Search

Background: The status of the regional lymph node basin is of prognostic importance in patients with melanoma, making the performance of sentinel lymph node biopsies (SLNBs) a key component of patient care management, particularly with the advent of immunotherapy for adjuvant treatment. The primary goal of our study was to assess the false-negative rate of SLNBs among patients with melanoma. Methods: We conducted a retrospective review of patients with melanoma undergoing SLNB by a single surgeon between Jan. 1, 2005, and Dec. 31, 2020. We extracted and cross-referenced patient demographic and pathologic information. Results: During the study period, 501 patients underwent an SLNB. Of these, 97 (19.4%) patients had pathologically positive sentinel lymph nodes and 404 (80.6%) patients had negative results. The latter were subject to further review; 84 (20.8%) patients subsequently developed recurrence, with 25 (6.2%) recurrences within the primary nodal basin. Isolated regional recurrence occurred in 11 (2.7%) patients and conjunction with a false-negative rate was 10.2%. Unadjusted recurrence rates were similar across each lymph node basin, including the axilla (2.7%), groin (3.6%), and neck (1.4%). Conclusion: The false-negative SLNB rate was 10.2% for isolated regional recurrences. These findings need to be considered in the era of using adjuvant systemic therapy for patients with melanoma. Contexte: L' tat du bassin ganglionnaire r gional rev t une importance pronostique chez les personnes atteintes de m lanome, ce qui rend les biopsies des ganglions sentinelles (BGS) essentielles la prise en charge de la maladie, particuli rement depuis l'av nement de l'immunoth rapie en traitement adjuvant. Le principal objectif de notre tude tait d' valuer le taux de r sultats faussement n gatifs des BGS dans les cas de m lanome. M thodes: Nous avons proc d une revue r trospective des cas de m lanome soumis des BGS effectu es par 1 seul membre de l' quipe de chirurgie entre le 1 (er) janvier 2005 et le 31 d cembre 2020. Nous avons extrait et recoup les donn es d mographiques et anatomopathologiques. R sultats: Pendant la dur e de l' tude, 501 personnes ont subi des BGS. Parmi elles, 97 (19,4%) pr sentaient des ganglions sentinelles positifs la biopsie et 404 (80,6%) avaient des r sultats n gatifs. Ce dernier groupe a t soumis un examen plus approfondi; 84 (20,8%) ont par la suite pr sent des r cidives, dont 25 (6,2%) l'int rieur du bassin ganglionnaire primitif. Des r cidives r gionales isol es sont survenues chez 11 (2,7%) personnes et le recoupement avec le taux de r sultats faussement n gatifs a t de 10,2%. Les taux de r cidives non ajust s ont t similaires peu importe les bassins ganglionnaires, y compris axillaires (2,7%), inguinaux (3,6%) et cervicaux (1,4%). Conclusion: Le taux de r sultats faussement n gatifs des BGS a t de 10,2% dans le cas des r cidives r gionales isol es. Il faut interpr ter ces r sultats en tenant compte du fait qu'ils ont t recueillis une poque o les malades atteints de m lanome taient trait s par chimioth rapie adjuvante., The status of the regional lymph node basin is of prognostic significance in patients with melanoma, making sentinel lymph node biopsy (SLNB) a key component of patient care management. Although [...]

