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Papua New Guinea (PNG) is located at the convergence edge of the Pacific Plate and the Indo-Australian Plate, consisting of three units. There are three chromium mineralization types in PNG. Based on national-scale geochemical mapping in PNG during 2015–2018, 1399 samples of stream sediments were collected from Highland Region, Papua Peninsula, and New Guinea Islands. This paper preliminarily studied chromium’s geochemical background, spatial distribution characteristics, and geochemical anomalies. The chromium concentration ranged from 3 ppm to 74,600 ppm, with a median value of 145 ppm, which was higher than the upper crustal abundance of chromium and the chromium geochemical baseline of Europe, Australia, North America, and China. In terms of stream sediment samples in different tectonic units, as mafic–ultramafic magmatic rocks are widely developed, the median chromium values of the New Guinea Orogen, including the Papuan Fold Belt, the New Guinea Thrust Belt, the Finisterre Terrane, the Aure Fold Belt, the Eastern Fold Belt, and the Eastern Papuan Composite Terrane, were higher than the value of the Melanesian Arc. The ophiolitic complexes, such as the April ophiolite, the Marum ophiolite, and the Papua ultramafic belt, significantly correlated with the higher chromium concentration. Eleven chromium high anomalies with mineralization potential were delineated, including three laterite and podiform prospecting areas and eight placer prospecting areas. Based on the chromium–nickel integrated anomaly map, comprehensive exploration and exploitation of nickel and chromium can be carried out in 1 and 11 high anomaly areas related to lateritic mineralization.

Background Colon adenocarcinoma (COAD) is one of the most common malignancies worldwide. Genomic instability is one of the hallmarks of colon cancer and is associated with prognosis. Nevertheless, the impact of genome instability-associated long non-coding RNAs (lncRNAs) along with their clinical significance in cancers has remained mostly unexplored. Methods In this study, a mutator hypothesis-derived computational frame integrating the somatic mutation profiles and lncRNA expression profiles in a tumor genome was developed, which enabled the identification of 137 novel genomic instability-associated lncRNAs in colon cancer. Subsequently, a genome instability-derived lncRNA signature (GILncSig) segregated the patients into low- and high-risk groups with prominent differences in outcomes. Results Combined with the overall survival data, we established 6 six lncRNA-based signature to predict prognosis, which were LINC00896, AC007996.1, NKILA, AP003555.2, MIRLET7BHG, and AC009237.14. We found that the expression level of PD-L1 (CD274) and somatic mutations in the high-risk group were higher than those in the low-risk group. This suggests that high-risk patients may be sensitive to immunotherapy. We further found that the prognosis of patients in the high-risk group was significantly lower than that of patients in the low-risk group, and that patients' prognosis was likely to be worse as the patient's risk score increased. Conclusions In conclusion, this study explores the role of lncRNAs in genomic instability and cancer prognosis and provides a new idea for the prognostic prediction of colon cancer.

Geochemical baselines are crucial to explore mineral resources and monitor environmental changes. This study presents the first Laos geochemical baseline values of 69 elements. The National-scale Geochemical Mapping Project of Lao People’s Democratic Republic conducted comprehensive stream sediment sampling across Laos, yielding 2079 samples collected at 1 sample/100 km2, and 69 elements were analyzed. Based on the results of LGB value, R-mode factor analysis, and scatter plot analysis, this paper analyzes the relationship between the 69 elements and the geological background, mineralization, hypergene processes and human activities in the study area. The median values of element contents related to the average crustal values were: As, B, Br, Cs, Hf, Li, N, Pb, Sb, Zr, and SiO2, >1.3 times; Ba, Be, Cl, Co, Cr, Cu, F, Ga, Mn, Mo, Ni, S, Sc, Sr, Ti, Tl, V, Zn, Eu, Al2O3, Tot.Fe2O3, MgO, CaO, and Na2O

