Atmospheric escape plays a critical role in shaping the long-term climate evolution of Mars.Among the various escape mechanisms,energetic neutral atoms(ENAs)generated through charge exchange between solar wind ions an...Atmospheric escape plays a critical role in shaping the long-term climate evolution of Mars.Among the various escape mechanisms,energetic neutral atoms(ENAs)generated through charge exchange between solar wind ions and exospheric neutrals serve as an important diagnostic for ion-neutral interactions and upper atmospheric loss.This study presents direct observations of hydrogen ENAs(H-ENAs)on the dayside of Mars by using the Mars Ion and Neutral Particle Analyzer(MINPA)onboard China’s Tianwen-1 orbiter.By analyzing H-ENA data during a coronal mass ejection and a stream interaction region from December 29,2021,to January 1,2022,and comparing these data with MAVEN/SWIA(Mars Atmosphere and Volatile EvolutioN/Solar Wind Ion Analyzer)solar wind measurements,we examine the temporal evolution of H-ENA flux and the associated sputtered escape of atmospheric constituents.The observed H-ENA velocity is consistent with upstream solar wind ions,and the H-ENA-to-ion intensity ratio is used to infer variations in exospheric density,revealing a delayed response to enhanced solar wind activity.Penetrating H-ENA intensities reach up to 5.3×10^(6)s^(−1) cm^(−2),with energy fluxes on the order of(0.5-8.1)×10^(−3) mW/m^(2).The estimated oxygen sputtered escape rate driven by penetrating H-ENAs ranges from 5.5×10^(23)s^(−1) to 5.2×10^(24)s^(−1),comparable to or exceeding previous estimates based on penetrating ions.The findings highlight the need for low-altitude H-ENA observations to better quantify their atmospheric interactions and refine our understanding of nonthermal escape processes at Mars.展开更多
INTRODUCTIONThe mechanism that DNA hypomethylation leads toactivation of oncogene and occurrence of malignantneoplasm is being increasingly recognized byresearchers. Normal DNA methylation playsimportant role in stabi...INTRODUCTIONThe mechanism that DNA hypomethylation leads toactivation of oncogene and occurrence of malignantneoplasm is being increasingly recognized byresearchers. Normal DNA methylation playsimportant role in stabilizing the phenotype of cell.DNA methylation status reduction and/or patternalteration are related to activation and abnormallyhigh expression of some oncogenes and cellularmalignancy[1-6]. c-fms oncogene encodes for colonystimulating factor 1 receptor (CSF-1R)[7], c-fms/CSF-1R was highly expressed in hepatocellularcarcinoma (HCC) tissue, but the mechanismremained obscure[8,9].展开更多
INTRODUCTIONInsulin-like growth factor Ⅱ(IGF-Ⅱ) is a mitogenic peptide of 74 kD and is mostly synthesized in fetal liver tissue .IGF-Ⅱ is believed to play an important role in fetal growth and development and is in...INTRODUCTIONInsulin-like growth factor Ⅱ(IGF-Ⅱ) is a mitogenic peptide of 74 kD and is mostly synthesized in fetal liver tissue .IGF-Ⅱ is believed to play an important role in fetal growth and development and is involved in cellular proliferation and differentiation[1-5]. Recently ,several researchers have reported increased expression of the IGF-Ⅱgene in human hepatocellular carcinoma (HCC) and adjacent non-cancerous liver tissues [6-10].展开更多
AIM:To explore endoscopic therapy methods for gastric stromal tumors originating from the muscularis propria.METHODS:For 69 cases diagnosed as gastric stromal tumors originating from the muscularis propria,three types...AIM:To explore endoscopic therapy methods for gastric stromal tumors originating from the muscularis propria.METHODS:For 69 cases diagnosed as gastric stromal tumors originating from the muscularis propria,three types of endoscopic therapy were selected,based on the size of the tumor.These methods included endoscopic ligation and resection(ELR),endoscopic submucosal excavation(ESE) and endoscopic full-thickness resection(EFR).The wound surface and the perforation of the gastric wall were closed with metal clips.Immunohistostaining for CD34,CD117,Dog-1,S-100 and smooth muscle actin(SMA) was performed on the resected tumors.RESULTS:A total of 38 cases in which the tumor size was less than 1.2 cm were treated with ELR;three cases were complicated by perforation,and the perforations were closed with metal clips.Additionally,18 cases in which the tumor size was more than 1.5 cm were treated with ESE,and no perforation occurred.Finally,13 cases in which the tumor size was more than 2.0 cm were treated with EFR;all of the cases were complicated by artificial perforation,and all of the perforations were closed with metal clips.All of the 69 cases recovered with medical treatment,and none required surgical operation.Immunohistostaining demonstrated that among all of the 69 gastric stromal tumors diagnosed by gastroscopy,12 cases were gastric leiomyomas(SMA-positive),and the other 57 cases were gastric stromal tumors.CONCLUSION:Gastric stromal tumors originating from the muscularis propria can be treated successfully with endoscopic techniques,which could replace certain surgical operations and should be considered for further application.展开更多
AIM: To evaluate the efficacy, safety and feasibility of endoscopic full-thickness resection (EFR) for the treatment of gastric submucosal tumors (SMTs) arising from the muscularis propria.
Objective: To observe cyclooxygenase (COX)-2 expression in normal oral mucosa (NOM), oral lichen planus (OLP) and oral squamous cell carcinoma (OSCC) and explore its significance in the incidence of oral cancer. Metho...Objective: To observe cyclooxygenase (COX)-2 expression in normal oral mucosa (NOM), oral lichen planus (OLP) and oral squamous cell carcinoma (OSCC) and explore its significance in the incidence of oral cancer. Methods: The immunohistochemical method and RT-PCR method were applied to detect the expression of COX-2 and MMP-7 in 10 cases with NOM, 33 cases of with OLP and 38 cases with OSCC. Results: The expression of COX-2 mRNA in OSCC tissues (68.4%, 26/38) was significantly higher than in the OLP (24.2%, 8/33) and NOM (0.0%, 0/10) ( P<0.01). The expression of MMP-7 mRNA in OSCC tissues (65.8%, 25/38) was significantly higher than in the OLP (30.3%, 10/33) and NOM (0.0%, 0/10) ( P<0.01). The expression of MMP-7 in OLP was significantly higher than in the NOM ( P<0.05). There was no significant expression of COX-2 protein in NOM, and the positive rate was 42.4% (14/33) and 89.5% (34/38) in OLP and OSCC group, respectively. The COX-2 expression in cancer tissues was significantly higher than in NOM and OLP ( P<0.05). The MMP-7 protein expression in cancer tissues (84.2%, 32/38) was significantly higher than in NOM (10.0%, 1/10) and in OLP (42.4%, 14/33), and the positive rate in OLP was significantly higher than in NOM ( P<0.01). The COX-2 expression was associated with clinical stage ( P<0.05), the MMP-7 expression was associated with clinical stage and lymph node metastasis ( P<0.05). The expressions of COX-2 and MMP-7 mRNA were positively correlated with OSCC. Conclusions: The abnormal expressions of COX-2 and MMP-7 are closely related to the biological behavior of OSCC, the MMP-7 may be induced by COX-2, and further lead to the invasion and metastasis of OSCC.展开更多
AIM: To assess the effectiveness of endoscopic full-thickness resection (EFR) and laparoscopic surgery in the treatment of gastric stromal tumors arising from the muscularis propria.
