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71.
Water scarcity has become widespread all over the world. Current methods for water scarcity assessment are mainly based on water quantity and seldom consider water quality. Here, we develop a simple approach for assessing water scarcity considering both water quantity and quality. In this approach, a new water scarcity index is used to describe the severity of water scarcity in the form of a water scarcity meter, which may help to communicate water scarcity to a wider audience. To illustrate the approach, we analyzed the historical trend of water scarcity for Beijing city in China during 1995–2009. The results show that Beijing made a huge progress in mitigating water scarcity, and that from 1999 to 2009 the blue and grey water scarcity index decreased by 59% and 62%, respectively. These achievements were made through great efforts of water-saving measures and wastewater treatment. Despite this progress, we demonstrate that Beijing is still characterized by serious water scarcity due to both water quantity and quality. The water scarcity index remained at a high value of 3.5 with a blue and grey water scarcity index of 1.2 and 2.3 in 2009 (exceeding the thresholds of 0.4 and 1, respectively). As a result of unsustainable water use and pollution, groundwater levels continue to decline, and water quality shows a continuously deteriorating trend. To curb this trend, future water policies should further decrease water withdrawal from local sources (in particular groundwater) within Beijing, and should limit the grey water footprint below the total amount of water resources. 相似文献
72.
A test and calibration process for microcalorimeters is described. The method has been developed with particular reference to instruments used for measurements of thermal power produced by suspensions of living cells. The process investigated is the hydrolysis of triacetin in imidazole/acetic acid buffer. The power levels are regulated by changing the buffer composition. The power will decrease slowly and very nearly linearly with time. Five test solutions, power levels 7–90 μW·ml?1, have been characterized at 37°C and one of them at 25°C (13 μW·ml?1). The power values for these reaction mixtures can be accurately calculated (±0.5%) as a function of time during extended reaction periods, about 20 h or more. 相似文献
73.
《Endocrine practice》2023,29(7):538-545
ObjectiveTo assess the landscape of digital health resources in the United States, better understand the impact of the digital health on shared decision-making, and identify potential barriers and opportunities for progress in the care of persons with diabetes.MethodsThe study consisted of two phases: A qualitative phase in which one-on-one interviews were conducted virtually with 34 physicians (endocrinologists {Endos}: n = 15; primary care physicians {PCPs}: n = 19) between February 11, 2021 and February 18, 2021, and a quantitative phase in which two online, email-based surveys in the English language were conducted between April 16, 2021 and May 17, 2021: one with healthcare professionals (HCP) (n = 403: n = 200 Endos and n = 203 PCPs), and one with persons with diabetes (n = 517: patients with type 1 diabetes, n = 257; patients with type 2 diabetes, n = 260).ResultsDiabetes digital health tools were found to be helpful in shared decision-making, but leading barriers include cost, coverage, and lack of time by healthcare professionals. Among diabetes digital health tools, continuous glucose monitoring (CGM) systems were used most commonly and viewed as most effective in improving quality of life and facilitating shared decision-making. Strategies for increasing use of diabetes digital health resources included lower cost, integration into electronic health records, and increased simplicity of tools.ConclusionThis study revealed that both Endos and PCPs feel that diabetes digital health tools have an overall positive impact. Integration with telemedicine and simpler, lower cost tools with increased patient access can further facilitate shared decision-making and improved diabetes care and quality of life. 相似文献
74.
L. Guerra 《International journal of biometeorology》1988,32(1):11-16
The intensive discussion of the possible impact of atmospheric electricity in theInternational Journal of Biometeorology has motivated many physicians and scientists to include the respective measurements along with the assessment of the traditional parameters. The parameters most often required are: air ions, air-to-ground currents and the electrical earth potential. This paper is primarily concerned with a new generation of instruments to study such electrometeorological parameters, particularly air ionization. This paper describes the key data and functions of the Ion-Meter PN-2001 the first result of a mid-term development plan; the Meteoline uP-2000. The latter is a group of five new instruments for the study of electro-atmospheric parameters. 相似文献
75.
A small, lightweight meter has been developed for magnetic-field measurements, particularly those needed for exposure-assessment purposes. This meter, known as the AMEX-3D, continuously measures all three axes of magnetic-flux density and electronically combines the data into a single estimate of cumulative exposure to the root-mean-square (rms) resultant flux density. The AMEX-3D weighs about 120 g, measures 2.7 cm x 5.1 cm x 10.2 cm, and is battery powered. Two panel-mounted jacks are provided for measuring battery voltage and for reading cumulative exposure data from the unit. The instrument has, within 3 dB, a flat response to magnetic flux densities at all frequencies in its 30-1,000 Hz bandwidth. A detailed analysis of error sources in the AMEX-3D leads to an estimate of +/- 20% as the accuracy of the instrument over its dynamic range, which extends from 0.02 to 15 microT. The AMEX-3D was tested in the field by asking electric-utility distribution linemen to wear AMEX-3D and EMDEX meters simultaneously while working. Agreement between the two measures of exposure was excellent. 相似文献
76.
Power density and duty factor values were measured around smart utility meters operating at 868 MHz under laboratory-controlled conditions. The maximum 6-min averaged exposure recorded was 0.1 mWm−2, which is less than 0.0024% of the corresponding 1998 ICNIRP general public reference level. Duty factors measured were less than 2.8%. This study found that the exposure contribution from Zigbee smart meter devices operating at 868 MHz is generally lower than, if not similar to, those operating at 2.4 GHz. © 2023 Crown copyright. Bioelectromagnetics published by Wiley Periodicals LLC on behalf of Bioelectromagnetics Society. 相似文献