Will we ever teach mathematics again in the way we used to before the pandemic?

After about two years of emergency remote teaching during the pandemic, the teaching of mathematics is slowly returning to (what used to be called) normal. However, after the period of mostly teaching online, there is uncertainty about the extent to which we will return to the way we were teaching before. In this survey paper we attempt to give some background to the impact that emergency remote teaching may have had on teaching mathematics. We examine the possible social implications and then focus on the changing mathematics classroom, focusing on the actual mathematics curriculum, learning design and assessment, the role of collaborative activities and social media, educational videos, and the role of family and parents in future. There are indicators from the literature that educators may not return to the traditional way of teaching entirely, especially in secondary and higher education. We conclude with describing some possible new research areas that have developed through emergency remote teaching, including online education for younger learners, local learning ecosystems, the role of family and parents, instructional design, and the mathematics content of curricula.

The impact of COVID-19 on the format and nature of academic conferences in mathematics education.

The global COVID-19 pandemic has provided an opportunity to re-examine the possibility of organising virtual conferences in mathematics education, in which the social needs of participants can also be addressed. In this study we investigated the future impact that this change may have on the format and nature of mathematics education conferences. The study was conducted in two phases. We used an online questionnaire in which we asked participants to give us some input on the issues above. In the second phase of the project, focus group interviews were conducted with international mathematics education researchers. This study is an exploratory study, in which the sample was not developed in a way that could generate comparisons. The aim of the study was to raise possibilities about what may be the future of mathematics education conferences. Findings indicate that although academics are pro-actively thinking about alternative conference formats, the proven value of face-to-face conferences is still very real, showing that it is too early for us to have a clear vision of the future format of academic conferences.

Roles of technologies for future teaching in a pandemic: activity, agency, and humans-with-media.

Research literature on the role of mathematics teachers during the COVID-19 crisis shows that teacher preparation for emergency situations is required. In reporting on this exploratory study, we present and analyse lesson plans created by seven future teachers for mathematics classes during the pandemic. Data were collected between April and October 2021 from 16 four-hour class sessions in a Mathematics Degree Program at a public university in Medellín, Colombia. The notion of Humans-with-Media and the Learning by Expanding theory were used as frameworks to understand what roles prospective mathematics teacher (PMTs) assign to technologies for teaching in pandemic conditions. The PMTs' uses of technology for teaching mathematics during a pandemic were categorized. The results show that technology was used to reorganize and reproduce mathematics teaching practices. This report addresses the impact of technology on the activity system, and we conclude with a discussion of opportunities and limitations of students' conceptions about teaching and technology during a pandemic.

The future of mathematics education since COVID-19: humans-with-media or humans-with-non-living-things.

The COVID-19 pandemic has changed the agenda of mathematics education. This change will be analyzed by looking at three trends in mathematics education: the use of digital technology, philosophy of mathematics education, and critical mathematics education. Digital technology became a trend in mathematics education in response to the arrival of a different kind of artifact to the mathematics classroom. It was thrust into the spotlight as the pandemic suddenly moved classrooms online around the world. Challenges specific to mathematics education in this context must be addressed. The link between the COVID-19 pandemic and digital technology in education also raises epistemological issues highlighted by philosophy of mathematics education and critical mathematics education. Using the notion that the basic unit of knowledge production throughout history is humans-with-media, I discuss how humans are connected to the virus, how it has laid bare social inequality, and how it will change the agendas of these three trends in mathematics education. I highlight the urgent need to study how mathematics education happens online for children when the home environment and inequalities in access to digital technologies assume such significant roles as classes move on-line. We need to understand the political role of agency of artifacts such as home in collectives of humans-with-media-things, and finally we need to learn how to implement curricula that address social inequalities. This discussion is intertwined with examples.

Abdominal Surgery in Crohn's Disease: Risk Factors for Complications.

