Seasonal variation in the biological succession of marine diatoms over 316L stainless steel in a coastal environment of Chile.

Characterizing seasonal changes in diatom community profiles in coastal environments is scarce worldwide. Despite diatoms being prevalent in microfouling, their role in microbially influenced corrosion of metallic materials remains poorly understood. This study reports the effect of seasonal variations on the settlement of marine diatoms and corrosion of 316 L stainless steel surfaces exposed to Chilean coastal seawater. Electron microscopy imaging revealed a diverse assembly of diatoms, exhibiting pronounced differences at genus level between summer and winter seasons, with a significant delay in diatom settlement during winter. Electrochemical measurements indicated an active role of diatoms in increasing corrosion current during biofilm development. While the final diatom composition was similar irrespective of the season, the analyses of diatom assemblages over time differed, showing faster colonization when silicate and nitrate were available. This study lays the foundation for future research on the dominant season-specific genera of diatoms to unveil the microbial interactions that could contribute to corrosion and to evaluate their potential as bioindicators for alternative surveillance strategies.

Intercultural sensitivity in Chilean healthcare profession students.

Each culture has unique health care related values, habits, perceptions, expectations, norms, etc., that makes cultural competence an important attribute to be developed by healthcare professionals, to ensure they provide effective treatment. Intercultural sensitivity (IS) is the affective dimension of cultural competence. The objective of this study is to explore the self-perceived level of IS in first and last year students of three health sciences professions (i.e., Dentistry, Medicine, and Nursing) at the Universidad de la Frontera, Temuco, Chile. This study adopted a cross-sectional design and a group comparison (e.g., year of study). 312 students completed the Intercultural Sensitivity Scale (ISS). Findings showed that overall ISS scores ranged from 1.83 to 4.94, with a mean score of 4.11 (s.d. 0.43). Group comparison between first and final year students showed statistically significant differences (4.18 vs. 4.00; p < 0.001). Medical and nursing students had a significantly higher overall mean IS score compared to dental students (4.21 and 4.16, respectively vs. 4.02; p < 0.01). There were also significant differences between three factors (interaction engagement; interaction confidence; and interaction enjoyment) by healthcare profession. These findings allow for discussion of the need for explicit incorporation and development of cultural competence in on health care professional curricula. Longitudinal research is needed to explore how IS changes over time, along with generating qualitative data from the student populations IS experiences and exposure.

Translation and validation into Spanish of the oral health self-efficacy scale in Chilean older adults.

BACKGROUND: Population ageing poses a challenge to improving the well-being of older adults, particularly in terms of oral health. Promoting self-efficacy in oral health behaviours is crucial for maintaining this population's health and quality of life. The Oral Health Self-Efficacy Scale (OHSES) has been widely used to assess dental self-efficacy and is considered comprehensive and reliable. However, there is a need to validate OHSES for Spanish-speaking older adults. This study aimed to assess the reliability and validity of the translated questionnaire for use in the older Chilean population. METHODS: A sample of 188 older adults, aged 60 years and above residing independently in the community, were recruited by accessing databases from the National Senior Citizen Service and various community organisations within the region of La Araucanía. The participants underwent comprehensive oral examinations and oral health interviews, focusing on variables such as OHSES, Oral health-related quality of life (OHIP-14Sp), assessment of remaining teeth, knowledge and attitudes toward oral health, and sociodemographic characteristics. The validity of the translated questionnaire was assessed through translation and cross-cultural adaptation, cognitive debriefing, and face and content validation. The psychometric properties of the questionnaire were evaluated through measures of internal consistency (Cronbach's alpha), content validity (Content validity index), construct validity (factor analysis and Pearson correlation analysis), and test-retest reliability (intraclass correlation). RESULTS: The Spanish version of OHSES demonstrated adequate face and content validity. The confirmatory factor analysis confirmed a two-factor scale with 7 items for a better fit. The scale demonstrated high internal consistency (Cronbach's alpha = 0.821) and acceptable test-retest reliability (ICC = 0.411). Correlations were found between the OHSES score, the number of remaining teeth, knowledge and attitudes towards oral health, and the OHIP-14Sp (p < 0.01). CONCLUSIONS: This study confirms the validity of the Spanish version of the Oral Health Self-Efficacy Scale for older adults in Chile. The scale is expected to be helpful in assessing self-efficacy in dental interventions and collecting data for international comparisons. This research opens new dimensions in patient-reported assessment of oral health.

