High‐resolution observations of the currents, hydrography, and turbulence within internal solitary waves (ISWs) reveal Kelvin‐Helmholtz (KH) billows and breaking waveforms occurring in the lower ...periphery and in the trailing edges, respectively, of the wave cores. Marginal instability (MI) is evident in wave cores, where the probability distribution of the Richardson number Ri, fluctuates around 0.25. The critical value for the occurrence of KH instability in ISWs is evidently 0.25, the canonical criterion of a parallel stratified shear flow. When Ri > 0.25, the turbulent diffusivity Κρ remains O (10−3) m2 s−1 with a standard deviation of one order. When Ri crosses the critical value, the logarithmic turbulent diffusivity linearly increases with a logarithmic reduction in Ri to smooth the velocity and density differences so that Ri is ultimately restored to >0.25. Therefore, the processes of MI cycling preserve ISWs against breakdowns resulting from the uninterrupted growth of KH instability.
Plain Language Summary
High‐resolution observations of solitary waves in the ocean interior show the instability induced by the roll‐up of the water layer and the waveform breaking around the wave core. The occurrence of roll‐up depends on the ratio between the magnitude of stratification and velocity shear, with a critical value of 1/4. If the magnitude of the shear is 4 times larger than that of the stratification, roll‐up of the water layer occurs. Our observations reveal a balanced status within the wave core; that is, statistically, the value of the above ratio oscillates around 1/4. This is caused by the shear‐induced roll‐up of the water layer when the ratio is <1/4, which can eventually evolve into turbulence. The turbulence then weakens the shear and stratification and consequently brings the ratio back to >1/4. This cyclic process could preserve the interior waves against breakdowns resulting from uninterrupted roll‐ups.
Key Points
Marginal instability is evident in the cores of internal solitary waves
The observations suggest that the critical value for the occurrence of shear instability in Internal solitary waves (ISWs) is 0.25
Marginal instability is a cyclic process that preserves ISWs against breakdowns resulting from uninterrupted Kelvin‐Helmholtz (KH) instability growth
Trains of large Kelvin‐Helmholtz (KH) billows within the Kuroshio current at ~230 m depth off southeastern Taiwan and above a seamount were observed by shipboard instruments. The trains of large KH ...billows were present in a strong shear band along the 0.55 m s−1 isotach within the Kuroshio core; they are presumably produced by flow interactions with the rapidly changing topography. Each individual billow, resembling a cat's eye, had a horizontal length scale of 200 m, a vertical scale of 100 m, and a timescale of 7 min, near the local buoyancy frequency. Overturns were observed frequently in the billow cores and the upper eyelids. The turbulent kinetic energy dissipation rates estimated using the Thorpe scale had an average value of O(10−4) W kg−1 and a maximum value of O(10−3) W kg−1. The turbulence mixing induced by the KH billows may exchange Kuroshio water with the surrounding water masses.
Key Points
Large KH billows induced by flow‐seamount interactions were observed within the Kuroshio core
The KH billows produce energetic and persistent turbulent mixing in the Kuroshio stream
Properly parameterizing small‐scale processes in simulations of the Kuroshio is needed
Background
This study investigated breast cancer‐related lymphedema (BCRL) and its correlation with the incidence of cellulitis and mortality in the National Health Insurance (NHI) database in ...Taiwan.
Methods
Between 2004 and 2014, the NHI database of patients with breast cancer who underwent surgical procedures, adjuvant therapies, BCRL, cellulitis, and mortality were retrospectively reviewed. Cox regression was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for incidence of BCRL and cellulitis in different treatment groups. The associations of BCRL with the incidence of cellulitis and mortality were further analyzed using the Kaplan–Meier curve.
Results
Among 100 301 patients, 5464 (5.4%) developed BCRL with a median onset of 1.3 years. At a mean follow‐up of 4.77 years, the incidence of cellulitis in the BCRL group (12.7%, 694/5464 patients) was significantly higher than in the no‐BCRL group (2.73%, 2589/94 837 patients) (HR: 3.74; 95% CI: 3.43–4.08; p < 0.0001). At a mean follow‐up of 5.77 years, the mortality rate in the cellulitis group (34.21%, 1123/3283 patients) was significantly greater than in the no‐cellulitis group (16.29%, 15 804/97 018 patients) (HR: 1.17; 95% CI: 1.1–1.24; p < 0.0001).
Conclusions
BCRL had a significantly higher incidence of cellulitis and mortality.
