Background: Gastroesophageal reflux disease (GERD) is a prevalent disease in Western countries. Despite effective treatment modalities, in some patients total symptom control is not achieved in clinical practice. A cr...Background: Gastroesophageal reflux disease (GERD) is a prevalent disease in Western countries. Despite effective treatment modalities, in some patients total symptom control is not achieved in clinical practice. A cross-sectional study was designed to assess primary care practitioners’ views on the effectiveness of proton pump inhibitors (PPI) as monotherapy in the control of the most common symptoms of GERD (heartburn and regurgitation), as well as to determine the level of implementation of the “combined therapy” (PPI + alginate-antacids). Methods: A questionnaire on different aspects of the management of GERD was completed by 1491 primary care physicians. The questionnaire was composed of 11 close-ended questions with one-choice answer, with a total of 52 items, covering the main data from patients presenting with GERD. Results: Treatment with PPI alone was mostly considered insufficient for the control of GERD symptoms. The combined treatment of PPI + alginate-antacids was used for 37% and 21% of physicians for treating heart-burn and regurgitation, respectively. A better control of symptoms, an increase in the onset of action and to reduce nocturnal acid breakthrough were the most frequently argued reasons for the use of PPI + alginate-antacids. A high percentage of participants believed that treatment with PPI alone was insufficient for the control of symptoms and 39.8% of physicians reported the persistence of heartburn, 38.6% the persistence of regurgitation and 43.2% the persistence of epigastric discomfort in more than 25% of their patients treated with PPI as monotherapy. The most common schedule for the use of the antacid medication was on demand. Conclusions: Spanish primary care physicians consider that a high proportion of GERD patients continue to suffer from symptoms during PPI treatment alone. Ondemand “combined therapy” (PPI + antacid) is considered an efficient option to control reflux symptoms still troublesome in patients with PPI treatment alone.展开更多
A Geothermal Heat Pump (GHP) system is known to have enormous potential for building energy savings and the reduction of associated greenhouse gas emissions, due to its high Coefficient Of Performance (COP). The use o...A Geothermal Heat Pump (GHP) system is known to have enormous potential for building energy savings and the reduction of associated greenhouse gas emissions, due to its high Coefficient Of Performance (COP). The use of a GHP system in cold-climate regions is more attractive owing to its higher COP for heating compared to conventional heating devices, such as furnaces or boilers. Many factors, however, determine the operational performance of an existing GHP system, such as control strategy, part/full-load efficiency, the age of the system, defective parts, and whether or not regular maintenance services are provided. The omitting of any of these factors in design and operation stages could have significant impacts on the normal operation of GHP systems. Therefore, the objectives of this paper are to further investigate and study the existing GHP systems currently used in buildings located in cold-climate regions of the US, in terms of system operational performance, potential energy and energy cost savings, system cost information, the reasons for installing geothermal systems, current operating difficulties, and owner satisfaction to date. After the comprehensive investigation and in-depth analysis of 24 buildings, the results indicate that for these buildings, about 75% of the building owners are very satisfied with their GHP systems in terms of noise, cost, and indoor comfort. About 71% of the investigated GHP systems have not had serious operating difficulties, and about 85% of the respondents (building owners) would suggest this type of system to other people. Compared to the national median of energy use and energy cost of typical buildings of the same type nationwide, the overall performance of the actual GHP systems used in the cold-climate regions is slightly better, i.e. about 7.2% energy savings and 6.1% energy cost savings on average.展开更多
A dual-band bandpass microwave photonic filter(MPF) based on stimulated Brillouin scattering(SBS) is theoretically analyzed and experimentally demonstrated. Two separated tunable laser sources(TLSs) are employed to ge...A dual-band bandpass microwave photonic filter(MPF) based on stimulated Brillouin scattering(SBS) is theoretically analyzed and experimentally demonstrated. Two separated tunable laser sources(TLSs) are employed to generate two passbands by implementing phase modulation to amplitude modulation conversion by using SBS induced sideband amplification. The center frequencies of both passbands can be independently tuned ranging from 1 GHz to 19 GHz. High resolution with 3 d B bandwidth less than 30 MHz and large out-of-band rejection about 40 d B under 25 m W optical pump power are achieved.展开更多
