Problem solving, exercises, and explorations in mathematics textbooks: A historical perspective

This paper analyses the tasks proposed in several Portuguese mathematics textbooks, from the 19th to the 21st century. A look at the nature and intended purpose of these tasks raises interesting issues about school mathematics teaching and learning. Has the meaning of terms such as “problem” and “exercise” been always the same? What other terms have been used in textbooks to designate mathematics tasks? What were the reasons for the changes? The analysis of the evolution that occurred in the terminology as well as in the nature of the tasks proposed to the students provides elements to reflect about what the changes that have occurred in mathematics teaching and learning and how some changes are more apparent than real.info:eu-repo/semantics/publishedVersio

Gravitational Pull: A Filmmaker in the Orbit of the Modernist Sun

The massive, still-burning modernist sun exerts a powerful gravitational pull on my filmmaking, setting me in orbit around the modernists in its core. Arcing solar flares of filmic and poetic modernism burst out at me: Maya Deren’s cine-poems, rhythmic editing, elisions of time/space; Ezra Pound’s imagism, T.S. Eliot’s objective correlatives. The form-expanding classical reception of H.D. (Hilda Doolittle) in Helen in Egypt sparks my imagination and experimentation in my film grounded in the Homeric view of Penelope.As I continue my orbit, there are more modernists pulling on me: Alain Resnais with his enigmatic editing structures and entanglements of memory; Michelangelo Antonioni’s emotional color and form present as objective correlatives, which lead me back full circle. One bright solar flare draws me repeatedly to Chris Marker’s La Jetée, in which a powerful image of the past fractures history. As I continue making films informed by and incorporating my receptions of the past, I remain warmed by the modernist sun’s force of attraction

The Safe Zone: Suggestions For Successfully Navigating the Promotion and Tenure Process

In awarding tenure the university expresses its commitment to recognizing and rewarding professional achievement and to assuring academic freedom. In accepting tenure the faculty member expresses a commitment to the academic quality of the institution and enhancing the university’s programs. Toward arriving at an intersection of these interests, and being awarded tenure, it makes good sense for faculty members to develop and employ a roadmap for success. This is especially important given that mind reading is an imperfect form of communication and you wish to communicate clearly with your peer committees and unit administrators. This session will address strategies for faculty to advance, communicate, and navigate along this path

Conserved Patterns in Developmental Processes and Phases, Rather than Genes, Unite the Highly Divergent Bilateria

Bilateria are the predominant clade of animals on Earth. Despite having evolved a wide variety of body plans and developmental modes, they are characterized by common morphological traits. By default, researchers have tried to link clade-specific genes to these traits, thus distinguishing bilaterians from non-bilaterians, by their gene content. Here we argue that it is rather biological processes that unite Bilateria and set them apart from their non-bilaterian sisters, with a less complex body morphology. To test this hypothesis, we compared proteomes of bilaterian and non-bilaterian species in an elaborate computational pipeline, aiming to search for a set of bilaterian-specific genes. Despite the limited confidence in their bilaterian specificity, we nevertheless detected Bilateria-specific functional and developmental patterns in the sub-set of genes conserved in distantly related Bilateria. Using a novel multi-species GO-enrichment method, we determined the functional repertoire of genes that are widely conserved among Bilateria. Analyzing expression profiles in three very distantly related model species-D. melanogaster,D. rerioandC. elegans-we find characteristic peaks at comparable stages of development and a delayed onset of expression in embryos. In particular, the expression of the conserved genes appears to peak at the phylotypic stage of different bilaterian phyla. In summary, our study illustrate how development connects distantly related Bilateria after millions of years of divergence, pointing to processes potentially separating them from non-bilaterians. We argue that evolutionary biologists should return from a purely gene-centric view of evolution and place more focus on analyzing and defining conserved developmental processes and periods

Mobile Applications in Mood Disorders and Mental Health: Systematic Search in Apple App Store and Google Play Store and Review of the Literature

