Search Results (198)

With the increasing demand for intelligent mobility assistance among the visually impaired, machine guide dogs based on computer vision have emerged as an effective alternative to traditional guide dogs, owing to their flexible deployment and scalability. To enhance their visual perception capabilities in complex urban environments, this paper proposes an improved YOLOv8-based detection algorithm, termed TFP-YOLO, designed to recognize traffic signs such as traffic lights and crosswalks, as well as small obstacle objects including pedestrians and bicycles, thereby improving the target detection performance of machine guide dogs in complex road scenarios. The proposed algorithm incorporates a Triplet Attention mechanism into the backbone network to strengthen the perception of key regions, and integrates a Triple Feature Encoding (TFE) module to achieve collaborative extraction of both local and global features. Additionally, a P2 detection head is introduced to improve the accuracy of small object detection, particularly for traffic lights. Furthermore, the WIoU loss function is adopted to enhance training stability and the model’s generalization capability. Experimental results demonstrate that the proposed algorithm achieves a detection accuracy of 93.9% and a precision of 90.2%, while reducing the number of parameters by 17.2%. These improvements significantly enhance the perception performance of machine guide dogs in identifying traffic information and obstacles, providing strong technical support for subsequent path planning and embedded deployment, and demonstrating considerable practical application value. Full article

Urinary tract infections (UTIs) are a major driver of antimicrobial use in canine veterinary practice. The International Society for Companion Animal Infectious Diseases (ISCAID) guidelines recommend that empirical antimicrobial therapy be guided by locally updated data on pathogen prevalence and resistance patterns. This retrospective study analyzed 201 positive urine cultures obtained via cystocentesis from dogs at a veterinary teaching hospital in northern Italy between 2014 and 2023. The aim was to assess uropathogen distribution and antimicrobial resistance trends before and after the 2019 ISCAID guideline release. Escherichia coli was the predominant isolate (47.5%) showing stable prevalence over time. High resistance rates were observed for amoxicillin (62.4%), whereas resistance to trimethoprim–sulfamethoxazole was lower (33.6%). Importantly, resistance to amoxicillin–clavulanate declined significantly from 52.6% to 25.6% (p = 0.0002). These findings suggest amoxicillin alone may be suboptimal for empirical therapy locally, while amoxicillin–clavulanate and trimethoprim–sulfamethoxazole remain suitable first-line agents. Ongoing local surveillance is essential to support evidence-based antimicrobial stewardship. Full article

Cardiac tumors are rare and linked to high mortality rates in both human and veterinary medicine. Despite their clinical significance, the effects of these tumors on coagulation and cardiac function remain poorly understood. This retrospective study assessed coagulation profiles and echocardiographic parameters in 14 dogs with cardiac tumors compared to 10 healthy controls. Tumors were identified through echocardiography, with further confirmation by computed tomography/magnetic resonance imaging. Coagulation was evaluated using conventional tests (prothrombin time (PT) and activated partial thromboplastin time (aPTT)) and thromboelastography (TEG). The employed conventional coagulation tests and echocardiographic parameters showed no significant differences between the groups. However, TEG revealed a hypercoagulable state in the majority of tumor-bearing dogs (8 out of 14), characterized by shortened reaction and clot formation times, as well as an increased α-angle and coagulation index (p < 0.05–0.001). No significant correlations were found between TEG parameters and echocardiographic indices. This study is the first to demonstrate subclinical hemostatic alterations using TEG in dogs with cardiac neoplasia. The results support the utility of TEG as a more sensitive tool than conventional tests for detecting hypercoagulability, potentially guiding individualized anticoagulant strategies in affected dogs. Full article

Since statistics show a growing trend in blindness and visual impairment, the development of navigation systems supporting Blind and Visually Impaired People (BVIP) must be urgently addressed. Guiding BVIP to a desired destination across indoor and outdoor settings without relying on a pre-installed infrastructure is an open challenge. While numerous solutions have been proposed by researchers in recent decades, a comprehensive navigation system that can support BVIP mobility in mixed and unprepared environments is still missing. This study proposes a novel navigation system that enables BVIP to request directions and be guided to a desired destination across heterogeneous and unprepared settings. To achieve this, the system applies Computer Vision (CV)—namely an integrated Structure from Motion (SfM) pipeline—for tracking the user and exploits Building Information Modelling (BIM) semantics for planning the reference path to reach the destination. Audio Augmented Reality (AAR) technology is adopted for directional guidance delivery due to its intuitive and non-intrusive nature, which allows seamless integration with traditional mobility aids (e.g., white canes or guide dogs). The developed system was tested on a university campus to assess its performance during both path planning and navigation tasks, the latter involving users in both blindfolded and sighted conditions. Quantitative results indicate that the system computed paths in about 10 milliseconds and effectively guided blindfolded users to their destination, achieving performance comparable to that of sighted users. Remarkably, users in blindfolded conditions completed navigation tests with an average deviation from the reference path within the 0.60-meter shoulder width threshold in 100% of the trials, compared to 75% of the tests conducted by sighted users. These findings demonstrate the system’s accuracy in maintaining navigational alignment within acceptable human spatial tolerances. The proposed approach contributes to the advancement of BVIP assistive technologies by enabling scalable, infrastructure-free navigation across heterogeneous environments. Full article

