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The geopotential height observations from the Aura Microwave Limb Sounder show that the quasi‐6‐day wave (Q6DW) events with westward zonal wavenumber 1 (W1) in the Northern Hemisphere (NH) mesosphere and lower thermosphere (MLT) during September 2013 and 2014 had a prolonged lifetime of ∼45–50 days and reached their maximum amplitudes after the September equinox, while the climatological Q6DW‐W1 is completely dissipated in the background atmosphere before the equinoxes. The Eliassen‐Palm flux diagnostic results indicate that Q6DW‐W1 during September 2013 and 2014 obtained an additional source at ∼60°‐80°S and ∼40–50 km as the September equinox approached, which is related to the baroclinic/barotropic instability in this region. Further investigation on the background atmosphere reveals that several stratospheric minor warming (SMW) events occurred in the Antarctic region during September 2013 and 2014 due to the enhancement of wavenumber 1 activities, accompanied by the increase in the stratospheric temperature, changes in the shape of the polar vortex and the reversal in the zonal mean circulation. The strong planetary wave breaking during the September 2013 and 2014 Antarctic SMW events significantly weakened the strength of the polar night jet (PNJ) and made its peak height descend below ∼35 km, which generated the baroclinic/barotropic instability at the new upper boundary of the PNJ (∼60°‐80°S and ∼40–50 km) by an anomalous double‐jet configuration in the background winds. This unusual instability provided additional wave source and energy for the trans‐equatorial propagation of Q6DW‐W1, which finally led to prolonged wave activities in the NH MLT region. Plain Language Summary: Previous studies have suggested that sudden stratosphere warming (SSW) during wintertime can additionally trigger large‐amplitude traveling planetary waves (PWs) in the mesosphere and lower thermosphere (MLT) region. However, due to the lower occurrence rate and intensity, there are few opportunities to study the impact of Southern Hemisphere (SH) stratospheric warming on global PW behaviors, especially for the climatological event of the eigenmode in the Earth's atmosphere. The Aura satellite observations show that the third climatological event of quasi‐6‐day wave (Q6DW) with westward zonal wavenumber 1 (W1) over one year had an exceptionally long duration in the Northern Hemisphere (NH) MLT region in 2013 and 2014, and abnormally peaked after the September equinox, which is not observed in other years since 2004. The reanalysis data confirms that the stratospheric minor warming (SMW) events occurred over the Antarctic region during September 2013 and 2014, which generated instability under an unusual double‐jet structure in the background winds to provide additional energy for the extension of Q6DW‐W1. The current results establish the relationship between the abnormal PW activities in the NH MLT region and the Antarctic SMW events and provide the first observational evidence that the double‐jet structure can influence the westward propagating PW. Key Points: The duration of the quasi‐6‐day wave (Q6DW) with s = 1 (W1) in the Northern Hemisphere (NH) was greatly extended in September 2013 and 2014The Antarctic stratospheric minor warmings provided additional wave sources to disrupt the typical dissipation pattern of Q6DW‐W1 in the NHThe impact of the double‐jet structure in the Southern Hemisphere on the behavior of westward propagating planetary waves is first observed [ABSTRACT FROM AUTHOR]

