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2.
Commun Biol ; 5(1): 1027, 2022 09 28.
Article in English | MEDLINE | ID: mdl-36171267

ABSTRACT

Understanding the organisational principles of sperm motility has both evolutionary and applied impact. The emergence of computer aided systems in this field came with the promise of automated quantification and classification, potentially improving our understanding of the determinants of reproductive success. Yet, nowadays the relationship between sperm variability and fertility remains unclear. Here, we characterize pig sperm motility using t-SNE, an embedding method adequate to study behavioural variability. T-SNE reveals a hierarchical organization of sperm motility across ejaculates and individuals, enabling accurate fertility predictions by means of Bayesian logistic regression. Our results show that sperm motility features, like high-speed and straight-lined motion, correlate positively with fertility and are more relevant than other sources of variability. We propose the combined use of embedding methods with Bayesian inference frameworks in order to achieve a better understanding of the relationship between fertility and sperm motility in animals, including humans.


Subject(s)
Semen , Sperm Motility , Animals , Bayes Theorem , Fertility , Humans , Male , Spermatozoa , Swine
3.
GigaByte ; 2022: gigabyte54, 2022.
Article in English | MEDLINE | ID: mdl-36824520

ABSTRACT

The Mosquito Alert dataset includes occurrence records of adult mosquitoes collected worldwide in 2014-2020 through Mosquito Alert, a citizen science system for investigating and managing disease-carrying mosquitoes. Records are linked to citizen science-submitted photographs and validated by entomologists to determine the presence of five targeted European mosquito vectors: Aedes albopictus, Ae. aegypti, Ae. japonicus, Ae. koreicus, and Culex pipiens. Most records are from Spain, reflecting Spanish national and regional funding, but since autumn 2020 substantial records from other European countries are included, thanks to volunteer entomologists coordinated by the AIM-COST Action, and to technological developments to increase scalability. Among other applications, the Mosquito Alert dataset will help develop citizen science-based early warning systems for mosquito-borne disease risk. It can also be reused for modelling vector exposure risk, or to train machine-learning detection and classification routines on the linked images, to assist with data validation and establishing automated alert systems.

4.
Sci Rep ; 11(1): 4718, 2021 02 25.
Article in English | MEDLINE | ID: mdl-33633197

ABSTRACT

Global monitoring of disease vectors is undoubtedly becoming an urgent need as the human population rises and becomes increasingly mobile, international commercial exchanges increase, and climate change expands the habitats of many vector species. Traditional surveillance of mosquitoes, vectors of many diseases, relies on catches, which requires regular manual inspection and reporting, and dedicated personnel, making large-scale monitoring difficult and expensive. New approaches are solving the problem of scalability by relying on smartphones and the Internet to enable novel community-based and digital observatories, where people can upload pictures of mosquitoes whenever they encounter them. An example is the Mosquito Alert citizen science system, which includes a dedicated mobile phone app through which geotagged images are collected. This system provides a viable option for monitoring the spread of various mosquito species across the globe, although it is partly limited by the quality of the citizen scientists' photos. To make the system useful for public health agencies, and to give feedback to the volunteering citizens, the submitted images are inspected and labeled by entomology experts. Although citizen-based data collection can greatly broaden disease-vector monitoring scales, manual inspection of each image is not an easily scalable option in the long run, and the system could be improved through automation. Based on Mosquito Alert's curated database of expert-validated mosquito photos, we trained a deep learning model to find tiger mosquitoes (Aedes albopictus), a species that is responsible for spreading chikungunya, dengue, and Zika among other diseases. The highly accurate 0.96 area under the receiver operating characteristic curve score promises not only a helpful pre-selector for the expert validation process but also an automated classifier giving quick feedback to the app participants, which may help to keep them motivated. In the paper, we also explored the possibilities of using the model to improve future data collection quality as a feedback loop.


Subject(s)
Citizen Science/methods , Culicidae , Deep Learning , Mosquito Vectors , Animal Distribution , Animals , Culicidae/anatomy & histology , Culicidae/classification , Humans , Mobile Applications , Mosquito Control , Mosquito Vectors/anatomy & histology , Mosquito Vectors/classification , Smartphone
5.
J R Soc Interface ; 16(156): 20190103, 2019 07 26.
Article in English | MEDLINE | ID: mdl-31288648

ABSTRACT

How animals explore and acquire knowledge from the environment is a key question in movement ecology. For pollinators that feed on multiple small replenishing nectar resources, the challenge is to learn efficient foraging routes while dynamically acquiring spatial information about new resource locations. Here, we use the behavioural mapping t-Stochastic Neighbouring Embedding algorithm and Shannon entropy to statistically analyse previously published sampling patterns of bumblebees feeding on artificial flowers in the field. We show that bumblebees modulate foraging excursions into distinctive behavioural strategies, characterizing the trade-off dynamics between (i) visiting and exploiting flowers close to the nest, (ii) searching for new routes and resources, and (iii) exploiting learned flower visitation sequences. Experienced bees combine these behavioural strategies even after they find an optimal route minimizing travel distances between flowers. This behavioural variability may help balancing energy costs-benefits and facilitate rapid adaptation to changing environments and the integration of more profitable resources in their routes.