Our previous studies indicated that tomato miR482b could negatively regulate the resistance of tomato to Phytophthora infestans and the expression of miR482b was decreased after inoculation with P.infestans.However,th...Our previous studies indicated that tomato miR482b could negatively regulate the resistance of tomato to Phytophthora infestans and the expression of miR482b was decreased after inoculation with P.infestans.However,the mechanism by which the accumulation of miR482b is suppressed remains unclear.In this study,we wrote a program to identify 89 long noncoding RNA(lncRNA)-originated endogenous target mimics(eTMs)for 46 miRNAs from our RNA-Seq data.Three tomato lncRNAs,lncRNA23468,lncRNA01308 and lncRNA13262,contained conserved eTM sites for miR482b.When lncRNA23468 was overexpressed in tomato,miR482b expression was significantly decreased,and the expression of the target genes,NBS-LRRs,was significantly increased,resulting in enhanced resistance to P.infestans.Silencing lncRNA23468 in tomato led to the increased accumulation of miR482b and decreased accumulation of NBS-LRRs,as well as reduced resistance to P.infestans.In addition,the accumulation of both miR482b and NBS-LRRs was not significantly changed in tomato plants that overexpressed lncRNA23468 with a mutated eTM site.Based on the VIGS system,a target gene of miR482b,Solyc02g036270.2,was silenced.The disease symptoms of the VIGS-Solyc02g036270.2 tomato plants were in accordance with those of tomato plants in which lncRNA23468 was silenced after inoculation with P.infestans.More severe disease symptoms were found in the modified plants than in the control plants.Our results demonstrate that lncRNAs functioning as eTMs may modulate the effects of miRNAs in tomato and provide insight into how the lncRNA23468-miR482b-NBS-LRR module regulates tomato resistance to P.infestans.展开更多
Tomato is an important horticultural and economic crop cultivated worldwide.As Phytophthora infestans becomes a huge threat to tomato production,it is necessary to study the resistance mechanisms of tomato against P.i...Tomato is an important horticultural and economic crop cultivated worldwide.As Phytophthora infestans becomes a huge threat to tomato production,it is necessary to study the resistance mechanisms of tomato against P.infestans.Our previous research has found that miR482 might be involved in tomato–P.infestans interaction.In this study,miR482b precursor was cloned from Solanum pimpinellifolium“L3708”and miR482b was shown to decrease in abundance in tomato following P.infestans infection.Compared to wild-type tomato plants,tomato plants that overexpressed miR482b displayed more serious disease symptoms after P.infestans infection,with more necrotic cells,longer lesion diameters,and increased P.infestans abundance.Meanwhile,silencing of miR482b was performed by short tandem target mimic(STTM),resulting in enhancement of tomato resistance to P.infestans.Using miRNA and degradome data sets,NBS–LRR disease-resistance genes targeted by miR482b were validated.Negative correlation between the expression of miR482b and its target genes was found in all miR482b-overexpressing and-silencing tomato plants.Our results provide insight into tomato miR482b involved in the response to P.infestans infection,and demonstrate that miR482b–NBS–LRR is an important component in the network of tomato–P.infestans interaction.展开更多
BACKGROUND There are many types of treatments for calcaneal fractures,including conservative treatment,conventional surgical treatment,and minimally invasive surgery.The choice of specific treatment options is still c...BACKGROUND There are many types of treatments for calcaneal fractures,including conservative treatment,conventional surgical treatment,and minimally invasive surgery.The choice of specific treatment options is still controversial.Open reduction and internal fixation are currently the most commonly used surgical procedures in the clinic.A good fracture reduction effect can be achieved by using the lateral extension incision of the calcaneus;however,many studies have reported a high incidence of postoperative incision complications.Although there are many methods for the classification of intra-articular calcaneal fractures,it is generally believed that the computed tomography(CT)classification proposed by Sanders has high application value in the selection of treatment methods and evaluation of prognosis of calcaneal fractures.However,this method has no clear guiding significance for the choice of surgical incision and surgical plan.AIM To explore the application and clinical efficacy of medial column classification in the treatment of intra-articular calcaneal fractures.METHODS From July 2017 to July 2018,91 patients,including 60 males and 31 females aged 27 to 60 years,were enrolled.All participants had closed intra-articular calcaneal fracture,and their surgical options were selected under the guidance of medial column classification.The patients'fractures were classified according to the Sanders classification:Type II,35 cases;Type III,33 cases;and Type IV,23 cases.Among them,53 patients had medial column displacement(shortened varus)and underwent open reduction and internal fixation with L-lateral incision of the calcaneus;38 patients had no displacement of the medial column and underwent open reduction and internal fixation with tarsal sinus incision.The calcaneus Bohler angle,Gissane angle,length,width,height,and step thickness of the articular surface were evaluated by X-ray and three-dimensional CT before and after surgery and at the last follow-up.Foot function recovery was assessed by the Maryland foot scoring criteria.RESULTS All patients were followed for 5 to 14 mo,with an average of 10.5±2.9 mo.The fractures of all patients healed,and the healing time was 10 to 19 wk,with an average of 10.8±1.5 wk.One patient developed wound infection 1 wk after surgery and was actively debrided and implanted with antibiotic calcium sulfate to control the infection.The patient's fracture healed 5 mo after surgery.One patient developed a sural nerve injury,and the symptoms disappeared 3 mo after surgery.The patients were assessed according to the Maryland foot scoring system:Excellent in 77 cases,good in 10,and fair in 4.The excellent and good rate was 95.6%.CONCLUSION Medial column classification can effectively guide the surgical selection for intraarticular fractures of the calcaneus.展开更多
