特发性黄斑裂孔手术前后黄斑区脉络膜厚度变化

目的:探讨玻璃体切除手术对特发性黄斑裂孔(IMH)黄斑区脉络膜血流的影响及脉络膜微结构变化在黄斑裂孔形成中的作用。方法:选取2014-05/2015-12单眼IMH患者56例56眼纳入研究,所有患者均行三通道平坦部玻璃体切除+吲哚菁绿辅助内界膜剥除+12%C3F8气体填充术。晶状体混浊者联合超声乳化吸出+人工晶状体植入。术前及术后1、3、6mo行EDI SD-OCT检查,记录黄斑中心凹下及距中心凹上方、下方、鼻侧、颞侧各1、3mm处共9个位点的脉络膜厚度。结果:术前黄斑中心凹下脉络膜厚度(SFCT)值为233.43±84.638μm,术后1、3、6mo SFCT分别为242.46±88.199,238.97±89.252,236.71±88.661μm,术后1mo与术前相比明显升高(P<0.05)。距中心凹下方3mm处的脉络膜厚度值(ICT3mm)术前(170.89±57.040μm)与术后1、3、6mo(179.63±62.941、179.74±65.981、180.80±58.379μm)相比呈逐渐增高趋势,但各个测量时间点的ICT3mm值两两比较无差异。距中心凹下方1mm处的脉络膜厚度值(ICT1mm)术前(207.37±67.502μm)与术后1、3、6mo(216.31±80.297、214.54±75.693、205.69±68.697μm)有差异(P<0.05),术后6mo与术后1mo相比有差异(P<0.05)。结论:脉络膜厚度降低可能是黄斑裂孔形成的原因,IMH患者术后脉络膜厚度值变化与位置有关,可能与术中填塞气体的压迫作用有关。

Chinese Hα Solar Explorer(CHASE)——a complementary space mission to the ASO-S

The Chinese HαSolar Explorer(CHASE)is designed to test a newly developed satellite platform and conduct solar observations.The scientific payload of the satellite is an Hαimaging spectrograph(HIS),which can,for the first time,acquire full-disk spectroscopic solar observations in the Hαwaveband.This paper briefly introduces CHASE/HIS including its scientific objectives,technical parameters,scientific application system,etc.The CHASE mission is scheduled to launch in 2021.It will complement the observations by on-orbit solar spacecraft(such as SDO,IRIS,STEREO and PSP),as well as future solar missions of the Solar Orbiter and Advanced Space-based Solar Observatory(ASO-S).

血清淀粉样蛋白A检测对感染性眼内炎诊断的临床价值

目的:探讨血清淀粉样蛋白A(SAA)在感染性眼内炎诊断中的临床应用价值。方法:收集2016-06/2019-03我院就诊的270例患者,其中116例感染性眼内炎患者作为研究组,154例非感染性患者作为对照组。采用胶体金免疫层析法检测SAA水平,用受试者工作特征(ROC)曲线分析诊断效能。结果:感染性眼内炎患者和对照组SAA值中位数分别为14.98、2.56mg/L,两组比较有差异(P<0.001);CRP值和WBC值中位数两组比较均有差异(P<0.001)。SAA、CRP和WBC计数诊断感染性眼内炎的ROC曲线下面积分别为0.772、0.638、0.618,SAA检测取Youden指数最大值所对应的最佳临界值为6.975mg/L,其灵敏度为63.79%,特异度为84.42%。结论:SAA联合CRP和WBC计数有助于提高感染性眼内炎的诊断效能。SAA可为感染性眼内炎的辅助诊断提供有用的参考信息。

Lower gastrointestinal bleeding:Role of 64-row computed tomographic angiography in diagnosis and therapeutic planning

