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1.
bioRxiv ; 2024 Apr 09.
Article in English | MEDLINE | ID: mdl-38645204

ABSTRACT

Adaptive decision-making requires consideration of objective risks and rewards associated with each option, as well as subjective preference for risky/safe alternatives. Inaccurate risk/reward estimations can engender excessive risk-taking, a central trait in many psychiatric disorders. The lateral orbitofrontal cortex (lOFC) has been linked to many disorders associated with excessively risky behavior and is ideally situated to mediate risky decision-making. Here, we used single-unit electrophysiology to measure neuronal activity from lOFC of freely moving rats performing in a punishment-based risky decision-making task. Subjects chose between a small, safe reward and a large reward associated with either 0% or 50% risk of concurrent punishment. lOFC activity repeatedly encoded current risk in the environment throughout the decision-making sequence, signaling risk before, during, and after a choice. In addition, lOFC encoded reward magnitude, although this information was only evident during action selection. A Random Forest classifier successfully used neural data accurately to predict the risk of punishment in any given trial, and the ability to predict choice via lOFC activity differentiated between and risk-preferring and risk-averse rats. Finally, risk preferring subjects demonstrated reduced lOFC encoding of risk and increased encoding of reward magnitude. These findings suggest lOFC may serve as a central decision-making hub in which external, environmental information converges with internal, subjective information to guide decision-making in the face of punishment risk.

2.
Bioengineering (Basel) ; 11(3)2024 Feb 22.
Article in English | MEDLINE | ID: mdl-38534478

ABSTRACT

Ascending aortic aneurysm (AAoA) is a silent disease with high mortality; however, the factors associated with a worse prognosis are not completely understood. The objective of this observational, longitudinal, single-center study was to identify the hemodynamic patterns and their influence on AAoA growth using computational fluid dynamics (CFD), focusing on the effects of geometrical variations on aortic hemodynamics. Personalized anatomic models were obtained from angiotomography scans of 30 patients in two different years (with intervals of one to three years between them), of which 16 (53%) showed aneurysm growth (defined as an increase in the ascending aorta volume by 5% or more). Numerically determined velocity and pressure fields were compared with the outcome of aneurysm growth. Through a statistical analysis, hemodynamic characteristics were found to be associated with aneurysm growth: average and maximum high pressure (superior to 100 Pa); average and maximum high wall shear stress (superior to 7 Pa) combined with high pressure (>100 Pa); and stress load over time (maximum pressure multiplied by the time interval between the exams). This study provides insights into a worse prognosis of this serious disease and may collaborate for the expansion of knowledge about mechanobiology in the progression of AAoA.

3.
Sensors (Basel) ; 23(16)2023 Aug 15.
Article in English | MEDLINE | ID: mdl-37631721

ABSTRACT

Anomaly detection in sequences is a complex problem in security and surveillance. With the exponential growth of surveillance cameras in urban roads, automating them to analyze the data and automatically identify anomalous events efficiently is essential. This paper presents a methodology to detect anomalous events in urban sequences using pre-trained convolutional neural networks (CNN) and super-resolution (SR) models. The proposal is composed of two parts. In the offline stage, the pre-trained CNN model evaluated a large dataset of urban sequences to detect and establish the common locations of the elements of interest. Analyzing the offline sequences, a density matrix is calculated to learn the spatial patterns and identify the most frequent locations of these elements. Based on probabilities previously calculated from the offline analysis, the pre-trained CNN, now in an online stage, assesses the probability of anomalies appearing in the real-time sequence using the density matrix. Experimental results demonstrate the effectiveness of the presented approach in detecting several anomalies, such as unusual pedestrian routes. This research contributes to urban surveillance by providing a practical and reliable method to improve public safety in urban environments. The proposed methodology can assist city management authorities in proactively detecting anomalies, thus enabling timely reaction and improving urban safety.