The small intestine is approximately 5-6 m long and occupies a large area in the abdominal cavity. These factors preclude the use of ordinary endoscopy and X-ray to thoroughly examine the small intestine for bleeding ...The small intestine is approximately 5-6 m long and occupies a large area in the abdominal cavity. These factors preclude the use of ordinary endoscopy and X-ray to thoroughly examine the small intestine for bleeding of vascular malformations. Thus,the diagnosis of intestinal bleeding is very difficult. A 47-year-old man presented at the hospital 5 mo ago with dark stool. Several angiomas were detected by oral approach enteroscopy,but no active bleeding was observed. Additionally,no lesions were detected by anal approach enteroscopy;however,gastrointestinal tract bleeding still occurred for an unknown reason. We performed an abdominal vascular enhanced computed tomography examination and detected ileal vascular malformations. Ileum angioma and vascular malformation were detected by a laparoscopic approach,and segmental resection was performed for both lesions,which were confirmed by pathological diagnosis. This report systemically emphasizes the imaging findings of small intestinal vascular malformation bleeding.展开更多
The Chang’E-4 mission has been exploring the lunar farside.Two scientific targets of the rover onboard are(1)resolving the possible mineralogy related to the South Pole-Aitken basin and(2)understanding the subsurface...The Chang’E-4 mission has been exploring the lunar farside.Two scientific targets of the rover onboard are(1)resolving the possible mineralogy related to the South Pole-Aitken basin and(2)understanding the subsurface processes at the lunar farside.Publications to date that are based on the reflectance spectra and radar data obtained by the rover have shown a persistent inconsistency about the local stratigraphy.To explain both the abnormal surface topography at the landing site and the unexpected radargram observed by the rover,the Alder crater has been frequently reported to be older than the mare basalts at that landing site.However,this argument is not supported by earlier geological mapping nor recent crater statistics.Resolving this controversy is critical for a full understanding of the geological history of the landing area and for correct interpretations of the scientific data returned.Employing detailed crater statistics,rigorous statistical analyses,and an updated crater chronology function,this study is determined to resolve the relative ages of the Alder crater,Finsen crater,and the mare basalts on the floor of Von Kármán.Our results reveal that while background secondaries and local resurfacing have widely occurred in the study area,affecting age determinations,the statistics are significant enough to conclude that the Alder crater is the oldest among the three targets.This independent constraint is consistent with both the crosscutting relationships of different terrains in this area and global stratigraphic mapping.Our results exclude Alder as a possible contributor of the post-mare deposits at the landing site,appealing for a more systematic stratigraphy study to resolve the provenances of these deposits.展开更多
The Martian ionosphere is produced by a number of controlling processes, including solar extreme ultraviolet radiation (EUV) and X-ray ionization, impact ionization by precipitating electrons, and day-to-night transpo...The Martian ionosphere is produced by a number of controlling processes, including solar extreme ultraviolet radiation (EUV) and X-ray ionization, impact ionization by precipitating electrons, and day-to-night transport. This study investigates the structural variability of the Martian ionosphere with the aid of the radio occultation (RO) experiments made on board the recent Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft. On the dayside, the RO electron density profiles are described by the superposition of two Chapman models, representing the contributions from both the primary layer and the low-altitude secondary layer. The inferred subsolar peak electron densities and altitudes are 1.24×10^5 cm^-3 and 127 km for the former, and 4.28×10^4 cm^-3 and 97 km for the latter, respectively, in general agreement with previous results appropriate for the low solar activity conditions. Our results strengthen the role of solar EUV and X-ray ionization as the driving source of plasma on the dayside of Mars. Beyond the terminator, a systematic decline in ionospheric total electron content is revealed by the MAVEN RO measurements made from the terminator crossing up to a solar zenith angle of 120°. Such a trend is indicative of day-to-night plasma transport as an important source for the nightside Martian ionosphere.展开更多
Citrate (Ct) was chosen as a typical chelator used in the Fe^(2+)-peroxydisulfate (PDS) process to improve sludge dewaterability.The PDS-Fe^(2+)-Ct process exhibited better performance in sludge dewatering than PDS-Fe...Citrate (Ct) was chosen as a typical chelator used in the Fe^(2+)-peroxydisulfate (PDS) process to improve sludge dewaterability.The PDS-Fe^(2+)-Ct process exhibited better performance in sludge dewatering than PDS-Fe^(2+).Specifically,with a PDS dosage of 1.2 mmol/g VS,the molar ratio of PDS/Fe^(2+)and Ct/Fe^(2+)were 4:5 and 1:4,respectively,the capillary suction time decreased from 155.8 to 24.8sec,and the sludge cake water content decreased from 82.62%to 64.11%(-0.06MPa).The oxidation led to a reduced negative charge and a decrease in particle size.The enhanced sludge dewaterability and changes of sludge properties were attributed to the decomposition of extracellular polymeric substances,and it was explored by protein,polysaccharide,3D-EEMs,and FT-IR.Additionally,the quenching experiments of radical species demonstrated that SO_(4)-·played a more important role than·OH,and its productivity was improved with the addition of Ct.Moreover,the reasons for the improved productivity of radicals with the addition of Ct were discussed.The results of this study could serve as a basis for improving sludge dewatering using the PDS-Fe^(2+)-Ct process and suggest that the addition of Ct may improve the productivity of SO_(4)-·in the activation o PDS via Fe^(2+).展开更多
We develop a model for calculating the radiation force on spherically symmetric multilayered particles based on the acoustic scattering approach.An expression is derived for the radiation force on a multilayered spher...We develop a model for calculating the radiation force on spherically symmetric multilayered particles based on the acoustic scattering approach.An expression is derived for the radiation force on a multilayered sphere centered on the axis of a Gaussian standing wave propagating in an ideal fluid,The effects of the sound absorption of the materials and sound wave on acoustic radiation force of a multilayered sphere immersed in water are analyzed,with particular emphasis on the shell thickness of every layer,and the width of the Gaussian beam.The results reveal that the existence of particle trapping behavior depends on the choice of the non-dimensional frequency ka,as well as the shell thickness of each layer.This study provides a theoretical basis for the development of acoustical tweezers in a Gaussian standing wave,which may benefit the improvement and development of acoustic control technology,such as trapping,sorting,and assembling a cell,and drug delivery applications.展开更多