Geochemical background is the basis of anomaly evaluation in mineral exploration and environmental investigation. However, the background value obtained from secondary media is inevitably affected by weathering, transportation, and sorting, which leads to secondary depletion or enrichment of chemical elements. This problem can be avoided by the geochemical mapping of the exposed crust. In this paper, more than 38,000 samples of rocks data were collected, and an original method was presented for the first time to produce the cobalt geochemical map of exposed crust across the whole of China. Using a geological map grid of 1:200,000 as the basic calculation unit, the area and content of rock types in each unit were calculated, and then the grid was assigned using the area-weighted average method. Based on this, an geochemical contour map was drawn in ArcGIS. The results show that the median of the exposed crust is 9.74 mg/kg, which is lower than that of the whole crust and soils. This value is explained by the vertical heterogeneity of the crust and the secondary enrichment, respectively. Co anomalies and anomalous centers of exposed crust are distributed in southwest, north, and northwest China, where they are primarily related to Permian Emeishan Large Igneous Province (ELIP), Pacific plate, and the big mantle wedge (BMW), Archean metamorphic basic rocks, and ophiolite belts.

The Changkeng–Fuwan Au-Ag deposit is representative in South China, which is located in the southwest of the Qin–Hang metallogenic belt (QHMB). The Au and Ag orebodies are located in the same altered fracture zone, forming independent gold and silver orebodies respectively, with the characteristics of “upper gold and lower silver” in space. Three metallogenic stages have been identified: the pyrite–quartz–sericite stage, the polymetallic sulfide stage, and the quartz–calcite stage. The fluid inclusions (FIs) from the deposit are the two-phase liquid-rich (type I) and the pure liquid FIs (type II). The microthermometric measurements of type I FIs are characterized by temperatures of 158–282 °C and 146–289 °C and salinities of 0.35–9.88 wt.% NaCl equiv. and 0.18–11.70 wt.% NaCl equiv. The H, O, He, and Ar isotopic data show that the ore-forming fluids of the deposit were derived from a mixture of magmatic and meteoric fluids. The C and O isotopic data suggest that the carbon of the fluid may derive from a magmatic source. The S and Pb isotopic data indicate that the primary source of the metals in the Changkeng–Fuwan deposit may be a magma source. Based on the geological characteristics, FI microthermometry, and isotope data (C, H, O, He, Ar, S, and Pb), we propose that the Changkeng–Fuwan deposit should be classified as a far-source low-temperature magmatic–hydrothermal deposit.

The objective of this work was to estimate the influence of climate variability on viticultural zoning and variety regionalisation in China in the past 50 years. A multicriteria climatic indices system, which includes Frost-Free Season (FFS), Dryness Index (DI), and Extreme Low Temperature (ELT), was used to define climatic suitable areas and classify different climate zones for wine grape-growing in China. The Accumulated Effective Temperature (AET) was used as an index of variety regionalisation. Indices were calculated based on daily climatic observations from national ground weather stations throughout China from between 1967 and 2016. The variation trends were analysed by Sen’s slope and Mann-Kendall non-parametric tests in 13 representative wine growing sites. Based on the studied criteria, the suitable viticultural zone exhibited a continuous northward expansion with an average increase of 0.204 million km2/decade, largely due to increasing FFS. A significant increase of FFS was detected in most representative sites, with almost no detectable change of DI during the growing season. The analysis also revealed that the North East Region, Inner Mongolia Region, and Xinjiang Region are the three most profitable wine regions. Movement of the soil-burying line was limited to Shandong and Hebei provinces. Although the suitable viticultural zone increased, the data also revealed a decrease in the area for high quality wine production when considering varietal suitability. These results have important implications for understanding both new opportunities and challenges under changing climate and the latter’s effects on viticultural viability in China. They can also help guide stakeholders to develop adaptive strategies for maintaining the profitability of currently used regions and for developing new regions for viticulture.

In recent years, mineral resources near the surface are becoming scarce, causing focused mineral exploration on concealed deposits in covered terrains. In northern China, covered terrains are widespread and conceal bedrock sequences and mineralization. These represent geochemical challenges for mineral exploration in China. As a deep-penetrating geochemical technology that can reflect the information of deep anomalies, the fine-grained soil prospecting method has achieved ideal test results in arid Gobi Desert covered terrain, semi-arid grassland covered terrain, and alluvium soil covered terrain of northern China. The anomaly range indicated by the fine-grained soil prospecting method is very good with the known ore body location. The corresponding relationship can effectively indicate deep ore bodies and delineate anomalies in unknown areas. Overall, the fine-grained soil prospecting method can be applied to geochemical prospecting and exploration in covered terrains.

