Head and neck myofibroma: A case series of 16 cases and literature review.

BACKGROUND: This study aimed to explore the clinical, histopathologic, and immunohistochemical characteristics of myofibromas (MFs) affecting the head and neck region. MATERIAL AND METHODS: Formalin-fixed paraffin-embedded tissue blocks of patients diagnosed with MFs in the head and neck were retrieved from the archives of three oral and maxillofacial pathology laboratories. Data including clinical, radiographic, microscopic and immunohistochemical findings, treatment employed, and follow-up status were retrieved from the patient's medical records or pathology reports. RESULTS: Sixteen cases were included in the study. Females were slightly more affected than males. The first and second decades of life were more prevalent. The most common locations were the alveolar ridge and cheek. Although rare, some of the patients were presented with intraosseous lesions. Microscopically, tumors consisted of plump, spindle-shaped myofibroblasts arranged in whorls or fascicles with varying degrees of differentiation. Immunohistochemically, diffuse positivity for vimentin and α-SMA was observed, while Ki-67 mostly showed low immunoreactivity (<5%). Treatment primarily involved complete excision. CONCLUSIONS: MFs in the head and neck region are rare and predominantly affect female patients during the second decade of life. Despite their rarity, central MFs should be considered in the differential diagnosis of intraosseous lesions in infants.

Estimating the burden of care for oral potentially malignant disorders and oral cancer in Brazilian dental practice.

BACKGROUND: Oral cancer (OC) and oral potentially malignant disorders (OPMD) pose significant challenges to public health in Brazil. This study aimed to estimate the prevalence of oral cancer (OC) and oral potentially malignant disorders (OPMD) among patients who would be treated by Brazilian dentists during their careers. MATERIAL AND METHODS: Data on the number of dentists in Brazil were extracted from the 2022 census data, while incidence rates for OC cases were sourced from the Brazilian National Cancer Institute (INCA). Population estimates for Brazil and data on dental check-up rates were obtained from relevant national sources. RESULTS: Our analysis indicates that a general dentist in Brazil can expect to encounter on average two to three OC patients and on average 675 patients with OPMDs over a 35-year career. Regional disparities were observed, with certain regions showing higher than the average number of encounters due to low density of dentists in some rural districts. CONCLUSIONS: Brazilian dentists are likely to confront a substantial number of OC and OPMD cases during their professional tenure, emphasizing the need for public health policies aimed at enhancing dental surgeons' education in oral cancer prevention and early detection.

Synchronous cemento-ossifying fibromas: a systematic review.

BACKGROUND: This systematic review aimed to incorporate published data regarding synchronous cemento-ossifying fibromas (COF), with an analysis of their demographic and clinicopathological characteristics. MATERIAL AND METHODS: Case reports and case series of synchronous COF were searched in PubMed, Web of Science, Scopus, EMBASE, and LILACS according to the PRISMA (2020) statement. Also, a manual search was carried out and the grey literature was assessed. A descriptive statistical analysis was performed. RESULTS: Nineteen studies comprising 20 cases of synchronous COF were included. The mean age at diagnosis was 35 years (±13.8), with a predominance of female patients (n=12/60%). In 13 cases (65%) the mandible and the maxilla were affected simultaneously. In two cases (10%) first-degree relatives (parents or siblings) had been previously diagnosed with COF. The diagnostic hypotheses were reported in 8 cases (40%), with florid cemento-osseous dysplasia, ameloblastic fibroodontoma, calcifying cystic odontogenic tumor, osteoma and cementoblastoma being cited in the differential diagnosis. Among the cases with details about management (n=17), eleven were treated by surgical enucleation and/or excision (64.7%). Follow-up was provided for 10 cases (50%), with a mean period of 44.7±62.19 months. Recurrence occurred in three of informed cases. CONCLUSIONS: Synchronous manifestation of COF is rare. Female patients around the 3rd decade of life are more commonly affected. Bilateral involvement of the mandible and maxilla is the most common clinical presentation.