Orthodontic treatment demand for fixed treatment and aligners among young adults in middle Europe and South America - a questionnaire study.

BACKGROUND: Patients experiencing any malocclusion, may desire for treatment. However, there is no scientific information orthodontic treatment demand and the knowledge of young adults about orthodontic treatment. The aim of the study was to assess orthodontic treatment demand in young adults from Poland and Chile, their previous orthodontic experience and their knowledge on fixed and aligner orthodontic treatment. METHODS: The target group comprised people aged 18-30. The sample size was estimated as above 400 for each country. The survey was carried out in Polish and Spanish within 3 months and consisted of 25 questions delivered via social media. Comparisons were made between countries, age subgroups and gender. RESULTS: The response rate was 1,99%, what stands for 1092 responses, 670 from Chile and 422 from Poland, respectively. The percentage of young adults who were already treated was 42,9% in Poland and 25,0% in Chile. The ones planning to have orthodontic treatment within a year counted for 11,8% in Poland and 5,3% in Chile. Most young adults who want to be treated (20,6%) rely on doctor's recommendation on type of appliance while 14,7% of all respondents are interested solely in aligners. Most respondents have heard about aligners (58%). Direct provider-to-customer service without a doctor is not acceptable, neither in Poland (85,1%) nor in Chile (64,8%). Most young adults provided incorrect answers referring various aspects of aligner treatment. CONCLUSIONS: In both countries, patients demand to be treated and monitored by the orthodontist. A high percentage of patients want to be treated exclusively with aligners. Direct-to-consumer orthodontics does not seem attractive to patients. Young adults do not have adequate knowledge referring to aligner treatment. Many people want to be treated despite a previous orthodontic treatment.

A temporal and spatial study of genetic structure in four species of bladed Bangiales (Rhodophyta) from the southeastern Pacific coast of Chile.

The coastline is a heterogeneous and highly dynamic environment influenced by abiotic and biotic variables affecting the temporal stability of genetic diversity and structure of marine organisms. The aim of this study was to determine how much the genetic structure of four species of marine Bangiales vary in time and space. Partial sequences of the cytochrome oxidase I (COI) gene obtained from two Pyropia (Py. sp. CHJ and Py. orbicularis) and two Porphyra (P. mumfordii and P. sp. FIH) species were used to compare the effect of the 40° S/41° S biogeographic break (spatial-regional scale) and the one of the Valdivia River discharges (spatial-local scale) and determine their temporal stability. Four seasonal samplings were taken during 1 year at five sites, one site located in Melinka (Magallanes province) and four sites along the coast of Valdivia (Intermediate area), on both sides of the river mouth. Results showed a strong genetic spatial structure at regional scale (ΦST > 0.4) in Py. sp. CHJ, Py. orbicularis, and P. mumfordii, congruent with the 41° S/42° S biogeographic break. A potential barrier to gene flow, related to the Valdivia River discharge, was detected only in P. mumfordii. In P. sp. FIH, spatial genetic structure was not detected at any scale. The genetic structure of all four species is stable throughout the year. The potential effect of main currents and river discharge in limiting the transport of Bangiales spores are discussed. We propose that both a restricted propagule dispersal and the formation potential for persistent banks of microscopic stages could lead to a temporally stable spatial partitioning of genetic variation in bladed Bangiales.

Chewing Analysis by Means of Electromagnetic Articulography: Current Developments and New Possibilities.

Chewing is a complex procedure that involves sensory feedback and motor impulses controlled by the trigeminal system in the brainstem. The analysis of mandibular movement is a first approximation to understanding these mechanisms. Several recording methods have been tested to achieve this. Video, ultrasound, the use of external markers and kinesiographs are examples of recording systems used in research. Electromagnetic articulography is an alternative method to those previously mentioned. It consists of the use of electromagnetic fields and receiver coils. The receiver coils are placed on the points of interest and the 3D coordinates of movement are saved in binary files. In the Oral Physiology Laboratory of the Dental Sciences Research Center (Centro de Investigación en Ciencias Odontológicas-CICO), in the Faculty of Dentistry at the Universidad de La Frontera (Temuco, Chile) several research studies have been carried out using the AG501 3D EMA articulograph (Carstens Medizinelektronik, Lenglern, Germany). With this device, they developed a series of protocols to record mandibular movement and obtain new information, such as the 3D Posselt polygon, the area of each polygon, individualized masticatory cycles and speed and acceleration profiles. Other investigations have analyzed these parameters, but separately. The AG501 allows for holistic analysis of all these data without altering natural movement. A limitation of this technology is the interference generated by its metallic elements. The aim of the present work is to show the developed methods used to record mandibular movement in the CICO, using the AG501 and compare them with others used in several research studies.

