scholarly journals Long-period solar annual and semiannual tidal contributions to the lowest normal low water in seas surrounding China

2021 ◽  
Author(s):  
Yanguang Fu ◽  
Dongxu Zhou ◽  
Yikai Feng ◽  
Xinghua Zhou

Abstract. As the chart datum of China, the lowest normal low water (LNLW) was calculated using three tidal constituents, major (Q1, O1, P1, K1, N2, M2, S2 and K2), shallow water (M4, MS4 and M6) and long-period tidal (Sa and Ssa). The construction of a tidal datum is mainly concerned with improvements in the major tidal constituents, and the contribution of the long-period tidal component has been generally neglected. In this study, long-term tide gauge observations and multi-mission satellite altimetry data were used to investigate the spatial distribution of the long-period tidal contribution in Chinese seas and analyze the relative long-period tidal contribution rate into four regions. The results showed that the mean contribution in Chinese seas is 7.63 %, with the largest contribution in the Bohai Sea (11.33 %) and smallest in the East China Sea (5.27 %). Differences between tide gauge and satellite-derived results were compared in detail. The Sa and M2 tidal amplitudes are the main factors affecting the long-period tidal contribution to the LNLW. The relative long-period tidal contribution can be up to 34.18 % when tide gauge observations record small M2 and large Sa amplitudes. These results indicate that the long-period tidal constituent cannot be neglected in the establishment of the LNLW datum. Therefore, to improve tidal datum precision, precise extraction and accuracy assessments of long-period tidal constituents should be a research focus.

2008 ◽  
Vol 4 (S259) ◽  
pp. 237-238 ◽  
Author(s):  
Nadezhda V. Zolotova ◽  
D. I. Ponyavin

AbstractThe long-term records of sunspot area available separately for Northern and Southern Hemispheres have been investigated by means of cross-recurrence technique. Phase component of the north-south asymmetry was extracted. This measure demonstrates long-period systematic variations with the sign change of hemispheric leading in 1930s and 1960s. Moreover phase north-south asynchrony anticorrelates with the so called magnetic equator, which was defined as difference of the mean sunspot latitudes between two hemispheres. Relationships of the phase north-south asynchrony, magnetic equator and butterfly diagrams are presented and discussed.


2020 ◽  
Vol 12 (12) ◽  
pp. 1945
Author(s):  
Liqiao Tian ◽  
Xianghan Sun ◽  
Jian Li ◽  
Qianguo Xing ◽  
Qingjun Song ◽  
...  

Satellite-based ocean color sensors have provided an unprecedentedly large amount of information on ocean, coastal and inland waters at varied spatial and temporal scales. However, observations are often adversely affected by cloud coverage and other poor weather conditions, like sun glint, and this influences the accuracy associated with long-term monitoring of water quality parameters. This study uses long-term (2013–2017) and high-frequency (eight observations per day) datasets from the Geostationary Ocean Color Imager (GOCI), the first geostationary ocean color satellite sensor, to quantify the cloud coverage over China’s seas, the resultant interrupted observations in remote sensing, and their impacts on the retrieval of total suspended sediments (TSS). The monthly mean cloud coverage for the East China Sea (ECS), Bohai Sea (BS) and Yellow Sea (YS) were 62.6%, 67.3% and 69.9%, respectively. Uncertainties regarding the long-term retrieved TSS were affected by a combination of the effects of cloud coverage and TSS variations. The effects of the cloud coverage dominated at the monthly scale, with the mean normalized bias (Pbias) at 14.1% (±2.6%), 7.6% (±2.3%) and 12.2% (±4.3%) for TSS of the ECS, BS and YS, respectively. Cloud coverage-interfering observations with the Terra/Aqua MODIS systems were also estimated, with monthly Pbias ranging from 6.5% (±7.4%) to 20% (±13.1%) for TSS products, and resulted in a smaller data range and lower maximum to minimum ratio compared to the eight GOCI observations. Furthermore, with approximately 16.7% monthly variations being missed during the periods, significant “missing trends” effects were revealed in monthly TSS variations from Terra/Aqua MODIS. For the entire region and the Bohai Sea, the most appropriate timeframe for sampling ranges from 12:30 to 15:30, while this timeframe was narrowed to from 13:30 to 15:30 for observations in the East China Sea and the Yellow Sea. This research project evaluated the effects of cloud coverage and times for sampling on the remote sensing monitoring of ocean color constituents, which would suggest the most appropriate timeframe for ocean color sensor scans, as well as in situ data collection, and can provide design specification guidance for future satellite sensor systems.