AIM: To determine the value of computed tomographic angiography(CTA) for diagnosis and therapeutic planning in lower gastrointestinal(GI) bleeding.METHODS: Sixty-three consecutive patients with acute lower GI bleeding underwent CTA before endovascular or surgical treatment. CTA was used to determine whether the lower GI bleeding was suitable for endovascular treatment, surgical resection, or conservative treatment in each patient. Treatment planning with CTA was compared with actual treatment decisions or endovascular or surgical treatment that had been carried out in each patient based on CTA findings.RESULTS: 64-row CTA detected active extravasation of contrast material in 57 patients and six patients had no demonstrable active bleeding, resulting in an accuracy of 90.5% in the detection of acute GI bleeding(57 of 63). In three of the six patients with no demonstrable active bleeding, active lower GI bleeding recurred within one week after CTA, and angiography revealed acute bleeding. The overall location-based accuracy, sensitivity, specificity, positive predictive value(PPV) and negative predictive value(NPV) for the detection of GI bleeding by 64-row CTA were 98.8%(249 of 252), 95.0%(57 of 60), 100%(192 of 192), 100%(57 of 57), and 98.5%(192 of 195), respectively. Treatment planning was correctly established on the basis of 64-row CTA with an accuracy, sensitivity, specificity, PPV and NPV of 98.4%(248 of 252), 93.3%(56 of 60), 100%(192 of 192), 100%(56 of 56), and 97.5%(192 of 196), respectively, in a location-based evaluation. CONCLUSION: 64-row CTA is safe and effective in making decisions regarding treatment, without performing digital subtraction angiography or surgery, in the majority of patients with lower GI bleeding.

Excess dietary cholesterol may have an adverse effect on growth performance of early post-larval Litopenaeus vannamei

One experiment was conducted to determine the nutritive value of cholesterol for post-larval shrimp, Litopenaeus vannameL Four isoenergetic and isonitrogenous diets supplemented with four levels of cholesterol （D1, D2, D3 and D4 with 0, 0.5%, 1% and 2% cholesterol, respectively） were fed to triplicate groups of L. vannamei shrimp （mean initial wet weight 0.8 mg） for 27 days. After the trial, shrimp fed the D1 diet had the best growth performance （final body weights： FBW; weight gain： WG; specific growth rate： SGR）, while there was no significant difference between diet treatments with respect to survival. The whole body crude protein level in the shrimp decreased with the increase in dietary cholesterol levels, while the whole body crude lipid level in shrimps in the D4 diet treatment was significantly higher （P 〈 0.05） than in other diet treatments. Dietary analysis indicated that the D1 diet contained 0.92% cholesterol prior to supplementation, which may have satisfied the dietary cholesterol requirement of post-larval L. vannamei; excess dietary cholesterol may thus lead to adverse effects on the growth performance of post-larval shrimp.

Outcomes of percutaneous coronary intervention in patients ≥ 75 years： one-center study in a Chinese patient group

Objective To investigate the clinical and perioperative characteristics of patients ≥ 75 who undergoing percutaneous coronary intervention （PCI） and to evaluate the risk factors related to short-term post-PCI mortality in this specific patients group. Methods 1,035 consecutive subjects who underwent PCI from December 2011 to November 2013 were divided into four categories： （1） patients with stable angina （SA） 〉 75 years （n = 58）; （2） patients with SA 〈 75 years （n = 218）; （3） patients with acute coronary syndrome （ACS） ≥ 75 years （n = 155）; （4） patients with ACS 〈 75 years （n - 604）. A multivariable logistic regression analysis was conducted to detect risk factors of six-month mortality in patients ≥ 75 years who had undergone PCI. Clinical comorbidities, in-hospital biochemical indicators, perioperative data, in-hospital and six-month outcomes were analyzed and compared among the four groups. Results Compared with the younger group, pa- tients 〉 75 years were more likely to have hypertension, history of stroke, chronic obstructive pulmonary disease, peripheral vascular disease, cardiogenic shock and malignant mxhythmia, and they were admitted to hospital with relative lower weight, hemoglobin, albumin, triglyceride, higher creatinine, uric acid, urea nitrogen and pro-BNP. Left main artery lesions, multi-vessel, calcified lesions, chronic totally occlusion were also more likely to be seen in the elderly group. Univariate analysis revealed that age 〉 85 years, cardiogenic shock or severe arrhythmia at ad- mission, emergency PCI, prior stroke and chronic kidney disease were related to six-month mortality in elderly patients 〉 75 years who underwent PCI. Multivariable logistic regression showed that cardiogenic shock or severe arrhythmia at admission, chronic kidney disease and prior stroke were independent risk factors predicting six-month mortality in elderly patients 〉 75 years who had undergone PCI. Conclusions Our data showed that, compared with patients under 75 years, elderly patients （〉 75 years） who had undergone PCI had a relative higher risk of mortality, and more often accompanied with multi-comorbidities, severer admission conditions and complex coronary lesions. Better evaluation of risk factors and more intensively care should be taken to patients 〉 75 years who had undergone PCI therapy to reduce complications.