Colon adenocarcinoma (COAD) is globally one of the most frequently occurring malignant tumors. The patients' 5-year survival rate with colon cancer was poor. There is a usual form of mRNA modification called N6-methyl adenosine (m6A). It is adjusted by the m6A RNA methylation modulator. Nevertheless, few studies of COAD can fully discuss m6A-related lncRNAs' prognostic function.From The Cancer Genome Atlas (TCGA) database, this study of COAD samples discussed 23 m6A regulator-related lncRNAs systemically. 2 m6A patterns with various clinical results were recognized, and a remarkable correlation between various m6A clusters and tumor immune microenvironment was discovered.According to prognostic analysis, cluster1 had a higher immune checkpoint programmed death-ligand 1 (PD-L1) expression and a better prognosis. A 6 m6A-related lncRNAs model was constructed through least absolute shrinkage and selection operator (LASSO), univariate, multivariate Cox regression and stratified analysis. The outcomes reported that compared with the low-risk group, high-risk groups that were based on model closely were related to poor overall survival (OS). The study ensured a risk model consisting of 6 m6A-related lncRNAs as independent prognosis predictors. For the expression differences between the two groups, Genomes Pathway Analysis, Kyoto Encyclopedia of Genes (KEGG) and Gene Ontology (GO) biological process analyses were conducted. In addition, on the basis of full analysis of OS, a nomogram based on gender, age, lncRNA feature and the stage was constructed. One year, two years, and three years are the periods when the calibration chart performed best.The outcomes of the study confirmed the underlying function of m6A-related lncRNAs and offered fresh perspectives to COAD prognosis.

There are many Late Triassic mafic–ultramafic intrusions in the Hongqiling magmatic Ni–Cu sulfide deposit, Northeast China. Research on magma evolution leading to formation of these mafic–ultramafic intrusions is of great significance for understanding the mantle beneath Northeast China and associated Ni–Cu mineralization. A trace element study of the No. 1, 3, and 7 intrusions in the Hongqiling deposit reveals that these mafic–ultramafic intrusions are characterized by enrichment of incompatible elements, which however cannot be interpreted by subduction modification. Furthermore, model of batch partial melting of depleted mantle accompanied by upper crustal contamination can simulate the trace element patterns of these mafic–ultramafic intrusions, but partial melting of depleted mantle accompanied by lower crustal contamination model cannot work. In addition, Sr–Nd isotopic compositions of the Hongqiling No. 1, 3, and 7 intrusions also indicate that crustal contamination could have occurred mainly during the magma ascent. Consequently, a possible scenario for the magma evolution is that the primary mafic–ultramafic magma was derived from batch partial melting of a depleted mantle, and then contaminated by Cambrian–Ordovician metamorphic rocks of the Hulan Group during ascent. We conclude that the mantle source contained no significant crustal component in the Late Triassic and was also independent of substantial contribution from subducted material, and therefore the Mesozoic large-scale lithospheric delamination beneath eastern China may happen after a period of time of the Late Triassic.

This paper proposes using a simulated annealing (SA) calculation to perform one-dimensional inversion of Geomagnetic Depth Sounding (GDS) to obtain the conductivity information of the lower mantle beneath the Tarim area, to calculate the temperature of the lower mantle according to the relevant formula of the petrophysical experiment, and to provide evidence of the existence of the Tarim mantle plume. The data used for inversion originate from the China Geomagnetic Network Center. This article uses theoretical data to prove that the simulated annealing algorithm can invert the true conductivity model when the data do not contain noise. However, when the data contain noise, it is more accurate to use the statistical expected value of the high-quality conductivity model during the simulated annealing inversion process as the optimal conductivity model rather than the classic simulated annealing algorithm. The simulated annealing inversion results of only four stations in Tarim area show that the conductivity of the top of the lower mantle and the upper part of the mantle transition zone in Tarim area is higher than the global average, and it is speculated that the temperature is 150k&ndash, 450k higher than the global average. This is important evidence for the existence of the mantle plume beneath the Tarim Basin.