BACKGROUND Lisfranc injuries have not received much attention by orthopedic doctors in the past,and there is little related research on the diagnosis and treatment of these injuries.In recent years with the rise in fo...BACKGROUND Lisfranc injuries have not received much attention by orthopedic doctors in the past,and there is little related research on the diagnosis and treatment of these injuries.In recent years with the rise in foot and ankle surgery,doctors are now paying more attention to this type of injury.However,there is still a high rate of missed diagnosis due to insufficient attention causing treatment delays or inadequate treatments,which eventually result in greater sequelae;including long-term pain,arthritis,foot deformity etc.In particular,for cases with a mild Lisfranc joint complex injury,the incidence of sequelae is higher.AIM To select an active surgical treatment for an atypical Lisfranc joint complex injury and to evaluate the clinical efficacy of the surgical treatment.METHODS The clinical data of 18 patients,including 10 males and 8 females aged 20-64 years with Lisfranc injuries treated in our department from January 2017 to September 2019 were retrospectively analyzed.All patients were treated with an open reduction and internal fixation method using locking titanium mini-plates and hollow screws or Kirschner wires.X-ray images were taken and follow-up was performed monthly after the operation;the internal fixation was then removed 4-5 mo after the operation;and the American Orthopedic Foot and Ankle Society(AOFAS)score was used for evaluation on the last follow-up.RESULTS All patients were followed up for 6-12 mo.A good/excellent AOFAS score was observed in 88.9%of patients.CONCLUSION For atypical Lisfranc joint complex injuries,active open reduction and internal fixation can be performed to enable patients to obtain a good prognosis and satisfactory functional recovery.展开更多
An important population of the dayside Martian ionosphere are photoelectrons that are produced by solar Extreme Ultraviolet and X-ray ionization of atmospheric neutrals.A typical photoelectron energy spectrum is chara...An important population of the dayside Martian ionosphere are photoelectrons that are produced by solar Extreme Ultraviolet and X-ray ionization of atmospheric neutrals.A typical photoelectron energy spectrum is characterized by a distinctive peak near 27 eV related to the strong solar HeⅡ emission line at 30.4 nm,and an additional peak near 500 eV related to O Auger ionization.In this study,the extensive measurements made by the Solar Wind Electron Analyzer on board the recent Mars Atmosphere and Volatile Evolution spacecraft are analyzed and found to verify the scenario that Martian ionosphere photoelectrons are driven by solar radiation.We report that the photoelectron intensities at the centers of both peaks increase steadily with increasing solar ionizing flux below 90 nm and that the observed solar cycle variation is substantially more prominent near the O Auger peak than near the HeⅡ peak.The latter observation is clearly driven by a larger variability in solar irradiance at shorter wavelengths.When the solar ionizing flux increases from 1 mW·m^-2 to 2.5 mW·m^-2,the photoelectron intensity increases by a factor of 3.2 at the HeⅡ peak and by a much larger factor of 10.5 at the O Auger peak,both within the optically thin regions of the Martian atmosphere.展开更多
In recent studies of the Martian atmosphere,strong diurnal variation in the dust was discovered in the southern hemisphere during major dust storms,which provides strong evidence that the commonly recognized meridiona...In recent studies of the Martian atmosphere,strong diurnal variation in the dust was discovered in the southern hemisphere during major dust storms,which provides strong evidence that the commonly recognized meridional transport process is driven by thermal tides.This process,when coupled with deep convection,could be an important part of the short-term atmospheric dynamics of water escape.However,the potential of this process to alter the horizontal distribution of moist air has not been systematically investigated.In this work,we conducted pre-research on the horizontal transport of water vapor associated with the migrating diurnal tide(DW1)at 50 Pa in the upper troposphere during major dust storms based on the Mars Climate Database(MCD)5.3,a state-of-the-art database for Martian atmospheric research that has been validated as simulating the relevant short-period atmospheric dynamics well.We found westward-propagating diurnal patterns in the global water vapor front during nearly all the major dust storms from Martian years(MYs)24 to 32.Statistical and correlation analyses showed that the diurnal transport of water vapor during global and A-season regional dust storms is dominated by the DW1.The effect of the tidal transport of water vapor varies with the types of dust storms in different seasons.During regional dust storms,the tidal transport induces only limited diurnal motion of the water vapor.However,the horizontal tidal wind tends to increase the abundance of daytime water vapor at mid-to low latitudes during the MY 28 southern summer global dust storm while decreasing it during the MY 25 southern spring global dust storm.The tidal transport process during these two global dust storms can induce opposite effects on water escape.展开更多
Electron pitch angle distributions similar to bidirectional electron conics(BECs)have been reported at Mars in previous studies based on analyses of Mars Global Surveyor measurements.BEC distribution,also termed“butt...Electron pitch angle distributions similar to bidirectional electron conics(BECs)have been reported at Mars in previous studies based on analyses of Mars Global Surveyor measurements.BEC distribution,also termed“butterfly”distribution,presents a local minimum flux at 90°and a maximum flux before reaching the local loss cone.Previous studies have focused on 115 eV electrons that were produced mainly via solar wind electron impact ionization.Here using Solar Wind Electron Analyzer measurements made onboard the Mars Atmosphere and Volatile Evolution spacecraft,we identify 513 BEC events for 19-55 eV photoelectrons that were generated via photoionization only.Therefore,we are investigating electrons observed in regions well away from their source regions,to be distinguished from 115 eV electrons observed and produced in the same regions.We investigate the spatial distribution of the 19-55 eV BECs,revealing that they are more likely observed on the nightside as well as near strong crustal magnetic anomalies.We propose that the 19-55 eV photoelectron BECs are formed due to day-to-night transport and the magnetic mirror effect of photoelectrons moving along cross-terminator closed magnetic field lines.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 42188101, 42274211, 41974170, 42374184, 42122032, and 41974196)the Chinese Academy of Sciences (Grant Nos. QYZDJSSW-JSC028, XDA15052500, XDA17010301, and XDB41000000)+3 种基金the CNSA (Grant No. D050103)the Specialized Research Fund for State Key Laboratories of Chinathe Specialized Research Fund for Laboratory of Geospace Environment of the University of Science and Technology of Chinasupported by the International Space Science Institute (ISSI) in Bern and Beijing through the ISSI/ISSI-BJ International Team Project titled “Understanding the Mars Space Environment Through Multi-Spacecraft Measurements” (ISSI Team Project No. 23-582 and ISSI-BJ Team Project No. 58)