Effect of Chinese national holidays and weekends versus weekday admission on clinical outcomes in patients with STEMI undergoing primary PCI

Background Data regarding the influence of weekends and Chinese national holiday＇s admission on the outcomes of patients with ST-elevated myocardial infarction （STEMI） is lacking. This study sought to investigate the effect of Chinese national holidays and weekend admission on outcomes in patients with STEMI undergoing primary percutaneous coronary intervention （PPCI）. Methods Patients pre- senting with STEMI within 12 h of symptom onset who underwent PPCI were retrospectively enrolled. The primary outcome of in-hospital mortality and major adverse cardiovascular events in patients presenting Chinese national holiday＇s and weekends versus weekdays was evaluated. Results A total of 441 STEMI patients were enrolled in this study. Of these, 129 （29.3%） patients were admitted during Chinese national holidays and weekends and 312 （70.7%） during weekdays. Patients admitted during holidays and weekends were more likely to present with Killip class Ⅲ-Ⅳ. Patients admitted during holidays and weekends experienced a significantly longer door-to-baUoon time, symptom onset-to-door time as well as symptom onset-to-balloon time. The in-hospital mortality between patients presenting holidays and weekends versus weekdays was comparable. However, patients admitted during holidays and weekends have a signitieantly higher rate of in-hospital major adverse cardiovascular events. Multivariate analysis demonstrated that holidays and weekends admission was independ- ently associated with adverse outcomes. Conclusions In China, STEMI patients undergoing PPCI during national holidays and weekends have worse in-hospital outcomes compared to those admitted during weekdays. These findings suggest that continuous efforts should be undertaken to enhance the Chinese healthcare system and to ensure that comparable outcomes are achieved for all STEMI patients regardless of time of presentation.

Free autologous internal limiting membrane transplantation in the treatment of large macular hole

We evaluated the clinical efficacy of free internal limiting membrane(ILM) flap transplantation for the treatment of large macular hole over 500 μm in 42 consecutive patients. Quantified evaluation of the post-operative macular anatomy restoration was performed by spectral-domain optical coherence tomography in the 12 mo follow-up. The results showed 41 eyes achieved successful closure(97.6%). Postoperative best corrected visual acuity, ellipsoid layer, and external limiting membrane disruption were significantly improved at all follow-up time points. The central foveal thickness was significantly higher at 1 mo. We concluded that free ILM flap transplantation proves to be effective to achieve anatomical and functional improvement for the treatment of large macular hole.

Comparison of demographic features and laboratory parameters between COVID-19 deceased patients and surviving severe and critically ill cases