Phylogenetics and phylogeography of Euphorbia canariensis reveal an extreme Canarian-Asian disjunction but limited inter-island colonization.

Euphorbia canariensis is an iconic endemic species representative of the lowland xerophytic communities of the Canary Islands. It is widely distributed in the archipelago despite having diasporas unspecialized for long-distance dispersal. Here, we reconstructed the evolutionary history of E. canariensis at two levels: a time-calibrated phylogenetic analysis aimed at clarifying interspecific relationships and large-scale biogeographic patterns; and a phylogeographic study focused on the history of colonization across the Canary Islands. For the phylogenetic study, we sequenced the ITS region for E. canariensis and related species of Euphorbia sect. Euphorbia. For the phylogeographic study, we sequenced two cpDNA regions for 28 populations representing the distribution range of E. canariensis. The number of inter-island colonization events was explored using PAICE, a recently developed method that includes a sample size correction. Additionally, we used species distribution modelling (SDM) to evaluate environmental suitability for E. canariensis through time. Phylogenetic results supported a close relationship between E. canariensis and certain Southeast Asian species (E. epiphylloides, E. lacei, E. sessiliflora). In the Canaries, E. canariensis displayed a west-to-east colonization pattern, not conforming to the "progression rule", i.e. the concordance between phylogeographic patterns and island emergence times. We estimated between 20 and 50 inter-island colonization events, all of them in the Quaternary, and SDM suggested a late Quaternary increase in environmental suitability for E. canariensis. The extreme biogeographic disjunction between Macaronesia and Southeast Asia (ca. 11,000 km) parallels that found in a few other genera (Pinus, Dracaena). We hypothesize that these disjunctions are better explained by extinction across north Africa and southwest Asia rather than long-distance dispersal. The relatively low number of inter-island colonization events across the Canaries is congruent with the low dispersal capabilities of E. canariensis.

Lymphomas affecting the submandibular glands.

BACKGROUND: Lymphomas affecting the submandibular glands are very uncommon and few reports are currently available in the literature. Therefore, the aim of the current study is to describe the clinical and microscopic features of an original series of lymphomas affecting the submandibular glands. MATERIAL AND METHODS: The pathology files of two institutions were searched for lymphoma cases affecting the submandibular glands. The original hematoxylin and eosin, and immunohistochemical slides were revised by a pathologist for diagnosis confirmation following the revised 4th edition of the World Health Organization classification of tumours of haematopoietic and lymphoid tissues. Clinical data regarding age, sex, clinical manifestation, treatment, follow-up and status at last appointment were retrieved from the patients' medical charts. RESULTS: During the period investigated, 16 cases were included in the study. Females predominated (10:6) with a mean age of 57.8 years-old. Tumors usually presented as asymptomatic swellings. MALT lymphoma represented the most common subtype, followed by diffuse large B cell lymphoma and follicular lymphoma. Three patients died, one of them affected by plasmablastic lymphoma, one by DLBCL and one by MALT lymphoma. CONCLUSIONS: Low-grade B cell lymphomas predominate in the submandibular glands, but DLBCL and other subtypes may also be rarely diagnosed in this salivary gland.

The use of E-cigarettes as a risk factor for oral potentially malignant disorders and oral cancer: a rapid review of clinical evidence.