文摘Atmospheric escape plays a critical role in shaping the long-term climate evolution of Mars.Among the various escape mechanisms,energetic neutral atoms(ENAs)generated through charge exchange between solar wind ions and exospheric neutrals serve as an important diagnostic for ion-neutral interactions and upper atmospheric loss.This study presents direct observations of hydrogen ENAs(H-ENAs)on the dayside of Mars by using the Mars Ion and Neutral Particle Analyzer(MINPA)onboard China’s Tianwen-1 orbiter.By analyzing H-ENA data during a coronal mass ejection and a stream interaction region from December 29,2021,to January 1,2022,and comparing these data with MAVEN/SWIA(Mars Atmosphere and Volatile EvolutioN/Solar Wind Ion Analyzer)solar wind measurements,we examine the temporal evolution of H-ENA flux and the associated sputtered escape of atmospheric constituents.The observed H-ENA velocity is consistent with upstream solar wind ions,and the H-ENA-to-ion intensity ratio is used to infer variations in exospheric density,revealing a delayed response to enhanced solar wind activity.Penetrating H-ENA intensities reach up to 5.3×10^(6)s^(−1) cm^(−2),with energy fluxes on the order of(0.5-8.1)×10^(−3) mW/m^(2).The estimated oxygen sputtered escape rate driven by penetrating H-ENAs ranges from 5.5×10^(23)s^(−1) to 5.2×10^(24)s^(−1),comparable to or exceeding previous estimates based on penetrating ions.The findings highlight the need for low-altitude H-ENA observations to better quantify their atmospheric interactions and refine our understanding of nonthermal escape processes at Mars.
基金Supported by the Natural Science Foundation of Guangdong Province, No 990422
文摘INTRODUCTIONThe mechanism that DNA hypomethylation leads toactivation of oncogene and occurrence of malignantneoplasm is being increasingly recognized byresearchers. Normal DNA methylation playsimportant role in stabilizing the phenotype of cell.DNA methylation status reduction and/or patternalteration are related to activation and abnormallyhigh expression of some oncogenes and cellularmalignancy[1-6]. c-fms oncogene encodes for colonystimulating factor 1 receptor (CSF-1R)[7], c-fms/CSF-1R was highly expressed in hepatocellularcarcinoma (HCC) tissue, but the mechanismremained obscure[8,9].
基金Project supported by the National Nature Science Foundation of China,No.39470774
文摘INTRODUCTIONInsulin-like growth factor Ⅱ(IGF-Ⅱ) is a mitogenic peptide of 74 kD and is mostly synthesized in fetal liver tissue .IGF-Ⅱ is believed to play an important role in fetal growth and development and is involved in cellular proliferation and differentiation[1-5]. Recently ,several researchers have reported increased expression of the IGF-Ⅱgene in human hepatocellular carcinoma (HCC) and adjacent non-cancerous liver tissues [6-10].
文摘AIM:To explore endoscopic therapy methods for gastric stromal tumors originating from the muscularis propria.METHODS:For 69 cases diagnosed as gastric stromal tumors originating from the muscularis propria,three types of endoscopic therapy were selected,based on the size of the tumor.These methods included endoscopic ligation and resection(ELR),endoscopic submucosal excavation(ESE) and endoscopic full-thickness resection(EFR).The wound surface and the perforation of the gastric wall were closed with metal clips.Immunohistostaining for CD34,CD117,Dog-1,S-100 and smooth muscle actin(SMA) was performed on the resected tumors.RESULTS:A total of 38 cases in which the tumor size was less than 1.2 cm were treated with ELR;three cases were complicated by perforation,and the perforations were closed with metal clips.Additionally,18 cases in which the tumor size was more than 1.5 cm were treated with ESE,and no perforation occurred.Finally,13 cases in which the tumor size was more than 2.0 cm were treated with EFR;all of the cases were complicated by artificial perforation,and all of the perforations were closed with metal clips.All of the 69 cases recovered with medical treatment,and none required surgical operation.Immunohistostaining demonstrated that among all of the 69 gastric stromal tumors diagnosed by gastroscopy,12 cases were gastric leiomyomas(SMA-positive),and the other 57 cases were gastric stromal tumors.CONCLUSION:Gastric stromal tumors originating from the muscularis propria can be treated successfully with endoscopic techniques,which could replace certain surgical operations and should be considered for further application.
基金Supported by Natural Science Foundation of Shandong Province,No.ZR2013HM004
文摘AIM: To evaluate the efficacy, safety and feasibility of endoscopic full-thickness resection (EFR) for the treatment of gastric submucosal tumors (SMTs) arising from the muscularis propria.
基金supported by Jinan Science and Technology Development Plans Grant (No.201121040)
文摘Objective: To observe cyclooxygenase (COX)-2 expression in normal oral mucosa (NOM), oral lichen planus (OLP) and oral squamous cell carcinoma (OSCC) and explore its significance in the incidence of oral cancer. Methods: The immunohistochemical method and RT-PCR method were applied to detect the expression of COX-2 and MMP-7 in 10 cases with NOM, 33 cases of with OLP and 38 cases with OSCC. Results: The expression of COX-2 mRNA in OSCC tissues (68.4%, 26/38) was significantly higher than in the OLP (24.2%, 8/33) and NOM (0.0%, 0/10) ( P<0.01). The expression of MMP-7 mRNA in OSCC tissues (65.8%, 25/38) was significantly higher than in the OLP (30.3%, 10/33) and NOM (0.0%, 0/10) ( P<0.01). The expression of MMP-7 in OLP was significantly higher than in the NOM ( P<0.05). There was no significant expression of COX-2 protein in NOM, and the positive rate was 42.4% (14/33) and 89.5% (34/38) in OLP and OSCC group, respectively. The COX-2 expression in cancer tissues was significantly higher than in NOM and OLP ( P<0.05). The MMP-7 protein expression in cancer tissues (84.2%, 32/38) was significantly higher than in NOM (10.0%, 1/10) and in OLP (42.4%, 14/33), and the positive rate in OLP was significantly higher than in NOM ( P<0.01). The COX-2 expression was associated with clinical stage ( P<0.05), the MMP-7 expression was associated with clinical stage and lymph node metastasis ( P<0.05). The expressions of COX-2 and MMP-7 mRNA were positively correlated with OSCC. Conclusions: The abnormal expressions of COX-2 and MMP-7 are closely related to the biological behavior of OSCC, the MMP-7 may be induced by COX-2, and further lead to the invasion and metastasis of OSCC.