BACKGROUND Coronavirus disease 2019(COVID-19) has been far more devastating than expected, showing no signs of slowing down at present. Heilongjiang Province is the most northeastern province of China, and has cold weather for nearly half a year and an annual temperature difference of more than 60℃, which increases the underlying morbidity associated with pulmonary diseases, and thus leads to lung dysfunction. The demographic features and laboratory parameters of COVID-19 deceased patients in Heilongjiang Province, China with such climatic characteristics are still not clearly illustrated.AIM To illustrate the demographic features and laboratory parameters of COVID-19 deceased patients in Heilongjiang Province by comparing with those of surviving severe and critically ill cases.METHODS COVID-19 deceased patients from different hospitals in Heilongjiang Province were included in this retrospective study and compared their characteristics with those of surviving severe and critically ill cases in the COVID-19 treatment center of the First Affiliated Hospital of Harbin Medical University. The surviving patients were divided into severe group and critically ill group according to the Diagnosis and Treatment of New Coronavirus Pneumonia(the seventh edition).Demographic data were collected and recorded upon admission. Laboratory parameters were obtained from the medical records, and then compared among the groups.RESULTS Twelve COVID-19 deceased patients, 27 severe cases and 26 critically ill cases were enrolled in this retrospective study. No differences in age, gender, and number of comorbidities between groups were found. Neutrophil percentage(NEUT%), platelet(PLT), C-reactive protein(CRP), creatine kinase isoenzyme(CK-MB), serum troponin I(TNI) and brain natriuretic peptides(BNP) showed significant differences among the groups(P = 0.020, P = 0.001, P < 0.001, P = 0.001, P < 0.001, P <0.001, respectively). The increase of CRP, D-dimer and NEUT% levels, as well as the decrease of lymphocyte count(LYMPH) and PLT counts, showed significant correlation with death of COVID-19 patients(P = 0.023, P = 0.008, P = 0.045, P = 0.020, P = 0.015, respectively).CONCLUSION Compared with surviving severe and critically ill cases, no special demographic features of COVID-19 deceased patients were observed, while some laboratory parameters including NEUT%, PLT, CRP, CK-MB, TNI and BNP showed significant differences. COVID-19 deceased patients had higher CRP, D-dimer and NEUT% levels and lower LYMPH and PLT counts.

A new multi-wavelength solar telescope: Optical and Near-infrared Solar Eruption Tracer (ONSET)

A new multi-wavelength solar telescope, the Optical and Near-infrared Solar Eruption Tracer （ONSET） of Nanjing University, has been constructed. It was fabricated at the Nanjing Institute of Astronomical Optics ＆ Technology, and the oper- ation is jointly administered with Yunnan Astronomical Observatory. ONSET is able to observe the Sun in three wavelength windows： He I 10830 A, Ha and white-light at 3600 A and 4250 A, which are selected in order to simultaneously record the dynam- ics of the corona, chromosphere and photosphere respectively. Full-disk or partial-disk solar images with a field of 10~ at three wavelengths can be obtained nearly simultane- ously. It is designed to trace solar eruptions with high spatial and temporal resolutions. This telescope was installed at a new solar observing site near Fuxian Lake in Yunnan Province, southwest China. The site is located at E102N24, with an altitude of 1722 m. The seeing is stable and has high quality. We give a brief description of the scientific objectives and the basic structure of ONSET. Some preliminary results are also pre- sented.

Dependence of the length of solar filament threads on the magnetic configuration

High-resolution Ha observations indicate that filaments consist of an as- sembly of thin threads. In quiescent filaments, the threads are generally short, whereas in active region filaments, the threads are generally long. In order to explain these observational features, we performed one-dimensional radiative hydrodynamic sim- ulations of filament formation along a dipped magnetic flux tube in the framework of the chromospheric evaporation-coronal condensation model. The geometry of a dipped magnetic flux tube is characterized by three parameters, i.e., the depth （D）, the half-width （w） and the altitude （h） of the magnetic dip. A survey of the parame- ters in numerical simulations shows that when allowing the filament thread to grow in 5 days, the maximum length （Lth） of the filament thread increases linearly with w, and decreases linearly with D and h. The dependence is fitted into a linear function Lth = 0.84w --0.88D - 2.78h ＋ 17.31 （Mm）. Such a relation can qualitatively explain why quiescent filaments have shorter threads and active region filaments have longer threads.

铝−共晶镓铟锡复合材料水解制氢

提出一种利用铝和液态金属共晶镓铟锡(eGIS)持续产生氢气的新方法。以带有盲孔的圆柱体铝作为盛放液态金属的容器,通过水解释放氢气,而以eGIS作为触发反应的窗口,促进反应的进行。同时,对半固态Al−eGIS复合材料的显微组织、水解演化和产氢性能进行研究。结果表明,当eGIS沿晶界扩散到多晶铝中时,液态金属发生脆化现象,提高了水解过程中复合材料的反应活性,同时观察到In3Sn和InSn4第二相的形成,其有助于加快铝的水解。此外,Al−10wt.%eGIS和Al−20wt.%eGIS复合材料的水解转化率接近100%。样品应用于质子交换膜燃料进行性能测量,在0.54 W输出功率下稳定供电110 min。

Why are halo coronal mass ejections faster?