Subject(s)
Bees/physiology , Feeding Behavior/physiology , Flight, Animal/physiology , Learning/physiology , Pollination/physiology , Animals , Flowers
6.
J Hum Evol ; 94: 53-71, 2016 05.
Article in English | MEDLINE | ID: mdl-27178458

ABSTRACT

The late Early Pleistocene site of Untermassfeld, dated to the Jaramillo subchron (ca. 1.07 millions of years ago), is well known for its rich Epivillafranchian fauna. It has also recently yielded stone artefacts attesting hominin occupation. Now, we report here, for the first time, evidence of hominin butchery such as cut marks and intentional hammerstone-related bone breakage. This probable subsistence behaviour was detected in a small faunal subsample recovered from levels with Mode 1 stone tools. The butchered faunal assemblage was found during fieldwork and surveying in fluvial riverbanks (Lower Fluviatile Sands) and channel erosion sediments (Upper Fluviatile Sands). The frequent occurrence of butchery traces on bones of large-sized herd animals (i.e., Bison) may imply a greater need for meat in seasonal habitats characterised by a depletion of nutritive plants in winter. Early access to carcasses, before their consumption by carnivores, provided hominins with sufficient quantities of meat. This access was acquired with a Mode 1 lithic industry, to ensure food procurement and survival at high latitudes in Europe. Stone tools and faunal remains with signs of anthropic intervention recovered at Untermassfeld are evidence of the oldest hominin settlement at continental mid-latitudes (50° N).


Subject(s)
Diet , Hominidae/physiology , Tool Use Behavior , Animals , Archaeology , Fossils , Germany
7.
PLoS One ; 11(3): e0151984, 2016.
Article in English | MEDLINE | ID: mdl-27002631

ABSTRACT

The growing capacity to process and store animal tracks has spurred the development of new methods to segment animal trajectories into elementary units of movement. Key challenges for movement trajectory segmentation are to (i) minimize the need of supervision, (ii) reduce computational costs, (iii) minimize the need of prior assumptions (e.g. simple parametrizations), and (iv) capture biologically meaningful semantics, useful across a broad range of species. We introduce the Expectation-Maximization binary Clustering (EMbC), a general purpose, unsupervised approach to multivariate data clustering. The EMbC is a variant of the Expectation-Maximization Clustering (EMC), a clustering algorithm based on the maximum likelihood estimation of a Gaussian mixture model. This is an iterative algorithm with a closed form step solution and hence a reasonable computational cost. The method looks for a good compromise between statistical soundness and ease and generality of use (by minimizing prior assumptions and favouring the semantic interpretation of the final clustering). Here we focus on the suitability of the EMbC algorithm for behavioural annotation of movement data. We show and discuss the EMbC outputs in both simulated trajectories and empirical movement trajectories including different species and different tracking methodologies. We use synthetic trajectories to assess the performance of EMbC compared to classic EMC and Hidden Markov Models. Empirical trajectories allow us to explore the robustness of the EMbC to data loss and data inaccuracies, and assess the relationship between EMbC output and expert label assignments. Additionally, we suggest a smoothing procedure to account for temporal correlations among labels, and a proper visualization of the output for movement trajectories. Our algorithm is available as an R-package with a set of complementary functions to ease the analysis.


Subject(s)
Behavior, Animal/physiology , Algorithms , Animals , Cluster Analysis , Models, Statistical , Models, Theoretical
8.
Article in English | MEDLINE | ID: mdl-25006765

ABSTRACT

This clinical study assessed at 5 years both implant survival and peri-implant tissue architecture of immediately provisionalized implants placed 4 to 6 months following augmentation with demineralized bovine bone allograft and collagen membrane. Of 23 implants in 19 patients, one implant failed prior to loading (95.6% survival). Implant tissue relationships were stable following implant placement; marginal bone level changes from implant placement to 5 years (mean ± SD: -0.18 ± 0.79 mm, range: -1.6 to 1.4 mm, P = .51), the mesial and distal papilla length changes (mesial mean ± SD: 1.14 ± 0.92 mm, P < .001; distal mean ± SD: 0.74 ± 1.46 mm, P = .04), and the unchanged mucosal zenith location (mean ± SD: 0.24 ± 0.93 mm, P = .15) were recorded. There were no major surgical complications during the 5-year period. When augmentation is required, subsequent dental implant placement in the anterior maxilla may be achieved using immediate placement and provisionalization protocol to attain osseointegration success and stable peri-implant tissue responses.