High-resolution topographic modeling has become more accessible due to the development of structure from motion (SfM)-image-matching algorithms in digital photogrammetry. Large archival databases of historical aerial photographs are available in university, public, and government libraries, commonly as paper copies. The photographs can be in poor condition (i.e., deformed by humidity, scratched, or annotated). In addition, the negatives, as well as metadata, may be missing. Processing such photographs using classic stereo-photogrammetry is difficult and, in many instances, impossible. SfM can be applied to these photosets to access the valuable archive of geomorphic changes over the past century. In this paper, we illustrate the utility of the SfM technique using 568 digitized vertical aerial photographs of Mount Meager volcano, located in southwestern British Columbia, Canada. We use the aerial photographs, which span the period from 1947 to 2006, to track glaciers and glacier-landslide interactions on the volcano. Over this period, glaciers have thinned and retreated, interrupted by minor advances in the 1960s and 1970s. Landslides are frequent on the volcano and contribute to debris cover on the glaciers affecting the ablation process. SfM processing of the aerial photographs allowed us to unlock geomorphic information and reconstruct landscape change that would otherwise have been impossible. The results from SfM provide a visually effective way of presenting landscape change to a broad public audience, as a form of virtual geoheritage. The approach can thus be broadly applied in scientific and professional practices for improving land planning and hazard management. Key words: historical aerial photographs, structure from motion, glacier change, landslides, debris-covered glaciers. La modelisation topographique de haute resolution est devenue plus accessible en raison du developpement d'algorithmes de jumelage d'images de type << structure from motion >> (SfM, structure acquise a partir d'un mouvement) en photogrammetrie numerique. D'imposantes bases de donnees d'archives de photographies aeriennes sont disponibles dans les bibliotheques universitaires, publiques et gouvernementales, generalement en version papier. Ces photographies peuvent etre en mauvais etat (c.-a-d., deformees par l'humidite, egratignees ou annotees). En outre, des negatifs, ainsi que des metadonnees, peuvent manquer a l'appel. Le traitement de telles photographies par stereophoto-grammetrie classique est difficile, voire impossible dans bien des cas. La SfM peut etre appliquee a ses ensembles de photos pour acceder a l'important registre de changements geomorphologiques durant le siecle passe qu'ils renferment. Nous illustrons l'utilisation de la methode SfM en utilisant 568 photographies aeriennes verticales numerisees du volcan du mont Meager, dans le sud-ouest de la Colombie-Britannique (Canada). Nous utilisons les photographies aeriennes, qui couvrent la periode de 1947 a 2006, pour suivre les glaciers et les interactions entre glaciers et glissements de terrain sur le volcan. Cette periode est marquee par l'amincissement et le retrait des glaciers, interrompus par des avancees mineures dans les annees 1960 et 1970. Les glissements de terrain sont frequents sur le volcan et participent a l'accumulation d'un couvert de debris sur les glaciers qui influence le processus d'ablation. Le traitement SfM des photographies aeriennes nous a permis d'extraire de l'information geomorphologique et de reconstituer les changements du paysage, ce qui n'aurait pas ete possible autrement. Les resultats de SfM offrent un moyen visuellement efficace de presenter des modifications du paysage au grand public, comme geopatrimoine virtuel. L'approche peut ainsi etre appliquee largement dans les domaines scientifique et professionnel pour ameliorer l'amenagement du territoire et la gestion des risques. [Traduit par la Redaction] Mots-cles : photographies aeriennes passees, << structure from motion >>, modification de glaciers, glissements de terrain, glaciers couverts de debris., Introduction Reconstructions of geomorphic change over time are fundamental in many landform and natural hazard studies. Such landscape reconstructions are essential for following the evolution of features that might cause [...]

The coronavirus disease 2019 (COVID-19) pandemic has affected children's risk of violence in their homes, communities and online, and has compromised the ability of child protection systems to promptly detect and respond to cases of violence. However, the need to strengthen violence prevention and response services has received insufficient attention in national and global pandemic response and mitigation strategies. In this paper, we summarize the growing body of evidence on the links between the pandemic and violence against children. Drawing on the World Health Organization's INSPIRE framework to end violence against children, we illustrate how the pandemic is affecting prevention and response efforts. For each of the seven INSPIRE strategies we identify how responses to the pandemic have changed children's risk of