When we Grade Students’ Proofs, Do They Understand our Feedback?

Instructors often write feedback on students’ proofs even if there is no expectation for the students to revise and resubmit the work. It is not known, however, what students do with that feedback or if they understand the professor’s intentions. To this end, we asked eight advanced mathematics undergraduates to respond to professor comments on four written proofs by interpreting and implementing the comments. We analyzed the student’s responses using the categories of corrective feedback for language acquisition, viewing the language of mathematical proof as a register of academic English

Influence of the orientation of methylammonium lead iodide perovskite crystals on solar cell performance

Perovskite solar cells are emerging as serious candidates for thin film photovoltaics with power conversion efficiencies already exceeding 16%. Devices based on a planar heterojunction architecture, where the MAPbI(3) perovskite film is simply sandwiched between two charge selective extraction contacts, can be processed at low temperatures (<150 degrees C), making them particularly attractive for tandem and flexible applications. However, in this configuration, the perovskite crystals formed are more or less randomly oriented on the surface. Our results show that by increasing the conversion step temperature from room temperature to 60 degrees C, the perovskite crystal orientation on the substrate can be controlled. We find that films with a preferential orientation of the long axis of the tetragonal unit cell parallel to the substrate achieve the highest short circuit currents and correspondingly the highest photovoltaic performance

Whole-Body Hyperthermia (WBH) in Psychiatry

New effective therapies for managing and treating psychiatric disorders such as major depression are urgently needed. Mood-enhancing effects have repeatedly been observed after whole-body hyperthermia (WBH) treatment in other medical disciplines, and there is promising evidence that WBH may be used in psychiatry for patients suffering from depressive disorders. Most importantly, a recent study demonstrated a significant, rapid, and partially lasting reduction of depressive symptoms in patients with major depressive disorder following a single session of water-filtered infrared-A induced whole-body hyperthermia (wIRA-WBH). Underlying mechanisms of actions may include immune modulation and serotonergic neurotransmission via warm-sensitive afferent thermosensory pathways to the midbrain. Current studies are focused on verifying these earlier findings and clarifying the mechanisms involved. Herein, we report on the establishment of WBH methodology in the psychiatry setting and provide our opinions on necessary future research

A closer look into two-step perovskite conversion with X-ray scattering

Recently, hybrid perovskites have gathered much interest as alternative materials for the fabrication of highly efficient and cost-competitive solar cells; however, many questions regarding perovskite crystal formation and deposition methods remain. Here we have applied a two-step protocol where a crystalline PbI2 precursor film is converted to MAPbI3–xClx perovskite upon immersion in a mixed solution of methylammonium iodide and methylammonium chloride. We have investigated both films with grazing incidence small-angle X-ray scattering to probe the inner film morphology. Our results demonstrate a strong link between lateral crystal sizes in the films before and after conversion, which we attribute to laterally confined crystal growth. Additionally, we observe an accumulation of smaller grains within the bulk in contrast with the surface. Thus, our results help to elucidate the crystallization process of perovskite films deposited via a two-step technique that is crucial for controlled film formation, improved reproducibility, and high photovoltaic performance

Neoadjuvant bevacizumab and anthracycline-taxane-based chemotherapy in 678 triple-negative primary breast cancers; results from the geparquinto study (GBG 44)†

Background We evaluated the pathological complete response (pCR) rate after neoadjuvant epirubicin, (E) cyclophosphamide (C) and docetaxel containing chemotherapy with and without the addition of bevacizumab in patients with triple-negative breast cancer (TNBC). Patients and methods Patients with untreated cT1c-4d TNBC represented a stratified subset of the 1948 participants of the HER2-negative part of the GeparQuinto trial. Patients were randomized to receive four cycles EC (90/600 mg/m2; q3w) followed by four cycles docetaxel (100 mg/m2; q3w) each with or without bevacizumab (15 mg/kg; q3w) added to chemotherapy. Results TNBC patients were randomized to chemotherapy without (n = 340) or with bevacizumab (n = 323). pCR (ypT0 ypN0, primary end point) rates were 27.9% without and 39.3% with bevacizumab (P = 0.003). According to other pCR definitions, the addition of bevacizumab increased the pCR rate from 30.9% to 41.8% (ypT0 ypN0/+; P = 0.004), 36.2% to 46.4% (ypT0/is ypN0/+; P = 0.009) and 32.9% to 43.3% (ypT0/is ypN0; P = 0.007). Bevacizumab treatment [OR 1.73, 95% confidence interval (CI) 1.23-2.42; P = 0.002], lower tumor stage (OR 2.38, 95% CI 1.24-4.54; P = 0.009) and grade 3 tumors (OR 1.68, 95% CI 1.14-2.48; P = 0.009) were confirmed as independent predictors of higher pCR in multivariate logistic regression analysis. Conclusions The addition of bevacizumab to chemotherapy in TNBC significantly increases pCR rate