Subject(s)
Alveolar Process , Esthetics, Dental , Immediate Dental Implant Loading , Animals , Cattle , Humans
9.
Int J Oral Maxillofac Implants ; 29(3): 709-17, 2014.
Article in English | MEDLINE | ID: mdl-24818212

ABSTRACT

PURPOSE: This 5-year prospective multicenter study compared implant survival and success, peri-implant health and soft tissue responses, crestal bone level stability, and complication rates following immediate loading of single OsseoSpeed implants placed in anterior maxillary healed ridges or extraction sockets. MATERIALS AND METHODS: Individuals requiring anterior tooth replacement with single implants were treated and immediately provisionalized. Definitive all-ceramic crowns were placed at 12 weeks. Implant survival, bone levels, soft tissue levels, and peri-implant health were monitored for 5 years. RESULTS: One hundred thirteen patients received implants in fresh sockets (55) and healed ridges (58). After 5 years, 45 and 49 patients remained for evaluation, respectively. During the first year, three implants failed in the extraction socket group (94.6% survival) and one implant failed in the healed ridge group (98.3% survival); this difference was not significant. No further implant failures were recorded. After 5 years, the interproximal crestal bone levels were located a mean of 0.43 ± 0.63 mm and 0.38 ± 0.62 mm from the reference points of implants in sockets and healed ridges (not a significant difference). In both groups, papillae increased over time and peri-implant mucosal zenith positions were stable from the time of definitive crown placement in sockets and healed ridges. Compared to flap surgery for implants in healed ridges, flapless surgery resulted in increased peri-implant mucosal tissue dimension (average, 0.78 ± 1.34 mm vs 0.19 ± 0.79 mm). CONCLUSION: After 5 years, the bone and soft tissue parameters that characterize implant success and contribute to dental implant esthetics were similar following the immediate provisionalization of implants in sockets and healed ridges. The overall tissue responses and reported implant survival support the immediate provisionalization of dental implants in situations involving healed ridges and, under ideal circumstances, extraction sockets.


Subject(s)
Alveolar Process/surgery , Dental Implants, Single-Tooth , Dental Restoration Failure , Immediate Dental Implant Loading , Tooth Socket/surgery , Adult , Crowns , Dental Restoration Failure/statistics & numerical data , Esthetics, Dental , Female , Humans , Male , Maxilla/surgery , Middle Aged , Prospective Studies , Tooth Extraction
10.
Clin Oral Implants Res ; 24(2): 217-23, 2013 Feb.
Article in English | MEDLINE | ID: mdl-22469026

ABSTRACT

AIM: The purpose of this prospective multicenter clinical study was to compare 3 years implant survival, bone and soft tissue changes following immediate loading using single Osseospeed(™) implants (Astra Tech AB, Mölndal, Sweden) installed in healed ridges or extraction sockets. MATERIAL AND METHODS: Implants were provisionally restored the day of surgery using cemented acrylic crowns out of full occlusion. The provisional crowns were replaced after 12 weeks by full-ceramic crowns. Implant survival, bone levels, soft tissue levels and peri-implant health were monitored up to 3 years. RESULTS: 55 patients (22 men, 33 women; mean age 45) had the implant installed in extraction sockets and 58 patients (25 men, 33 women; mean age 42) received conventional implant treatment in healed ridges. Three implants failed in the extraction group and one implant failed in the healed group, all failures occurred before the final crown placement. No further losses occurred during 3 years, giving a statistically comparable survival rate of 94.6% and 98.3%, respectively. The total bone loss after 3 years, compared to implant placement was 0.4 mm (SD 1.5) in healed sites, whilst the immediate sites showed a bone gain of 1.6 mm (SD 2.4) due to bone fill in the alveolus. Papillae retracted with 0.3 and 0.0 mm in the period of provisionalization, but grew back after final crown was placed with 0.3 and 0.5 mm in extraction and healed sites respectively after 3 years. Plaque and inflammation scores were very low throughout the study time, irrespective of treatment modality. CONCLUSIONS: Immediate implants restored at the day of surgery show comparable risk for implant failure, bone loss and midfacial soft tissue recession compared to conventionally installed implants. The 3-years results suggest both hard and soft tissue stability.