Halo coronal mass ejections （CMEs） have been to be significantly faster than normal CMEs, which is a long-standing puzzle. In order to solve the puzzle, we first investigate the observed properties of 31 limb CMEs that clearly display loopshaped frontal loops. The observational results show a strong tendency that slower CMEs are weaker in white-light intensity. Then, we perform a Monte Carlo simulation of 20000 artificial limb CMEs that have an average velocity of ～523km s -1. The Thomson scattering of these events is calculated when they are assumed to be observed as limb and halo events, respectively. It is found that the white-light inten-sity of many slow CMEs becomes remarkably reduced when they turn from being viewed as a limb event to being viewed as a halo event. When the intensity is below the background solar wind fluctuation, it is assumed that they would be missed by coronagraphs. The average velocity of ＂detectable＂ halo CMEs is ～922km s -1, very close to the observed value. This also indicates that wider events are more likely to be recorded. The results soundly suggest that the higher average velocity of halo CMEs is due to that a majority of slow events and some of narrow fast events carrying less material are so faint that they are blended with the solar wind fluctuations, and therefore are not observed.

Some interesting topics provoked by the solar filament research in the past decade

Solar filaments are an intriguing phenomenon,like cool clouds suspended in the hot corona.Similar structures exist in the intergalactic medium as well.Despite being a long-studied topic,solar filaments have continually attracted intensive attention because of their link to coronal heating,coronal seismology,solar flares and coronal mass ejections(CMEs).In this review paper,by combing through the solar filament-related work done in the past decade,we discuss several controversial topics,such as the fine structures,dynamics,magnetic configurations and helicity of filaments.With high-resolution and highsensitivity observations,combined with numerical simulations,it is expected that resolving these disputes will definitely lead to a huge leap in understanding the physics related to solar filaments,and even shed light on galactic filaments.

Chaos-induced resistivity of collisionless magnetic reconnection in the presence of a guide field

One of the most puzzling problems in astrophysics is to understand the anomalous resistivity in collisionless magnetic reconnection that is believed extensively to be responsible for the energy re- lease in various eruptive phenomena. The magnetic null point in the reconnecting current sheet, acting as a scattering center, can lead to chaotic motions of particles in the current sheet, which is one of the possible mechanisms for anomalous resistivity and is called chaos-induced resistivity. In many interest- ing cases, however, instead of the magnetic null point, there is a nonzero magnetic field perpendicular to the merging field lines, usually called the guide field, whose effect on chaos-induced resistivity has been an open problem. By use of the test particle simulation method and statistical analysis, we investigate chaos-induced resistivity in the presence of a constant guide field. The characteristics of particle motion in the reconnecting region, in particular, the chaotic behavior of particle orbits and evolving statistical features, are analyzed. The results show that as the guide field increases, the radius of the chaos region increases and the Lyapunov index decreases. However, the effective collision frequency, and hence the chaos-induced resistivity, reach their peak values when the guide field approaches half of the character- istic strength of the reconnection magnetic field. The presence of a guide field can significantly influence the chaos of the particle orbits and hence the chaos-induced resistivity in the reconnection sheet, which decides the collisionless reconnection rate. The present result is helpful for us to understand the micro- physics of anomalous resistivity in collisionless reconnection with a guide field.

Can we determine the filament chirality by the filament footpoint location or the barb-bearing？

We attempt to propose a method for automatically detecting the solar filament chirality and barb beating. We first introduce the concept of an unweighted undirected graph and adopt the Dijkstra shortest path algorithm to recognize the filament spine. Then, we use the polarity inversion line （PIL） shift method for measuring the polarities on both sides of the filament, and employ the connected components labeling method to identify the barbs and calculate the angle between each barb and the spine to determine the bearing of the barbs, i.e., left or right. We test the automatic detection method with Ha filtergrams from the Big Bear Solar Observatory （BBSO） Ha archive and magnetograms observed with the Helioseismic and Magnetic Imager （HMI） on board the Solar Dynamics Observatory （SDO）. Four filaments are automatically detected and illustrated to show the results. The barbs in different parts of a filament may have opposite bearings. The filaments in the southern hemisphere （northern hemisphere） mainly have left-bearing （fight- bearing） barbs and positive （negative） magnetic helicity, respectively. The tested results demonstrate that our method is efficient and effective in detecting the bearing of filament barbs. It is demonstrated that the conventionally believed one-to-one correspondence between filament chirality and barb bearing is not valid. The correct detection of the filament axis chirality should be done by combining both imaging morphology and magnetic field observations.

