Energy and material flows of megacities

Understanding the drivers of energy and material flows of cities is important for addressing global environmental challenges. Accessing, sharing, and managing energy and material resources is particularly critical for megacities, which face enormous social stresses because of their sheer size and complexity. Here we quantify the energy and material flows through the world’s 27 megacities with populations greater than 10 million people as of 2010. Collectively the resource flows through megacities are largely consistent with scaling laws established in the emerging science of cities. Correlations are established for electricity consumption, heating and industrial fuel use, ground transportation energy use, water consumption, waste generation, and steel production in terms of heating-degree-days, urban form, economic activity, and population growth. The results help identify megacities exhibiting high and low levels of consumption and those making efficient use of resources. The correlation between per capita electricity use and urbanized area per capita is shown to be a consequence of gross building floor area per capita, which is found to increase for lower-density cities. Many of the megacities are growing rapidly in population but are growing even faster in terms of gross domestic product (GDP) and energy use. In the decade from 2001–2011, electricity use and ground transportation fuel use in megacities grew at approximately half the rate of GDP growth.The remarkable growth of cities on our planet during the past century has provoked a range of scientific inquires. From 1900–2011, the world’s urban population grew from 220 million (13% of the world’s population) to 3,530 million (52% of the world’s population) (1, 2). This phenomenon of urbanization has prompted the development of a science of cities (3, 4), including interdisciplinary contributions on scaling laws (5, 6), networks (7), and the thermodynamics of cities (8, 9). The growth of cities also has been strongly linked to global challenges of environmental sustainability, making the study of urban energy and material flows, e.g., for determining greenhouse gas emissions from cities and urban resource efficiency (10–19), important.At the pinnacle of the growth of cities is the formation of megacities, i.e., metropolitan regions with populations in excess of 10 million people. In 1970, there were only eight megacities on the planet (SI Appendix, Fig. S1). By 2010, the number had grown to 27, and a further 10 megacities likely will exist by 2020 (20). In 2010, 460 million people (6.7% of the global population) lived in the 27 megacities. The sheer size and complexity of megacities gives rise to enormous social and environmental challenges. Megacities often are perceived to be areas of high global risk (i.e., threatened by economic, environmental, geopolitical, societal, and technological risks with potential impacts across entire countries) with extreme levels of poverty, vulnerability, and social–spatial fragmentation (21–24). To provide adequate water and wastewater services, many megacities require massive technical investment and appropriate institutional development (25, 26). Many inhabitants of megacities also suffer severe health impacts from air pollution (27). However, these factors present only one side; the megacities include some of the wealthiest cities in the world (albeit with large disparities between citizens). Even the poorer megacities are seen by some as potential centers of innovation, where high levels of resource efficiency might reduce global environmental burdens (21, 28, 29). Whether megacities can develop as sustainable cities depends to a large extent on how they obtain, share, and manage their energy and material resources.The aims of our study are first to quantify the energy and material flows for the world’s 27 megacities, based on 2010 population, and second to identify physical and economic characteristics that underlie these resource flows at multiple scales. This goal entailed developing a common data-collection process applied to all the megacities. The cities were identified based on Brinkhoff’s database of metropolitan regions (www.citypopulation.de/world/Agglomerations.html; SI Appendix, Fig. S2). The megacities are essentially common commuter-sheds of more than 10 million people; most are contiguous urban regions, but a contiguous area is not a requirement; for example, the London megacity includes a ring of commuter towns outside the Greater London area. Megacities can spread across political borders. They include large tracts of suburban regions, which can have higher per capita resource flows than central areas (30, 31). We quantify energy flows for the dominant direct forms of consumption in megacities. A wide and complex range of materials flow through cities; here the focus is on water, concrete, steel, and waste. We show how values of aggregate resource use of all megacities generally are consistent with the scaling laws that have been developed for cities (5, 6). We then analyze factors correlated with energy and material flow at macro- and microscales; discuss megacities with low, high, and efficient use of resources; and examine changes over time.     