Objectives: The main objective of this work was to explore and characterize the current landscape of mobile applications available to treat mood disorders such as depression, bipolar disorder, and dysthymia. Methods: We developed a tool that makes both the Apple App Store and the Google Play Store searchable using keywords and that facilitates the extraction of basic app information of the search results. All app results were filtered using various inclusion and exclusion criteria. We characterized all resultant applications according to their technical details. Furthermore, we searched for scientific publications on each app’s website and PubMed, to understand whether any of the apps were supported by any type of scientific evidence on their acceptability, validation, use, effectiveness, etc. Results: Thirty apps were identified that fit the inclusion and exclusion criteria. The literature search yielded 27 publications related to the apps. However, these did not exclusively concern mood disorders. 6 were randomized studies and the rest included a protocol, pilot-, feasibility, case-, or qualitative studies, among others. The majority of studies were conducted on relatively small scales and 9 of the 27 studies did not explicitly study the effects of mobile application use on mental wellbeing. Conclusion: While there exists a wealth of mobile applications aimed at the treatment of mental health disorders, including mood disorders, this study showed that only a handful of these are backed by robust scientific evidence. This result uncovers a need for further clinically oriented and systematic validation and testing of such apps

Impact of denosumab on the peripheral skeleton of postmenopausal women with osteoporosis: Bone density, mass, and strength of the radius, and wrist fracture

Objective: The aim of this study was to report the effects of denosumab on radius cortical and trabecular bone density, mass, and strength, and wrist fracture incidence in the FREEDOM (Fracture REduction Evaluation of Denosumab in Osteoporosis every 6 Months) study. Methods: In the FREEDOM study, postmenopausal women with osteoporosis (N = 7,808) received placebo or 60 mg of denosumab every 6 months for 36 months. Radius bone mineral density (BMD), bone mineral content, and strength (polar moment of inertia) were evaluated in two prespecified substudies using dual-energy x-ray absorptiometry (placebo, n = 209; denosumab, n = 232) or quantitative CT (placebo, n = 48; denosumab, n = 62). Prespecified analysis assessed wrist fracture incidence in all FREEDOM participants (placebo, N = 3,906; denosumab, N = 3,902), and post hoc subgroup analyses evaluated those with higher fracture risk (baseline femoral neck T-score ≤−2.5; placebo, N = 1,406; denosumab, N = 1,384). Results: Denosumab significantly increased areal BMD (assessed by dual-energy x-ray absorptiometry) and volumetric BMD, bone mineral content, and polar moment of inertia (assessed by quantitative CT), compared with placebo, in radius cortical and trabecular bone at all time points evaluated (all P < 0.05). Wrist fracture incidence was 2.9% for placebo and 2.5% for denosumab (relative risk reduction, 16%; P = 0.21) on month 36. Participants with a femoral neck T-score of −2.5 or lower were at increased risk for wrist fracture, and denosumab significantly reduced wrist fracture incidence compared with placebo (placebo, 4.0%; denosumab, 2.4%; relative risk reduction, 40%; absolute risk reduction, 1.6%; P = 0.03). Conclusions: Denosumab significantly improves radius bone density, mass, and strength compared with placebo. In higher-risk women, denosumab significantly reduces wrist fracture risk