INTRODUCTION: Abdominal surgery in patients with Crohn's disease (CD) is challenging, especially in the biologic era. The aim of this study was to evaluate factors associated with increased risk for postoperative complications in CD. METHODS: A retrospective study was conducted with consecutive patients who underwent abdominal surgery for CD from January 2012 to January 2018. RESULTS: Of 103 patients, 32% had postoperative complications. Gender, age, disease location and phenotype, hemoglobin and albumin levels, previous abdominal surgery, and preoperative optimization did not differ between the groups with or without complications. Thirty-five percent of the patients were under anti-TNF therapy, and this medication was not associated with increased risk for postoperative complications. Time since the onset of the disease was significantly higher in patients with complications (12.9 vs. 9.4, p = 0.04). In multivariate analysis, creation of ostomy and urgent surgery were the only variables independently associated with increased risk for complications (OR 3.2, 95% CI 1.12-9.46 and OR 2.94, 95% CI 0.98-9.09, respectively). CONCLUSION: Urgent surgery for CD should preferably be performed in specialized centers, and creation of stoma is not necessarily associated with lower rate of postoperative complications but rather less severe complications.

Transformation of the mathematics classroom with the internet.

Growing use of the internet in educational contexts has been prominent in recent years. In this survey paper, we describe how the internet is transforming the mathematics classroom and mathematics teacher education. We use as references several reviews of use of the internet in mathematics education settings made in recent years to determine how the field has evolved. We identify three domains in which new approaches are being generated by mathematic educators: principles of design of new settings; social interaction and construction knowledge; and tools and resources. The papers in this issue reflect different perspectives developed in the last decade in these three domains, providing evidence of the advances in theoretical frameworks and support in the generation of new meanings for old constructs such as 'tool', 'resources' or 'learning setting'. We firstly highlight the different ways in which the use of digital technologies generates new ways of thinking about mathematics and the settings in which it is learnt, and how mathematics teacher educators frame the new initiatives of initial training and professional development. In this survey paper, we identify trends for future research regarding theoretical and methodological aspects, and recognise new opportunities requiring further engagement.

Risk factors for implant failure: a retrospective study in an educational institution using GEE analyses.

This study aimed to evaluate dental implant outcomes and to identify risk factors associated with implant failure over 12 years via dental records of patients attending an educational institution. Dental records of 202 patients receiving 774 dental implants from 2002 to 2014 were analyzed by adopting a more reliable statistical method to evaluate risk factors with patients as the unit [generalized estimating equation (GEE)]. Information regarding patient age at implantation, sex, use of tobacco, and history of systemic diseases was collected. Information about implant location in the arch region and implant length, diameter, and placement in a grafted area was evaluated after 2 years under load. Systemic and local risk factors for early and late implant failure were studied. A total of 18 patients experienced 25 implant failures, resulting in an overall survival rate of 96.8% (2.84% and 0.38% early and late implant failures, respectively). The patient-based survival rate was 91.8%. GEE univariate and multivariate analyses revealed that a significant risk factor for implant failure was the maxillary implant (p = 0.006 and p = 0.014, respectively). Bone grafting appeared to be a risk factor for implant failure (p = 0.054). According to GEE analyses, maxillary implants had significantly worse outcomes in this population and were considered to be a risk factor for implant failure. Our results suggested that implants placed in a bone augmentation area had a tendency to fail.

Risk factors for implant failure: a retrospective study in an educational institution using GEE analyses

Abstract This study aimed to evaluate dental implant outcomes and to identify risk factors associated with implant failure over 12 years via dental records of patients attending an educational institution. Dental records of 202 patients receiving 774 dental implants from 2002 to 2014 were analyzed by adopting a more reliable statistical method to evaluate risk factors with patients as the unit [generalized estimating equation (GEE)]. Information regarding patient age at implantation, sex, use of tobacco, and history of systemic diseases was collected. Information about implant location in the arch region and implant length, diameter, and placement in a grafted area was evaluated after 2 years under load. Systemic and local risk factors for early and late implant failure were studied. A total of 18 patients experienced 25 implant failures, resulting in an overall survival rate of 96.8% (2.84% and 0.38% early and late implant failures, respectively). The patient-based survival rate was 91.8%. GEE univariate and multivariate analyses revealed that a significant risk factor for implant failure was the maxillary implant (p = 0.006 and p = 0.014, respectively). Bone grafting appeared to be a risk factor for implant failure (p = 0.054). According to GEE analyses, maxillary implants had significantly worse outcomes in this population and were considered to be a risk factor for implant failure. Our results suggested that implants placed in a bone augmentation area had a tendency to fail.