During February 2023, the quasi‐4‐day wave (Q4DW) with westward zonal wavenumber 2 (W2) reached its largest amplitude of ∼400 m in the Southern Hemisphere (SH) geopotential height observations since 2004, which occurred simultaneously with an Arctic major sudden stratospheric warming (SSW) with an elevated stratopause (ES). However, the Q4DW‐W2 perturbations in the Northern Hemisphere (NH) were unexpectedly suppressed despite the unstable Arctic stratosphere and mesosphere during the 2023 ES‐SSW. Diagnostic analysis shows that the westward winds at ∼54°N–70°N in the upper stratosphere of ∼‐79 m/s during the 2023 ES‐SSW were the strongest during boreal winters over the past two decades, which benefited from the onset of a preceding minor SSW at the end of January. The strongest westward wind generated a wave geometry configuration of full reflection for Q4DW‐W2 in the NH, while the Q4DW‐W2 enhancement in the SH was induced by the in‐situ amplification of the surviving seeding perturbations. Plain Language Summary: Among the planetary waves with a period of about 4 days, the eastward quasi‐4‐day wave (Q4DW) excited by the double‐jet structure in the Southern Hemisphere is the most famous one, while another Q4DW with westward zonal wavenumber 2 (W2) belonging to the normal modes of the Earth's atmosphere has attracted little attention. During the February 2023 sudden stratospheric warming (SSW) with an elevated stratopause (ES), the exceptional enhancement and suppression of Q4DW‐W2 were captured in the Southern Hemisphere and Northern Hemisphere, respectively. Such global structure is first observed and abnormal among traveling planetary waves during SSW since they usually have a peak region in the unstable winter hemisphere. We found that the rare sequence of stratospheric disturbances in the 44‐year historical record that a minor SSW followed by an ES‐SSW led to the excessively strong westward wind during the 2023 ES‐SSW, which resulted in a wave geometry configuration of full reflection for Q4DW‐W2 in the Northern Hemisphere. Our current results well establish the relationship between a new global structure of traveling planetary waves during SSW and the rare sequence of stratospheric disturbances. This will deepen the understanding of the less studied Q4DW‐W2 and the Earth's whole atmospheric coupling during SSW. Key Points: The anomalous burst and suppression of quasi‐4‐day wave (Q4DW) with westward zonal wavenumber 2 (W2) were observed in the Southern Hemisphere and Northern Hemisphere (NH) respectively during the February 2023 major sudden stratospheric warming (SSW) with elevated stratopause (ES)The rare sequence of SSWs in January and February 2023 led to the strongest westward wind during boreal winters over the past two decadesThe strongest westward wind during the 2023 ES‐SSW created a wave geometry configuration of full reflection weakening the Q4DW‐W2 in the NH [ABSTRACT FROM AUTHOR]

We studied the response of ionospheric total electron content (TEC) and equatorial electrojet (EEJ) to the ultra‐fast Kelvin wave (UFKW) at the equator in the mesosphere using zonal wind data obtained from TIMED Doppler Interferometer (TIDI), EEJ data over the monitoring station Jicamarca (12°S, 77°W) and global TEC maps. The least squares fitting method is utilized to perform a spectral analysis of zonal wind, EEJ and TEC. Our analysis results demonstrate that UFKW events can be divided into four categories: (a) UFKW events with both TEC and EEJ response; (b) UFKW events with TEC response but without EEJ response; (c) UFKW events with EEJ response but without TEC response; (d) UFKW events without neither TEC response nor EEJ response. The first type of UFKW events occur the most often and is generally thought to generate a response in EEJ at approximately 105–110 km through the dynamo effect. The polarization electric field associated with EEJ then produces a response in the ionospheric TEC through the fountain effect. The lack of EEJ response in the second type of UFKWs may be due to the influence of eastward background winds. We found that all UFKW events with EEJ response have a response in TEC. The fourth type of UFKWs have smaller amplitudes, shorter vertical wavelengths and longer periods, which make them more likely to dissipate and cannot propagate to higher altitudes. These UFKWs cannot propagate to the altitude of EEJ and produce a response in EEJ, much less in TEC. Plain Language Summary: Ultra‐fast Kelvin wave (UFKW) is a typical planetary wave with the periods of approximately 2–5 days in the equatorial region. UFKWs not only affect the dynamics of mesosphere and lower thermosphere, but also produce responses in the ionosphere. Thus, the entire physical mechanism of how UFKW propagates to the ionosphere and produces response is the focus of our study. In this paper, we study the response of UFKWs in the equatorial electrojet (EEJ) and total electron content (TEC) by using the zonal wind data obtained from TIMED Doppler Interferometer (TIDI), EEJ data over the monitoring station Jicamarca (12°S, 77°W) and global TEC maps. Our analysis result shows that there are four different UFKW events according to EEJ and TEC response. The UFKWs usually generate a response in EEJ and then propagate upward to TEC. However, some UFKWs may not respond in EEJ at 110 km due to eastward background winds. We also find that all UFKW events with EEJ response have a response in TEC. As for the UFKWs without neither EEJ nor TEC response, they have smaller amplitudes, shorter vertical wavelengths and longer periods, which make them more likely to dissipate and cannot propagate to higher altitudes. Key Points: All ultra‐fast Kelvin wave (UFKW) events that generate a response in equatorial electrojet (EEJ) also generate a response in total electron content (TEC)Some UFKWs may not generate a response in EEJ due to eastward background windsUFKW events with long period, small amplitude and short vertical wavelength are hard to produce responses in EEJ and TEC [ABSTRACT FROM AUTHOR]