Subject(s)
Dental Implants, Single-Tooth , Adult , Alveolar Process/surgery , Crowns , Dental Prosthesis Design , Dental Restoration Failure , Dental Restoration, Temporary , Female , Humans , Male , Middle Aged , Prospective Studies , Tooth Extraction , Tooth Socket/surgery , Treatment Outcome , Wound Healing
11.
Int J Oral Maxillofac Implants ; 27(1): 36-41, 2012.
Article in English | MEDLINE | ID: mdl-22299076

ABSTRACT

PURPOSE: This study evaluated the effects of abutment height, airborne-particle abrasion, and type of cement on the tensile resistance to dislodgement of cement-retained implant restorations. MATERIALS AND METHODS: Three groups of 12 standardized abutments each were prepared with different heights (4 mm, 5 mm, and 6 mm) using a milling machine. Crowns were cast in cobalt-chrome using the lost-wax technique, airborne particle-abraded using 50-Μm aluminum oxide, and cleaned with acetone. Restorations were cemented using a noneugenol acrylic urethane cement, a resin-modified glass ionomer, or a zinc oxide-noneugenol cement. A 5-kg load was applied for 10 minutes. Samples were kept at 37°C and 100% humidity overnight. A tensile force was applied to the crown using a testing machine at a crosshead speed of 5 mm/minute until failure occurred. Next, the abutments were airborne particle-abraded with 50-Μm aluminum oxide, and the cementation and testing procedures were repeated. The effects of cement, abutment height, and surface treatment were evaluated statistically. RESULTS: There were significant differences among the cements. The resin-modified glass ionomer provided the greatest retention in all the tested conditions, while the zinc oxide-noneugenol cement produced the lowest retention values. Significant differences were also detected between 4-mm and 6-mm abutments, with the 6-mm abutments being more retentive. No differences were found between 4-mm and 5-mm abutments or between 5-mm and 6-mm abutments. The effect of airborne-particle abrasion was also found to be significant. A maximum increase of 90 N in retention force was observed after airborne-particle abrasion for the 5-mm abutments cemented with the acrylic urethane cement. CONCLUSIONS: Cement, airborne-particle abrasion, and abutment height can significantly influence retention of implant-supported crowns. Different parameters, including those specific to the patient, should be considered in the selection of a luting agent.


Subject(s)
Dental Abutments , Dental Cements , Dental Prosthesis Retention , Dental Prosthesis, Implant-Supported , Cementation , Chromium Alloys , Crowns , Dental Prosthesis Design , Dental Stress Analysis , Glass Ionomer Cements , Humans , Materials Testing , Resin Cements , Surface Properties , Tensile Strength , Zinc Oxide
12.
Int J Oral Maxillofac Implants ; 25(6): 1222-32, 2010.
Article in English | MEDLINE | ID: mdl-21197501

ABSTRACT

PURPOSE: The primary goal of this study was to compare implant survival 12 months after immediate loading of single implants placed in healed ridges versus extraction sockets. Secondary outcomes were to compare marginal bone adaptation and soft tissue changes over time. MATERIALS AND METHODS: A prospective multicenter clinical investigation was initiated to assess clinical performance of immediately loaded implants in the maxilla. Implant survival was ascertained at the time of impression making (8 to 10 weeks) and after 1 year by clinical stability. Radiographic marginal bone levels, soft tissue levels, and plaque and bleeding scores were compared with baseline values (implant placement and provisionalization). RESULTS: One hundred thirty-nine patients received 157 implants in the maxilla. Single implants with provisional crowns were placed in extraction sockets of 55 patients (58 implants) and in healed ridges of 60 patients (65 implants). In addition, 19 patients (23 implants) required bone grafting prior to implant placement, and 11 implants in 10 patients among all groups were not immediately loaded because of insufficient initial stability after surgery. Three implants (5.2%) failed in extraction sites and one implant (1.5%) failed in a healed ridge. The mean change in marginal bone level 1 year after implant placement was 1.30 mm (SD 2.52) (gain) in extraction sockets and -0.40 mm (SD 1.43) (loss) in healed ridges. The mucosal zenith was stable or moved incisally following definitive crown placement in 83.7% of immediate implants and 87.0% of implants placed in healed ridges. Plaque and inflammation scores were low and did not differ between groups. CONCLUSIONS: The responses of local bone and soft tissues at immediately loaded implants placed in extraction sockets or healed ridges were similar. Furthermore, these 1-year results suggest that clinical management of esthetically critical soft tissue may be predictably achieved in both indications.


Subject(s)
Crowns , Dental Implantation, Endosseous/methods , Dental Implants, Single-Tooth , Dental Prosthesis, Implant-Supported , Tooth Socket/surgery , Adult , Alveolar Process/diagnostic imaging , Alveolar Process/surgery , Dental Abutments , Dental Restoration, Permanent , Dental Restoration, Temporary , Female , Follow-Up Studies , Humans , Male , Maxilla , Middle Aged , Radiography , Survival Analysis , Treatment Outcome , Weight-Bearing
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