Assay optimization for molecular detection of Zika virus

To examine the diagnostic performance of real-time reverse transcription (RT)-polymerase chain reaction (PCR) assays for Zika virus detection. We compared seven published real-time RT-PCR assays and two new assays that we have developed. To determine the analytical sensitivity of each assay, we constructed a synthetic universal control ribonucleic acid (uncRNA) containing all of the assays' target regions on one RNA strand and spiked human blood or urine with known quantities of African or Asian Zika virus strains. Viral loads in 33 samples from Zika virus-infected patients were determined by using one of the new assays. Oligonucleotides of the published real-time RT-PCR assays, showed up to 10 potential mismatches with the Asian lineage causing the current outbreak, compared with 0 to 4 mismatches for the new assays. The 95% lower detection limit of the seven most sensitive assays ranged from 2.1 to 12.1 uncRNA copies/reaction. Two assays had lower sensitivities of 17.0 and 1373.3 uncRNA copies/reaction and showed a similar sensitivity when using spiked samples. The mean viral loads in samples from Zika virus-infected patients were 5 × 104 RNA copies/mL of blood and 2 × 104 RNA copies/mL of urine. We provide reagents and updated protocols for Zika virus detection suitable for the current outbreak strains. Some published assays might be unsuitable for Zika virus detection, due to the limited sensitivity and potential incompatibility with some strains. Viral concentrations in the clinical samples were close to the technical detection limit, suggesting that the use of insensitive assays will cause false-negative results. Étudier la performance diagnostique des tests basés sur l'amplification en chaîne par polymérase (PCR) en temps réel après transcription inverse (RT) pour détecter le virus Zika. Nous avons comparé sept tests publiés utilisant la RT-PCR en temps réel et deux nouveaux tests développés par nos soins. Afin de déterminer la sensibilité analytique de chaque test, nous avons conçu un acide ribonucléique synthétique de contrôle universel (ARNcun) contenant toutes les régions ciblées par les tests sur une hélice ARN et enrichi de l’urine ou du sang humain de quantités connues de souches africaines ou asiatiques du virus Zika. Les charges virales dans 33 échantillons provenant de patients infectés par le virus Zika ont été déterminées à l'aide de l'un des nouveaux tests. Les oligonucléotides des tests publiés utilisant la RT-PCR en temps réel ont présenté jusqu'à 10 mauvais appariements potentiels avec la lignée asiatique provoquant l'épidémie actuelle, alors qu'on a constaté de 0 à 4 mauvais appariements dans le cas des nouveaux tests. La limite de détection inférieure à 95% des sept tests les plus sensibles variait de 2,1 à 12,1 copies d'ARNcun/réaction. Deux tests présentaient des sensibilités plus basses de 17,0 et 1373,3 copies d'ARNcun/réaction et montraient une sensibilité similaire lorsque des échantillons enrichis étaient utilisés. Les charges virales moyennes dans les échantillons provenant de patients infectés par le virus Zika étaient de 5 × 104 copies d'ARN/mL de sang et de 2 × 104 copies d'ARN/mL d'urine. Nous proposons pour détecter le virus Zika des réactifs et des protocoles actualisés, adaptés aux souches responsables de la flambée actuelle. Tous les tests publiés ne permettent pas de détecter le virus Zika en raison d'une sensibilité limitée et d'une incompatibilité potentielle avec certaines souches. Les concentrations virales dans les échantillons cliniques étaient proches de la limite de détection technique, ce qui laisse penser que l'utilisation de tests insensibles donnera des résultats faussement négatifs. Examinar el rendimiento del diagnóstico de las pruebas de reacción en cadena de la polimerasa de transcriptasa inversa (RT-PCR) en tiempo real para la detección del virus de Zika. Se compararon siete pruebas de RT-PCR en tiempo real publicadas y dos pruebas nuevas que se han desarrollado. Con el fin de determinar la sensibilidad analítica de cada prueba, se construyó un ácido ribonucleico sintético de control universal (uncRNA) que contenía todas las regiones objetivo de las pruebas en una hebra de RNA y se añadió a sangre u orina humana con cantidades conocidas de cepas de virus de Zika de Asia o África. Se determinaron las cargas víricas en 33 muestras procedentes de pacientes infectados por el virus de Zika a través de una de las pruebas nuevas. Los oligonucleótidos de las pruebas de RT-PCR en tiempo real publicadas mostraron hasta 10 posibles discordancias con el linaje de Asia causante de los brotes actuales, en comparación con 0 de 4 discordancias en el caso de las pruebas nuevas. El límite de detección inferior del 95% de las siete pruebas más sensibles abarcó de 2,1 a 12,1 copias/reacción de uncRNA. Dos pruebas mostraron sensibilidades inferiores de 17,0 y 1373,3 copias/reacción de uncRNA y presentaron una sensibilidad similar al usar muestras infectadas. Las