4.
Article in English | MEDLINE | ID: mdl-37200130

ABSTRACT

Physical walking is often considered the gold standard for VR travel whenever feasible. However, limited free-space walking areas in the real-world do not allow exploring larger-scale virtual environments by actual walking. Therefore, users often require handheld controllers for navigation, which can reduce believability, interfere with simultaneous interaction tasks, and exacerbate adverse effects such as motion sickness and disorientation. To investigate alternative locomotion options, we compared handheld Controller (thumbstick-based) and physical walking versus a seated (HeadJoystick) and standing/stepping (NaviBoard) leaning-based locomotion interface, where seated/standing users travel by moving their head toward the target direction. Rotations were always physically performed. To compare these interfaces, we designed a novel simultaneous locomotion and object interaction task, where users needed to keep touching the center of upward moving target balloons with their virtual lightsaber, while simultaneously staying inside a horizontally moving enclosure. Walking resulted in the best locomotion, interaction, and combined performances while the controller performed worst. Leaning-based interfaces improved user experience and performance compared to Controller, especially when standing/stepping using NaviBoard, but did not reach walking performance. That is, leaning-based interfaces HeadJoystick (sitting) and NaviBoard (standing) that provided additional physical self-motion cues compared to controller improved enjoyment, preference, spatial presence, vection intensity, motion sickness, as well as performance for locomotion, object interaction, and combined locomotion and object interaction. Our results also showed that less embodied interfaces (and in particular the controller) caused a more pronounced performance deterioration when increasing locomotion speed. Moreover, observed differences between our interfaces were not affected by repeated interface usage.

5.
IEEE Trans Vis Comput Graph ; 29(12): 5265-5281, 2023 Dec.
Article in English | MEDLINE | ID: mdl-36112551

ABSTRACT

Continuous locomotion in VR provides uninterrupted optical flow, which mimics real-world locomotion and supports path integration . However, optical flow limits the maximum speed and acceleration that can be effectively used without inducing cybersickness. In contrast, teleportation provides neither optical flow nor acceleration cues, and users can jump to any length without increasing cybersickness. However, teleportation cannot support continuous spatial updating and can increase disorientation. Thus, we designed 'HyperJump' in an attempt to merge benefits from continuous locomotion and teleportation. HyperJump adds iterative jumps every half a second on top of the continuous movement and was hypothesized to facilitate faster travel without compromising spatial awareness/orientation. In a user study, Participants travelled around a naturalistic virtual city with and without HyperJump (equivalent maximum speed). They followed waypoints to new landmarks, stopped near them and pointed back to all previously visited landmarks in random order. HyperJump was added to two continuous locomotion interfaces (controller- and leaning-based). Participants had better spatial awareness/orientation with leaning-based interfaces compared to controller-based (assessed via rapid pointing). With HyperJump, participants travelled significantly faster, while staying on the desired course without impairing their spatial knowledge. This provides evidence that optical flow can be effectively limited such that it facilitates faster travel without compromising spatial orientation. In future design iterations, we plan to utilize audio-visual effects to support jumping metaphors that help users better anticipate and interpret jumps, and use much larger virtual environments requiring faster speeds, where cybersickness will become increasingly prevalent and thus teleporting will become more important.

6.
Front Microbiol ; 13: 951173, 2022.
Article in English | MEDLINE | ID: mdl-36051765

ABSTRACT

Pasteurellaceae family members obtain iron directly from host proteins or through siderophore-dependent mechanisms. Although Gallibacterum anatis expresses different virulence factors, its response to growth under iron restriction is unknown. G. anatis cultured in the presence of 2,2'-dipyridyl, up-expressed an approximately 65 kDa protein and repressed the expression of a 70 kDa protein. MALDI-TOF analysis of those proteins indicated homology with CirA (65 kDa), a protein involved in iron-siderophore acquisition in Mannheimia succinoproducens and a TonB-dependent receptor (70 kDa protein), a protein that binds chicken hemoglobin; however, G. anatis siderophore production was not detected by chromo azurol S (CAS)-BHI agar determination. This putative G. anatis siderophore receptor is under Fur control, but not the hemoglobin binding protein, as observed in G. anatis 12656-12 fur mutant (Ω fur 126.13) grown in the presence or not of 2,2'-dipyridyl. The addition of FeCl3 to the culture medium diminished the growth and biofilm production in approximately 30% and 35%, respectively, in the wild-type strain, but the growth of Ω fur 126.13 strain was not affected and biofilm production increased in 35%. G. anatis Ω fur 126.13 presented lower virulence when it was inoculated to 35-day-old chickens in comparison to the wild-type strain. The induction of more than one iron uptake mechanism could benefit pathogenic microorganisms such as Gallibacterium.