2013 ◽  
Vol 88 (3) ◽  
pp. 207-222 ◽  
Author(s):  
Alvaro Santamaría-Gómez ◽  
Médéric Gravelle ◽  
Guy Wöppelmann

Author(s):  
L. Rickards ◽  
A. Matthwes ◽  
K. Gordon ◽  
M. Tamisea ◽  
S. Jevrejeva ◽  
...  

Abstract. The PSMSL was established as a “Permanent Service” of the International Council for Science in 1958, but in practice was a continuation of the Mean Sea Level Committee which had been set up at the Lisbon International Union of Geodesy and Geophysics (IUGG) conference in 1933. Now in its 80th year, the PSMSL continues to be the internationally recognised databank for long-term sea level change information from tide gauge records. The PSMSL dataset consists of over 2100 mean sea level records from across the globe, the longest of which date back to the start of the 19th century. Where possible, all data in a series are provided to a common benchmark-controlled datum, thus providing a record suitable for use in time series analysis. The PSMSL dataset is freely available for all to use, and is accessible through the PSMSL website (www.psmsl.org).


2020 ◽  
Vol 8 (37) ◽  
pp. 1-248
Author(s):  
Fiona Lobban ◽  
Duncan Appelbe ◽  
Victoria Appleton ◽  
Golnar Aref-Adib ◽  
Johanna Barraclough ◽  
...  

Background Digital health interventions have the potential to improve the delivery of psychoeducation to people with mental health problems and their relatives. Despite substantial investment in the development of digital health interventions, successful implementation into routine clinical practice is rare. Objectives Use the implementation of the Relatives’ Education And Coping Toolkit (REACT) for psychosis/bipolar disorder to identify critical factors affecting uptake and use, and develop an implementation plan to support the delivery of REACT. Design This was an implementation study using a mixed-methods, theory-driven, multiple case study approach. A study-specific implementation theory for REACT based on normalisation process theory was developed and tested, and iterations of an implementation plan to address the key factors affecting implementation were developed. Setting Early-intervention teams in six NHS mental health trusts in England (three in the north and three in the south). Participants In total, 281 staff accounts and 159 relatives’ accounts were created, 129 staff and 23 relatives took part in qualitative interviews about their experiences, and 132 relatives provided demographic data, 56 provided baseline data, 21 provided data at 12 weeks’ follow-up and 20 provided data at 24 weeks’ follow-up. Interventions REACT is an online supported self-management toolkit, offering 12 evidence-based psychoeducation modules and support via a forum, and a confidential direct messaging service for relatives of people with psychosis or bipolar disorder. The implementation intervention was developed with staff and iteratively adapted to address identified barriers. Adaptations included modifications to the toolkit and how it was delivered by teams. Main outcome measures The main outcome was factors affecting implementation of REACT, assessed primarily through in-depth interviews with staff and relatives. We also assessed quantitative measures of delivery (staff accounts and relatives’ invitations), use of REACT (relatives’ logins and time spent on the website) and the impact of REACT [relatives’ distress (General Health Questionnaire-28), and carer well-being and support (Carer Well-being and Support Scale questionnaire)]. Results Staff and relatives were generally positive about the content of REACT, seeing it as a valuable resource that could help services improve support and meet clinical targets, but only within a comprehensive service that included face-to-face support, and with some additional content. Barriers to implementation included high staff caseloads and difficulties with prioritising supporting relatives; technical difficulties of using REACT; poor interoperability with trust information technology systems and care pathways; lack of access to mobile technology and information technology training; restricted forum populations leading to low levels of use; staff fears of managing risk, online trolling, or replacement by technology; and uncertainty around REACT’s long-term availability. There was no evidence that REACT would reduce staff time supporting relatives (which was already very low), and might increase it by facilitating communication. In all, 281 staff accounts were created, but only 57 staff sent relatives invitations. In total, 355 relatives’ invitations were sent to 310 unique relatives, leading to the creation of 159 relatives’ accounts. The mean number of logins for relatives was 3.78 (standard deviation 4.43), but with wide variation from 0 to 31 (median 2, interquartile range 1–8). The mean total time spent on the website was 40.6 minutes (standard deviation 54.54 minutes), with a range of 0–298 minutes (median 20.1 minutes, interquartile range 4.9–57.5 minutes). There was a pattern of declining mean scores for distress, social dysfunction, depression, anxiety and insomnia, and increases in relatives’ well-being and eHealth literacy, but no changes were statistically significant. Conclusions Digital health interventions, such as REACT, should be iteratively developed, evaluated, adapted and implemented, with staff and service user input, as part of a long-term strategy to develop integrated technology-enabled services. Implementation strategies must instil a sense of ownership for staff and ensure that they have adequate training, risk protocols and resources to deliver the technology. Cost-effectiveness and impact on workload and inequalities in accessing health care need further testing, along with the generalisability of our findings to other digital health interventions. Limitations REACT was offered by the same team running the IMPlementation of A Relatives’ Toolkit (IMPART) study, and was perceived by staff and relatives as a time-limited research study rather than ongoing clinical service, which affected engagement. Access to observational data was limited. Trial registration Current Controlled Trials ISRCTN16267685. Funding This project was funded by the National Institute for Health Research (NIHR) Health Services and Delivery Research programme and will be published in full in Health Services and Delivery Research; Vol. 8, No. 37. See the NIHR Journals Library website for further project information.


