynthesis of the 11th and 12th ribs; from October 2022 to June 2023. Follow up was carried out at 1 and 3 months after surgery. Outcomes were evaluated based on waist and hip measures, body images, pain and a patient satisfaction survey. RESULTS: A total of 27 consecutive patients were included in the analysis. Our technique resulted in a significant reduction in waist circumference, as evidenced by a decrease of 12.1 cm and 13.0 cm at the first and third month respectively (p<0.005). A reduction of hip circumference of 6.2 cm and 8.7 cm was also reported. A high patient satisfaction rate was reported. Postoperative complications included only one case of wound dehiscence and one case of mild pain. Pain levels were also reduced, with a mean pain score of 2.4 at week 1 and 0.26 at month 1. CONCLUSION: Rib osteotomy with osteosynthesis emerges as an innovative, safe, and reliable approach for waist narrowing. Our results suggest that this technique can be applied to a wide variety of patients and presents might entail significant advantages compared to those from other techniques. TYPE OF STUDY: Retrospective cohort. Level of Evidence: III.

Functional outcomes of children with index pollicizations for thumb deficiency.

PURPOSE: To gain a comprehensive perspective on outcomes by performing an array of tests on patients who had undergone index pollicization for isolated thumb aplasia or severe hypoplasia in the absence of clinical radial dysplasia; this led us to create a graphical snapshot for future comparison. Another purpose was to compare the function of the contralateral hand and to compare parent and patient perspectives. METHODS: We evaluated 22 hands (18 patients) by grip as well as lateral and tripod pinch strength tests; the pegboard Functional Dexterity Test (FDT); the Jebsen Hand Function Test (JHFT); and a parent/patient questionnaire. We compared operated hands with both contralateral nonoperated hands and nondominant hands in published normal data. We also compared contralateral nonoperated hands with dominant hands in published normal data, and FDT results and JHFT outcomes in children greater than 6 years old with published normal data. We evaluated questionnaire results. RESULTS: Mean grip as well as lateral and tripod pinch strength in operated hands were 3.4, 1.2, and 1.2 kg, and in normal nondominant hands were 11.7, 4.4, and 3.9 kg, respectively. Patients' contralateral nonoperated hands were weaker than normal dominant hands. Mean timed FDT results in operated hands was 127 seconds, compared with 44 seconds in published normal data. In 2 of 5 JHFT subtests administered, no difference existed between operated hands and published normal data. A graphical snapshot took various outcome measures into consideration and showed a global assessment. Mean parent and patient questionnaire scores were 10 and 22, respectively (best = 12; worst = 60). CONCLUSIONS: Comprehensive subjective and objective outcome testing suggested that an optimistic view of function after index pollicization is warranted. A graphical snapshot followed function over time. The contralateral hand fared worse than published normal data. Parent and patient perspectives were favorable. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic III.

4-Hy-droxy-6-methyl-pyridin-2(1H)-one.

In the crystal structure of the title compound, C6H7NO2, N-H⋯O and O-H⋯O hydrogen bonds link the mol-ecules, forming a zigzag array along [001] and a layer structure parallel to the ab plane.

Evaluation of Mono and Bimetallic Ferrocene-Based 1,2,3-Triazolyl Compounds as Burning Rate Catalysts for Solid Rocket Motor.

We reported mono and bimetallic ferrocene-based 1,2,3-triazolyl compounds as potential burning rate catalysts in their neutral and ionic forms. All complexes reported here were characterized using 1H and 13C NMR, elemental analysis, and Mössbauer spectroscopy, which was performed for neutral and oxide compounds. The complexes present quasireversible redox potentials with higher oxidative ability than ferrocene and catocene under the same conditions. The complexes were tested as catalysts on the thermal decomposition of ammonium perchlorate (AP) and examined by a differential scanning calorimetry technique to gain further knowledge about their catalytic behavior. Compound 1 causes a decrease of the high-temperature decomposition (HTD) of AP positively, decreasing the decomposition temperature of AP to 345 °C and consequently increasing the energy release to 1939 J·g-1. We took the residues from the pans after testing from the DSC to elucidate the underlying reaction pathways. We obtained the size of the nanostructures formed after thermal decomposition of AP determined by the TEM technique. The diameter and size distribution of iron oxide nanoparticles formed depend on the alkyl sidechain of the triazolium ring, which induces the formation of nanoparticles with a double diameter and size distribution compared to their neutral analogues, suggesting that the possible intermediate for the mechanism degradation of AP by ferrocene derivatives is nanoscale Fe2O3 or similar oxides.

[Histomorphological changes in newborn rat lung induced by maternal sugar intake]. / Cambios histomorfológicos en pulmón de rata recién nacida inducidos por ingesta materna de azúcar.