BACKGROUND: The popularity of e-cigarettes has increased rapidly in the last decade, particularly among teens and young adults, being advertised as a less harmful alternative to conventional tobacco products. However, in vitro and in vivo studies have evidenced a variable quantity of potentially harmful components and some recognized carcinogens which may cause DNA damage in oral cells. Additionally, evidence suggests that e-cigarettes may play active roles in the pathogenesis of other malignancies, such as lung and bladder cancers. Therefore, this rapid review aimed to assess the available clinical evidence about using e-cigarettes as a risk factor for oral potentially malignant disorders (OPMD) and oral cancer. MATERIAL AND METHODS: A systematic search for English language articles published was performed in PubMed (MEDLINE), Embase, Scopus, and Web of Science. After the study selection process, the authors included twelve clinical studies about OPMD and oral cancer risk in e-cigarette users. RESULTS: The main findings showed the presence of carcinogenic compounds in saliva and morphologic changes, DNA damage, and molecular pathways related to carcinogenesis in the oral cells of e-cigarette users. However, results were inconsistent compared to tobacco smokers and control groups. CONCLUSIONS: the current clinical evidence on this topic is limited and insufficient to support using e-cigarettes as a risk factor for OPMD and oral cancer. Nevertheless, dental care professionals should advise patients responsibly about the potentially harmful effects of e-cigarettes on the oral mucosa cells. Future long-term and well-designed clinical studies are needed.

Systemic therapies for salivary gland carcinomas: an overview of published clinical trials.

BACKGROUND: There is no consensus about effective systemic therapy for salivary gland carcinomas (sgcs). Our aim was summarized the clinical trials assessing the systemic therapies (ST) on sgcs. MATERIAL AND METHODS: Electronic searches were carried out through MEDLINE/pubmed, EMBASE, Scopus, Web of Science, and the Cochrane Library databases, and gray literature. RESULTS: Seventeen different drugs were evaluated, and the most frequent histological subtype was adenoid cystic carcinoma (n=195, 45.5%). Stable disease, observed in 11 ST, achieved the highest rate in adenoid cystic carcinoma treated with sunitinib. The highest complete (11.1%) and partial response (30.5%) rates were seen in androgen receptor-positive tumors treated with leuprorelin acetate. CONCLUSIONS: Despite all the advances in this field, there is yet no effective evidence-based regimen of ST, with all the clinical trials identified showing low rates of complete and partial responses. Further, translational studies are urgently required to characterize molecular targets and effective ST.

Providing inoculum for Didymella bryoniae studies: the effect of light spectrum and storing at low temperature

Abstract The in vitro sporulation of Didymella bryoniae is of great importance for studies that require pure inoculum and in large quantities. Thus, the objectives of this study were to identify the best condition for D. bryoniae sporulation combining different light spectra (UV-A or UV-B light, white light, and continuous dark), with distinct culture media (PDA, V8, ML, and PDAB) and, to evaluate fungus survivability stored at -20°C over time. The fungus samples were only able to sporulate when subjected to the UV-B light treatment, regardless of the culture medium. The highest appearance of spores conidium type was observed in the PDAB medium, and the lowest production occurred in the ML medium. Reproductive structures, such as perithecia and pycnidia, were observed in all culture media. However, there was considerable variation in the amount of each structure between the different culture media. The ML and V8 media showed a greater number of perithecia and the PDA and PDAB media presented a greater proportion of pycnidia compared to perithecia. The storage duration at -20°C did not affect mycelial growth or mycelial growth rate. In conclusion, the UV-B light is essential for D. bryoniae in vitro sporulation. Moreover, the culture medium composition influences the type of fungal structure produced, as well as spores size and quantity. Freezing at -20°C is an efficient technique that can be used to store D. bryoniae for at least five months without loss of viability.