At the heart of the entrepreneurial process in creative industries are entrepreneurial creativity and opportunity recognition, which influence entrepreneurs’ ability to create new ventures or ...significantly improve the position of an existing business. Recent entrepreneurship research has suggested that resource availability represents a double-edged sword, simultaneously facilitating and impeding new venture outcomes, while little research has explored how entrepreneurial creativity, opportunity recognition, and resource availability jointly affect entrepreneurial career success. To address the theoretical gap, this paper examines the moderating role of resource availability in the relationship between entrepreneurial creativity, opportunity recognition and career success of creative entrepreneurs.
To reflect the career success perceived by business founders in creative industries, five indicators of entrepreneurial success are examined, including career achievement, social reputation, entrepreneurial happiness, capability enhancement, and financial satisfaction. Hierarchical regression analysis empirically examines a sample of 296 entrepreneurs in creative industries. Results suggest that entrepreneurial creativity and opportunity recognition are positively related to entrepreneurial career success. We also find that resource availability generally strengthens the effect of entrepreneurial creativity and opportunity recognition on entrepreneur-perceived career success. Nevertheless, the relationship between opportunity recognition and financial satisfaction is found to be weakened by entrepreneurs’ resource availability. Integrating the theory of entrepreneurial effectuation and resource dependence theory, our findings indicate that entrepreneurial bricolage is crucial for creative entrepreneurship.
OBJECTIVE:The aim was to validate the new Taiwan Lymphoscintigraphy Staging, correlate it with Cheng Lymphedema Grading (CLG) and evaluate the treatment outcomes of unilateral extremity lymphedema.
...BACKGROUND:No consensus has been reached for diagnosis and staging for patients with lymphedema among medical specialties.
METHODS:We included 285 patients with unilateral extremity lymphedema using lymphoscintigraphy. Lymphoscintigraphy was correlated to clinical symptoms and signs, and classified into normal lymphatic drainage, partial obstruction, and total obstruction. Inter- and intraobserver reliability of Taiwan Lymphoscintigraphy Staging, correlation between Taiwan Lymphoscintigraphy Staging and clinical findings were conducted. Patients were categorized in “surgical” (n = 154) or “nonsurgical” (n = 131) groups for outcome evaluation.
RESULTS:Lymphoscintigraphy found 11 patients (3.9%) with normal lymphatic drainage, 128 (44.9%) with partial obstruction, and 146 (51.2%) with total obstruction. Taiwan Lymphoscintigraphy Staging showed high interobserver agreement intraclass correlation coefficient0.89 (95% confidence interval, 0.82–0.94), and significantly correlated to computed tomography volumetric difference (r = 0.66, P < 0.001) and CLG intraclass correlation coefficient0.79 (95% confidence interval 0.72–0.84). At a mean follow-up of 31.2 ± 2.9 months, significant improvement in the circumferential difference (from 23.9% ± 17.6% to 14.6% ± 11.1%; P = 0.03) with a mean circumferential reduction rate of 40.4% ± 4.5% was found in surgical group. At a mean follow-up of 26.6 ± 8.7 months, the nonsurgical group had increase of mean circumferential difference from 24.0% ± 17.2% to 25.3% ± 19.0% (P = 0.09), with a mean circumferential reduction rate was −1.9% ± 13.0%.
CONCLUSIONS:The Taiwan Lymphoscintigraphy Staging is a reliable diagnostic tool, correlated with clinical findings and CLG, aiding in the selection of the appropriate treatment to achieve favorable long-term outcomes in unilateral extremity lymphedema.
This study aimed to conduct a systematic review and meta-analysis comparing the effect of video-assistance and audio-assistance on quality of dispatcher-instructed cardiopulmonary resuscitation ...(DI-CPR) for bystanders.
Five databases were searched, including PubMed, Cochrane library, Embase, Scopus and NIH clinical trial, to find randomized control trials published before June 2017. Qualitative analysis and meta-analysis were undertaken to examine the difference between the quality of video-instructed and audio-instructed dispatcher-instructed bystander CPR.
The database search yielded 929 records, resulting in the inclusion of 9 relevant articles in this study. Of these, 6 were included in the meta-analysis. Initiation of chest compressions was slower in the video-instructed group than in the audio-instructed group (median delay 31.5 s; 95% CI: 10.94–52.09). The difference in the number of chest compressions per minute between the groups was 19.9 (95% CI: 10.50–29.38) with significantly faster compressions in the video-instructed group than in the audio-instructed group (104.8 vs. 80.6). The odds ratio (OR) for correct hand positioning was 0.8 (95% CI: 0.53–1.30) when comparing the audio-instructed and video-instructed groups. The differences in chest compression depth (mm) and time to first ventilation (seconds) between the video-instructed group and audio-instructed group were 1.6 mm (95% CI: −8.75, 5.55) and 7.5 s (95% CI: −56.84, 71.80), respectively.