violence. We offer ideas for how governments, policy-makers, and international and civil society organizations can address violence in the context of a protracted COVID-19 crisis. We conclude by highlighting how the current pandemic offers opportunities to improve existing child protection systems to address violence against children. We suggest enhanced multisectoral coordination across the health, education, law enforcement, housing, child and social protection sectors. Actions need to prioritize the primary prevention of violence and promote the central role of children and adolescents in decision-making and programme design processes. Finally, we stress the continued need for better data and evidence to inform violence prevention and response strategies that can be effective during and beyond the COVID-19 pandemic. La pandemie de maladie a coronavirus 2019 (COVID-19) a eu un impact sur le risque de violence a l'egard des enfants a domicile, au sein de leur communaute et en ligne. Elle a egalement empeche les systemes de protection de l'enfance d'identifier rapidement les situations de ce typeetd'y reagirdesque possible. Pourtant, la necessitede renforcer les services de prevention et d'action en la matiere n'a pas ete suffisamment prise en compte dans les strategies nationales et internationales d'intervention et d'attenuation des effets de la pandemie. Le present document reprend l'accumulation de preuves confirmant les liens entre pandemie et violence a l'egard des enfants. En nous inspirant du cadre INSPIRE de l'Organisation mondiale de la Sante visant a mettre fin a la violence a l'encontre des enfants, nous illustrons la facon dont la pandemie affecte les efforts de prevention et d'action. Pour chacune des sept strategies INSPIRE, nous determinons comment les mesures de lutte contre la pandemie ont influence le risque de violence envers les enfants. Nous formulons des pistes pour que les gouvernements, les legislateurs, les institutions Internationales et les organisations de la societe civile puissent remedier a cette violence dans un contexte de crise prolongee due a la COVID-19. En guise de conclusion, nous mettons en lumiere les opportunites qu'offre la pandemie actuelle d'ameliorer les systemes existants de protection de l'enfance pour mieux combattre la violence envers les enfants. Nous suggerons d'accroitre la collaboration entre les secteurs de la sante, de l'education, du maintien de l'ordre, du logement, des droits de l'enfant et de la protection sociale. Les actions entreprises doivent sefocaliser sur la prevention primaire de la violence et promouvoir le role central des enfants et adolescents dans les processus de conception de programmes et de prise de decisions. Enfin, nous soulignons le besoin permanent de donnees et de preuves fiables pour orienter les strategies de prevention et d'intervention face a la violence, afin degarantir leur efficacite pendantetapres la pandemie de COVID-19. La pandemia de la enfermedad porcoronavirus (COVID-19) ha afectado al riesgo de violencia infantil que sufren los ninos en sus hogares, comunidades y en linea, y ha puesto en peligro la capacidad de los sistemas de proteccion infantil para detectar y responder rapidamente a los casos de violencia. Sin embargo, la necesidad de reforzar los servicios de prevencion y respuesta a la violencia no ha recibido suficiente atencion en las estrategias nacionales y mundiales de respuesta y mitigacion de la pandemia. En este documento, resumimos el creciente conjunto de pruebas sobre los vinculos entre la pandemia y la violencia infantil. Basandonos en el marco INSPIRE de la Organizacion Mundial de la Salud para poner fin a la violencia Infantil, ilustramos como la pandemia esta afectando a los esfuerzos de prevencion y respuesta. Para cada una de las siete estrategias de INSPIRE, identificamos como las respuestas a la pandemia han cambiado el riesgo de violencia infantil. Ofrecemos ideas sobre como los gobiernos, los responsables politicos y las organizaciones internacionales y de la sociedad civil pueden abordar la violencia en el contexto de una crisis prolongada de COVID-19. Concluimos destacando como la pandemia actual ofrece oportunidades para mejorar los sistemas de proteccion infantil existentes para abordar este tipo de violencia. Sugerimos una mayor coordinacion multisectorial en los sectores de la salud, la educacion, la aplicacion de la ley, la vivienda y la proteccion social infantil. Las acciones deben priorizar la prevencion primaria de la violencia y promover el papel central de los ninos y adolescentes en los procesos de toma de decisiones y en el diseno de programas. Por ultimo, subrayamos la necesidad permanente de contar con mejores datos y pruebas para fundamentar las estrategias de prevencion y respuesta a la violencia que puedan ser eficaces durante la pandemia de COVID-19 y seguir vigentes cuando esta pase. [phrase omitted], Introduction Throughout the coronavirus disease 2019 (COVID-19) pandemic, children have often been referred to as silent spreaders, low-risk or invisible carriers of the disease. These descriptions negate the well-documented adverse [...]

