552 research outputs found
On the instructional triangle and sources of justification for actions in mathematics teaching
We elaborate on the notion of the instructional triangle, to address the question of how the nature of instructional activity can help justify actions in mathematics teaching. We propose a practical rationality of mathematics teaching composed of norms for the relationships between elements of the instructional system and obligations that a person in the position of the mathematics teacher needs to satisfy. We propose such constructs as articulations of a rationality that can help explain the instructional actions a teacher takes in promoting and recognizing learning, supporting work, and making decisions.The ideas reported in this paper have been developed in part with the support of National Science Foundation grants ESI-0353285 and DRL-0918425 to the authors.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/91281/1/On_the_instructional_triangle_PH&DC_May2012.pdf-
Agreeing is Not the Same as Accepting: Exploring Pre-Service Teachers’ Growth Mindsets
The popularity of mindset theory has resulted in a surge of mindset interventions in schools. However, with increased popularity, there is the potential for misunderstandings and hesitations about what a growth mindset fully entails. Therefore, we sought to disentangle which components of growth mindset messages pre-service teachers find hard to accept alongside their level of agreement with growth mindset questionnaire items. We used a descriptive design with both quantitative and qualitative data to explore 182 pre-service teachers’ responses to growth mindset messages. The results of this study suggest that pre-service teachers hold a growth mindset. However, despite strong quantitative endorsements, in the qualitative analyses we determined three ways in which participants found a growth mindset hard to accept: (1) the notion of mindset theory itself, (2) the level of growth, (3) and the necessary actions behind having a growth mindset. The findings of this study suggest we need to pay close attention to false growth mindsets in theory and practice
The utility of oesophageal pH monitoring in diagnosing gastroesophageal reflux disease-related chronic cough
Wstęp: Przewlekły kaszel jest częstą dolegliwością, która może pogarszać jakość życia chorych oraz wywoływać liczne powikłania. J edną z częstych jego przyczyn jest choroba refluksowa przełyku (GERD). Do metod diagnostycznych stosowanych w celu potwierdzenia diagnozy kaszlu związanego z GERD należy pH-metria przełyku. Celem badania była ocena przydatności pH-metrii przełyku oraz określenie, który z parametrów mierzonych w czasie jej wykonywania jest najczulszy w diagnostyce kaszlu związanego z GERD.Materiał i metody: U 204 chorych z przewlekłym kaszlem wykonano 24-godzinną pH-metrię przełyku. Kobiety stanowiły 65% pacjentów, a mediana wieku wyniosła 59 lat. Epizod kwaśnego refluksu rozpoznawano, gdy nagły spadek pH poniżej 4 trwał co najmniej 12 sekund. Rozpoznanie GERD opierało się na całkowitym czasie pH poniżej 4, czasie pH poniżej 4 w pozycji stojącej lub leżącej oraz wskaźniku DeMeester. Kaszel związany z GERD diagnozowano, jeżeli epizody kaszlu odnotowane przez pacjentów pojawiały się nie później niż 2 minuty po epizodzie refluksu. Z wiązek pomiędzy epizodem refluksu i wystąpieniem kaszlu oceniono za pomocą następujących parametrów: symptom index (SI ≥ 50%) lub symptom association probability (SAP ≥ 95%).Wyniki: Na podstawie wyników pH-metrii przełyku u 135 chorych (135/204, 66%) wysunięto podejrzenie GERD. U większości z nich (117/135, 87%) diagnozę postawiono na podstawie wskaźnika DeMeester. Wśród pacjentów z GERD 61 osób (61/135, 45%) spełniło kryteria kaszlu związanego z GERD, co stanowiło 30% wszystkich pacjentów. U 36 pacjentów (36/61, 59%) kaszel związany z GERD zdiagnozowano na podstawie parametru SAP, u 12 chorych (20%) na podstawie parametru SI, natomiast u 13 (21%) na podstawie obu parametrów. Współczynnik korelacji Spearmana dla SAP ≥ 95% i SI ≥ 50% wyniósł 0,46 (p < 0,05).Wnioski: Na podstawie wyników pH-metrii GERD został zdiagnozowany 2-krotnie częściej niż kaszel związany z GERD. Parametr SAP jest bardziej czuły niż SI w diagnozowaniu kaszlu związanego z GERD. Introduction: Chronic cough is a common medical complaint, which may deteriorate patients’ quality of life and cause many complications. Gastroesophageal reflux disease (GERD) is one of the frequent reasons for chronic cough. Oesophageal pH monitoring is one of the diagnostic methods performed to confirm diagnosis of GERD-related cough. The aim of the study was to analyse the utility of oesophageal pH monitoring in diagnosing GERD-related cough and to identify the most sensitive pH monitoring parameters for diagnosing GERD-related cough.Material and methods: 24-hour oesophageal pH monitoring was performed in 204 patients suffering from chronic cough. The group consisted of 65% females and the median age was 59 years. An acid reflux episode was defined as a rapid drop in pH to a value below 4 for at least 12 seconds. The diagnosis of GERD was based on total fraction time of pH < 4, upright or supine fraction time of pH < 4, or DeMeester score. The diagnosis of GERD-related cough was made if cough episodes, marked by the patients, appeared within 2 minutes after the reflux. The association between reflux episode and appearance of cough was analysed using two parameters: symptom index (SI ≥ 50%) and/or symptom association probability (SAP ≥ 95%).Results: Based on results of pH monitoring, 135 patients (135/204, 66%) were diagnosed with GERD. Among them, 117 patients (117/135, 87%) were diagnosed based on DeMeester score. Among patients with GERD, 61 patients met the criteria of GERD-related cough (61/135, 45%), i.e. 30% of the group as a whole. Thirty-six patients (36/61, 59%) were diagnosed based on SAP, 12 patients (20%) based on SI, and 13 (21%) based on both parameters. Spearman rank correlation coefficient for SAP ≥ 95% and SI ≥ 50% was 0.46 (p < 0.05).Conclusions: Based on pH monitoring results, GERD was diagnosed twice as often as GERD-related cough. SAP index is more sensitive than SI for the diagnosis of GERD-related cough
Hemorrhagic parapneumonic effusion in a 64 year-old patient as the first symptom of hemophilia B
Hemophilia B is an inherited, X chromosome-linked disease. It is usually diagnosed in childhood, sometimes in adolescence.
The commonest symptoms include spontaneous or post-traumatic bleeding into the joints and/or muscles, as well as
mucosal bleeding. Respiratory symptoms are rarely reported.
We present the case of a 64 year-old man in whom bloody parapneumonic effusion (hemothorax) was the first symptom of
hemophilia B. The reason for prolonged activated partial thromboplastin time (APTT) found on admission has not been
elucidated. Since antibiotic therapy and pleural tube thoracostomy with intrapleural streptokinase were found to be ineffective,
video-assisted thoracic surgery was performed with the right lung decortication. Post-operative treatment was complicated
by massive pleural bleeding requiring two subsequent thoracotomies. Additional blood tests revealed factor IX
deficiency and resulted in hemophilia B being diagnosed.
The presented case proves that hereditary bleeding disorders may be diagnosed even in late adulthood. Intrapleural bleeding
related to pneumonia and pleural inflammation might be the first presenting symptom. Hemophilia should be considered as
a potential cause of APTT prolongation, even in an elderly patient with atypical presentation. Explaining the reason for APTT
prolongation before the surgical procedure could have allowed to avoid severe bleeding in the described patient.Hemofilia B jest chorobą uwarunkowaną genetycznie, związaną z chromosomem X. Rozpoznawana jest najczęściej
w dzieciństwie lub młodości, a do jej typowych objawów należą samoistne lub związane z urazem krwawienia do mięśni
i stawów, a także krwawienia z błon śluzowych. Objawy ze strony układu oddechowego są rzadko opisywane.