The objective of this work was to perform preliminary assessment of the performance of different models for the simulation of three main phenology stages (budburst, flowering, and veraison) of grapevine in China. This work utilized observations from five representative wine regions (Changli, Laixi, Shangri-La, Xiaxian, and Yanqi) and four widely cultivated grape cultivars (Cabernet Sauvignon, Cabernet Franc, Merlot, and Chardonnay) in China. The corresponding daily temperature data were used to simulate the timing of grape phenology stages based on the different phenological models. The dates based on the simulation and the actual dates were compared and the performance of these models were assessed for different cultivars and wine regions. The GDD10 model exhibited the best performance for budburst simulation in soil-burying regions, irrespective of the cultivar and location. For flowering and veraison, the optimal model varied in performance between cultivars and locations, and non-linear models exhibited better performance than linear models. In general, the performance of these models was better for the latter two stages than for budburst. The models with relatively good performance were selected for further calibration using these limited Chinese observations. The impact of soil-burying management on budburst simulation was also estimated. These results highlight the strengths of some phenological models for use in China. This study also reiterates the strong need for establishment of a grapevine phenology observation network in China to obtain more comprehensive data.

Geochemical gene is a new technique presented recently and its history is described and classified into three stages up to the present. To construct a geochemical gene, five steps are suggested as selection of elements, determination of reference values, spectral line and codes, calculation of similarity, and sequence of elements. The essence of the geochemical gene is similar to the quantitative description of the spider diagram or REE pattern regardless of the compositional closure effect. According to the construction steps, 7 geochemical genes have been constructed by now as the lithogenes of LG01, LG02, and LG03, the metallogenes of MGAu and MGW, and the rare earth elemental genes of REEG01 and REEG02. Lots of weathering profiles developed on different lithological rocks in China have been studied to test the gene properties of heredity and inheritance and the results indicate that the geochemical genes can keep steady during rocks' weathering according to the similar gene criterion of ≥80% on gene similarity. Moreover, the LG01 and LG03 are more stable than LG02, the LG03 may be steadier than LG01, and the REEG01 is more stable than REEG02 during rocks' weathering. The gene similarity between a sample and the ideal acidic rock is called the sample's acidic similarity which can be used as a tool to classify samples and discriminate their provenances compositionally on the LG01 and LG03 lithogenes. The gene similarity between a sample and the ideal ore is called the sample's mineralization similarity which can be viewed as an integrated index to determine a sample with or without mineralization on the field of geochemical exploration. Based on the geochemical gene database constructed from the regional geochemical survey data, the gene similarity can be used to trace a geological material where it is from. To code geochemical genes and calculate gene similarities between samples, a software named as GGC (Geochemical Gene Coding) is developed non-commercially.

Nanogeology is a subject that is a combination of geology and nanoscale science, and it has been a frontier field in recent years. It is also a new subject with the features of intersectionality and multidisciplinary. Digging deeper into geological problems and nanoscale phenomena helps better revealing the more essential mechanisms and processes in geological science, which is also an evitable path in the development of geology. In this paper, we elaborate the concept, feature and main subdisciplines, and summarize three stages of nanogeology development from preliminary research in the 1990s to subject formation in China. After summarizing the researchers’ achievements in this field, we illustrate some primary research progresses of nanogeology in China as eight subdisciplines. On the basis of the above content, we propose the development prospect of nanogeology in China. There are many geologic problems with scientific values and economic benefits, such as research of geologic fundamental problems, resource exploration and development, mechanism study and prediction of geological activities (disasters), mechanism research and management of environmental pollution and others. Nanogeology has a great potential in China to solve all of these problems. As a result, the theories and methods of nanogeology will become enriching and advanced. It offers important theoretical basis and technological methods to deal with major issues concerning the national economy and the people’s livelihoods, such as the prediction of geological activities, as well as resource distribution and its exploration and utilization.