Introduction: Daily and event-driven PrEP are both efficacious in reducing the risk for HIV infection. However, the practice of event-driven PrEP (edPrEP) is less well studied, in particular when provided as an alternative to daily PrEP. We studied regimen preferences and switches, and sexually transmitted infection (STI) incidence. Methods: We analysed pooled data from two prospective cohort studies among MSM: Be-PrEP-ared, Belgium and AMPrEP, the Netherlands. In both projects, participants could choose between daily and edPrEP at three-monthly study visits, when they were also screened for sexually transmitted infections including hepatitis C (HCV). We assessed the proportion choosing each regimen, and the determinants of choosing edPrEP at baseline. Additionally, we compared the incidence rates (IRs) of HCV, syphilis and chlamydia or gonorrhoea between regimens using Poisson regression. The study period was from 3 August 2015 until 24 September 2018. Results and discussion: We included 571 MSM, of whom 148 (25.9%) chose edPrEP at baseline. 31.7% of participants switched regimen at least once. After 28 months, 23.5% used edPrEP. Older participants (adjusted odds ratio (aOR) = 1.38 per 10 years, 95% confidence interval (CI) = 1.15 to 1.64) and those unemployed (aOR = 1.68, 95% CI = 1.03 to 1.75) were more likely to initially choose edPrEP. IR of HCV and syphilis did not differ between regimens, but the IR of chlamydia/gonorrhoea was higher among daily users (adjusted incidence rate ratio = 1.61, 95% CI = 1.35 to 1.94). Conclusions: A quarter of participants chose edPrEP at baseline and at 28 months this proportion was similar. Although the IR of HCV and syphilis were similar in the two regimens, the lower incidence of chlamydia and gonorrhoea among edPrEP users may suggest that less frequent STI testing of this group could be considered. Keywords: pre-exposure prophylaxis; sexually transmitted infections; event-driven PrEP; syphilis; men who have sex with men; HIV prevention & control, 1 | INTRODUCTION Oral pre-exposure prophylaxis (PrEP) with tenofovir disoproxil fumarate and emtricitabine, is efficacious for human immunodeficiency virus (HIV) prevention, provided that it is taken correctly [1-3]. Among men [...]

Introduction: Event-driven pre-exposure prophylaxis (edPrEP) with oral tenofovir disoproxil fumarate (TDF)/emtricitabine (FTC) is highly effective for preventing HIV acquisition in men who have sex with men (MSM) and is preferred over daily PrEP by some MSM. However, it is largely unknown how well MSM adhere to edPrEP. We then aimed to assess PrEP protection during CAS among MSM using edPrEP and participating in the Amsterdam PrEP demonstration project (AMPrEP). Methods: We analysed data from participants enrolled in AMPrEP who were taking edPrEP. We measured adherence through (1) a mobile application in which sexual behaviour and PrEP-use were recorded daily, (2) three-monthly self-completed questionnaires and (3) dried blood spot (DBS) samples collected around six, twelve and twenty-four months after PrEP initiation. We assessed the proportion of days with condomless anal sex (CAS) acts that were protected by PrEP, per partner type (i.e. steady partners, known casual partners, unknown casual partners), and the proportion of three-month periods during which PrEP was correctly used. Intracellular TFV-diphosphate (TFV-DP) concentrations were determined from DBS. Good adherence was defined as at least one tablet before and one tablet within 48 hours after a CAS act. Results: Between 11 September 2015 and 6 October 2019, 182 of 376 MSM (48.4%) used edPrEP for at least one three-month period. Of the 8224 CAS days that were reported in the app during edPrEP-use, we observed good protection for most CAS days involving steady partners (n = 1625/2455, 66.9%), known casual partners (n = 3216/3472, 92.6%) and unknown casual partners (n = 2074/2297, 90.3%). Men reported consistently correct PrEP-use in 851 (81.4%) of the 1046 three-month periods of edPrEP-use. The median TFV-DP concentration was 591 fmol/sample (interquartile range = 270 to 896). Conclusions: Adherence to edPrEP was high as determined from the online app and questionnaire. DBS measurements were consistent with two to three tablets per week on average. Keywords: HIV; Pre-exposure prophylaxis; On-demand PrEP; medication adherence; HIV prevention and control; men who have sex with men, 1 | INTRODUCTION Pre-exposure prophylaxis (PrEP) has been proven to be highly effective against the acquisition of human immunodeficiency virus (HIV) [1,2]. The World Health Organization has therefore recommended that [...]