W niniejszej pracy przedstawiono przypadek 64-letniego mężczyzny, u którego krwisty wysięk parapneumoniczny (spełniający
kryteria hemothorax) był objawem prowadzącym do rozpoznania hemofilii. Stwierdzone przy przyjęciu do szpitala wydłużenie
APTT nie zostało wyjaśnione w pierwszej fazie hospitalizacji. Próby leczenia powikłanego wysięku parapneumonicznego
antybiotykami, drenażem i fibrynolizą wewnątrzopłucnową okazały się nieskuteczne. Nawracające po zabiegu wideotorakoskopowej
dekortykacji prawego płuca krwawienie do opłucnej skłoniło do podjęcia rozszerzonych badań układu krzepnięcia.
Na podstawie ich wyników stwierdzono obniżoną aktywność czynnika IX i rozpoznano łagodną postać hemofilii B.
Przedstawiony przypadek dowodzi, że wrodzony niedobór czynnika IX może być rozpoznany nawet w późnym wieku,
a pierwsze objawy skazy krwotocznej mogą dotyczyć układu oddechowego. Dlatego też hemofilię należy uwzględnić
w diagnostyce przyczyn wydłużonego APTT także u osób w starszym wieku. Wyjaśnienie przyczyny wydłużenia APTT
przed planowanym zabiegiem operacyjnym pozwoliłoby uniknąć ciężkich powikłań pooperacyjnych u opisanego przez
nas chorego
Mediastinal lymphangioma
47-year-old women was admitted to the clinic for diagnosis of an incidentally X-ray detected enlargement
of the medistinum shadow. In the past, the patient had been operated for lymphangioma of the right forearm. Chest computer tomography (CT) showed an abnormal mass in the front mediastinum with spherical structures, which density could indicate high-protein contents. In the right mammarian gland an oval cyst (23-15 mm), similar
in character to the lesion in the mediastinum was found. The lymphangiomatic character of the lesion with the extension up to the superior aperture of the thorax was confirmed with magnetic resonans imaging (MRI).Duetothe extensive changes and lack of symptoms, the patient was disqualified for surgical treatment and remains under further observation
Impact of COVID-19 on cancer service delivery: results from an international survey of oncology clinicians.
To report clinician-perceived changes to cancer service delivery in response to COVID-19.
Multidisciplinary Australasian cancer clinician survey in collaboration with the European Society of Medical Oncology.
Between May and June 2020 clinicians from 70 countries were surveyed; majority from Europe (n=196; 39%) with 1846 COVID-19 cases per million people, Australia (AUS)/New Zealand (NZ) (n=188; 38%) with 267/236 per million and Asia (n=75; 15%) with 121 per million at time of survey distribution.
Medical oncologists (n=372; 74%), radiation oncologists (n=91; 18%) and surgical oncologists (n=38; 8%).
Eighty-nine per cent of clinicians reported altering clinical practices; more commonly among those with versus without patients diagnosed with COVID-19 (n=142; 93% vs n=225; 86%, p=0.03) but regardless of community transmission levels (p=0.26). More European clinicians (n=111; 66.1%) had treated patients diagnosed with COVID-19 compared with Asia (n=20; 27.8%) and AUS/NZ (n=8; 4.8%), p<0.001. Many clinicians (n=307; 71.4%) reported concerns that reduced access to standard treatments during the pandemic would negatively impact patient survival. The reported proportion of consultations using telehealth increased by 7.7-fold, with 25.1% (n=108) of clinicians concerned that patient survival would be worse due to this increase. Clinicians reviewed a median of 10 fewer outpatients/week (including non-face to face) compared with prior to the pandemic, translating to 5010 fewer specialist oncology visits per week among the surveyed group. Mental health was negatively impacted for 52.6% (n=190) of clinicians.