[Intercultural Competences in Chilean Dental Education for Inclusive Healthcare]. / Identificación de contenidos de pertinencia intercultural para la atención de salud para el plan de estudios de odontología.

INTRODUCTION: Cultural diversity in Chile and inequities in access and quality of care require the development of cultural competencies in health professionals. Internationally, cultural competence has been integrated into the curricula of health professional programs; however, in Chile it is still in its early stages. METHODS: A mixed methodology included documentary review (searches and analysis in databases and official documents), key informant interviews and expert consensus. The interviews were transcribed verbatim, and thematic analysis was carried out using ATLAS.ti software. RESULTS: The documentary review identified domains, objectives and instruments used to measure cultural competence in dentistry. The interviews revealed four main categories: conceptions of health, facilitators and barriers, and characteristics of health professionals. Experts developed, evaluated and agreed upon content and learning outcomes. CONCLUSION: Including cultural competence in dental curricula is essential for more inclusive and culturally safe health care. Its longitudinal integration into various courses, employing effective teaching and assessment methodologies, is recommended. The results of this study provide a guide to identifying the knowledge, skills, and attitudes needed to train health professionals who ultimately deliver appropriate health care with cultural pertinence.

[Alarming signals: Worsening obesity, physical inactivity and high perception of stress in first-year medical and dental students in Chile]. / Señales de Alarma: Empeoramiento de la Obesidad, Inactividad Física y Alta Percepción de Estrés en Estudiantes de Primer Año de la Facultad de Medicina y Odontología de la Universidad de Chile.

BACKGROUND: The high prevalence of obesity, smoking, and physical inactivity in Chile despite government-sponsored measures and campaigns, along with others in the last 30 years, suggests additional reinforcement of these efforts at the primary care level. OBJECTIVES: To determine if lifestyles and modifiable health risk factors in first-year students from the University of Chile Faculties of Medicine and Dentistry, potential future promoters of healthy lifestyles, show changes throughout their first academic year. METHODS: In a randomized stratified sample of 388 students according to sex and chosen career weight, height, waist circumference, waist circumference-weight ratio, food consumption, smoking prevalence and dependence, alcohol use, perceived stress level, and physical activity were measured at the first week, 3 and 6 months after their admission. The Cochrane test assessed dichotomic variables, and the Friedman test was used for nonparametric values. RESULTS: 253 students (186 women) completed the follow-up. A significant worsening of obesity (general and abdominal) and physical inactivity, persistent moderate and high-stress perception, and smoking prevalence were documented throughout the study period. CONCLUSIONS: The progressive obesity and physical inactivity, high-stress perception, and persistent smoking prevalence in the first year of academic life suggest considering measures in the curricular academic structure that facilitate adjustments in the student's lifestyles. Future follow-up of this cohort, increasing participants, and assessing students' mental health are planned.

Structural validity and reliability of the "Oral Health Assessment Tool" applied by speech-language therapists in a population of older Chilean people.

BACKGROUND: A good state of oral health allows people to communicate and eat. This topic is relevant in older people given its close relationship with their general health. At present, health challenges are directed at detecting and preventing oral disorders and are seen to exclusively by dentists, because the existing instruments can only be applied by them. However, speech-language therapists undergo similar training, which would allow them to collaborate in these processes. In this context, the Oral Health Assessment Tool (OHAT) is a detection instrument with good psychometric properties that is currently available for non-dental use. The objective of this study is the translation into Chilean Spanish of the OHAT and a structural validation of that version for application by these professionals. MATERIALS AND METHODS: A mixed qualitative-quantitative study was carried out. The OHAT instrument was adapted to Chilean Spanish and subsequently subject to structural validity and evaluation of internal consistency reliability, as well as a valuation of its reproducibility in 286 older people (166 female, 120 male) from different health contexts. RESULTS: The cultural adaptation of the instrument proved to be semantically consistent with the original instrument. Its application was considered to be speedy and simple in the pre-test. The confirmatory factor analysis evidenced the unidimensionality of the OHAT. In addition, the instrument shows good internal consistency and test-retest reliability. CONCLUSIONS: The OHAT instrument was considered to possess adequate structural validity and test-retest reliability properties. Its usefulness in the context of oral health disorders of this population in Chile is discussed.