Differences in Stereotypic Behavior in Adults Diagnosed with Autism Spectrum Disorders Using the DSM-IV-TR and the DSM-5

The purpose of the current study was to investigate differences in the frequency of stereotypic behavior (e.g., engaging in repetitive activities; repetitive body movements such as rocking, spinning, handflapping; repetition of words or sounds; and perseveration on specific topics) using a psychometrically sound measure, the Diagnostic Assessment for the Severely Handicapped, second edition (DASH-II). The sample investigated included 261 adults with severe or profound intellectual disability (ID), 51 of whom met criteria for ASD according to the DSM-5; 84 of whom met criteria for the DSM-IV-TR, but no longer qualify for an ASD diagnosis with the new criteria; and a control group of 126 adults who did not qualify for an ASD diagnosis according to either version of the DSM. The DSM-5 captured a more impaired population in terms of stereotypies, though a significant difference remains between those who no longer meet criteria and a control group with ID who did not meet criteria for ASD under either version of the DSM. Highlights ? Approximately 38 % of adults with ID currently meeting criteria for autism under the DSM-IV-TR did not meet the DSM-5 criteria. ? Those who continued to meet criteria for ASD had higher scores on the DASH-II stereotypy subscale. ? People meeting DSM-IV but not DSM-5 criteria had significantly more stereotypic behavior than adults without ASD.     

Measurement of gastric emptying rate in humans by real-time ultrasound

Simultaneous studies of gastric emptying by ultrasound and scintigraphy were performed in 14 subjects to assess the use of ultrasound for the measurement of gastric emptying rate. The presence of air in the stomach prevented the acquisition of gastric emptying data by ultrasound in 3 of the 14 subjects. In the remaining 11 subjects there was no significant difference between values for the half-time (t1/2) of gastric emptying obtained by scintigraphy [for anterior imaging, mean t1/2 = 20.9 +/- 9.9 min (+/- SD); for anterior and posterior imaging, geometric mean t1/2 = 21.1 +/- 10.5 min (+/- SD)] compared with those derived by ultrasound [mean t1/2 = 20.2 +/- 10.0 min (+/- SD), p greater than 0.05 for each comparison]. A significant correlation between the t1/2 of gastric emptying derived by scintigraphy (anterior scanning and geometric mean of counts obtained by anterior and posterior scanning) and the t1/2 measured by ultrasound was obtained (r2 = 0.7, 0.69, respectively). These results imply that ultrasound can be used for the valid assessment of the gastric emptying rate in humans.     

Imatinib mesylate (STI571) treatment in patients with chronic-phase chronic myelogenous leukaemia previously submitted to autologous stem cell transplantation

Imatinib mesylate (STI571) is a highly effective and well-tolerated treatment for patients with chronic-phase chronic myeloid leukaemia (CML), but information on its efficacy and tolerance in intensively pretreated patients is scarce. Thirty-three chronic-phase CML patients who were resistant or intolerant to interferon (IFN) and had been previously submitted to autologous stem cell transplantation were treated with imatinib for a median of 14 months (range: 6-19 months). Seven patients were in haematological response (HR) at the start of treatment; the remaining 26 attained a HR at a median of 3 weeks (range: 1-4 weeks). Major cytogenetic response rates at 3, 6 and 12 months were 42%, 45% and 55%, respectively, including 21%, 24% and 33% complete responses. Grade 3-4 neutropenia, thrombocytopenia and anaemia developed in 33%, 27% and 12% of patients respectively. Non-haematological toxicity included superficial oedema (21% of patients), gastrointestinal symptoms (18%), muscle cramps (15%), skin rash and liver enzyme increase (3% each). These results were not significantly different from those in 65 chronic-phase CML patients, resistant or intolerant to interferon without a previous ASCT, who were included in the same protocol. Imatinib mesylate is effective and safe in chronic-phase CML patients with a previous history of intensive treatment.     