Pulsed radiofrequency (PRF) applied to the dorsal root ganglion (DRG) is commonly performed to manage lumbar radicular pain in human patients. Radiculopathy affecting the seventh lumbar spinal nerve has been identified as key predictor of lumbosacral pain in dogs, yet no published technique exists for placing a PRF electrode adjacent to its DRG to deliver PRF treatment. We describe a novel approach in canine cadavers, integrating ultrasound guidance to locate relevant landmarks and confirm cannula placement under fluoroscopy. Black Indian ink was used to create a localised tissue mark at the tip of a radiofrequency cannula, and subsequent cryosections were performed to measure the distance between the mark and the DRG, revealing a distance of 1.96 ± 1.07 mm. Because this was a cadaveric model, no conclusions can be drawn regarding clinical efficacy or safety in live animals. Nonetheless, these results demonstrate the feasibility of precise electrode positioning using combined imaging in dogs. Future research should explore whether PRF delivered through this approach can indeed alleviate lumbosacral radicular pain in dogs, as well as establish optimal electrode-to-nerve distances and potential safety considerations. Ultimately, this technique could broaden veterinary interventions for chronic spinal pain, improving the quality of life in affected dogs. Full article

Guide dogs are primarily seen as mobility aids for people with visual impairments, but they may also influence users’ psychological well-being and social lives. Benefits of being partnered with a guide dog have been found in several countries but Scandinavian studies are sparse. This qualitative study explores the lived experiences of six Danish guide dog partners through semi-structured interviews. A reflexive thematic analysis found six primary benefits: improved mobility, increased physical activity, enhanced freedom and independence, new social interactions, a strong emotional bond with the dog, and better mental well-being. Users also reported challenges, including frequent distractions caused by the public interacting with the dog, difficulties during the initial adjustment period, increased cleaning, and occasional trouble finding care for the dog. Participants unanimously emphasized the irreplaceable value of their guide dogs and positive socioemotional dimensions of guide dog partnerships. The findings add Scandinavian voices that support existing international research and note three areas of potential improvement: better public education about guide dog etiquette, enhanced support during the adjustment period, and improved care-sharing arrangements. The study underscores the importance of considering guide dogs as both functional aids and sources of emotional and social support. Full article

Periodontal disease in dogs leads to progressive bone loss and adversely impacts overall health. However, cost-effective regenerative strategies are still limited in veterinary practice. This study aimed to develop and evaluate a novel tannic acid (TA)–gelatin-based hydrogel (Gel), incorporating graphene oxide (GO) and hydroxyapatite nanoparticles (HA), as a potential barrier material for guided tissue regeneration (GTR) applications. The hydrogels—Gel, Gel-GO, Gel-HA, and Gel-GO-HA—were characterized for chemical structure, molecular interactions, surface morphology, nanoparticle dispersion, and tensile strength. Cytotoxicity was assessed using L929 fibroblasts (ISO 10993-5), while cell viability/proliferation, morphology, and alkaline phosphatase (ALP) production were evaluated using canine periodontal ligament-derived cells. Results show that crosslinking with tannic acid enhanced the incorporation of graphene oxide and hydroxyapatite nanoparticles via hydrogen bonding into TA–gelatin-based hydrogels. This combination increased surface roughness, reduced degradation rate, and enabled shape memory behavior, critical for guided tissue regeneration (GTR) membranes. The extracts from Gel-HA-GO showed that cytotoxicity was both time- and concentration-dependent in L929 fibroblasts, whereas enhanced cell proliferation and increased ALP production were observed in cultures derived from canine periodontal ligament cells. These findings suggest that TA–gelatin-based hydrogels incorporating GO and HA demonstrated favorable mechanical and physicochemical properties, biocompatibility, and osteogenic potential. These attributes suggest their viability as a promising composite for the development of innovative GTR strategies to address periodontal tissue loss in veterinary medicine. Full article