Association between number of remaining teeth and incident depression in a rural Chilean cohort.

OBJECTIVES: Previous studies have established an association between tooth loss and depression. However, longitudinal evidence is scarce and needs to be verified in other populations. The aim of this study was to examine the longitudinal association between the number of remaining teeth and incident depression at 2- and 4-years follow-up in individuals enrolled in the Maule cohort (MAUCO) in Chile. METHODS: This prospective study used the information of individuals, aged 38 to 74 years, excluding those with depression at baseline. The number of remaining teeth at baseline was determined in four groups: "20 or more teeth", "10 to 19 teeth", "1 to 9 teeth" and "no natural teeth". Depression was measured through the PHQ-9. Logistic regression was performed to calculate the odds ratios (OR) for incidence depression at both periods of follow-ups, adjusting for age, sex, educational attainment, diabetes mellitus II, and stressful events at follow-up. Also, we performed adjusted multinomial logistic models to analysis the association between the number of remaining teeth and depression severity. RESULTS: In total individuals (n = 3335 at follow 1, n = 2461 at follow 2), all groups have ORs for incident depression above 1 considering 20 or more teeth as reference. In men, those with 10-19 teeth have 2.44 times higher odds of incident depression than those with 20 or more teeth (OR 2.44, CI 95% 1.33-4.50). Edentulous subjects at 4 years follow-up had 2.24 times higher odds of depression than those with more than 20 teeth (OR 2.24 CI 95%1.35-3.72). In women, the ORs (CI 95%) of incident depression were 2.56 (1.50-4.39), 1.56 (1.02-2.40) and 1.27 (0.90-1.81) for "none", "1-9", "10-19" respectively in comparison to the reference group. In edentulous individuals at baseline, the odds for each of the comparisons "mild vs no", "moderate vs no", "moderately severe vs no" and "severe vs no" were above 1, at both follow-ups. CONCLUSION: Individuals with less than 20 teeth in the mouth could had higher odds of incident depression at 2- and 4-years follow-up, with differences between men and women. Also, in our study, edentulism was associated with increased odds of incident depression at 4-years follow-up in women, and with higher levels of severity of depressive symptoms.

Structural determinants explain caries differences among preschool children in Chile's Metropolitan Region.

OBJECTIVE: To estimate the association between Social Determinants of Health (structural and intermediate) and caries indicators in Chile's Metropolitan Region preschool children. METHODS: A multilevel cross-sectional study of Social Determinants of Health (SDH) and caries in children aged 1 to 6 years in Chile's Metropolitan Region was conducted in 2014-2015, with three levels: district, school and child. Caries were assessed by the dmft-index and the prevalence of untreated caries. The structural determinants analyzed were Community Human Development Index (CHDI), urban/rural location, school type, caregiver's education and family income. Poisson multilevel regression models were fit. RESULTS: The sample size was 2,275 children from 40 schools in 13 districts. While the highest CHDI district had an untreated caries prevalence of 17.1% (12.3-22.7%), in the most disadvantaged district it was 53.9% (95% CI 46.0-61.6%). As family income increased, the probability of untreated caries prevalence decreased (PR = 0.9 95% CI 0.8-1.0). Rural districts had an average dmft-index of 7.3 (95% CI 7.2-7.4), while in urban districts, it was 4.4 (95% CI 4.3-4.5). Higher probabilities of untreated caries prevalence (PR = 3.0 95% CI 2.3-3.9) were observed in rural children. Greater probabilities of untreated caries prevalence (PR = 1.3 95% CI 1.1-1.6) and prevalence of caries experience (PR = 1.3 95% CI 1.1-1.5) were observed in children whose caregivers had a secondary educational level. CONCLUSIONS: A strong association was observed between the social determinants of health, specifically the structural ones, and the caries indicators studied in children of the Metropolitan Region of Chile. There were notable differences in caries between districts according to social advantage. Rurality and caregiver's education were the most consistent predictors.