2020 ◽  

Background: Patients with mechanical heart valve replacement surgery (MHVRS) should be followed up in terms of prosthetic valve-related and open heart surgery complications. This study aimed to determine the anticoagulant complications in long term in patients with MHVRS. Methods: This retrospective and descriptive study was conducted in a university hospital, İzmir, Turkey. The data were collected from July to December 2019. In total, 73 patients referring for regular check-ups to the hospital with intervals not exceeded more than 90 days, and those who had international normalized ratio (INR) measurements for January-April-July-October 2018 were included in this study. Results: The mean age of the patients was obtained at 58.98±12.89 years, and 53.4% (n=39) of the cases were male. Moreover, the mean follow-up period was estimated at 65.98±28.47 months. According to the results, complications developed in 60 patients (82.2%). The first hospitalized unit was the emergency department. The factors affecting the development of complications after MHVRS were evaluated, and a difference was found regarding gender (X2=6.18, P=0.013), comorbidities (X2=25.58, P=0.018), and monthly referral for regular check-ups to the hospital (X2=5.20, P=0.023). There was no relationship between the INR levels and the development of complications. Furthermore, the results of evaluating the factors affecting the number of hospitalizations after MHVRS revealed that monthly referral to hospital for check-ups (t=3.18, P=0.002) and history of previous valve surgery (Z=201.00, P=0.03) affected the number of hospitalizations. Conclusions: It was observed that patients frequently refer to the emergency department and struggled with various complications. Moreover, it was found that the patients had frequent bleeding and refer to the emergency service repeatedly. Accordingly, there is a need for interventional studies to reduce postoperative complications and provide the therapeutic INR level.


2007 ◽  
Vol 15 (4) ◽  
pp. 324-326 ◽  
Author(s):  
Yee Jim Loh ◽  
Masakazu Nakao ◽  
Wei Ding Tan ◽  
Chong Hee Lim ◽  
Yong Seng Tan ◽  
...  

Size matching of radial artery conduits to coronary arteries is important as it affects the long-term patency. However, factors affecting radial artery size have not been adequately investigated. We retrospectively reviewed 327 consecutive patients who had duplex ultrasonography of their radial arteries over a 2-year period. There were 225 men and 102 women. The mean radial artery size was 2.45 ± 0.54 mm. The factors found to positively affect the size of the radial artery were sex, hypertension, and hyperlipidemia. Diabetes mellitus and age were found to negatively affect radial artery size. Renal disease, race, and smoking did not significantly influence the size of the radial artery. However, as the R squared of this model was insignificant, further studies need to be undertaken to determine other factors that may influence radial artery size.


2020 ◽  
Vol 32 (1) ◽  
pp. 89-97
Author(s):  
Shaohui He ◽  
Yuduo Xu ◽  
Jialin Li ◽  
Yue Zhang ◽  
Haifeng Wei ◽  
...  

OBJECTIVELeiomyogenic tumor of the spine is rare with limited published information. Here, the authors report the clinical features and long-term surgical outcomes and investigate the prognostic factors affecting disease-free survival (DFS).METHODSTwelve patients presented to the authors’ institution for surgical treatment from January 2005 to December 2018. The clinical characteristics and outcomes were retrospectively reviewed, and the DFS rate was estimated using the Kaplan-Meier method. The log-rank test was used to identify the potential prognostic factors, with p < 0.05 considered statistically significant.RESULTSThe mean patient age was 49.7 ± 12.9 years (range 22–73 years). Four patients underwent marginal en bloc resection, and 8 patients underwent conventional piecemeal resection. Pathological diagnosis revealed leiomyosarcoma in 9 patients and leiomyoma in 3 patients. Three patients had tumor recurrence at a mean follow-up of 10.4 months (range 7.0–15.0 months), while 4 developed metastases at an average of 13.8 months (range 5.5–21.3 months) postoperatively. During the mean follow-up of 33.7 months (range 9.6–78.5 months), the estimated 1- and 5-year DFS rates were 66.7% and 38.2%, respectively. Albumin loss > 20 g/L after surgery, Ki-67 positivity > 10%, and piecemeal resection were correlated with worse DFS.CONCLUSIONSSurgical management of spinal leiomyogenic tumors is challenging due to the high rate of recurrence and metastases. En bloc resection should be performed in eligible patients. Albumin loss > 20 g/L and the Ki-67 index may be independent factors affecting prognosis.