Resumo A esporulação de Didymella bryoniae in vitro é de grande importância para estudos que requerem inóculo puro e em grandes quantidades. Assim, os objetivos deste estudo foram identificar a melhor condição para esporulação de D. bryoniae combinando diferentes espectros de luz (luz UV-A ou UV-B, luz branca e escuro contínuo) com distintos meios de cultura (PDA, V8, ML e PDAB) e, avaliar a sobrevivência do fungo armazenado a -20°C ao longo do tempo. As amostras de fungo só esporularam quando submetidas ao tratamento com luz UV-B, independentemente do meio de cultura. Maior aparecimento de esporos do tipo conídio foi observado no meio PDAB, e a menor produção ocorreu no meio ML. Estruturas reprodutivas, como peritécios e picnídeos, foram observadas em todos os meios de cultura. No entanto, houve uma variação considerável na quantidade de cada estrutura entre os diferentes meios de cultura. Os meios ML e V8 apresentaram maior número de peritécios e os meios PDA e PDAB apresentaram maior proporção de picnídeos em relação aos peritécios. A duração do armazenamento a -20°C não afetou o crescimento micelial ou a taxa de crescimento micelial. Em conclusão, a luz UV-B é essencial para a esporulação de D. bryoniae in vitro. Além disso, a composição do meio de cultura influencia o tipo de estrutura fúngica produzida, bem como o tamanho e a quantidade dos esporos. O congelamento a -20°C é uma técnica eficiente que pode ser usada para armazenar D. bryoniae por pelo menos cinco meses sem perda de viabilidade

Providing inoculum for Didymella bryoniae studies: the effect of light spectrum and storing at low temperature / Fornecendo inóculo para estudos de Didymella bryoniae: o efeito do espectro de luz e armazenamento em baixa temperatura

Abstract The in vitro sporulation of Didymella bryoniae is of great importance for studies that require pure inoculum and in large quantities. Thus, the objectives of this study were to identify the best condition for D. bryoniae sporulation combining different light spectra (UV-A or UV-B light, white light, and continuous dark), with distinct culture media (PDA, V8, ML, and PDAB) and, to evaluate fungus' survivability stored at -20°C over time. The fungus samples were only able to sporulate when subjected to the UV-B light treatment, regardless of the culture medium. The highest appearance of spores conidium type was observed in the PDAB medium, and the lowest production occurred in the ML medium. Reproductive structures, such as perithecia and pycnidia, were observed in all culture media. However, there was considerable variation in the amount of each structure between the different culture media. The ML and V8 media showed a greater number of perithecia and the PDA and PDAB media presented a greater proportion of pycnidia compared to perithecia. The storage duration at -20°C did not affect mycelial growth or mycelial growth rate. In conclusion, the UV-B light is essential for D. bryoniae in vitro sporulation. Moreover, the culture medium composition influences the type of fungal structure produced, as well as spores' size and quantity. Freezing at -20°C is an efficient technique that can be used to store D. bryoniae for at least five months without loss of viability.

Resumo A esporulação de Didymella bryoniae in vitro é de grande importância para estudos que requerem inóculo puro e em grandes quantidades. Assim, os objetivos deste estudo foram identificar a melhor condição para esporulação de D. bryoniae combinando diferentes espectros de luz (luz UV-A ou UV-B, luz branca e escuro contínuo) com distintos meios de cultura (PDA, V8, ML e PDAB) e, avaliar a sobrevivência do fungo armazenado a -20°C ao longo do tempo. As amostras de fungo só esporularam quando submetidas ao tratamento com luz UV-B, independentemente do meio de cultura. Maior aparecimento de esporos do tipo conídio foi observado no meio PDAB, e a menor produção ocorreu no meio ML. Estruturas reprodutivas, como peritécios e picnídeos, foram observadas em todos os meios de cultura. No entanto, houve uma variação considerável na quantidade de cada estrutura entre os diferentes meios de cultura. Os meios ML e V8 apresentaram maior número de peritécios e os meios PDA e PDAB apresentaram maior proporção de picnídeos em relação aos peritécios. A duração do armazenamento a -20°C não afetou o crescimento micelial ou a taxa de crescimento micelial. Em conclusão, a luz UV-B é essencial para a esporulação de D. bryoniae in vitro. Além disso, a composição do meio de cultura influencia o tipo de estrutura fúngica produzida, bem como o tamanho e a quantidade dos esporos. O congelamento a -20°C é uma técnica eficiente que pode ser usada para armazenar D. bryoniae por pelo menos cinco meses sem perda de viabilidade

Evaluating Immune-Related Adverse Events Using PRO-CTCAE in a Phase II Study of Ipilimumab for Hormone-Sensitive Prostate Cancer.