Clinicians reported widespread changes to oncology services, in regions of both high and low COVID-19 case numbers. Clinician concerns of potential negative impacts on patient outcomes warrant objective assessment, with system and policy implications for healthcare delivery at large
Kinstate intervention in ethnic conflicts : Albania and Turkey compared
Albania and Turkey did not act in overtly irredentist ways towards their ethnic brethren in neighboring states after the end of communism. Why, nonetheless, did Albania facilitate the increase of ethnic conflict in Kosovo and Macedonia, while Turkey did not, with respect to the Turks of Bulgaria? I argue that kin-states undergoing transition are more prone to intervene in external conflicts than states that are not, regardless of the salience of minority demands in the host-state. The transition weakens the institutions of the kin-state. Experiencing limited institutional constraints, self-seeking state officials create alliances with secessionist and autonomist movements across borders alongside their own ideological, clan-based and particularistic interests. Such alliances are often utilized to advance radical domestic agendas. Unlike in Albania's transition environment, in Turkey there were no emerging elites that could potentially form alliances and use external movements to legitimize their own domestic existence or claims
Gás "de xisto" no Brasil: uma necessidade?
Nos últimos anos cresceu o número de defensores do uso do gás "de xisto" como a melhor alternativa para baratear a produção de energia no Brasil. Este texto apresenta a formação de gás natural não convencional em rochas sedimentares no Brasil, bem como o fraturamento hidráulico e seus impactos socioambientais. Por fim, pondera sobre a necessidade de utilizar essas reservas no Brasil, já que a questão central é discutir o uso da energia no país
Attachment Predicts College Students’ Knowledge, Attitudes, and Skills for Working with Infants, Toddlers, and Families
Research Findings:Adults’ attitudes about attachment relationships are central to how they perceive and respond to children. However, little is known about how attachment styles are related to teachers’ attitudes toward and interactions with infants and toddlers. From a survey of 207 students taking early childhood (EC) courses at 4 U.S. universities, we report relations among students’ attachment styles and their (a) career goals, (b) attitudes about caring for and educating infants and young children, and (c) interaction skills for responding in developmentally supportive ways. Overall, attachment security was positively associated with career goals focused on working with younger children, knowledge about infant/toddler development, attitudes that acknowledge the importance of adult support in children’s development, and developmentally supportive interaction skills. Students who scored high on attachment fearfulness minimized the importance of adults in children’s lives, minimized the importance of the early
years for later learning, and endorsed strict and controlling forms of child guidance.
Practice or Policy: A conceptual mediation model linking a path from attachment to caregiving skill through knowledge and attitudes is articulated. We propose a person-centered pedagogy for infant/toddler professional preparation that provides opportunities for reflection on one’s own attachment and its effects on work with young childre
Gravitational wave astronomy of single sources with a pulsar timing array
Abbreviated:
We investigate the potential of detecting the gravitational wave from
individual binary black hole systems using pulsar timing arrays (PTAs) and
calculate the accuracy for determining the GW properties. This is done in a
consistent analysis, which at the same time accounts for the measurement of the
pulsar distances via the timing parallax.
We find that, at low redshift, a PTA is able to detect the nano-Hertz GW from
super massive black hole binary systems with masses of \sim10^8 -
10^{10}\,M_{\sun} less than \,years before the final merger, and
those with less than years before merger may allow us to
detect the evolution of binaries.
We derive an analytical expression to describe the accuracy of a pulsar
distance measurement via timing parallax. We consider five years of bi-weekly
observations at a precision of 15\,ns for close-by (\,kpc)
pulsars. Timing twenty pulsars would allow us to detect a GW source with an
amplitude larger than . We calculate the corresponding GW and
binary orbital parameters and their measurement precision. The accuracy of
measuring the binary orbital inclination angle, the sky position, and the GW
frequency are calculated as functions of the GW amplitude. We note that the
"pulsar term", which is commonly regarded as noise, is essential for obtaining
an accurate measurement for the GW source location.
We also show that utilizing the information encoded in the GW signal passing
the Earth also increases the accuracy of pulsar distance measurements. If the
gravitational wave is strong enough, one can achieve sub-parsec distance
measurements for nearby pulsars with distance less than \,kpc.Comment: 16 pages, 5 figure,, accepted by MNRA
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