The value of detecting surface and cytoplasmic antigens in acute myeloid leukaemia

The immunophenotype of leukaemia cells from 60 patients with acute myeloid leukaemia (AML) was analysed with the APAAP technique using a panel of anti-myeloid and lymphoid associated monoclonal antibodies (McAb). Cells from all cases, including three with negative cytochemical features, were labelled by at least one of the anti-myeloid McAb CD13, anti-myeloperoxidase (anti-Mpo), and/or CD14. The most sensitive marker was CD13, since it was positive in 90% of cases. In two out of three AML cases defined as M0-AML, CD13 was expressed in the cytoplasm but not on the membrane; in these three cases peroxidase (Mpo) was not detected by conventional cytochemistry, but could be demonstrated in all of them using the McAb anti-Mpo. The simultaneous expression of CD14 and CD68 McAb was often confined to the M4 and M5 FAB AML subtypes (92% cases) as compared to the others: M1, M2, M3 (18% cases). Lymphoid antigens were rarely positive (TdT+: 13%, CD7+: 15%, CD19+: 5%) and none of the AML cases were CD3+ or CD10+. By contrast, CD4 was expressed in blasts from 44% of cases and this was not restricted to AML with a monocytic component (M4, M5) but also found in other subtypes. There were no significant differences in the clinical or prognostic features according to the positivity or negativity with TdT and CD4. By contrast, expression of CD7 was associated with refractoriness to the treatment or short complete remission duration, although the number of patients is too small to draw firm conclusions. Our findings support the clinical and diagnostic relevance of immunophenotypic studies in AML.     

Successful treatment by selective arterial embolization of severe retroperitoneal hemorrhage secondary to bone marrow biopsy in post-polycythemic myelofibrosis

Severe retroperitoneal hemorrhage represents an infrequent and serious complication of bone marrow biopsy. A 53-year-old man, diagnosed with polycythemia vera 12 years earlier, was submitted to a bone marrow biopsy due to the appearance of anemia with clinical and hematological features suggesting myelofibrotic transformation, a diagnosis that was confirmed by the marrow study. At 2 h of a right anterior iliac bone marrow trephine biopsy, the patient suddenly developed severe pain in the area of the biopsy, with antialgic flexion of the right leg. Computed tomographic (CT) scan of the abdomen showed a 5×9.5 cm hematoma in the right iliac and psoas muscles. The patient was initially managed with analgesics and transfusional support, but the pain persisted and a continuous fall in the hematocrit was observed in the following days. Angiographic examination of the right external iliac artery showed contrast extravasation arising from the circumflex iliac branch, which was embolized using polivinyl alcohol particles and one coil. Following such procedure, the patient recovered uneventfully and was discharged in good condition a few days later. This case illustrates the effectiveness of an endovascular approach in providing a fast and minimally invasive treatment for this life-threatening complication of bone marrow trephine biopsy.     

Is the histological classification of chronic granulocytic leukaemia justified from the clinical point of view?

By means of morphometric techniques, in 100 untreated Ph'-positive chronic granulocytic leukaemia (CGL) patients the main features from the initial bone marrow biopsy were analyzed, with particular attention being paid to morphological and quantitative study of megakaryocytes. The number of megakaryocytes per mm2 of marrow tissue showed a mean value of 25.3 (SD +/- 18.8), and was positively correlated with either platelet counts, blood percentage of basophils and blast cells, or spleen and liver size. Based on the number and morphological characteristics of megakaryocytes, patients were classified as having granulocytic CGL (67 cases) or the so-called chronic megakaryocytic-granulocytic myelosis (33 cases), but except for higher platelet counts and blood percentages of basophils and blast cells in the latter, no relevant clinical, evolutionary or prognostic differences were observed between the groups. Such results cast doubt on the validity of histological classification of CGL from the clinical point of view.     

Impact of response to treatment on survival in multiple myeloma: results in a series of 243 patients

Summary. Two hundred and forty-three patients diagnosed with multiple myeloma (MM) in a single institution over a 22-year period and treated with standard chemotherapy were analysed in an attempt to determine the impact of response to therapy on survival. The overall response rate in 229 evaluable patients was 50.1% (34.9% objective response plus 15.2% partial response). Median survivals of patients with objective and partial response were 43.4 and 42.8 months, respectively, versus 19 months for nonresponders. Median survival of 14 patients who achieved a complete remission was 42 months, whereas in 21 rapid responders (≤ 2 months) median survival was 43.3 months. A significant correlation between response and survival was observed with the landmark (P = 0.0169), the Mantel & Byar (P = 0.0001) and the Cox regression model (P < 0.0001) methods. These results indicate that, in responding patients, neither the degree of response nor the response kinetics has a significant influence on survival. However, the response to therapy is associated with a significantly longer survival in MM patients.