Undergraduate dental students and their potential role in disaster victim identification procedures: A scoping review under a Chilean perspective.

BACKGROUND: A mass fatality incident is an unexpected event that can cause the death of many people, which has motivated careful analysis and development of appropriate strategies for planning and response with all available resources. As these events involve multiple victims, their identities must be confirmed using the highest possible quality standards. Forensic Odontology (FO) has proven to be a scientific resource for disaster victim identification (DVI) procedures; however, it is highly dependent on the proper management not only of material resources but also of human resources. Chile is a country recognised as prone to natural disasters, but an insufficient number of forensic odontologists has been reported. The aim of the study was to review the literature on a dental undergraduate (UG) student's potential value in a DVI process. METHODOLOGY: A scoping review was performed using a specific search strategy in PubMed/Medline, Web of Science, Scopus, SciELO and EBSCO databases. RESULTS: The search identified 27 articles in which the basic dental degree, the necessary training and the need for human resources are variables considered in different priorities by those articles. DISCUSSION: It is vital to assess the local needs of Chile based on its UGs, considering that FO is an underestimated resource that should be included early on in dental curriculums. Furthermore, it should align with public policies to ensure viability and inclusion in standardised protocols. CONCLUSION: Although there is "potential" usage of UG dental students in DVI is not ideal, circumstances will dictate their use. The better trained they are as students, the more valuable their "potential" contribution will be.

Contrasting student and staff perceptions of preclinical-to-clinical transition at a Chilean dental school.

INTRODUCTION: Dental education is a challenging and demanding field of study as students are expected to acquire various competencies to fulfil their professional requirements after graduation. The objective of this study was to investigate and compare dental students' and clinical staff instructors' perceptions of the preclinical-to-clinical transition training at a Dental School in Santiago, Chile. MATERIAL AND METHODS: Two questionnaires containing 11 quantitative and one qualitative item were developed to assess our year three, four and five (n = 244) dental undergraduate students' challenges when they begin treating patients, and clinical staff (n = 78) perceptions of the preparedness to treat patients of the same students. Both questionnaires were voluntarily and anonymously implemented eight weeks after the beginning of the 2019 academic year. Responses were analysed using a Chi-squared test for each quantitative question, while qualitative comments were studied to form themes and dimensions. RESULTS: A total of 234 (96%) students and 60 (77%) instructors completed their respective questionnaire. There were considerable variations between students in the different years of the programme, as well as between students and staff members. Students and instructors felt the former had enough knowledge to treat patients though it was difficult for them to apply it in clinical practice. Again, both believed they could communicate with patients, but third year students asked for more training on this. Regarding practical skills, fourth- and fifth-year students felt prepared but not third year students, who preferred to work in pairs with senior students, a preference that was shared by the instructors. All student groups asked clinical staff to provide more frequent, constructive and consistent feedback and felt that the difference between simulation and clinical environments and the amount of clinical work to fulfil clinical requirements made them feel stressed. Another mentioned stressor was students' low self-confidence when working with patients. Among the requested improvements, students requested better training on how the dental clinic works to save time. CONCLUSIONS: Preclinical-to-clinical transition training presents several challenges. Some of the problems highlighted by both students and clinical staff members persisted with the transition after three, four and even five years of training, which needs to be addressed.

Odontogenic tumours in a Chilean population: a retrospective study of 544 cases based on 2022 WHO classification.

BACKGROUND: Odontogenic tumours are infrequent lesions. Studies on the frequency of odontogenic tumours from Latin America are scarce. This work aimed to determine the relative frequency of odontogenic tumours in a Chilean population using the 2022 World Health Organization classification. MATERIAL AND METHODS: This is a case series retrospective study. We reviewed 35,530 samples from 1975 to 2022 from the Oral Pathology Referral Institute and the Pathological Anatomy Service, Faculty of Dentistry, University of Chile. We utilized the 2022 World Health Organization classification for histological typification. RESULTS: According to 2022 World Health Organization classification, 544 odontogenic tumours were confirmed. The most frequent odontogenic tumours were: odontoma (n=241; 44.3%), ameloblastoma (n=109; 20.0%) and cemento-ossifying fibroma (n=71; 13.1%). Benign odontogenic tumours corresponded to 538 cases (98.9%) and malignant tumours were only six cases (1.1%). CONCLUSIONS: In our population, odontoma was the most frequent odontogenic tumour followed by ameloblastoma and cemento-ossifying fibroma. Malignant odontogenic tumours were very rare. The results of this study are similar to reports from America, but there are some differences concerning the data from Africa and Asia.