Mucinous adenocarcinona of the appendix.

Diagnosis of malignancy in the vermiform appendix is quite rare. The most common histological malignant neoplasia found in this tiny portion of the gastrointestinal tract is represented by the mucinous adenocarcinoma. This entity predominates in males around 50 years of age, and clinical presentation usually mimics or occurs along with an acute appendicitis. Early diagnosis is outside the rule since most cases at this stage are symptomless. The authors present the case of a 59-year-old female patient who looked for medical attention complaining of abdominal pain. Physical examination and laboratory workup were poor in diagnostic findings. The computed tomography images were compatible with the diagnosis of appendicitis and/or appendiceal neoplasia. The patient underwent a laparotomy and right hemicolectomy. The histological examination disclosed a moderately differentiated mucinous adenocarcinoma of the appendix stage T4a, N0, M0. The patient outcome was uneventful and was referred to an oncological center.

Reconstrução de parede abdominal com tela aloplástica após infecção por micobactéria / Abdominal wall reconstruction with alloplastic mesh after Mycobacterium infection", "_e": "n

Os autores relatam o caso de paciente do sexo feminino, com 51 anos de idade, submetida a histerectomia por videolaparoscopia, com evolução para quadro de infecção por micobactéria. Realizado tratamento com associação de antimicrobianos, debridamento cirúrgico e reconstrução de parede abdominal com tela sintética. Na evolução pós-operatória, a paciente apresentou herniação de parede abdominal, corrigida com a substituição por nova tela aloplástica e abdominoplastia. O relato do caso alerta para a importância dos cuidados na prevenção da infecção por micobactéria e do adequado tratamento para otimização funcional e estética.

The present report is a case study of a 51-year-old woman who underwent hysterectomy by videolaparoscopy, and eventually developed a mycobacterial infection. Treatment comprised antimicrobial administration, surgical debridement, and reconstruction of the abdominal wall with a synthetic mesh. During the postoperative period, the herniation of the abdominal wall required substitution of the mesh and subsequent abdominoplasty. This case report indicates the importance of preventing mycobacterium infection and provides treatment guidelines to optimize functional and aesthetic results.

Ressecções eletiva e de urgência para tratamento de neoplasia maligna do cólon em hospital universitário: estudo de 66 casos / Elective and urgency resections for the treatment of colon neoplasm in University Hospital: study of 66 cases

O câncer de cólon é uma doença de alta prevalência e mortalidade, cujo tratamento baseia-se na ressecção cirúrgica. A possibilidade de cura aumenta com o diagnóstico precoce, daí a importância dos programas de rastreamento populacional do câncer colorretal. O presente estudo analisou, retrospectivamente, 66 pacientes submetidos a ressecções do cólon por neoplasia em um período de 58 meses no Hospital Universitário da Universidade de São Paulo. Os pacientes foram divididos em dois grupos: grupo 1, submetidos a cirurgia eletiva (28 pacientes), e grupo 2, submetidos a cirurgia de urgência (38 pacientes). Os grupos foram comparados com relação às variáveis sexo, idade, apresentação clínica, aspectos da técnica cirúrgica, sítio anatômico da lesão, estádio patológico, taxas de complicações, permanência hospitalar pós-operatória e óbitos na internação. Verificou-se no presente estudo que a idade entre os grupos foi semelhante. Houve uma predominância do sexo masculino entre os pacientes operados de urgência. No grupo de cirurgia eletiva, o principal sintoma foi a hematoquezia, enquanto os operados na urgência, tinham como principal queixa dor abdominal. A grande maioria dos pacientes, no momento da cirurgia, apresentava-se sintomática há meses. Os pacientes operados na urgência apresentaram mais tumores pT4 e os operados eletivamente apresentaram mais neoplasias em estádio I. Em ambos os grupos, o caráter oncológico dos procedimentos foi preservado, bem como foi alto o índice de anastomoses primárias (81,8 por cento). As taxas de complicações pós-operatórias, o tempo de permanência hospitalar pós-operatório e a mortalidade foram semelhantes.