Introduction: Use of the Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE) during chemotherapy is associated with decreased hospitalization rates, improved quality of life, and longer survival. Limited data exist on the benefit of this symptom assessment tool for monitoring immune-related adverse events (irAEs). Methods: We incorporated irAE-related items from the National Cancer Institute's (NCI) PRO-CTCAE in a trial evaluating ipilimumab in combination with androgen deprivation therapy in 16 patients with hormone-sensitive prostate cancer. For comparison, NCI's CTCAE version 4.0 was used by clinicians. Results: IrAE-related PRO-CTCAE surveys and matched CTCAEs (184 pairs) reporting abdominal pain, diarrhea, fatigue, anorexia, nausea, vomiting, rash, and pruritus were collected at each treatment administration and during follow-up. Fatigue, diarrhea, rash, and pruritus were the symptoms most frequently reported by both patients and clinicians. Agreement was lowest for pruritus (κ = 0.10) and highest for rash (κ = 0.64). IrAEs were more commonly reported and of higher grade with PRO-CTCAE scores compared with CTCAE grades. Conclusion: PRO-CTCAEs focused on irAEs capture the patient's immunotherapy experience while complementing the clinician's toxicity assessment measures. Further study is needed to assess PRO-CTCAE's utility in identifying and managing irAEs.

Evaluation of remote teaching in master programs in the Oral Pathology and Oral Medicine during the COVID-19 pandemic. Brazilian multicentric study.

BACKGROUND: With the COVID-19 pandemic, there was a need to adopt online teaching methods in a generalized and sudden way, a situation that led to unprecedented changes in the routine of post-graduate students and research development. This study aimed to analyze the evaluation of remote teaching by graduates of master's degrees and advisors in master's programs in the Oral Pathology and Oral Medicine who needed to adapt to a remote teaching methodology in the pandemic. MATERIAL AND METHODS: This quantitative study evaluated the remote teaching in the perception of master's graduates and advisors from postgraduate programs in Oral Pathology and Oral Medicine. Data were collected through an online Google forms® questionnaire. RESULTS: Participated in the study 14 master graduates and 14 master's advisors. Master graduates evaluated that the professors had a good performance (p=0.001), that the duration of the classes was adequate (p=0.015), that the interaction with professors was satisfactory (p=0.007), that they had good interaction with the advisor (p=0.001), that they were satisfied with the remote guidance process (p=0.038) and that face-to-face practical activities were missed (p=0.002). Master's advisors reported satisfaction with remote teaching, good adaptation (p=0.018) and motivation for remote teaching (p=0.016), they evaluated that students were cooperative in activities (p=0.019) and that face-to-face practical activities were missed (p=0.002). CONCLUSIONS: Despite the difficulties, remote teaching proved to be an effective alternative to face-to-face teaching.

Gingival neoplasms: a multicenter collaborative study of 888 patients in Brazil.

BACKGROUND: To evaluate the prevalence and clinicopathological features of a large series of gingival neoplasms in Brazil. MATERIAL AND METHODS:  All gingival benign and malignant neoplasms were retrieved from the records of six Oral Pathology Services in Brazil, during a 41-year period. Clinical and demographic data, clinical diagnosis, and histopathological data were collected from the patients' clinical charts. For statistical analysis, the chi-square, median test of independent samples and the U Mann-Whitney tests were used, considering a significance of 5%. RESULTS:  From 100,026 oral lesions, 888 (0.9%) were gingival neoplasms. There were 496 (55.9%) males, with a mean age of 54.2 years. Most cases (70.3%) were malignant neoplasms. Nodules (46.2%) and ulcers (38.9%) were the most common clinical appearance for benign and malignant neoplasms, respectively. Squamous cell carcinoma (55.6%) was the most common gingival neoplasm, followed by squamous cell papilloma (19.6%). In 69 (11.1%) malignant neoplasms, the lesions were clinically considered to be inflammatory or of infectious origin. Malignant neoplasms were more common in older men, appeared with larger size, and with a time of complaint shorter than benign neoplasms (p<0.001). CONCLUSIONS:  Benign and malignant tumors may appear as nodules in gingival tissue. In addition, malignant neoplasms, especially squamous cell carcinoma, should be considered in the differential diagnosis of persistent single gingival ulcers.