MMP-9 Levels in the Gingival Crevicular Fluid of Chilean Rosacea Patients.

Rosacea is a chronic inflammatory skin disease whose prevalence rates remain unknown in Chile. Laboratory benchmark testing for this disease is not useful, therefore, we aimed to evaluate the gingival crevicular fluid (GCF) levels of extracellular metalloproteinases (MMP)-2 and MMP-9 as novel rosacea biomarkers. We designed a cross-sectional study with a control group. Participants were systemically healthy adults (n = 20) and persons with rosacea (n = 18). We performed a periodontal evaluation and collected gingival crevicular fluid to measure MMP-2 and MMP-9 levels. Analysis showed mean and standard deviation of MMP-9 concentrations in the GCF for patients with rosacea was 764.52 ± 569.83 pg/mL; for healthy patients, it was 260.69 ± 170.43 pg/mL (p < 0.05). The diagnosis of rosacea was responsible for the levels of MMP-9 in the GCF (p < 0.05), as opposed to periodontitis, smoking, and age (p > 0.05). The Area under ROC for MMP-9 was 0.869 (95%, C.I: 0.719−0.956), with a sensitivity of 72.22% and specificity of 81.58% for the diagnosis of rosacea. We conclude that the quantification of MMP-9 in the GCF could be used as a biomarker of rosacea. Also, rosacea was responsible for increasing the levels of MMP-9 in the GCF independent of periodontal status.

The environmental geochemical baseline, background and sources of metal and metalloids present in urban, peri-urban and rural soils in the O´Higgins region, Chile.

The importance of environmental geochemistry baseline in soils of O´Higgins Region, Chile, since it hosts in its eastern area one of the major Cu-Mo producing mines in the country, is to establish and explain relationships between the chemical compositions of the Earth's surface and potential contaminants sources such as mining industry, agriculture and urban activity. A total of 109 samples of urban, peri-urban and rural soils were analyzed with X-ray fluorescence to determine most of the elemental concentrations analyzed. The C and S analyses were performed with the high-temperature combustion method, and a MERCUR mercury analyzer was used for Hg. The study shows that the distribution patterns for most major elements and some trace elements are controlled by the lithologic substrate. This study identified areas with metals and metalloids in high concentrations, which are a risk to the environment and health according to established international regulations. Some of these components correspond to Cu (2500 ppm), Mo (26,5 ppm), As (134,6 ppm), Cr (206.6 ppm), Hg (0.2 ppm), Ni (26.4 ppm), Pb (61.7 ppm), V (227,2 ppm) and Zn (180.3 ppm). Through an elementary association analysis, most of these elements resulted from extractive activities of Cu, metal alloys and oil combustion. It was also possible to trace the use of fertilizers and pesticides in agricultural soils, as well as the combustion of oil related to vehicles in the study area. This information is relevant to implement environmental management strategies to control possible exposure to toxic compounds to human health.

The Chile Biliary Longitudinal Study: A Gallstone Cohort.

Gallbladder cancer (GBC) is a highly fatal cancer that can be cured through cholecystectomy if identified early. The presence of gallstones is the primary risk factor for GBC, but few people with gallstones develop GBC. A key question is what drives the development of GBC among persons with gallstones. We initiated the Chile Biliary Longitudinal Study (Chile BiLS) to address this question. From 2016 to 2019, Chile BiLS enrolled 4,726 women aged 50-74 years with ultrasound-detected gallstones from southern-central Chile, accounting for an estimated 36% of eligible women with gallstones in the study area. The median age was 59 years; 25% of the women were Amerindian (Mapuche), 60% were obese, 25% had diabetes, and 6% had cardiovascular disease. Participants will be followed for gallbladder dysplasia or cancer for 6 years. As of April 30, 2020, over 91% of those eligible completed the year 2 follow-up visit. Data being collected include epidemiologic and sociodemographic information, anthropometric measurements, blood pressure, and tooth counts. Biosamples being taken include baseline plasma, buffy coat, red blood cells, serum, blood clot from serum, and PAXgene whole blood (PreAnalytiX GmbH, Hombrechtikon, Switzerland). Complete gallbladder sampling is conducted for most participants undergoing cholecystectomy. The Chile BiLS cohort study will increase our understanding of GBC etiology and could identify potential risk stratification and early detection strategies in high-risk areas.