cargas víricas medias en las muestras procedentes de pacientes infectados por el virus de Zika fueron de 5 × 104 copias de RNA/mL de sangre y de 2 × 104 copias de RNA/ml de orina. Se proporcionan reactivos y protocolos actualizados para la detección adecuada del virus de Zika en el caso de las cepas de brotes actuales. Algunas pruebas publicadas pueden no ser adecuadas para la detección del virus de Zika, debido a la limitada sensibilidad y a la posible incompatibilidad con algunas cepas. Las concentraciones víricas en las muestras clínicas se acercaron al límite de detección técnico, lo que sugería que el uso de pruebas intensivas causaría resultados falsos negativos. دراسة الأداء التشخيصي لاختبارات تفاعل البوليميراز المتسلسل اللحظي (PCR) مع إنزيم النسخ العكسي (RT) لاكتشاف الإصابة بفيروس زيكا. قمنا بإجراء مقارنة بين سبعة اختبارات منشورة لتفاعل البوليميراز المتسلسل اللحظي مع إنزيم النسخ العكسي (RT‑PCR) واختبارين جديدين تم إعدادهما من جانبنا. ولتحديد الحساسية التحليلية لكل اختبار، قمنا بتكوين الحمض النووي الريبوزي الاصطناعي للمكافحة العامة (uncRNA) والذي يحتوي على جميع المناطق المستهدفة في الاختبار في شريط RNA واحد ويحتوي على مؤشرات للدم أو البول البشري الذي يحتوي على كميات معروفة من سلالات فيروس زيكا في منطقة أفريقيا أو آسيا. وتم تحديد الحمولات الفيروسية في 33 عينة صادرة من مرضى مصابين بفيروس زيكا باستخدام أحد الاختبارات الجديدة. أظهرت الأوليغونيكليوتيدات الخاصة باختبارات تفاعل البوليميراز المتسلسل اللحظي مع إنزيم النسخ العكسي ما يصل إلى 10 حالات محتملة من عدم التطابق مع السلالة الآسيوية المسببة للعدوى الحالية، بالمقارنة مع حالات عدم التطابق بالنسبة للاختبارات الجديدة بمعدل 0 إلى 4. تراوح حد الاكتشاف المنخفض بنسبة 95‏% في الاختبارات السبعة الأكثر حساسية من 2.1 إلى 12.1 من نسخ سلالات uncRNA لتفاعل كل حالة. وُجد لدى اثنين من الاختبارات درجات منخفضة من الحساسية بمقدار 17.0 و1373.3 لنسخ سلالات uncRNA لتفاعل كل حالة وأظهرت وجود درجة حساسية مماثلة عند استخدام عينات المؤشرات. بلغ متوسط الحمولات الفيروسية في العينات الصادرة عن المرضى المصابين بفيروس زيكا 5 × 10 4 نسخ من RNA لكل ملليلتر من الدم و 2 × 10 4 نسخ من RNA لكل ملليلتر من البول. نحن نوفر الكاشفات وأحدث البروتوكولات لاكتشاف فيروس زيكا والتي تناسب سلالات العدوى الحالية. وقد تكون بعض الاختبارات المنشورة غير مناسبة لاكتشاف فيروس زيكا نظرًا لوجود درجة محدودة من الحساسية واحتمالية عدم توافقها مع بعض السلالات. كانت نسب تركيز الفيروسات في العينات التحليلية قريبة من حد الاكتشاف التقني، مما يشير إلى أن استخدام الاختبارات التي تفتقد إلى الحساسية سيؤدي إلى إصدار نتائج خاطئة وسلبية. 旨在检查针对寨卡病毒检测的实时逆转录 (RT)-聚合酶链反应 (PCR) 试验的诊断性能。. 我们比较了 7 种公布的实时 RT-PCR 试验和我们开发的两种新试验。 为了确定各种试验的分析灵敏度，我们构建了在一个 RNA 链上包含所有试验目标区域的合成通用对照核糖核酸 (uncRNA) 以及带有已知数量的非洲或亚洲寨卡病毒株的加标人体血液或尿液。 通过使用一种新的试验测定 33 个寨卡病毒感染患者样本的病毒载量。. 已公布的实时 RT-PCR 试验的寡核苷酸，显示出与亚洲血统潜在的失配率高达 10，相比之下，新试验的失配率为 0 至 4。 七种最敏感试验的 95% 检测下限范围为 2.1 至 12.1 uncRNA 拷贝/反应。 两个试验中 17.0 和 1373.3 uncRNA 复制/反应的灵敏度较低，使用加标样本时表现出类似的灵敏度。 寨卡病毒感染患者的样本中，血液的平均病毒载量为 5 × 104 RNA 拷贝/毫升，尿液的平均病毒载量为 2 × 104 拷贝/毫升。. 我们为适合当前疫情的寨卡病毒检测提供试剂和更新方案。 由于有限的灵敏度以及与一些菌株潜在的不兼容性，因此一些公布的试验可能不适合寨卡病毒检测。 临床样本中的病毒含量接近于技术检测极限，这表明使用不敏感试验将会引起假阴性结果。. Изучить диагностические возможности выявления вируса Зика с помощью полимеразной цепной реакции (ПЦР) с обратной транскриптазой (ОТ) в режиме реального времени. Авторы сравнили семь методов ОТ-ПЦР, сведения о которых были опубликованы в литературе, и два новых метода, разработанные авторами. Для выявления аналитической чувствительности каждого метода были сконструированы синтетические универсальные контрольные рибонуклеиновые кислоты (ункРНК), содержащие все целевые участки на одной из цепей РНК. Эти РНК были добавлены к образцам крови или мочи пациентов, содержащих вирус Зика африканского или азиатского происхождения в известных количествах. Одним из новых методов определялась вирусная нагрузка для 33 образцов пациентов, зараженных вирусом Зика. Олигонуклеотиды для опубликованных методов ОТ-ПЦР показали до 10 потенциальных несовпадений при определении вируса азиатского происхождения, вызвавшего нынешнюю вспышку заболеваемости, тогда как новые методы показали от 0 до 4 несовпадений. Для семи наиболее чувствительных анализов 95%-й нижний порог определения составлял от 2,1 до 12,1 копии ункРНК на реакцию. Два метода продемонстрировали меньшую чувствительность (от 17,0 до 1373,3 копии ункРНК на анализ) и сходную чувствительность при использовании образцов с добавлением ункРНК. Средняя величина вирусной нагрузки в образцах пациентов, инфицированных вирусом Зика, составила 5 × 104 копий РНК/мл для крови и 2 × 104 копийРНК/мл для мочи. Авторы предлагают реактивы и обновленные протоколы для выявления вируса Зика, вызвавшего нынешнюю вспышку заболевания. Некоторые из методов, по которым имеются опубликованные литературные данные, могут быть неподходящими для текущей ситуации из-за ограниченной чувствительности и потенциальной несовместимости с некоторыми штаммами вируса. Концентрация вируса в клинических образах была близка к техническому пределу определения, что позволяет предположить, что использование нечувствительных методов может приводить к получению ложноотрицательных результато