Draft Genome Sequences of 27 Rhizogenic Agrobacterium Biovar 1 Strains, the Causative Agent of Hairy Root Disease.

Rhizogenic Agrobacterium biovar 1 strains are important plant pathogens that cause hairy root disease in Cucurbitaceae and Solanaceae crops cultivated under hydroponic conditions. In contrast to tumorigenic agrobacteria, only a few genome sequences of rhizogenic agrobacteria are currently available. Here, we report the draft genome sequences of 27 rhizogenic Agrobacterium strains.

Histopathological parameters reported in microinvasive oral squamous cell carcinoma: a systematic review.

BACKGROUND: Microinvasive oral squamous cell carcinoma (OSCCmi) is an incipient stage of oral cancer. Through this systematic review, we aim to assess patterns of histopathological outcomes reported in OSCCmi cases. MATERIAL AND METHODS: An online search in major databases was performed without period restriction, and 2,024 publications in English, Spanish and Portuguese were obtained. After screening and eligibility, 4 studies were selected. The risk of bias was assessed using Joanna Briggs Institute Critical Appraisal Checklist. A descriptive synthesis was conducted. RESULTS: All 4 publications included were retrospective, reporting a total of 116 OSCCmi patients, with a male predominance (1.6:1) and a mean age of 55.9 years. The main parameters considered for microinvasion were tumor thickness (TT) (range 4-10mm) and depth of invasion (DOI) (range 0,02-5mm). Definition, cut-off values, and assessment of microscopic features were not standardized. Other relevant measures such as perineural or lymphovascular invasion and pattern of invasive front were barely described, and cytological/architectural characteristics were not discussed. CONCLUSIONS: TT and DOI are currently the primary histopathological criteria used to define OSCCmi. Nonetheless, the outcomes of this systematic review showed the absence of standardized quantitative parameters to render the diagnosis of microinvasive OSCC. Therefore, additional studies aiming to standardize histopathological features to diagnose OSCCmi are paramount.

Epidemiology and survival outcomes of lip, oral cavity, and oropharyngeal squamous cell carcinoma in a southeast Brazilian population.

BACKGROUND: Lip, oral cavity, and oropharyngeal squamous cell carcinoma (SCC) represent a major health problem in the global scenario. In South America, the highest incidence rates are seen in Brazil. Therefore, the epidemiological and clinical profile and survival outcomes of lip, oral cavity, and oropharyngeal SCC was studied in São Paulo State, Brazil. MATERIAL AND METHODS: The clinicopathological data of 12,099 patients with lip, oral cavity, and oropharyngeal SCC were obtained from hospital cancer registries of the Fundação Oncocentro de São Paulo, Brazil (2010-2015). Survival rates and other analyses were performed using SPSS software. RESULTS: A clear male predominance was observed, particularly for patients with oropharyngeal SCC (88.3%). The average age of patients was higher for lip cases (65 ± 13.5 years) compared to other sites. The schooling level was low for most patients, especially in lip cases (87.9%). Most of the patients with oral cavity (71.8%) and oropharyngeal (86.3%) SCC had advanced-stage (III-IV) disease. However, the majority of lip cases (83.3%) were at an early stage (I-II). Surgical excision was the main treatment for lip (72%) and oral cavity SCC (23.5%), and chemoradiotherapy was the main treatment for oropharyngeal SCC (40.2%). The 5-year overall survival (OS) for patients with lip, oral cavity, and oropharyngeal SCC were 66.3, 30.9, and 22.6%, respectively. Multivariate analysis revealed that the determinants of OS were different for lip, oral cavity, and oropharyngeal SCC, except for those at the clinical stage, which was an independent predictor for all sites. CONCLUSIONS: OS-independent determinants varied according to the affected site. Oral cavity and oropharyngeal SCC presented worse survival rates than those for lip SCC.