This study aimed to compare the performance of three hydroxyapatite–β-tricalcium phosphate (HA–β-TCP) collagen composite grafts in a canine model for extraction socket preservation. Eight mongrel dogs underwent atraumatic bilateral mandibular premolar extraction, and sockets were randomly grafted with HBC28 (20% high-crystalline HA, 80% β-TCP bovine collagen), HBC37 (30% HA, 70% β-TCP, bovine collagen), or HPC64 (60% HA, 40% β-TCP, porcine collagen). Grafts differed in their HA–β-TCP ratio and collagen origin and content. Animals were sacrificed at 4 and 12 weeks, and the healing sites were evaluated using micro-computed tomography (micro-CT) and histological analysis. At 12 weeks, all groups showed good socket maintenance with comparable new bone formation. However, histological analysis revealed that HBC28 had significantly higher residual graft volume, while HPC64 demonstrated more extensive graft resorption. Histomorphometric analysis confirmed these findings, with statistically significant differences in residual graft area and bone volume fraction. No inflammatory response or adverse tissue reactions were observed in any group. These results suggest that all three HA–β-TCP collagen composites are biocompatible and suitable for socket preservation, with varying resorption kinetics influenced by graft composition. Selection of graft material may thus be guided by the desired rate of replacement by new bone. Full article

This case report presents a multidisciplinary forensic investigation into a cold case involving a missing person in Italy, likely linked to a homicide that occurred in 2008. The investigation applied a standardized protocol integrating satellite imagery analysis, site reconnaissance, vegetation clearance, ground-penetrating radar (GPR), and cadaver dog (K9) deployment. A dedicated decision tree guided each phase, allowing for efficient allocation of resources and minimizing investigative delays. Although no human remains were recovered, the case demonstrates the practical utility and operational robustness of a structured, evidence-based model that supports decision-making even in the absence of positive findings. The approach highlights the relevance of “negative” results, which, when derived through scientifically validated procedures, offer substantial value by excluding burial scenarios with a high degree of reliability. This case is particularly significant in the Italian forensic context, where the adoption of standardized search protocols remains limited, especially in complex outdoor environments. The integration of geophysical, remote sensing, and canine methodologies—rooted in forensic geoarchaeology—provides a replicable framework that enhances both investigative effectiveness and the evidentiary admissibility of findings in court. The protocol illustrated in this study supports the consistent evaluation of large and morphologically complex areas, reduces the risk of interpretive error, and reinforces the transparency and scientific rigor expected in judicial settings. As such, it offers a model for improving forensic search strategies in both national and international contexts, particularly in long-standing or high-profile missing persons cases. Full article

Radiation-induced keratoconjunctivitis sicca (KCS) is a significant late complication in dogs receiving radiation therapy for intranasal tumors, particularly with hypofractionated intensity-modulated radiation therapy (IMRT). This retrospective case-control study was performed to identify anatomical and dosimetric risk factors for KCS in 15 canine patients treated with IMRT delivered in 4–6 weekly fractions of 8 Gy. Orbital structures were retrospectively contoured, and dose–volume metrics (D50) were calculated. Receiver operating characteristic (ROC) curve analysis and odds ratios were used to evaluate the associations between radiation dose and KCS development. Six dogs (33%) developed KCS within three months post-treatment. Statistically significant dose differences were observed between affected and unaffected eyes for the eyeball, cornea, and retina. ROC analyses identified dose thresholds predictive of KCS: 13.8 Gy (eyeball), 14.9 Gy (cornea), and 17.0 Gy (retina), with the retina showing the highest odds ratio (28.33). To ensure clinical relevance, KCS was diagnosed based on decreased tear production combined with corneal damage to ensure clinical relevance. This study proposes dose thresholds for ocular structures that may guide treatment planning and reduce the risk of KCS in canine patients undergoing IMRT. Further prospective studies are warranted to validate these thresholds and explore mitigation strategies for high-risk cases. Full article

Background: The role of collagen membrane fixation during guided bone regeneration (GBR) remains debatable, particularly in post-extraction sockets with buccal defects and concomitant immediate implant placement. This study evaluated whether or not fixation with titanium pins improved regenerative outcomes. Methods: Six adult Beagle dogs received bilateral extractions of the fourth mandibular premolars. An implant was immediately placed in both the distal alveoli, and standardized buccal bone defects (5 mm height, 3–2 mm width) were prepared. All defects were filled with a slowly resorbing equine xenograft and covered by a resorbable pericardium membrane. At the test sites, the membrane was apically fixed with pins, while no fixation was applied to the control sites. After 3 months of healing, histomorphometric analyses were performed. Results: The vertical bone gain of the buccal crest was 3.2 mm in the test sites (pin group) and 2.9 mm in the control sites (no-pin) (p > 0.754). No significant difference was found in terms of bone-to-implant contact (BIC). However, residual graft particles were located significantly more coronally in the pin group compared to the no-pin group (p = 0.021). Morphometric analyses revealed similar new bone formation within the groups, but with higher amounts of residual xenograft and soft tissue in the pin group. Conclusions: Membrane fixation did not significantly enhance vertical bone gain, and although the slightly higher regeneration in the pin group (3.2 mm vs. 2.9 mm) may hold clinical relevance in esthetically sensitive areas and osseointegration, it appeared to limit apical migration of the grafting material. Full article

