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Primary water and oxygen isotope composition are important tools in tracing magma source and evolution. Metamictization of zircon due to U-Th radioactive decay may introduce external secondary water to the crystal, thereby masking the primary water and oxygen isotope signature. Recently, Raman-based screening has been established to select the low-degree metamict zircons. However, such an approach may not be appropriate for ancient samples, in which nearly all zircons are metamict. It was reported that thermal annealing can potentially heal crystals and retrieve primary water content and δ18O information from metamict zircons, given the weaker hydrogen bond of secondary water than that of primary water. Heating experiments at temperatures of 200–1000 °C over a period of 2–10 h reveal that annealing can effectively recover primary water and oxygen isotopes from metamict zircons. Primary water in crystalline and metamict zircons remains intact when heated at 4 h, which represent the optimal annealing treatment condition. Hydrothermally altered zircon is an exception. It only yields the minimum estimate of its primary water contents at 600 °C over a period of >4 h, probably due to partial primary water loss during metamictization for hydrothermal zircons. Moreover, the proportion of low-δ18O (700 °C. This study therefore provides the basis for applying zircon water and δ18O proxies to geologically ancient samples.

Water content and oxygen isotopes in zircon provide crucial constraints on magma source and process, yet they can be significantly modified by zircon metamictization, which causes secondary water absorption into the zircon crystal and the concomitant oxygen isotope changes. Therefore, it is imperative to develop a screening scheme to select the least-metamict zircons for the analyses. We propose a screening scheme based on our study on the Suzhou A-type granite (South China) through integrating Raman spectroscopy, water and trace element measurements, and oxygen isotope analysis. The results show that the primary water content is retained in zircon when the full-width at half maximum (FWHM) is 1007 cm−1 of ν3(SiO4) vibration band, while the primary δ18O is preserved at 1005.5 cm−1 Raman shift. Changes in trace element concentrations in Suzhou zircons are different from previous observations in metamict zircons but most likely related to magma evolution, which implies that trace elements are insensitive to metamictization. Primary δ18O in Suzhou zircons (4.5–6.0‰) fall into the mantle range, indicating a dominant mantle contribution to Suzhou granites. Primary water content was estimated at ca. 650–1400 ppm, significantly higher than those of typical I-type granite (400–736 ppm) and upper mantle-derived zircons (81–177 ppm). The high primary zircon water content was not controlled by the sub-solidus process, temperature, pressure, and cation charge balance but considered to reflect the high-water content in melts. This suggests a hydrous origin for the Suzhou A-type granite, which challenges the conventional view of anhydrous petrogenesis for A-type granites.

Metasomatism by silicate or carbonatite melts can significantly modify the mineral physical and chemical properties, and the hydrogen geochemical behavior during the interaction of olivine and melt remains unclear. In this study, olivine wate content was measured by SIMS on two peridotite xenolith suites. The water content in the silicate-metasomatized olivine increases along with the metasomatism intensity, whereas the opposite trend is present in the carbonatite-metasomatized ones. These results reflect that H enters olivine via silicate metasomatism, whereas it is extracted by carbonatite melts due to its high-water solubility. In addition, as 7Li (more hydrotropic than 6Li) have more similar geochemical behavior to H, 7Li preferentially enter olivine during silicate metasomatism, but remain in the melt during carbonatite metasomatism, resulting in distinct Li isotope behavior during the two different metasomatism. Therefore, the water content of olivine can be used to distinguish metasomatic melts, as well as to explain the δ7Li differentiation.

It is difficult to repair large skull and dural defects. We observed the therapeutic effects of anterolateral thigh flaps with vascular fascia lata for repairing large skull and dural defects.From December 2008 to June 2019, we repaired large skull and dural defects for 28 cases including 12 cases with scalp malignant tumor and 16 cases requiring removal of titanium mesh which had been once placed due to craniocerebral trauma. The scalp malignant tumor invaded full-thickness skull in 12 cases; and invaded cervical lymph nodes, dura mater or brain tissue in 3 cases. In the 12 cases with scalp malignant tumor, the scalp defects of 12 cm × 9 cm to 22 cm × 18 cm and skull defects of 9 cm × 7 cm to 15 cm × 12 cm after radical tumor resection were repaired using anterolateral thigh flaps of 14 cm × 11 cm to 23 cm × 19 cm with fascia lata of 10 cm × 8 cm to 16 cm × 12 cm. Postoperative radiotherapy and chemotherapy were also performed in the 3 cases with tumor metastasis. In the 16 cases requiring removal of titanium mesh, the skull and dural defects of 8 cm × 7 cm to 15 cm × 11 cm after removal of titanium mesh were repaired using anterolateral thigh flaps of 10 cm × 8 cm to 16 cm × 12 cm.In all cases, the transplanted anterolateral thigh flap with fascia lata survived after surgery and no vascular crisis occurred. During the followup of 8 months to 9 years, the flap appearance in the head-repaired area was fine, no external hernia of brain tissue occurred, the appearance of the femoral donor site was acceptable, and femoral muscle strength and movements were normal in all cases. The 12 cases with scalp malignant tumor had no local recurrence or distant metastasis.Repairing the skull and dural defects caused by radical surgery for scalp malignant tumor or removal of titanium mesh using anterolateral thigh flaps with vascular fascia lata, is effective. The appearance in the head-repaired area is fine without external hernia of brain tissue.