Background: Patients who undergo vascular surgery are burdened by high early readmission rates. We examined the frequency and cause of early readmissions after elective and emergent admission to the vascular surgery service at our institution to identify modifiable targets for quality improvement. Methods: Over a 5-year period, all patients admitted and readmitted to the vascular surgery service were identified. Medical records were then individually reviewed to identify baseline characteristics from the index admission and the most responsible diagnosis for readmission within 28 days of discharge. Results: Of a total of 3324 patients, 421 (12.7%) were readmitted to our institution within 28 days of discharge. Forty-seven were found to have more than 1 readmission following their index admission. The readmission rate ranged from 11.8% to 14.1% over the 5-year study period, resulting in an average readmission rate of 12.7%. There were similar rates for men (12.9%) and women (12.3%). Of the readmitted cases, 236 (63.1%) were unplanned readmissions. The most common diagnoses for unplanned readmissions were worsening of peripheral arterial disease status including complications related to peripheral bypass graft (30.9%), surgical site infections (15.3%) and nonsurgical infections (14.8%). Conclusion: To reduce readmission rates effectively, institutions must identify high-risk patients. In our study cohort, the most frequent pathology resulting in readmission was peripheral arterial disease. The most frequent preventable reason for readmission was surgical site infection. Interventions focused on early assessment of clinical status and wounds in addition to avoidance of infectious complications could help reduce readmission rates. Preventive resources can be efficiently targeted by focusing on subgroups at risk for readmission. Contexte: Les patients soumis a une chirurgie vasculaire presentent malheureusement un taux eleve de readmission precoce. Nous avons analyse la frequence et les causes de readmission precoce apres une admission urgente ou non urgente au service de chirurgie vasculaire afin d'identifier les facteurs modifiables en vue d'ameliorer la qualite des soins. Methodes: Sur une periode de 5 ans, tous les patients admis, puis readmis au service de chirurgie vasculaire ont ete identifies. On a ensuite passe en revue individuellement les dossiers medicaux pour relever les caracteristiques de base a l'admission initiale et le diagnostic ayant le plus probablement justifie la readmission dans les 28 jours suivant le conge. Resultats: Sur un total de 3324 patients, 421 (12,7%) ont ete readmis a notre etablissement dans les 28 jours suivant leur conge. Quarante-sept ont ete readmis plus d'une fois apres leur hospitalisation initiale. Le taux de readmission a varie de 11,8% a 14,1% pendant la periode de 5 ans de l'etude, le taux moyen de readmission etant de 12,7%. Les taux etaient similaires chez les hommes (12,9%) et les femmes (12,3%). Parmi les cas readmis, 236 (63,1%) etaient imprevus. Les diagnostics ayant le plus souvent justifie une readmission imprevue etaient aggravation de la maladie arterielle peripherique (y compris complications au niveau de pontages arteriels peripheriques) (30,9%), infection du site operatoire (15,3%) et infections non chirurgicales (14,8%). Conclusion: Pour reduire efficacement les taux de readmission, les etablissements doivent identifier les patients a haut risque. Dans notre cohorte, la pathologie ayant le plus souvent mene a une readmission etait la maladie arterielle peripherique. La raison evitable la plus frequente etait l'infection du site operatoire. Les interventions axees sur une evaluation rapide de l'etat clinique et de l'etat des plaies, ainsi que la prevention des complications infectieuses pourraient contribuer a reduire les taux de readmission. Des mesures preventives pourraient cibler judicieusement les groupes a risque de readmission., Hospital readmission has become a focus of quality improvement initiatives because of the associated burden on patients and the health care system. Many studies have found that unplanned readmissions are [...]