基金Supported by Natural Science Foundation of Shandong Province,No.ZR2013HM004
文摘AIM: To assess the effectiveness of endoscopic full-thickness resection (EFR) and laparoscopic surgery in the treatment of gastric stromal tumors arising from the muscularis propria.
基金supported by grants from the National Natural Science Foundation of China(Nos.31471880 and 61472061).
文摘Our previous studies indicated that tomato miR482b could negatively regulate the resistance of tomato to Phytophthora infestans and the expression of miR482b was decreased after inoculation with P.infestans.However,the mechanism by which the accumulation of miR482b is suppressed remains unclear.In this study,we wrote a program to identify 89 long noncoding RNA(lncRNA)-originated endogenous target mimics(eTMs)for 46 miRNAs from our RNA-Seq data.Three tomato lncRNAs,lncRNA23468,lncRNA01308 and lncRNA13262,contained conserved eTM sites for miR482b.When lncRNA23468 was overexpressed in tomato,miR482b expression was significantly decreased,and the expression of the target genes,NBS-LRRs,was significantly increased,resulting in enhanced resistance to P.infestans.Silencing lncRNA23468 in tomato led to the increased accumulation of miR482b and decreased accumulation of NBS-LRRs,as well as reduced resistance to P.infestans.In addition,the accumulation of both miR482b and NBS-LRRs was not significantly changed in tomato plants that overexpressed lncRNA23468 with a mutated eTM site.Based on the VIGS system,a target gene of miR482b,Solyc02g036270.2,was silenced.The disease symptoms of the VIGS-Solyc02g036270.2 tomato plants were in accordance with those of tomato plants in which lncRNA23468 was silenced after inoculation with P.infestans.More severe disease symptoms were found in the modified plants than in the control plants.Our results demonstrate that lncRNAs functioning as eTMs may modulate the effects of miRNAs in tomato and provide insight into how the lncRNA23468-miR482b-NBS-LRR module regulates tomato resistance to P.infestans.
基金This work was supported by Grants from the NFSC(Nos.31471880 and 61472061).
文摘Tomato is an important horticultural and economic crop cultivated worldwide.As Phytophthora infestans becomes a huge threat to tomato production,it is necessary to study the resistance mechanisms of tomato against P.infestans.Our previous research has found that miR482 might be involved in tomato–P.infestans interaction.In this study,miR482b precursor was cloned from Solanum pimpinellifolium“L3708”and miR482b was shown to decrease in abundance in tomato following P.infestans infection.Compared to wild-type tomato plants,tomato plants that overexpressed miR482b displayed more serious disease symptoms after P.infestans infection,with more necrotic cells,longer lesion diameters,and increased P.infestans abundance.Meanwhile,silencing of miR482b was performed by short tandem target mimic(STTM),resulting in enhancement of tomato resistance to P.infestans.Using miRNA and degradome data sets,NBS–LRR disease-resistance genes targeted by miR482b were validated.Negative correlation between the expression of miR482b and its target genes was found in all miR482b-overexpressing and-silencing tomato plants.Our results provide insight into tomato miR482b involved in the response to P.infestans infection,and demonstrate that miR482b–NBS–LRR is an important component in the network of tomato–P.infestans interaction.
文摘BACKGROUND There are many types of treatments for calcaneal fractures,including conservative treatment,conventional surgical treatment,and minimally invasive surgery.The choice of specific treatment options is still controversial.Open reduction and internal fixation are currently the most commonly used surgical procedures in the clinic.A good fracture reduction effect can be achieved by using the lateral extension incision of the calcaneus;however,many studies have reported a high incidence of postoperative incision complications.Although there are many methods for the classification of intra-articular calcaneal fractures,it is generally believed that the computed tomography(CT)classification proposed by Sanders has high application value in the selection of treatment methods and evaluation of prognosis of calcaneal fractures.However,this method has no clear guiding significance for the choice of surgical incision and surgical plan.AIM To explore the application and clinical efficacy of medial column classification in the treatment of intra-articular calcaneal fractures.METHODS From July 2017 to July 2018,91 patients,including 60 males and 31 females aged 27 to 60 years,were enrolled.All participants had closed intra-articular calcaneal fracture,and their surgical options were selected under the guidance of medial column classification.The patients'fractures were classified according to the Sanders classification:Type II,35 cases;Type III,33 cases;and Type IV,23 cases.Among them,53 patients had medial column displacement(shortened varus)and underwent open reduction and internal fixation with L-lateral incision of the calcaneus;38 patients had no displacement of the medial column and underwent open reduction and internal fixation with tarsal sinus incision.The calcaneus Bohler angle,Gissane angle,length,width,height,and step thickness of the articular surface were evaluated by X-ray and three-dimensional CT before and after surgery and at the last follow-up.Foot function recovery was assessed by the Maryland foot scoring criteria.RESULTS All patients were followed for 5 to 14 mo,with an average of 10.5±2.9 mo.The fractures of all patients healed,and the healing time was 10 to 19 wk,with an average of 10.8±1.5 wk.One patient developed wound infection 1 wk after surgery and was actively debrided and implanted with antibiotic calcium sulfate to control the infection.The patient's fracture healed 5 mo after surgery.One patient developed a sural nerve injury,and the symptoms disappeared 3 mo after surgery.The patients were assessed according to the Maryland foot scoring system:Excellent in 77 cases,good in 10,and fair in 4.The excellent and good rate was 95.6%.CONCLUSION Medial column classification can effectively guide the surgical selection for intraarticular fractures of the calcaneus.
文摘The small intestine is approximately 5-6 m long and occupies a large area in the abdominal cavity. These factors preclude the use of ordinary endoscopy and X-ray to thoroughly examine the small intestine for bleeding of vascular malformations. Thus,the diagnosis of intestinal bleeding is very difficult. A 47-year-old man presented at the hospital 5 mo ago with dark stool. Several angiomas were detected by oral approach enteroscopy,but no active bleeding was observed. Additionally,no lesions were detected by anal approach enteroscopy;however,gastrointestinal tract bleeding still occurred for an unknown reason. We performed an abdominal vascular enhanced computed tomography examination and detected ileal vascular malformations. Ileum angioma and vascular malformation were detected by a laparoscopic approach,and segmental resection was performed for both lesions,which were confirmed by pathological diagnosis. This report systemically emphasizes the imaging findings of small intestinal vascular malformation bleeding.