Mineral deposits concealed by thick cover sequences present special problems for geochemical exploration. A variety of penetrating geochemical methods have been developed in the last few decades to explore for buried deposits. The theoretical basis of the mechanism by which metals migrate upward from buried deposits through the cover to the surface is still not fully understood. One hypothesis is that metal particles or metal elements could be carried onto bubbles or micro-flow of geogas and migrate upward to the surface. After years of study, nano-scale metal-bearing particles have been widely observed in geogas samples from different kinds of concealed deposits. However, the occurrence of these metal-bearing particles carried by geogases in near-surface media, such as soil, has not been studied in detail. In this study, metal-bearing nanoparticles were observed in samples from soils and fault gouges over the Shenjiayao gold deposit. The results indicate that (1) the ore-forming elements in soils can only come from deep-seated ore bodies and they occur in nanoparticles in the study area, (2) there is an obvious relationship between metal nanoparticles in fault gouges and soils, (3) the metallic nanoparticles in fault gouges represent a transitional phase along the whole vertical migration process. In addition, the observation results show that the metal-bearing nanoparticles tend to be adsorbed on the surface of clay minerals, which provide theoretical support for using fine fraction soils as sampling media to carry out geochemical exploration in sediment-covered terrains. Based on the results and discussion, a simple migration model was built in this paper.

Northeast China is one of the major wine-making grape bases in China. It is of great significance to study the influence of climate change on grape planting regionalization in northeast China for industrial layout and grape variety selection. According to the 168 weather stations in northeast China Daily meteorological data, calculate the frost-free period, growing season dry degree, active accumulated temperature of April to September, average annual extreme low temperature and other indicators, the 45 years from 1967 to 2011 in the northeast of grapes zoning index change trend, using GIS analysis of wine grapes in the northeast suitable cultivated area change of time and space. The results showed that the temperature increased obviously in the growing season, the indexes such as frost-free period and accumulated temperature of activity increased greatly, the suitable cultivation area of wine grapes expanded greatly to the north, and the dryness changed obviously between generations, showing a rising trend of fluctuation. The impact of climate change on viticulture varies from region to region, but overall, climate change is beneficial to wine viticulture in northeast China. The article also makes a series of Suggestions on how to use the effects of climate change to select varieties and improve wine quality.

The Bayan Obo deposit is the largest deposit of rare earth elements (REEs) in the world, with its light REE (LREE) reserve constituting approximately 45% of the world's total LREEs. This study identifies the geochemical background of REEs in the Bayan Obo region and investigates REE dispersion pattern along a stream, the fractionation between parent rocks and soils, as well as REE distribution in a weathering profile, to reveal the geochemical behavior of REEs during hypergene processes in semi-arid grasslands. Results show that the REE content in the slates of the Bilute, Jianshan, and Dulahala Formations, which are surrounding rocks of the Bayan Obo deposit, is far higher than those observed in ordinary slate and the continental crust of the North China Craton. These surrounding rocks may have provided sufficient REE sources to form the current, huge REE deposit. The total REE content of stream sediments in the Bayan Obo region ranges from 46.9 to 799.8 μg/g, with a median of 170.8 μg/g. Two large-scale REE anomalies were discovered to the west of the Bayan Obo region. The REE content in soil is primarily determined by the parent rock, and no fractionation occurs between heavy REEs (HREEs) and LREEs after the parent rock weathers in semi-arid grasslands. Across the soil profile in Bayan Obo region, REEs typically enrich the surface and deep layers; the middle layer typically contains low REE content owing to the existence of caliche. Along streams, REEs primarily migrate with fine-grained particles over long distances (7 km or longer) via mechanical means. In contrast, coarse-grained particles mainly remain in situ. Affected by aeolian sand, the REE content is relatively low in the 40–80 mesh fraction.

Auriferous pyrite can host a large proportion of gold resource at giant gold deposits all around the world so that these sulfides minerals become key factors to reveal the genesis of ore deposits. In this paper, the focused ion beam-scanning electron microscope (FIB-SEM) method were conducted to present the in-situ transmission electron microscopy (TEM) high resolution images for dislocation ultrastructure study in auriferous pyrite. The TEM diffraction images evidences were provided to prove the evidence that gold cluster at the nanoscale could be existed among crystal interface or even crystal lattice (0.22 nm ~ 0.54 nm). Finally, we have proposed a model that link these nanostructures with gold concentration, gold aggregate in pyrite. The model illustrates the formation pathway of the of discrete invisible gold in pyrite grains which were controlled by shape and ultrastructure of pyrite crystalline, with ion-by-ion rapid diffusion on the surface or lattice. It’s well interpreting for inhomogeneous distribution of nanogold in pyrite resulted from combining with many of these basic pyrite units. In addition, it also reveals unique in-situ measurement result about crystal-fluid interface dynamic that identify the various lattice spacing with possibility for nanoparticle incorporation into deformed pyrite. This study not only provides a new insight into the interpretation of gold distribution and aggregation in pyrite that has significant indication for gold deposit formation in the world, but also provides important evidences for geochemical exploration for concealed deposits based on nanoscale gold.