文摘Background: Gastroesophageal reflux disease (GERD) is a prevalent disease in Western countries. Despite effective treatment modalities, in some patients total symptom control is not achieved in clinical practice. A cross-sectional study was designed to assess primary care practitioners’ views on the effectiveness of proton pump inhibitors (PPI) as monotherapy in the control of the most common symptoms of GERD (heartburn and regurgitation), as well as to determine the level of implementation of the “combined therapy” (PPI + alginate-antacids). Methods: A questionnaire on different aspects of the management of GERD was completed by 1491 primary care physicians. The questionnaire was composed of 11 close-ended questions with one-choice answer, with a total of 52 items, covering the main data from patients presenting with GERD. Results: Treatment with PPI alone was mostly considered insufficient for the control of GERD symptoms. The combined treatment of PPI + alginate-antacids was used for 37% and 21% of physicians for treating heart-burn and regurgitation, respectively. A better control of symptoms, an increase in the onset of action and to reduce nocturnal acid breakthrough were the most frequently argued reasons for the use of PPI + alginate-antacids. A high percentage of participants believed that treatment with PPI alone was insufficient for the control of symptoms and 39.8% of physicians reported the persistence of heartburn, 38.6% the persistence of regurgitation and 43.2% the persistence of epigastric discomfort in more than 25% of their patients treated with PPI as monotherapy. The most common schedule for the use of the antacid medication was on demand. Conclusions: Spanish primary care physicians consider that a high proportion of GERD patients continue to suffer from symptoms during PPI treatment alone. Ondemand “combined therapy” (PPI + antacid) is considered an efficient option to control reflux symptoms still troublesome in patients with PPI treatment alone.
文摘A Geothermal Heat Pump (GHP) system is known to have enormous potential for building energy savings and the reduction of associated greenhouse gas emissions, due to its high Coefficient Of Performance (COP). The use of a GHP system in cold-climate regions is more attractive owing to its higher COP for heating compared to conventional heating devices, such as furnaces or boilers. Many factors, however, determine the operational performance of an existing GHP system, such as control strategy, part/full-load efficiency, the age of the system, defective parts, and whether or not regular maintenance services are provided. The omitting of any of these factors in design and operation stages could have significant impacts on the normal operation of GHP systems. Therefore, the objectives of this paper are to further investigate and study the existing GHP systems currently used in buildings located in cold-climate regions of the US, in terms of system operational performance, potential energy and energy cost savings, system cost information, the reasons for installing geothermal systems, current operating difficulties, and owner satisfaction to date. After the comprehensive investigation and in-depth analysis of 24 buildings, the results indicate that for these buildings, about 75% of the building owners are very satisfied with their GHP systems in terms of noise, cost, and indoor comfort. About 71% of the investigated GHP systems have not had serious operating difficulties, and about 85% of the respondents (building owners) would suggest this type of system to other people. Compared to the national median of energy use and energy cost of typical buildings of the same type nationwide, the overall performance of the actual GHP systems used in the cold-climate regions is slightly better, i.e. about 7.2% energy savings and 6.1% energy cost savings on average.
基金supported by the Science and Technology Development Plan of Jilin Province(Nos.20150204003GX and 20160519010JH)the Science and Technology Plan of Changchun(No.14KG019)
文摘A dual-band bandpass microwave photonic filter(MPF) based on stimulated Brillouin scattering(SBS) is theoretically analyzed and experimentally demonstrated. Two separated tunable laser sources(TLSs) are employed to generate two passbands by implementing phase modulation to amplitude modulation conversion by using SBS induced sideband amplification. The center frequencies of both passbands can be independently tuned ranging from 1 GHz to 19 GHz. High resolution with 3 d B bandwidth less than 30 MHz and large out-of-band rejection about 40 d B under 25 m W optical pump power are achieved.