Trapped fossil fluids in mineral-hosted fluid inclusions preserve pivotal information on the evolution of paleo geological systems, particularly the hydrothermal mineralization systems. However, identification of the sources of the extracted gases during bulk analysis of fluid inclusions is challenging because multiple generations, types, and phases of fluid inclusions may exist in the same mineral. To better identify the gas sources during stepwise crushing we report an improved gas extraction model of fluid inclusions. Stepwise extracted gases from fluid inclusions in quartz and cassiterite were measured with a quadrupole mass spectrometer and compared with Raman analysis of different types of secondary (SFIs) and primary (PFIs) fluid inclusions. We found that H2O-poor and CO2-rich gases with elevated CO2/CH4 ratios, H2O and formamide-rich gases, and CH4-rich gases were extracted sequentially during stepwise crushing. Such compositional variations of the released gases suggest that the extraction of fluid inclusions starts from SFIs with high vapor-filling degrees (f) and CO2-bearing tri-phase high-f fluid inclusions, which is followed by large liquid-rich SFIs and mid-sized high-f PFIs that are rich in CO2 and formamide, and ends with small CH4-rich low-f PFIs. These findings suggest that the degassing pattern of hydrothermal minerals during stepwise crushing is mostly governed by the physicochemical characteristics of the fluid inclusions, in particular, their vapor-filling degrees, sizes, compositions (which can lead to different inner pressures and densities), and associations with micro-cracks. This updated model of gas release patterns strengthens the theoretical basis for differentiating and identifying the sources of gases extracted during stepwise crushing experiments, which is key to understanding the fluid geochronology and geochemistry of hydrothermal deposits with multi-stage hydrothermal evolution in general.

In this study, a high-precision secondary ion mass spectrometry (SIMS) zircon oxygen isotope ratio analytical protocol is described. The analysis is conducted using a Cameca IMS 1280-HR at the SIMS Laboratory of Guangzhou Institute of Geochemistry, Chinese Academy of Sciences (GIGCAS). Four reference zircons (91,500, Qinghu, TEMORA 2 and Penglai) have been chosen to evaluate the reproducibility (precision) and accuracy. An identical protocol is used for the analyses, with unchanged instrumental parameters and with ion beam intensities kept as identical as possible. The Penglai zircon is used as an external reference material to calibrate the instrumental mass fractionation. The 91,500, Qinghu and TEMORA 2 zircons are used as the unknown samples, which yielded 10.15 ± 0.26‰ (2SD), 5.46 ± 0.24‰ (2SD) and 8.33 ± 0.29‰ (2SD), respectively, all consistent with the recommended values within error (2SD). A half-year long-term precision of 0.44‰ (2SD) is achieved using the Qinghu zircon as a monitoring sample for the routine measurement of zircon 18O/16O ratio, which demonstrates the reliability of this analytical protocol.