Objectives: We aimed to assess the feasibility and efficacy of laparoscopic extravascular stent in treatment of nutcracker syndrome by transperitoneal or retroperitoneal approach. Methods: Seventy‐six patients with nutcracker syndrome were retrospectively enrolled from a tertiary referral center, and underwent transperitoneal (63 patients) or retroperitoneal (13 patients) laparoscopic extravascular stent from March 2011 to December 2020. Surgical parameters, complications, imaging and clinical outcomes were collected and analyzed. Results: All procedures were successfully carried out without open conversion. The median operation time, estimated blood loss, and postoperative hospital day were 120 (interquartile range [IQR]: 90–144) min, 20 (IQR: 10–30) ml, and 7 (IQR: 6–9) days. At a median follow‐up of 52 (range: 9–127) months, 60 (79%) patients had complete symptom resolution, 14 (18%) patients had significant symptom improvement, and 2 (3%) patients reported no symptom improvement. Ninety‐four percent (50/53) of hematuria, 91% (30/33) of proteinuria, and 89% (25/28) of flank/abdominal pain resolved after extravascular LRV stenting. No significant differences were detected in surgery parameters and recovery rates of clinical symptoms between two approaches (each p > 0.05). However, patients with transperitoneal approach need longer to achieve complete recovery compared with retroperitoneal approach (8.7 vs. 1.5 months, p = 0.016). Conclusions: Laparoscopic extravascular stent performed either transperitoneally or retroperitoneally is a feasible and effective option in treatment of nutcracker syndrome. Retroperitoneal laparoscopic extravascular stent required shorter time to achieve complete recovery, which should be considered whenever possible in surgical decision‐making. [ABSTRACT FROM AUTHOR]

GreenTotal Factor Productivity (GTFP) is a critical indicator for measuring the green development and transformation of the economy, with profound implications for achieving energy conservation and developing the economy. In the context of the digital economy, digital entrepreneurship, as one of the important channels for digital industrialization, will have an effect on the promotion of GTFP. This study combines panel data from 219 Chinese cities at the prefectural level and above from 2007 to 2020 to examine the effect of digital entrepreneurship activities on GTFP. The empirical results show that digital entrepreneurial activity significantly reduces both GTFP and energy efficiency. Meanwhile, the effect of digital entrepreneurship activity on GTFP through industrial structure upgrading is not significant. Furthermore, a substantial negative correlation is identified between GTFP and digital entrepreneurship activity in the digital manufacturing industry, and in the eastern and central region. [ABSTRACT FROM AUTHOR]

Based on the need to protect previous ancient trees and the development of dendroclimatology, the use of non-destructive technologies in tree-ring research has gained increasing attention. This study focuses on the ancient Pinus tabulaeformis in Yu Xiang Forest Farm in Henan Province. Firstly, samples were collected using the traditional Increment borers and the Resistograph, a non-destructive method. Subsequently, the peak-valley analysis was used to filter the data obtained by the Resistograph to extract the tree ring width sequence, and the data's accuracy was verified by correlation analysis with tree ring width sequence by the Increment borers. Then, the optimal filtering method and an appropriate comprehensive threshold were determined, and tree ring width and density sequences were successfully extracted. Following that, the growth trend and residual resistance in the measurement process were corrected using linear fitting and Ensemble Empirical Mode Decomposition (EEMD) technology, thereby establishing the tree-ring width and density index series, which were further validated through correlation analysis and t-tests. Finally, analysis of the correlation with climatic factors, identified the main limiting factors for tree growth, and the accuracy of the tree-ring information extracted by the Resistograph was further verified. The results showed that spite of certain differences between the tree-ring width indices extracted by the Resistograph and the Increment borer, they were generally reliable. The radial growth of the ancient P.tabulaeformis in Yu Xiang Forest Farm is primarily influenced by temperature, with the maximum density of the tree rings responding more significantly to the mean maximum temperature, while the minimum density of the tree rings responded more significantly to the mean minimum temperature. These results not only provide a scientific and accurate age for the protection of ancient trees and verify the reliability of the data obtained by the Resistograph, but also facilitate the use of non-destructive technology for in-depth study of ancient trees, therefore enhancing our understanding of how climate change affects tree growth and provide valuable insights for the future protection and management of these ancient trees., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Li, Liu, Wei, Li, Zhang, Wei and Peng.)