2021 ◽  
Vol 11 (1) ◽  
pp. 139
Author(s):  
Agata Gabryelska ◽  
Marcin Sochal ◽  
Bartosz Wasik ◽  
Przemysław Szczepanowski ◽  
Piotr Białasiewicz

Continuous positive airway pressure (CPAP) has been the standard treatment of obstructive sleep apnoea/hypopnoea syndrome (OSA) for almost four decades. Though usually effective, this treatment suffers from poor long-term compliance. Therefore, the aim of our one centre retrospective study was to assess factors responsible for treatment failure and long-term compliance. Four hundred subsequent patients diagnosed with OSA and qualified for CPAP treatment were chosen from our database and compliance data were obtained from medical charts. Many differing factors kept patients from starting CPAP or led to termination of treatment. Overall, almost half of patients ended treatment during the mean time of observation of 3.5 years. Survival analysis revealed that 25% of patients failed at a median time of 38.2 months. From several demographic and clinical covariates in Cox’s hazard model, only the presence of a mild OSA, i.e., AHI (apnoea/hypopnoea index) below 15/h was a factor strongly associated with long term CPAP failure. The compliance results of our study are in line with numerous studies addressing this issue. Contrary to them, some demographic or clinical variables that we used in our survival model were not related to CPAP adherence.


2021 ◽  
Vol 103-B (11) ◽  
pp. 1648-1655
Author(s):  
Soo-Young Jeong ◽  
Kyu-Tae Hwang ◽  
Chang-Wug Oh ◽  
Joon-Woo Kim ◽  
Oog Jin Sohn ◽  
...  

Aims The incidence of atypical femoral fractures (AFFs) continues to increase. However, there are currently few long-term studies on the complications of AFFs and factors affecting them. Therefore, we attempted to investigate the outcomes, complications, and risk factors for complication through mid-term follow-up of more than three years. Methods From January 2003 to January 2016, 305 patients who underwent surgery for AFFs at six hospitals were enrolled. After exclusion, a total of 147 patients were included with a mean age of 71.6 years (48 to 89) and 146 of whom were female. We retrospectively evaluated medical records, and reviewed radiographs to investigate the fracture site, femur bowing angle, presence of delayed union or nonunion, contralateral AFFs, and peri-implant fracture. A statistical analysis was performed to identify the significance of associated factors. Results The mean follow-up period was 70.2 months (36 to 191). There were 146 AFFs (99.3%) in female patients and the mean age was 71.6 years (48 to 89). The AFFs were located in the subtrochanter and shaft in 52 cases (35.4%) and 95 (64.6%), respectively. The preoperative mean anterior/lateral femoral bowing angles were 10.5° (SD 5.7°)/6.1° (SD 6.2°). The postoperative mean anterior/lateral bowing values were changed by 8.7° (SD 5.4°)/4.6° (SD 5.9°). Bisphosphonates had been used contemporarily in 115 AFFs (78.2%) for a mean of 52.4 months (1 to 204; SD 45.5) preoperatively. Nailing was performed in 133 AFFs (90.5%), and union was obtained at a mean of 23.6 weeks (7 to 85). Delayed union occurred in 41 (27.9%), and nonunion occurred in 13 (8.8%). Contralateral AFF occurred in 79 patients (53.7%), and the use of a bisphosphonate significantly influenced the occurrence of contralateral AFFs (p = 0.019). Peri-implant fractures occurred in a total of 13 patients (8.8%), and a significant increase was observed in cases with plating (p = 0.021) and high grade of postoperative anterolateral bowing (p = 0.044). Conclusion The use of a bisphosphonate was found to be a risk factor for contralateral AFF, and high-grade postoperative anterolateral bowing and plate fixation significantly increased the occurrence of peri-implant fractures. Long-term follow-up studies on the bilaterality of AFFs and peri-implant fractures are warranted. Cite this article: Bone Joint J 2021;103-B(11):1648–1655.


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