The gentle stepwise crushing technique permits progressive extraction of gases from large, irregular, secondary fluid inclusions (SFIs) along micro-cracks to small, regular, liquid-rich primary fluid inclusions (PFIs). Previous studies have verified this general gas release pattern in different hydrothermal minerals based on the agreements between 40Ar/39 Ar ages of the released gases from different crushing stages and the most likely corresponding geological events dated with other methods; and based on the excellent agreements between gas chemistry measured by QMS (quadrupole mass spectrometer) during stepwise crushing and the expected characteristics of SFIs and PFIs in the same samples acquired using Raman spectroscopy. In this study, we applied this QMS-based gentle stepwise crushing technique on ore and gangue minerals from the world-class Yaogangxian tungsten deposit in South China. Gases released from PFIs in cassiterite, wolframite, and quartz from ore-bearing veins show high CH 4, N2, C3H8, and low CO2, C4H10 contents, low CO2/CH4 (≪1) and high N2/Ar (327–861 for ore minerals and 60.7–943 for quartzs from ore veins) ratios, along with multiple organic gaseous species. Their compositions resemble those of gases released from PFIs in quartzs from the Yaogangxian granites which represent magmatic-hydrothermal fluids that exsolved from the granitic magma. However, compared with these exsolved magmatic-hydrothermal fluids, ore mineral PFIs have relatively high He contents which indicate contributions from non-magmatic crustal fluids. This is consistent with high Ca2+, low F− concentrations, and low K+/Na+ (0.21–0.32) ratios observed in fluids in the quartz samples, as well as their relatively low water hydrogen isotopes (δD-H2O = −102 to −59‰). These chemical characteristics, coupled with their magmatic sulfur (δ34S-molybdenite and arsenopyrite = −0.2–1.4‰), methane hydrogen (δD-CH4 = −58 to −42‰), and fluid oxygen (δ18O-H2O = 3.9–5.1‰) isotopic compositions, indicate both magmatic and non-magmatic crustal components in the mineralizing fluids. Based on these observations and the low methane carbon isotope values (δ13C-CH4) in the studied quartz samples, we propose that fluid-rock interactions between the exsolved magmatic-hydrothermal fluids and the metasedimentary wall rocks played an important role in promoting W-Sn precipitation in this ore deposit. This study demonstrates the power of combining QMS-based stepwise crushing technique with traditional geochemical techniques in investigating ore-forming processes.

It is difficult to repair knee deep burn wounds in elderly patients. In this study, we observed the therapeutic effects of descending genicular artery-saphenous artery perforator flaps on knee deep burn wounds in elderly patients. Between December 2013 and February 2018, we repaired knee third-degree burn wounds using descending genicular artery-saphenous artery perforator flaps of 20 × 12 cm to 23 × 13 cm in 56 elderly patients. For the patella and patellar ligament with complete necrosis, the patella and patellar ligament were completely removed, whereas for the patella and patellar ligament with partial necrosis, necrotic parts were removed first. The donor area was repaired using intermediate thickness free skin graft. The 56 patients were 76- to 85 years’ old and all had unilateral knee burn. All flaps survived in the 56 patients. After the follow-up of 2 to 36 months, the flaps were excellent in texture and appearance, and exhibited sensory recovery. In the 8 patients with completely necrotic patella and patellar ligament as well as open knee joint, the weight-bearing function of knee joint was retained, which met patients’ requirements of limb salvage and weight-bearing function. In the other 48 patients with partially necrotic patella and patellar ligament as well as open joint capsule, the postoperative flexion and extension of the knee joint were good. In elderly patients, it is an effective method to repair knee deep burn wounds using the descending genicular artery-saphenous artery perforator flaps.

To investigate regional differences in open access among China, USA and Japan, we presented different test methods in contrast distributions of open access journals in SCI-E. We analyzed quartiles in category and influence of open access journals in basic subjects (mathematics, physics, chemistry) by JCR, found top0.10% papers and highly cited papers according to baselines in ESI. The results show that Chinese scholars approved open access journals better than USA and Japan, the ratio is 6.78%; three countries have significant difference in OA overall distribution; OA articles of China increases significantly since 2008, while Japan is relatively stable growth in mathematics, fluctuating in physics and chemistry; three countries publish more than 30% in top 50% journals in the each subject; Chinese scholars issue more than 50% papers in open access journals of chemistry and mathematics; highly cited papers are mostly interdisciplinary research papers or publishing in interdisciplinary journals. Acceptances to OA journals seem likely to incline to some publisher’s country/territory. KeywordsOpen Access; regional recognition; highly cited; Kruskal-Wallis test; Wilcoxon test

Geometric precision correction of remote sensing image plays a more and more important role in the application of high precision remote sensing. A reference image database is built up based on PostgreSQL, an open-source relation database, and ArcSDE, a widely used spatial data engine. Compared with single reference image, the reference image database has the advantages of managing convenience, lower-cost maintenance and high retrieval efficiency. Meanwhile, the correction accuracy is boasted by Gopfert algorithm , and efficiency is improved by advanced parallel model based on parallel I/O and I/O hidden strategy. Beyond this, combined with MapServer which can rapidly display images, a geometric precision correction system of high performance with dual servers is formed, with which mass production ability is achieved.