This study aims to evaluate the feasibility and accuracy of 3D printing-guided endodontics in the maxillary teeth of dogs. CT data from a Beagle dog were processed to create a 3D model of the maxilla, and virtual root canal pathways were established using SOLIDWORKS software (version 29.0.0.5028). Guided endodontic templates were 3D printed and tested in vitro on 20 maxillary teeth (excluding the third molars), with 36 root canals treated using both guided and conventional methods. Results indicated that 3D printing-guided endodontics provided accurate root canal pathways, with minimal deviations in length (average 3.08 ± 1.75%) and angular alignment (average 2.06° ± 0.5°) compared to conventional methods. This research represents a significant step forward in the application of 3D printing technology in veterinary endodontics, offering a promising alternative to traditional methods for treating complex dental conditions in dogs. Full article

Studies worldwide report cutaneous neoplasms in dogs; however, data in the arid regions of Mexico remain scarce. Here we report the main malignant cutaneous neoplasms diagnosed by fine needle aspiration cytology (FNAC), and describe the associations with age, sex and breed in Mexicali. Neoplastic lesions accounted for 25.52% (698/2735) of the cases, of which 56.59% (395/698) were malignant. The highest prevalence was observed in dogs aged 9–12 years (n = 193), intact males (n = 162), and mixed-breed dogs (n = 247). Round cell neoplasms (n = 309), including lymphoma, transmissible venereal tumors (TVT), and mast cell tumors (MCT), were the most common cell lineage. Using dogs aged 0–4 years as the reference group, dogs aged 9–12 years had 0.241 times the odds of developing malignant neoplasms (95% CI: 0.141–0.415, p = 0.0025). Using neutered males as the reference group, intact females showed 2.499 times the odds of developing malignant neoplasms (95% CI: 1.462–4.271, p = 0.0042). Compared to mixed-breed dogs, Schnauzers (OR = 0.161) showed significantly lower odds of malignancy (95% CI: 0.082–0.317, p = 0.0004), while Pitbull Terriers had 1.748 times more chance of present malignant neoplasia (95% CI: 1.014–3.013, p < 0.0001). This study provides significant epidemiological evidence on canine cutaneous neoplasms in an arid region of Mexico, identifying key risk factors and distribution patterns that can guide preventive, diagnostic, and therapeutic strategies tailored to regional characteristics. Full article

While guide dogs remain the primary aid for visually impaired individuals, robotic guides continue to be an important area of research. This study introduces an indoor guide robot designed to physically assist a blind person by holding their hand with a robotic arm and guiding them to a specified destination. To enable hand-holding, we employed a camera combined with object detection to identify the human hand and a closed-loop control system to manage the robotic arm’s movements. For path planning, we implemented a Dueling Double Deep Q Network (D3QN) enhanced with a genetic algorithm. To address dynamic obstacles, the robot utilizes a depth camera alongside fuzzy logic to control its wheels and navigate around them. A 3D point cloud map is generated to determine the start and end points accurately. The D3QN algorithm, supplemented by variables defined using the genetic algorithm, is then used to plan the robot’s path. As a result, the robot can safely guide blind individuals to their destinations without collisions. Full article

Guide dogs are essential in supporting the autonomy of blind and visually impaired individuals. Austria is the first country to implement a legally mandated, two-stage certification protocol for the official recognition of guide dogs, assessed by an independent authority. The first stage includes two evaluation phases: the dog guides its familiar trainer (Phase 1) and then an unfamiliar blind tester (Phase 2). While Phase 2 ensures an objective assessment of guiding performance, it may also introduce stress due to the unfamiliar handler and separation from the trainer that could impact welfare and behaviour. This study aimed to evaluate whether Phase 2 of the Austrian evaluation protocol elicits higher stress than Phase 1 in guide dogs and, hence, needs to be refined in this regard by comparing physiological and behavioural responses between the two test phases. Fourteen guide dogs were assessed during real evaluations. Salivary cortisol was collected before the evaluation day and at several time points on the evaluation day (before and after each phase). Behavioural responses were coded from video recordings of the first 5 and 15 min of each phase, including stress-related behaviours, task-related performance behaviours, and handler behaviours. Cortisol levels did not differ significantly between the phases. Dogs turned around significantly more often in Phase 2, potentially seeking reassurance, but showed a non-significant trend toward fewer stress-related behaviours. Verbal praise occurred more frequently with the unfamiliar tester. These findings suggest that the current evaluation protocol does not induce substantial physiological or behavioural stress when dogs are guided by an unfamiliar tester, supporting its continued use as a welfare-conscious and objective certification approach that could also potentially serve as a model for other countries. Full article