Acute flaccid myelitis and Guillain-Barré syndrome in children: A comparative study with evaluation of diagnostic criteria.

Background and purpose Differentiation between acute flaccid myelitis (AFM) and Guillain–Barré syndrome (GBS) can be difficult, particularly in children. Our objective was to improve the diagnostic accuracy by giving recommendations based on a comparison of clinical features and diagnostic criteria in children with AFM or GBS. Methods A cohort of 26 children with AFM associated with enterovirus D68 was compared to a cohort of 156 children with GBS. The specificity of the Brighton criteria, used for GBS diagnosis, was evaluated in the AFM cohort and the specificity of the Centers for Disease Control and Prevention (CDC) AFM diagnostic criteria in the GBS cohort. Results Children with AFM compared to those with GBS had a shorter interval between onset of weakness and nadir (3 vs. 8 days, p < 0.001), more often had asymmetric limb weakness (58% vs. 0%, p < 0.001), and less frequently had sensory deficits (0% vs. 40%, p < 0.001). In AFM, cerebrospinal fluid leukocyte counts were higher, whereas protein concentrations were lower. Spinal cord lesions on magnetic resonance imaging were only found in AFM patients. No GBS case fulfilled CDC criteria for definite AFM. Of the AFM cases, 8% fulfilled the Brighton criteria for GBS, when omitting the criterion of excluding an alternate diagnosis. Conclusions Despite the overlap in clinical presentation, we found distinctive early clinical and diagnostic characteristics for differentiating AFM from GBS in children. Diagnostic criteria for AFM and GBS usually perform well, but some AFM cases may fulfill clinical diagnostic criteria for GBS. This underlines the need to perform diagnostic tests early to exclude AFM in children suspected of atypical GBS