MutSα expression predicts a lower disease-free survival in malignant salivary gland tumors: an immunohistochemical study.

BACKGROUND: Appropriate DNA replication is vital to maintain cell integrity at the genomic level. Malfunction on DNA repair mechanisms can have implications related to tumor behavior. Our aim was to evaluate the expression of key complexes of the DNA mismatch-repair system MutSα (hMSH2-hMSH6) and MutSß (hMSH2-hMSH3) in a panel comprising the most common benign and malignant salivary gland tumors (SGT), and to determine their association with disease-free survival. MATERIAL AND METHODS: Ten cases of normal salivary gland (NSG) and 92 of SGT (54 benign and 38 malignant) were retrieved. Immunohistochemistry was performed for hMSH2, hMSH3, hMSH6. Scanned slides were digitally analyzed based on the percentage of positive cells with nuclear staining. Cases were further classified in MutSαhigh and MutSßhigh based on hMSH2-hMSH6 and hMSH3-hMSH6 expression, respectively. RESULTS: hMSH3 expression was lower in malignant SGT compared to NSG and benign cases. Adenoid cystic carcinoma (ACC) cases with perineural invasion presented a lower percentage of hMSH3 positive cells. hMSH6 was downregulated in both benign and malignant SGT compared to NSG. Malignant SGT cases with MutSαhigh expression had lower disease-free survival compared to MutSαlow cases. A 10.26-fold increased risk of presenting local recurrence was observed. CONCLUSIONS: Our findings suggest that a lack of hMSH3 protein function is associated with a more aggressive phenotype (malignancy and perineural invasion) and that MutSα overexpression predicts a poor clinical outcome in malignant SGT.

Efficient quantitative assessment of robot swarms: coverage and targeting Lévy strategies.

Biologically inspiredstrategieshave long been adapted to swarm robotic systems, including biased random walks, reaction to chemotactic cues and long-range coordination. In this paper we applyanalysis toolsdeveloped for modeling biological systems, such as continuum descriptions, to the efficient quantitative characterization of robot swarms. As an illustration, both Brownian and Lévy strategies with a characteristic long-range movement are discussed. As a result we obtain computationally fast methods for the optimization of robot movement laws to achieve a prescribed collective behavior. We show how to compute performance metrics like coverage and hitting times, and illustrate the accuracy and efficiency of our approach for area coverage and search problems. Comparisons between the continuum model and robotic simulations confirm the quantitative agreement and speed up by a factor of over 100 of our approach. Results confirm and quantify the advantage of Lévy strategies over Brownian motion for search and area coverage problems in swarm robotics.

Providing inoculum for Didymella bryoniae studies: the effect of light spectrum and storing at low temperature.

The in vitro sporulation of Didymella bryoniae is of great importance for studies that require pure inoculum and in large quantities. Thus, the objectives of this study were to identify the best condition for D. bryoniae sporulation combining different light spectra (UV-A or UV-B light, white light, and continuous dark), with distinct culture media (PDA, V8, ML, and PDAB) and, to evaluate fungus' survivability stored at -20°C over time. The fungus samples were only able to sporulate when subjected to the UV-B light treatment, regardless of the culture medium. The highest appearance of spores conidium type was observed in the PDAB medium, and the lowest production occurred in the ML medium. Reproductive structures, such as perithecia and pycnidia, were observed in all culture media. However, there was considerable variation in the amount of each structure between the different culture media. The ML and V8 media showed a greater number of perithecia and the PDA and PDAB media presented a greater proportion of pycnidia compared to perithecia. The storage duration at -20°C did not affect mycelial growth or mycelial growth rate. In conclusion, the UV-B light is essential for D. bryoniae in vitro sporulation. Moreover, the culture medium composition influences the type of fungal structure produced, as well as spores' size and quantity. Freezing at -20°C is an efficient technique that can be used to store D. bryoniae for at least five months without loss of viability.