Video-instructed DI-CPR significantly improved the chest compression rate compared to the audio-instructed method, and a trend for correctness of hand position was also observed. However, this method caused a delay in the commencement of bystander-initiated CPR in the simulation setting.
The hands‐on supermicrosurgery course provided participants a valuable learning experience of in‐depth practices of supermicrosurgical skills with experts. Seven live surgeries were successfully ...demonstrated at 8th World Symposium for Lymphedema Surgery. Variable donor sites for vascularized lymph node transfer were the submental, supraclavicular, groin, and omental; while the recipient sites included the wrist and axilla in upper limb; and popliteal and groin in the lower limb. The therapeutic and preventive lymphovenous anastomosis was also satisfactorily performed.
Chinese entrepreneurs cultivate and mobilize their guanxi networks to acquire information and resources for new ventures. Entrepreneurs in creative industries tend to suffer from especially high ...failure rates, but prior research pays little attention to understand whether or not creative entrepreneurs' guanxi networks help overcome obstacles in entrepreneurial activities. Through testing a sample of 293 creative entrepreneurs, this study examines the impact of entrepreneurs' four types of guanxi networks, namely family ties, business ties, community ties, and government ties. The findings reveal that guanxi networks indeed influence entrepreneurial success through the mediating effects of information accessibility and resource availability. Specifically, findings suggest that family ties, business ties, and community ties improve information accessibility, whereas family ties and government ties enhance resource availability.
The existing research contributes to our understanding about the value of social capital in a wide range of social science disciplines; however, it does not well address the role of social capital in ...creativity for research and development (R&D) project teams in a given context. Using a sample of 54 R&D project teams in high‐technology firms of Taiwan, we examined the impacts of social capital on creativity of R&D project teams from an intra‐team perspective. Results of factor analysis revealed four factors extracted from the concept of social capital, namely social interaction, network ties, mutual trust, and shared goals. Findings suggested that social interaction and network ties had significant and positive impacts on creativity of R&D project teams, but mutual trust and shared goals did not. Managerial implications for managing social capital in R&D project teams are discussed.
A temperature and current velocity mooring, located on the upper continental slope of the northern South China Sea, recorded a number of second baroclinic mode (mode 2) internal solitary waves ...(ISWs). These types of waves are seldom observed in nature. The mode 2 ISWs typically showed upward (downward) displacement of isotherms in the upper (lower) water column and three layers of eastward, westward, and eastward current from the uppermost to bottommost portions of a wave. In summer, westward‐propagating mode 2 ISWs were observed only occasionally. These waves generally appeared after mode 1 ISWs, a feature that may relate to the diurnal tide with a period of approximately 24 hours. The displacement of isotherms induced by mode 2 ISWs was 20 ± 14 m at 75 m and −22 ± 15 m at 240 m, and the characteristic time scale was approximately 8.0 ± 4.3 min. In winter, mode 2 ISWs were more active but mode 1 ISWs were rarely observed. Isotherm displacement by mode 2 ISWs in winter was 30 ± 18 m at 75 m and −26 ± 16 m at 240 m, and the average characteristic time scale was 6.9 ± 4.6 min. The mode 2 ISWs thus had larger amplitudes and smaller time scales in winter than they did in summer. The observed vertical temperature profile also showed notable seasonal change. The thermocline was shallow in summer and deep in winter. In winter, vertical temperature profiles indicated that the main thermocline was located near middepth over the upper continental slope near the 350 m isobath. Mode 1 ISWs were more active in summer than in winter, reflecting the larger Ursell numbers for mode 1 ISWs in summer. Among mode 2 ISWs in summer, 90% appeared after mode 1 ISWs. These results suggest that mode 2 ISWs could be related to mode 1 ISWs. In contrast, mode 2 ISWs were more active in winter than in summer, with larger mode 2 Ursell numbers also found in winter. Among winter mode 2 ISWs, 72% appeared without mode 1 ISWs. Mode 2 ISWs in winter could be related to the main thermocline being located near middepth. These seasonal variations of mode 2 ISWs were correlated with the seasonal change of local stratification. Further study on the different generating mechanisms of mode 2 ISWs in summer and winter is needed.
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