The number of species of degus (genus Octodon) is currently underestimated: An appraisal of species limits and their phylogenetic relationships (Rodentia: Hystricomorpha: Octodontidae).

As currently understood, the genus Octodon contains five species degus, lunatus, bridgesii, pacificus, and ricardojeda. Previous phylogenetic studies suggest that genus specific diversity is underestimated. In order to evaluate the taxonomic diversity of Octodon, we implemented unilocus (cytochrome-b) and multilocus (cytochrome-b + 4 nuclear genes) species delimitation methods. Octodon degus was recovered as a sister of the other species of the genus. The unilocus bGMYC and mPTP methods, based on cytochrome-b sequences, delimits 11 and 7 candidate species respectively, and both methods fail to recognize O. pacificus from O. ricardojeda. Results of the multilocus analysis (BPP) vary as a function of the dataset used. When the five genes are used 11 species are delimited, while eight species are delimited when only the nuclear genes are used. Octodon bridgesii is shown as comprising at least two species (one on the Pacific coast and the typical form found on the Andean slopes), while O. ricardojeda may comprise two species (one on the Chilean side of the Andes and the other in Argentina). Likewise, both multilocus matrices recover O. pacificus as a distinct species. This shows that species diversity of Octodon is underestimated. Remarkably, many of the delimited species based on genetic data are morphologically differentiated in cranio-dental characteristics. However, a pair of species has not achieved morphological differentiation, being cryptic species. Finally, the incongruence between mitochondrial and nuclear phylogenies suggests that processes such as incomplete lineage sorting and/or introgression have been present during the radiation of the genus.

Assessment of bullet holes through the analysis of mushroom-shaped morphology in synthetic fibres: analysis of six cases.

Textiles damage analysis is a very valuable tool in forensic investigations. However, to date, very little research has been carried out to understand the impact of bullet causing damages to clothing. According to the review of the most recent scientific papers, the frictional heating and crushing action of a bullet passing through synthetic fibres cause a unique transformation in their ends called mushroom-shaped morphology. In this study, the textile remains of six individuals executed during the first decade of the Chilean military dictatorship period (1973-1990) were analysed. The purpose was to examine their clothing in order to describe the fibre defects in the bullet holes. The fibres were directly observed using two different models of stereomicroscopy (MZ16A and EZ4D, Leica Microsystem Ltd., Wetzlar, Germany) and through a combination of transmitted, oblique and co-axial illumination (with Leica DFC500 Digital Camera), at × 230 and at a resolution of up to 840 Lp/mm. The mushroom-shaped morphology, along with rupturing of yarns, fibrillation or splitting of fibres, was observed in the bullet holes. Although the mushroom-shaped is a useful pattern for bullet hole identification in synthetic fibres, further research needs to be performed for developing a sounder interpretational framework of this type of forensic evidence.

Electroanalytical overview: the pungency of chile and chilli products determined via the sensing of capsaicinoids.

When you bite into a chile pepper or eat food containing chile (chilli), one might feel heat, or other associated feelings, some good such as the release of endorphins, and some bad. The heat, or pungency, and related feelings from eating chile peppers are the result of their chemical composition, i.e. the concentrations of capsaicinoids. The major components are capsaicin and dihydrocapsaicin, which occur in chiles in the ratio of 6 : 4. Other capsaicinoids occur in smaller concentrations and are known as the "minor" capsaicinoids. Wilbur L. Scoville in 1912 created an organoleptic test, now known as the Scoville scale, which asked a panel of tasters to state when an increasingly dilute solution of the chile pepper in alcohol no longer burned the mouth. Following the Scoville scale, a plethora of analytical techniques later followed. In this overview, we explore the endeavours directed to the development of electrochemical-based sensors for the determination of capsaicin and related compounds, starting from their use in hyphenated laboratory set-ups to their modern use as stand-alone electroanalytical sensors. The latter have the advantage of providing a rapid and sensitive methodology that has the potential to be translated in the field; future trends and issues to be overcome are consequently suggested.