Colon cancer is a disease with high frequency and mortality rates, which treatment is based, fundamentally, on surgical resection. Because early diagnosis increases the curability, it is essential to have a screening programs offering early treatment. A retrospective study was performed, including 66 patients who underwent colonic resections due to cancer, for 58 months at Hospital Universitario of Universidade de São Paulo. These patients were divided in two groups, group 1, submitted to elective surgery (28 patients), and group 2, submitted to emergency surgery (38 patients). The groups were comparable for gender, age, clinical presentation, surgical procedure techniques, tumor distribution, TNM stage, morbidity, postoperative hospital stay and postoperative mortality. No difference was observed in patients’age. Males were predominant in the urgency surgery group. Lower gastrointestinal bleeding was the main symptom in the elective group, whereas abdominal pain was the main symptom in the urgency group. Mostly of the patients were having symptoms for months at the time of surgery. Urgency group patients presented more pT4 tumors, and elective group patients presented more stage I cancer. In both groups the oncologic approach was achieved, as well as primary anastomosis rates (81.8 percent). No differences in average hospital stay, hospital morbidity or postoperative mortality were recorded.

Linfoma ileal primário como uma causa de intussuscepção ileocecal recorrente / Primary ileal lymphoma as a cause of recurrent ileocecal

INTRODUÇÃO: A intussuscepção ocorre quando um segmento proximal do intestino invagina para dentro do lúmen do segmento distal adjacente. Esta patologia é relativamente comum em crianças, sendo geralmente idiopática, diferentemente do que é evidenciado em adolescentes e adultos, os quais apresentam uma causa orgânica comprovada na maioria dos casos. O linfoma intestinal como etiologia desta patologia é extremamente raro. RELATO DE CASO: Um paciente de 16 anos, masculino, referindo dor abdominal em quadrante inferior direito há 36 horas associada a vômitos e fezes com sangue vivo compareceu em nosso serviço. O exame físico se apresentava dentro da normalidade exceto por uma massa palpável no quadrante inferior direito. A ultra-sonografia abdominal revelou intussuscepção ileocecal. A colonoscopia demonstrou uma massa protuberante proveniente do orifício da válvula ileocecal que foi reduzida, tendo o paciente um alívio completo dos sintomas. Três semanas após, o paciente retornou ao nosso hospital com recorrência dos sintomas. Uma laparotomia exploradora foi realizada evidenciando uma massa polipóide no íleo terminal com intussuscepção para dentro do ceco. Uma colectomia direita ampliada foi realizada. Após exame patológico da peça e estadiamento tumoral, um linfoma de Burkitt primário foi diagnosticado. A recuperação pós-operatória não apresentou intercorrências e o paciente foi encaminhado para quimioterapia adjuvante.

INTRODUCTION: Intussusception occurs when a proximal segment of bowel telescopes into the lumen of the adjacent distal segment. It is common in children being usually idiophatic, in contrast to adolescents and adults, who have a demonstrable etiology in most cases. Intestinal lymphoma is an unusual cause of intussusception in adolescents and adults. CASE REPORT: A 16 year-old male presented with right lower quadrant abdominal pain lasting for 36 hours, with vomiting and bloody stool. Physical examination was unremarkable except for a palpable mass at the right lower quadrant. Abdominal sonography revealed ileocecal intussusception. Colonoscopy showed a protruding mass from the orifice of ileocecal valve which was reduced, and the patient had full withdrawal of symptoms. Three weeks later, the patient came back to our hospital with recurrent symptoms. Laparotomy was performed and a polypoid mass was noted at the terminal ileum with intussusception into the cecum. A right hemicolectomy was performed. After pathologic examination and tumor staging, a primary Burkitt lymphoma of the distal ileum was diagnosed. Postoperative convalescence was uneventful and the patient was referred to adjuvant chemotherapy.