基金the B-type Strategic Priority Program of the Chinese Academy of Sciences(Grant No.XDB41000000)the Science and Technology Development Fund of Macao(0042/2018/A2)+1 种基金the National Natural Science Foundation of China(No.41773063)the pre-research Project on Civil Aerospace Technologies(No.D020201 and D020202)that is funded by Chinese National Space Administration.
文摘The Chang’E-4 mission has been exploring the lunar farside.Two scientific targets of the rover onboard are(1)resolving the possible mineralogy related to the South Pole-Aitken basin and(2)understanding the subsurface processes at the lunar farside.Publications to date that are based on the reflectance spectra and radar data obtained by the rover have shown a persistent inconsistency about the local stratigraphy.To explain both the abnormal surface topography at the landing site and the unexpected radargram observed by the rover,the Alder crater has been frequently reported to be older than the mare basalts at that landing site.However,this argument is not supported by earlier geological mapping nor recent crater statistics.Resolving this controversy is critical for a full understanding of the geological history of the landing area and for correct interpretations of the scientific data returned.Employing detailed crater statistics,rigorous statistical analyses,and an updated crater chronology function,this study is determined to resolve the relative ages of the Alder crater,Finsen crater,and the mare basalts on the floor of Von Kármán.Our results reveal that while background secondaries and local resurfacing have widely occurred in the study area,affecting age determinations,the statistics are significant enough to conclude that the Alder crater is the oldest among the three targets.This independent constraint is consistent with both the crosscutting relationships of different terrains in this area and global stratigraphic mapping.Our results exclude Alder as a possible contributor of the post-mare deposits at the landing site,appealing for a more systematic stratigraphy study to resolve the provenances of these deposits.
基金support from the National Natural Science Foundation of China (NSFC) through grant numbers 41525015 and 41774186
文摘The Martian ionosphere is produced by a number of controlling processes, including solar extreme ultraviolet radiation (EUV) and X-ray ionization, impact ionization by precipitating electrons, and day-to-night transport. This study investigates the structural variability of the Martian ionosphere with the aid of the radio occultation (RO) experiments made on board the recent Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft. On the dayside, the RO electron density profiles are described by the superposition of two Chapman models, representing the contributions from both the primary layer and the low-altitude secondary layer. The inferred subsolar peak electron densities and altitudes are 1.24×10^5 cm^-3 and 127 km for the former, and 4.28×10^4 cm^-3 and 97 km for the latter, respectively, in general agreement with previous results appropriate for the low solar activity conditions. Our results strengthen the role of solar EUV and X-ray ionization as the driving source of plasma on the dayside of Mars. Beyond the terminator, a systematic decline in ionospheric total electron content is revealed by the MAVEN RO measurements made from the terminator crossing up to a solar zenith angle of 120°. Such a trend is indicative of day-to-night plasma transport as an important source for the nightside Martian ionosphere.
基金supported by the National Water Pollution Control and Management Technology Major Project (No. 2018ZX07110005)the National Natural Science Foundation of China (No. 52170097)the Fundamental Research Funds for Beijing University of Civil Engineering and Architecture (Nos. X18288, X18289 and X20137)。
文摘Citrate (Ct) was chosen as a typical chelator used in the Fe^(2+)-peroxydisulfate (PDS) process to improve sludge dewaterability.The PDS-Fe^(2+)-Ct process exhibited better performance in sludge dewatering than PDS-Fe^(2+).Specifically,with a PDS dosage of 1.2 mmol/g VS,the molar ratio of PDS/Fe^(2+)and Ct/Fe^(2+)were 4:5 and 1:4,respectively,the capillary suction time decreased from 155.8 to 24.8sec,and the sludge cake water content decreased from 82.62%to 64.11%(-0.06MPa).The oxidation led to a reduced negative charge and a decrease in particle size.The enhanced sludge dewaterability and changes of sludge properties were attributed to the decomposition of extracellular polymeric substances,and it was explored by protein,polysaccharide,3D-EEMs,and FT-IR.Additionally,the quenching experiments of radical species demonstrated that SO_(4)-·played a more important role than·OH,and its productivity was improved with the addition of Ct.Moreover,the reasons for the improved productivity of radicals with the addition of Ct were discussed.The results of this study could serve as a basis for improving sludge dewatering using the PDS-Fe^(2+)-Ct process and suggest that the addition of Ct may improve the productivity of SO_(4)-·in the activation o PDS via Fe^(2+).
基金Project supported by National Key R&D Program of China(Grant No.2016YFF0203000)the National Natural Science Foundation of China(Grant Nos.11774167 and 61571222)+2 种基金the Fundamental Research Funds for the Central Universities of China(Grant No.020414380001)the Key Laboratory of Underwater Acoustic Environment,Institute of Acoustics,Chinese Academy of Sciences(Grant No.SSHJ-KFKT-1701)the AQSIQ Technology R&D Program of China(Grant No.2017QK125)
文摘We develop a model for calculating the radiation force on spherically symmetric multilayered particles based on the acoustic scattering approach.An expression is derived for the radiation force on a multilayered sphere centered on the axis of a Gaussian standing wave propagating in an ideal fluid,The effects of the sound absorption of the materials and sound wave on acoustic radiation force of a multilayered sphere immersed in water are analyzed,with particular emphasis on the shell thickness of every layer,and the width of the Gaussian beam.The results reveal that the existence of particle trapping behavior depends on the choice of the non-dimensional frequency ka,as well as the shell thickness of each layer.This study provides a theoretical basis for the development of acoustical tweezers in a Gaussian standing wave,which may benefit the improvement and development of acoustic control technology,such as trapping,sorting,and assembling a cell,and drug delivery applications.
基金Science Foundation of Shenyang Medical College,No.20187076.