INTRODUCTION: Respiratory conditions are the most common reason for admission to the neonatal unit for both term and premature newborns. It is known that nutritional imbalances during pregnancy affect the maturation and functional capacity of organs. OBJECTIVE: to describe the pulmonary histomorpholo- gy of newborn rats due to maternal sugar intake by light microscopy. MATERIAL AND METHOD: Twenty 4-week-old female Wistar rats divided into control and experimental groups with sucrose before and during pregnancy were used. At week 15, the females mated with males overnight. We recorded va lues from the body and lung weight of the newborns. The lungs were stained using Hematoxylin and Eosin, Masson's trichrome, Periodic acid-Schiff, and Verhoeff. RESULTS: Newborns from the experi mental group presented significantly lower body and lung weight (6.980 ± 0.493* g, 0.164 ± 0.022* g; *p < 0,05) compared with controls (7.854 ± 0.497 g, 0.189 ± 0.005 g). The lungs of the experimental group showed structural alterations in the lung parenchyma, as well as changes in glycogen deposits, collagen fibers, and elastin compared with the control group. CONCLUSION: Alterations in newborn lung growth and development are associated with maternal sucrose intake. It is important to re member that interventions on the maternal diet have beneficial effects for both the mother and the newborn.

Comparison between rotary and manual techniques on duration of instrumentation and obturation times in primary teeth.

OBJECTIVE: The aim of this study was to compare the duration of instrumentation and obturation times and quality of root canal filling between rotary and manual instrumentation techniques in primary teeth. STUDY DESIGN: A randomized, controlled clinical trial was performed that included deciduous teeth with pulp necrotic. Forty necrotic teeth were included; 20 were instrumented with a rotary technique (experimental group) and 20 with a manual technique (control group). The time taken for instrumentation and for obturation were recorded in minutes, and the quality of the root canal filling was recorded as optimal, under-filled, or overfilled. RESULTS: The use of the rotary technique diminished the time of instrumentation to 63% and time of obturation to 68%, and it improved the quality of the root canalfilling. CONCLUSION: The use of rotary instruments in the pulpectomy of primary molars represents a promising technique; the time is significantly reduced.

Subcutaneous temporal browlift under local anesthesia: a useful technique for periorbital rejuvenation.

BACKGROUND: Various techniques have been described for periorbital rejuvenation and correction of the ptotic brow, including the coronal brow lift, the endoscopic brow lift, anterior hairline foreheadplasty in the subgaleal, subperiosteal, or subcutaneous planes, and the subcutaneous temporal brow lift. OBJECTIVES: The authors present results from a series of 28 patients treated with subcutaneous temporal brow lift over nearly four years. METHODS: A retrospective chart review was conducted of 28 patients who were treated with subcutaneous temporal brow lift by the senior author (JDF) between July 2003 and January 2007. All patients underwent the same subcutaneous temporal brow lift procedure under local anesthesia in an office-based setting. No combined procedures were performed on any of the patients in this series. RESULTS: Of the 28 patients, 27 were female and one was male; mean age was 54 years. Five patients underwent a unilateral brow lift for asymmetry and 23 patients underwent a bilateral procedure. The mean length of follow-up was 10.8 months. Scarring was minimal and rated as "good" or "excellent" by both patients and surgeon. The effectiveness of the browlift was also rated as "good" or "excellent" by all but one patient. Two patients underwent revision-one for scar revision and the other for a greater degree of lift. There were no incidences of hematoma, infection, numbness, or excessive scarring. CONCLUSIONS: The subcutaneous temporal brow lift is an effective, reproducible, and inexpensive technique that can be performed safely under local anesthesia.

Identification of cultivable microorganisms from primary teeth with necrotic pulps.

The objective of this study was to identify cultivable microorganisms from primary teeth with necrotic pulps. This experimental study included 21 patients of both sexes between 4 and 7 years of age with necrotic pulps in primary teeth. Twenty-one maxillary and mandibular molars containing at least 1 necrotic canal, an abscess or sinus tract, one or more radiolucent areas in the furcation or periapical region, teeth having at least two thirds of root length, and carious lesions directly exposed to the oral environment were included. After antisepsis of the oral cavity, anesthesia of the affected tooth, and isolation and disinfection of the operative field, 3 sterile absorbent paper points were sequentially placed for 30 seconds for the collection of samples. The samples were immediately processed in an anaerobic chamber, and all isolated microorganisms were identified. Anaerobic species (anaerobic facultative and moderate anaerobes) were isolated in all root canals; 68.4% of root canal samples studied showed a polymicrobial nature. Most of the isolate consisted of Bifidobacterium Spp2 and Streptococcus intermedius. Other less frequently encountered species were Actinomyces israelii, Bifidobacterium spp 1, Clostridium spp, and Candida albicans. Results indicate the existence of combinations of bacterial species in root canal infections of the primary dentition with necrotic pulps, anaerobic bacteria predominating.