Background School-based violence prevention interventions offer enormous potential to reduce children's experience of violence perpetrated by teachers, but few have been rigorously evaluated globally and, to the best of our knowledge, none in humanitarian settings. We tested whether the EmpaTeach intervention could reduce physical violence from teachers to students in Nyarugusu Refugee Camp, Tanzania. Methods and findings We conducted a 2-arm cluster-randomised controlled trial with parallel assignment. A complete sample of all 27 primary and secondary schools in Nyarugusu Refugee Camp were approached and agreed to participate in the study. Eligible students and teachers participated in cross-sectional baseline, midline, and endline surveys in November/December 2018, May/June 2019, and January/February 2020, respectively. Fourteen schools were randomly assigned to receive a violence prevention intervention targeted at teachers implemented in January-March 2019; 13 formed a wait-list control group. The EmpaTeach intervention used empathy-building exercises and group work to equip teachers with self-regulation, alternative discipline techniques, and classroom management strategies. Allocation was not concealed due to the nature of the intervention. The primary outcome was students' self-reported experience of physical violence from teachers, assessed at midline using a modified version of the ISPCAN Child Abuse Screening Tool-Child Institutional. Secondary outcomes included student reports of emotional violence, depressive symptoms, and school attendance. Analyses were by intention to treat, using generalised estimating equations adjusted for stratification factors. No schools left the study. In total, 1,493 of the 1,866 (80%) randomly sampled students approached for participation took part in the baseline survey; at baseline 54.1% of students reported past-week physical violence from school staff. In total, 1,619 of 1,978 students (81.9%) took part in the midline survey, and 1,617 of 2,032 students (79.6%) participated at endline. Prevalence of past-week violence at midline was not statistically different in intervention (408 of 839 students, 48.6%) and control schools (412 of 777 students, 53.0%; risk ratio = 0.91, 95% CI 0.80 to 1.02, p = 0.106). No effect was detected on secondary outcomes. A camp-wide educational policy change during intervention implementation resulted in 14.7% of teachers in the intervention arm receiving a compressed version of the intervention, but exploratory analyses showed no difference in our primary outcome by school-level adherence to the intervention. Main study limitations included the small number of schools in the camp, which limited statistical power to detect small differences between intervention and control groups. We also did not assess the test-retest reliability of our outcome measures, and interviewers were unmasked to intervention allocation. Conclusions There was no evidence that the EmpaTeach intervention effectively reduced physical violence from teachers towards primary or secondary school students in Nyarugusu Refugee Camp. Further research is needed to develop and test interventions to prevent teacher violence in humanitarian settings. Trial registration clinicaltrials.gov (NCT03745573), Author(s): Camilla Fabbri 1,*, Katherine Rodrigues 2, Baptiste Leurent 1, Elizabeth Allen 1, Mary Qiu 3, Martin Zuakulu 3, Dennis Nombo 2, Michael Kaemingk 4, Alexandra De Filippo 4, Gerard [...]

Author(s): Tim DeVries (corresponding author) [1, 2]; Mark Holzer [3, 4]; Francois Primeau [5] The ocean is the largest sink for anthropogenic carbon dioxide (CO[sub.2] ), having absorbed roughly 40 [...]

Aftershocks are a response to changes in stress generated by large earthquakes and represent the most common observations of the triggering of earthquakes. The maximum magnitude of aftershocks and their temporal decay are well described by empirical laws (such as Bath's law.sup.1 and Omori's law.sup.2), but explaining and forecasting the spatial distribution of aftershocks is more difficult. Coulomb failure stress change.sup.3 is perhaps the most widely used criterion to explain the spatial distributions of aftershocks.sup.4-8, but its applicability has been disputed.sup.9-11. Here we use a deep-learning approach to identify a static-stress-based criterion that forecasts aftershock locations without prior assumptions about fault orientation. We show that a neural network trained on more than 131,000 mainshock-aftershock pairs can predict the locations of aftershocks in an independent test dataset of more than 30,000 mainshock-aftershock pairs more accurately (area under curve of 0.849) than can classic Coulomb failure stress change (area under curve of 0.583). We find that the learned aftershock pattern is physically interpretable: the maximum change in shear stress, the von Mises yield criterion (a scaled version of the second invariant of the deviatoric stress-change tensor) and the sum of the absolute values of the independent components of the stress-change tensor each explain more than 98 per cent of the variance in the neural-network prediction. This machine-learning-driven insight provides improved forecasts of aftershock locations and identifies physical quantities that may control earthquake triggering during the most active part of the seismic cycle.Neural networks trained on data from about 130,000 aftershocks from around 100 large earthquakes improve predictions of the spatial distribution of aftershocks and suggest physical quantities that may control earthquake triggering., Author(s): Phoebe M. R. DeVries [sup.1] [sup.2] , Fernanda Viégas [sup.3] , Martin Wattenberg [sup.3] , Brendan J. Meade [sup.1] Author Affiliations:(1) Department of Earth and Planetary Sciences, Harvard University, [...]

Abstract: Timing of breeding varies among waterfowl species and individuals, with strong effects on reproductive success, and may be related to habitat quality. Here, we analyse the start, span, and [...]