Comparison of the effects of carbon dioxide and helium pneumoperitoneum on renal function.

BACKGROUND AND PURPOSE: Carbon dioxide pneumoperitoneum is associated with significant hypercarbia and acidosis. The aim of this study is to evaluate the effects of carbon dioxide and helium pneumoperitoneum on renal function. MATERIALS AND METHODS: Thirty adult dogs were put randomly into one of three groups (n=10 animals each): group A--pneumoperitoneum not performed; group B--CO(2) pneumoperitoneum; and group C--helium pneumoperitoneum. The groups were analyzed with consideration given to body weight, hematologic values, hemodynamic parameters (heart rate, mean arterial pressure, central venous pressure, cardiac output, stroke volume, systemic vascular resistance, pulmonary vascular resistance, left cardiac work index, cardiac index, mean pulmonary artery pressure, and pulmonary capillary wedge pressure), and renal function (plasma renin activity, urinary output, creatinine clearance, and sodium excretory fraction). RESULTS: An accentuated decrease in urinary output was observed during pneumoperitoneum in groups B and C compared to the control group. In groups B and C, creatinine clearance declined significantly during pneumoperitoneum in comparison to group A, but after deflation a faster recovery of glomerular filtration was noticed for group C, and a significant increase in sodium excretory fraction was seen for group B. On the other hand, in comparison to the control group, group B had a significant increase in plasma renin activity, with late recovery of glomerular function. CONCLUSION: Helium ameliorates renal alterations when used for pneumoperitoneum, and it might be used for patients with compromised renal function who have to undergo laparoscopic surgery.

Concurrent development of Crohn disease and myelodysplastic syndrome in a child: case report and literature review.

A small number of cases of Crohn disease associated with myelodysplastic syndromes or leukemia have been reported in adults in the last 25 years in the English-language medical literature. The authors report a case of a 9-year-old boy who developed Crohn disease and myelodysplastic syndrome concurrently. Analysis of his bone marrow showed a chromosome 20 abnormality. Although chromosome 20 abnormalities have been reported in a minority of these patients, the significance of this association remains unclear at the present time.

Manifestações extra-esofágicas da doença do refluxo gastroesofágico / Extraesophageal manifestations of gastroesophageal reflux disease

A doença do refluxo gastroesofágico freqüentemente se apresenta com pirose e regurgitação, os chamados sintomas típicos. Porém, um subgrupo de pacientes apresenta um conjunto de sinais e sintomas que não estão relacionados diretamente ao dano esofágico. A esse conjunto dá-se o nome de manifestações extra-esofágicas da doença do refluxo gastroesofágico. Compreendem, principalmente, broncoespasmo, tosse crônica e alterações inflamatórias na laringe (chamados manifestações atípicas). Apesar de essas manifestações formarem um grupo heterogêneo, algumas considerações gerais englobam todos os subgrupos: embora a associação entre a doença do refluxo gastroesofágico e as manifestações extra-esofágicas esteja bem estabelecida, uma relação entre causa e efeito definitiva ainda não está elucidada; em relação à patogênese das manifestações extra-esofágicas, os principais mecanismos propostos são a injúria direta do tecido extra-esofágico pelo conteúdo ácido gástrico refluído e o reflexo esôfago-brônquico mediado pelo nervo vago; a doença do refluxo gastroesofágico pode não ser incluída no diagnóstico diferencial do grupo de pacientes que apresenta somente os sintomas atípicos. Este artigo revisa as manifestações extra-esofágicas da doença do refluxo gastroesofágico encontradas na literatura, discutindo a epidemiologia, patogênese, diagnóstico e tratamento, com foco nas apresentações mais estudadas e estabelecidas.

Extraesophageal manifestations of gastroesophageal reflux disease.