文摘BACKGROUND Lisfranc injuries have not received much attention by orthopedic doctors in the past,and there is little related research on the diagnosis and treatment of these injuries.In recent years with the rise in foot and ankle surgery,doctors are now paying more attention to this type of injury.However,there is still a high rate of missed diagnosis due to insufficient attention causing treatment delays or inadequate treatments,which eventually result in greater sequelae;including long-term pain,arthritis,foot deformity etc.In particular,for cases with a mild Lisfranc joint complex injury,the incidence of sequelae is higher.AIM To select an active surgical treatment for an atypical Lisfranc joint complex injury and to evaluate the clinical efficacy of the surgical treatment.METHODS The clinical data of 18 patients,including 10 males and 8 females aged 20-64 years with Lisfranc injuries treated in our department from January 2017 to September 2019 were retrospectively analyzed.All patients were treated with an open reduction and internal fixation method using locking titanium mini-plates and hollow screws or Kirschner wires.X-ray images were taken and follow-up was performed monthly after the operation;the internal fixation was then removed 4-5 mo after the operation;and the American Orthopedic Foot and Ankle Society(AOFAS)score was used for evaluation on the last follow-up.RESULTS All patients were followed up for 6-12 mo.A good/excellent AOFAS score was observed in 88.9%of patients.CONCLUSION For atypical Lisfranc joint complex injuries,active open reduction and internal fixation can be performed to enable patients to obtain a good prognosis and satisfactory functional recovery.
基金supported by the B-type Strategic Priority Program No.XDB41000000funded by the Chinese Academy of Sciences and the pre-research project on Civil Aerospace Technologies No.D020105funded by China's National Space Administration(CNSA).The authors also acknowledge support from the National Natural Science Foundation of China(NSFC)through grants 41904154,41525015,and 41774186.
文摘An important population of the dayside Martian ionosphere are photoelectrons that are produced by solar Extreme Ultraviolet and X-ray ionization of atmospheric neutrals.A typical photoelectron energy spectrum is characterized by a distinctive peak near 27 eV related to the strong solar HeⅡ emission line at 30.4 nm,and an additional peak near 500 eV related to O Auger ionization.In this study,the extensive measurements made by the Solar Wind Electron Analyzer on board the recent Mars Atmosphere and Volatile Evolution spacecraft are analyzed and found to verify the scenario that Martian ionosphere photoelectrons are driven by solar radiation.We report that the photoelectron intensities at the centers of both peaks increase steadily with increasing solar ionizing flux below 90 nm and that the observed solar cycle variation is substantially more prominent near the O Auger peak than near the HeⅡ peak.The latter observation is clearly driven by a larger variability in solar irradiance at shorter wavelengths.When the solar ionizing flux increases from 1 mW·m^-2 to 2.5 mW·m^-2,the photoelectron intensity increases by a factor of 3.2 at the HeⅡ peak and by a much larger factor of 10.5 at the O Auger peak,both within the optically thin regions of the Martian atmosphere.
基金This work is supported by the B-type Strategic Priority Program of the Chinese Academy of Sciences(grant XDB41000000)the pre-research project on Civil Aerospace Technologies of the China National Space Administration(grant D020105).T.L.and J.C.acknowledge support from the National Natural Science Foundation of China through grants 41525015 and 41774186 to J.C.,and grants 41674149 and 41974175 to T.L.X.Z.acknowledges support from the National Science Foundation(grant AST1740921).J.L.acknowledges support from the Open Research Program of the Chinese Academy of Sciences Key Laboratory of Geospace Environment.Z.W.acknowledges support from the Guangdong Basic and Applied Basic Research Foundation(grant 2019A1515110815)the Chinese Academy of Sciences Key Laboratory of Lunar and Deep Space Exploration(grant LDSE201803).We would like to thank the MCD teams for making the MCD 5.3 data sets available online at http://www-mars.lmd.jussieu.fr/mars/access.html.
文摘In recent studies of the Martian atmosphere,strong diurnal variation in the dust was discovered in the southern hemisphere during major dust storms,which provides strong evidence that the commonly recognized meridional transport process is driven by thermal tides.This process,when coupled with deep convection,could be an important part of the short-term atmospheric dynamics of water escape.However,the potential of this process to alter the horizontal distribution of moist air has not been systematically investigated.In this work,we conducted pre-research on the horizontal transport of water vapor associated with the migrating diurnal tide(DW1)at 50 Pa in the upper troposphere during major dust storms based on the Mars Climate Database(MCD)5.3,a state-of-the-art database for Martian atmospheric research that has been validated as simulating the relevant short-period atmospheric dynamics well.We found westward-propagating diurnal patterns in the global water vapor front during nearly all the major dust storms from Martian years(MYs)24 to 32.Statistical and correlation analyses showed that the diurnal transport of water vapor during global and A-season regional dust storms is dominated by the DW1.The effect of the tidal transport of water vapor varies with the types of dust storms in different seasons.During regional dust storms,the tidal transport induces only limited diurnal motion of the water vapor.However,the horizontal tidal wind tends to increase the abundance of daytime water vapor at mid-to low latitudes during the MY 28 southern summer global dust storm while decreasing it during the MY 25 southern spring global dust storm.The tidal transport process during these two global dust storms can induce opposite effects on water escape.
基金supported by the B-type Strategic Priority Program No.XDB4100000funded by the Chinese Academy of Sciences and the pre-research projects on Civil Aerospace Technologies No.D020105 and D020104+1 种基金funded by China’s National Space Administrationthe National Natural Science Foundation of China through grants 41525015,41774186,and 41904154.
文摘Electron pitch angle distributions similar to bidirectional electron conics(BECs)have been reported at Mars in previous studies based on analyses of Mars Global Surveyor measurements.BEC distribution,also termed“butterfly”distribution,presents a local minimum flux at 90°and a maximum flux before reaching the local loss cone.Previous studies have focused on 115 eV electrons that were produced mainly via solar wind electron impact ionization.Here using Solar Wind Electron Analyzer measurements made onboard the Mars Atmosphere and Volatile Evolution spacecraft,we identify 513 BEC events for 19-55 eV photoelectrons that were generated via photoionization only.Therefore,we are investigating electrons observed in regions well away from their source regions,to be distinguished from 115 eV electrons observed and produced in the same regions.We investigate the spatial distribution of the 19-55 eV BECs,revealing that they are more likely observed on the nightside as well as near strong crustal magnetic anomalies.We propose that the 19-55 eV photoelectron BECs are formed due to day-to-night transport and the magnetic mirror effect of photoelectrons moving along cross-terminator closed magnetic field lines.