The Hengduan Mountain region of China is one of the world's highest altitude and lowest latitude wine grape cultivation areas. This study screened the existing regional indexes; the active accumulated temperature (AAT) for grapes in the growing season was chosen as the heat index, and the dryness index (DI) in the growing season was chosen as the water index for climatic regionalization. An analysis of 90-meter resolution digital elevation model (DEM) data and the corresponding slope degree and direction for the Hengduan Mountain region in the range of 97°E-103°E, 27°N-33°N, as well as daily meteorological data over 30 years (1981-2010) from 53 stations in the study region, were used to establish the AAT and DI models for the northern area of the Hengduan Mountains. According to the multiple stepwise regression method, the interaction terms among different geographical and topographic factors were considered. In addition, the residual errors were interpolated and corrected based on the modeling, and this approach further improved the simulation accuracy of meteorological factors. A regional climatic map of wine grapes was produced according to these results. The model was used to calculate the suitable altitude range for wine grape cultivation in different regions of the Hengduan Mountains. The study shows that the distribution of suitable wine grape cultivation areas in the northern part of the mountain range generally mimics distribution of dry warm and dry hot valleys. The accuracy of the results was confirmed based on the existing locations of vineyards in the Hengduan Mountain region.

Geochemical subsoil data obtained from China and European laboratories have been compared in this study. 787 C horizon subsoil samples from FOREGS (Forum of European Geological Surveys) geochemical baselines mapping project were sent to China’s IGGE (Institute of Geophysical and Geochemical Exploration) laboratory and composited to 190 samples according to the 160 km × 160 km GNT (Global Terrestrial Network) cells. In addition to the FOREGS elemental analysis package, Au, Pt, Pd, B, Ge, Br, Cl, Se, N, Li and F were also analyzed by using the IGGE’s 76 element analytical scheme. Geochemical data statistics, scatter plotting, and geochemical map compilation techniques have been employed to investigate differences between FOREGS and IGGE analytical results. The results of two datasets, the IGGE’s analysis data for composited samples, and the FOREGS average data of samples in each GNT cell, agree extremely well for about 23 elements, viz: SiO 2 , Sr, Al 2 O 3 , Zr, Ba, Fe 2 O 3 , Ti, Rb, Mn, Gd, CaO, Ga, MgO, P, Pb, Na 2 O, Y, Th, As, U Sc, Cr, and Co. There are slight differences between-laboratory biases shown as proportional errors between the datasets for Ni, K 2 O, Tb, Tl, Cu, S, Sm, La, Ce, Pr, Nd, Eu, Ho, Er, Tm, Yb, Lu, Ta, Nb, Hf, and Dy. For Cd, Cs, Be, Sb, In, Mo, I, Sn, and Te, the correlation of the two datasets and the similarity of the geochemical maps are fairly good, but obvious biases exist between the two datasets at values near detection limits. Sensitivities of FOREGS analytical methods for W, Bi, Sn, Te, Be, and I are insufficient to produce reportable values in at least 80% of the samples. Although the detection limits of Ag for both FOREGS and IGGE are sufficient to provide reportable values, a large bias was found between the two datasets. This study demonstrates that consistent analytical data for certain elements of global geochemical mapping samples can be achieved by different qualified laboratories, such as China’s IGGE laboratory and some European laboratories. For some elements, such as Ag, further research on the selection of the proper analytical methods and on the development of quality control methods should be undertaken — with final recommendations adhered to by all participants of the global geochemical mapping program.

A series of poly(alkylene succinate) polymers was synthesized from dimethyl succinate and aliphatic diols by the ester-exchange reaction and polyester—alkali metal salt complexes were made by addition of lithium perchlorate to the molten polyester. The thermal stability of the polyesters and complexes were investigated using a conventional dynamic thermogravimetric technique under inert atmosphere and the kinetics of thermal decomposition was studied. The pyrolytic fragments of a polymer and its electrolyte were analysed by combined gas chromatography—mass spectrometry. Decomposition mechanisms are suggested.