Gastroesophageal reflux disease often presents as heartburn and acid reflux, the so-called "typical" symptoms. However, a subgroup of patients presents a collection of signs and symptoms that are not directly related to esophageal damage. These are known collectively as the extraesophageal manifestations of gastroesophageal reflux disease. Principal among such manifestations are bronchospasm, chronic cough and laryngitis, which are classified as atypical symptoms. These manifestations comprise a heterogeneous group. However, some generalizations can be made regarding all of the subgroups. First, although the correlation between gastroesophageal reflux disease and the extraesophageal manifestations has been well established, a cause-and-effect relationship has yet to be definitively elucidated. In addition, the main proposed pathogenic mechanisms of extraesophageal reflux are direct injury of the extraesophageal tissue (caused by contact with gastric acid) and the esophagobronchial reflex, which is mediated by the vagus nerve. Furthermore, gastroesophageal reflux disease might not be considered in the differential diagnosis of patients presenting only the atypical symptoms. In this article, we review the extraesophageal manifestations of gastroesophageal reflux disease, discussing its epidemiology, pathogenesis, diagnosis and treatment. We focus on the most extensively studied and well-established presentations.

Effects of enalaprilat on the renin-angiotensin-aldosterone system and on renal function during CO2 pneumoperitoneum.

BACKGROUND AND PURPOSE: Mechanical and hormonal factors have been implicated in pneumoperitoneum-induced renal alterations. The aim of this study was to evaluate the effects of enalaprilat (Vasotec) administration on renal function during CO2 pneumoperitoneum, given that this drug, which is an angiotensin-converting enzyme inhibitor, by inhibiting the renin-angiotensin-aldosterone system, alters hormone-induced changes during pneumoperitoneum. MATERIALS AND METHODS: Thirty adult dogs were randomly assigned to one of three groups (N = 10 each): group A (pneumoperitoneum not performed); group B (CO2 + enalaprilat); group C CO2 only. The groups were analyzed with consideration for body weight, hematologic values, hemodynamic parameters, and renal function (plasma renin activity, urinary debt, creatinine clearance, and sodium-excretory fraction). RESULTS: Hemodynamic and acid-basic parameter differences did not influence renal function. Plasma renin activity decreased significantly in group B compared with group C and stayed close to the values in group A. Creatinine clearance remained constant in group B, while in group C, creatinine clearance dropped, and this difference was statistically significant. Urinary debt and sodium-excretory fraction increased in group B during pneumoperitoneum and 60 minutes after this period in comparison with the other groups without reaching statistical significance. CONCLUSION: The decline in urinary debt and in creatinine clearance observed during pneumoperitoneum was less accentuated with administration of enalaprilat.

Efeitos do enalaprilato sobre o sistemaa renina-angiotensina-aldosterona e a função renal durante o pneumoperitônio com gás carbônico / The effects of enalapprilat administration on the renin-angiotensin-aldosterone system and on renal function during the CO2 pneumoperitoneum

Este estudo tem por objetivo demonstrar os efeitos do enalaprilato, uma droga bloqueadora do sistema renina angiotensina aldosterona na função renal durante o pneumoperitônio com gás carbônico. Trinta cães adultos foram divididos em três grupos: Grupo A-controle sem pneumoperitônio, grupo B- CO2 + enalaprilato e grupo C- CO2. Observou-se que, houve queda significativa da atividade plasmática de renina no grupo B em relação ao grupo C / The aim of this study is to demonstrate the effects of enalaprilat administration on renal function during the CO2 pneumoperitoneum. Thirty adult dogs were randomized into one of three groups (n=10 animals each): Group A-pneumoperitoneum not performed; group B- CO2 + enalaprilat and group C- CO2. With enalaprilat administration, we concluded that: Serum renin activity dropped significantly in group B) when compared to group C. Creatinine clearance remained constant in group B as in group A; therefore, enalaprilat prevented this parameter fall which occurred in group C The blockade in the renin-angiotensin-aldosterone system caused an increase of urinary debt and a better sodium excretory fraction in group B compared to group C, although it did not reach statistical difference...