Diagnostics of Ellerman bombs with high-resolution spectral data

Ellerman bombs （EBs） are tiny brightenings often observed near sunspots. The most impressive characteristic of EB spectra is the two emission bumps in both wings of the Hα and Ca II 8542 A lines. High-resolution spectral data of three small EBs were obtained on 2013 June 6 with the largest solar telescope, the 1.6 m New Solar Telescope at the Big Bear Solar Observatory. The characteristics of these EBs are analyzed. The sizes of the EBs are in the range of 0.3＂ - 0.8＂ and their durations are only 3-5 min. Our semi-empirical atmospheric models indicate that the heating occurs around the temperature minimum region with a temperature increase of 2700- 3000 K, which is surprisingly higher than previously thought. The radiative and kinetic energies are estimated to be as high as 5 × 1025 - 3.0 × 10^26 erg despite the small size of these EBs. Observations of the magnetic field show that the EBs just appeared in a parasitic region with mixed polarities and were accompanied by mass motions. Nonlinear force-free field extrapolation reveals that the three EBs are connected with a series of magnetic field lines associated with bald patches, which strongly implies that these EBs should be produced by magnetic reconnection in the solar lower atmosphere. According to the lightcurves and the estimated magnetic reconnection rate, we propose that there is a three phase process in EBs： pre-heating, flaring and cooling phases.

MHD Seismology of a loop-like filament tube by observed kink waves

We report and analyze observational evidence of global kink oscillations in a solar filament as observed in Ha by instruments administered by National Solar Observatory （NSO）/Global Oscillation Network Group （GONG）. An M1.1-class flare in active region （AR） 11692 occurred on 2013 March 15 and induced a global kink mode in the filament lying towards the southwest of AR 11692. We find periods of about 61-67 minutes and damping times of 92-117 minutes at positions of three ver- tical slices chosen in and around the filament apex. We find that the waves are damped. From the observed period of the global kink mode and damping timescale using the theory of resonant absorption, we perform prominence seismology. We estimate a lower cut-off value for the inhomogeneity length scale to be around 0.34-0.44 times the radius of the filament cross-section.

Effect of Al_(2)O_(3)/SiO_(2) ratio on morphology of complex calcium ferrite

Al_(2)O_(3) and SiO_(2) greatly influence the formation of complex calcium ferrite,which is the main bonding phase in high basicity sinters.The effects of Al_(2)O_(3)/SiO_(2) ratios on the morphology of complex calcium ferrite were studied.The main mineral phases in the samples with different Al_(2)O_(3)/SiO_(2) ratios were CaFe_(2)O_(4) with a solid solution of Si or Al atoms and the silico-ferrite of calcium and aluminum.The results showed that the morphology of the complex calcium ferrite changed from lumpy to plate-like and acicular with increases in the SiO_(2) content and the Al_(2)O_(3)/SiO_(2) ratio.When the content of SiO_(2) was 4 wt.%,the main calcium ferrite morphology was acicular,and the number of macropores in the samples increased with the Al_(2)O_(3)/SiO_(2) ratio increasing.The first-principles analysis of the calcium ferrite crystal structure showed that adding SiO_(2) and Al_(2)O_(3) changed the growth mechanism of the CaFe_(2)O_(4) crystal,promoting the formation of platy and acicular complex calcium ferrite.The size of calcium ferrite was significantly smaller due to the increase in CaO-Fe_(2)O_(3)-SiO_(2)-Al_(2)O_(3) viscosity with increasing the Al_(2)O_(3)/SiO_(2) ratio.