Der Umzug der Menschheit: Die transformative Kraft der Städte

Die Wucht der derzeitigen Urbanisierungsdynamik und ihre Auswirkungen sind so groß, dass sich weltweit Städte, Stadtgesellschaften, Regierungen und Internationale Organisationen diesem Trend stellen müssen. Ein „Weiter so wie bisher“, würde ohne gestaltende Urbanisierungspolitik zu einer nicht-nachhaltigen Welt-Städte-Gesellschaft führen. Nur wenn Städte und Stadtgesellschaften ausreichend handlungsfähig werden, können sie ihre Kraft für eine nachhaltige Entwicklung entfalten: In den Städten wird sich entscheiden, ob die Große Transformation zur Nachhaltigkeit gelingt. In diesem Buch werden die Erfolgsbedingungen dafür diskutiert

Humanity on the move: Unlocking the transformative power of cities

The momentum of urbanization and its impacts are so massive that we must face up to this trend. In view of the existing cognitive, technical, economic and institutional path dependencies, a policy of business as usual – i.e. an unstructured, quasi-automatic urbanization – would lead to a non-sustainable ‘world cities society’. Only if cities and urban societies are sufficiently empowered can they make use of the opportunities for sustainability and successfully follow the urban transformation pathways. The success or failure of the Great Transformation will be decided in the cities. The WBGU discusses the relevant conditions for the success of this transformation in this report

The Citation Field of Evolutionary Economics

Evolutionary economics has developed into an academic field of its own, institutionalized around, amongst others, the Journal of Evolutionary Economics (JEE). This paper analyzes the way and extent to which evolutionary economics has become an interdisciplinary journal, as its aim was: a journal that is indispensable in the exchange of expert knowledge on topics and using approaches that relate naturally with it. Analyzing citation data for the relevant academic field for the Journal of Evolutionary Economics, we use insights from scientometrics and social network analysis to find that, indeed, the JEE is a central player in this interdisciplinary field aiming mostly at understanding technological and regional dynamics. It does not, however, link firmly with the natural sciences (including biology) nor to management sciences, entrepreneurship, and organization studies. Another journal that could be perceived to have evolutionary acumen, the Journal of Economic Issues, does relate to heterodox economics journals and is relatively more involved in discussing issues of firm and industry organization. The JEE seems most keen to develop theoretical insights

Preparation of Single-Phase Films of CH3NH3Pb(I1-xBrx)3 with Sharp Optical Band Edges.

Organometallic lead-halide perovskite-based solar cells now approach 18% efficiency. Introducing a mixture of bromide and iodide in the halide composition allows tuning of the optical bandgap. We prepare mixed bromide-iodide lead perovskite films CH3NH3Pb(I1-xBrx)3 (0 ≤ x ≤ 1) by spin-coating from solution and obtain films with monotonically varying bandgaps across the full composition range. Photothermal deflection spectroscopy, photoluminescence, and X-ray diffraction show that following suitable fabrication protocols these mixed lead-halide perovskite films form a single phase. The optical absorption edge of the pure triiodide and tribromide perovskites is sharp with Urbach energies of 15 and 23 meV, respectively, and reaches a maximum of 90 meV for CH3NH3PbI1.2Br1.8. We demonstrate a bromide-iodide lead perovskite film (CH3NH3PbI1.2Br1.8) with an optical bandgap of 1.94 eV, which is optimal for tandem cells of these materials with crystalline silicon devices.We acknowledge funding from the Engineering and Physical Sciences Research Council (EPSRC) and the Winton Programme (Cambridge) for the Physics of Sustainability. THT acknowledges funding from Cambridge Australia Scholarships and the Cambridge Commonwealth Trust. D.C. acknowledges support from St. John's College Cambridge and the Winton Programme (Cambridge) for the Physics of Sustainability.This is the final published version. It's also available at: http://pubs.acs.org/doi/abs/10.1021/jz501332v

Preoperative short-term radiation therapy (25 Gy, 2.5 Gy twice daily) for primary resectable rectal cancer (phase II)

To evaluate the feasibility, effectiveness, and long-term bowel function of preoperative hyperfractionated accelerated radiotherapy in primary resectable rectal cancer. A total of 184 consecutive patients (median age 65 years, male : female=2 : 1) with clinical T3Nx rectal adenocarcinoma received preoperative pelvic radiation therapy with single fractions of 2.5 Gy twice daily (interval 6 h between fractions) to a total dose of 25 Gy within 1 week. Surgery was conducted the following week. Postoperative histology revealed UICC stage I in 33%, stage II in 26%, stage III in 34%, and stage IV in 7% of the patients. Median follow-up was 43 months (53 months for surviving patients). The actuarial 4-year-local-recurrence rate was 2.1%, overall recurrence 23%. Disease-specific and disease-free survivals at 4 years (excluding stage IV) were 82 and 69%, respectively. Overall survival for 4 years was 68%. Postoperative mortality was 0.5% (one patient), early anastomotic leakage occurred in 11.4%, and anastomotic stenosis requiring treatment in 6%, of 132 patients with primary anastomosis. Seven of 184 patients (3.8%) died of abdominal complications, all within the first year. Bowel function was satisfactory after more than 5 years. Local control in primarily resectable rectal cancer after 10 × 2.5 Gy is excellent, warranting further evaluation of this treatment