7.
Trop Anim Health Prod ; 51(1): 17-24, 2019 Jan.
Article in English | MEDLINE | ID: mdl-29982910

ABSTRACT

Lameness is a severe welfare problem in cattle and has a detrimental effect on longevity, productivity, and reproductive performance. This study aimed to describe the frequency and distribution of foot lesions in cattle using hoof trimming records over a period of 6 years in the Province of Antioquia (Colombia). The data collection instrument enabled differentiation between limbs, digits, and views. The Claw Lesion Identification in Dairy Cattle brochure was the reference for foot lesion identification. A total of 1814 foot lesions observations, recorded from 1120 cows in 71 herds, were analyzed and 11 different foot lesions were identified. Non-infectious foot lesions were more common than infectious (94.4 vs 5.6%). White line disease was more frequently observed in the hind limbs (79.6%) compared to the front limbs (20.4%), and more frequent in medial claws of the front limbs (70.3%) compared to lateral claws (29.7%). In hind limbs, the lateral claws were more commonly affected (65.7%) compared to the medial claws (34.3%). Claw zone 3 was affected in 61.3% of the cases, followed by zones 2 (21.7%) and 1 (17%). Although our data are from a limited area of the country, they are consistent with published and anecdotal reports of foot lesions in cattle in Colombia and worldwide. Our results suggest that there is need for additional prospective research under Colombian dairy cattle management conditions to better understand the lameness and benefit of trimming intervention.


Subject(s)
Cattle Diseases/diagnosis , Foot Diseases/veterinary , Hoof and Claw/pathology , Animal Husbandry , Animals , Cattle , Cattle Diseases/epidemiology , Cattle Diseases/pathology , Colombia/epidemiology , Female , Foot Diseases/diagnosis , Foot Diseases/epidemiology , Prospective Studies
8.
Dig Dis Sci ; 56(7): 1976-80, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21221789

ABSTRACT

BACKGROUND: The effect of gastroesophageal reflux disease (GERD) on health-related quality of life (HRQL) in COPD has never been assessed. AIM: To evaluate HRQL in patients with COPD alone compared with those with both COPD and continuing GERD symptoms. METHODS: A questionnaire-based, cross-sectional survey was performed. Subjects were recruited from the outpatient pulmonary clinics at the University of Florida Health Science Center/Jacksonville. Included patients had an established diagnosis of COPD. Exclusion criteria were respiratory disorders other than COPD, known esophageal disease, active peptic ulcer disease, Zollinger-Ellison syndrome, mastocytosis, scleroderma, and current alcohol abuse. Those meeting the criteria and agreeing to participate were asked to complete the Mayo Clinic GERQ and SF-36 questionnaires, by either personal or telephone interview. Clinically significant reflux was defined as heartburn and/or acid regurgitation weekly. Study patients were divided into two groups for HRQL analysis based on the GERQ response: COPD+/GERD+ and COPD only. Statistical analysis was performed using the Mann-Whitney-Wilcoxon T test for unequal variables and linear regression was performed using ANOVA. All data are expressed as mean and standard deviation. RESULTS: Eighty-six patients completed both questionnaires. Males were 55% and COPD+/GERD+ patients comprised 37% of the study group. Compared with COPD only, HRQL was reduced across all measures for the COPD+ GERD+ patients and achieved significance for bodily pain (P < 0.02), mental health (P < 0.05), and physical component score (P < 0.05). CONCLUSION: Patients with COPD and continuing GERD symptoms have reduced HRQL in comparison with those with COPD alone.