What is the frequency of floor of the mouth lesions? A descritive study of 4,016 cases.

BACKGROUND: The aim of this study was to investigate the frequency of oral lesions in the floor of the mouth from representative oral pathology centres in Latin America. MATERIAL AND METHODS: This study was conducted on biopsies obtained from January of 1978 to December of 2018 at nine Latin America oral and maxillofacial pathology centres. Gender, age and histopathological diagnosis were evaluated. Data were analysed using descriptive methods. Chi-square test was used for pairwise comparisons. RESULTS: From 114,893 samples, 4,016 lesions (3.49%) occurred in the floor of the mouth. Brazil showed 3,777 cases (94%), Mexico 182 cases (4.5%) and Argentina 57 cases (1.4%). Benign lesions represented 65.1% (2,617 cases), followed by 34.9% (1,404 cases) of malignant disorders. Lesions of epithelial origin were more frequent (1,964 cases; 48.9%), followed by salivary glands (1,245 cases; 31%) and soft tissue lesions (475 cases; 11.7%). The most common histological subtypes were oral squamous cell carcinoma (1,347 cases; 33.5%), ranula (724 cases; 18%), oral leukoplakia (476 cases; 11.8%) and inflammatory fibrous hyperplasia (239 cases; 5.9%). The lesion affected males in 2,129 cases and females in 1,897 cases. CONCLUSIONS: In the current study, lesions in the floor of the mouth represented 3.49% of biopsies submitted to oral pathology services and oral squamous cell carcinoma, ranula and leukoplakia were the most common lesions.

Reduction and oxidation kinetics of NiWO4 as an oxygen carrier for hydrogen storage by a chemical looping process.

NiWO4 with a volumetric storage density (VSD) of 496 g L-1 was studied to evaluate its H2 storage potential as an oxygen carrier under a chemical looping (CL) process scheme. The material was synthesized by precipitation and calcined at 950 °C for 5 hours in air. Characterization consisted in XRD, BET surface area, SEM and EDS analysis. NiWO4 hydrogen storage reduction-oxidation evaluation was performed by TGA using 5% v H2/Ar and 2.2% v H2O/Ar at 800 °C. Global kinetics for the reduction step was studied from 730 to 870 °C using 2 to 5% v of H2/Ar. While oxidation kinetics was examined from 730 to 870 °C using 0.8 to 2.2% v H2O/Ar. A hydrogen storage multicycle stability test was performed by exposing NiWO4 to 17 consecutive redox cycles. XRD results of the synthesized material indicate NiWO4 as the only crystalline phase. Fully reduced material found only W and Ni species, while reoxidation led back to NiWO4. BET surface area of synthesized material was 4.25 m2 g-1. SEM results showed fresh NiWO4 composed of non-porous large particles (1-5 µm). After reduction, the material shown a porous coral-like morphology with particles between 50 to 100 nm. EDS analysis results confirmed the compositions of the reduced (Ni + W) and fully oxidized NiWO4 species, respectively. Oxygen carrier reaction conversions for both reduction and regeneration steps were 100%. Global kinetic studies indicate a first order reaction for the two reduction steps and during oxidation, with activation energies of 22.1, 48.4 and 53.4 kJ mol-1 for the two reduction and oxidation steps, respectively. NiWO4 multicycle stability test shown no loss of VSD and fast reduction and oxidation kinetics under the studied conditions after seventeen consecutive redox cycles, which confirms the potential of this material with respect to current oxygen carriers reported in the literature for hydrogen storage applications.