Subject(s)
Gastroesophageal Reflux/complications , Pulmonary Disease, Chronic Obstructive/complications , Pulmonary Disease, Chronic Obstructive/physiopathology , Quality of Life , Aged , Comorbidity , Cross-Sectional Studies , Female , Gastroesophageal Reflux/epidemiology , Heartburn/epidemiology , Heartburn/physiopathology , Humans , Male , Middle Aged , Pulmonary Disease, Chronic Obstructive/epidemiology , Respiratory Function Tests , Smoking , Surveys and Questionnaires , Treatment Outcome
9.
Chest ; 130(4): 1096-101, 2006 Oct.
Article in English | MEDLINE | ID: mdl-17035443

ABSTRACT

BACKGROUND AND AIMS: The impact of gastroesophageal reflux disease (GERD) on exacerbations of COPD has never been evaluated. The aims of this investigation were to determine the prevalence of gastroesophageal reflux (GER) symptoms in COPD patients and the effect of GER on the rate of exacerbations of COPD per year. METHODS: A questionnaire-based, cross sectional survey was performed. Subjects were recruited from the outpatient pulmonary clinics at the University of Florida Health Science Center/Jacksonville. Included patients had an established diagnosis of COPD. Exclusion criteria were respiratory disorders other than COPD, known esophageal disease, active peptic ulcer disease, Zollinger-Ellison syndrome, mastocytosis, scleroderma, and current alcohol abuse. Those meeting criteria and agreeing to participate were asked to complete the Mayo Clinic GERD questionnaire by either personal/telephone interview. Clinically significant reflux was defined as heartburn and/or acid regurgitation weekly. Other outcome measures noted were frequency and type of COPD exacerbations. Statistical analysis was performed using the Fisher exact test for categorical data and the independent t test for interval data. RESULTS: Eighty-six patients were enrolled and interviewed (mean age, 67.5 years). Male patients accounted for 55% of the study group. Overall, 37% of patients reported GER symptoms. The mean FEV(1) percentage of predicted was similar in those with or without GER. The rate of exacerbations of COPD was twice as high in patients with GER symptoms compared to those without GER symptoms (3.2/yr vs 1.6/yr, p = 0.02). CONCLUSIONS: The presence of GER symptoms appears to be associated with increased exacerbations of COPD.


Subject(s)
Gastroesophageal Reflux/complications , Gastroesophageal Reflux/epidemiology , Pulmonary Disease, Chronic Obstructive/epidemiology , Pulmonary Disease, Chronic Obstructive/etiology , Aged , Antacids/administration & dosage , Anti-Ulcer Agents/administration & dosage , Comorbidity , Disease Progression , Drug Therapy, Combination , Female , Follow-Up Studies , Gastroesophageal Reflux/drug therapy , Histamine H2 Antagonists/administration & dosage , Humans , Male , Middle Aged , Proton Pump Inhibitors , Smoking/adverse effects , Smoking/epidemiology , Statistics as Topic , Treatment Outcome
10.
Urol Oncol ; 23(1): 22-6, 2005.
Article in English | MEDLINE | ID: mdl-15885579

ABSTRACT

Leiomyosarcomas of vascular origin is a rare and aggressive pathology, its presentation on the renal vein is infrequent, of which 29 cases have been reported world-wide. We describe a case of a 76 year-old woman, who presented with intermittent left flank pain, irradiated to the lumbar region of 6 months duration. A left radical nephrectomy with en-bloc resection of a para-aortic tumor was performed. Microscopic examination of the specimen reported a moderately differentiated leiomyosarcoma, originated in the wall of the renal vein. The patient received adjuvant chemotherapy and radiation therapy. The tumor recurred in the liver. After 24 months from the primary surgery, the patient is alive with evidence of multiple metastatic spread to the liver. She is now under palliative care.


Subject(s)
Leiomyosarcoma/pathology , Renal Veins/pathology , Vascular Neoplasms/pathology , Aged , Combined Modality Therapy , Female , Humans , Immunoenzyme Techniques , Leiomyosarcoma/diagnostic imaging , Leiomyosarcoma/therapy , Renal Veins/diagnostic imaging , Tomography, X-Ray Computed , Vascular Neoplasms/diagnostic imaging , Vascular Neoplasms/therapy
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